永存三叉动脉的磁共振血管成像诊断(附24例分析)

Diagnosis of Persistent Primitive Trigeminal Artery on 3D TOF MRA:An Analysis of 24 Cases

目的:以大宗病例运用磁共振血管成像(MRA)检测颅内动脉,以期评估其对永存三叉动脉(PPTA)的诊断价值,并对Saltzman分型法进行补充。方法:自2007年6月至2008年9月,于我院行头颅MRA检查者4650人(男性1977人,女性2673人)。采用3D-TOF成像法,容积显示图像重建法。根据MRA显示PPTA及原始图像上血管走行,按Saltzman标准分型分为Ⅰ、Ⅱ、Ⅲ型,并根据PPTA止于小脑上动脉、小脑前下动脉、小脑后下动脉,吻合于大脑后动脉,分支状无吻合将Ⅲ型分为a、b、c、d、e五个亚型。结果:检出PPTA24例,患病率为0.52%。SaltzmanⅠ型16.67%,SaltzmanⅡ型16.67%,SaltzmanⅢ型66.66%(Ⅲa0%,Ⅲb18.75%、Ⅲc0%、Ⅲd6.25%、Ⅲe75%)。结论:磁共振血管成像可明确诊断PPTA,亦可根据动脉结构与形态间接评估其血流动力学特征。

Purpose： This study is to evaluate the value of 3D TOF MRA with VR at 3T in diagnosis and classification of persistent primitive trigeminal artery（PPTA） . Methods： MRA was performed in 4650 patients in our hospital from Jun, 2007 to Sep, 2008. The PPTAs were classified by Saltzman criteria as follow： Type Ⅰ ： The PPTA maintains the main supply to the distal basilar artery （BA）, posterior cerebral artery （PCA） and superior cerebellar artery（SCA） territories. The BA proximal to the PPTA insertion may be dysplasia and the posterior communicating artery（PcomA） may be absent; Type Ⅱ ： The PPTA maintains the main supply to SCA territories, and the PCAs receive their blood supply predominantly through patent PcomAs. The BA proximal to the PPTA insertion is normal; Type Ⅲ ： Others, using sub- type a, b, c, d, e to represent the PPTA ending in SCA, anterior inferior cerebellar artery （AICA）, posterior inferior cerebellar artery （PICA）, PCA and PPTA residual respectively. Results ： Twenty - four PPTA cases were discovered in 4650 patients. The prevalence of PPTA is 0.52%. Type I in these cases were 16.67%, type Ⅱ 66.66%, type re（0% Ⅲ a,18.75% Ⅲ b,0% Ⅲ c,6.25% Ⅲ d,75% me）. Conclusion： PPTA can be diagnosed and classified correctly according to the course of PPTA indirectly by 3D- TOF MRA with VR at 3T.