Motility restriction after resection of an extraocular muscle

Bilateral Lateral Rectus Recession for the Treatment of Recurrent Exotropia after Bilateral Medial Rectus Resection

PURPOSE

To evaluate the efficacy of bilateral lateral rectus muscle recession (BLR) to treat recurrent exotropia after bilateral medial rectus muscle resection (BMR).

METHODS

Twenty-four patients who underwent BLR for recurrent exotropia and were followed up for more than 6 months were included in this retrospective study. All of them had prior BMR. The angle of deviation, success rates, near stereopsis, and surgical effect of BLR were evaluated. Surgical success was defined as postoperative deviations ≤10 prism diopters (PD).

RESULTS

The overall mean follow-up time after reoperation for patients was 24.13 ± 15.01 months (range 6-60 months). The mean angle of deviation at distance was significantly reduced from -37.75 ± 14.93 PD to +1.50 ± 6.43 PD (p < 0.001). Twenty-two (91.6%) of 24 patients had successful outcomes, 1 (4.2%) had overcorrection, and 1 (4.2%) had undercorrection at the last follow-up. Improved stereopsis after reoperation was observed in 78.3% (18/23) of the patients. The mean surgical effect was 2.78 ± 0.71 PD/mm.

CONCLUSION

Based on our results, BLR could be an effective and safe method for treating recurrent exotropia after a moderate to large amount of BMR.

Comparison of lateral rectus muscle re-recession and medial rectus muscle resection for treatment of postoperative exotropia

PURPOSE

To compare the outcomes of unilateral lateral rectus muscle re-recession and medial rectus muscle resection for treatment of recurrent or persistent exotropia.

DESIGN

Retrospective nonrandomized clinical trial.

METHODS

setting: Hospital-based clinical practice.

PATIENT POPULATION

Forty patients with recurrent or persistent exotropia following bilateral lateral rectus muscle recessions.

INTERVENTION

Fourteen patients were treated with unilateral medial rectus muscle resection and 26 with unilateral lateral rectus muscle re-recession.

MAIN OUTCOME MEASURES

Outcomes were considered successful if the patients had deviations less than 10 prism diopters (PD) at last follow-up. All patients were followed for at least 1 year postoperatively.

RESULTS

The mean preoperative deviations were 17.4 PD in the medial rectus muscle resection group and 18.1 PD in the lateral rectus muscle re-recession group. Successful outcomes were achieved in 9 of 14 patients (64%) treated with medial rectus muscle resection and 19 of 26 patients (73%) treated with lateral rectus muscle re-recession. There was no statistically significant difference between these outcomes. Mean follow-up was 4.5 years in the medial rectus muscle resection group and 2.9 years in the lateral rectus muscle re-recession group.

CONCLUSIONS

Surgery on a single muscle can be used to treat moderate-angle recurrent or persistent exotropia. Unilateral re-recession of the lateral rectus muscle and medial rectus muscle resection have equivalent success rates.

Nonsurgical management of diplopia

Diplopia is a potential undesirable outcome of nearly any ocular surgery. In some cases, the unexpected strabismus and diplopia resolve quickly without intervention, especially if due to swelling or minor insult from the surgical procedure. When double vision persists, effective treatment may be more elusive in patients in which the strabismus is the result of a restrictive process. The sudden onset of strabismus makes treatment more challenging. Frequently these patients will require surgical intervention. Where possible, patients may be managed with nonsurgical treatments until the time of surgery or indefinitely if successful and acceptable to the patient. Diplopia has been documented as a result of restrictive strabismus following vitreoretinal surgery, glaucoma surgery, orbital decompression surgery, strabismus surgery, orbital surgery, conjunctival surgery, cataract surgery, blepharoplasty, and others. The treatment of diplopia after ocular surgery is complicated by the incomitance and torsion that may be associated with restrictive strabismus as well as the variability of the deviation during healing. Nonsurgical treatment options include prisms or occlusion. Fresnel prisms are used primarily, but occasionally the prism is ground into the spectacles. Occlusion of the involved eye may be partial or complete, using a "pirate" patch, adhesive patch, Bangerter foil, tape, or related method.

The effect of unilateral medial rectus muscle resection in patients with recurrent exotropia

PURPOSE

To investigate the effect of unilateral medial rectus muscle resection for recurrent exotropia after bilateral lateral rectus muscle recession for intermittent exotropia

METHODS

A retrospective analysis was made of thirtypatients who underwent unilateral medial rectus resection for recurrent exotropia. All had prior bilateral lateral rectus recession for intermittent exotropia. Data were collected for age, the preoperative deviation, the postoperative deviation at 2 weeks, 3 months, 6 months and the last visit, and the amount of medial rectus resection performed.

RESULTS

The average preoperative deviation was 27.0+/-3.6 PD. After unilateral medial rectus resection, average deviation at distance was 2.8 PD at postoperative 2 weeks, 4.5 PD at 3 months, 5.1 PD at 6 months and 5.8 PD at last visit. The average deviation corrected per millimeter of medial rectus resection was 3.53+/-0.17 PD/mm.

CONCLUSIONS

Considering that deviation angles of recurrent exotropia is smaller than those of primary surgery and the possibility of saving the other medial rectus muscle, unilateral rectus muscle resection could be effective surgical method for recurrent exotropia.

Re-recession of the lateral rectus muscles in patients with recurrent exotropia

PURPOSE

We undertook a retrospective evaluation of changes in deviation and ocular motility after surgical rerecession of the lateral rectus (LR) muscles as a treatment for recurrent exotropia (XT).

METHODS

We describe 16 consecutive patients (age 6 to 35 years; median, 10 years; 13 children and 3 adults) with an average amount of recurrent alignment, amount of rerecession, distance from insertion to the limbus, postoperative alignment, and versions.

RESULTS

In most cases, bilateral LR muscles were rerecessed to a distance of 15 mm from the limbus, but in 5 cases with larger amount of deviation, these muscles were rerecessed to 17 mm from the limbus. A relation was found between the amount of rerecession and change in far alignment in prism diopters (r=0.46, P=0.07), but not for near deviation. The success rate (esotropia<or=10 PD or exotropia<or=8 PD) 1 to 7 days after surgery and in long-term follow-up (6-96 months; median, 25.5 months) was 100%. No significant underaction of the LR muscles was noted.

CONCLUSIONS

The results support the notion that bilateral LR rerecession to 17 mm from the limbus successfully corrects recurrent exotropia up to 33 PD and that it is particularly effective in children and adults without producing significant limitation of abduction.