Postoperative Distance Stereoacuity and Prognostic Factors after Strabismus Surgery for Intermittent Exotropia Patients

• Published in: JAPANESE ORTHOPTIC JOURNAL Vol. 37; pp. 129 - 134
• Main Authors: Nakayama, Shuzo, Iwao, Keiichiro, Yamanaka, Masae, Uesaka, Tutomu, Sato, Yosimi, Seki, Yukari, Nakagawa, Takako
• Format: Journal Article
• Language: English
• Published: JAPANESE ASSOCIATION OF CERTIFIED ORTHOPTISTS 2008
• Subjects: distance stereoacuity; intermittent exotropia; prognosis; strabismus surgery
• ISSN: 0387-5172; 1883-9215
• DOI: 10.4263/jorthoptic.37.129

Purpose: To clarify the factors affecting postoperative prognosis, we measured the preoperative and postoperative distance stereoacuities of intermittent exotropia patients. Methods: Subjects were 29 patients who received the first strabismus surgery from January 1995 to December 2004. They were under a year-and-over follow-up after surgery and 6 years or older at the last visit. All patients were measured for the distance and near stereoacuity, the angle of strabismus, and the near point of convergence. The distance and near stereoacuity scores were obtained using the Nikon twin chart NC-10® and the Titmus Stereo Test, respectively. The angle of strabismus was determined using the alternating prism cover Test. All data obtained were statistically analyzed Results: All patients had excellent distance stereoacuity after surgery. The postoperative distance stereoacuity scores were significantly higher than the preoperative stereoauity scores. The postoperative distance stereoacuity scores had a positive correlation with the postoperative stereoacuity scores, while the postoperative distance stereoacuity scores had negative correlations with the preoperative distance angle of strabismus and with the postoperative near angle of strabismus. Conclusions: Strabismus surgery was useful in improving distance stereoacuity. This study also revealed that postoperative distance stereoacuity is affected by postoperative near stereoacuity, and also by preoperative distance angle of strabismus and postoperative near angle of strabismus. Our findings indicate that worsening of postoperative distance stereoacuity, which leads to poor near stereoacuity, is a valuable indicative factor for further surgery.