High-dose Anderson operation for nystagmus-related anomalous head turn

Abstract

Purpose: To evaluate the effectiveness of a high-dose Anderson procedure (AP) to correct infantile nystagmus-related anomalous head turn (HT).

Methods: Twenty-nine consecutive orthotropes with infantile nystagmus with and without associated sensory defect received high-dose AP. HT was measured while the patient tried to read letters at best-corrected visual acuity (BCVA) level at 5 m and 0.3 m. BCVA, binocular vision (BV), and alignment (prism and cover test) were measured. High-dose AP with recessions of 9-16 mm was performed. All measures were taken before and 3-6 and ≥ 8 months post surgery. Success was defined by postoperative HT ≤ 10°/HT ≤ 15°.

Results: Medians and ranges (minimum-maximum) were:. Age at surgery was 7 years (4-44). HT at 5 m and HT at 0.3 m were 35° (20-40) and 20° (0-35), respectively. After 4 months (3-6), HT was 10° (- 3-20) and 5° (- 5-20); success rates were 74%/96% and 83%/96%. After 15 months (8-45), HT was 12° (0-20) and 6° (0-15); success rates were 46%/75% and 92%/100%; residual HT > 15° occurred in 5/9 cases with recessions < 13 mm and 1/15 cases with recessions ≥ 13 mm. With recessions ≥ 13 mm, 60% (95% confidence intervals (C.I.), 33-83%) achieved HT ≤ 10° and 93% (95% C.I. 66-99%) achieved HT ≤ 15°. Overcorrection did not occur. Anomalous head posture components in vertical and frontal planes did not improve. Residual motility was 30° (10-45). The mean BCVA improved by only 0.037 logMAR (p = 0.06). BV and ocular alignment were constant, except in 2 patients whose exophoria decompensated.

Conclusions: Kestenbaum surgery is a common procedure to correct infantile nystagmus-related HT. Anderson surgery is confined to bilateral yoke muscle recession; hence, less invasive but nevertheless comparably effective, high dosage is provided.

Keywords: Anderson; Anomalous head posture; Kestenbaum; Nystagmus surgery.