Factors Associated with the Prognosis after Operation in Children with Recurrent Intermittent Exotropia

BACKGROUND: To describe factors affecting the prognosis after operation for recurrent intermittent exotropia (X[T]) in children. METHODS: Clinical records of 50 patients who underwent operation for recurrent X(T) by a single surgeon were reviewed. The age at diagnosis of X(T), and first and second operations, deviation angle at distance and near, surgical method, concurrent vertical strabismus, stereoacuity, and Worth's Four Dot (W4D) examination before reoperation were analyzed, along with the postoperative deviation angle. A successful surgical outcome was defined as orthophoria, esodeviation ≤ 5 prism diopters, or exodeviation ≤ 10 prism diopters at distance. RESULTS: Among the 50 recurrent exotropes who underwent surgery and were followed up for more than 1 year postoperatively, 13 showed recurrent exotropia and 1 showed consecutive esotropia. The mean age at reoperation was 8.49 ± 2.19 years, and the mean duration of postoperative follow-up was 27.78 ± 12.02 months. Good near fusion before reoperation was a significant factor in the success of surgery (P = 0.006). Smaller postoperative deviation angle measured immediately and 2 months after surgery were related to smaller final deviation angle (P = 0.027 and P = 0.022, respectively). CONCLUSION: Peripheral suppression lowers the success rate of operation for recurrent X(T) in children. Overcorrection rather than orthotropia should be the target of immediate postoperative deviation angle. Peripheral suppression status and immediate and 2-month postoperative deviation angle may be important clues for predicting the final result of operation for recurrent X(T).

Surgical Outcomes of Modified Medial Rectus Resections in Recurrent Intermittent Exotropia

PURPOSE: To evaluate the outcomes of modified medial rectus (MR) resection using a lowered amount of MR resection for recurrent exotropia after bilateral lateral rectus (LR) recessions. METHODS: Fifty-six patients, who underwent MR resection from 2003 to 2017 for recurrent exotropia after bilateral LR recessions, were included. MR resection was performed using modified MR resection with a smaller amount of resection than the standard of 4 mm resection at 20 prism diopters (PD) of exotropia. Postoperative surgical results at 1 month, 6 months, 1 year and 2 years were classified as a success (5 PD esotropia [ET]-10 PD exotropia [XT]), overcorrection (>5 PD ET), and undercorrection (>10 PD XT). The clinical factors affecting surgical results at postoperative 6 month and 2 years were also evaluated. RESULTS: The success rate was 78.2% at postoperative 1 month and 87.5% at postoperative 6 months. The overcorrection rate was 21.8% and the undercorrection rate was 0% at postoperative 1 month. At postoperative 6 months, the overcorrection rate decreased to 0% and the undercorrection rate was 12.5%. The success rate was 85.7% at postoperative 1 year and 66.6% at postoperative 2 years. There was no clinical factor affecting the surgical outcomes except the ocular alignment at postoperative 1 month. The deviation at postoperative 1 month was more esotropic in patients with success at postoperative 6 months and 2 years than that in patients with undercorrection (p < 0.05). CONCLUSIONS: The modified MR resection showed favorable results of 87.5% at postoperative 6 months and 85.7% at 1 year. The angle of deviation at postoperative 1 month was an indicator of subsequent surgical outcomes.

Changes in Types of Recurrent Intermittent Exotropia after Surgical Correction of Basic Type Intermittent Exotropia

