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oe1(光电查) - 科学论文

3 条数据
?? 中文(中国)
  • Quantitative Fundus Autofluorescence and Optical Coherence Tomography in <i>PRPH2/RDS</i> - and <i>ABCA4</i> -Associated Disease Exhibiting Phenotypic Overlap

    摘要: PURPOSE. To assess whether quantitative fundus autofluorescence (qAF), a measure of RPE lipofuscin, and spectral-domain optical coherence tomography (SD-OCT) can aid in the differentiation of patients with fundus features that could either be related to ABCA4 mutations or be part of the phenotypic spectrum of pattern dystrophies. METHODS. Autofluorescence images (308, 488-nm excitation) from 39 patients (67 eyes) were acquired with a confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference and were quantified as previously described. In addition, horizontal SD-OCT images through the fovea were obtained. Patients were screened for ABCA4 and PRPH2/RDS mutations. RESULTS. ABCA4 mutations were identified in 19 patients (mean age, 37 ± 12 years) and PRPH2/RDS mutations in 8 patients (mean age, 48 ± 13 years); no known ABCA4 or PRPH2/RDS mutations were found in 12 patients (mean age, 48 ± 9 years). Differentiation of the groups using phenotypic SD-OCT and AF features (e.g., peripapillary sparing, foveal sparing) was not reliable. However, patients with ABCA4 mutations could be discriminated reasonably well from other patients when qAF values were corrected for age and race. In general, ABCA4 patients had higher qAF values than PRPH2/RDS patients, while most patients without mutations in PRPH2/RDS or ABCA4 had qAF levels within the normal range. CONCLUSIONS. The high qAF levels of ABCA4-positive patients are a hallmark of ABCA4-related disease. The reason for high qAF among many PRPH2/RDS-positive patients is not known; higher RPE lipofuscin accumulation may be a primary or secondary effect of the PRPH2/RDS mutation.

    关键词: scanning laser ophthalmoscope,PRPH2/RDS,optical coherence tomography,quantitative fundus autofluorescence,retinal pigment epithelium,lipofuscin,recessive Stargardt disease,ABCA4,pattern dystrophy

    更新于2025-09-11 14:15:04

  • Flecks in Recessive Stargardt Disease: Short-Wavelength Autofluorescence, Near-Infrared Autofluorescence, and Optical Coherence Tomography

    摘要: PURPOSE. We evaluated the incongruous observation whereby ?ecks in recessive Stargardt disease (STGD1) can exhibit increased short-wavelength auto?uorescence (SW-AF) that originates from retinal pigment epithelium (RPE) lipofuscin, while near-infrared AF (NIR-AF), emitted primarily from RPE melanin, is usually reduced or absent at ?eck positions. METHODS. Flecks in SW- and NIR-AF images and spectral-domain optical coherence tomography (SD-OCT) scans were studied in 19 STGD1 patients carrying disease-causing ABCA4 mutations. Fleck spatial distribution and progression were recorded in serial AF images. RESULTS. Flecks observed in SW-AF images typically colocalized with darkened foci in NIR-AF images; the NIR-AF pro?les were larger. The decreased NIR-AF signal from ?ecks preceded apparent changes in SW-AF. Spatiotemporal changes in ?eck distribution usually progressed centrifugally, but in one case centripetal expansion was observed. Flecks in SW-AF images corresponded to hyperre?ective deposits that progressively traversed photoreceptor-attributable bands in SD-OCT images. Outer nuclear layer (ONL) thickness negatively correlated with expansion of ?ecks from outer to inner retina. CONCLUSIONS. In the healthy retina, RPE lipofuscin ?uorophores form in photoreceptor cells but are transferred to RPE; thus the SW-AF signal from photoreceptor cells is negligible. In STGD1, NIR-AF imaging reveals that ?ecks are predominantly hypo?uorescent and larger and that NIR-AF darkening occurs prior to heightened SW-AF signal. These observations indicate that RPE cells associated with ?ecks in STGD1 are considerably changed or lost. Spectral-domain OCT ?ndings are indicative of ongoing photoreceptor cell degeneration. The bright SW-AF signal of ?ecks likely originates from augmented lipofuscin formation in degenerating photoreceptor cells impaired by the failure of RPE.

    关键词: lipofuscin,fundus auto?uorescence,recessive Stargardt disease,optical coherence tomography,retinal pigment epithelium,ABCA4,scanning laser ophthalmoscope

    更新于2025-09-09 09:28:46

  • Quantitative Fundus Autofluorescence and Optical Coherence Tomography in <i>ABCA4</i> Carriers

    摘要: PURPOSE. To assess whether carriers of ABCA4 mutations have increased RPE lipofuscin levels based on quantitative fundus auto?uorescence (qAF) and whether spectral-domain optical coherence tomography (SD-OCT) reveals structural abnormalities in this cohort. METHODS. Seventy-?ve individuals who are heterozygous for ABCA4 mutations (mean age, 47.3 years; range, 9–82 years) were recruited as family members of affected patients from 46 unrelated families. For comparison, 57 affected family members with biallelic ABCA4 mutations (mean age, 23.4 years; range, 6–67 years) and two noncarrier siblings were also enrolled. Auto?uorescence images (308, 488-nm excitation) were acquired with a confocal scanning laser ophthalmoscope equipped with an internal ?uorescent reference. The gray levels (GLs) of each image were calibrated to the reference, zero GL, magni?cation, and normative optical media density to yield qAF. Horizontal SD-OCT scans through the fovea were obtained and the thicknesses of the outer retinal layers were measured. RESULTS. In 60 of 65 carriers of ABCA4 mutations (age range, 9–60), qAF levels were within normal limits (95% con?dence level) observed for healthy noncarrier subjects, while qAF levels of affected family members were signi?cantly increased. Perifoveal ?eck-like abnormalities were observed in fundus AF images in four carriers, and corresponding changes were detected in the outer retinal layers in SD-OCT scans. Thicknesses of the outer retinal layers were within the normal range. CONCLUSIONS. With few exceptions, individuals heterozygous for ABCA4 mutations and between the ages of 9 and 60 years do not present with elevated qAF. In a small number of carriers, perifoveal ?eck-like changes were visible.

    关键词: heterozygous carrier,retinal pigment epithelium,lipofuscin,recessive Stargardt disease,optical coherence tomography,quantitative fundus auto?uorescence,Abca4,scanning laser ophthalmoscope

    更新于2025-09-04 15:30:14