David A. Leske

Telemedicine approach to screening for severe retinopathy of prematurity: a pilot study

PURPOSE To evaluate the use of remote reading of digital retinal photographs in the diagnosis of severe (referral-warranted) retinopathy of prematurity (ROP) during longitudinal screening for ROP. STUDY DESIGN Prospective, longitudinal cohort study. SUBJECTS Forty-four consecutive premature infants at risk for ROP. METHODS All infants were examined longitudinally, over a series of examinations, by indirect ophthalmoscopy (gold standard) and digital photography using the RetCam-120 Digital Retinal Camera (Massie Research Laboratories Inc., Dublin, CA) equipped with an ROP lens. Images were stored and read remotely by a masked reader. Referral-warranted ROP was defined as ROP in zone 1, the presence of plus disease or the presence of any stage 3 ROP. We determined whether and when referral-warranted ROP was diagnosed for each eye, of each infant, on each examination, during the course of each of the infants screening. RESULTS Severe (referral-warranted) ROP was diagnosed in 23 eyes by indirect ophthalmoscopy during their series of examinations. Digital photography had a sensitivity of 100% and a specificity of 96% in detecting referral-warranted ROP. The positive predictive value of digital photography was 92%, and the negative predictive value was 100%. In 87% of eyes, referral-warranted ROP was diagnosed by digital photography before or at the same time as indirect ophthalmoscopy. CONCLUSIONS Longitudinal remote reading of digital photographs using the RetCam-120 system has excellent specificity and sensitivity in detecting referral-warranted ROP. This pilot study has shown that remote reading of digital photographs has promise for telemedicine strategies in ROP screening.

Development of a Quality-of-Life Questionnaire for Adults with Strabismus

PURPOSE We report the development of a patient-derived, health-related quality-of-life (HRQOL) questionnaire for adults with strabismus. DESIGN Cross-sectional study. PARTICIPANTS Twenty-nine patients with strabismus in a first phase, and 32 patients with strabismus, 18 patients with other eye diseases, and 13 visually normal adults in a second phase. METHODS Individual patient interviews generated 181 questionnaire items. For item reduction, we asked 29 patients with strabismus to complete the 181-item questionnaire, analyzed responses, and performed factor analysis. Two prominent factors were identified, and the 10 items with the highest correlation with each factor were selected. The final 20-item questionnaire (10 psychosocial items and 10 function items) was administered to an additional 32 patients with strabismus (22 with diplopia, 10 without diplopia), 13 visually normal adults, and 18 patients with other eye diseases. A 5-point Likert-type scale was used for responses (never = 100, rarely = 75, sometimes = 50, often = 25, and always = 0). Median overall questionnaire scores and psychosocial and function subscale scores, ranging from 0 (worst HRQOL) to 100 (best HRQOL), were compared across groups. MAIN OUTCOME MEASURES The HRQOL questionnaire response scores. RESULTS Median overall scores were statistically significantly lower (worse quality of life) for patients with strabismus (56) compared with visually normal adults (95; P<0.001) and patients with other eye diseases (86; P<0.001). Median scores on the psychosocial subscale were significantly lower for strabismus patients (69) compared with visually normal adults (99; P<0.001) and patients with other eye diseases (94; P<0.001). For the function subscale, median scores were again significantly lower for strabismus patients (43) compared with visually normal adults (91; P<0.001) and patients with other eye diseases (78; P<0.001). CONCLUSIONS We have developed a 20-item, patient-derived, HRQOL questionnaire specific for adults with strabismus, with subscales to assess psychosocial and function concerns. This 20-item, condition-specific questionnaire will be useful for assessing HRQOL in individual strabismus patients and also as an outcome measure for clinical trials. FINANCIAL DISCLOSURE(S) The authors have no proprietary or commercial interest in any materials discussed in this article.

