Nobuo Kawauchi

Postaortic left innominate vein: Radiological assessment and pathogenesis

Postaortic left innominate vein (PALIV) is a rare venous anomaly and the findings on plain chest radiographs have not been well described. Plain chest radiographs, CT and MR of nine adults known to have PALIV were reviewed. They all showed a high aortic arch, including four with a right-sided aortic arch and one with a double aortic arch, in postero-anterior radiographs, and seven showed curved shadows in the left upper mediastinum. On all lateral chest radiographs (n = 5), the superior retrosternal region was opacified by the high aortic arch. CT or MR images confirmed the aortic arch and/or innominate artery to be in that part of the retrosternal space, normally occupied by the left innominate vein, in all cases. Association of a curved shadow in the superior mediastinum with a high aortic arch on plain chest radiographs is therefore suggestive of, though not diagnostic for, PALIV. This entity was well documented by CT or MR and the radiological findings were considered to imply that developmentally PALIV is secondary to a high position of the aortic arch.

Hepatocellular Carcinoma: MR Appearance Mimicking Cavernous Hemangioma

A case of hepatocellular carcinoma is reported in which a calculated T2 value of the tumor was exceptionally long and differentiation from cavernous hemangioma based on T2 signal intensity was difficult. Pathologically, the mass consisted of dense, homogeneous acinar formation (pseudoglandular type). The T2 prolongation of the mass was probably due to abundant fluid in the acini.

High-resolution MR imaging evaluation of hepatocellular carcinoma.

Abstract.Purpose: To determine the utility of high-resolution MR imaging for hepatocellular carcinoma. Materials and methods: High-resolution MR images with a 512 matrix in a right to left frequency encoding direction were obtained in 20 consecutive patients with known or suspected hepatocellular carcinoma (HCC). Six series of breath-hold images of the entire liver [T1- and T2-weighted fast spin echo sequences, T1-weighted fast low-angle shot gradient echo sequence and three-phased contrast-enhanced dynamic study using the latter) were obtained using a phased-array multicoil. Results: HCC was depicted in 15 patients on the MR images, and the diagnosis was confirmed at pathology in 13 and at imaging in the other two. In the remaining five patients, HCC was correctly ruled out with MR imaging. Conclusion: High-resolution MR imaging is a promising method in the evaluation of HCC.

Multiple diffuse hemangiomas of the large intestine.

SummaryA 54-year-old male case with multiple, diffuse hemangiomas of the large intestine is described. large diffuse hemangiomas were located at the rectosigmoid and the ascending colon. Some polypoid lesions were located on the transverse colon. Tiny calcifications representing phleboliths were detected in those lesions. No skin hemangiomas were present. Although he did not manifest systemic bleeding tendency, blood examinations demonstrated the presence of mild consumption coagulopathy.

Treatment of unresectable hepatocellular carcinoma less than 2 centimeters by transcatheter arterial chemoembolization with autologous blood clot

Goals To assess the efficacy of transcatheter arterial chemoembolization using autologous blood clot as an embolizing agent (short-TAE [S-TAE]) for the treatment of unresectable hepatocellular carcinoma less than 2 cm. Study Twenty-eight consecutive patients with unresectable hepatocellular carcinoma less than 2 cm in diameter were treated by S-TAE alone. All patients had documented cirrhosis (Child class B:C = 20:8). S-TAE was performed by injecting a mixture of iodized oil and anticancer drugs followed by embolization of hepatic arteries with autologous blood clot. Results A total of 147 sessions of embolization with clots were performed. S-TAE maintained patency of hepatic arteries. The overall survival rates at 1, 3, 5, and 8 years were estimated to be 89%, 52%, 34%, and 17%, respectively, which were better compared with prior records for the gelfoam method. The survival rates for Child class B patients were significantly better than that for Child class C patients (P < 0.05). The Cox proportional hazard model also demonstrated that Child staging of cirrhosis was the sole factor significantly predicting the survival (P < 0.05). Conclusions The long-term outcomes of S-TAE for unresectable hepatocellular carcinoma less than 2 cm are satisfactory. Prognosis of these patients was significantly dependent on clinical stages of coexisting liver cirrhosis.

Pedunculated bronchogenic cyst mimicking pleural lesion.

We report a rare case of a bronchogenic cyst presenting as a pleural nodule. CT and MRI demonstrated a well circumscribed, homogeneous lesion located on the pleural surface apart from the mediastinum. It was proven to be a bronchogenic cyst localized between the parietal and visceral pleurae and connected with the mediastinum only through fibrous tissue. Radiologists should be aware that a mediastinal bronchogenic cyst may be located apart from the mediastinum.

Pseudotumorous enlargement of the paracaval portion of the caudate lobe : a report of two cases with CT and MR appearance

Abstract. The computed tomographic (CT) and magnetic resonance appearance of pseudotumorous enlargement of the paracaval portion (PCP) of the caudate lobe of the liver are presented in two cirrhotic patients. The enlarged PCP was hyperattenuated on precontrast CT and hyperintense on T1-weighted images. The middle and right hepatic veins were displaced around the PCP. The presence of a portal vein branch penetrating the center of the enlarged PCP was important to distinguish it from other hepatic masses in the two patients.

Technical Report: Coaxial Catheter: A New Technique for Sequential Spiral CT During Arterial Portography and Hepatic Arteriography

PURPOSE To evaluate a coaxial catheter method to sequentially acquire spiral-computed tomography (CT) during arterial portography (CTAP) and hepatic arteriography (CTA) at a single transfer. PATIENTS AND METHODS Sixteen patients with malignant hepatic tumours (12 patients with hepatocellular carcinoma, four with metastases) were studied using spiral CT. Depending upon the vascular anatomy revealed by conventional coeliac and superior mesenteric arteriography, an outer and inner catheter were selectively placed to perform CTA and CTAP, respectively. CTAP images were obtained first, while injecting contrast material through an inner catheter followed by the acquisition of the CTA images during injection through an outer catheter. In three patients, the resected specimens were available for comparison with the imaging findings. RESULTS In 12 patients with standard hepatic arterial anatomy, high quality images of CTAP and CTA were obtained. More lesions were detected by the combination of CTAP and CTA than by CTAP or CTA alone in five patients. In one patient with breast carcinoma and a left hepatic artery arising from the left gastric artery, numerous hepatic metastases were delineated on both sets of images. In three patients with replaced or accessory right hepatic arteries, evaluation of the whole liver was difficult on CTA. These procedures were well tolerated by all 16 patients and no complication or technical failure was experienced. CONCLUSION These preliminary data support this new technique as a promising method of performing CTA and CTAP in patients with standard hepatic arterial anatomy with a single catheter insertion.