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David R Stager

Publications and source records attributed to David R Stager.

At least 19 recordsLinked to original sources

The Amblyopia and Strabismus Questionnaire: English translation, validation, and subscales.

PURPOSE: To establish the English-language version of the Amblyopia and Strabismus Questionnaire (ASQE). DESIGN: Prospective cohort study. METHODS: A structured translation process was followed to generate the ASQE, a 26-item instrument (originally in Dutch) containing five subscales for fear of losing the better eye, distance estimation, visual disorientation, double vision, and social contact and appearance. The ASQE was administered to 150 adults in a private practice setting. All had strabismus with or without amblyopia and visual acuity of 20/50 or better in at least one eye. Subjects also completed a brief disability questionnaire, and they were further characterized by levels of unilateral vision loss, diplopia, and asthenopia. RESULTS: ASQE scores were highly correlated with the disability questionnaire outcomes (r = -.76, P < .0001). Internal consistency reliability (Cronbach alpha) of the subscales ranged from 0.80 to 0.92. Strong correlations were found between clinical characteristics and the ASQE (total score and subscale scores). CONCLUSIONS: The ASQE showed good psychometric properties that are in line with those of the original instrument. This, combined with strong correlations between ASQE scores and clinical characterization of the participants, establishes the ASQE as a useful tool for use in populations with strabismus and/or amblyopia.

Adolescent↗

The effectiveness of Nd:YAG laser capsulotomy for the treatment of posterior capsule opacification in children with acrylic intraocular lenses.

INTRODUCTION: Acrylic intraolcular lenses (IOLs) may result in lower rates of posterior capsular opacification (PCO) than poly(methyl methacrylate) lenses in children. Nonetheless, PCO frequently occurs eventually, especially in younger children. Here, we evaluated the success of neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy for the management of PCO after acrylic IOL implantation without primary capsulectomy. METHODS: We reviewed 73 eyes in 57 children (age 23 months to 12 years; median, 6.4 years) who underwent Nd:YAG laser capsulotomy after AcrySof IOL implantation and who had at least 3 months follow-up (range, 3-92 months; median, 25 months). The effectiveness of laser treatment was evaluated in terms of the need for repeat laser procedures or intraocular surgery to clear the visual axis. RESULTS: Fifty-one eyes (70%) maintained a clear visual axis after a single Nd:YAG procedure, 10 eyes (84% cumulative) after 2 Nd:YAG procedures, and another 3 eyes (88% cumulative) after 3 Nd:YAG procedures. Six eyes (8%) required pars plana membrane removal to clear the visual axis, whereas 3 eyes (4%) continue to need treatment. Life table analysis showed that the probability of continuing success after 24 months with a single Nd:YAG procedure is 68% (95% confidence interval 53-83%). In younger children (age<4 years), this rate probability was lower than in older children (35% vs. 74%; P=0.022). Two eyes developed mild transient elevated intraocular pressure. In 1 eye, the IOL was dislocated and replaced. DISCUSSION: Nd:YAG laser capsulotomy is an acceptable option for the management of PCO after AcrySof IOL implantation in children and produces complications infrequently.

Acrylic Resins↗

The cost utility of strabismus surgery in adults.

PURPOSE: Cost-utility analysis evaluates the cost of medical care in relation to the gain in quality-adjusted life years (QALYs). Our purpose was to develop a cost model for surgical care for adult strabismus, to estimate the mean cost per case, to determine the associated gain in QALYs, and to perform cost-utility analysis. METHODS: A cost model incorporated surgery, pre- and postoperative care, and a mean of 1.5 procedures per patient. The gain in QALYs was based on the improvement of utility on a scale from 0 (death) to 1 (perfect health). Utility was measured through physician-conducted interviews employing a time tradeoff question (seeking to estimate the portion of life expectancy a patient would be willing to trade for being rid of disease and associated effects). The interviews were conducted before and 5 to 8 weeks after surgery in 35 strabismic patients (age 19-75 years). RESULTS: The cost model resulted in an estimated total cost of 4,254 dollars per case. A significant improvement of utility was found: 0.96 +/- 0.11 postoperatively versus 0.85 +/- 0.20 preoperatively (p = 0.00008). Based on the mean life expectancy (36.0 years) of these patients, and discounting outcomes and costs by 3% annually, this resulted in a mean value gain of 2.61 QALYs after surgery and a cost-utility for strabismus surgery of 1,632 dollas/QALY. CONCLUSIONS: In the United States, treatments <50,000 dollars/QALY are generally considered "very cost-effective." Strabismus surgery in adults falls well within this range.

