A pair of 3-muscle surgical approaches can effectively manage large-angle esotropia in patients with chronic sixth nerve palsy, according to a study published in the British Journal of Ophthalmology. The procedures reviewed included inferior rectus belly transposition plus augmented superior rectus transposition plus medial rectus recession (ISM) and modified vertical rectus belly transposition plus medial rectus recession (VM).
Patients (N=28) with large-angle esotropia (≥50Δ) and chronic sixth nerve palsy were prospectively enrolled at a center in China. Patients underwent either ISM (n=13) or VM (n=15) performed by a single surgeon. The choice of surgical procedure was left to the surgeon. Patients received a complete ophthalmic evaluation at baseline and at 1 and 6 months. The primary outcomes were deviation in primary position, abduction limitations, and surgical complications.
The ISM and VM cohorts were 62% and 27% men, aged mean 54.9±12.0 and 45.5±11.2 years (P =.05), surgery was performed 28.3±19.1 and 20.1±22.2 months from symptom onset (P =.03), 54% and 60% had traumatic onset, 31% and 40% tumor onset, and 15% and 0% vascular onset disease, respectively.
At baseline, ISM had a lower abduction grading (mean, −6.6 vs −4.6; P <.001), higher abduction quantitation (mean, 12.8 vs 10.0 mm; P =.003), and greater horizontal deviation (mean, 81.2Δ vs 65.9Δ; P =.001) than VM.
During surgery, ipsilateral medial rectus recession was 9.6 mm in ISM and 7.8 mm in VM (P =.06).
ISM resulted in a greater change in abduction grading at the 1-month (mean improvement, −4.4 vs −2.4; P <.001) and final (mean improvement, −4.5 vs −2.4; P <.001) follow-ups. At the final follow-up no group difference in abduction grading was observed (mean, −2.2 vs −2.3; P =.91).
Similarly, ISM was associated with greater improvement to abduction quantitation at 1-month (P =.006) and the final (P =.001) follow-ups with no group differences at the final follow-up (mean, 5.2 vs 4.9 mm; P =.47).
The same trend was observed for horizontal deviation, in which the final mean horizontal deviation was 0.2Δ in the ISM and −0.3Δ in the VM groups (P =.67).
At the last visit, the success rates were 80% and 100%, vertical deviation rates were 50% and 25%, objective extorsional deviation rates were 20% and 42%, and subjective extorsional deviation rates were 10% and 17% among the ISM and VM cohorts, respectively.
Two patients who underwent ISM and 1 who underwent VM developed keratitis in the operated eye which aggravated to corneal ulceration, and patients underwent tarsorrhaphy.
The limitations of this study included the small sample size, the nonrandomized design, and the fact that abduction quantitation depended on fundus photography during surgery which was not universally obtained.
This study found that both ISM and VM surgical techniques were effective at managing large-angle esotropia with sixth nerve palsy.
Yao J, Xia W, Wang X, et al. Three-muscle surgery for large-angle esotropia in chronic sixth nerve palsy: comparison of two approaches. Br J Ophthalmol. Published online May 31, 2022. doi:10.1136/bjophthalmol-2021-320751