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Will TORY LIGHT become an OBM in future?

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Will TORY LIGHT become an OBM in future? 1

Is there a water purifier and a front filter in Longkou city? The potential devices of water purifiers are sold in the city. this is very common, and various brands have

What parts do mechanical filters need? Introduction to adaptive and efficient mechanical filtersThe adaptive high-efficiency mechanical filter adopts the adaptive fiber filter as the core application technology. the filter material used uses the theoretical physics principle-nonlinear scientific fractal structure, and the advantages are self-adaptability and fractal structure. It not only has the efficient filtration accuracy of the fiber filter material, but also has the advantages of using the particle filter material backwashing cleanliness and low water consumption, the pore distribution of filter bed formed by using this filter material is basically close to the ideal filter layer structure. when filtering, the filter material will gradually decrease from large to small along the direction of water flow, and the void ratio distribution in the same section is more uniform, the water flow is consistent in size when filtering.When filtering, due to the poor proportion of the core and the fi

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Surround Sound Made Visible: the New Terrace Theater
Music wants to be democratic; and the Kennedy Center wants to be all things to all people, while signaling a nod to grandeur. Its new Terrace Theater, unveiled this week after a 16-month renovation, manages to carry out this confusing mandate. Where once there was a dizzying descent along sharply raked stairs toward a narrow proscenium, there is now a feeling of spaciousness, with gleaming walls, undulating wood (mimicking the sound waves they reflect), wider aisles and curving balconies swelling from the side walls. "We're 98 percent done," said Deborah Rutter, the Kennedy Center's president, standing in the lobby before the first Fortas Chamber concert in its new home, on Thursday night. How is the new space, with its flexibility a proscenium that can be set up and removed with ease, acoustical curtains behind the paneling that can be drawn to absorb more sound for amplified performances going to affect programming? "It hasn't yet," said Rutter; this season's events were planned while the hall was under construction. "But it will."The prime mandate was "acoustics," says Leora Mirvish, the architect who supervised the Eisenhower Theater renovation in 2008 and now the new Terrace. Whatever its wider uses the opening weekend featured rap and comedy performances its main function remains acoustic music. Jenny Bilfield, president and chief executive of Washington Performing Arts, a frequent renter of the hall, finds that the new Terrace "feels more intimate, elegant, flexible, and has better sightlines and amenities for visitors." That steep descent or ascent to one's seat, though, is still a factor. "We're trying not to be the first casualty in the new Terrace Theater," quipped one woman helping an unsteady man navigate the stairs.Concert halls are reopening all over the place. This weekend, the Freer and Sackler Galleries of the Smithsonian are reopening after an extensive renovation. Its new theater has undergone less a reconfiguration than a facelift, with new carpeting and upholstery, A/V technology, and theatrical lighting. Like the Terrace, the theater is multipurpose; Michael Wilpers, the museums' performing arts programmer, says there are no more than 20 live performances there a year.The Terrace, by contrast, is one of the main small theaters in the city and the Fortas series broke it in lovingly and at considerable length. Patrons got a jolt at the start with two trumpet fanfares (executed with aplomb and agility by Brandon Eubank and Amy McCabe) that demonstrated the hall can be almost too live. The program, called "2-4-6-8," was designed to show the hall in different configurations of instruments, from four-handed piano Joseph Kalichstein and Lisa Emenheiser in enthusiastic Slavonic Dances by Dvorak to the Mendelssohn Octet, with the Emerson and Dover Quartets representing the old and new guards of American chamber music. But the groupings weren't really varied enough no winds, no voices to put the hall fully through its paces, though they added up to almost three hours of energetic music.In general, the space seems more warm and vivid, with a clarity and good sightlines from every corner of the room. It was easy to zero in on the details, from the ping of a broken E string from the Dover's violinist Joel Link in the Brahms G Minor Piano Quartet and the various bobbles of the Emerson's waning violinist Eugene Drucker, sounding a little sour in some romantic passages from Schoenberg's "Verklrte Nacht." None of this mitigated the goodwill in the room, or the impression that the new Terrace Theater remains the Kennedy Center's most pleasant. Washington Performing Arts and the Fortas concerts will jointly present the Sphinx Virtuosi at the Terrace Theater on Sunday afternoon. The Freer and Sackler Galleries are celebrating their reopening with a festival of Asian food and cultures on Saturday and Sunday, including pop-up performances by members of the Silk Road ensemble; there will be one in the new auditorium on Sunday morning.
2021 05 25
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New Apartments in D4, and the Price Is Right From 350,000
The final phase in the popular Fitzwilliam Point apartment development is being launched this week in the south city area at Fitzwilliam Quay in Dublin 4, with substantial price reductions of up to 170,000 per apartment. The units are on view by appointment.Prices are from 350,000 for the two-bedroom apartments (67-78 sqm) reduced from 490,000. There is a one-bed apartment priced at 290,000. The original phase of 85 apartments sold very quickly two years ago.Developer is The Blaney Partnership and the contractor is PJ Walls.Designed by leading architects O'Mahony Pike, the development makes maximum use of natural light. The buildings range from four to five storeys in height and are predominantly comprised of two-bed units in a contemporary style with a very good standard of specification.Fitzwilliam Point is positioned between Fitzwilliam Quay and Fitzwilliam Street in the popular Ringsend Village. There are numerous bus routes stopping close by and the DART stations of Barrow Street and Lansdowne Road are just a short walk away.In recent years there has been a comprehensive regeneration of the south docklands and this has brought new life and activity to the area by day and night.Grand Canal Dock has an abundance of amenities, the highlight being Grand Canal Square, a public plaza designed by Martha Schwartz, which has fountains and public theatrical lighting providing open space for outdoor performances and festivals.The key features of the development are the convenient Dublin 4 location, the central courtyard, the sun balconies, the spacious apartment layouts and very good internal specification and fit-out. The external elevation is impressive.Hooke & MacDonald 01 6318402 are in charge of sales
2021 05 25
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Three Musketeers at Synetic Goes Full Throttle on the Senses
Nearly everything Synetic Theater does could be called Fast and Furious, and the movement-based troupes relentless new The Three Musketeers opens with a tiger pounce as four actors leap out of the darkness toward the audience. Explosive music accompanies the frenzied sword fight; it looks and sounds like a movie trailer for a summer blockbuster.Who are these characters? Doesnt matter. Whirl. Clang. Spin. Punch. Zow! This is how Synetic rolls: The playwright, Ben Cunis (who adapted the famed Alexandre Dumas novel with his brother Peter), not only plays the dashing musketeer Athos, he also does the fight choreography. Thats not vanity. It simply describes the skill set, and the company mind-set. How, they ask, can the story move? Unlike the silent Shakespeare productions (all motion, no speaking) that have won Synetic so much acclaim, Musketeers features plenty of talking, and the Cunis brothers dialogue sometimes manages a kind of cornball charm. Ben Cunis delivers a wry, Kevin Kline-ish performance as the suave but drunken Athos, and Hector Reynosos blustery turn as the plus-sized musketeer Porthos is part of why this light-spirited Musketeers occasionally puts you in mind of The Princess Bride. Director Paata Tsikurishvilis plus-sized production has 16 actors creating crisscrossing mayhem on Synetics Crystal City stage. (Dont even think of going if youre not in the mood for more than two hours of almost manic adventure.) The first swashbuckling act comes off like half-popped popcorn, but you have to giggle at the unapologetic hamminess served up after