Surgical technique for small-angle hypertropia
Reviewed by Fiona Rowe

In order to treat small-angle hypertropia of <5PF associated with mild / moderate upshoot in adduction, an option is to suture the inferior oblique (IO) belly to the sclera following its natural muscle direction or with anterior transposition. This study reviewed the indications for, and evaluated results of, IO muscle belly transposition with myopexy in adults with diplopia and small-angle hypertropia with IO overaction. This was a retrospective study of six patients (three female) aged 51 ±28.71 years. Five had fourth nerve palsy and one had dissociated vertical deviation (DVD). All had diplopia and four had torticollis. The primary vertical angle measured 4.17 ±1.83PD. Three had mild upshoot in adduction and this was moderate for three. Surgery was as described above for five and in one patient, was also combined with lateral rectus plication to address the horizontal angle. Diplopia resolved for five patients. One had initial good results but recurred after one month. Mean final angle was 2 ±3.1PD. Upshoot in adduction resolved for all and torticollis resolved for two and for another two improved from moderate to mild. Mean follow-up was 11.5 ±8.64 months. There were no adverse complications. Limitations of this study were its retrospective nature, small sample size and short follow-up period. The authors conclude this surgery option is a good alternative technique for small angle hypertropia.

Inferior oblique muscle belly transposition and myopexy for diplopia.
Merino-Sanz P, Chapinal A, Sanchez PGDL, Fadul FZ.
STRABISMUS
2021;29(3):144-50.