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Biomedical subjects

N Hayabuchi

Publications and source records attributed to N Hayabuchi.

104 records · Page 6Linked to original sources
PubMedDate not supplied

Lung cyst formation in lymphocytic interstitial pneumonia: CT features.

OBJECTIVE: We performed this study to identify and characterize the CT findings of lymphocytic interstitial pneumonia (LIP). MATERIALS AND METHODS: The CT findings of two patients with LIP were reviewed and correlated with their histologic specimens. RESULTS: Chest CT of the two patients showed areas of increased attenuation in both lung fields which were associated with nodular and cystic lesions surrounding the peribronchovascular bundles. The most characteristic abnormality identified on CT was the presence of multiple cysts throughout both lungs. Macroscopic findings of lung biopsy specimens included multiple nodular and cystic lesions. CONCLUSION: This description of multiple pulmonary cysts formation in LIP is new.

Adult↗
PubMedDate not supplied

Three-dimensional imaging of liver tumors using helical CT during intravenous injection of contrast medium.

PURPOSE: The goal of this work was to determine whether 3D reconstruction of images from CT during intravenous injection of contrast medium, performed in tandem with advanced rendering algorithms, could accurately depict major anatomic structures and hepatic tumors. METHOD: Thirty-one patients (22 with hepatocellular carcinoma, 8 with metastatic lesions, and 1 with intrahepatic cholangiocarcinoma) underwent CT imaging. Twenty-three of the 31 patients underwent needle biopsy or surgery, yielding a histologic diagnosis. The remaining eight patients were diagnosed from imaging findings and laboratory data. We compared the ability of maximum intensity projection (MIP) and volume-rendered technique (VRT) images to depict the hepatic veins and intrahepatic portal veins. RESULTS: Both MIP and VRT depicted the course of vessels up to the second or third branches. The techniques did not significantly differ. In this regard, in most cases, visualization of the liver surface and tumor was excellent with VRT images. CONCLUSION: Volume-rendered 3D-CT images during intravenous injection without the MIP technique produced 3D images of high quality with excellent visualization of tumors and their relationships to vital structures.

Adult↗
PubMedDate not supplied

Intrahepatic peripheral cholangiocarcinoma: comparison of dynamic CT and dynamic MRI.

PURPOSE: The purpose of this work was to compare dynamic MRI (D-MRI) with dynamic CT (D-CT) for the diagnosis of peripheral cholangiocarcinoma (PCC) of the liver. METHOD: Twenty patients with PCC underwent both D-CT and D-MRI during the early, middle, and delayed phase after contrast medium administration. The findings from D-MRI were compared with those from D-CT. RESULTS: D-CT and D-MRI exhibited a similar tumoral enhancement pattern, and this enhancement was more conspicuous on D-MRI. A wedge-like enhancement area peripheral to the tumor was observed in 9 (45%) patients on D-CT and 11 (55%) patients on D-MRI. Ductal dilatation was found in 13 (65%) patients on both techniques. Vascular involvement and extrahepatic invasion were seen in nine (45%) and two (10%) patients, respectively. The relationship of the tumor to the vessels and surrounding organs was more easily evaluated on D-CT. CONCLUSION: Both D-CT and D-MRI can provide important information for the diagnosis of PCC. D-CT is better than D-MRI for demonstrating vascular involvement and extrahepatic invasion. D-MRI gives more conspicuous enhancement.

Aged↗
PubMedDate not supplied

MRI of ganglioneuroma: histologic correlation study.

PURPOSE: The purpose of this study was to evaluate the MR findings of ganglioneuroma and to correlate imaging and histologic features. METHOD: Conventional SE and contrast-enhanced dynamic MRI was used to examine 10 patients with pathologically confirmed ganglioneuroma. The morphologic features, signal intensity, and dynamic enhancement pattern of the tumors were retrospectively analyzed and correlated with histologic features. RESULTS: Capsules were present in all tumors histologically and were also detected in five tumors on postcontrast T1-weighted images. A whorled appearance corresponding to interlacing bundles of Schwann cells and collagen fibers on histologic specimens was visualized in five tumors on T1-and/or T2-weighted images. Tumors with markedly high signal intensity on T2-weighted images consisted histologically of a large amount of myxoid stroma and relatively few cellular and fibrous components. Tumors with intermediate to high signal intensity consisted of numerous cellular and fibrous components and little myxoid stroma. Early enhancement of tumors was usually lacking in dynamic MR studies; however enhancement gradually increased. CONCLUSION: The results suggest that the MR features of ganglioneuroma are well correlated with histologic findings.

