胃间质瘤MDCT影像特征分析

The Analysis of MDCT Imaging Features for Gastric Stromal Tumor

目的分析胃间质瘤的MDCT影像特征。方法回顾分析病理证实为胃间质瘤的CT影像资料共32例。观察内容主要包括病变部位、数目、形态、大小、生长方式及与胃壁的夹角、密度及强化模式,胃粘膜及浆膜改变,是否有淋巴结肿大与肝脏转移。结果本组32例均为单发病灶,其中胃底部19例、胃体部13例。病灶呈圆形16例,椭圆形11例,不规则形5例。病灶最大径为19-165mm。内生型14例,腔外型12例,腔内外型5例,壁内型1例。病变与邻近胃壁夹角呈锐角26例,呈钝角6例。平扫病灶呈均匀稍低或等密度19例,不均匀等低混杂密度13例,其中伴有坏死7例;三期病灶均呈均匀强化18例,不均匀明显强化14例;所有病例动脉期、门脉期、延迟期大部分或全部实性病变呈延迟强化,平均CT值分别为67HU、86HU、94HU。黏膜完整21例,黏膜中断、溃疡形成11例;所有病例浆膜完整。无1例伴胃周淋巴结肿大或肝脏转移。结论胃间质瘤MDCT影像表现有一定特征,三期增强扫描结合三维重建对其诊断具有较高价值。

Objective To analysize the imaging features of MDCT for gastric stromal tumor. Methods A retrospective analysis was performed to assess the MDCT imaging appearances of 32 cases with pathologically confirmed gastric stromal tumor. Evaluative indexes contain the lesions＇ site, number, shape, size, growth patterns and the angels between lesions and gastric wall, density and enhancement pattern, the changes of gastric mucoma and serous layer, and the encroachment of perigastric lymph nodes and liver. Results CT demonstrated single lesion in all 32 cases, of which 19 located in gastric fundus and 13 located in gastric body. Lesions were round in 16 cases, oval in 1t cases, irregular in 5 cases. The range of size was 19-165mm. The lesions included endo-luminal growth in 14 cases, extra- luminal growth in 12 cases, duplex-growth in 5 cases and intra-gastric wall in 1 case. There were acute angels between lesions and gastric wall in 26 cases, obtuse angels in 6 cases. All lesions appeared as softtissue on pre-contrast imaging with Slightly homogeneous hypo- or iso-density in 19 cases, heterogeneous density in 13 cases with necrosis in 7 cases. Homogeneous enhancement was found in 18 cases during three phases, obviously heterogeneous enhancement in 14, delayed enhancement of most or all essence were found in 32 cases during arterial, portal venous and delayed phase, average CT values were 67HU, 86HU, 94HU respectively. Complete gastric mucosa were found in 21 cases, damage or ulceration in 11 cases, the serous layer were complete in all cases. No lymph node enlargement and liver metastasis was found. Conclusion The MDCT findings of gastric stromal tumor are relatively specific, and three-phase CT combined with three dimensional reconstruction shows high diagnostic value of this disease.