intermission. If Cunis infectiously enjoys himself as a comic hero, Dan Istrate performs with no less relish as the dastardly, power-grabbing Cardinal Richelieu. The red leather robes and kinky black corset by designer Anastasia R. Simes (who also did the multilevel set thats so ripe for chase scenes) gives Istrate something wicked to live up to, and the actor responds with a creepy turn that pushes the show toward a pulpy edge. But wait theres another villain, and this one dances! Irina Tsikurishvili, as the spidery Milady, tangos with Istrate (Miladys in cahoots with the Cardinal), spins with Cunis (Milady and Athos used to be married long story) and drop-kicks rivals with the aggression of a ticked-off Angelina Jolie. Silly? Yes, but then we havent even come to Robert Bowen Smiths gaudy, low comic vamp as the mincing menace King Louis XIII, resplendent in an all-white, open-collar getup that slightly recalls a latter-day Elvis. None of this is simple, and it rarely looks easy. The actors are in a full sweat mere moments into the show, and while the athleticism is part of what typically impresses with Synetic, so is the discipline. The punches and swordplay are quick, and the tumbling is fearless. Dallas Tolentino is winningly cheerful as the young musketeer-in-training DArtagnan, but the hallmark of his performance and of the show is soaring jumps and nailed landings. The production revs with sensory appeal, from Brittany Dilibertos rock concert lighting design to the sinister/bombastic music by Konstantine Lortkipanidze. This is Synetic at full throttle, although fueled far more by energy than wit. This Musketeers isnt stupid, but its exhausting; while some audiences will be thrilled by the restless propulsion, its fair to wonder if this one-of-a-kind troupe is in danger of getting stuck with its foot on the gas pedal. by Alexandre Dumas. Adapted by Ben and Peter Cunis. Directed by Paata Tsikurishvili. Choreography, Irina Tsikurishvili; sound design, Thomas Sowers. With Matthew Ward, Brittany OGrady, Brynn Tucker, Peter Pereyra, Mitchell Grant, Vato Tsikurishvili, Zana Gankhuyag, Rebecca Hausman, Kathy Gordon and Kathryn Elizabeth Kelly. About 2 1 / 2 hours. Through June 9 at 1800 S. Bell St., Crystal City. Call 800-494-8497 or visit synetictheater.org.
2021 05 25
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Custom Theatrical Lighting Filter on the Cheap
I was recently asked about creating or finding a custom lighting effect for my churchs Christmas Eve program. An outline of a crosswas to be projected on stage; I searched a bit on the web but was unable tofind instructions on making DIY filters. I had some ideas of my own and wantedto test them out.The filter is a low budget GOBO filter made from kitchen grade aluminum foil and securedwith kapton tape which is temperature rated for 500F/260C. This can be foundon-line or at some electronics stores.I did not start completely from scratch; I had a theatrical light fixture as we have about a dozen theatrical lights suspended for the stage. I was able to repurpose one for this effect.Removing the lens assembly, I was fortunate to find innerframe areas to mount onto. I measured the opening and determined a size for thefoil filter, 4 was chosen.The aluminum foil shape was cut with an X-Acto knife after placingit on a smooth scrap board. Other cutting techniques such as scarp-bookingstamps should work as well.Securing the filter within the fixture was quite simple. Asstated earlier there was a internal ring frame that I was able to affixto. Using only four pieces of tape inlength provided adequate security for the lightweight filter. Remember, thefilter MUST be mounted upside down as the image is inverted by the lenses. Alsothe fixture used had slide dampers to shape the light, these were used toreduce the amount of light getting to filter and provide more of a heat block.I slide in dampers till they just reached the outline of the filter with thefixture illuminated.The result was used to shine on an empty throne (chair) andthough it was only panned in for a minute at a key moment during a particularsong it had the desired effect. No color filter was added though that would of course be simple.The lighting bar in the church was mounted too close tostage to focus the light fixture by normal means of the lens screw in theprovided slot. I had to extend the lensassembly further and secure with duct tape and a safety string to the setscrew.
2021 05 25
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Lego Builders of All Ages Unite at Convention in Richmond
Builders who have passed through their "Dark Ages" without Lego rediscover their youthWhen you imagine a Lego convention, your mind might conjure up a hall packed with kids indulging in their innate instinct to play.That would be about one-third correct. The other two-thirds are adults every bit as tapped into theirs.Thousands of Lego fans gathered over the weekend at the fourth BrickCan, a large exhibition of Lego held at Richmonds River Rock Casino Resort. What drew them were scores of astonishing creations assembled by Lego builders from around the world who are mature in both skill and age, many having spent decades practicing the art of building.Christina Loch created Museum of Textiles in the Fashion Arts for BrickCan 2019 at the River Rock Casino in Richmond. Photo: Arlen Redekop, PostmediaArlen Redekop / PNGBy some measures, builder Christina Loch is a relative newcomer to the world of Lego. Her rekindled enthusiasm for the building blocks kicked in just a few years ago, after she won a fight with cancer.I use this as art therapy, Loch said Sunday.The intricate, multidisciplinary work that Loch brought to display at the show was a modern and minimalist-looking original concept museum she dubbed the Museum of Textiles in the Fashion Arts, or MoTIF Arts, for short. The work blended her interests in architecture, interior design and textiles, she said.Inside MoTIF Arts is a miniature replica of a commercial flatbed fabric printer that is running a strip of hand-painted rice paper. On display in other sections of the museum are hand-painted fabric clothing and banners. The museums Textile Studio and Programs Department features replicas of an Ancient Greek warp-weighted loom, a silk spinner and a drop spinner.A program schedule posted outside the museum tells visitors what to expect inside. On Monday is a demonstration on spinning yarn using the drop spindle. On Wednesdays is a class on spinning silk thread from silk worms.Other creations built by Lochs fellow Adult Fans of Lego and on display at BrickCan included intricate castles, sleek fighter jets, cityscapes and spaceships, and even a full amusement park complete with moving carousels and thrill rides, a ferris wheel and a roller coaster.Jason von Innerebner displays his Flix Theatre at BrickCan 2019 at the River Rock Casino in Richmond. Photo: Arlen Redekop, PostmediaArlen Redekop / PNGJason von Innerebner built an impressive piece he dubbed Flix Theatre, a cinema with a balcony, grand staircases, theatre lighting, and a built-in pre-film animation wheel that presents a moving picture. Star Wars a Brix Flix reads a scrolling marquee out front. The moving image is of a lightsabre battle between Darth Vader and a disposable Jedi, as von Innerebner put it.The theatre was built with 30-40 thousand pieces, he said.Ley Ward is among the organizers of the convention. He became an avid builder around the age of 10 and made many creations before he entered a period that builders chillingly refer to as their Dark Age a phase when Lego is tucked into a closet, passed on to children, or sold at garage sales rather than being used.Wards Dark Age lasted 25 years. He is now 58, the owner of an estimated half-million bricks, and nicknamed the Wizard for his building skills.Its just really fun to challenge yourself and see what you can come up with, and to bounce ideas off each other, which is what we do here. Were brainstorming stuff for next year already, he said.Nicole Gent and Colby Goss created The Sea of Wonders for BrickCan 2019 at the River Rock Casino in Richmond. Photo: Arlen Redekop, PostmediaArlen Redekop / PNGJames Cornthwaite used approx 6000 pieces to build this Space Shuttle Orbiter for BrickCan 2019 at the River Rock Casino in Richmond. Photo: Arlen Redekop, PostmediaArlen Redekop / PNG
2021 05 25
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London 2012 Basketball Arena / Wilkinson Eyre Architects