Adolescent↗
PubMedDate not supplied

MR imaging of soft-tissue masses of the extraperitoneal spaces.

Magnetic resonance (MR) imaging has an increasing role in evaluating soft-tissue masses of the extraperitoneal spaces. Since the MR imaging features of most soft-tissue masses are nonspecific, prediction of a specific histologic diagnosis remains a challenge for the radiologist. However, there are certain specific MR imaging appearances that are helpful for more accurate diagnosis. Some histologic components, such as myxoid stroma, collagen fibers, calcification, and fat, have characteristic MR imaging features. Recognition of these features can assist the radiologist in limiting the differential diagnosis. Dynamic enhancement patterns can reflect the vascularity of masses and may be useful in diagnosis, especially in differentiating benign from malignant soft-tissue masses. Familiarity with specific signs and knowledge of diagnostic pitfalls are also important for shortening the list of differential diagnoses. Specific signs are the target sign, the bowl of fruit sign, a whorled appearance, a flow void, speckled enhancement, associated lymphadenopathy, and extension into the intervertebral foramen. Diagnostic pitfalls are as follows: a myxoid stroma simulating cystic degeneration and necrosis, collagen fibers simulating hemorrhage, a fat component simulating extraperitoneal fat, extensive intratumoral hemorrhage simulating hematoma, benign masses mimicking malignant ones, malignant masses mimicking benign ones, and peritoneal lesions mimicking extraperitoneal masses.

Contrast Media↗
PubMedDate not supplied

Antineoplaston treatment for advanced hepatocellular carcinoma.

Antineoplaston A10 injection (antineoplaston A10 I) exhibited cystostatic growth inhibition of human hepatocellular carcinoma (HCC) cells in vitro and showed minimum adverse effects in a phase I clinical trial. Advanced HCC is hard to control because the potent anticancer drugs or embolizations easily induce hepatic failure. We review herein 2 cases of advanced HCC treated with antineoplaston A10 I. Both cases showed interesting responses to antineoplaston A10 I. One showed massive coagulation necrosis of tumors after intra-arterial infusion of antineoplaston A10 I and the other showed resolution of portal vein tumor thrombosis with systemic infusion of antineoplaston A10 I. The usefulness of anti-neoplaston A10 I in terminal staged HCC is discussed.

Aged↗
PubMedDate not supplied

Applicability and advantages of flow artifact-insensitive fluid-attenuated inversion-recovery MR sequences for imaging the posterior fossa.

We describe a new sequence, flow artifact-insensitive fluid-attenuated inversion recovery (FAIS-FLAIR), that capitalizes on the advantages of fluid-attenuated inversion recovery (FLAIR) while minimizing FLAIR-related artifacts such as those often encountered in the posterior fossa. Twenty-eight patients with posterior fossa disease underwent FAIS-FLAIR, conventional FLAIR, and spin-echo MR studies, and the findings yielded by the three techniques were compared. In this patient population, postcontrast FAIS-FLAIR imaging was obtained in 20 patients and compared with postcontrast T1-weighted images. The images were assessed for lesion conspicuity by three radiologists. FAIS-FLAIR markedly reduces the inflow artifacts from noninverted CSF on FLAIR images. It does so with and without contrast agent administration, and produces higher lesion conspicuity compared with T1- and T2-weighted spin-echo sequences and conventional FLAIR images of the posterior fossa.

Artifacts↗
PubMedDate not supplied

Problems in radiographic detection and diagnosis of lung cancer.

