Graded Anderson procedure for correcting abnormal head posture in infantile nystagmus

Purpose: To describe the long-term results of Anderson procedure, which includes recession of the two extraocular yoke muscles responsible for eccentric eye position and abnormal head posture (AHP) in patients with infantile nystagmus. Methods: Retrospective data collection of patients who underwent an Anderson procedure at a single medical center by one surgeon from 2008 to 2016. The main outcome measure was the elimination of AHP following surgery. Results: Twenty-seven patients (18 males, 9 females) underwent an Anderson procedure during the study period. The average age at surgery was 8.6 ± 7.7 years and mean follow-up was 3.5 ± 2.4 years (range, 6 months–9 years). Before surgery all patients had AHP (17 left and 10 right head turns) greater than 25° (mean 40.1 ± 6.7°) that decreased significantly following surgery (mean 7.2 ± 7.6°, P < 0.001). Surgery resulted in complete elimination of AHP in 14 (52%) patients. In 10 (37%) patients the residual head turn was 15° or lower, and in only 3 (8%) the post-operative AHP was 25° or larger, requiring further surgery. It is important to note that none of the patients developed strabismus or duction limitation following surgery. Conclusions: Long-term results following the Anderson procedure show a stable decrease in AHP in patients with infantile nystagmus, often resulting in complete restoration of normal head posture. Involved risks of strabismus and limitation of ocular motility appear to be low.