摘要:

Purpose.Most color vision tests require a high level of cognitive ability and as such are problematic for preschool children and multiply challenged individuals. Our goal was to design a color vision test for these groups and evaluate the clinical utility for preschool children.Methods.The University of Waterloo Colored Dot Test (UWCDot) for Color Vision Testing requires the subject to distinguish a colored disc from seven gray discs. The target disc was a Munsell color along the deutan, protan, or tritan confusion line with gray. The first phase estimated the sensitivity and specificity of the test for adults. Thirty-one adults with normal color vision and 21 adults with congenital red-green defects participated. In the second phase, the utility of the UWCDot test for screening preschool children was determined. Subjects were 281 males and 269 females aged 2.5 to 5 years with normal vision. Their color vision was also assessed with the Standard Pseudoisochromatic Plates, Part 1 (SPP1).Results.The sensitivity and specificity of UWCDot for adults approached the values for the desaturated D-15 when subjective responses were scored. Monitoring fixational eye movements produced sensitivity and specificity values that were similar to the anomaloscope. After adjusting the scoring criterion for the preschool children by using the females as a control, 2.9% of the males were identified as red-green deficient, 1.8% were blue-yellow deficient, and 3.2% had an unclassified deficiency. By definition, 1% of the females failed the test. Counting fixational eye movements was not a useful scoring method in the preschool children. Comparisons with SPP1 indicated that the UWCDot uncovers approximately 35% of the individuals with definite red-green color vision defects.Conclusions.Our results indicate that the UWCDot is capable of detecting approximately 35% of the preschool children who have a congenital red-green color vision defect. These individuals are likely to have a more severe deficiency.

ISSN:1040-5488    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To evaluate the reliability of binocular vision measurements used in the classification of convergence insufficiency.Methods.Two examiners tested 20 fifth and sixth graders in a school setting who passed a screening of visual acuity, refraction, and binocularity. The tests, conducted using a standard protocol, consisted of von Graefe near heterophoria (NH), phorometric positive fusional vergence (PFV), nearpoint of convergence (NPC), and monocular pushup accommodative amplitude (AA). Each examiner measured each child three consecutive times for each test, on two separate occasions, spaced approximately 1 week apart. Intraexaminer and interexaminer agreement was assessed using intraclass correlation coefficients (ICC), the median absolute difference (MAD), and the coefficient of repeatability (COR).Results.The within-session reliability of the NH (ICC: 0.95 to 0.99), NPC (ICC: 0.94 to 0.98), and AA (ICC: 0.88 to 0.95) were good, whereas the PFV was less reliable (ICC: 0.71 to 0.94). The intraexaminer reliability between sessions was good for the NPC (ICC: 0.92 and 0.89), less reliable for NH (ICC: 0.81 and 0.81) and AA (ICC: 0.89 and 0.69), and much less reliable for PFV break (ICC: 0.59 and 0.53). Typical between-session PFV differences (MAD) were between 3 and 4 &Dgr;, whereas the COR differences were as large as 12 &Dgr;.Conclusions.Three of the four measures (NH, NPC, and AA) often used in the classification of convergence insufficiency generally have good within-session and between-session reliability. The PFV break was found to have only fair reliability with clinically significant differences between sessions. The large potential test-retest differences found could complicate clinical decision-making in regards to diagnosis and treatment.

ISSN:1040-5488    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To study the effectiveness of pencil pushups treatment (PPT) for the treatment of convergence insufficiency in a clinical situation.Methods.PPT was prescribed for use at home for 6 weeks for 25 subjects with convergence insufficiency.Results.Twelve of the subjects returned for follow-up. Seven of 12 (58%) subjects showed a clinically significant improvement in nearpoint of convergence and positive fusional vergence, and 11 of 12 reported improvement in symptoms. Only one subject became asymptomatic.Conclusions.PPT resulted in some improvement in both objective findings and symptoms for some subjects. Compliance with the recommended home therapy protocol was poor.

ISSN:1040-5488    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Refractive error and accommodative responsivity were monitored at 4-month intervals over a 1-year period to determine whether an increased lag of accommodation either precedes or accompanies the development of myopia. Accommodation was measured for stimulus levels of 2.5, 3, 4, and 5 D, and both the slope of the stimulus-response function and accommodative error were computed. Almost all subjects exhibited accommodative stimulus-response gradients close to unity, although a lower gradient was observed in subjects who were myopic upon entry into the study and whose ametropia remained stable. These stable myopes also exhibited the largest lag of accommodation. These findings do not support the proposal that the development of myopia in young adults is accompanied by a reduced accommodative response during nearwork.

ISSN:1040-5488    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:1040-5488    

出版商:OVID    

年代:2002

数据来源: OVID