PURPOSE: To report the surgical outcomes and changes in types of recurrent exotropia after surgical correction of basic type intermittent exotropia. METHODS: We retrospectively analyzed the medical records of 91 patients who underwent reoperations for recurrent exotropia after primary surgical correction, and who visited our hospital for a period of at least one year after the reoperation. When distant deviation was >30 prism diopters (PD), we defined convergence insufficiency type (CI type) if the difference of the deviation angle was >10 PD and basic type exotropia if the difference was 33% of the distant deviation angle. RESULTS: The types of recurrent exotropia were similar to those of the preoperative condition in 68 patients (74.7%), and newly emergent CI type was observed in 23 patients (25.3%). With regard to the incidence of CI type, bilateral lateral rectus recession was more common than unilateral lateral rectus recession after primary surgery and medial rectus resection and unilateral lateral rectus recession, but the difference was not significant (p = 0.615). Recurrent CI type exotropia was observed 6 months after primary surgery (p 0.05). There was no significant difference in the success of reoperations between the two groups (p > 0.05). CONCLUSIONS: The types of recurrent exotropia after surgical correction of primary basic type intermittent exotropia differed from those of preoperative exotropia, which was not related to various factors before surgery. Recurrent exotropia was successfully treated by appropriately selected reoperations, regardless of the type of exotropia.

The Effect of Bilateral Medial Rectus Resection for Recurrent Intermittent Exotropia

PURPOSE: The purpose of this study was to investigate the effect of bilateral medial rectus muscle resection on the treatment of recurrent intermittent exotropia. METHODS: A retrospective chart analysis was conducted for 25 patients who underwent bilateral medial rectus resection for recurrent exotropia over 20 prism diopters (PD) between January 2009 and August 2015. The medial rectus was resected from 4.0 to 6.5 mm by 0.5 mm according to the deviation angle. The postoperative angle of deviation was checked at 1 day, 1 week, 3 months, 6 months, and 1 year postoperatively to investigate the amount of corrected deviation per resected muscle. RESULTS: The average preoperative deviation angle was 27.20 ± 5.02 PD exodeviation and the mean resection was 5.10 ± 0.79 mm of the medial rectus. The postoperative angle deviation was 10.68 ± 5.50 PD esodeviation at 1 day. The incidence of esodeviation tended to decrease over time. At 1 year, the postoperative angle deviation was 1.16 ± 7.54 PD esodeviation. The overcorrection rate was 84% at 1 day postoperatively but decreased to 24% at 1 year with a success rate of 68%. The corrected deviation angle per millimeter was 7.53 ± 1.22, 7.75 ± 2.16, 6.27 ± 1.74, 5.50 ± 1.54, and 5.56 ± 1.58 PD/mm at 1 day, 1 week, 3 months, 6 months, and 1 year after surgery, respectively. The dose effect per millimeter decreased over time. The corrected deviated angle per millimeter remained constant regardless of the amount of medial rectus muscle resection at 1 year postoperatively(p=0.939). CONCLUSIONS: Bilateral medial rectus resection for recurrent exotropia over 20 PD tended to overcorrect at first; however, after 1 year, the mean angle of deviation was 1.16 ± 7.54 PD esodeviation. Bilateral medial rectus resection is an effective surgical method for the treatment of recurrent exotropia over 20 PD.

Clinical Features of Recurrent Intermittent Exotropia after Reoperation for Intermittent Exotropia

PURPOSE: We reviewed the clinical features of intermittent exotropic patients who experienced recurrence after reoperation for intermittent exotropia, and identified the risk factors and prognoses. METHODS: The incidences, risk factors, treatment modalities, and prognoses of patients with recurrent exotropia were analyzed in 39 patients who underwent reoperation due to a relapse of exotropia after the first intermittent exotropia. RESULTS: Among 39 patients, 24 (61.5%) had recurrent intermittent exotropia and 15 patients had no recurrence with intermittent exotropia. There was no difference in the recurrence of intermittent exotropia with age, deviation, refraction, anisometropia, outward discrepancy, and the vertical deviation before the reoperation. However, when the first operation was performed with bilateral lateral rectus recession and the reoperation was performed with bilateral medial rectus resection or unilateral medial rectus resection, intermittent exotropia tended to recur more than when the first operation was performed with one eye with lateral rectus recession and medial rectus resection, followed by reoperation with the other lateral rectus recession and medial rectus resection (p 10 prism diopters (p < 0.05). CONCLUSIONS: The factors affecting recurrence after intermittent exotropia surgery involve surgical factors such as the surgical method and the postoperative overcorrection.

