Hatsuko Nasu

Analysis of anatomic variants of mesenteric veins by 3-dimensional portography using multidetector-row computed tomography

BACKGROUND It is important to be aware of mesenteric venous variants to perform peripancreatic surgery. We investigated the usefulness of 3-dimensional (3-D) portography. METHODS Vessels were reconstructed using computer software in 102 patients undergoing multidetector-row computed tomography (MDCT) scheduled for gastrointestinal or hepatobiliary-pancreatic surgery. RESULTS The superior mesenteric vein (SMV) was composed of single and double trunks around the splenoportal confluence in 78 and 24 patients, respectively. The inferior mesenteric vein joined the splenic vein (68.5%), SMV (18.5%), and splenoportal confluence (7.6%). The left gastric vein joined the splenic vein (46.3%), portal vein (39.0%), and splenoportal confluence (14.7%). Seventy-nine patients showed a gastrocolic trunk, mostly composed of the right gastroepiploic vein and veins from the colonic hepatic flexure. Intraoperative findings were identical to 3-D diagnosis in 68 gastrectomized and 9 pancreatectomized patients. CONCLUSION Although mesenteric venous tributaries are complex, 3-D portography is helpful for surgeons to safely perform peripancreatic surgery.

Time-resolved optical mammography and its preliminary clinical results.

We have been developing an optical mammography prototype consisting of a multi-channel time-resolved spectroscopy system for breast cancer screening. The system utilizes the time-correlated single photon counting method, and the detector modules and the signal processing circuits were custom-made to obtain a high signal to noise ratio and high temperature stability with a high temporal resolution. Pulsed light generated by a Ti: Sapphire laser was irradiated to the breast, and the transmitted light was collected by optical fibers placed on the surface of a hemispherical gantry filled with an optical matching fluid. To reconstruct a 3D image of the breast, we employed a method using a time-resolved photon path distribution based on the assumption that scattering and absorption are independent of each other. We verified the possibility of human breast imaging by using a three-dimensional phantom model, which provides a simulation of human breast cancer, in the gantry. The clinical study was also started in January 2007. In a comparative study with conventional modalities, the breast cancers were detected as regions of optically higher absorption. Moreover, the results suggest that optical mammography is useful in monitoring the effects of chemotherapy.

Scanning acoustic microscopy for characterization of neoplastic and inflammatory lesions of lymph nodes

A scanning acoustic microscope (SAM) imaging system calculates and color codes speed of sound (SOS). We evaluated the SAM results for lymph node imaging and compared these results with those of light microscopy (LM). SAM showed normal structures and localized/diffuse lesions of the lymph node. Our results revealed that as a rule, soft areas such as cystic necrosis presented less SOS while harder areas such as coagulative necrosis, granulomas, and fibrosis exhibited greater SOS. SOS increased according to stromal desmoplastic reactions and cellular concentration. In neoplastic lesions, statistically significant differences in SOS were observed among scirrhous carcinomas, lymphomas, and medullary carcinomas. SAM provided the following benefits over LM: (1) images reflected the tissue elasticity of each lesion, (2) digitized SOS data could be statistically comparable, (3) images were acquired in a few minutes without special staining, (4) SAM images and echographic images were comparable for clinical ultrasound imaging study.

Analysis of intrahepatic venovenous shunt by hepatic venography

BACKGROUND The necessity of preserving hepatic venous drainage in hepatectomy and liver transplantation has recently been accepted; however, the hepatic vein (HV) can be removed when an effective intrahepatic venovenous shunt (VV shunt) exists. METHODS Occlusion venography of the right HV (RHV) was performed in 51 patients to investigate the VV shunt characteristics. RESULTS Twenty patients had a shunt between the RHV and large HVs whose root diameters were >3 mm, such as the superficial or inferior RHV, or the middle HV. Twenty patients had a shunt between the RHV and small HVs with root diameters < or =3 mm. Eleven patients had no shunt. The change in anterior portal vein blood flow after RHV occlusion, evaluated by Doppler ultrasonography, was minimal (5 +/- 3%) in patients with a shunt between the RHV and large HVs, and less than in patients with a shunt between the RHV and small HVs (38% +/- 18%) or without a shunt (50% +/- 17%; P < .0001). A shunt between the RHV and large HV was less frequently seen in those patients with cirrhosis (3/20) than in those without cirrhosis (17/31; P = .0044). The existence of the shunt between the RHV and large HVs was unpredictable, however, from computed tomographic findings or laboratory data. CONCLUSION A hemodynamically significant VV shunt between the RHV and large HV was observed in fewer than half of the patients and less frequently in cirrhotic patients. Preservation of hepatic venous drainage should be considered in patients without a hemodynamically significant VV shunt in liver surgery.

