ABSTRACT
BackgroundThe morphological examination of macular disease is very important information for the early diagnosis.Spectral domain optical coherence tomography (SD-OCT) is a gold criteria in the diagnosis of macular diseases,but its clinical application is limited in the eyes with refractive medium opacity.The resolution ratio of conventional B-scan sonography is unsatisfactory.20 MHz B-scan sonography may be a new approach to maculopathy.ObjectiveThis study was to evaluate the clinical value of 20 MHz B-scan ultrasound by comparing morphological changes of different maculopathies observed by 20 MHz ultrasound and spectral-domain OCT.MethodsA prospective study was designed.51 eyes of 51 patients with macular diseases who were determined by Tianjin Medical University Eye Center were enrolled in this study.Spectral-domain OCT was used to image the macular area,and then the 20 MHz B-scan ultrasound was used to examine the same eye to assess the value of 20 MHz B-scan ultrasound diagnosis.The macular diseases were typed according to the OCT manifestation.The characteristics of 20 MHz ultrasound for the same maculopathy were analyzed.All the patients subscribe the informed consent before the study.ResultsIn 10 eyes with macular hole determined by spectral-domain OCT,shallow dome-shaped lesion with central hollow was exhibited on the ultrasound image.The macular edema,retinal neuroepithelium layer detachment and retinoschisis were found in 16 eyes,6 eyes and 4 eyes by spectral-domain OCT,but the 20 M Hz B-Scan ultrasound presented with the focal belt-shaped elevation with non-echo zone below.In contrast,in 15 eyes of retinal pigment epithelium detachment in OCT,spectral-domain OCT showed stronger and thicker belt-shaped echo.Conclusions20 MHz B-scan ultrasound has certain value in the diagnosis and differentiation for several common maculopathies.Although it is not accurate as OCT in recognizing diseases,it could play an important role in refractive media opacity eye.
ABSTRACT
Background Retinal development continues during the early postnatal period in mammals.Correct arrangement of layers and precise location of various cells in the retina are vital for forming normal visual function during critical period plasticity.Spectral-domain optical coherence tomography(SD-OCT)provides highquality in vivo retinal imaging and the possibility to measure retinal thickness longitudinally. Objective The present study was to investigate the changes of retinal thickness during critical period plasticity in rats. Methods In vivo consecutive scanning of retinal image was performed in 10 SPF Sprague-Dawley rats at postnatal day 14(P14),P18,P21,P24 and P42 with SD-OCT,and retinal histopathological examination was used to detect retinal morphologic changes at the same postnatal ages in 20 matched rats.The whole retinal thickness,the thickness from inner limiting membrane(ILM)to inner plexiform layer(IPL),the thickness of inner nuclear layer(INL)and the thickness from outer nuclear layer(ONL)to retinal pigment epithelium(RPE)were measured using Cirrus HD-OCT system and HMIAS-2000 Imaging System in retinal sections.The measurement parameters by Cirrus HD-OCT and those by hematoxylin-eosin staining were compared.The use of animals followed the Statement of National Institute of Health (USA). Results In vivo high-resolution images of rat retinas with SD-OCT compared well with histology,which enabled quantitative comparison of the SD-OCT and histological data during critical period plasticity in rats.From P14 to P42,the retinal thickness gradually decreased with the increase of rat ages(F=15.425,P=0.000),and so were the thickness from ILM to IPL,the thickness of INL and the thickness from ONL to RPE(F=3.973,P=0.007;F=17.529,P=0.000;F=7.038,P=0.000).The retinal thickness,thickness of INL.thickness from ONL to RPE measured by Cirrus HD-OCT were significantly correlated with those measured by retinal sections among P14,P18,P21,P24 and P42 rats(r=0.794,P=0.000;r=0.784,P=0.000;r=0.681,P=0.000). Conclusion SD-OCT is a demonstratably valuable technology to study the structure of retinas in rats.The retinal thickness is shown to reduce in thickness throughout the development of the retina during critical period plasticity due to the decrease in thickness of INL and the distance from the ONL to RPE,as illustrated by OCT scanning.