听神经瘤的MRI诊断(20例报告)

回顾分析了20例22个听神经瘤的MRI表现。MRI检查采用0.35T超导MT/S成像系统,常规行冠状面T_1加权及横断面T_(1-)T_2加权成像。据瘤体大小将病灶分成4组,包括限于内听道者1例,1-2cm者2例,2.1-3cm者8例,大于3cm者11例,结果表明,T_1加权像对听神经瘤的诊断价值较大,主要依据是CP角内出现与听神经根部相连的肿块或听神经明显增粗;大于2cm的听神经瘤多可发生囊变、出血及脑干、Ⅳ脑室受压。除可发现位于内听道内的微小肿瘤外,MRI在肿瘤囊变、出血、周围结构受压情况、肿瘤供血血管及肿瘤与周围粘连情况的显示上均具有一定的优越性。

MRI Diangosis of Acoustic Neuroma (20 cases report)

The MRI features of 22 Iesions in 20 patients with acoustic neuroma had been analyzed retrospectively. The examinations were performed by a 0.35T superconducting magnet MT/S system coronal Tl weighted imagines and transaxial TI.T2-weighted imagines were obtained in each cases. Thc Iesions were divided into four groups according to the tumor size: (1) intracanalicular(1 lesion); (2)1-2cm (2 Iesions); (3) 2.1-3m(8 Iesions); and (4) over 3cm (11 lesions), the results suggested that Tl-weightcd imaging was much more cfficient to thc diagnosis of acoustic ncuroma; the mass in CPA connected to the acoustic nerve or the thickened nerve root was the main diagnosted features; cyst, hemorrage and compression of pon or 4th cerebroventricular could occur in the groups which were larger than 2cm. MRI not only can find small intracanalicular tumors, but also has advantages in demonstrating the formation of cyst and hemorrage, the compression of adjacent anatomical structures and the tumor vcsseis.