A Clinical Analysis of Intermittent Exotropia Patients Requiring More than Three Reoperations

PURPOSE: To evaluate the clinical analysis of intermittent exotropia patients who required more than three reoperations and to investigate the factors leading to situations that require more than three reoperations. METHODS: We retrospectively analyzed the results of 13 patients who underwent more than three reoperations for recurrence after the second operation, as well as for 29 patients who had successful results for operation at least 1 year after the second operation. We investigated the factors associated with surgical outcomes of the second operation using multiple logistic regression analysis, which included; onset of symptom, primary, secondary, tertiary, and fourth ages of surgery, stereopsis before and after surgery, distance and near deviation before and after surgery, and constancy of exotropia. RESULTS: There were more cases in which symptoms occurred before 1 year of age (p = 0.011) and which had constant exotropia (p = 0.023), with a large deviation at first operation (p = 0.003) after more than three operations compared to patients who only had two operations. There were less cases that achieved initial overcorrection after first operation (p = 0.003) and successful postoperative stereopsis after second operation (p = 0.043) in the three operations group than in the two operations group. Among these factors, the most important factor affecting reoperation and success after second operation was related to successful recovery of stereopsis using multiple regression analysis (odds ratio [OR] = 50.00, 95% confidence interval [CI] = 4.392–569.224, p = 0.002). CONCLUSIONS: In cases of intermittent exotropia occurring before 1 year of age, constant exotropia with a large deviation at first operation, and insufficient initial overcorrection after operation, it may be necessary for patients to receive more than three operations because of recurrence. Further, recovery of postoperative stereopsis after the second operation was the most important predictor for postoperative results.

Factors Associated with Improved Surgical Outcomes in Recurrent Exotropia

PURPOSE: To investigate the factors that improve the success rate in patients with recurrent exotropia. METHODS: A total of 60 patients who had undergone reoperation for recurrent exotropia and had at least 1 year of follow-up after surgery were included in this study. In total, 43 patients in the group with one-muscle surgery had undergone either unilateral medial rectus resection or unilateral lateral rectus recession, and the other 17 patients in the group with two-muscle surgery had undergone either bilateral medial rectus resection or lateral rectus muscle recession with medial rectus muscle resection of contralateral eye. The main outcome measure was final success rate, which was compared between the 2 groups. RESULTS: In this study, 41 (95.3%) of 43 patients in the group with one-muscle surgery had successful outcomes, while 2 (4.7%) had undercorrection at the final follow-up examination. On the other hand, 10 (58.8%) of 17 patients in the group with two-muscle surgery had successful outcomes, 5 (29.4%) had undercorrection, and 2 (11.8%) had overcorrection. The success rates were significantly different between the 2 groups (p = 0.001). In addition, preoperative deviation had the largest area under the receiver operator characteristic (ROC) curve for the success rate and exhibited an optimal balance of both sensitivity and specificity using a cut-off value of 25 PD. CONCLUSIONS: Final success rate was higher in the group with one-muscle surgery for the treatment of recurrent exotropia. Surgical outcomes are expected to be higher in patients with preoperative deviation of less than 25 PD.

Comparison of Postoperative Exodrift after First Unilateral and Second Contralateral Lateral Rectus Recession in Recurrent Exotropia

