磁共振成象诊断出血性胆囊炎——离体及活体研究

在离体研究的基础上,对三个出血性胆囊炎的病人术前做出诊断,出血性胆囊炎可分为混合性及非混合性.在离体实验中,如果血液未与胆汁混合,T₁加权象可发现加于10mL胆汁中的0.2mL的血液表现为高信号区;质子密度加权象可发现加于10mL,胆汁中的0.4mL血液表现为稍高信号区;T₂加权象对此不敏感.如果血液与胆汁完全混合,在所有采用的磁共振成象上均使胆汁信号增高.非混合性出血性胆囊炎的磁共振成象具有特征性:在T₁加权象及质子密度加权象胆囊内有高信号区,T₂加权象此区为等信号、低信号或其中心为低信号周围与胆汁相接的为高信号。混合性出血性胆囊炎在所采用的磁共振成象图象中,相对于肝脏,胆囊内容物表现为均匀高信号,临床资料及胆囊壁、胆囊周围渗出有助于这种出血性胆囊炎的诊断.

MRI DIAGNOSIS OF HEMORRHAGIC CHOLECYSTITIS:

Based on the in-vitro study, 3 patients with hemorrhagic cholecystitis were diagnosed preoperatively and hemorrhagic cholecystitis can be subdivided into mixed and non-mixed types. In-vitro experiments show that 0.2mL of blood in 10mL of bile could be detected as a hyperintense area on T1 - weighted image, 0.4mL of blood on proton density weighted image as a slightly hyperintense area if the blood was hot mixed with bile. T2 weighted image was found insensitive in detecting blood in the bile. If the blood miXed with bile completely it increased the sighal intensity of the bile uniformly on all the MR images. The MRI appearance of non-mixed hemorrhagic cholecystitis is pathognomonic, on TI-and proton density - weighted images in the gallbladder there is (are) hyperintense area(areas), on T2-weighted image the area(areas) is (are) isointinse or hypointense in its center and hyperintense in its periphery relative to the surrounding bile. The MRI appearance of mixed hemorrhagic cholecystitis is that relative to the liver, the signal intensity of gallbladder contents is uniformly high on all the MR images. This type of hemorrhagic cholecystitis can be diagnosed with reference of clinical finding and gallbladder wail and pericholecystic effusion.