Abstract：
Erdheim-Chester disease (ECD) is a rare L-group histiocytosis. Orbital involvement is found in a third of cases, but few data are available concerning the radiological features of ECD-related orbital disease (ECD-ROD). Our aim was to characterize the initial radiological phenotype and outcome of patients with ECD-ROD. Initial and follow-up orbital magnetic resonance imaging (MRI) from the patients with histologically proven ECD at a national reference center were reviewed. Pathological orbital findings were recorded for 45 (33%) of the 137 patients included, with bilateral involvement in 38/45 (84%) cases. The mean age (± standard deviation) of these patients was 60 (±11.3) years and 78% were men. Intraconal fat infiltration around the optic nerve sheath adjacent to the eye globe (52%), with intense gadolinium uptake and a fibrous component was the most frequent phenotype described. Optic nerve signal abnormalities were observed in 47% of cases. Two patients had bilateral homogeneous extraocular muscle enlargement suggestive of a myositis-like involvement of ECD-ROD. None had isolated dacryoadenitis but in 17 eyes dacryodenitis was described in association with other types of orbital lesions. Only seven patients (15%) had normal brain MRI findings. ECD-associated paranasal sinus involvement and post-pituitary involvement were detected in 56% and 53% of patients, respectively. A decrease/disappearance of the lesions was observed in 17/24 (71%) of the patients undergoing late (>12 months) followups. Interestingly, ECD-ROD only rarely (7/45; 16%) revealed the disease, with exophthalmos being the most frequently identified feature in this subgroup (3/45; 6%). Even though ECD-ROD can be clinically silent, it comprises a broad array of lesions often resulting in optic nerve signal abnormalities, the functional outcome of which remains to be established. ECD-ROD should thus be assessed initially and subsequently monitored by orbital MRI and ophthalmological follow-up.
摘要：
Erdheim-Chester病（ECD）是一种罕见的L组组织细胞增生症。在三分之一的病例中发现了轨道受累，但关于ECD相关眼眶疾病(ECD-ROD)的放射学特征的数据很少.我们的目的是表征ECD-ROD患者的初始放射学表型和预后。回顾了在国家参考中心经组织学证实为ECD的患者的初始和后续眼眶磁共振成像（MRI）。纳入的137例患者中有45例（33%）的病理性眼眶发现，在38/45（84％）病例中涉及双边。这些患者的平均年龄（±标准差）为60（±11.3）岁，男性占78％。眼球附近的视神经鞘周围的眼内脂肪浸润（52％），具有强烈的钆摄取和纤维成分是描述的最常见的表型。47％的病例观察到视神经信号异常。两名患者的双侧均匀眼外肌增大，提示ECD-ROD的肌炎样受累。没有人患有孤立的泪腺炎，但在17只眼中，泪腺炎与其他类型的眼眶病变有关。只有7名患者（15％）的脑部MRI检查结果正常。在56％和53％的患者中检测到ECD相关的鼻旁窦受累和垂体后受累，分别。在经历晚期(>12个月)随访的17/24(71%)患者中观察到病变减少/消失。有趣的是,ECD-ROD很少（7/45；16％）发现这种疾病，在这个亚组中，眼球突出是最常见的特征(3/45；6%)。即使ECD-ROD可以在临床上保持沉默，它包括广泛的病变，通常导致视神经信号异常，其功能结果仍有待确定。因此，应首先评估ECD-ROD，然后通过眼眶MRI和眼科随访进行监测。
