title: Evaluation of subjective and objective cyclodeviation following oblique muscle weakening procedures.
abstract: OBJECTIVE
  To evaluate the subjective and objective cyclodeviational changes following different weakening procedures on superior and inferior oblique muscles.
  
  
  METHODS
  Comparative case series.
  
  
  METHODS
  In a prospective institution based study, 16 cases of A pattern horizontal strabismus having superior oblique overaction were randomized to superior oblique weakening procedures: either silicon expander or translational-recession. Similarly, 20 cases of V pattern horizontal strabismus with inferior oblique overaction were randomized for inferior oblique weakening procedures: either 10 mm Fink's recession or modified Elliot and Nankin's anteropositioning. Cyclodeviation was assessed subjectively with the synoptophore and objectively using the fundus photograph before surgery and 3 months postoperatively. Change in cyclodeviation was measured by subjective and objective methods. The index of surgical effect (ISE) was defined as the net torsional change postoperatively.
  
  
  RESULTS
  The difference between the extorsional change induced by the two superior oblique procedures, silicone expander (-6 degrees ) and translational recession (-11.3 degrees), was statistically significant (P=0.001). Translational recession caused more extorsional change (ISE=296%) than silicone expander surgery (ISE=107%). The two inferior oblique weakening procedures, Fink's recession (+2.5 degrees) and modified Elliot and Nankin's anteropositioning (+4.7 degrees) produced equitable amount of intorsional shift with no statistical difference (P=0.93). Objective measurements were significantly more than the subjective measurements.
  
  
  CONCLUSIONS
  Different weakening procedures on oblique muscles produce different changes in cyclodeviation, which persists even up to 3 months. Subjective cyclodeviation is less than the objective measurements indicating partial compensation by sensorial adaptations.
authors.affiliation: Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India. drpsharma57@yahoo.com
authors.forename: Pradeep
authors.initials: P
authors.lastname: Sharma
authors.forename: S
authors.initials: S
authors.lastname: Thanikachalam
authors.forename: Sachin
authors.initials: S
authors.lastname: Kedar
authors.forename: Rahul
authors.initials: R
authors.lastname: Bhola
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003290:Convergence, Ocular; D005260:Female; D006801:Humans; D008297:Male; D009801:Oculomotor Muscles / Q000601:surgery*; D013285:Strabismus / Q000503:physiopathology / Q000601:surgery*