Edmund Sumner Architects: Wilkinson Eyre Architects Location: Olympic Park North (Stop M), London Borough of Hackney, London E9, UK Project Team: SKM with Wilkinson Eyre Architects and KSS Project Year: 2011 Project Area: 11500.0 sqm Photographs: Edmund Sumner The Basketball Arena by Wilkinson Eyre Architects is one of the biggest temporary venues ever erected for any Olympic and Paralympic Games and the third largest venue in the Olympic Park. Located on high ground at the north end of the site, and clearly visible from various vantage points in the Olympic Park, the Arena will provide 12,000 seats for the basketball heats and handball finals, as well as 10,000 seats for the wheelchair basketball and wheelchair rugby competitions. Despite a tight budget, the Arena is set to be one of the most iconic and visually dramatic buildings of the 2012 Games. Edmund Sumner The brief called for a structure that was simple to erect but also provided a worldclass sporting venue for some of the most popular Olympic events. Alongside these factors, sustainability was a key driver in the buildings design: the arena has been made out of robust individual components that can be easily dismantled and subdivided for reuse, with over twothirds of the materials and components used on the project identified for reuse or for recycle. Section 03 Wilkinson Eyre has used an architectural language that remains distinct from the surrounding permanent venues, overtly celebrating both the best of British engineering and the temporary nature of the structure through innovative and economic structural and cladding solutions. Lightweight, simple building components have been used instead of a concrete structure usually found in stadia architecture, allowing the Basketball Arenas steel frame and cladding to be constructed in just six weeks. Edmund Sumner The 30mhigh rectangular volume (the equivalent of a sevenstorey building) is made out of a steel portal frame and wrapped in 20,000 sqm of lightweight phthalatefree and recyclable PVC. This translucent bespoke cladding is stretched across minimal steel framing modules that push the fabric out and create an elegant and threedimensional undulating pattern across the facades. The roof fabric includes an interwoven blackout layer that eliminates daylight during game sessions and maintains fully controllable artificial lighting for the media. The external walls are translucent, allowing daylight to filter through during the day and artificial lighting to be visible in the evening. Edmund Sumner The variation of surface qualities used throughout the structure help animate the buildings exterior, with the expression of the building being derived from the play of sunlight and nighttime theatrical lighting across the fabric surface. Wilkinson Eyre worked with United Visual Artists, specialists in concert lighting and installations, to create lighting and colourchanging effects for the evening games. The result is a dynamic illumination which, at night, transforms the white surface into a variety of saturated colours and strong silhouettes of the substructure, creating the biggest light installation on the Olympic park. Edmund Sumner Modular accommodation units that serve as the back of house areas are located outside the Arena volume, which also shares LOCOG overlay facilities with the Velodrome and BMX Track. These will include warmup courts and areas for catering, security, waste management and the media. Diagrams 01 Wilkinson Eyre worked Sinclair Knight Mertz (project management, structural and MEP consulting) and sports consultants KSS on the project. London 2012 Basketball Arena / Wilkinson Eyre Architects originally appeared on ArchDaily, the most visited architecture website on 22 Jul 2012. send to Twitter | Share on Facebook | What do you think about this?
2021 05 25
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How to Interpret Visual Fields
IntroductionImagine you are assessing a patient with visual difficulties or optic disc swelling. After a bedside visual field examination with waggling fingers and even a red hatpin, you decide that there is an abnormality. After requesting quantified visual field tests, the patient returns with a black and white printout with numbers (eg, Humphrey fields) or coloured lines on a sheet (eg, Goldmann fields). Where is the report you ask? There is none!Static perimetry uses flashing stationary lights. This can be automated (eg, evenly spaced points on a grid) or manual (eg, as a small part of Goldmann test: detailed later). The Humphrey field analyser is by far the most commonly used for automated static perimetry, although there are also other machines such as Octopus and Henson. Later, we describe in detail the interpretation of Humphrey perimetry. oas_tag.loadAd("Middle1"); Kinetic perimetry uses a moving illuminated target and is done either manually (eg, Goldmann) or on an automated machine (eg, Octopus). Goldmann machines are no longer manufactured, being slowly replaced by Octopus machines. Nevertheless, Goldmann remains the most commonly used kinetic perimetry, and so we use this here to illustrate interpretation of kinetic fields. The principles for interpreting Goldmann also apply to results from Octopus machines.It is beyond the scope of this paper to cover the neuroanatomical localisation of visual field defects. Instead we recommend two excellent recent reviews.1 ,2 Skilled interpretation of visual field tests requires a good grasp and application of this prior knowledge.Useful aspects of eye anatomyThe fovea is the area of greatest visual sensitivity, where the cone photoreceptor density is at its highest. The visual sensitivity slopes off further from the fovea. This drop in sensitivity can be visualised as a hill, with the fovea is at the peak (figure 1). Conventional perimetry is carried out under photopic (well lit) conditions, and therefore, rod photoreceptors do not contribute to the findings.The normal field of vision extends to approximately 60 nasally, 90 temporally, 60 superiorly and 70 inferiorly.The blind spot indicates the location of the optic nerve headan area with no photoreceptorsin the temporal part of the visual field.Anything obstructing the travel of light towards the retina may affect the field tests, for example, lens opacity (cataract), ptosis (if not taped away from the pupil) or the rim of a correcting lens (test artefact)Download figure Open in new tab Download powerpoint Figure1 Normal hill of vision.Goldmann field testDuring a Goldmann field test, the patient positions their eye opposite the centre of a white hemispherical bowl (figure 2). The patient fixates upon the central target 33 cm away, while the examiner sits opposite viewing through an eyepiece to ensure good fixation throughout the test. The examiner moves an illuminated white target from the periphery towards the centre, and the patient presses a buzzer to indicate when they first see the target. This is repeated from different directionsallowing the examiner to plot the patient's field of visionusing targets varying in size and brightness. The examiner plots the blind spot and the edges of scotomas in a similar way, with the patient pressing the buzzer to indicate when they first see the light target moving from a blind to a seeing area. The examiner also performs static testinginvolving the brief appearance of the stationary light targetin the four quadrants within the central 20 or so, marking a tick on the chart when the patient sees the target and a cross if they do not.Download figure Open in new tab Download powerpoint Figure2 Goldmann machine. The patient's eye is positioned at the centre of a white hemispheric bowl, with the examiner looking through an eyepiece to ensure good fixation. A white light (indicated by yellow arrow in (A) is brought in from the periphery into the patient's field of vision. The examiner does this by controlling connecting levers (indicated by orange arrows in A and B). The patient presses a buzzer when the light target is seen (blue arrow).The target sizes are labelled with three alphanumeric digits, for example, V4e. The first digit is a Roman numeral (IV), indicating the size of the target, for example, V is equivalent to a target diameter of 9.03 mm. With every drop in number (eg, from V to IV) the diameter halves.The second digit is an Arabic number (14), indicating the brightness of the stimulus: the larger the number the higher the luminance.The third digit is a letter (ae), indicating a finer calibration of luminance. 