RESUMO
PURPOSE: To describe visual and vestibular functioning and the effects of age and surgery effects on postural control in healthy children with vertical strabismus. DESIGN: This is a comparative case series. METHODS: We evaluated participants at the Scientific Institute Eugenio Medea during routine clinical activities. We enrolled 30 consecutive children/adolescents (age range 4-13 years) with isolated vertical strabismus, with and without corrective surgery. Participants were split into four subgroups according to age (4-8 years versus 9-13 years) and ocular surgery (surgery versus no surgery). The clinical protocol included ophthalmological, orthoptic, neurological, physiatrical, otolaryngological, and vestibular evaluations, and the instrumental protocol included ocular cyclotorsions assessment, posturography, and vestibular myogenic-evoked potentials. Main outcome measures of the study were the prevalence of study-relevant orthopedic, ocular, vestibular, and posturographic abnormalities. RESULTS: Among the overall largely variable findings across patients' groups, we found some interesting trends: larger binocular vision and convergence disorders in younger children, smaller prevalence of asymmetric vestibular-evoked potentials in operated children, less posturographic abnormalities in younger children. No clear-cut beneficial effect of surgery was found on all clinical and instrumental parameters considered, despite good re-alignment of the eyes. CONCLUSION: The pathophysiology of postural control in vertical strabismus is extremely complex and above the potential of this study design and should be specifically addressed in deeper experimental studies.
RESUMO
PURPOSE: To study reading acuity in children and assess the reliability of its measurement using the Italian version of the MNREAD reading chart. METHODS: One hundred sixteen children from grades 3 to 8 with normal near vision were tested at a pediatric eye care institution in northeastern Italy. Visual acuity was evaluated with Early Treatment Diabetic Retinopathy Study (ETDRS) charts and reading acuity with MNREAD charts. Examination with charts 1 and 2 by the same examiner in the same visit were used as test-retest measurements. RESULTS: Mean improvement of performance from grades 3 to 8 was approximately 1 line for ETDRS acuity and 1.5 sentences for reading acuity and critical print size. Mean maximum reading speed increased from 96 to 167 words/minute. Regression analysis showed that a stable reading speed was obtained throughout sentences of decreasing size up to the critical print size. Measurement error, expressed as 95% limits of agreement, was +/- 0.136 logarithm of the minimum angle of resolution (logMAR) and +/- 0.142 logMAR for ETDRS acuity and reading acuity, respectively. Critical print size had the lowest reliability (+/- 0.193 logMAR). Maximum reading speed limits of agreement were +/- 0.077 logarithm of words per minute (logWPM), or a 19% change in words per minute. There were no detectable effects of grade and refractive error on measurement errors. CONCLUSIONS: In children, MNREAD charts provide measurements of reading acuity as reliable as ETDRS chart measurements of distance acuity on a logMAR scale. They also provide highly reliable measurements of the maximum reading speed across all grades, independent of its noticeable increase.
