Clinical Course of Consecutive Esotropia after Surgery to Correct Recurrent Intermittent Exotropia

PURPOSE: To analyze the clinical aspects of consecutive esotropia after intermittent exotropia reoperation and study the prognosis and associated risk factors. METHODS: The present study included 34 patients with intermittent exotropia who underwent reoperation; incidence rate, risk factors, treatment methods and prognosis of the postoperative consecutive esotropia were analyzed. RESULTS: Of the 34 patients, 12 developed consecutive esotropia that persisted longer than a month after the reoperation; a higher incidence rate was observed in patients with esodeviation greater than 16 prism diopter (PD) on postoperative day 1 and in patients who received unilateral lateral muscle recession and medial muscle resection during the operation (p < 0.05). Conversely, factors such as age, deviation angle, refractive power, anisometropia, lateral incomitance and oblique muscle dysfunction prior to the reoperation did not affect the incidence of consecutive esotropia. The patients who developed consecutive esotropia received conservative treatments such as alternative occlusion therapy and fresnel prism wearing; 10 of 12 patients showed significant clinical improvements. CONCLUSIONS: Consecutive esotropia frequently occurs after intermittent exotropia reoperation if the patient had esodeviation greater than 16 PD on postoperative day 1 or received unilateral lateral muscle recession and medial muscle resection. The conservative treatments of the consecutive esotropia showed good clinical response and improved prognosis.

The Effect of Unilateral Medial Rectus Resection for Recurrent Intermittent Exotropia

PURPOSE: The purpose of this study is to investigate the effect of unilateral medial rectus muscle resection (UMR) for the treatment of recurrent intermittent exotropia after bilateral lateral rectus muscle recession (BLR). METHODS: Medical records of 121 subjects who underwent UMR for the treatment of recurrent intermittent exotropia after BLR with more than six months of follow-up were reviewed. Patients were classified into two groups, the 4-mm group who underwent 4-mm UMR and the 5-mm group who underwent 5-mm UMR. Successful postoperative motor alignment was defined as within 10 prism diopters (PD) of exotropia and four PD of esotropia. RESULTS: The mean time interval between the primary surgery and recurrence was 13.55 +/- 20.78 months (1-120 months). Average follow-up period after secondary surgery was 27.42 +/- 15.98 months (6-48 months). Cumulative success rate at six months after UMR was 87.1% in the 4-mm group and 88.2% in the 5-mm group, respectively, and that at 24 months was 72.7% in the 4-mm group and 50.0% in the 5-mm group (p = 0.132). The average effect of resection was 4.87 +/- 0.91 PD/mm in the 4-mm group and 4.73 +/- 0.84 PD/mm in the 5-mm group (p = 0.374). CONCLUSIONS: Because of recurrent intermittent exotropia, less time is required for surgery in UMR after BLR, and patients and parents are more likely to accept a secondary surgery because of single muscle surgery. Therefore, UMR may be an effective surgical method for patients with 16-30 PD of recurrent intermittent exotropia.

The Clinical Course of Recurrent Intermittent Exotropia After Previous Unilateral Recess-Resection Surgery

PURPOSE: To investigate the clinical course of recess-resection (R & R) on the contralateral eye for recurrent intermittent exotropia after previous unilateral R & R surgery. METHODS: A retrospective analysis was conducted on patients who had unilateral R & R surgery and patients who had a second R & R surgery on the contralateral eye for recurrent intermittent exotropia with at least 12 months of postoperative follow-up. RESULTS: Our study included 490 patients with unilateral R & R and 119 patients with contralateral R & R. Recurrence was defined as an ocular misalignment of greater than 11PD during follow-up. Cumulative probabilities of surgical success rates were 42.7% and 66.4%, respectively (p=0.000). CONCLUSIONS: Exotropia reappeared in recurrent intermittent exotropia after contralateral R & R. However, when considering a long-term prognosis, the cumulative probabilities of surgical success were significantly higher in the second surgery.

Unilateral Recession-Resection Versus Re-resection of Medial Rectus in Recurrent Intermittent Exotropia

PURPOSE: To compare the surgical outcomes of recession-resection (R&R) on the contralateral eye and medial rectus re-resection surgery for recurrent intermittent exotropia in patients who previously underwent unilateral recess-resection. METHODS: A retrospective analysis was performed on patients who underwent either R&R on the contralateral eye or medial rectus re-resection surgery for recurrent intermittent exotropia who had unilateral R&R previously with a minimum follow-up period of at least 12 months. RESULTS: Thirty-nine patients underwent contralateral R&R surgery and 13 patients underwent medial rectus re-resection surgery. The satisfactory surgical result was considered between -5 (prism diopters, PD) and +10PD. The success rate of the contralateral R&R group and medial rectus re-resection group was 84.6% and 100% (p=0.317) at postoperative 1 week, 79.5% and 46.2% (p=0.034) at postoperative 6 months, 69.2% and 38.5% (p=0.048) at postoperative 12 months, and 51.3% and 7.7% (p=0.006) at the last follow-up visit. CONCLUSIONS: The long-term surgical outcome of R&R surgery on the contralateral eye for the patients with recurrent intermittent exotropia who previously underwent unilateral R&R surgery was significantly better than medial rectus re-resection.

The Clinical Analysis after Reoperation for Recurrent Intermittent Exotropia

PURPOSE: To analyze the clinical course and relationships between the factors and surgical outcomes after reoperation for recurrent intermittent exotropia. METHODS: Surgical results were retrospectively investigated in 38 patients who had undergone reoperation at least 3 months after surgical correction. Recurrence was defined as an exodeviation of more than 10 prism diopters at the primary position. We investigated the recurrence rate according to the follow-up duration with survival analysis, and analyzed the relationships between the factors and surgical outcome. RESULTS: The mean survival period was 22.7+/-20.2 months (range, 3 to 72 months). As the follow-up duration increased, the recurrence rate progressively increased. The hazard ratio for recurrence of a unilateral medial rectus resection as a reoperation was significantly higher than that for a unilateral lateral rectus recession and medial rectus resection (recession and resection)(p=0.021). After using unilateral recession and resection as the primary surgery, the hazard ratio for recurrence of unilateral recession and resection as a reoperation was not significantly different from that for unilateral lateral rectus recession (p=0.480). After a bilateral lateral rectus recession, the hazard ratio for recurrence of unilateral medial rectus resection was not significantly different from that for bilateral medial rectus resection (p=0.076). CONCLUSIONS: The surgical options for recurrent intermittent exotropia are contralateral recession and resection or contralateral lateral rectus recession. The procedure chosen depends on the operator's preference after performing unilateral recession and resection as the primary surgery. After a bilateral lateral rectus recession, the hazard ratio for recurrence of unilateral medial rectus resection was not significantly higher than that for a bilateral medial rectus resection, but even so, a bilateral medial rectus resection may be more effective than unilateral medial rectus resection for recurrent intermittent exotropia.