超低场强MRI对颅内环状强化转移瘤的诊断与鉴别

Diagnosis and identification of intracranial ring-enhanced metastatic tumor by MRI with ultra-low field

目的总结探讨颅内环状强化转移瘤在超低场强MRI增强扫描的特点。方法对2004年8月至2006年5月经临床及手术病理证实的19例颅内环状强化病灶的增强MRI特点进行回顾性分析。结果19例患者颅内病灶共有60个。其中转移瘤15例,共52个病灶。环状强化39个,均匀结节状强化13例,伴有软脑膜强化2例。1例脑脓肿患者,3个病灶均呈环状强化。1例脑囊虫病患者,3个病灶呈环状强化并壁内偏心头节强化。2例胶质瘤患者,1例Ⅱ级星形细胞瘤轻微环状强化,1例Ⅲ级间变性胶质瘤呈花瓣状环形强化。结论颅内环状强化转移瘤MRI表现的特殊形态为诊断提供重要信息。同时结合病史、年龄和部位,在大多数情况下是可以做出正确诊断的。

Objective To summarize and discuss the characters of intracranial ring-enhanced metastatic tumors enhancedly scanned by MRI with ultra-low field. Methods Retrospective study was made of enhanced MRI characters of intracranial ring-enhanced loci in 19 cases diagnosed by clinics and operative pathology. Results Of all 19 cases there were altogether 60 loci,including 15 cases of metastatic tumor with 52 loci,among which there were 39 ring-enhancement,13 even nodular enhancement accompanied by 2 soft mater emhancement, 1 cerebral abscess case with ring-enhancement in all 3 loci, 1 case cysticercosis of brain with 3 ring enhanced loci accompanied by intraparietal cephalomere enhaucement. In 2 cases of ostrocytoma,mild ring-enhancement could be seen in 1 case of Ⅱ astrocytic tumors,petaling ring enhancement in 1 case of Ⅲ anaplastlc astrocytoma. Conclusions The specific shape showed by MRI provides important information for diagnosing intracranlal rlng-enhanced metastatic tumors. Correct diagnosis can be made in most cases with medical history ,age of patient and location of focus.