4e is equivalent to 10-decibel (dB) brightness; each consecutive drop in number represents a 5 dB change and each drop in letter represents a 1 dB change.By convention, the examiner maps three isopters: lines of equal sensitivity to targets of a specified size and luminance. The first isopter, mapping the farthest peripheral vision, requires the largest and brightest target V4e. Another isopter is mapped in the central 30 of vision, and a third isopter is intermediate between these two. The isopter lines therefore show the margins of different visual sensitivity, analogous to the contour lines of a map marking different elevations. This allows us to visualise the hill of vision. The base of the hill represents the area at the periphery with least visual sensitivity, detecting only the largest and brightest target. As we move up towards the peak of the hill, the visual sensitivity increases and the patient sees smaller and dimmer targets.Humphrey field testThe same principles apply to the Humphrey test as to the Goldmann test, but instead with static light stimulation. The machine can also be programmed to perform kinetic tests though we have no experience with this.The illuminated targets appear for 200 ms at predetermined locations on a grid. Humphrey tests are widely used in glaucoma clinics, the most common set up being to test the central 24 (24-2 setting). Some examiners test smaller or wider visual angles; however, the wider the visual angle tested, the more coarse the grid, and hence the greater the likelihood of missing small scotomas. The 24-2 assesses the central 24 with a 54-point grid; 10-2 assesses the central 10 with a 68-point grid; and 30-2 assesses the central 30 with a 76-point grid.The examiner plots the hill of vision based upon the threshold for detecting different target luminance; as visual sensitivity improves towards the fovea, so the detection threshold for the target decreases. Unlike Goldmann, the target size stays the same during the test, with a default size equivalent to Goldmann size III targets. It is rare to need a different default size.The Swedish interactive threshold algorithm (SITA) is the most commonly used test algorithm,3 designed to reduce the time to complete a test; a short test duration limits the likelihood of errors from patient fatigue. SITA starts by determining the visual stimulation thresholds at the four quadrants. If the patient sees the initial stimulus, the examiner reduces its brightness to the level where it is no longer seen. Conversely, if the patient does not see the stimulus, its brightness is increased to find this threshold. The examiner adjusts the initial brightness at adjacent points according to the threshold of its neighbouring point. During the test, the examiner retests some locations to determine reliability (see false-negative errors, below). At completion, the computer generates a statistical analysis, which is compared to an age-matched normal population. Useful aspects of eye anatomyThe fovea is the area of greatest visual sensitivity, where the cone photoreceptor density is at its highest. The visual sensitivity slopes off further from the fovea. This drop in sensitivity can be visualised as a hill, with the fovea is at the peak (figure 1). Conventional perimetry is carried out under photopic (well lit) conditions, and therefore, rod photoreceptors do not contribute to the findings.The normal field of vision extends to approximately 60 nasally, 90 temporally, 60 superiorly and 70 inferiorly.The blind spot indicates the location of the optic nerve headan area with no photoreceptorsin the temporal part of the visual field.Anything obstructing the travel of light towards the retina may affect the field tests, for example, lens opacity (cataract), ptosis (if not taped away from the pupil) or the rim of a correcting lens (test artefact)Download figure Open in new tab Download powerpoint Figure1 Normal hill of vision. Goldmann field testDuring a Goldmann field test, the patient positions their eye opposite the centre of a white hemispherical bowl (figure 2). The patient fixates upon the central target 33 cm away, while the examiner sits opposite viewing through an eyepiece to ensure good fixation throughout the test. The examiner moves an illuminated white target from the periphery towards the centre, and the patient presses a buzzer to indicate when they first see the target. This is repeated from different directionsallowing the examiner to plot the patient's field of visionusing targets varying in size and brightness. The examiner plots the blind spot and the edges of scotomas in a similar way, with the patient pressing the buzzer to indicate when they first see the light target moving from a blind to a seeing area. The examiner also performs static testinginvolving the brief appearance of the stationary light targetin the four quadrants within the central 20 or so, marking a tick on the chart when the patient sees the target and a cross if they do not.Download figure Open in new tab Download powerpoint Figure2 Goldmann machine. The patient's eye is positioned at the centre of a white hemispheric bowl, with the examiner looking through an eyepiece to ensure good fixation. A white light (indicated by yellow arrow in (A) is brought in from the periphery into the patient's field of vision. The examiner does this by controlling connecting levers (indicated by orange arrows in A and B). The patient presses a buzzer when the light target is seen (blue arrow).The target sizes are labelled with three alphanumeric digits, for example, V4e. The first digit is a Roman numeral (IV), indicating the size of the target, for example, V is equivalent to a target diameter of 9.03 mm. With every drop in number (eg, from V to IV) the diameter halves.The second digit is an Arabic number (14), indicating the brightness of the stimulus: the larger the number the higher the luminance.The third digit is a letter (ae), indicating a finer calibration of luminance. 4e is equivalent to 10-decibel (dB) brightness; each consecutive drop in number represents a 5 dB change and each drop in letter represents a 1 dB change.By convention, the examiner maps three isopters: lines of equal sensitivity to targets of a specified size and luminance. The first isopter, mapping the farthest peripheral vision, requires the largest and brightest target V4e. Another isopter is mapped in the central 30 of vision, and a third isopter is intermediate between these two. The isopter lines therefore show the margins of different visual sensitivity, analogous to the contour lines of a map marking different elevations. This allows us to visualise the hill of vision. The base of the hill represents the area at the periphery with least visual sensitivity, detecting only the largest and brightest target. As we move up towards the peak of the hill, the visual sensitivity increases and the patient sees smaller and dimmer targets. Humphrey field testThe same principles apply to the Humphrey test as to the Goldmann test, but instead with static light stimulation. The machine can also be programmed to perform kinetic tests though we have no experience with this.The illuminated targets appear for 200 ms at predetermined locations on a grid. Humphrey tests are widely used in glaucoma clinics, the most common set up being to test the central 24 (24-2 setting). Some examiners test smaller or wider visual angles; however, the wider the visual angle tested, the more coarse the grid, and hence the greater the likelihood of missing small scotomas. The 24-2 assesses the central 24 with a 54-point grid; 10-2 assesses the central 10 with a 68-point grid; and 30-2 assesses the central 30 with a 76-point grid.The examiner plots the hill of vision based upon the threshold for detecting different target luminance; as visual sensitivity improves towards the fovea, so the detection threshold for the target decreases. Unlike Goldmann, the target size stays the same during the test, with a default size equivalent to Goldmann size III targets. It is rare to need a different default size.The Swedish interactive threshold algorithm (SITA) is the most commonly used test algorithm,3 designed to reduce the time to complete a test; a short test duration limits the likelihood of errors from patient fatigue. SITA starts by determining the visual stimulation thresholds at the four quadrants. If the patient sees the initial stimulus, the examiner reduces its brightness to the level where it is no longer seen. Conversely, if the patient does not see the stimulus, its brightness is increased to find this threshold. The examiner adjusts the initial brightness at adjacent points according to the threshold of its neighbouring point. During the test, the examiner retests some locations to determine reliability (see false-negative errors, below). At completion, the computer generates a statistical analysis, which is compared to an age-matched normal population. Humphrey or Goldmann?The choice may depend upon local availability. The Humphrey is slightly less operator-dependent than the Goldmann and has the advantage of numbers to indicate reliability of the test. The Goldmann tests peripheral fields better, may be more patient-friendly for those who are hesitant on the Humphrey, and is particularly useful for central scotoma, as it is easier to manage fixation losses. As a rule of thumb, when monitoring disease, it is sensible to use the same test as was used previously. Both tests can complement each other, confirming deficit patterns when in doubt.Interpreting the Goldmann field testThe key to interpreting Goldmann visual fields is to keep in mind the normal hill of vision (figure 1) and how it compares with the patient's results. The skill is in identifying patterns and observing any change with repeated tests. This may require experience to be adept, though the following checklist may help (figure 3): Patient name and date of test: a good habit always to check