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𝘚𝘵𝘢𝘳𝘨𝘢𝘳𝘥𝘵’𝘴 𝘋𝘪𝘴𝘦𝘢𝘴𝘦 𝘐𝘯𝘷𝘦𝘴𝘵𝘪𝘨𝘢𝘵𝘪𝘰𝘯𝘴 𝘢𝘯𝘥 𝘔𝘢𝘯𝘢𝘨𝘦𝘮𝘦𝘯𝘵 ⁣

𝙁𝙡𝙪𝙤𝙧𝙚𝙨𝙘𝙚𝙞𝙣 𝘼𝙣𝙜𝙞𝙤𝙜𝙧𝙖𝙥𝙝𝙮:⁣

● Dark choroid sign- Not exclusive to Stargardt disease.⁣

● Due to a lack of early choroidal hyperfluorescence, which is⁣

blocked by high-grade lipofuscin accumulation in the RPE, thus improving visualization of the small retinal capillaries that become easily evident over the dark, non-fluorescent and high-contrast choroid (blockhead arrow)⁣

● Atrophic fovea- choroidal vessels become visible⁣

● Fundus flecks are seen as small irregular hyperfluorescent lesions⁣

(arrow). The clinically visible flecks do not necessarily correspond to the window-defects in the FFA.⁣




𝙁𝙪𝙣𝙙𝙪𝙨 𝘼𝙪𝙩𝙤𝙛𝙡𝙪𝙤𝙧𝙚𝙨𝙘𝙚𝙣𝙘𝙚:⁣

● Abnormally increased FAF represents excessive lipofuscin accumulation in the RPE.⁣

● Inversely, decreased areas of FAF relate to low level RPE metabolic activity which normally underlies local atrophy with secondary photoreceptor loss.⁣

● Abnormally high FAF intensity with all other normal parameters suggests that RPE lipofuscin deposition may be the first pathophysiological event in ABCA4-related disease.⁣

𝙀𝙍𝙂 :⁣

● Normal in early disease. Reduced scotopic and photopic responses in advanced cases.⁣

● Slow dark adaptation⁣

𝙊𝘾𝙏 :⁣

● Shows atrophic changes and disorganisation in photoreceptors⁣

● RPE and lipofuscin deposits maybe detected within the parafoveal RPE.⁣




𝙈𝙖𝙣𝙖𝙜𝙚𝙢𝙚𝙣𝙩 :⁣

● No proven treatment.⁣

● Avoid Vitamin A and its supplements- makes the disease worse.⁣

● PUFA such as Docosahexaenoic acid (DHA) shown to reduce toxicity of⁣

A2E ( In autosomal dominant Stargardt)⁣

● Gene therapy⁣

● RPE precursor cells derived from embryonic stem cells injected⁣

subretinally.⁣

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𝗦𝘁𝗮𝗿𝗴𝗮𝗿𝗱𝘁’𝘀 𝗗𝗶𝘀𝗲𝗮𝘀𝗲⁣ ⁣ ● Most common macular dystrophy⁣ ● Presents within first two decades but central vision loss may not occur until later in life⁣ ● AR- Mutation in ABCA4 gene on chromosome 1p21-22⁣ ● AD Stargardt disease (STGD3) is rarer - ELOVL4 gene⁣



⁣ 𝘚𝘺𝘮𝘱𝘵𝘰𝘮𝘴:⁣ ● B/L central visual loss, photophobia, colour vision abnormalities, central scotomas, slow dark adaptation⁣ ● Visual deterioration progresses rapidly.⁣ ⁣ 𝘍𝘶𝘯𝘥𝘶𝘴: ⁣ ● Affects the macula ‘beaten metal appearance’ ● Maybe normal in early cases- can be mistaken as functional visual loss⁣ ● Late: Pigment mottling, Macular atrophy, bull’s eye⁣ maculopathy, fundus flecks⁣ ● Flecks- pisciform, round or dot-like yellow-white lesions- accumulation of lipofuscin in the RPE but may also represent areas of⁣ regional depigmentation and atrophy.⁣ ● Distribution does not correlate well with the visual loss⁣ ● May form individual or confluent patterns and have a typical central distribution with variable mid-periphery involvement⁣ ⁣ 𝘝𝘪𝘴𝘶𝘢𝘭 𝘧𝘪𝘦𝘭𝘥:⁣ ● Normal in early stages⁣ ● Later, relative Central scotomas develop progressing to absolute central scotomas.⁣ ● Peripheral visual fields preserved.⁣ ⁣ 𝘗𝘢𝘵𝘩𝘰𝘭𝘰𝘨𝘺:⁣ Histology shows build up of lipofuscin like pigment in the RPE specifically⁣ bisretinoid, N-retinylidene-N retinylethanolamine protein⁣ ⁣ 𝘍𝘶𝘯𝘥𝘶𝘴 𝘧𝘭𝘢𝘷𝘪𝘮𝘢𝘤𝘶𝘭𝘢𝘵𝘶𝘴⁣ Shares obvious phenotypic similarities with Stargardt disease and it is now consensual that fundus flavimaculatus and Stargardt disease are genetically linked and that the former represents a subset of Stargardt manifestations.⁣ Later disease onset and slower visual deterioration, making fundus flavimaculatus a milder condition⁣ Flecks are more diffusely scattered throughout the posterior pole and extend out to the midperiphery, but the macula is less involved, allowing better visual performance.⁣ ⁣ 𝘐𝘯𝘷𝘦𝘴𝘵𝘪𝘨𝘢𝘵𝘪𝘰𝘯𝘴 𝘢𝘯𝘥 𝘔𝘢𝘯𝘢𝘨𝘦𝘮𝘦𝘯𝘵 𝘪𝘯 𝘵𝘩𝘦 𝘯𝘦𝘹𝘵 𝘱𝘰𝘴𝘵!⁣

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