Abstract：
Cone dystrophies and cone-rod dystrophies are a group of rare inherited pathologies characterized by degeneration of cone photoreceptors and subsequent rod involvement. The identification of causative genes is essential for diagnosis, and advanced imaging is acquiring great value in the characterization of the different phenotypic expressions.
We describe genotype-phenotype associations of an autosomal recessive ABCA4-associated cone dystrophy using multimodal imaging.
A 34-year-old woman presented with progressive visual acuity decay. Visual acuity was 20/32 for her right eye and 20/25 for her left eye. A central scotoma was detected on a 10-2 Humphrey visual field in both eyes. Funduscopy revealed perifoveal retinal pigment epithelial changes, and fundus autofluorescence using blue excitation light showed decreased autofluorescence in the central fovea of both eyes with surrounding annular ring of increased autofluorescence in the perifoveal zone; green excitation light fundus autofluorescence was more accurate in the characterization of the size, perimeter, and circularity of central hypofluorescent lesions. Optical coherence tomography revealed an incomplete focal cavitation in both foveas, and optical coherence tomography angiography images showed a reduction in the superficial and deep capillary plexus density, an increased foveal avascular area, and subtle voids in choriocapillaris blood flow. Electroretinography was consistent with cone dystrophy, and molecular testing revealed the alteration of the ABCA4 gene.
The identification of an incomplete focal cavitation could alert the clinician to consider early ABCA4 central cone dystrophy. The patient in this case also exhibited reduced vessel density in the foveal area. Both of these characteristics could be important features related to the underlying genetic mutation.
We describe genotype-phenotype associations of an autosomal recessive ABCA4-associated cone dystrophy using multimodal imaging.
A 34-year-old woman presented with progressive visual acuity decay. Visual acuity was 20/32 for her right eye and 20/25 for her left eye. A central scotoma was detected on a 10-2 Humphrey visual field in both eyes. Funduscopy revealed perifoveal retinal pigment epithelial changes, and fundus autofluorescence using blue excitation light showed decreased autofluorescence in the central fovea of both eyes with surrounding annular ring of increased autofluorescence in the perifoveal zone; green excitation light fundus autofluorescence was more accurate in the characterization of the size, perimeter, and circularity of central hypofluorescent lesions. Optical coherence tomography revealed an incomplete focal cavitation in both foveas, and optical coherence tomography angiography images showed a reduction in the superficial and deep capillary plexus density, an increased foveal avascular area, and subtle voids in choriocapillaris blood flow. Electroretinography was consistent with cone dystrophy, and molecular testing revealed the alteration of the ABCA4 gene.
The identification of an incomplete focal cavitation could alert the clinician to consider early ABCA4 central cone dystrophy. The patient in this case also exhibited reduced vessel density in the foveal area. Both of these characteristics could be important features related to the underlying genetic mutation.
摘要：
圆锥营养不良和视锥杆营养不良是一组罕见的遗传性病变，其特征是视锥光感受器退化和随后的视杆受累。致病基因的鉴定对诊断至关重要，先进的成像技术在表征不同表型表达方面具有重要价值。
我们使用多模态成像描述了常染色体隐性ABCA4相关视锥细胞营养不良的基因型-表型关联。
一位34岁的女性表现为进行性视力衰退。她的右眼视力为20/32,左眼为20/25。在两只眼睛的10-2汉弗莱视野中都检测到中央暗点。Funduscopy显示中心凹周围视网膜色素上皮改变，使用蓝色激发光的眼底自发荧光显示双眼中央凹的自发荧光减少，中央凹周围区域的自发荧光增加的环形环；绿色激发光眼底自发荧光在表征大小方面更准确，周边,和中央低荧光病变的圆形。光学相干层析成像显示两个中央凹都有不完全的局灶性空化，光学相干断层扫描血管造影图像显示浅层和深层毛细血管丛密度降低，中央凹无血管面积增加，脉络膜毛细血管血流中的细微空隙。视网膜电图与视锥细胞营养不良一致，分子检测显示ABCA4基因的改变。
不完全的局灶性空化的鉴定可以提醒临床医生考虑早期ABCA4中心锥体营养不良。在这种情况下,患者在中央凹区域中还表现出降低的血管密度。这两个特征都可能是与潜在基因突变相关的重要特征。
我们使用多模态成像描述了常染色体隐性ABCA4相关视锥细胞营养不良的基因型-表型关联。
一位34岁的女性表现为进行性视力衰退。她的右眼视力为20/32,左眼为20/25。在两只眼睛的10-2汉弗莱视野中都检测到中央暗点。Funduscopy显示中心凹周围视网膜色素上皮改变，使用蓝色激发光的眼底自发荧光显示双眼中央凹的自发荧光减少，中央凹周围区域的自发荧光增加的环形环；绿色激发光眼底自发荧光在表征大小方面更准确，周边,和中央低荧光病变的圆形。光学相干层析成像显示两个中央凹都有不完全的局灶性空化，光学相干断层扫描血管造影图像显示浅层和深层毛细血管丛密度降低，中央凹无血管面积增加，脉络膜毛细血管血流中的细微空隙。视网膜电图与视锥细胞营养不良一致，分子检测显示ABCA4基因的改变。
不完全的局灶性空化的鉴定可以提醒临床医生考虑早期ABCA4中心锥体营养不良。在这种情况下,患者在中央凹区域中还表现出降低的血管密度。这两个特征都可能是与潜在基因突变相关的重要特征。