Adult↗

Long-term motor and sensory outcomes after early surgery for infantile esotropia.

PURPOSE: The proper timing of surgery for infantile esotropia remains controversial. Early surgery may yield better sensory outcomes whereas later surgery may result in better alignment. Several recent studies reported promising sensory outcomes in small groups of children that underwent surgery by 6 months of age. Here, we present motor and sensory outcomes of a cohort of 50 consecutive children enrolled in a prospective study who had surgery by 6 months of age and were followed for 4-17 years. METHODS: Angle of deviation, subsequent surgeries, treatment with spectacles, amblyopia, fusion, and stereopsis were evaluated during follow-up. Outcomes from the early surgery group were compared with a concurrently recruited cohort who had surgery at 7-12 months (n=78). RESULTS: On the initial visit, both cohorts had the same median angle of deviation (45(Delta)) and similar refractive error; the median angle of deviation increased by the final preop visit (55(Delta)). Postoperatively, both cohorts had alignment within 6(Delta) in 83-94% of cases on all visits. Both cohorts had similar rates of additional surgery, and 44-48% wore hyperopic correction postoperatively. Compared with the 7- to 12-month cohort, more children in the early-surgery cohort had peripheral fusion (78% vs 61%; p < 0.02), central fusion (15% vs 2%; p < 0.01), Randot stereopsis (38% vs 16%; p < 0.003), and Randot stereoacuity of 200 seconds or better (20% vs 9%; p < 0.05). CONCLUSIONS: Early surgery was associated with a higher prevalence of fusion and stereopsis, without adverse motor outcomes.

Depth Perception↗

Reasons for delay of surgical intervention in adult strabismus.

BACKGROUND: It has been our impression that adult patients with strabismus frequently delay surgical intervention. OBJECTIVES: To determine the length of time adult patients waited before undergoing strabismus surgery and to determine the reasons why these delays occurred. DESIGN, SETTING, AND PARTICIPANTS: Prospective survey of consecutive patients who delayed strabismus surgery for more than 1 year. INTERVENTION: Preoperative survey. MAIN OUTCOME MEASURES: The primary outcome measure was time between the onset of strabismus and surgery and the reason why surgery had not been previously sought. RESULTS: The mean age among 128 study participants was 45.7 years (age range, 18-86 years). The mean time between the onset of current strabismus and surgery was 19.9 years (range, 1-72 years). The major reasons for delay in seeking surgical treatment included the following: surgery was never offered by eye care specialist (35 patients [27%]), surgery was offered but declined by the patient (29 patients [23%]), the patient had received prior satisfactory nonsurgical care (17 patients [13%]), the patient had never sought care (14 patients [11%]), the patient had a previous poor surgical experience (8 patients [6%]), and the patient had been told by their eye specialist that nothing could be done or that surgery could make them worse (8 patients [6%]). CONCLUSIONS: Strabismus surgery is often delayed for many years in adult patients who could potentially benefit from it. Almost half of such delays could be avoided by better education of the lay public and the medical community.

Adolescent↗

The management of strabismus in adults--II. Patient and provider perspectives on the severity of adult strabismus and on outcome contributors.

PURPOSE: As part of a larger study intended to evaluate the management of strabismus in adults, we documented and compared patient and provider perspectives on the various factors that may contribute to treatment outcome and value of strabismus care. METHODS: By completing a questionnaire, 170 patients with strabismus (ages 19 to 87 years) and 11 strabismus specialists who performed surgery on these patients each indicated the relative weight of several disease- and treatment-related contributors to the outcome and value of care. In addition, each respondent rated the severity of the strabismus before and after surgery. RESULTS: Overall severity ratings improved as a result of surgery. The improvement perceived by the physicians was 5.1 +/- 1.7 on a 10-point scale and was larger than the 2.6 +/- 3.6 points improvement perceived by the patients ( P < 0.001). Patients and physicians expressed different views on the relative contributions to outcome and value (overall P < 0.001). Both groups indicated "the condition," "the physician," and "the procedures" as the largest contributors, but "condition" was perceived as more important by the physicians than by the patients ( P < 0.001), and "physician" was more important to the patients than to the physicians ( P < 0.001). CONCLUSION: Although in approximate agreement on the main contributors to outcome and value, discrepancies exist between perspectives of patients and physicians on the relative weights of those contributors. Public information, education, and counseling may bring these perspectives better in line and ultimately improve both quality and patient satisfaction.

