Evaluation of the macular choroidal thickness using spectral optical coherence tomography in patients with...

To assess the choroidal thickness (CT) in patients with obstructive sleep apnoea syndrome (OSAS) and healthy controls.

Prospective, cross-sectional study

Ninety-two eyes of 92 patients with OSAS and 32 eyes of 32 aged and body mass index-matched healthy subjects were enrolled.

OSAS patients were further divided into mild, moderate and severe OSAS groups according to their apnoea hypopnea index (AHI) values. The macular CT and peripapillary retinal nerve fibre layer (RNFL) thickness measurements of the subjects were obtained using spectral domain optical coherence tomography (RTVue-100, Optovue). The CT and RNFL thickness measurements of the groups were compared, and correlations among the AHI values and these measurements were calculated.

Choroidal thickness.

There were no significant differences in subfoveal and temporal CT measurements of the groups. A pairwise comparison between the groups revealed that severe OSAS group has significantly thinner CT than mild OSAS group at 3.0 mm nasal to the fovea. Also, compared with severe OSAS group, the CT measurements at 1.5 mm and 3.0 mm nasal to the fovea were significantly thicker in control eyes (both, P < 0.05). There were weak negative correlations between the nasal CT measurements and AHI in the OSAS group (nasal 1.5 mm, P = 0.002, r = -0.358; nasal 3.0 mm, P = 0.004, r = -0.336). Compared with controls, severe OSAS group had significantly thinner nasal and superior RNFL thickness measurement.

Sleep apnoea patients had choroidal structural alterations that may have significance on the pathophysiology of the ophthalmic disorders associated with OSAS.