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Assessment of night vision problems in patients with congenital stationary night blindness.

Bijveld MM, van Genderen MM, Hoeben FP, Katzin AA, van Nispen RM, Riemslag FC, Kappers AM - PLoS ONE (2013)

Bottom Line: The questionnaire showed that the CSNB2 patients hardly experienced any night vision problems, while all CSNB1 patients experienced some problems although they generally did not describe them as severe.The results from the "2D Light Lab" showed that all CSNB1 patients were blind at low intensities (equal to starlight), but quickly regained vision at higher intensities (full moonlight).From the results we conclude that night vision problems in CSNB, in contrast to what the name suggests, are not conspicuous and generally not disabling.

View Article: PubMed Central - PubMed

Affiliation: Bartiméus Institute for the Visually Impaired, Zeist, The Netherlands. mbijveld@bartimeus.nl

ABSTRACT
Congenital Stationary Night Blindness (CSNB) is a retinal disorder caused by a signal transmission defect between photoreceptors and bipolar cells. CSNB can be subdivided in CSNB2 (rod signal transmission reduced) and CSNB1 (rod signal transmission absent). The present study is the first in which night vision problems are assessed in CSNB patients in a systematic way, with the purpose of improving rehabilitation for these patients. We assessed the night vision problems of 13 CSNB2 patients and 9 CSNB1 patients by means of a questionnaire on low luminance situations. We furthermore investigated their dark adapted visual functions by the Goldmann Weekers dark adaptation curve, a dark adapted static visual field, and a two-dimensional version of the "Light Lab". In the latter test, a digital image of a living room with objects was projected on a screen. While increasing the luminance of the image, we asked the patients to report on detection and recognition of objects. The questionnaire showed that the CSNB2 patients hardly experienced any night vision problems, while all CSNB1 patients experienced some problems although they generally did not describe them as severe. The three scotopic tests showed minimally to moderately decreased dark adapted visual functions in the CSNB2 patients, with differences between patients. In contrast, the dark adapted visual functions of the CSNB1 patients were more severely affected, but showed almost no differences between patients. The results from the "2D Light Lab" showed that all CSNB1 patients were blind at low intensities (equal to starlight), but quickly regained vision at higher intensities (full moonlight). Just above their dark adapted thresholds both CSNB1 and CSNB2 patients had normal visual fields. From the results we conclude that night vision problems in CSNB, in contrast to what the name suggests, are not conspicuous and generally not disabling.

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The constructed image of a living room used in the 2D Light Lab.The image contained 22 everyday objects that varied in size, colour and contrast. The objects were (from left to right and top to bottom): small television, alarm clock, table-lamp, armchair, trashcan, cupboard, bench, coat hanger, vase, plant, playing card, mug, dark table, pencil, white table, telephone, chair, pair of gloves, newspaper, hammer, screwdriver and watch. The left image (A) shows the image at full intensity, the right image (B) shows the image at a low intensity.
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pone-0062927-g002: The constructed image of a living room used in the 2D Light Lab.The image contained 22 everyday objects that varied in size, colour and contrast. The objects were (from left to right and top to bottom): small television, alarm clock, table-lamp, armchair, trashcan, cupboard, bench, coat hanger, vase, plant, playing card, mug, dark table, pencil, white table, telephone, chair, pair of gloves, newspaper, hammer, screwdriver and watch. The left image (A) shows the image at full intensity, the right image (B) shows the image at a low intensity.

Mentions: The two dimensional (2D) Light Lab was derived from the original three dimensional (3D) Light Lab [31] which consists of a real living room filled with daily objects. In the 3D Light Lab, patients are asked to describe the objects they detect and recognize at increasing light levels. The 2D Light Lab consisted of an image of a living room that was projected on a screen. The image used in these experiments was constructed from separate photo’s using photo-editing software (Corell Paintshop Photo Pro X3), which made it easier to control intensity and contrast. The image, shown in Fig. 2, contained 22 everyday objects that varied in size and colour. The distance between screen (4∶3, 2.40 m, Projecta) and projector (Sanyo PLC-XP100L, 3LCD, XGA) was 4 m. The subject sat on a chair 4 m from the screen, at an angle of 10° from the midline between projector and screen. Apart from the light from the screen, the room was completely dark. We used a retro reflective screen with a directed reflectivity a factor 2.4 larger than that of a standard white screen, so that the luminance in the direction of the projector was high, but indirect light scattering from the walls was minimized.