Adult↗

The management of strabismus in adults--III. The effects on disability.

INTRODUCTION: This is the third article in a series on the various facets of the management of strabismus in adults. Here, we give a broad overview of the types and severity of disability and provide initial validation of an instrument (questionnaire) to assess these disability aspects. METHODS: After undergoing strabismus surgery, 101 patients from 6 centers completed a 6-item questionnaire in which they rated both the before-surgery and after-surgery severity of problems associated with their strabismus, ranging from specific health, daily functioning, social interaction, concerns about the future, and self-image to job-related difficulties. RESULTS: The before-surgery outcomes showed significant variation across the 6 types of problems (P < 0.001), with "specific health" and "daily tasks" yielding the highest problem rating. Patients with diplopia reported more severe problems with "daily tasks" (P = 0.004) and "concerns about the future" (P = 0.026) than patients without diplopia. Overall, all problem ratings declined after surgery (P < 0.001), but patients who were not successfully aligned were left with higher problem ratings on "specific health" (P = 0.005), "daily tasks" (P = 0.003), and "social interaction" (P = 0.024). CONCLUSIONS: The results indicate a wide range of disability aspects in adult patients with strabismus, with moderate differences between patients with or without diplopia. Improvements in disability after surgery, as reflected by these ratings, should be taken into account when assessing the health value of adult strabismus management.

Adult↗

Visual acuity development after the implantation of unilateral intraocular lenses in infants and young children.

PURPOSE: Intraocular lenses (IOLs) are now being implanted in infants and children with unilateral cataracts. However, there are no prospective data on the development of visual acuity after implantation. The aim of the present study was to prospectively assess the development of acuity in infants and preschool children who received IOLs or aphakic contacts lenses (CLs) after the extraction of a unilateral cataract. METHODS: Visual acuity was assessed using Teller Acuity Cards and/or crowded HOTV tests at target ages of 6 months, 1, 2, 3, and 4 years. RESULTS: Infants who received a primary IOL after extraction of dense congenital unilateral cataract (n = 5) showed improvement from an initially low mean visual acuity of 20/170 at 6 months to 20/85 at 12 months and 20/54 at 4 years. Visual acuity in the IOL group was similar to that of children who had good-to-excellent compliance with CL wear (n = 36; 4-year visual acuity 20/50) and better than that of children who had moderate-to-poor compliance (n = 11; 4-year visual acuity 20/135). Children who received IOLs after extraction of developmental unilateral cataracts by 6 months (n = 4; 4-year visual acuity 20/55) had visual acuity development similar to those treated with CLs (n = 5; 4-year visual acuity 20/55). Children who received IOLs after extraction of developmental unilateral cataracts after 1 year of age (n = 18) had better visual acuity than children those treated with CLs (n = 4) at 4 years of age (20/40 vs. 20/135). CONCLUSION: IOLs and aphakic CLs support similar visual acuity development after surgery for a unilateral cataract. IOLs may support better visual acuity development when compliance with CL wear is moderate to poor or when a cataract is extracted after 1 year of age.

Aphakia, Postcataract↗

Screening for amblyopia in preverbal children with photoscreening photographs: IV. Interobserver variability in photograph grading: origin and method of reduction.

