超急性期自发性脊髓硬膜外血肿的磁共振诊断及误诊分析

目的分析超急性期自发性脊髓硬膜外血肿(SSEH)的临床特点及磁共振(MRI)表现,降低误诊率。方法回顾性分析经手术病理证实7例超急性期SSEH的临床及MRI资料,讨论误诊原因,鉴别诊断。结果首发症状均出现典型脊背部突发胀痛,继之出现进行性下肢麻木,活动功能障碍。2例既往有高血压病,7例均无明确外伤和凝血机制障碍病史,1例手术中发现蔓状扩张动静脉血管。7例SSEH,发生于颈椎1例、胸椎2例、颈胸交界部2例、胸腰段2例,均位于硬膜外腔的侧后方或正后方,血肿呈梭形。在T1加权序列(T1WI)矢状面6例表现为等信号,1例表现为略高信号;在T2加权序列(T2WI)矢状面和轴面,7例表现为高信号或混杂高信号;血肿与脊髓间可见线条状低信号间隔。增强扫描2例血肿可见边缘斑点或环形强化。本组4例误诊的原因:平扫时血肿信号不具特征性;活动性出血所致血肿增强征象不典型。结论超急性期SSEH具有不典型MRI表现,容易误诊,但结合起病时间及血肿MRI信号进行分析,有利于对血肿的诊断和鉴别诊断。

The MR Imaging Diagnosis and Misdiagnosis Analysis of Acute Spontaneous Spinal Epidural Hematoma

ObjectiveTo evaluate MRI and clinical manifestation in patients with hyperacute spontaneous spinal epidural hematoma (SSEH) and to depress misdiagnosis rate.MethodsAll the cases were approved by surgical and pathologic diagnosis,and the clinical manifestations and MRI findings of all patients with SSEH were retrospectively analyzed.And to discuss misdiagnosed causes and differential diagnosis.ResultsThe first-episode symptoms of all the cases were typically presented with sudden severe back pain and rapid development signs of compression of the spinal cord.2 cases had hypertensive disease.Arteriovenous malformation rhexis was found in one case during operation.All cases had no clear history of injury and coagulation disorders.7 cases of SSEH were in lateral posterior or posterior epidural space.The hematomas located in the cervical (n=1),thoracic (n=2) ,cervicothoracic(n=2) ,and thoracolumbar(n=2).The hematomas were fusiform in shape.On sagittal T₁WI,the signal intensity of the SSEH was isointense to spinal cord in 6 cases and slight hiperintense in 1 case.On sagittal and axial T₂WI,7 cases were hyperintense or heterogeneous hyperintense.There were a low signal septum between spinal cord and hematoma on T₁WI and T₂WI.The wall of hematoma was enhanced in 2 cases on MRI enhancement scan.The reasons of three misdiagnosis cases were:The hematoma signal was atypical on no-enhanced MR imaging,Active bleeding resulted in atypical MR imaging findings of the hematoma .ConclusionThe atypical MRI manifestation of hyperacute SSEH were easier to be misdiagnosed.It is useful for diagnosis and differentiation of hematoma based on the analysis of the MR signal intensity and hematoma age.