![]() On OCT, a stage 1 hole appears as a cystic lesion in the inner layers of the retina ( Figure 3). Since its introduction, OCT has been an extremely useful tool for diagnosing and staging macular holes. Stage 1 macular holes are difficult to diagnose by slit lamp biomicroscopic examination alone, leading to a lot of subjective variation in diagnosis. The earliest stage is an impending hole, characterized by a yellow spot (stage 1a) or a yellow ring (stage 1b) at the fovea. Classification of macular holes and OCTĮvolution of macular hole and clinical appearance of the different stages of its development has been described by Gass. ![]() OCT is now used to guide management of macular holes based on various parameters, as highlighted in the subsequent sections.Ģ. It is helpful in detecting subtle early MHs as well as staging the more obvious and larger ones. The high-resolution imaging on OCT allows cross-sectional and three-dimensional evaluation of the macula, thereby providing far greater details than what can be discerned clinically. Since its development, OCT is the gold standard in the diagnosis and management of this condition. The depth resolution of OCT is typically of the order of 0.4 thousandth of an inch.Ī macular hole is defined as a full-thickness defect of retinal tissue involving the anatomic fovea and primarily the foveola of the eye ( Figures 1a, b and 2). OCT is akin to noninvasive tissue “biopsy”-it provides in vivo cross-sectional views (tomography) of internal tissue structures similar to tissue sections under a microscope. In addition to measuring transverse dimensions, it also resolves depth. OCT is based on the imaging of reflected light. Prior to its development, clinical biomicroscopic examination using the slit lamp was the mainstay for retinal structural assessment. Optical coherence tomography (OCT) was developed by David Huang and colleagues at the Massachusetts Institute of Technology (MIT). As the technology continues to improve, OCT has become indispensable for all aspects of patient care for macular holes. Postoperatively, OCT is extremely useful for documenting serial changes in the foveal architecture and is helpful in correlating functional and anatomic outcomes. Intraoperative OCT (iOCT) can identify intraoperative changes in the macular anatomy during surgery that can influence functional outcomes. OCT is useful to prognosticate cases, thereby facilitating discussions with patients and managing visual expectations preoperatively. This information enables early diagnosis and can guide the intervention of choice when treatment is deemed necessary. The cross-sectional view produced by OCT effectively distinguishes full-thickness macular holes from mimicking conditions like lamellar holes, macular pseudoholes, and cysts, which may sometimes be difficult to differentiate clinically. The tomographic information provided by OCT, akin to an in vivo biopsy, has led to a better understanding of the pathogenesis of hole formation. ![]() OCT is crucial in assessing fellow eyes of patients with a macular hole to detect preclinical changes leading to subsequent hole formation. Optical coherence tomography (OCT) is a noninvasive, diagnostic technique for accurately identifying and quantitatively characterizing macular holes. ![]()
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