BACKGROUND: Earlier detection of childhood vision disorders is a prominent goal of vision screening. The Medical Technology and Innovation (MTI) PhotoScreener addresses this objective. Use of this camera does not require verbal feedback and may be administered early in a child's development. Decreasing the variability in photograph grading results will boost the utility of any photoscreening system. This report aims to understand and to decrease intra- and inter-observer variability in grading photoscreening photographs. METHODS: We dissected the photograph grading process and quantified the intra- and inter-observer agreement using intraclass plot correlation coefficients. We evaluated the outcome of a two grader verification system vs. adjudicated measurements with Receiver Operator Characteristic (ROC) curves. PARTICIPANTS: Data on 955 children under 5 years of age, normal except for refractive error, each with complete photoscreening and eye examination data, culled from two previous studies. MAIN OUTCOME MEASURES: Intra- and inter-observer agreement in measuring bright crescent dimensions and pupillary diameters. Sensitivity and specificity of detection of hyperopia. RESULTS: Measurements of bright crescents are associated with greater variability than are measurements of pupillary diameters. Recognition and omission of light "rim" measurements from photograph grading will result in superior inter-observer agreement. Photograph independent errors increase variability and may be corrected by remeasurement. A verification system in which the most discrepant 5% of measurements are redone results in ROC curves similar to adjudicated dimension. CONCLUSIONS: We conclude: 1) two novices grading photographs can do as well as one expert in most cases; 2) the proposed grading methodology has undergone statistical validation and can be used in other areas of ophthalmology and medicine; and 3) inter-observer variability, one of the limitations of photoscreening photograph grading, can be reduced. For 95% of the photographs, two novices achieve similar true positive and true negative values with or without adjudication.

Amblyopia↗

The utility of strabismus in adults.

PURPOSE: To determine the utility (quality-of-life weight) associated with adult strabismus. METHODS: Time tradeoff utility values were measured in physician-conducted interviews with 140 adult patients with strabismus in a private practice setting. Patients also completed a questionnaire containing six items that rated the following aspects of disability: specific health problems, problems with tasks of daily living, problems with social interaction, self-image problems, concerns about the future, and job-related problems. Patients were characterized as presurgical or nonsurgical, and their diplopia and asthenopia were rated by the physician on a four-level scale. RESULTS: About 60% of all patients indicated willingness to trade part of their life expectancy in return for being rid of strabismus and its associated effects. The median utility was 0.93 (interquartile range, 0.83 to 1.0). A significantly smaller proportion (44%) of the nonsurgical patients (N = 41) appeared willing to trade time compared with surgical patients (68%; P = .009). Median utility in the presurgical patients was 0.90. Strong relationships were found between utility and the level of diplopia (P < .0001), and between utility and the level of asthenopia (P < .0001). Utility was correlated with all six disability ratings (all P < or = .00062). CONCLUSION: A majority of the patients interviewed would trade a portion of their life expectancy in return for being rid of strabismus and its associated effects. These results were validated by significant associations with diplopia, asthenopia, and disability.

Activities of Daily Living↗

Development of an instrument to assess vision-related quality of life in young children.

PURPOSE: Quality of life (QOL) instruments are increasingly utilized in ophthalmological research. Measuring vision-related QOL in young children is complicated by constantly evolving abilities related to normal growth and development. Our aim was to develop vision-related QOL instruments for children in different age ranges <==7 years, and to provide initial validation of these instruments. DESIGN: Cross-sectional study. METHODS SETTING: Multicenter. PATIENTS: 773 pediatric patients (age <==7 years) with a wide range of ophthalmological diagnoses. PROCEDURE: Questionnaire. A 61-item prototype instrument with a wide variety of items was applied to 403 consecutive patients. The usefulness of items was evaluated as a function of age in order to derive two age-group specific instruments and to find the age limit dividing the age groups. Thus, age-specific versions of a Children's Visual Function Questionnaire (CVFQ) were defined for ages <3 years and >/=3 years, and applied to a convenience sample of patients. OUTCOME: Subscale scores. Factor analysis helped identify underlying dimensions of the data, and corresponding subscales were defined. Validation was provided by examining the internal consistency reliability and by exploring the associations between scores and clinical characteristics. RESULTS: Subscales for General health, General vision, Competence, Personality, Family impact, and Treatment were defined, with internal consistency reliabilities ranging from 0.60 to 0.86. The association between subscales scores and age was weak, whereas strong correlations were found with the level of visual impairment and type of visual diagnosis. CONCLUSION: The CVFQ assesses the impact of visual impairment on children and their families, and is expected to become a useful tool for the pediatric vision research community.

Child↗

Factors influencing stereoacuity outcomes in adults with acquired strabismus.