the test belongs to your patient!What is the largest peripheral field (V4e)? This can vary according to age and test response. It normally extends to approximately 60 nasally, 90 temporally, 60 superiorly and 70 inferiorly. Thus, the superior aspect of the field is usually less sensitive than the inferior field, though ptosis could also artefactually reduce it.Is there any distortion to the contours? (Contours are the smaller isopters corresponding to targets that are either smaller or dimmer or both). Is the isopter smooth, as expected for a normal hill of vision?Is there restriction? Examples would be a nasal step in papilloedema or an altitudinal defect in anterior ischaemic optic neuropathy.Are the isopters spaced, as expected for the normal hill of vision? (1) A tiny central field with stacked isoptersvery close to one another as in a steep hillusually denotes functional overlay (figure 7); however, patients with genuine retinal and striate cortex lesions may also have stacked isopters. (2) Isopter lines that cross always indicate unreliable test: isopters cannot cross since this would indicate two different sensitivities at one location. (3) Spiralling isopters suggest functional visual loss and indicate a steady decline in sensitivity during the test.Are there scotomas? It is important to correlate this with the patient's symptoms and clinical (bedside) examination.Is the blind spot size enlarged? This is particularly relevant in papilloedema (figure 5). The normal blind spot size is oval, roughly 10 in diameter, and located 1020 temporally from the central fixation point.Is the central field affected? Was static testing done (indicated with a tick when the patient saw the target)?Is any defect monocular or binocular, when comparing the fields for each eye? If binocular, is the defect homonymous or heteronymous?Any comments written about patient fixation or attention also help. Small pupil size, ptosis and incorrect positioning of a correcting lens may affect the peripheral field.Inadequate correction of refraction error for the viewing distance (33 cm) may affect the central field.Download figure Open in new tab Download powerpoint Figure3 Interpreting the Goldmann visual field.The chart is viewed from the perspective of the patient looking into the test bowl, as if patient is looking into the paper. Suggested checklist to review the Goldmann fields systematically (see text for details):1. Patient name and identification number, date of test.2. The largest isopter, that is, peripheral field.3. The other isoptersany distortion to the contours of the hill of vision? Any scotomas?4. Blind spot.5. Central vision.6. If there is an abnormality, is it monocular or binocular? If binocular, is it homonymous or heteronymous?7. Other, for example, comments about fixation or attention.This is an example of normal Goldmann fields. In contrast, this patient did not perform well on the Humphrey visual fields, with poor reliability and cloverleaf pattern (figure 4).Download figure Open in new tab Download powerpoint Figure4 Interpreting the Humphrey visual field. The charts are viewed from the perspective of the patient looking into the test bowl, as if patient is looking into the paper. Suggested checklist to systematically review Humphrey visual fields (see text for details): 1. Is this the correct test? A. Patient name and identification number B. Date of test C. Left or right eye? D. Test performed degree of visual angle tested test protocol: threshold or screening2. Can I rely on this test? A. False-positive errors B. False-negative errors C. Fixation-loss index D. Gaze-tracking graph 3. Is the test normal? A. Visual sensitivity map B. Total deviation map C. Pattern deviation mapThis patient's test was unreliable: high fixation loss index (and comment from technician, patient advised several times for both eyes (suggesting poor compliance), gaze-tracking graph also showed eye movements (indicated by upward spike from baseline) and high false-negative errors, up to 20% in the left eye. The grey scale visual sensitivity map suggests a clover leaf type pattern (figure 9). This provided the impression that the patient had difficulty with the Humphrey test itself. Clinical examination including visual acuity, colour vision, pupillary examination and visual field to confrontation to red pin was normal. The patient's Goldmann visual field test was normal (figure 3).Download figure Open in new tab Download powerpoint Figure5 Goldmann visual field from papilloedema. This patient has papilloedema from idiopathic intracranial hypertension. Goldmann fields show (1) an enlarged blind spot and (2) inferonasal field restriction.Download figure Open in new tab Download powerpoint Figure6 Goldmann visual fields of a patient with right optic neuropathy. All isopters are restricted but with preserved contours of the hill of vision, giving the appearance of a sunken hill. Compare this with figure 7 showing stacked isopters in a patient with functional visual loss.Download figure Open in new tab Download powerpoint Figure7 Goldmann visual fields of a patient with stacked isopters. This patient has functional overlay of a previous episode of mild optic neuritis affecting the right eye. Compare this with figure 6 of another patient with optic neuropathy. These stacked isopters would represent a hill vision that is too steep to be physiological, that is, the close contours here appear like a cliff drop. Clinical examination with a red target confirmed the presence of a tubular field (figure 8), with the size of visual field remaining unchanged when examined at 1 and 4 m. This is not keeping with the optics of light, whereby at a constant visual angle, the size of the field would appear larger the further away, that is, when examined at 4 m (with a proportionately larger target for acuity), the size of field to confrontation should be larger than on examination at 1 m.Download figure Open in new tab Download powerpoint Figure8 Tunnel vision: functional (ie, tubular field) versus physiological. The optics of light is such that at a constant visual angle, the size of the field appears larger when further away. When examined at 4 m (with a proportionately larger target for acuity), the size of field to confrontation should be larger than on examination at 1 m. Thus, a tubular field, where the size of field is unchanged, suggests functional overlay.Download figure Open in new tab Download powerpoint Figure9 Cloverleaf pattern on Humphrey visual fields. This artefactual visual field defect results from a reduced response rate as the test progresses. The Swedish interactive threshold algorithm (SITA) threshold test starts by determining the initial brightness in the four quadrants using the four points indicated by the arrows. Therefore, if a patient's response deteriorates as the test progresses, for example, because of reduced concentration, the visual field shows a cloverleaf pattern, where the thresholds are low at the four points initially tested and higher for the surrounding points. This pattern commonly occurs in non-organic visual loss and is equivalent to spiralling on the Goldmann. There will also be a high rate of negative errors. (A) Shows an example where the patient stops responding very early in the test, giving an extreme example of the cloverleaf pattern; (B) shows another example of cloverleaf pattern.Interpreting the Humphrey field testWe suggest the following framework to interpret Humphrey test results (figure 4), structured to answer three questions: 1. Is this the correct test?A. Name and patient number: confirm that the output belongs to your patient!B. Date of test: is this the output of interest? that is, timing in relation to symptoms.C. To which eye does this output correspond? Correlate the results with the history and clinical examination. Beware of fields that are mounted incorrectly: the conventional way of mounting is to place the left chart on the right and vice versa, ie, as if the patient is looking into the chart.D. What test was performed? This is particularly important when comparing to any previous tests.a. What degree of visual angle was tested?Most commonly set to 24-2 (central 24 tested with a 54-point grid). A smaller field with higher concentration of points gives further details of the foveal region. For example, 10-2 assesses the central 10 with a 68-point grid. 30-2 is similar to 24-2 but with an additional 6 and with a corresponding increase in the points tested (76-point grid for 30); thus, this is a longer test with the risk of more patient errors.b. Was it a threshold or a screening test?Screening tests use suprathreshold targets of single luminance and in the past were particularly useful because full threshold tests were time consuming. However, SITA threshold tests have superseded these, reducing test times (equivalent to the time taken for screening tests) without losing sensitivity.2. Can I rely on this test?A. False-positive errorsFalse-positive errors