PURPOSE: To compare postoperative exodrift of the first unilateral lateral rectus (ULR) muscle recession with the exodrift of the second contralateral ULR muscle recession in patients with recurrent small-angle exotropia (XT). METHODS: We evaluated the results of a second ULR muscle recession in 19 patients with recurrent XT with deviation angles under 25 prism diopter (PD), following a first procedure of ULR muscle recession for small-angle XT. Recession of the lateral rectus muscle ranged from 8 to 9 mm. The postoperative motor alignment and degree of exodrift were investigated after the first ULR muscle recession and the second ULR muscle recession in the same patients. RESULTS: Observed differences in postoperative ocular alignment between the first ULR muscle recession and the second ULR muscle recession were statistically significant at follow-up periods of six months (7.84 +/- 4.43 vs. 3.89 +/- 3.47 PD), one year (9.58 +/- 4.97 vs. 5.21 +/- 4.94 PD), and at a final follow-up (21.11 +/- 2.98 vs. 7.52 +/- 4.06 PD) after surgery (p = 0.006, 0.013, and 0.000). Postoperative exodrift was statistically different between the first and second ULR muscle recessions at three to six months (2.89 +/-3.75 vs. 0.63 +/- 3.45 PD) and one year to final follow-up (11.52 +/- 5.50 vs. 2.32 +/- 3.53 PD) (p = 0.034 and 0.000). All of the first ULR muscle recession patients showed XT with deviation angles of more than 15 PD at the final follow-up. Regardless, the surgical success rate (<8 PD) after the second ULR recession was 63.16% (12 patients) among the total amount of patients with recurrent XT. CONCLUSIONS: This study shows that changes in exodrift after a second ULR muscle recession are less than changes after the first URL muscle recession among patients with recurrent XT. A second ULR muscle recession may be a useful surgery for small-angle XT patients with deviation angles of 25 PD or less after a first ULR muscle recession.

Dose-Effect Relationship of Unilateral Medial Rectus Resection for Recurrent Exotropia

PURPOSE: To investigate the dose-effect relationship of unilateral medial rectus resection for recurrent exotropia after bilateral lateral rectus recession. METHODS: This study comprised 39 patients who underwent unilateral medial rectus resection for recurrent exotropia under 25 PD and bilateral rectus recession for prior surgery of exotropia. The medial rectus was resected from 5.0 to 7.0 mm according to angle deviation at a distance. The postoperative deviated angle was checked at one week, 3 months and 6 months postoperatively to investigate the amount of corrected deviation per resected muscle. RESULTS: The average preoperative deviation was 21.33 +/- 2.96 PD. We resected mean 6.26 +/- 0.57 mm of the medial rectus muscle. The postoperative deviated angle was 0.82 +/- 3.47, 1.87 +/- 3.10 and 5.40 +/- 4.79 PD at 1 week, 3 months and 6 months after surgery, respectively. The corrected deviated angle per millimeter (mm) was 3.29 +/- 0.68, 3.17 +/- 0.58 and 2.75 +/- 0.89 PD at 1 week, 3 months and 6 months after surgery. There were no significant differences among the changes of postoperative deviation per millimeter according to the amount of medial rectus (MR) resection (p-value = 0.423, 0.382) The success rate was 89.75%, 92.31% and 87.18% at 1 week, 3 months and 6 months after surgery, respectively. The expected corrected angle according to the amount of resection remained constant and was 3.04-3.22 PD/mm at 3 months after surgery and 2.79-2.82 PD/mm at 6 months after surgery. CONCLUSIONS: The dose-effect per millimeter was decreased as time passed. There was no statistical difference among the corrected deviation angles per millimeter according to the amount of MR resection. We expect that the calculated dose-effect relationship may be a useful guideline for unilateral medial rectus resection for recurrent exotropia.

The Minimal Postoperative Follow-Up Period to Determine Secondary Surgery in Patients with Intermittent Exotropia

PURPOSE: We investigated the recommended minimum postoperative follow-up period for the determination of secondary corrective surgery for the consecutive esotropia (ET) and recurrent exotropia (XT) after the first intermittent XT surgery. METHODS: The medical records of 728 patients who underwent surgical treatment for intermittent XT between 2004 and 2009 with a minimum postoperative follow-up of 1 year were retrospectively reviewed. Each patient underwent a detailed sensory and motor examination, including measurements of near and distance stereoacuity, alternating-cover test, and extraocular muscle function testing. Consecutive ET was defined as esodeviation over 15 prism diopter (PD) at distance persisting for more than 6 months after surgery despite medical treatment. Recurrent XT was defined as exodeviation over 15 PD at distance after surgery despite medical treatment. RESULTS: The mean age of the 728 patients at first surgery was 7.5 years (range, 22 months - 30 years). When only the motor outcome was considered, 663 patients (91.1%) had an orthrotropia at the final follow-up and 44 patients (6.0%) among consecutive ET patients and 21 patients (2.9%) who had a recurrent XT underwent secondary surgical correction. Binocularity decreased postoperatively in patients with consecutive ET (p < 0.001), whereas the other patients demonstrated improved stereopsis postoperatively (p = 0.041, 0.021). Patients with consecutive ET showed esodeviation over 10 PD when compared with orthotropia after 2 months postoperatively (p = 0.005). At 6 months postoperatively, 17 (81.0%) of 21 patients with recurrent XT showed orthotropia with an exodeviation over 11 PD after 18 months postoperatively. CONCLUSIONS: The success rate of surgical correction for intermittent XT showed a favorable outcome. However, careful concern for consecutive ET and recurrent XT are required in postoperative follow-up periods. Over-corrected or consecutive ETs need early surgical correction because no further improvement of ocular alignment will occur after 2 months postoperatively and delayed correction can result in poor sensory binocularity. Under-corrected or recurrent XT should be observed for an extended period because of the exotropic drift after surgery, thus requiring periodic long term follow-up for secondary surgery at least for 18 months postoperatively.