All chest radiographs of 107 proven lung cancer patients who received consecutive biennial chest radiography were reviewed to elucidate problems detecting their cancers, and diagnosing them when initially radiographically detected. Subjects, members of a fixed population sample, originally numbered 20,000 persons, 17,000 of whom consistently received consecutive biennial chest radiography during examinations for late effects of atomic-bomb radiation. Among the 107 subjects, 64 had radiographic manifestations of cancer; 47 were initially correctly diagnosed; 17 were not. Eleven of the 17 were initially equivocal, diagnosable only after subsequent radiography and retrospective review of serial radiographs. Diagnostic problems consisted of 1) six detection errors with cancer images superimposed on musculoskeletal and cardiovascular structures, reducible by stereoscopic p.a. instead of single p.a. radiography; immediate tentative interpretations; and by comparing earlier with current radiographs. 2) Eight decision errors, wherein cancers mimicked other diseases, were reducible by greater index of suspicion and scrutiny during interpretations.

Diagnostic Errors↗
PubMedDate not supplied

Non-Hodgkin's lymphomas involving Waldeyer's ring: a proposal for clinical categorization.

The clinicopathologic data of 97 patients with non-Hodgkin's lymphomas involving Waldeyer's ring were retrospectively reviewed. Age, sex, the site of involvement within Waldeyer's ring, and Rappaport's histological classification played little role in the prognosis. Although the Ann Arbor staging classification was the only factor that correlated with the patients' prognoses (stage I vs stage II, p less than 0.01; stage II vs stage III + IV, p less than 0.02), it is not considered the ideal classification. The survival rates of stage II patients, who comprised about 60% of the entire group, was quite different due to their cervical node status. That is, 33 patients with bulky cervical nodes (4 cm in diameter or more) or bilateral cervical nodes had significantly poorer survival rates than 24 patients with small unilateral cervical nodes (p less than 0.001). The survival curve of the former group was similar to that of the stage III and IV patients, whereas the survival curve of the latter group was similar to that of the stage I patients. Lymphography, which was performed for 72 patients in this series, is not considered essential. From these results, we recommend the categorization of patients with malignant lymphomas involving Waldeyer's ring into two major groups according to cervical and inguinal node status in order to assess treatment methods. That is, patients with bulky or bilateral cervical lymph nodes or those with inguinal lymphadenopathy and patients without any lymphadenopathy or those with minimal unilateral cervical nodes alone.

Adult↗
PubMedDate not supplied

Synovial sarcoma arising from the chest wall: MR imaging findings.

We report a case of synovial sarcoma of the chest wall in a 41-year-old man. Chest CT revealed a huge tumor of the left chest wall with heterogeneous enhancement. On MR imaging, the tumor showed the "bowl-of-fruit" mixed-signal appearance with fluid-fluid levels similar to those of synovial sarcoma of the extremities. Synovial sarcoma arising from the chest wall is extremely rare; only four cases have been reported in the English literature. As synovial sarcoma is considered a carcinosarcoma-like tumor with true epithelial differentiation, it is able to originate from various regions. Even if the tumor is found in a region distant from the synovial membrane, the differential diagnosis of a tumor which demonstrates such findings on MR imaging should include synovial sarcoma.

Adult↗
PubMedDate not supplied

Endovascular management of an aneurysm arising from posterior inferior cerebellar artery originated at the level of C2.

A 22-year-old man was admitted with a spontaneous subarachnoid hemorrhage. Right vertebral angiography demonstrated an aneurysm arising from a distal segment of an anomalous posterior inferior cerebellar artery (PICA) at the level of C 1. The PICA originated from the third segment of the vertebral artery at the level of C2. The lesion was treated with endovascular techniques, and the patient suffered no residual neurological deficits.

Adult↗
PubMedDate not supplied

Anomalous systemic arterial supply to the basal segment of the left lung: demonstration using MR angiography.

In a 41-year-old man with an abnormal left lower lobe opacity on a chest radiograph, magnetic resonance (MR) angiography showed a large abnormal vessel extending from the left side of the descending thoracic aorta, supplying the left lower lobe. Furthermore, the lung parenchyma showed no evidence of sequestrated lung. This entity corresponded to type-I of intralobar pulmonary sequestration, as classified by Pryce.

Adult↗