Botulinum toxin treatment versus conservative management in acute traumatic sixth nerve palsy or paresis

PURPOSE Botulinum toxin (BTX), injected into the ipsilateral medial rectus muscle, has been advocated for the management of acute traumatic sixth nerve palsy or paresis. We conducted a multicenter, nonrandomized, data collection study to evaluate recovery rates of patients treated with either conservative measures or BTX. METHODS All members of the American Association for Pediatric Ophthalmology and Strabismus and the North American Neuro-Ophthalmology Society were invited to enroll patients with acute traumatic sixth nerve palsy or paresis during a 2-year period (between March 1996 and February 1998). The BTX group was defined as patients who received a BTX injection within 3 months of injury. Recovery at 6 months from injury was defined as absence of diplopia in the primary position and a distance esotropia of no more than 10 PD in the primary position. Nonrecovered patients with less than 6 months of follow-up (n = 15) were excluded. RESULTS Eighty-four eligible patients were enrolled by 46 investigators. Sixty-two patients (74%) were treated conservatively and 22 (26%) with BTX. Sixty-two patients (74%) had unilateral palsy, and 22 (26%) had bilateral palsy. Recovery rates were similar between BTX and conservatively treated patients (overall: 73% vs 71%, P = 1.0; unilateral: 81% vs 83%, P = 1.0; bilateral: 50% vs 38%, P = 0.66, respectively). CONCLUSIONS In this prospective multicenter study of acute traumatic sixth nerve palsy or paresis, patients treated with either BTX or conservative measures had similar high recovery rates.

A randomized trial comparing Bangerter filters and patching for the treatment of moderate amblyopia in children.

OBJECTIVE To determine whether visual acuity improvement with Bangerter filters is similar to improvement with patching as initial therapy for children with moderate amblyopia. DESIGN Randomized, clinical trial. PARTICIPANTS We enrolled 186 children, 3 to <10 years old, with moderate amblyopia (20/40-20/80). METHODS Children were randomly assigned to receive either daily patching or to use a Bangerter filter on the spectacle lens in front of the fellow eye. Study visits were scheduled at 6, 12, 18, and 24 weeks. MAIN OUTCOME MEASURES Visual acuity in amblyopic eyes at 24 weeks. RESULTS At 24 weeks, amblyopic eye improvement averaged 1.9 lines in the Bangerter group and 2.3 lines in the patching group (difference in mean visual acuities between groups adjusted for baseline acuity = 0.38 line). The upper limit of a 1-sided 95% confidence interval was 0.76 line, which slightly exceeded a prespecified noninferiority limit of <0.75 line. Similar percentages of subjects in each group improved > or =3 lines (Bangerter group 38% vs patching group 35%; P = 0.61) or had > or =20/25 amblyopic eye acuity (36% vs 31%, respectively; P = 0.86). There was a lower treatment burden in the Bangerter group as measured with the Amblyopia Treatment Index. With Bangerter filters, neither a fixation switch to the amblyopic eye nor induced blurring in the fellow eye to worse than that of the amblyopic eye was required for visual acuity improvement. CONCLUSIONS Because the average difference in visual acuity improvement between Bangerter filters and patching was less than half a line, and there was lower burden of treatment on the child and family, Bangerter filter treatment is a reasonable option to consider for initial treatment of moderate amblyopia.

Birth prevalence of visually significant infantile cataract in a defined U.S. population.

Purpose To determine the birth prevalence of visually significant infantile cataract, using population-based comprehensive medical record retrieval, in a defined US population. Design Retrospective, population-based, medical record retrieval. Methods We reviewed records of all pediatric patients (0–17 years) coded as cataract during a 20-year period (1978 to 1997) using the resources of the Rochester Epidemiology Project. “Infantile cataract” was defined as a cataract diagnosed within the first year of life. “Possible infantile cataract” was defined as a cataract, diagnosed after the first year in a child born in Olmsted County, where there was no evidence of an acquired traumatic, acquired systemic, or acquired ocular etiology. Visually insignificant cataracts were excluded. Results Ten incident cases of visually significant infantile cataract were identified during the 20-year study period, yielding a birth prevalence of 3.0 per 10,000 live births (95% CI: 1.5–5.6 per 10,000). Five additional cases of visually significant “possible infantile cataract” were identified, diagnosed between the ages of 2 and 8 years. Inclusion of these “possible infantile cataracts” would result in an estimate of overall birth prevalence for visually significant infantile cataract of 4.5 per 10,000 live births (95% CI: 2.5–7.5 per 10,000). Conclusions Using population-based medical record retrieval methods, we estimate the birth prevalence of visually significant infantile cataract to be 3.0 to 4.5 per 10,000. Infantile cataracts are an important cause of visual impairment in children and these data are useful in planning clinical trials and allocating health care resources.

