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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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Related in: MedlinePlus

Target locations of the scotopic visual field.The scotopic visual field locations (black) were based on the locations used in the Esterman test (black and grey). The large diamonds represent the locations that were used to determine the homogeneity of the visual field by comparing the average threshold at 7°, 45°, 60°, and 75°.
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pone-0062927-g001: Target locations of the scotopic visual field.The scotopic visual field locations (black) were based on the locations used in the Esterman test (black and grey). The large diamonds represent the locations that were used to determine the homogeneity of the visual field by comparing the average threshold at 7°, 45°, 60°, and 75°.

Mentions: We chose target locations from the Esterman visual field [30], because it is a very wide visual field test. We removed several target locations to keep measurement time acceptable (<15 min). Fig. 1 shows the standard Esterman target locations (grey) and the 36 selected locations (black). To analyse the homogeneity of the threshold across the visual field, we averaged the thresholds of four locations at 7°, 45°, 60° and 75° on the horizontal axes (large black diamonds in Fig. 1).


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)

Target locations of the scotopic visual field.The scotopic visual field locations (black) were based on the locations used in the Esterman test (black and grey). The large diamonds represent the locations that were used to determine the homogeneity of the visual field by comparing the average threshold at 7°, 45°, 60°, and 75°.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3643903&req=5

pone-0062927-g001: Target locations of the scotopic visual field.The scotopic visual field locations (black) were based on the locations used in the Esterman test (black and grey). The large diamonds represent the locations that were used to determine the homogeneity of the visual field by comparing the average threshold at 7°, 45°, 60°, and 75°.
Mentions: We chose target locations from the Esterman visual field [30], because it is a very wide visual field test. We removed several target locations to keep measurement time acceptable (<15 min). Fig. 1 shows the standard Esterman target locations (grey) and the 36 selected locations (black). To analyse the homogeneity of the threshold across the visual field, we averaged the thresholds of four locations at 7°, 45°, 60° and 75° on the horizontal axes (large black diamonds in Fig. 1).

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