Hepatic Cavernous Hemangiomas: Relationship between Speed of Intratumoral Enhancement during Dynamic MRI and Apparent Diffusion Coefficient on Diffusion-Weighted Imaging

OBJECTIVE: To investigate the relationships between the apparent diffusion coefficients (ADCs) on diffusion-weighted imaging (DWI) and the speed of contrast-enhancement in hepatic hemangiomas. MATERIALS AND METHODS: Sixty-nine hepatic hemangiomas (> or = 1 cm) were evaluated with DWI, by using multiple b values (b = 50, 400, 800 s/mm2), followed by a gadolinium-enhanced dynamic MRI. The lesions were classified into three groups, according to the speed of contrast-enhancement on the portal phase. ADCs were measured on the ADC map automatically, and were calculated by using the two different b values (mADC50-400 with b values = 50 and 400; mADC400-800 with b values = 400 and 800 s/mm2). RESULTS: The mean ADCs (x 10-3 mm2/s) were significantly higher in the rapid group (1.9 +/- 0.44) than in the intermediate (1.7 +/- 0.35, p = 0.046) or the slow groups (1.4 +/- 0.34, p = 0.002). There were significant differences between the rapid and the slow groups in mADC50-400 (2.12 vs. 1.48; p = 0.008) and mADC400-800 (1.68 vs. 1.22, p = 0.010), and between the rapid and the intermediate groups in mADC50-400 (2.12 vs. 1.79, p = 0.049). Comparing mADC50-400 with mADC400-800, there was a significant difference only in the rapid group (p = 0.001). CONCLUSION: Higher ADCs of rapidly-enhancing hemangiomas may be related to richer intralesional vascular perfusion. Also, the restricted diffusion may be attributed to the difference of structural characteristics of hemangioma.

Burkitt's Lymphoma Representing Periportal Infiltrating Mass on CT

Imaging findings of secondary hepatic lymphoma have been reported as variable, ranging from single or multiple small nodules to diffuse infiltrative tumor patterns. We hear present a rare case report concerning aggressive B cells, secondary Burkitt's lymphoma in non-AIDS demonstrating a surprising periportal lymphoma infiltration, without upper abdominal lymphadenopathy or splenomegaly on the sonography and CT scans. Clinically, the case was characterized by atypical and highly aggressive course, with the patient presenting an abruptly developed obstructive jaundice with rapidly deteriorating hepatic function that could be indicative of cholestatic hepatitis, which differs in its clinical manifestations from hepatic lymphoma without functional deterioration in respect of its non-tissue destructive growth pattern. We suggest that hepatic lymphoma can sometimes be consistent with periportal infiltrating homogeneous mass, with no lymphadenopathy or splenomegaly on the imaging examination, with a predictable aggressive clinical course of the disease and poor prognosis.

Diagnostic Usefulness of MRI for Pulmonary Hamartoma: CT, MRI and Histopathologic Correlations

PURPOSE: To determine the diagnostic usefulness of MRI in pulmonary hamartoma, and the significant MRI features other than fat or characteristic calcification, both revealed by CT. MATERIALS AND METHODS: We prospectively studied chest MR images in five patients with pulmonary hamartoma. All underwent narrow-collimated CT scanning and conventional MRI, specimen MRI was available in three cases. Pulmonary nodular size, shape and margin and the presence of intratumoral fat density, calcification and a cleft-like structure were determined. At MRI, the presence and signal intensity (SI) of the cleft-like structure, including intratumoral cystic space and SI of the main portion of the tumor, were analyzed and compared with the findings of specimen MRI, and correlated with the histopathologic findings. In three cases, the typical enhancement pattern revealed by post-contrast MRI was also evaluated. RESULTS: Narrow-collimated CT scanning revealed fat density or popcorn-shape calcification in two cases and a cleft-like structure in one. The other two cases showed neither fat nor calcification. At MRI, however, all five cases showed a cleft-like structure, which was especially evident on T2WI. The detectability of this did not vary between conventional and specimen MRI. The cleft-like structure showed varying SI on T1, and T2WI correlated to variable mesenchymal component including with respiratory epithelial cells lining the cleft. Marginal rim enhancement was noted on all three post-contrast MR images, and correlated with the relatively rich vascularity of the tumor's marginal portion. An enhanced cleft-like structure was noted in two cases. CONCLUSION: The presence of a cleft-like structure, especially prominent on T2WI and with variable SI, is a useful MR finding for the diagnosis of pulmonary hamartoma, and marginal rim enhancement is an ancillary diagnostic MR finding. In particular, MRI is a useful diagnostic tool in cases where a simple pulmonary nodule demonstrates neither fat nor calcification.

A case of primary diffuse nodular pulmonary amyloidosis localized in the lung / 결핵

Nodular pulmonary amyloidosis is one of the rare manifestation of amyloid disease. It is known to be caused by anyloid L fibrils in the majority of case. We experienced an unusual case of a forty-one year-old woman who was presented with multiple nodular lesion on the chest X-ray. CT-guided core needle bilpsy, performed on the lesion, showed apple green birefringes, when stained Congo red and examined under polarized light. Ultrastructurally, there are randomly oriented, forming densed networks, and consists of fine, 7.5 to 10nm diameter, rigid, non-branching filaments of various lengths in electron-microscopic finding. We report a case of primary diffuse nodular pulmonary amyloidosis only localized in the lung, which was confirmed by CT guided core needle biopsy.

A Case of benign metastasizing leiomyoma in the lung / 결핵

Benign metastasizing leiomyoma usually occurs in women and is associated with a past hysterectomy in 80% of the cases, which is a rare entity. The patient was a 39-year-old woman who complained of cough and sputum. She underwent hysterectomy beacuse of benign leiomyoma ten years age. Chest X-ray showed nodular lesion in the left lung field. Chest CT showed a 3cm sized round well defined mass at left hilum with mild indentation of segmental bronchi of left upper lobe and a small tiny nodule in right lower lung field. Nodular lesion of left upper lobe was resected by thoracotomy.Pathological evaluation showed benign spindle-like cells having nuclei without cytotic atypia similar to those of benign leiomyoma. Immunohistochemical stainings for desmin and smooth muscle actin were positive. Therefore these nodules are considered as benign metastasizing leiomyoma from a uterine leiomyoma. We report this case with the review of literature.