ABSTRACT
Retinopathy of prematurity (ROP) is one of the important causes of visual impairment in children.The current diagnosis relies mainly on the wide-field digital retinal imaging system (RetCam) and binocular indirect ophthalmoscopy.In recent years,the applications of handheld optical coherence tomography (OCT) and optical coherence tomography (OCTA) techniques in ROP have helped to observe some characteristics in ROP,such as cystoid macular changes (CMCs),shallower foveal depression,macular epiretinal membrane and other special clinical manifestations.OCT is used for follow-up observation of ROP,tt can measure the retinal layers,choroidal thickness,macular foveal vascular density and other indicators,and can evaluate the therapeutic effect on macular,retina and choroidal development and visual acuity.OCT promotes a better understanding of ROP,and helps us to gain more information about ROP.
ABSTRACT
Objective To observe the characteristics of optical coherence tomography (OCT) angiography (OCTA) in retinal vein occlusion (RVO).Methods Prospective and observational study.Clinical examination of 81 consecutive patients (86 eyes) diagnosed with RVO were included in the study,in which the branch retinal vein occlusion in 47 eyes,central retinal vein occlusion in 39 eyes.Forty-five patients were male and 36 patients were female.Aged from 28 to 76 years old,the mean age was (55.36±10.01) years old.Comprehensive optical and imaging examination were performed,including fundus photography,fundus fluorescein angiography (FFA),spectral domain OCT,en face OCT and OCTA.The retinal blood flow imaging scan mode and the optic disc blood flow imaging scan mode were performed,the scanning region in the macular area were 3 mm × 3 mm,6 mm × 6 mm,8 mm × 8 mm respectively,around the optic disc were 3 mm × 3 mm and 4.5 mm × 4.5 mm.Each region scans 2 times.The characteristics of foveal avascular zone change,macular edema,non-perfusion and optical disc edema in OCTA and their corresponding FFA and en face OCT were observed.Results By OCTA,67 eyes (77.9％) for foveal avascular zone change,23 eyes (26.7％) for macular edema,40 eyes (46.5％) for non-perfusion,and 33 eyes (38.4％) for optical disc edema can be detected.The foveal avascular zone change can be indentified as the tranformation,destruction and even vanish of the arch in superfacial layer of retinal macular area,acompanied with the dilatation and thickening of capillary vessels,the occlusion and expanding of capillary vessels arounded the foveal avascular zone in the deep layer of macular area.Those performances were more clear than FFA.The main expression of macular edema was low signal and was not as clear as en face OCT.The tortuosity and expansion of retinal vessels,density decreasing and even occlusion or abnormal traffic branch of capillary vessels can be observed in non-perfusion.These observations were similar to FFA.However,pieces of highly signal identical with non-perfusion area can b.e detected in chroid capillary.The representation of optical disc edema was the brush-like expanding of capillary vessels aroud optical disc.Conclusions OCTA can help for observing the abnormal changing of capillary vessels in foveal avascular zone and macular edema,non-perfusion and optical disc edema.Foveal avascular zone change showed occlusion and expanding of capillary vessels around the foveal avascular zone in the deep layer of macular area.Macular edema showed the weak signal.Non-perfusion showed tortuosity and expansion of retinal vessels,density decreasing and even occlusion or abnormal traffic branch of capillary vessels.Optical disc edema showed brush-like expanding of capillary vessels around optical disc.