This diagnostic image is a B-scan spectral-domain optical coherence tomography (OCT) of the macula, demonstrating the hallmark signs of exudative (neovascular) age-related macular degeneration (nAMD). The cross-sectional view shows three distinct types of fluid accumulation. First, intraretinal fluid (IRC) is visible as hyporeflective cystoid spaces within the inner retinal layers, outlined by green dashed circles. Second, subretinal fluid (SRF) is present as hyporeflective pockets between the neurosensory retina and the retinal pigment epithelium (RPE), indicated by white arrows. Third, a prominent serous pigment epithelial detachment (PED) is highlighted by a red dashed outline, showing the elevation of the hyperreflective RPE band away from the underlying Bruch's membrane due to sub-RPE fluid. The image illustrates the complex fluid distribution common in type 1 and type 2 macular neovascularization, emphasizing the structural disruption of the retinal layers and the RPE-choriocapillaris complex.

This diagnostic image is a cross-sectional Optical Coherence Tomography (OCT) scan of the human retina, demonstrating drug-induced retinopathy secondary to MEK inhibitor therapy. The scan shows significant disruption of normal macular architecture characterized by both intraretinal and subretinal fluid accumulation. Intraretinal fluid is visible as multiple, hyporeflective (dark), oval-shaped cystic spaces located within the inner retinal layers, leading to increased retinal thickness. Subretinal fluid is identified as a large, homogeneous hyporeflective area beneath the neurosensory retina, causing a serous retinal detachment from the underlying retinal pigment epithelium (RPE). The foveal contour is distorted by the elevation of the neurosensory layers. Black arrows highlight the intraretinal cystic changes, while a white arrow points to the subretinal fluid collection. This imaging is characteristic of MEK inhibitor-associated retinopathy, an important side effect in ophthalmology and oncology for medical students and clinicians to recognize.

Diagnostic optical coherence tomography (OCT) B-scans of the retina comparing fluid accumulation patterns in Central Serous Chorioretinopathy (CSCR) and Vogt-Koyanagi-Harada (VKH) disease. Panel A (CSCR) and Panel C (VKH without septa) show classic subretinal fluid (SRF) manifesting as hyporeflective spaces between the neurosensory retina and the retinal pigment epithelium (RPE), characterized by a single, continuous fluid pocket. Panel B illustrates VKH with subretinal septa, featuring thin, hyperreflective membranes (septa) that compartmentalize the subretinal space into 'supra-septa' and 'sub-septa' fluid pockets. Panel D demonstrates the segmentation of the 'entire region' for optical intensity analysis. The images highlight key morphological biomarkers in inflammatory uveitis (VKH), specifically the presence of subretinal fibrin or septa, which distinguishes it from the typically non-septated fluid seen in CSCR. The educational focus is on identifying subretinal compartmentalization and assessing the reflectivity (optical intensity) of fluid in different posterior segment pathologies.

This diagnostic composite includes a structural Optical Coherence Tomography (OCT) cross-section and an OCT Angiography (OCTA) en face scan of the retina. The structural OCT demonstrates signs of choroidal neovascularization (CNV) complicated by retinal pigment epithelium (RPE) atrophy. Key pathological features include intraretinal cystic spaces indicative of edema and subretinal fluid situated above a sub-RPE hyperreflective material. A prominent area of RPE atrophy is marked by increased foveal backscattering of the OCT signal into the deeper choroid. The accompanying OCTA image displays a distinct, round flow signal with a peripheral capillary fringe, confirming active neovascularization. These images illustrate the clinical progression of CNV where secondary atrophy may limit visual outcomes despite anti-VEGF therapy. The content is suitable for ophthalmology students and specialists studying retinal pathologies and multimodal imaging interpretation.

This diagnostic image is an Optical Coherence Tomography (OCT) cross-section of the human retina, demonstrating classic features of active choroidal neovascularization (CNV). The scan reveals a significant elevation of the neurosensory retina caused by subretinal fluid (SRF), appearing as a well-defined hyporeflective space between the photoreceptor layer and the underlying retinal pigment epithelium (RPE). Additionally, multiple hyporeflective intraretinal cystoid spaces are visible, indicating intraretinal fluid (IRF) or edema secondary to vascular leakage. There is an irregular, hyperreflective lesion at the level of the RPE-choriocapillaris complex, consistent with a neovascular membrane. These structural abnormalities disrupt the normal foveal contour and retinal lamination. The findings are characteristic of exudative maculopathy, often associated with conditions such as Presumed Ocular Histoplasmosis Syndrome (POHS) or neovascular age-related macular degeneration. This visual is an essential educational tool for identifying biomarkers of CNV activity and monitoring response to anti-VEGF therapy in ophthalmology.

Diagnostic Image: Optical Coherence Tomography (OCT) cross-sections of the right (OD) and left (OS) eyes of a 23-year-old female patient. The images demonstrate several pathological findings characteristic of complex retinal disease. Both scans show a diffused shallow serous neuroretinal detachment and thinning of the retinal nerve fiber layer. There are clear parafoveal intraretinal fluid collections (cystoid spaces) present within the macular retinal layers. Blue arrows indicate discrete, hyperreflective subretinal accumulations located between the sensory retina and the retinal pigment epithelium (RPE). Additionally, both eyes exhibit significant elongation and thickening of the photoreceptor outer segment layer. These features are clinically significant for evaluating conditions involving fluid redistribution, such as uveitis, central serous chorioretinopathy, or secondary effects of angle-closure glaucoma post-surgical intervention. The OCT provides high-resolution visualization of the retinal architecture, allowing for the differentiation between intraretinal edema and subretinal exudative material.