高分辨MRI在脑脱髓鞘性假瘤中的诊断及应用价值

Application value of high resolution MRI on diagnosis of patients with intracranial DPTs

目的探讨颅脑内脱髓鞘假瘤的临床特点及其MRI影像表现特征,进一步提高对该病的诊断和认识水平。方法对2015年6月—2017年6月河南省人民医院收治的18例经临床和病理证实的中枢神经脱髓鞘假瘤患者的临床资料、MRI影像学特征和病理进行回顾性分析。结果 18例脱髓鞘假瘤患者表现为不同程度的头晕、头痛、癫痫、视力受损、语言障碍或肢体异常。MRI病变表现为累及白质的局灶性类肿块样占位性病变,7例呈均匀T_1低信号、T_2高信号,9例呈混杂T_1低信号、混杂T_2高信号,2例呈等或T_1稍高、T_2高信号,弥散受限16例,2例弥散无异常改变。15例行高分辨增强扫描病灶均有不同程度强化,其中11例为开环状、近同心圆强化,3例呈结节样强化,1例为斑片状强化;3例无强化;侧脑室病变有直角脱髓鞘征。13例激素冲击治疗后患者临床症状好转,复查MRI显示病变范围明显缩小,2例出院未治疗,后复查MRI病变进展,3例误诊为胶质瘤,术后病理证实为脱髓鞘假瘤。结论脑内脱髓鞘假瘤的MRI表现有一定的特征性,临床遇到不典型占位性病变时应考虑到脱髓鞘假瘤的可能性,对疑似病例可经临床激素试验治疗后动态观察,提高检出率、减轻或避免手术或放疗对患者的不可逆损伤。

Objective To investigate the clinical symptoms and MRI imaging features of the intracranial DPTs in order to improve the diagnosis level. Methods The MRI findings,clinical and pathological features of 18 cases clinically and pathology confirmed with DPTs were retrospectively analyzed. Results Dizziness,headache,epilepsy,limb abnormalities in different degrees were displayed in all 18 cases. MR imaging demonstrated localized tumor-like space occupying lesions involving white matter. The lesions showed homogenous low signal on T1WI and high signal on T2WI in 7 cases,inhomogenous low signal on T1WI and high signal on T2WI in 9 cases,and iso-density signal or slightly high signal on T1WI and high signal on T2WI in 2 cases. On DWI,the lesion showed high signal in 16 cases suggested the diffusion were limited,the other 2 cases were normal. Of the 15 cases with Gd-DTPA administration,vary degree enhancement was seen in each case. There was semi-ring or concentric-circle enhancement in 11 cases,nodular enhancement in 3 cases,patchy enhancement in 1 cases after enhanced scanning. No enhancement was showed in 3 cases. The right angle demyelination sign was find in the lateral ventricle lesions. Follow-up MRI imaging showed the mass lesions obviously reduced and partial remission after steroid therapy was demonstrated in 13 cases. 2 cases without treatment,Follow-up MR imaging showed the disease progress. 3 cases were misdiagnosed as glioma,but confirmed with DPTs after surgery pathology. Conclusion Intracranial DPTs has characteristic features on MRI. We should consider the DPTs When we found the atypical space-occupying lesions in clinical. Steroid therapy and follow-up MRI scanning can be used in suspected cases to improve the detection rate and reduce or avoid irrecersible damage after the surgery or radiotherapy.