Development and initial validation of quality of life questionnaires for intermittent exotropia

PURPOSE The development and initial validation of patient-derived, health-related quality-of-life (HRQOL) questionnaires for intermittent exotropia (IXT). DESIGN Cross-sectional study. PARTICIPANTS In a development phase, 27 children (age, 2-17 years) with IXT and 1 of their parents. In an initial validation phase, 33 children with IXT and 49 control children (age, 5-17 years), along with 1 parent for each child. Children in the control group had no strabismus or amblyopia. METHODS Individual patient interviews generated 35 items for child and proxy (parental assessment of childs HRQOL) questionnaires and 46 items for a parent questionnaire. To reduce to a feasible number of items, questionnaires were administered to 5- to 17-year-old children with IXT (n = 15) and parents of 2- to 17-year-old children with IXT (n = 27). Responses were analyzed using standard item reduction methodology. Three final derived IXT questionnaires (IXTQ): child, proxy, and parent (12, 12, and 17 items, respectively) were administered to children with IXT and control children and to parents of IXT and control children. Likert-type scales ranging from never (100, best HRQOL) to almost always (0, worst HRQOL) were used. MAIN OUTCOME MEASURES Median scores for IXT and control groups, compared using Wilcoxon tests. RESULTS Median child scores were significantly lower (worse HRQOL) in the IXT group compared with the control group: 85 (quartiles, 73-92) versus 92 (quartiles, 79-96; P = 0.04). Median proxy IXTQ scores were significantly lower for IXT children than controls: 83 (quartiles, 75-94) versus 98 (quartiles, 92-100; P<0.0001). Median parent IXTQ scores also were significantly lower in the IXT group compared with the control group: 68 (quartiles, 56-79) versus 93 (quartiles, 87-99; P<0.0001). CONCLUSIONS A new 3-part patient-derived HRQOL questionnaire for children with IXT and their parents has been developed and validated, comprising child, proxy, and parent questionnaires. These questionnaires detect reduced HRQOL in children with IXT as reported by the children themselves and perceived by their parents (proxy report). Childhood IXT also seems to affect parent HRQOL. The IXTQ HRQOL questionnaires may prove useful in the clinical assessment of IXT and for clinical trials. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Comparison of Quality-of-Life Instruments in Adults with Strabismus

PURPOSE To compare two health-related quality-of-life (HRQOL) questionnaires in adults with strabismus: the new 20-item Adult Strabismus (AS-20) questionnaire (developed specifically for Adult Strabismus) and the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25). DESIGN Cross-sectional study. METHODS Eighty-four adult patients with strabismus (median age, 53 years; range, 18 to 81 years) completed the AS-20 and VFQ-25 HRQOL questionnaires. Patients were categorized as diplopic (n = 65) or nondiplopic (n = 19). Subnormal HRQOL was defined as less than the fifth percentile for adults with no visual impairment. The proportion of patients below normal was compared overall and by diplopia status. RESULTS Overall, more patients scored below normal with the AS-20 than with the VFQ-25 (90% vs 29%; P < .0001). Nondiplopic patients more often were below normal on the AS-20 psychosocial subscale than on the function subscale (95% vs 42%; P = .002), whereas diplopic patients were more often below normal on the function subscale (85% vs 68%; P = .01). On the psychosocial subscale, more nondiplopic than diplopic patients scored below normal (95% vs 68%; P = .01); on the function subscale, more diplopic than nondiplopic patients scored below normal (85% vs 42%; P = .0005). The VFQ-25 seemed to be insensitive to nondiplopic strabismus: no patients scored below normal on composite score and no more than 11% scored below normal on VFQ-25 subscales. Of diplopic patients, 37% scored below normal on VFQ-25 composite score. No more than 38% scored below normal on VFQ-25 subscales. CONCLUSIONS The new AS-20 seems to be more sensitive than the VFQ-25 for detecting reduced HRQOL in Adult Strabismus, and therefore may be a more useful tool for clinical assessment and clinical trials.

