BACKGROUND Diurnal variations in foveal thickness have been reported in several ocular pathologies including X-linked retinoschisis (XLRS), but its underlying mechanism is poorly understood. Rods are active under scotopic conditions with high metabolic demand, and its decrease may have positive effect on metabolic activity and macular thickness. The purpose of this study is to evaluate whether exposure to light and diurnal variation influence macular thickness in XLRS patients. METHODS Five patients with clinical suspicion of XLRS underwent RS1 gene sequencing and optical coherence tomography measurements at three consecutive times: morning following sleep in a dark room, morning following sleep in an illuminated room, and late afternoon following sleep in an illuminated room. Central macular thickness (CMT) was compared between measurements, and molecular analysis was performed. RESULTS Five RS1 mutations were identified: p.Gly140Arg, p.Arg141Cys, p.Gly109Glu, p.Pro193Leu, and p.Arg200His in patients 1-5, respectively. Two patients (4-5) had atrophied macula and were excluded from macular thickness variation analysis. A significant decrease in CMT between morning and afternoon measurements was observed in all patients (1-3: mean: 455.0 ± 32 μm to 342.17 ± 39 μm, 25%). Morning measurements following sleep in an illuminated room show a CMT reduction in all eyes of all patients with a mean reduction of 113 μm (mean: 547.17 ± 105 μm to 455.0 ± 32 μm, 17%). CONCLUSIONS Among XLRS patients, CMT decreased at the afternoon compared to the morning of the same day and may be reduced following sleep in an illuminated room. These results help shed light on the pathophysiologic process underlying intraretinal fluid accumulation involved with the disease.

中文翻译：

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光照和昼夜变化对X连锁视网膜分裂症中黄斑厚度的影响：一个病例系列。

背景技术已经在包括X连锁视网膜分裂症（XLRS）在内的几种眼部病理中报道了凹窝厚度的昼夜变化，但是其潜在机制尚不清楚。杆在暗藏条件下具有高的代谢需求，因此很活跃，杆的减少可能对代谢活性和黄斑厚度有积极影响。这项研究的目的是评估XLRS患者的光照和昼夜变化是否会影响黄斑厚度。方法5例临床怀疑XLRS的患者连续三个时间进行RS1基因测序和光学相干断层扫描测量：在暗室中睡觉后早晨，在有照明室中睡觉后的早晨和在有照明室中睡觉后的午后。测量之间比较了中央黄斑厚度（CMT），并进行了分子分析。结果确定了1-5例患者中的五个RS1突变：p.Gly140Arg，p.Arg141Cys，p.Gly109Glu，p.Pro193Leu和p.Arg200His。2例（4-5）有黄斑萎缩，被排除在黄斑厚度变化分析之外。在所有患者中，早晨和下午之间的CMT均显着下降（1-3：平均值：455.0±32μm至342.17±39μm，25％）。在有照明的房间中睡觉后的早晨测量显示，所有患者的所有眼睛的CMT降低，平均降低113μm（平均值：547.17±105μm至455.0±32μm，17％）。结论在XLRS患者中，下午CMT与当天早晨相比有所降低，并且在有光照的房间中睡觉后可能会降低。