Scleral Perforation as a Complication of Strabismus Surgery: A Literature Review

The aim of this review was to report the existing literature on the incidence, risk factors, treatment, and outcomes of scleral perforation as a vision-threatening complication of strabismus surgery. The current literature reported an incidence range of scleral perforation/penetration between 3 in 1,000 and 7.8%. Rectus muscle recession was the most commonly mentioned risk factor among the studies. Other risk factors were myopia, previous extraocular muscle surgery, surgeon experience, S-24 needle use, muscle reattachment posterior to the original insertion site, operating on a horizontal rectus muscle, and young age. Different views existed in the literature regarding scleral perforation management. Some ophthalmologists advocated management by cryopexy or indirect ophthalmoscopic laser uniformly, whereas others reserved it for more complicated cases. Antibiotic therapy for endophthalmitis prophylaxis was recommended by one study and shown to be practiced by some ophthalmologists. [J Pediatr Ophthalmol Strabismus. 2022;59(4):214-223.].

Extra Ocular Muscle Fenestration as a Weakening Maneuver for Surgical Management of Strabismus: A Randomized Pilot Clinical Trial

Purpose

This study aimed to evaluate the efficacy and safety of fenestration in comparison to the classic muscle recession as a weakening maneuver to horizontal and vertical extra ocular muscles in the surgical management of strabismus.

Patients and Methods

This is a pilot single blind parallel group randomized controlled trial with 1:1 allocation ratio. Male or female patients aged 1- to 60-years-old who were admitted to the Pediatric Ophthalmology and Strabismus Department for surgical correction of horizontal or vertical strabismus. Patients were randomly allocated by the envelop method to either group 1 (muscle fenestration, N=9) or group 2 (classic muscle recession, N=9). All participants were assessed at the first post operative day, at one week, and one month after the surgery for the outcomes.

Results

Postoperative ocular alignment evaluated at the first day, one week, and one month following the operation showed comparable results with no significant differences between both groups (p>0.05). The median postoperative pain score evaluated at the first day following the operation was significantly higher in fenestration group than recession group (the medians were 2.0 and 1.0, respectively, p=0.014). Alternatively, the medians of the pain score were equal in both groups at one week and one month postoperatively (p>0.999). One patient in the fenestration group developed progressive subconjunctival hemorrhage. In contrast, there was no postoperative complications in the recession group (p>0.999).

Conclusion

Efficacy and safety of muscle fenestration for correcting horizontal or vertical strabismus was comparable to the classic muscle recession.

Sympathetic ophthalmitis after scleral perforation during strabismus surgery

We report the case of a 24-year-old woman who experienced sympathetic ophthalmitis after scleral perforation during strabismus surgery. She presented postoperatively with distorted vision and was successfully treated with intravenous and oral steroids.

Vitreous hemorrhage and Rhegmatogenous retinal detachment that developed after botulinum toxin injection to the extraocular muscle: case report

Background

The authors report a case of a rare complication that occurred after botulinum toxin injection to the extraocular muscle, which was easily overlooked and successfully corrected by surgery.

Case presentation

A 34-year-old female patient visited our clinic for diplopia and ocular motility disorder after removal of an epidermoid tumor of the brain. At her initial visit, her best-corrected visual acuity (BCVA) was 20/20 for both eyes. An alternate cover test showed 45 prism-diopter esotropia and 3 prism-diopter hypertropia in the right eye. Following 6 months of observation, the deviation of the strabismus did not improve, and botulinum toxin was injected into the right medial rectus (RMR). After 6 days, she visited our clinic with decreased visual acuity of her right eye. The BCVA was found to be 20/50 for her right eye. Funduscopic examination presented a retinal tear inferonasal to the optic disc with preretinal hemorrhage. Subretinal fluid nasal to the fovea was seen on optical coherence tomography (OCT). Barrier laser photocoagulation was done around the retinal tear; however, her visual acuity continued to decrease, and vitreous hemorrhage and subretinal fluid at the lesion did not improve. In addition, a newly developed epiretinal membrane was seen on OCT. An alternate cover test presented 30 prism-diopter right esotropia. 19 weeks after RMR botulinum toxin injection, she received pars plana vitrectomy, membranectomy, endolaser barrier photocoagulation, and intravitreal bevacizumab (Avastin®) injection. After 4 months, her visual acuity improved to 20/20, and only 4 prism-diopter of right hypertropia and 3 prism-diopter of exotropia were noted. Vitreous opacity and the epiretinal membrane were completely removed, as confirmed by funduscopic and examination.

Conclusions

Sudden loss of vision after injection of botulinum toxin into the extraocular muscle may suggest a serious complication, and a prompt, thorough ophthalmic examination should be performed. If improvements are not observed, rapid surgical intervention is recommended to prevent additional complications.

