A new optotype chart for detection of nonorganic XXXX .

@entity1 @entity227
OBJECTIVE: To develop a new optotype chart for detection of nonorganic decreased vision. DESIGN: Comparative observational case series. @entity1 : Optotype thresholds determination in three normal subjects and testing on 30 consecutive @entity1 with unclear visual acuity loss. METHODS: A new optotype chart was developed, with an optotype minimum angle of resolution that is independent of size. In three normal subjects rank correlation was calculated between the optotype thresholds and the optotype sizes. A pocket chart was tested in a masked manner on 30 consecutive @entity1 referred because of unclear visual acuity loss. MAIN OUTCOME MEASURES: Optotype thresholds and usefulness in clinical routine (positive and negative predictive values including 95% confidence intervals [CI]). RESULTS: The optotype thresholds did not correlate with the optotype sizes. Ten percent (3 of 30) of the @entity1 referred because of unclear visual acuity loss had to be excluded, because their diagnosis remained unclear. All @entity1 (16 of 16) with organic @entity227 saw all optotypes sizes. Eighty-nine percent (10 of 11) of @entity1 with nonorganic @entity227 claimed to see only the larger optotypes. The positive predictive value for nonorganic @entity227 of the new pocket chart was 100% (CI, 74%-100%); the negative predictive value was 94% (CI, 75%-100%). CONCLUSIONS: The new pocket chart seems to be useful for detection of @entity227 caused by nonorganic disease.