PURPOSE: Functional improvements of binocular vision after strabismus surgery in adults are common but not well understood. In a prospective study, factors associated with stereoacuity outcome in patients with strabismus acquired following binocular vision maturation were investigated. DESIGN: Prospective data collection. METHODS: Twenty-three patients aged 14 to 85 years with acquired strabismus were enrolled. Random dot stereoacuity was quantified using a battery of tests including the Randot Preschool Stereoacuity test, the Randot (version 2) shapes test, and the Randot Butterfly test. RESULTS: Ninety-six percent of patients achieved measurable stereoacuity following successful eye realignment. Better median stereoacuity is achieved in patients with the following characteristics: < or =12 months of constant strabismus (60 vs 400 seconds of arc with >12 months' strabismus, P < .001); a presurgical capacity for fine to moderate stereopsis (60 vs 400 seconds of arc with coarse or no measurable stereopsis, P < .005); a presurgical capacity for macular fusion (60 vs 400 seconds of arc with no measurable macular fusion capacity, P < .001); and postsurgical orthotropia (100 seconds of arc) or intermittent orthotropia (100 seconds of arc vs 2000 seconds of arc with 5 to 8 prism diopters (PD) of postsurgical residual strabismus, P < .05). CONCLUSION: Surgical correction of acquired strabismus is associated with recovery of stereopsis. Factors associated with stereoacuity outcomes include duration of strabismus and presurgical binocular vision capacity. A postsurgical correction of orthotropia or intermittent orthotropia supports better stereoacuity than a larger residual angle of strabismus subtending up to 8 PD of deviation.

Adolescent↗

Pre-operative stability of infantile esotropia and post-operative outcome.

PURPOSE: To define the prevalence and time course of significant changes in angle of deviation during the first months after the diagnosis of infantile esotropia and to determine whether long-term alignment and sensory outcomes differ when surgical alignment is performed on infants with stable vs unstable angles of deviation. DESIGN: Prospective cohort study. METHODS: setting: Institutional and clinical practice. patient population: Newly diagnosed patients with infantile esotropia (N = 208). observation procedure: Preoperative measurements of the angle of deviation on the initial visit and at approximate six-week intervals until surgery was performed. main outcome measures: Ocular alignment at six weeks, one year, and four years postoperative and stereoacuity at age five to nine years. RESULTS: Overall, 57% of infants had an esodeviation on the second visit that was within 10 prism diopters (p.d.) of the deviation measured on the initial visit (stable group), 33% had an increase of 10 p.d. or more (unstable group), and 11% had a decrease of 10 p.d. or more. Among the 127 patients with additional preoperative visits, many switched between the stable and unstable categories during follow-up. Long-term, stable and unstable preoperative alignment groups had similar postoperative motor alignment, re-operation rates, rates of prescription of hyperopic, or bifocal spectacle correction and stereoacuity. CONCLUSIONS: It may not be necessary to wait for a "stable" angle of esodeviation before surgery since both alignment and sensory outcomes were similar for stable and unstable groups.

Age of Onset↗

Stereopsis and long-term stability of alignment in esotropia.

PURPOSE: Recent studies of infantile and accommodative esotropia (ET) have focused on stereoacuity as a final outcome measurement for judging the success or failure of treatment. The purpose of the present study was to extend this approach by evaluating whether the presence of stereopsis developing immediately after surgical alignment or optical correction plays a role in maintenance of long-term alignment. METHODS: Random-dot stereoacuity was assessed within 3 months of initial surgical alignment in 70 children with infantile ET and within 3 months of initial optical correction in 66 children with accommodative ET. At > or = 5 years of age, adverse outcomes were assessed including loss of alignment, amblyopia, and nil stereopsis. Risk-factor analysis was used to evaluate whether early nil stereopsis increased the risk for subsequent adverse outcomes. RESULTS: In the infantile ET cohort, early nil stereopsis was associated with a 3.6 times (95% confidence interval [CI] 2.4 to 4.1) greater risk of surgery for recurrent ET or consecutive exotropia and a 4.2 times (95% CI 3.3 to 4.4) greater risk for nil stereopsis at > or = 5 years of age. In the accommodative ET cohort, early nil stereopsis was associated with a 17.4 times (95% CI 3.3 to 32.2) greater risk of surgery for ET and a 32.2 times (95% CI 15.8 to 35.6) greater risk for nil stereopsis at > or = 5 years of age. CONCLUSION: Treatment protocols designed to optimize stereoacuity outcomes promote long-term stability of alignment.

