Relativity Of Choroidal Thickness And Blood Flow In The Subfoveal Area With Idiopathic Macular Hole

Purpose To compare the choroidal thickness and the choriocapillary blood flow in the macular area in eyes with idiopathic macular hole(IMH)with that of fellow eyes and eyes of healthy controls.Also to compare the retinal thickness and blood flow in fellow eyes with eyes of healthy controls.Design Prospective Clinical Research.Methods Thirty-two patients with Idiopathic Macular Hole and 32age-and sex-matched normal control peoples were recruited.There are 32 affected eyes(Group A),according to the definition of Gass stage in 1995,4 eyes presented with stage-2 macular holes,17 eyes with stage-3 macular holes,and 11 eyes with stage-4 macular holes.32 fellow eyes(Group B)and 32 normal control eyes(Group C).Enhanced Depth Imaging OCT and OCT-Angiography were used to measure datas.The choroidal thickness and choriocapillary blood flow area were measured in the subfoveal area in three groups.The total foveal retinal thickness,ellipsoid zone thickness,foveal avascular zone,superficial blood flow density and deep blood flow density were captured in fellow eyes and normal control eyes.The values of the subfoveal choroidal thickness and choriocapillary blood flow area were compared by analysis of variance.If variance was significant,multiple comparisons were performed.The difference between the fellow eyes and normal control eyes about total foveal retinal thickness,ellipsoid zone thickness,foveal avascular zone,superficial blood flow density and deep blood flow density were tested by independent T-test or non parametric test.Upon examination,all P < 0.05,the result was statistical significance.Results Subfoveal choroidal thickness and choriocapillary blood flow area were significantly different across the 3 groups(P <0.05,analysis of variance).The mean subfoveal choroidal thickness of the affected eyes were(182.53±64.52)μm,the fellow eyes were(199.21±73.07)μm and the normal eyes were(254.21±56.85)μm,the choroid was thinner in eyes with idiopathic macular hole and fellow eyes than in control eyes significantly(P < 0.05),but there was without statistical significance in the affected eyes and the fellow eyes(P>0.05).The mean choriocapillary blood flow area of the affected eyes were(5.09±0.31)mm2,the fellow eyes were(5.41±0.20)mm2 and the normal eyes were(5.39±0.15)mm2.The choriocapillary blood flow area was reduced in eyes with idiopathic macular hole than in fellow eyes and control eyes significantly(P < 0.05),but there was without statistical significance in the fellow eyes and normal eyes(P>0.05).The foveal retina thickness of the fellow eyes was thinner than the normal eyes significantly(P < 0.05).The ellipsoid zone in the fellow eyes was thiner than the normal eyes(P = 0.001),the foveal avascular zone in the fellow eyes was expanded compared to the normal eyes significantly(P = 0.001).There were without statistical significance on superficial blood flow density and deep blood flow density in the fellow eyes and normal eyes(P>0.05).Conclusions The decrease of subfoveal choroidal thickness and choriocapillary blood flow area might more helpfully suggest a contributing role of the perfusion of the choroid in the pathogenesis of IMH.The changes of retinal thickness and the foveal avascular zone rather than superficial or deep blood flow density might be one of the risk factors for IMH which migth occur befor the formation of macuar hole.OCT-Angiography can qualify and quantify the changes of blood flow from the inner limiting membrane to the choroid layer clearly,which has ahigh clinical value.