The Minimal Postoperative Follow-Up Period to Determine Secondary Surgery in Patients with Intermittent Exotropia

PURPOSE: We investigated the recommended minimum postoperative follow-up period for the determination of secondary corrective surgery for the consecutive esotropia (ET) and recurrent exotropia (XT) after the first intermittent XT surgery. METHODS: The medical records of 728 patients who underwent surgical treatment for intermittent XT between 2004 and 2009 with a minimum postoperative follow-up of 1 year were retrospectively reviewed. Each patient underwent a detailed sensory and motor examination, including measurements of near and distance stereoacuity, alternating-cover test, and extraocular muscle function testing. Consecutive ET was defined as esodeviation over 15 prism diopter (PD) at distance persisting for more than 6 months after surgery despite medical treatment. Recurrent XT was defined as exodeviation over 15 PD at distance after surgery despite medical treatment. RESULTS: The mean age of the 728 patients at first surgery was 7.5 years (range, 22 months - 30 years). When only the motor outcome was considered, 663 patients (91.1%) had an orthrotropia at the final follow-up and 44 patients (6.0%) among consecutive ET patients and 21 patients (2.9%) who had a recurrent XT underwent secondary surgical correction. Binocularity decreased postoperatively in patients with consecutive ET (p < 0.001), whereas the other patients demonstrated improved stereopsis postoperatively (p = 0.041, 0.021). Patients with consecutive ET showed esodeviation over 10 PD when compared with orthotropia after 2 months postoperatively (p = 0.005). At 6 months postoperatively, 17 (81.0%) of 21 patients with recurrent XT showed orthotropia with an exodeviation over 11 PD after 18 months postoperatively. CONCLUSIONS: The success rate of surgical correction for intermittent XT showed a favorable outcome. However, careful concern for consecutive ET and recurrent XT are required in postoperative follow-up periods. Over-corrected or consecutive ETs need early surgical correction because no further improvement of ocular alignment will occur after 2 months postoperatively and delayed correction can result in poor sensory binocularity. Under-corrected or recurrent XT should be observed for an extended period because of the exotropic drift after surgery, thus requiring periodic long term follow-up for secondary surgery at least for 18 months postoperatively.

Result Comparison after Reoperation in Recurrent Exotropia According to the Type of First Operation