Variability of Stereoacuity in Intermittent Exotropia

PURPOSE Distance stereoacuity is used to monitor deterioration of intermittent exotropia (IXT), but variability of stereoacuity has not been studied rigorously. The purpose of this study was to assess the variability of stereoacuity over one day in children with IXT. DESIGN Prospective cohort study. METHODS Twelve children with IXT were recruited. Stereoacuity was assessed using the Frisby Davis Distance test and the Distance Randot test at distance, and the Frisby and Preschool Randot tests at near. Tests were repeated three or four times over the day, with at least two hours between assessments. The main outcome measure was variable stereoacuity defined as a change by two or more log levels between any two time points over the day. RESULTS Variable stereoacuity at distance was found in five (42%) of 12 patients. Four (33%) of 12 patients demonstrated variable results using the Distance Randot test, three of whom also showed variable results using the Frisby Davis Distance test. One patient had variable results using the Frisby Davis Distance test only. Nine (75%) of 12 patients completed near stereoacuity testing; two (22%) of nine showed variable near stereoacuity. Two (22%) of nine showed variable results using the Preschool Randot test, one (11%) of whom also had variable results using the Frisby test. In some cases, stereoacuity changed from measurable stereoacuity on one assessment to nil on another. CONCLUSIONS Nearly half of children with IXT show marked changes in stereoacuity over the course of a single day. When based on isolated measures, an apparent change in distance stereoacuity between visits should be interpreted with caution.

Changes in Health-Related Quality of Life 1 Year Following Strabismus Surgery

PURPOSE To report changes in health-related quality of life (HRQOL) 1 year following strabismus surgery. DESIGN Retrospective cohort study. METHODS Seventy-three adults undergoing strabismus surgery in a single clinical practice completed the Adult Strabismus-20 (AS-20) HRQOL questionnaire preoperatively and at 6 weeks and 1 year postoperatively. All included adults were successfully aligned at 6 weeks postoperatively. Success was defined based on clinical criteria. Change in AS-20 psychosocial and function scores was evaluated as: 1) difference in scores between 6 weeks and 1 year postoperatively and 2) proportions exceeding previously published limits of agreement at 6 weeks and 1 year. RESULTS For patients successfully aligned at both 6 weeks and 1 year (n=51), further improvement in median scores was seen from 6 weeks to 1 year for both the psychosocial scale (83.8 vs 93.8; P<.0001) and the function scale (72.5 vs 77.5; P=.007). Also, a greater proportion exceeded limits of agreement at 1 year than at 6 weeks (psychosocial: 48% vs 30%; P=.007, function: 67% vs 51%; P=.01). For patients who became partial success (n=18) or failure (n=4) at 1 year there was a numerical decrease in scores at 1 year. CONCLUSIONS Adult strabismus patients who remain successfully aligned show continued improvement in both psychosocial and function scores from 6 weeks to 1 year postoperatively, indicating that improvement in HRQOL is long-lasting. Evaluation of HRQOL should be considered when reporting strabismus surgery outcomes in clinical trials, and may prove helpful in assessing outcomes in clinical practice.

Results of ocular dominance testing depend on assessment method

PURPOSE We developed a near ocular dominance test modeled after the distance hole-in-the-card test and assessed both test-retest reliability of four tests of ocular dominance and agreement between tests. METHODS Forty-six subjects aged 18 to 78 years with visual acuity 20/40 or better in each eye were enrolled from a primary care practice. All subjects had normal eye examinations, with the exception of refractive error, and were examined in their habitual correction. Subjects were tested twice each with the distance hole-in-the-card test, new near hole-in-the-card test, near convergence test, and the Pediatric Eye Disease Investigator Group fixation preference test. RESULTS There was excellent test-retest reliability for each ocular dominance test. Nevertheless, there was only moderate to slight agreement between each possible pairing of tests. CONCLUSIONS Results of ocular dominance tests vary depending on both the testing distance and the specific activity performed as part of the testing procedure.