腱鞘巨大細胞瘤之磁振造影影像

Magnetic Resonance Imaging of Giant Cell Tumor of Tendon Sheath

回溯分析14例經過手術病理證實之腱鞘巨大細胞瘤在磁振造影上的影像表徵。分析結果發現所有腱鞘巨大細胞瘤在T1影像上呈現低或中等訊號，在質子密度影像上呈現均勻中等訊號，而在T2影像上皆呈現低或中等訊號強度，較有特異性。其中12例病灶在注射顯影劑後均呈現均勻或不均勻之訊號增強。在4例接受梯度回波脈衝T2影像序列之腫瘤，病灶皆呈現均勻高訊號強度。在伴隨抑制脂肪之T1、T2及質子密度影像，病灶皆呈現不均勻之高強度訊號。腱鞘巨大細胞瘤與相鄰腱鞘或關節囊有密不可分之關係，且有往組織間隙延伸生長的特性。磁振造影檢查可藉著不同的脈衝序列，即以T1伴隨T2影像下的低訊號變化，以及注射顯影劑後T1影像之訊號增強，可對於病灶之位置及其侵犯程度作出較為正確之評估，可有助於術前診斷之正確性及手術前的規劃，以期降低術後腫瘤再發之機率。

We retrospectively analyzed the magnetic resonance images of 14 histologically proven giant cell tumors of the tendon sheath(GCTTS).Most of the lesions showed low or intermediate signal intensity on T1-T2 and proton density-weighted images, with homogeneous or heterogeneous enhancement in post-contrast T1-weighted studies. Homogeneous high signal intensity was noted in all of the 4 cases receiving gradient echo pulse sequence. All lesions showed high signal intensity on T1-, T2- and proton density- weighted images with fat suppression technique. All GCTTS were located near adjacent tendons or joint capsules, and had a great tendency to extend between structures. In conclusion, the finding of low or intermediate signal intensity on both T1- and T2- weighted images is highly characteristic of GCTTS and allows the differential diagnosis to be narrowed. MR imaging can clearly demonstrate the relationship between GCTTS and the involved structures and precisely reveal the location and the extent of tumors, which is important for preoperative evaluation.