title: Clinical Evaluation of Four-Muscle Tenotomy Surgery for Nystagmus.
abstract: OBJECTIVE
  To document prospectively the effect of four-muscle tenotomy surgery on visual acuity (VA) and nystagmus intensity and assess, by the use of a questionnaire, the experience of adult patients and the parents of children who have had the four-muscle tenotomy procedure for nystagmus in the absence of strabismus or an anomalous head position. The qualitative perceived benefits or lack thereof from the procedure were compared to the subjective effects on nystagmus intensity and VA.
  
  
  METHODS
  Fifteen patients diagnosed as having congenital/infantile or acquired nystagmus, including albinism or other visual sensory disorders without anomalous head positions or coexisting strabismus, were included in this study. The changes in preoperative and postoperative VA and nystagmus were evaluated based on clinical and perceptual measurements and video recordings.
  
  
  RESULTS
  All 15 patients had preoperative and postoperative ophthalmological examinations. One patient had a postoperative conjunctival cyst, which was successfully removed. Fourteen patients (93%) showed clinical VA improvement in at least one eye. Fourteen patients were video recorded preoperatively and postoperatively to analyze their nystagmus intensity; case 9 was not included. Postoperatively, 10 patients (71%) showed a decrease in nystagmus intensity. Thirteen patients (87%) perceived vision improvement and 11 patients (73%) perceived a decrease in nystagmus intensity. All patients experienced either clinically improved VA or a decrease in nystagmus intensity. Fourteen patients (93%) perceived either improved VA or a decrease in nystagmus intensity. The preoperative and postoperative changes in VA (P = .002) and nystagmus intensity (P = .043) were both statistically significant.
  
  
  CONCLUSIONS
  The authors have shown that four-muscle tenotomy surgery for nystagmus can improve VA and decrease nystagmus intensity. The study yielded subjective patient satisfaction, modest objective improvement in VA, and no significant complications.
authors.forename: Michael
authors.initials: M
authors.lastname: Dubner
authors.forename: Leonard B
authors.initials: LB
authors.lastname: Nelson
authors.forename: Kammi B
authors.initials: KB
authors.lastname: Gunton
authors.forename: Judith
authors.initials: J
authors.lastname: Lavrich
authors.forename: Bruce
authors.initials: B
authors.lastname: Schnall
authors.forename: Barry N
authors.initials: BN
authors.lastname: Wasserman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D020417:Nystagmus, Congenital / Q000503:physiopathology / Q000601:surgery*; D009801:Oculomotor Muscles / Q000601:surgery*; D011183:Postoperative Complications; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D058971:Tenotomy / Q000379:methods*; D014792:Visual Acuity / Q000502:physiology