Foveal Microstructure Observed by Optical Coherence Tomography (pp. 33-58)
Authors: (Takayuki Baba, Yoshinori Mitamura, Shuichi Yamamoto, Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chiba, Japan, and others)
Abstract: Recent advances of optical coherence tomography (OCT) have enabled clinicians to observe the retinal structure in greater detail and in three dimensions. Compared to conventional time domain OCT (TD-OCT), spectral domain OCT (SD-OCT) has much higher resolution and shorter data acquisition times. With the SD-OCT, a junction between inner and outer segments of photoreceptors (IS/OS junction) and the external limiting membrane (ELM) can be distinctly seen.
We have recently reported a close relationship between the restoration of IS/OS junction and the ELM and the visual acuity in eyes after surgical closure of an idiopathic macular hole (MH) and after removal of an epiretinal membrane (ERM). A better visual recovery was associated with well restored IS/OS junction and ELM in these postoperative eyes. Moreover, cases of retinitis pigmentosa (RP) with preserved IS/OS line showed significantly better visual acuity than cases with disrupted IS/OS line.
In this article, we present a review of recently published data about the relationship between microstructure of the retina in the macular region and visual function. Studies on retinal and choroidal diseases such as MH, ERM, rhegmatogenous retinal detachment, age-related macular degeneration (AMD), central serous chorioretinopathy (CSC), macular edema associated with diabetes and retinal vein occlusion, RP and other retinal dystrophy are included.
Finally, we will discuss the significance of the SD-OCT findings of foveal microstructure for better understanding of visual function.