<h3>9歲男孩，下腰痛。</h3> <h3>增強CT橫斷位骨窗（圖A）顯示L2椎體后緣溶骨性病灶，邊界不清，局部骨皮質不連續(xù)。橫斷位T1WI(圖B)病灶呈稍高信號，椎體后緣骨皮質不聯(lián)系，病灶侵犯硬脊膜及右側椎旁間隙。STIR序列（圖C）病灶呈彌漫性高信號。增強掃描橫斷位T1WI(圖D)及矢狀位FS T1WI(圖E)示病灶明顯強化。</h3> <h3>Langerhans Cell Histiocytosis (LCH) of the Spine</h3><h3>脊柱朗格漢斯細胞組織細胞增生癥</h3><h3>背景</h3><h3>LCH comprises a rare group of disorders with a wide range of clinical presentations.</h3><h3>LCH是一組罕見的病變，臨床表現(xiàn)多種多樣。</h3><h3>It is characterized by abnormal accumulation of histiocytes in different tissues, but the etiology remains unknown</h3><h3>典型表現(xiàn)為不同組織內組織細胞的異常積聚，但病因尚不完全明確。</h3><h3>LCH is more common in children and adolescents.</h3><h3>LCH多見于兒童和青少年。</h3><h3>Bone is the most common site affected, with a predilection for the axial squeleton.</h3><h3>骨骼是LCH的好發(fā)部位之一，尤其是中軸骨更易受累。</h3><h3>臨床表現(xiàn)</h3><h3>Pain, neurologic deficits, restricted motion, deformity. Some patients may be asymptomatic.</h3><h3>主要臨床表現(xiàn)為疼痛、神經(jīng)功能缺損、運動受限、畸形等。也可有部分患者無明顯癥狀。</h3><h3>影像診斷要點</h3><h3>Solitary or multiple lytic lesions, round or oval, with poor or well defined margins in plain radiographs</h3><h3>X線平片表現(xiàn)為單發(fā)或多發(fā)溶骨性病灶，圓形或卵圓形，邊界清晰或稍不清晰。</h3><h3>CT depicts expansive lytic bone destruction that may have a geographic pattern and soft tissue masses. Limited sclerosis is seen during the healing stage.</h3><h3>CT表現(xiàn)為膨脹性溶骨性骨質破壞，呈地圖樣，可見軟組織腫塊。愈合期時可見病灶周圍硬化邊。</h3><h3>On MRI most lesions have low-to-intermediate signal intensity on T1WI, intermediate-to-high on T2WI, and they enhance avidly with contrast.</h3><h3>MRI上，病灶T1WI通常表現(xiàn)為低至中等信號，T2WI呈中等或高信號，增強掃描明顯強化。</h3><h3>Other findings include edema, paravertebral soft tissue components, and peridural compression.</h3><h3>其他表現(xiàn)包括水腫、椎旁軟組織腫塊、硬膜囊受壓。</h3><h3>Vertebra plana may be seen on all these imaging modalities.</h3><h3>所有影像學檢查均可見“扁平椎”改變。</h3><h3>鑒別診斷</h3><h3>Ewing sarcoma：More likely to have large soft tissue mass, permeative bone destruction and relative hypointense in T2</h3><h3>尤文氏肉瘤：通常軟組織腫塊較大，彌漫性骨質破壞，T2WI表現(xiàn)為相對低信號。</h3><h3>Lymphoma：Multiple levels, ivory vertebral body, hypointense-to-normal marrow</h3><h3>淋巴瘤：多椎體發(fā)病，椎體密度增高，呈“象牙椎”，MRI骨髓呈低或等信號。</h3><h3>Metastatic neuroblastoma：Multiple osteosclerotic lesions</h3><h3>轉移性神經(jīng)母細胞瘤：多發(fā)成骨性病灶。</h3><h3>Discitis-osteomyelitis：Hyperintense narrow disc with or without fluid signal</h3><h3>椎間盤炎-骨髓炎：椎間隙狹窄，呈高信號，可伴有或不伴有液性信號。</h3><h3>治療要點</h3><h3>For monostotic disease, treatment includes observation, injection of corticosteroids, nonsteroidal anti-inflammatories, and surgical curettage.</h3><h3>對于單發(fā)病灶，主要治療方法包括：隨訪觀察、注射皮質激素、非甾體類抗炎藥、手術刮除等。</h3>