上颌骨动静脉畸形的影像学特点

目的：研究上颌骨动静脉畸形（AVM）的X线、CT及MRI表现。方法对17例上颌骨AVM进行增强CT检查，其中3例行曲面断层X线检查，6例行增强MRI检查。结合血管造影（DSA）检查，分别观察病变部位、形态、边界、内部结构、邻近结构侵犯以及增强后密度／信号特征。结果病灶主要位于磨牙区（15／17），临床以上颌牙龈反复渗血或急性出血者常见，其他表现包括脸部肿胀或搏动性肿物、脸部麻木。X线上主要表现为病灶部位的密度增高。增强CT上根据颌骨的改变可大致分为2类：Ⅰ类，膨胀性及溶骨性骨质破坏（n＝12）；Ⅱ类，弥漫性骨小梁增粗，类似“磨砂玻璃”样改变（n＝5）。17例患者均有不同程度的骨质破坏及周围软组织侵犯、可见供血动脉稍增粗或增粗迂曲的回流静脉、上颌窦腔不同程度抬高；14例患侧颈外静脉（或其他回流静脉）增宽或提前显影；牙根吸收者6例。M RI上Ⅰ类主要表现为不同程度流空效应，Ⅱ类主要表现为T1 WI等低信号，T2 WI高信号，增强后明显强化。结论增强CT扫描能显示颌骨AVM病灶范围及血管侵犯情况，可为首选检查。

Imaging features of the arteriovenous malformation in maxilla

Objective To summarize the radiography ,CT and MRI findings of maxillary arteriovenous malformation (AVM ) . Methods Seventeen patients with maxillary AVM underwent panoramic radiography (3 patients) and enhanced MRI examination (6 patients) ,all the patient underwent enhanced CT examination .The clinical manifestation and imaging findings of maxillary AVM ,in‐cluding the location ,shape ,margin ,inner texture ,involvement of adjacent structures ,the density and signal intensity of the lesions , were analyzed .Results The lesions mainly located in molar areas (15/17) .The major clinical manifestation were repeated bleeding and acute bleeding .Other symptoms included swelling of the face ,pulsatile soft mass and anesthesia .The panoramic radiography only showed increased density .According to the change of the maxilla on enhanced CT images ,the lesions could be devided into two types :type Ⅰ ,showed intraosseous osteolytic destruction and cortical expansion (n=12);type Ⅱ ,showed“ground glass”appearance (n=5) .Bone destruction and soft tissue involvement ,widened feeding artery and draining veins ,elevated maxillary sinus were shown in all patients .External jugular vein enlargement and early enhancement (n=14) and root resorption (n= 6) were also detected . Flowing void on T1 and T2 weighted images (type Ⅰ) and hypo‐or isointense on T1WI ,hyperintense on T2WI and obvious enhance‐ment after injecting contrast material (type Ⅱ ) could observed .Conclusion Enhanced CT examination could be primarily recom‐mended and observe the extent of lesions and situation of vessels invaded of maxillary AVM .