identify trigger happy patients who respond in the absence of light stimulus. They are calibrated according to the patient's overall responses, therefore detecting when responses occur too soon after presenting a stimulus is. A false-positive rate of >15% compromises test results.4B. False-negative errorsA false negative is the failure to respond to a relatively bright suprathreshold target in a region that previously responded to fainter stimuli. A high false-negative index may indicate hesitation or inattentiveness, though a true scotoma may also give false-negative results. However, in a true scotoma, the false-negative error rate is low for the contralateral (normal) eye.4 False-negative error may reduce with repeated testing as the patient gets used to the testing procedure.C. Fixation-loss indexFixation loss is tested by presenting a stimulus at the blind spot. If the patient sees this stimulus, it indicates loss of fixation. Values of >20% can compromise the test.4 However, this number could be artefactually elevated if the blind spot was inaccurately located, or in trigger-happy patients. Tracking of the gaze (below) is better for assessing fixation loss.D. Gaze-tracking graphThe eyes are tracked using video. The gaze tracking graph shows an upward spike when the eyes move and a downward spike when the eyes blink.3. Is the test normal?Three maps are generated with numbers and pictorial representations:A. Visual sensitivity mapThe numbers indicate the threshold of stimulus intensity detected in decibel (dB), with zero corresponding to the brightest intensity. Typical normal values centrally are around 30 dB. Values of 40 dB should not appear in standard test conditions but could occur in patients with high false-positive errors. The visual sensitivity may improve with repeat testing as patients become more familiar with it. The grey scale map is a visual representation of the numbers, with darker areas indicating poorer sensitivity to stimuli.B. Total deviation mapThis shows the deviations of the patient's visual sensitivity compared to an age-matched normal population. The numbers indicate the difference compared to the mean, that is, a negative value indicates less visual sensitivity compared to the mean population. The probability plot gives a visual representation of statistical analysis (t test) of this deviation from the mean; the larger departure from the mean, the darker the symbol.C. Pattern deviation mapThis shows the deviation of the pattern from a normal visual hill, where the peak is at the fovea. The numeric values show any departure from the mean of an age-matched population, and as above, the probability plot is a visual representation of statistical analysis indicating the extent of departure from mean. The pattern deviation adjusts for any shifts in overall sensitivity: for example, a patient with cataract might have a smaller or sunken hill but with normal contour patterns.By statistical chance, patients may have a few scattered dark symbols on the probability map, which may not be of concern. Instead, look for patterns, for example, whether these are around the blind spot, which might indicate a true enlargement. It is important to correlate the test results with the history and clinical examination.The visual sensitivity, total deviation and pattern deviation maps should be viewed together for any discrepancies. It is worth noting the following scenarios: Abnormal grey scale on stimulus intensity map but normal probability plots: lid partially obscuring the superior field.Abnormal total deviation but normal pattern deviation: cataract, small pupils, incorrect correction for refractive error.Abnormal pattern deviation but normal total deviation: a test with high false-positive (trigger happy) patient.Additional information that may help, especially when comparing with previous tests, include pupil diameter (is there a wide variation between tests?), lens modification (was the same correction used?), time taken to do the test (was this particularly long?). The global indices show the mean deviations, which can help to monitor progression, especially in glaucoma.Three summary indices appear on the printout4: The visual field index is a staging index designed to correspond to ganglion cell loss, that is, 100% represents normal fields and 0% represents blind fields.The mean deviation represents the degree of departure of the whole field's average values, from age-adjusted normal values.The pattern SD represents irregularities within the field, for example, of localised field defects. This can be small in completely normal patients or in those with complete blindness.The visual field index and the mean deviation can help to identify progression; the visual field index may be less prone to artefacts from cataract. These values may help to monitor progression, but with caution, since artefacts and test reliability can affect them. Interpreting the Goldmann field testThe key to interpreting Goldmann visual fields is to keep in mind the normal hill of vision (figure 1) and how it compares with the patient's results. The skill is in identifying patterns and observing any change with repeated tests. This may require experience to be adept, though the following checklist may help (figure 3): Patient name and date of test: a good habit always to check the test belongs to your patient!What is the largest peripheral field (V4e)? This can vary according to age and test response. It normally extends to approximately 60 nasally, 90 temporally, 60 superiorly and 70 inferiorly. Thus, the superior aspect of the field is usually less sensitive than the inferior field, though ptosis could also artefactually reduce it.Is there any distortion to the contours? (Contours are the smaller isopters corresponding to targets that are either smaller or dimmer or both). Is the isopter smooth, as expected for a normal hill of vision?Is there restriction? Examples would be a nasal step in papilloedema or an altitudinal defect in anterior ischaemic optic neuropathy.Are the isopters spaced, as expected for the normal hill of vision? (1) A tiny central field with stacked isoptersvery close to one another as in a steep hillusually denotes functional overlay (figure 7); however, patients with genuine retinal and striate cortex lesions may also have stacked isopters. (2) Isopter lines that cross always indicate unreliable test: isopters cannot cross since this would indicate two different sensitivities at one location. (3) Spiralling isopters suggest functional visual loss and indicate a steady decline in sensitivity during the test.Are there scotomas? It is important to correlate this with the patient's symptoms and clinical (bedside) examination.Is the blind spot size enlarged? This is particularly relevant in papilloedema (figure 5). The normal blind spot size is oval, roughly 10 in diameter, and located 1020 temporally from the central fixation point.Is the central field affected? Was static testing done (indicated with a tick when the patient saw the target)?Is any defect monocular or binocular, when comparing the fields for each eye? If binocular, is the defect homonymous or heteronymous?Any comments written about patient fixation or attention also help. Small pupil size, ptosis and incorrect positioning of a correcting lens may affect the peripheral field.Inadequate correction of refraction error for the viewing distance (33 cm) may affect the central field.Download figure Open in new tab Download powerpoint Figure3 Interpreting the Goldmann visual field.The chart is viewed from the perspective of the patient looking into the test bowl, as if patient is looking into the paper. Suggested checklist to review the Goldmann fields systematically (see text for details):1. Patient name and identification number, date of test.2. The largest isopter, that is, peripheral field.3. The other isoptersany distortion to the contours of the hill of vision? Any scotomas?4. Blind spot.5. Central vision.6. If there is an abnormality, is it monocular or binocular? If binocular, is it homonymous or heteronymous?7. Other, for example, comments about fixation or attention.This is an example of normal Goldmann fields. In contrast, this patient did not perform well on the Humphrey visual fields, with poor reliability and cloverleaf pattern (figure 4).Download figure Open in new tab Download powerpoint Figure4 Interpreting the Humphrey visual field. The charts are viewed from the perspective of the patient looking into the test bowl, as if patient is looking into the paper. Suggested checklist to systematically review Humphrey visual fields (see text for details): 1. Is this the correct test? A. Patient name and identification number B. Date of test C. Left or right eye? D. Test performed degree of visual angle tested test protocol: threshold or screening2. Can I rely on this test? A. False-positive errors B. False-negative errors C. Fixation-loss index D. Gaze-tracking graph 3. Is the test normal? A. Visual