Solitary necrotic nodule of the liver.

Solitary necrotic nodule of the liver is a rare benign lesion; only 22 cases have been reported to date. An unsolved problem in treating these lesions involves the difficulties in differential diagnosis; specific features of necrotic nodule of the liver in preoperative examinations have not been identified. Here, we report a patient with resected solitary necrotic nodule of the liver with preoperative features shown on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) examinations. A 48-year-old woman was referred to our hospital on December 13, 1999 because a hypoechoic lesion in Couinaud's segment VIII of the liver had been incidentally detected on US. A CT scan confirmed the presence of a round hypodense lesion, measuring 2 cm in diameter. No significant enhancement was recognized on dynamic MRI study. T1-Weighted MRI examinations demonstrated a low intensity showing a triple-layered pattern with low-iso-low intensity in the lesion, while T2-weighted images demonstrated a slightly high intensity in the lesion. These features suggested fibrous tissue. Histological examinations following partial resection of the liver revealed a solitary necrotic nodule of the liver. Combination studies, including MRI examinations, would be useful for the preoperative diagnosis of a solitary necrotic nodule of the liver.