PURPOSE: To investigate and compare the clinical courses and surgical success rates of secondary operations in recurrent exotropia according to the type of first operation for correction of exotropia. METHODS: A retrospective chart review was performed for all patients with recurrent exotropia of the basic or pseudodivergence excess types. In group A (36 patients), bilateral lateral rectus (LR) recession was performed as the first operation and uni- or bilateral medial rectus (MR) resection was performed as the second operation. In group B (19 patients), unilateral LR recession-MR resection (R&R) was performed as the first operation and LR recession or R&R in contralateral eye as the second operation. RESULTS: There were no significant differences between the 2 groups when considering age at each operation, frequency of the amblyopia, prescription of prism, time interval for recurrence and reoperation and the final and cumulative success rates. No postoperative complications were observed in either group. The mean number of used muscles for the first and second operation was 3.9 +/- 0.4 in group A, and 3.4 +/- 0.5 in group B (p = 0.001). Mean time interval for occurrence of postoperative orthophoria was 3.7 +/- 6.2 months in group A and 6.5 +/- 16.2 in group B (p = 0.047). In group B, the incidence of esodeviation tended to increase after postoperative 1 month. CONCLUSIONS: The final success rates of reoperation between the 2 types of the first operation in recurrent exotropia were similar. Mean time between postoperative overcorrection of orthophoria was shorter in the group with bilateral LR recession followed by secondary MR resection than in the other group. Unilateral R&R followed by LR recession or R&R in contralateral eye may be more helpful to decrease the number of used muscles than in the bilateral LR recession followed by secondary MR resection.

Result Comparison after Reoperation in Recurrent Exotropia According to the Type of First Operation

PURPOSE: To investigate and compare the clinical courses and surgical success rates of secondary operations in recurrent exotropia according to the type of first operation for correction of exotropia. METHODS: A retrospective chart review was performed for all patients with recurrent exotropia of the basic or pseudodivergence excess types. In group A (36 patients), bilateral lateral rectus (LR) recession was performed as the first operation and uni- or bilateral medial rectus (MR) resection was performed as the second operation. In group B (19 patients), unilateral LR recession-MR resection (R&R) was performed as the first operation and LR recession or R&R in contralateral eye as the second operation. RESULTS: There were no significant differences between the 2 groups when considering age at each operation, frequency of the amblyopia, prescription of prism, time interval for recurrence and reoperation and the final and cumulative success rates. No postoperative complications were observed in either group. The mean number of used muscles for the first and second operation was 3.9 +/- 0.4 in group A, and 3.4 +/- 0.5 in group B (p = 0.001). Mean time interval for occurrence of postoperative orthophoria was 3.7 +/- 6.2 months in group A and 6.5 +/- 16.2 in group B (p = 0.047). In group B, the incidence of esodeviation tended to increase after postoperative 1 month. CONCLUSIONS: The final success rates of reoperation between the 2 types of the first operation in recurrent exotropia were similar. Mean time between postoperative overcorrection of orthophoria was shorter in the group with bilateral LR recession followed by secondary MR resection than in the other group. Unilateral R&R followed by LR recession or R&R in contralateral eye may be more helpful to decrease the number of used muscles than in the bilateral LR recession followed by secondary MR resection.

The Effect of Medial Rectus Resection in Reccurent Exotropia After Lateral Rectus Recession

PURPOSE: To investigate the effect of unilateral medial rectus resection in recurrent exotropia under 25 Prism Diopter after unilateral or bilateral lateral rectus recession. METHODS: A retrospective chart analysis was conducted for 21 patients who underwent unilateral medial rectus resection for recurrent exotropia under 25PD and uni- or bilateral lateral rectus recession for prior surgery of exotropia. The medial rectus was resected from 5.0 to 7.0 mm by 0.5 mm according to angle deviation at a distance. The postoperative deviated angle was checked at one week, three months and six months postoperatively to investigate the amount of corrected deviation per resected muscle. RESULTS: The average preoperative deviation was 20.57+/-3.37PD. We resected mean 6.1+/-0.62 mm of the medial rectus. At one week after the surgery, the postoperative deviated angle was 2.00+/-4.32PD, After six months it was 6.57+/-7.40PD, and there appeared to be an increase of deviation. Ten patients (48%) fused before surgery and 12 (57%) after surgery. The corrected deviation per resected muscle was 2.88+/-1.08PD. CONCLUSIONS: Unilateral medial rectus resection is an effective surgical method for the treatment of recurrent exotropia under 25 PD after lateral rectus recession.