Accommodation, Ocular↗

Predictive factors underlying the restoration of macular binocular vision in adults with acquired strabismus.

PURPOSE: To investigate whether macular binocular vision can be permanently lost following acquired strabismus and to identify predictive factors underlying its restoration. SUBJECTS AND METHODS: Twenty-three patients with strabismus acquired after binocular vision maturation were enrolled. Factors studied included duration of eye misalignment, age at treatment, pre-surgical strabismus type, pre-surgical diplopia, and pre-surgical capacity for binocularity. The restoration of macular binocular vision was evaluated between 1 and 3 years following successful eye re-alignment and was defined as 60 seconds of arc stereopsis or better on the Titmus circles and/or the Preschool Randot Stereoacuity test. RESULTS: Sixteen of 23 (70%) or 7/23 (30%) of patients achieved macular binocular vision following successful surgical eye realignment using the Titmus circles versus the Preschool Randot Stereoacuity test. Patients with < or =12 months constant eye misalignment were more likely to achieve macular binocular vision following treatment than patients with >12 months constant eye misalignment. CONCLUSIONS: Macular binocular vision continues to be susceptible to permanent loss in adult patients. Factors that are predictive of the restoration of macular binocular vision include duration of constant eye misalignment and the pre-surgical capacity for binocularity.

Adolescent↗

Nasal myectomy of the inferior oblique muscles for recurrent elevation in adduction.

PURPOSE: Recurrence of inferior oblique overaction (IOOA) after recession or anterior transposition of the inferior oblique (IO) muscles is a common problem. We have been treating such cases by nasal myectomy of the IO, where a segment of approximately 5 mm is removed from the nasal portion, leaving the temporal portion of the IO with its insertion and its ancillary origin, the neurofibrovascular junction, intact. Here we report long-term findings on this procedure. METHODS: Records were analyzed on 72 eyes belonging to 40 patients with recurrent IOOA of grade +1 or more, who received nasal myectomy of the inferior oblique (NMIO) in one (8 cases) or both (32 cases) eyes, and who had a minimum of 3 months follow-up. RESULTS: At follow-up (range 3.6 months to 12 years; median 26 months), 27 patients (68%) showed no IO overaction, whereas 11 (28%) showed improvement of at least one grade point and 2 (5%) showed no improvement. Of the patients with residual IO overaction, three received additional surgery: in two of these patients IO overaction was subsequently eliminated while no additional follow-up was available for the third patient. The effects of NMIO on dissociated vertical deviation were variable. CONCLUSION: In 95% of these patients nasal myectomy of the IO resulted in reduction and in many cases elimination of IO overaction. An advantage of this procedure is that the temporal portion of the muscle, with its ancillary origin and insertion, is preserved.

Adolescent↗

A randomized trial of atropine regimens for treatment of moderate amblyopia in children.

OBJECTIVE: To compare daily atropine to weekend atropine as prescribed treatments for moderate amblyopia in children younger than 7 years. DESIGN: Prospective, randomized multicenter clinical trial (30 sites). PARTICIPANTS: One hundred sixty-eight children younger than 7 years with amblyopia in the range of 20/40 to 20/80 associated with strabismus, anisometropia, or both. INTERVENTION: Randomization either to daily atropine or to weekend atropine for 4 months. Partial responders were continued on the randomized treatment until no further improvement was noted. MAIN OUTCOME MEASURE: Visual acuity (VA) in the amblyopic eye after 4 months. RESULTS: The improvement in VA of the amblyopic eye from baseline to 4 months averaged 2.3 lines in each group. The VA of the amblyopic eye at study completion was either (1) at least 20/25 or (2) better than or equal to that of the sound eye in 39 children (47%) in the daily group and 45 children (53%) in the weekend group. The VA of the sound eye at the end of follow-up was reduced by 2 lines in one patient in each group. Stereoacuity outcomes were similar in the 2 groups. CONCLUSIONS: Weekend atropine provides an improvement in VA of a magnitude similar to that of the improvement provided by daily atropine in treating moderate amblyopia in children 3 to 7 years old. This article contains additional online-only material available at http://www.ophsource.com/periodicals/ophtha.

Amblyopia↗