脑干与周围间隙的MR解剖学研究及临床意义

THE RESEARCH ON ANATOMY OF BRAINSTEM AND PERIPHERAL GAP BY MRI AND CLINICAL SIGNIFICANCE

目的：观察脑干与周围间隙的MR测量结果,求证MR实际应用意义。方法：通过对120例正常成人的MR测量研究,并与4例自然冰冻大体断面标本相对照,探讨正常脑干与周围间隙的MR影象解剖,同时观察了18例脑干肿瘤和21例橄榄-桥脑-小脑萎缩（OPCA）的MR表现。结果：120例正常国人的脑MR正中矢状位成像中,清晰显示导水管的有106例（88.3%）;脑MR正中矢状位成像所显示的脑干及周围结构与解剖标本近乎一致;测量了正常国人的脑干与周围结构的正常值范围,且不同年龄及性别间的正常值表现不同;桥脑与桥前池比值（B/F）、延髓与延髓前池比值（C/G）在判断脑干的正常形态及异常改变中意义较大,B/F正常值范围为3.32－5.28（平均4.3）,C/G正常值范围为0.72－2.68（平均1.7）;脑干肿瘤组中,脑干的绝对测量值均增大,B/F、C/G值也明显增大,OPCA组则与之相反。结论：脑MR正中矢状位成像可以清晰显示活体脑干及周围结构,正常成人脑干及周围脑室、脑池存在着正常值范围,但应用时需注意考虑年龄和性别的因素。

Objective：Measure brainstem and peripheral gap by mri and disscuss Actual Pertinent Significance.Methods：To explore the MR anatomy of normal brainstem and adjacent space through measurements of 120 normal adults contrast to 5 cases of natural frozen cadaver specimens.18 brainstem tumors and 21 olivopontocerebellar atrophy（OPCA） were studied with MRI,too.Results：The data showed that 106（88.3%） showing the aqueducts clearly in 120 MRI median sagittal planes.The normal brainstem and adjacent structures showed on MRI were almost the same with cadaver specimens.Normal brainstem and adjacent space had the normal range of the parameters respectively,but the normal range varied when related to sex distinction and ages.The ratios of pons to pontine cistern（B/F） and medulla to medullary cist ern（C/G） had important value in judging the abnorma l brainstem or not.The normal range of B/F was 3.32-5.28（average 4.3）,C/G was 0.72-2.68（average 1.7）.In brainstem tumor group,absolute parameters of every part were all increased,B/F and C/G increased too.OPCA group showed just oppositely.Conclusions：MRI mid-sagittal p lane can show the alive brainstem and ad jacent structures clearly.Brainstem and adjacent space of normal adults each had normal range of parameters.But age and sex distinction should be considered when appling to clinical diagnosis.