Electronic supplementary material

The online version of this article (10.1186/s12886-017-0649-2) contains supplementary material, which is available to authorized users.

Strabismus-associated myopia. Review

INTRODUCTION

The treatment of strabismus associated with myopia is often a therapeutic challenge for the ophthalmologist. The strabismus associated with myopia has certain peculiarities and there are even certain types of strabismus that occur exclusively in myopia, such as strabismus fixus, requiring treatments with specific surgical techniques.

MATERIALS AND METHODS

It is important to make a correct differential diagnosis, because there are many conditions described with this association. A review is presented of strabismus associated with myopia, together with its treatment adjusted to refractive error.

RESULTS

Measurements of strabismus may be altered by the prismatic effect of the spectacles. Surgical results may be unpredictable if myopia is not taken into account. Better results were obtained with the techniques of anatomical replacement described by Yokoyama than with traditional retro-insertion-resection.

CONCLUSION

For the diagnosis and appropriate treatment of strabismus, it is important to make a correct measurement of the angle of deviation, and perform image tests prior to surgery in certain cases. The anatomical characteristics of the myopic eye should also be taken into account during surgery.

Management of Strabismus in Myopes

Strabismus in myopes can be related to anisometropia, accommodation/convergence effects, and/or muscle path deviations. This review article highlights management considerations in myopic patients.

Complications of strabismus surgery: incidence and risk factors

PURPOSE

To perform a systematic review of the complications of strabismus surgery, focusing on incidence and risk factors.

MATERIAL AND METHODS

A systematic literature search was performed using the Medline and Cochrane databases.

RESULTS

Local complications, such as conjunctival injection and mild scarring, are almost universal but only rarely have long-term clinical significance. There are several important complications that are uncommon but associated with significant long-term sequelae, including slipped muscles, lost muscles, stretched scars, incarcerated muscles, pulled-in-two syndrome, periocular infections, orbital cellulitis, scleral perforations, retinal detachments, endophthalmitis, anterior segment ischemia, and surgical errors.

DISCUSSION

Strabismus surgery is associated with a number of common and serious complications, and it is important for both surgeons and patients to be aware of the risks.

Anchored versus conventional hang-back bilateral lateral rectus muscle recession for exotropia

PURPOSE

To compare the results of conventional hang-back and anchored hang-back technique for bilateral lateral rectus muscle recessions in patients with exotropia.

METHODS

In a prospective, randomized clinical study, 60 patients underwent lateral rectus muscle recession by either conventional hang-back or anchored hang-back technique. Patients were then followed for 6 months; postoperative deviation and complications were compared. Surgery was considered successful if the postoperative deviation was within 10(Δ) of orthophoria.

RESULTS

The mean age of patients was 14.2 ± 10.3 years (median, 12 years) in the conventional hang-back group and 11.5 ± 9.3 years (median, 8 years) in anchored group (P = 0.85). The mean preoperative deviation at distance and near between the 2 groups was not statistically significant. The mean postoperative deviation was 8(Δ) ± 9(Δ) at distance and 7(Δ) ± 9(Δ) at near in the conventional group and 9(Δ) ± 8(Δ) at distance and 8(Δ) ± 8(Δ) at near in the anchored group. (P = 0.48 for distance, P = 0.98 for near). After 6 months, 63% of the conventional group and 60% of the anchored group were within 10(Δ) of orthophoria. Complications such as globe perforation, A and V patterns, and vertical deviations did not occur in either group. There were no statistically significant differences in the success rates (P = 0.79) or complications between the 2 groups.

CONCLUSIONS

The placement of additional posterior scleral sutures to "anchor" the insertion did not improve outcomes in lateral rectus muscle recession surgery.

Preferences of pediatric ophthalmologists and vitreoretinal surgeons of the treatment of scleral perforations during strabismus surgery

PURPOSE

To evaluate the preferences of pediatric ophthalmologists and vitreoretinal surgeons with regard to the initial management of scleral perforation during strabismus surgery and to determine whether they perceived one mode of treatment conferred a significant advantage over another in terms of the complication rate.

METHODS

Six hundred sixty-five pediatric ophthalmologists and 494 vitreoretinal surgeons registered with their respective national organizations were invited by an e-mail to respond to an anonymous, web-based survey. The responses to the survey were compared between groups.

RESULTS

A total of 169 ophthalmologists participated, 133 of whom were pediatric ophthalmologists and 36 vitreoretinal surgeons. Significantly more pediatric ophthalmologists than vitreoretinal surgeons recommend initially managing scleral perforation by observation (P = .001). Among pediatric ophthalmologists, method of treatment was not perceived to affect outcome (P = .75). However, laser photocoagulation was perceived to result in the best outcome among vitreoretinal surgeons (P = .03).

CONCLUSION

Significant differences exist among pediatric ophthalmologist and vitreoretinal surgeon management preferences and perceived treatment outcomes for scleral perforation.