Choroidal thickness changes and choriocapillary circulation analysis in macular holes using optical coherence tomography angiography

Background: To investigate the changes of subfoveal choroidal thickness (SFCT) and choriocapillary circulation in idiopathic macular holes (IMHs), the fellow eyes, and normal subjects using optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA), and to explore the role of SFCT and choriocapillary circulation in the pathogenesis of IMH. Methods: A case series of 30 patients with unilateral IMH and 30 subjects, with age- and sex-matched, were included. Thirty eyes of 30 patients with unilateral IMH, the unaffected fellow eyes, and 30 eyes of age- and sex-matched healthy patients were studied. SFCT was measured by spectral domain enhanced depth imaging optical coherence tomography (EDI SD-OCT), while vascular density and blood flow area of choriocapillary circulation were obtained by OCTA. Results: The SECT in IMH eyes (236.09 +/- 79.25 mu m) was lower than that in the unaffected fellow eyes (249.71 +/- 86.10 mu m) (P=0.040) and healthy control eyes (283.29 +/- 64.16 mu m) (P=0.001). Also, the SFCT of the unaffected fellow eyes was lower than that of the healthy control eyes (P=0.033). The superficial blood flow area and vascular density of choriocapillary in the macular area were smaller and lower in the IMH eyes (2.84 +/- 0.35 mm(2), 20.74%+/- 8.26%) than the unaffected fellow eyes (3.19 +/- 0.23 mm(2), 35.18%+/- 5.20%) and healthy control eyes (3.26 +/- 0.24 mm2, 35.20%+/- 6.49%) (P<0.001); however, no difference was observed between the unaffected fellow eyes and healthy control eyes. Conclusions: The SFCT in IMH eyes was lower than that of unaffected fellow eyes and matched control eyes. In addition, the choriocapillary blood flow area and vascular density were smaller and lower than those of the unaffected fellow eyes and normal controls. Our findings suggested that atrophy of choriocapillary might play an important role in the formation of IMH.