The Comparision of Outcomes Between Lateral Rectus Muscles Re-recession and Medial Rectus Muscles Resection in Recurrent Exotropia

PURPOSE: To compare the surgical outcomes between bilateral lateral rectus muscles (BLR) re-recession and bilateral medial rectus muscles (BMR) resection in recurrent exotropia. METHODS: The medical records of patients with recurrent exotropia who underwent surgery for intermittent exotropia during the 6 years from January 2001 to December 2006 and followed up for more than 6 months were reviewed retrospectively. RESULTS: In group A, BLR recessions was performed at the first surgery and BLR re-recession was performed at the second surgery. In group B, BLR recession was performed at the first surgery and BMR resection at the second surgery. Success rates at the last follow-up after the second operation were 81.9% in Group A and 83.3% in Group B, showing no statical difference between the two groups. In group A, no significant underaction of the BLR was noted. Success rates were not statistically different between the 2 mm re-recessed subgroup and 3 mm re-recessed subgroup. CONCLUSIONS: The results support the notion that BLR re-recession successfully corrects recurrent exotropia without producing significant limitation of abduction.

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.

Comparison of Surgical Results Between Unilateral Recession-Resection and Bilateral Resections in Recurrent Exotropia

PURPOSE: The purpose of this study was to compare the surgical results between unilateral lateral rectus recession-medial rectus resection (R and R) and bilateral medial rectus resections in recurrent exotropia. METHODS: In this retrospective study, 22 patients with recurrent exotropia of the basic or pseudodivergence excess types were enrolled. In group A (14 patients), unilateral R and R was performed during the first operation, and R and R was performed in contralateral eyes during the second operation. In group B (8 patients), bilateral lateral rectus recessions were performed during the first operation and bilateral medial rectus resections during the second operation. RESULTS: The mean time interval between the first and second operations was 28.9 months (range, 5 to 64 months) in Group A and 59.9 months (range, 35 to 75 months) in Group B, which was a significant difference between the two groups (p=0.006). The success rates at last follow-up after the second operation were 85.7% in Group A and 87.5% in Group B, which was not statistically different between the two groups (p<1.000). CONCLUSIONS: There was no difference in success rate after the second operation between the two groups. Therefore, the operation method for recurrent exotropia can be chosen according to the operator's preference.

The Clinical Course of Recurrent Exotropia after Reoperation for Exodeviation

PURPOSE: To determine the clinical course of recurrent exotropia after a secondary operation for exotropia. METHODS: The surgical results in 58 patients who had undergone reoperation for recurrent exotropia (reoperation group) were retrospectively investigated and compared with those of 100 patients who had undergone primary strabismus surgery only (primary operation group) using survival analysis. RESULTS: In the reoperation group, recurrence occurred in 19 of the 58 patients (33%). Survival analysis revealed that the recurrence rates in the reoperation group were significantly lower than those in the primary operation group at the same follow-up period after the corresponding strabismus surgery (p=0.018). The distant esodeviation at the postoperative 1st week after reoperation was the only significant factor associated with the recurrence after reoperation (p=0.01). CONCLUSIONS: Exotropia did recur after a secondary operation, although the recurrence rate was lower than that after a primary operation only.

The Effect of Unilateral Lateral Rectus Recession in Recurrent Exotropia

There have been many problems in the treatment of exotropia. Especially, recurrence is very often while overcorrection is troblesome problem in the correction of recurrent exotropia. Considering less change in postoperative divergence at reoperation than at first operation, we performed unilateral lateral rectus recession in recurrent exotropia. Among the 40 patients who underwent recession and resection of horizontal recti in one eye and then unilateral lateral rectus recession in fellow eye because of recurrent exotropia greater than 15 delta, the cases who were followed more than three months were analyzed retrospectively. Forty patients were eligible. The male to female ratio was 13:27. The mean angle of recurrence was 21.4 delta regardless of the angle of first operation, and mean recurrence time was 18.8 months. The amount of divergence from postoperative 1 day to 3 or 4 month was 11.7 delta at first operation, 0.0 delta at second operation. Sixty five percents at 3 or 4 month. 60.9% at 6 or 8 month, and 55.6% at 12 or 14 month postoperatively showed stability within 10 delta. Among the 18 cases who were able to be tested fusion, 10 cases showed fusion with Worth 4-dot test(55.6%).