Assessment of retinal and optic disc microvasculature after strabismus surgery by optical coherence tomography...

Strabismus surgery may lead to haemodynamic changes in the retina and optic nerve head which could affect eye function.

To investigate the possible haemodynamic changes of the retina and optic disc after horizontal strabismus surgery using optical coherence tomography angiography (OCTA).

37 eyes of 20 patients who underwent horizontal rectus muscle recession surgery were included to this prospective study. Demographic features, ophthalmological exam including strabismus findings were noted. OCTA examinations were performed preoperatively, postoperative first week and first month. OCTA measurements, including vessel density of the superficial and the deep capillary plexus, optic nerve head, foveal retinal thickness, peripapillary retinal nerve fibre layer thickness, were compared among the study periods.

The median age of subjects was 9 (5-45) years. Ten subjects (50%) with esotropia underwent bilateral medial rectus recession, and 10 subjects (50%) with exotropia underwent bilateral lateral rectus recession. Postoperative first week and first month superficial whole image and parafoveal capillary plexus vessel density were significantly lower than preoperative values (p = 0.010, p = 0.008, respectively). However, no significant difference was found regarding deeper capillary and optic disc vessel density, foveal retinal thickness, and retinal nerve fibre layer thickness.

Although recession surgery did not significantly influence the microcirculation of the deeper retina and optic disc in the early postoperative period, it seemed to be associated with decreased superficial vessel density which could be suggesting a possible link to hypoperfusion and ischaemia. Further studies are needed to investigate the long-term effects of bilateral symmetric recession surgery for horizontal strabismus on the microcirculation of the retina and optic nerve head.