Assessment of night vision problems in patients with congenital stationary night blindness.

Bijveld MM, van Genderen MM, Hoeben FP, Katzin AA, van Nispen RM, Riemslag FC, Kappers AM - PLoS ONE (2013)

The constructed image of a living room used in the 2D Light Lab.The image contained 22 everyday objects that varied in size, colour and contrast. The objects were (from left to right and top to bottom): small television, alarm clock, table-lamp, armchair, trashcan, cupboard, bench, coat hanger, vase, plant, playing card, mug, dark table, pencil, white table, telephone, chair, pair of gloves, newspaper, hammer, screwdriver and watch. The left image (A) shows the image at full intensity, the right image (B) shows the image at a low intensity.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3643903&req=5

pone-0062927-g002: The constructed image of a living room used in the 2D Light Lab.The image contained 22 everyday objects that varied in size, colour and contrast. The objects were (from left to right and top to bottom): small television, alarm clock, table-lamp, armchair, trashcan, cupboard, bench, coat hanger, vase, plant, playing card, mug, dark table, pencil, white table, telephone, chair, pair of gloves, newspaper, hammer, screwdriver and watch. The left image (A) shows the image at full intensity, the right image (B) shows the image at a low intensity.
Mentions: The two dimensional (2D) Light Lab was derived from the original three dimensional (3D) Light Lab [31] which consists of a real living room filled with daily objects. In the 3D Light Lab, patients are asked to describe the objects they detect and recognize at increasing light levels. The 2D Light Lab consisted of an image of a living room that was projected on a screen. The image used in these experiments was constructed from separate photo’s using photo-editing software (Corell Paintshop Photo Pro X3), which made it easier to control intensity and contrast. The image, shown in Fig. 2, contained 22 everyday objects that varied in size and colour. The distance between screen (4∶3, 2.40 m, Projecta) and projector (Sanyo PLC-XP100L, 3LCD, XGA) was 4 m. The subject sat on a chair 4 m from the screen, at an angle of 10° from the midline between projector and screen. Apart from the light from the screen, the room was completely dark. We used a retro reflective screen with a directed reflectivity a factor 2.4 larger than that of a standard white screen, so that the luminance in the direction of the projector was high, but indirect light scattering from the walls was minimized.

Bottom Line: The questionnaire showed that the CSNB2 patients hardly experienced any night vision problems, while all CSNB1 patients experienced some problems although they generally did not describe them as severe.The results from the "2D Light Lab" showed that all CSNB1 patients were blind at low intensities (equal to starlight), but quickly regained vision at higher intensities (full moonlight).From the results we conclude that night vision problems in CSNB, in contrast to what the name suggests, are not conspicuous and generally not disabling.

View Article: PubMed Central - PubMed

Affiliation: Bartiméus Institute for the Visually Impaired, Zeist, The Netherlands. mbijveld@bartimeus.nl

ABSTRACT
Congenital Stationary Night Blindness (CSNB) is a retinal disorder caused by a signal transmission defect between photoreceptors and bipolar cells. CSNB can be subdivided in CSNB2 (rod signal transmission reduced) and CSNB1 (rod signal transmission absent). The present study is the first in which night vision problems are assessed in CSNB patients in a systematic way, with the purpose of improving rehabilitation for these patients. We assessed the night vision problems of 13 CSNB2 patients and 9 CSNB1 patients by means of a questionnaire on low luminance situations. We furthermore investigated their dark adapted visual functions by the Goldmann Weekers dark adaptation curve, a dark adapted static visual field, and a two-dimensional version of the "Light Lab". In the latter test, a digital image of a living room with objects was projected on a screen. While increasing the luminance of the image, we asked the patients to report on detection and recognition of objects. The questionnaire showed that the CSNB2 patients hardly experienced any night vision problems, while all CSNB1 patients experienced some problems although they generally did not describe them as severe. The three scotopic tests showed minimally to moderately decreased dark adapted visual functions in the CSNB2 patients, with differences between patients. In contrast, the dark adapted visual functions of the CSNB1 patients were more severely affected, but showed almost no differences between patients. The results from the "2D Light Lab" showed that all CSNB1 patients were blind at low intensities (equal to starlight), but quickly regained vision at higher intensities (full moonlight). Just above their dark adapted thresholds both CSNB1 and CSNB2 patients had normal visual fields. From the results we conclude that night vision problems in CSNB, in contrast to what the name suggests, are not conspicuous and generally not disabling.

Show MeSH
Related in: MedlinePlus