sensitivity map B. Total deviation map C. Pattern deviation mapThis patient's test was unreliable: high fixation loss index (and comment from technician, patient advised several times for both eyes (suggesting poor compliance), gaze-tracking graph also showed eye movements (indicated by upward spike from baseline) and high false-negative errors, up to 20% in the left eye. The grey scale visual sensitivity map suggests a clover leaf type pattern (figure 9). This provided the impression that the patient had difficulty with the Humphrey test itself. Clinical examination including visual acuity, colour vision, pupillary examination and visual field to confrontation to red pin was normal. The patient's Goldmann visual field test was normal (figure 3).Download figure Open in new tab Download powerpoint Figure5 Goldmann visual field from papilloedema. This patient has papilloedema from idiopathic intracranial hypertension. Goldmann fields show (1) an enlarged blind spot and (2) inferonasal field restriction.Download figure Open in new tab Download powerpoint Figure6 Goldmann visual fields of a patient with right optic neuropathy. All isopters are restricted but with preserved contours of the hill of vision, giving the appearance of a sunken hill. Compare this with figure 7 showing stacked isopters in a patient with functional visual loss.Download figure Open in new tab Download powerpoint Figure7 Goldmann visual fields of a patient with stacked isopters. This patient has functional overlay of a previous episode of mild optic neuritis affecting the right eye. Compare this with figure 6 of another patient with optic neuropathy. These stacked isopters would represent a hill vision that is too steep to be physiological, that is, the close contours here appear like a cliff drop. Clinical examination with a red target confirmed the presence of a tubular field (figure 8), with the size of visual field remaining unchanged when examined at 1 and 4 m. This is not keeping with the optics of light, whereby at a constant visual angle, the size of the field would appear larger the further away, that is, when examined at 4 m (with a proportionately larger target for acuity), the size of field to confrontation should be larger than on examination at 1 m.Download figure Open in new tab Download powerpoint Figure8 Tunnel vision: functional (ie, tubular field) versus physiological. The optics of light is such that at a constant visual angle, the size of the field appears larger when further away. When examined at 4 m (with a proportionately larger target for acuity), the size of field to confrontation should be larger than on examination at 1 m. Thus, a tubular field, where the size of field is unchanged, suggests functional overlay.Download figure Open in new tab Download powerpoint Figure9 Cloverleaf pattern on Humphrey visual fields. This artefactual visual field defect results from a reduced response rate as the test progresses. The Swedish interactive threshold algorithm (SITA) threshold test starts by determining the initial brightness in the four quadrants using the four points indicated by the arrows. Therefore, if a patient's response deteriorates as the test progresses, for example, because of reduced concentration, the visual field shows a cloverleaf pattern, where the thresholds are low at the four points initially tested and higher for the surrounding points. This pattern commonly occurs in non-organic visual loss and is equivalent to spiralling on the Goldmann. There will also be a high rate of negative errors. (A) Shows an example where the patient stops responding very early in the test, giving an extreme example of the cloverleaf pattern; (B) shows another example of cloverleaf pattern. Interpreting the Humphrey field testWe suggest the following framework to interpret Humphrey test results (figure 4), structured to answer three questions: 1. Is this the correct test?A. Name and patient number: confirm that the output belongs to your patient!B. Date of test: is this the output of interest? that is, timing in relation to symptoms.C. To which eye does this output correspond? Correlate the results with the history and clinical examination. Beware of fields that are mounted incorrectly: the conventional way of mounting is to place the left chart on the right and vice versa, ie, as if the patient is looking into the chart.D. What test was performed? This is particularly important when comparing to any previous tests.a. What degree of visual angle was tested?Most commonly set to 24-2 (central 24 tested with a 54-point grid). A smaller field with higher concentration of points gives further details of the foveal region. For example, 10-2 assesses the central 10 with a 68-point grid. 30-2 is similar to 24-2 but with an additional 6 and with a corresponding increase in the points tested (76-point grid for 30); thus, this is a longer test with the risk of more patient errors.b. Was it a threshold or a screening test?Screening tests use suprathreshold targets of single luminance and in the past were particularly useful because full threshold tests were time consuming. However, SITA threshold tests have superseded these, reducing test times (equivalent to the time taken for screening tests) without losing sensitivity.2. Can I rely on this test?A. False-positive errorsFalse-positive errors identify trigger happy patients who respond in the absence of light stimulus. They are calibrated according to the patient's overall responses, therefore detecting when responses occur too soon after presenting a stimulus is. A false-positive rate of >15% compromises test results.4B. False-negative errorsA false negative is the failure to respond to a relatively bright suprathreshold target in a region that previously responded to fainter stimuli. A high false-negative index may indicate hesitation or inattentiveness, though a true scotoma may also give false-negative results. However, in a true scotoma, the false-negative error rate is low for the contralateral (normal) eye.4 False-negative error may reduce with repeated testing as the patient gets used to the testing procedure.C. Fixation-loss indexFixation loss is tested by presenting a stimulus at the blind spot. If the patient sees this stimulus, it indicates loss of fixation. Values of >20% can compromise the test.4 However, this number could be artefactually elevated if the blind spot was inaccurately located, or in trigger-happy patients. Tracking of the gaze (below) is better for assessing fixation loss.D. Gaze-tracking graphThe eyes are tracked using video. The gaze tracking graph shows an upward spike when the eyes move and a downward spike when the eyes blink.3. Is the test normal?Three maps are generated with numbers and pictorial representations:A. Visual sensitivity mapThe numbers indicate the threshold of stimulus intensity detected in decibel (dB), with zero corresponding to the brightest intensity. Typical normal values centrally are around 30 dB. Values of 40 dB should not appear in standard test conditions but could occur in patients with high false-positive errors. The visual sensitivity may improve with repeat testing as patients become more familiar with it. The grey scale map is a visual representation of the numbers, with darker areas indicating poorer sensitivity to stimuli.B. Total deviation mapThis shows the deviations of the patient's visual sensitivity compared to an age-matched normal population. The numbers indicate the difference compared to the mean, that is, a negative value indicates less visual sensitivity compared to the mean population. The probability plot gives a visual representation of statistical analysis (t test) of this deviation from the mean; the larger departure from the mean, the darker the symbol.C. Pattern deviation mapThis shows the deviation of the pattern from a normal visual hill, where the peak is at the fovea. The numeric values show any departure from the mean of an age-matched population, and as above, the probability plot is a visual representation of statistical analysis indicating the extent of departure from mean. The pattern deviation adjusts for any shifts in overall sensitivity: for example, a patient with cataract might have a smaller or sunken hill but with normal contour patterns.By statistical chance, patients may have a few scattered dark symbols on the probability map, which may not be of concern. Instead, look for patterns, for example, whether these are around the blind spot, which might indicate a true enlargement. It is important to correlate the test results with the history and clinical examination.The visual sensitivity, total deviation and pattern deviation maps should be viewed together for any discrepancies. It is worth noting the following scenarios: Abnormal grey scale on stimulus intensity map but normal probability plots: lid partially obscuring the superior field.Abnormal total deviation but normal pattern deviation: cataract, small pupils, incorrect correction for refractive