Tumor enhancement using Mn-metalloporphyrin in mice: Magnetic resonance imaging and histopathologic correlation

To determine the signal enhancement characteristics of tumors after administration of a metalloporphyrin derivative, HOP‐9P (13, 17‐bis (1‐carboxypropionyl) carbamoylethyl‐3, 8‐bis (1‐phenylpropyloxyethyl)‐2, 7, 12, 18‐tetramethyl‐porphyrinato manganese (III)) and to determine whether HOP‐9P is tumor‐necrosis specific.

Feasibility of magnetic resonance elastography for the pancreas at 3T.

1) To assess the usefulness of an elastic belt bracing the upper abdomen for reducing the miscalculated areas of the pancreas on 3.0T magnetic resonance elastography (MRE); 2) to test whether MRE can detect difference of stiffness between normal pancreas and the focal pancreatic diseases.

Double neuroendocrine ductal carcinomas in situ coexisting with a background of diffuse idiopathic neuroendocrine cell hyperplasia of breast: A case report and hypothesis of neuroendocrine tumor development

This article reports the case of a 72‐year‐old woman with two nodules of neuroendocrine (NE) ductal carcinoma in situ coexistent with a background of NE cell hyperplasia. Both tumors, 15 and 3 mm in size, were incidentally revealed on computed tomography without any apparent clinical symptoms. The tumors showed similar histological features, and more than 50% of the tumor cells patchily expressed NE markers, such as chromogranin A, synaptophysin, CD56, and somatostatin receptor type 2. The surrounding nontumor ductal cells also showed spotty or linear positivity for NE markers in contrast to the cells of normal atrophic breasts, which rarely present with NE cells. Moreover, focal mucin production was also observed in the peripheral ducts. It is hypothesized that idiopathic breast NE cell hyperplasia with multiple small nests of NE cells may extend to form a true mass of NE neoplasms.

Atypically enhanced cavernous hemangiomas of the liver: centrifugal enhancement does not preclude the diagnosis of hepatic hemangioma

The imaging features of an atypically enhanced hepatic hemangioma have not been well described in the literature, and the presence of such atypia may sometimes cause clinical problems in the differential diagnosis. Herein, we report a case of hepatic hemangioma demonstrating a previously unreported atypical enhancement pattern. On dynamic computed tomography during hepatic arteriography, a centrifugal enhancement pattern and subsequent peritumoral ring-shaped enhancement mimicking corona enhancement were found in cavernous hemangiomas of the liver in a 68-year-old Japanese man. Histopathological diagnosis of cavernous hemangioma of the liver was made on a biopsy specimen. Considering the importance of differentiating benign hepatic tumor from various forms of malignancy, radiologists and hepatologists should be aware of rare enhancement patterns sometimes seen in hepatic hemangioma. Establishing knowledge of the entire spectrum of atypical hepatic hemangioma may benefit the rational approach to future cases.

Breast cancer metastatic to the kidney with renal vein involvement

The common sites of breast cancer metastases include bones, lung, brain, and liver. Renal metastasis from the breast is rare. We report a case of breast cancer metastatic to the kidney with extension into the renal vein. A 40-year-old woman had undergone left mastectomy for breast cancer at the age of 38. A gastric tumor, which was later proved to be metastasis from breast cancer, was detected by endoscopy. Computed tomography performed for further examination of the gastric tumor revealed a large left renal tumor with extension into the left renal vein. It mimicked a primary renal tumor. Percutaneous biopsy of the renal tumor confirmed metastasis from breast cancer. Surgical intervention of the stomach and the kidney was avoided, and she was treated with systemic chemotherapy. Breast cancer metastatic to the kidney may present a solitary renal mass with extension into the renal vein, which mimics a primary renal tumor.

Two cases of diabetic mastopathy: MR imaging and pathological correlation

Diabetic mastopathy is a rare benign condition associated with long-standing diabetes mellitus and presents with breast lumps. This report describes two cases in which diffusion-weighted images (DWI) on magnetic resonance imaging were quite different from each other. In case 1, there were hyperintense lesions on DWI, and surgically removed specimens revealed ductitis with marked lymphocytic infiltration. In case 2, no abnormal intensity was depicted on DWI, and biopsy specimens showed dense stromal fibrosis with mild perivascular lymphocytic infiltration that corresponded to previous reports. Although it is reported that diabetic mastopathy is composed of dense fibrous tissue with low cellularity that results in no hyperintense lesion on DWI, in cases with marked lymphocytic infiltration, strong hyperintensity can be seen on DWI mimicking malignant breast tumors.