No abstract

The visual evoked potential (VEP) generated by the amblyopic visual system demonstrates reduced amplitude, prolonged latency, and increased variation in response timing (phase-misalignment). This study examined VEPs before and after occlusion therapy (OT) and whether phase-misalignment can account for the amblyopic VEP deficits. VEPs were recorded to 0.5-4cycles/degree gratings in 10 amblyopic children (2-6years age) before and after OT. Phase-misalignment was measured by Fourier analysis across a limited bandwidth. Signal-to-noise ratios (SNRs) were estimated from amplitude and phase synchrony in the Fourier domain. Responses were compared to VEPs corrected for phase-misalignment (individual epochs shifted in time to correct for the misalignment). Before OT, amblyopic eyes (AE) had significantly more phase-misalignment, latency prolongation, and lower SNR relative to the fellow eye. Phase-misalignment contributed significantly to low SNR but less so to latency delay in the AE. After OT, phase-alignment improved, SNR improved and latency shortened in the AE. Raw averaged waveforms from the AE improved after OT, primarily at higher spatial frequencies. Correcting for phase-misalignment in the AE sharpened VEP peak responses primarily at low spatial frequencies, but could not account for VEP waveform improvements in the AE after OT at higher spatial frequencies. In summary, VEP abnormalities from the AE are associated with phase-misalignment and reduced SNR possibly related to desynchronization of neuronal activity. The effect of OT on VEP responses is greater than that accounted for by phase-misalignment and SNR alone.

he Intermittent Exotropia Questionnaire (IXTQ) is a patientderived, intermittent exotropia-specific instrument designed to evaluate health-related quality of life (HRQOL) in children with intermittent exotropia and their parents. 1,2 The IXTQ consists of 3 parts: the 12-item child IXTQ (completed by the child to assess the child's HRQOL), the 12-item proxy IXTQ (completed by the parent to assess the child's HRQOL), and the 17-item parent IXTQ (completed by the parent regarding his or her own HRQOL). 1 The child and proxy questionnaires each have a single subscale. The parent questionnaire contains 3 subscales: psychosocial, function, and surgery. The IXTQ is reliable and valid for assessing HRQOL in children with intermittent exotropia. [1][2][3] It is available for download free of charge at http://pedig.jaeb.org/.The IXTQ was originally developed using classical test theory. Rasch analysis may be used to modify and improve existing HRQOL instruments. [4][5][6][7][8][9] In the present study, Rasch analysis was used to refine the existing IXTQ, removing items that do not contribute meaningful information to the instrument and ensuring that response options are properly interpreted. Methods Patient CohortParents gave written informed consent, and children gave written assent when required. The protocol was approved by the institutional review boards of the Mayo Clinic, Jaeb Center for Health Research, and other local sites involved in the study. Data were collected and analyzed in accordance with the Health Insurance Portability and Accountability Act guidelines. The IXTQ was completed by 575 parents of 575 children aged 1 through 16 years with intermittent exotropia at the time of their child's clinic examination, enrolled from May 15, 2008, through July 24, 2013. The 295 children aged 5 years or older completed the age-appropriate child IXTQ. Parents and children completed the IXTQ as part of routine care in the strabismus practice of one of the authors (J.M.H., n = 110) or at the enrollment examination for 1 of 2 ongoing randomized clinical trials being conducted by the Pediatric Eye Disease Investigator Group (NCT 01032603 [n = 69] and NCT 01032330 [n = 396]). Child questionnaires were administered to children aged 5 through 7 years by study personnel. All 8-to 17-year-old child, proxy, and parent questionnaires were self-administered. Patient demographics are reported in eTable 1 in the Supplement. Statistical AnalysisBefore Rasch analysis, items with floor and ceiling effects on the child, proxy, and parent IXTQs were eliminated as described in the eMethods in the Supplement. Rasch analysis was performed on each of the 4 IXTQs using the analytic methods that we have applied previously (eMethods in the Supplement). 9 The performance and structure of the Rasch-IMPORTANCE The Intermittent Exotropia Questionnaire (IXTQ) is a patient, proxy, and parental report of quality of life specific to children with intermittent exotropia. We refine the IXTQ using Rasch analysis to improve reliability and validity.OBSERVATI...

IMPORTANCECataract is an important cause of visual impairment in children. Data from a large pediatric cataract surgery registry can provide real-world estimates of visual outcomes and the 5-year cumulative incidence of adverse events. OBJECTIVE To assess visual acuity (VA), incidence of complications and additional eye operations, and refractive error outcomes 5 years after pediatric lensectomy among children younger than 13 years. DESIGN, SETTING, AND PARTICIPANTSThis prospective cohort study used data from the Pediatric Eye Disease Investigator Group clinical research registry. From June 2012 to July 2015, 61 eye care practices in the US, Canada, and the UK enrolled children from birth to less than 13 years of age who had undergone lensectomy for any reason during the preceding 45 days. Data were collected from medical record reviews annually thereafter for 5 years until September 28, 2020. EXPOSURES Lensectomy with or without implantation of an intraocular lens (IOL).MAIN OUTCOMES AND MEASURES Best-corrected VA and refractive error were measured from 4 to 6 years after the initial lensectomy. Cox proportional hazards regression was used to assess the 5-year incidence of glaucoma or glaucoma suspect and additional eye operations. Factors were evaluated separately for unilateral and bilateral aphakia and pseudophakia.RESULTS A total of 994 children (1268 eyes) undergoing bilateral or unilateral lensectomy were included (504 [51%] male; median age, 3.6 years; range, 2 weeks to 12.9 years). Five years after the initial lensectomy, the median VA among 701 eyes with available VA data (55%) was 20/63 (range, 20/40 to 20/100) in 182 of 316 bilateral aphakic eyes (58%), 20/32 (range, 20/25 to 20/50) in 209 of 386 bilateral pseudophakic eyes (54%), 20/200 (range, 20/50 to 20/618) in 124 of 202 unilateral aphakic eyes (61%), and 20/65 (range, 20/32 to 20/230) in 186 of 364 unilateral pseudophakic eyes (51%). The 5-year cumulative incidence of glaucoma or glaucoma suspect was 46% (95% CI, 28%-59%) in participants with bilateral aphakia, 7% (95% CI, 1%-12%) in those with bilateral pseudophakia, 25% (95% CI, 15%-34%) in those with unilateral aphakia, and 17% (95% CI, 5%-28%) in those with unilateral pseudophakia. The most common additional eye surgery was clearing the visual axis, with a 5-year cumulative incidence of 13% (95% CI, 8%-17%) in participants with bilateral aphakia, 33% (95% CI, 26%-39%) in those with bilateral pseudophakia, 11% (95% CI, 6%-15%) in those with unilateral aphakia, and 34% (95% CI, 28%-39%) in those with unilateral pseudophakia. The median 5-year change in spherical equivalent refractive error was −8.38 D (IQR, −11.38 D to −2.75 D) among 89 bilateral aphakic eyes, −1.63 D (IQR, −3.13 D to −0.25 D) among 130 bilateral pseudophakic eyes, −10.75 D (IQR, −20.50 D to −4.50 D) among 43 unilateral aphakic eyes, and −1.94 D (IQR, −3.25 D to −0.69 D) among 112 unilateral pseudophakic eyes. CONCLUSIONS AND RELEVANCEIn this cohort study, development of glaucoma or glaucoma suspect was common in children 5 ye...