error.Abnormal pattern deviation but normal total deviation: a test with high false-positive (trigger happy) patient.Additional information that may help, especially when comparing with previous tests, include pupil diameter (is there a wide variation between tests?), lens modification (was the same correction used?), time taken to do the test (was this particularly long?). The global indices show the mean deviations, which can help to monitor progression, especially in glaucoma.Three summary indices appear on the printout4: The visual field index is a staging index designed to correspond to ganglion cell loss, that is, 100% represents normal fields and 0% represents blind fields.The mean deviation represents the degree of departure of the whole field's average values, from age-adjusted normal values.The pattern SD represents irregularities within the field, for example, of localised field defects. This can be small in completely normal patients or in those with complete blindness.The visual field index and the mean deviation can help to identify progression; the visual field index may be less prone to artefacts from cataract. These values may help to monitor progression, but with caution, since artefacts and test reliability can affect them. ConclusionWe present these simplified checklists to help neurologists to interpret Humphrey and Goldmann visual fields. We emphasise the importance of correlating these visual field outputs with careful patient history and clinical examination. Increased exposure to perimetry and its application in the clinical setting will help build up skills in its interpretation. For readers interested in deepening their understanding of fields and its nuances, we suggest further reading from the reference list.46 Key pointsPerimetry results give a pictorial representation of the patient's hill of vision; keep the normal hill in mind when reviewing these tests.Correlate perimetry results with the clinical history and examination (including examination to confrontation), as the tests often have artefacts.Watch out for patient performance effect, for example, high false-positive or false-negative errors, cloverleaf pattern (static perimetry) or spiralling of fields (kinetic fields).Perimetry results change if anything obstructs the travel of light towards the retina (eg cataract).Static and kinetic perimetry complement one another; consider the other if the first is unexpectedly normal or abnormal. ReferencesCooper SA, Metcalfe RA. Assess and interpret the visual fields at the bedside. Pract Neurol 2009;9:32434. doi:10.1136/jnnp.2009.193920OpenUrlAbstract/FREE Full TextHickman SJ. Neurological visual field defects. Neuro-ophthalmology 2011;35:24250. doi:10.3109/01658107.2011.616980OpenUrlBengtsson B, Olsson J, Heijl A, et al. A new generation of algorithms for computerized threshold perimetry, SITA. Acta Ophthalmol Scand 1997;75:36875. doi:10.1111/j.1600-0420.1997.tb00392.xOpenUrlPubMedWeb of ScienceHeijl A, Patella VM, Bengtsoon B. The field analyzer primer: effective perimetry. 2012, Carl Zeiss Meditec.Barton JJS, Benatar M. Field of vision: a manual and atlas of perimetry. Current Clinical Neurology series. New Jersey: Humana Press, 2003.Carl Zeiss Meditec, Inc. Humphrey Field Analyzer Manual Book II-i series system software version 5.1. 2012, Carl Zeiss Meditec. FootnotesContributors SHW wrote the first draft of the manuscript; GTP reviewed and made revisions to the manuscript.Competing interests None declared.Provenance and peer review Commissioned; externally peer reviewed. This paper was reviewed by Mark Lawden, Leicester, UK.
2021 05 25
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2019 Audi A7 to Debut at NAIAS - News.
The all-new 2019 Audi A7 will make its US debut at the North American International Auto Show in Detroit next week. The German luxury automaker is looking to build on the success of the first generation with this new generation of the A7, which the manufacturer claims "exemplifies the prologue design language, featuring a more precise, modern exterior and interior, as well as the next generation of lighting innovations from Audi."Although sedan cars on the whole are finding buyers pretty hard to come by in America and elsewhereat the moment, the Sportback body style of the A7 and others is still proving popular. The combination of a coupe-like silhouette and four doors might not be as overtly practical as that of a similar-size crossover SUV, but it's a look and format where buyersappear happy to accept a little compromise in order to have it. However, Audi is still doing what it can to make this new A7 as practical as possible without ruining its form in any way, as this new model has more interior volume, more comfortable seating for rear seat passengers, and more head and legroom than its predecessor.Interior lighting also seems to be a strong theme with the new A7, with contour lights lining the center console and door trims that precisely trace the cabin's architecture and subtly highlight the increased space. Even the Audi's quattro badge in the instrument panel is illuminated, which some could see as a little gimmicky, but it certainly does add to the theatrical lighting of the cabin.Of course, no new luxury car can hope to make it these days without being awash with the latest and most advanced technology, and the new A7 will feature the same advanced infotainment system that recently made its debut in the A8.
2021 05 25
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Seven Magnificent Castle Stays to Cure Your Royal Family Fever
If you didnt get an invite to the royal baby shower or wedding, dont fret! the global leader in connecting travellers with the widest choice of incredible places to stay, delved into its more than 1.6 million properties in over 128,000 destinations across the globe to present seven magnificent castle stays fit for royalty, but on a commoners budget. nIf you are looking for an ancient castle that has transformed into a charming hotel, then the Castello Di Pavone is the place to stay. Surrounded by a tropical garden, all rooms mix traditional furnishing with modern amenities, offering a truly unique setting steeped in history. The property features a number of dining halls, small and large, and each one has unique features that will you bring you back in time such as chandeliers and beamed ceilings. nWith a magical setting inside a 9th-century castle, the Parador de Cardona is straight out of fairy tale. Offering panoramic views over the Catalonian countryside, and interiors faithful to the Cardona's history with medieval styling, vaulted ceilings, stone walls and gorgeous courtyards, youll be treated like a king or queen. Guests will be spellbound with the delicious and authentic Catalonian specialties, before retreating to a charming bedroom with canopy beds and the beautiful furnishing highlighted by theatrical lighting and rich fabrics. nGiven the iconic Bavarian-style of The Castle Hotel, you might think you were in the hills of Germanys Black Forest. But youre actually only a few steps away from Xinghai Square the largest city square in the world. Offering high-end accommodation and the royal treatment every guest deserves. Surrounded by lush forests, this luxurious property features elegantly decorated rooms and offers the royal treatment at the spa and indoor pool. nSet in the striking woodlands of Galway County with the beautiful backdrop of the 12 Bens Mountain Range, this luxury castle overlooks its impressive salmon fishery on its large private estate. Nature lovers can enjoy a variety of outdoor activities fit for a royal, such as pony trekking, woodcock shooting or just relaxing walk by the lake and the river to admire the local wildlife. nThis impressive castle overlooking the St Brides Bay will transport guests to a mystical time. Dating back to the 12th century, Roch Castle is standing proudly on a rocky outcrop high above the Pembrokeshire landscape. Guests can enjoy a unique sense of history combined with a romantic getaway as each room is luxuriously decorated offering a modern feeling with beautiful views of the British coast and countryside. nSituated in Old Quebec, this heritage property boasts views of the St. Lawrence River and the Old fortified City. Being a landmark on its own right, guests can make themselves at home in the luxurious, European-style rooms as well as spa facilities to relax and rejuvenate after an exciting day exploring upper and lower town districts of Quebec City. nFor something a little less ordinary during your trip in India, choose to rest your head at the RAAS Devigarh. Housed in an 18th-century palace in the village of Delwara, this heritage property is nestled amidst the Aravalli Hills and has a picture-perfect mountain backdrop. Guests can have a quiet read in the library or relax in their spacious suite adorned with grand furnishings and intricately carved archways.
2021 05 25
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