肝孤立性坏死结节39例分析

Analysis of solitary necrotic nodule of the liver in thirty-nine cases

目的研究肝孤立性坏死结节的临床及影像学特点,提高临床诊断准确率。方法39例均经手术切除和病理证实,分析临床、实验室检查、病理、B超、CT及MRI等表现。结果男性多于女性,病灶多位于肝右叶。23例显示乙型肝炎指标异常,5例乙肝病毒表面抗体阳性。组织病理显示肝脏病灶为凝固性坏死结节,周边为炎性纤维组织带包裹。最小的0.3 cm×0.3 cm,最大的6.5 cm×3.4 cm。B超多呈低回声结节,内回声不均匀。CT平扫为低密度影,增强后约2/3病例无强化。MRI的T1WI多呈低信号,T2WI呈低信号至高信号,大部分病例(15/18)在动脉期、门静脉期及延迟期内部无强化,部分(7/15)边缘有强化,且在延迟期更明显。结论肝孤立性坏死结节临床并不罕见,本组患者多有乙肝病毒指标异常,更应重视与肝癌鉴别诊断。MRI的诊断特异性较强,综合临床和影像学检查,有利于肝孤立性坏死结节的准确诊断。

Objective To investigate the clinical and imaging features of solitary necrotic nodule of the liver （SNN）, to improve the accuracy of diagnosis. Methods Thirty-nine cases of SNN were enrolled in the study from January 2006 to December 2006, and proved by surgery and pathology. The laboratory findings, pathology, and features of ultrasound （US）, computed tomography （CT） and magnetic resonance imaging （MRI） examinations were retrospectively analyzed. Results Over two thirds of the cases was males, and eighty-five percent of the lesions of the SNN occurred in the right lobe of the liver. 23 cases have had viral hepatitis B backgrounds. In the rest patients viral, hepatitis B surface antibody was positive in 5 cases, of which HCV antibody was positive in 1 case. Histopathologically, SNN presented as coagulative necrotic nodules with fibrous capsule which was infiltrated with various inflammatory cells, including lymphocytes, plasma ceils and monocytes. No cirrhosis was showed in all patients. Most lesions were hypoechoic on US. On CT scan the lesions appeared as hypodense lesions and non-enhancing in 2/3 cases. Tl-weighted MRI examinations demonstrated a low intensity lesions, while T2-weighted images demonstrated a low intensity to high intensity lesions. No significant enhancement was recognized on dynamic MRI study in the most cases （15/18）, of which some lesions showed enhanced capsule （7/15）. Conclusion Solitary necrotic nodule of the liver is not a rare clinical disease. However, it is sometimes difficult to diagnose before operation, and because of some patients＇ viral hepatitis B backgrounds it should be emphasized to distinguish from malignant hepatoma. MRI is more specific for diagnosis of the lesion than others. Combination studies, including clinical and imaging examinations, would be useful for the preoperative diagnosis of solitary necrotic nodule of the liver.