Myectomy of the Extraocular Muscles Without Reattachment as a Surgical Treatment for Horizontal Nystagmus.

PURPOSE: To report the comparative clinical findings for two nystagmus procedures in two consecutive case series: the Sinskey anterior extirpation procedure (SAEP) and a modification, myectomy without reattachment (MWR). METHODS: Twenty consecutive patients underwent the SAEP and 19 underwent MWR. The SAEP is a snare-assisted unmeasured deep myectomy, whereas MWR is a measured myectomy at posterior Tenon's fascia. All patients underwent comprehensive ophthalmologic and orthoptic examination with infrared videonystagmography. Binocular best corrected visual acuity, nystagmus amplitude, alignment, and versions outcomes were measured. RESULTS: The highest percentage of patients experiencing two or more lines of improvement in distance and near acuity was in the SAEP group, who were younger than 10 years and had no ocular comorbidity (100%). Distance and near acuity improved at least one line in 71% and 86% of patients in the SAEP group and 72% and 61% in the MWR group, respectively. In both groups, patients younger than 10 years had the best acuity gains. Average nystagmus amplitude was reduced 76.3% (SAEP) and 68% (MWR). Horizontal versions were more compromised in the SAEP group and one patient experienced intraoperative orbital bleeding. Patients requiring reoperation for strabismus numbered 5 of 20 (20%) in the SAEP and 3 of 19 (16%) in the MWR groups. CONCLUSIONS: Similar to SAEP, the MWR procedure reduces nystagmus amplitudes and improves visual acuity but with less limitation of versions, risk of intraoperative bleeding, and risk of postoperative strabismus. Data suggest that early surgery (for patients younger than 10 years) can have a greater beneficial effect on postoperative visual acuity. [J Pediatr Ophthalmol Strabismus. 2016;53(3):156-166.].

Reliability and application variability of a commercially available infrared videonystagmography unit.

PURPOSE: Nystagmus is a condition of involuntary eye movement. The causes for nystagmus may be congenital, idiopathic, or acquired. Considerable debate exists on the therapeutic potential of various surgical techniques. Currently, there are neither standardized protocols nor devices to record quantitative data on patients with clinical nystagmus undergoing various procedures at multiple centers to facilitate randomized prospective clinical trials. METHODS: The authors evaluated the reliability and variability of a commercially available infrared videonystagmography unit by recording eye movement waveforms elicited from normal volunteers (n = 117, 13 patients, 9 trials) by different examiners (A, B, and C). Five movement characteristics were examined, including saccadic latency, velocity and precision, and pursuit gain and velocity. RESULTS: The overall test/retest variability was low, where the median coefficient of variation of the three testers for all five eye movement categories was less than 15%, and less than 10% of the coefficients of variation calculated were more than 20%. However, there was a significant difference in interobserver variability for all outcomes, except saccade latency. CONCLUSIONS: The between-tester analysis was found to have greater variability than the test/retest reliability analysis. Future studies at multiple sites using videonystagmography measurements should aim to have each patient repeatedly tested by the same tester. In anticipation of multicenter, randomized, prospective clinical trials of surgical procedures for nystagmus, standardized protocols for nystagmographic data collection and analysis must be validated both within and among participating centers.

Single-vision lenses: a comparison of management of high AC/A esotropia and refractive esotropia.

INTRODUCTION: Management of high AC/A includes bifocal lenses, single-vision distance lenses, and surgery. Our goal was to determine the long-term outcome of single-vision lenses (SVL) for high AC/A esotropia compared with normal AC/A ET. METHODS: This retrospective study included patients with accommodative esotropia managed with SVL and a minimum 5 years of follow-up. AC/A ratio, size and control of esotropic angle, stereopsis, refractive error, and ability to control the deviation while the prescription was being weaned were measured. A study group with high AC/A esotropia was compared with a control group with refractive esotropia and a normal AC/A ratio. RESULTS: A total of 36 patients were enrolled in this study: 22 in the study group and 14 in the control group. All patients in both groups showed improvement in at least one outcome category. One patient showed deterioration in only one category. CONCLUSION: High improvement and low deterioration rates suggest that SVL are an effective treatment for high AC/A esotropia. Because there was no bifocal comparison group we cannot determine if SVL are equally effective. The results do indicate that SVL are an acceptable form of treatment for patients with high AC/A esotropia.