Biomedical subjects

Masataka Uetani

Publications and source records attributed to Masataka Uetani.

24 records · Page 2Linked to original sources

PubMed2002

Sarcoidosis of the breast.

We report a case of sarcoidosis of the breast in a 31-year-old woman who presented with a palpable breast mass. The mammography showed a spiculated mass without any microcalcifications. Ultrasonogram showed a hypoechoic mass. Computed tomography showed a spiculated nodule. T2-weighted MR images with fat-suppression technique showed a mass with irregular border that appeared to be an accumulation of small nodules. Gadolinium-enhanced dynamic study showed gradually increasing signal intensity. She underwent excisional biopsy and the pathological findings were consistent with that of sarcoidosis. The MRI findings were well correlated with histopathological appearance.

Adult↗

PubMed2002

Role of magnetic resonance imaging in the assessment of disease activity in thyroid-associated ophthalmopathy.

Two different phases in disease activity are observed during the clinical course of thyroid-associated ophthalmopathy (TAO). The assessment of disease activity is important for predicting the outcome of medical management because medical treatment can be effective in the active stage. The aim of this study was to investigate whether magnetic resonance imaging (MRI) could assess the disease activity in TAO. To investigate the relation between MRI-T2 signal intensity (SI) and extraocular muscle (EOM) size, 11 patients with TAO were evaluated. EOM sizes (enlargement, volume) were measured by MRI-T1 image. T2-SI of EOM was expressed as a percentage of temporal muscle. The reduction in T2-SI was significantly positively correlated with that of EOM enlargement after treatment. Additionally, T2-SI in pretreatment showed a significant correlation with reduction in EOM volume for therapeutic effect, which indicates T2-SI in pretreatment can be one of the reliable parameters for predicting the therapeutic outcome of treatment. To investigate whether MRI-T2 pattern could predict the reversibility of diplopia, 28 patients with Graves' disease with or without ophthalmopathy were evaluated. Patients with TAO with reversible diplopia showed an uniform T2 pattern in enlarged EOM. However, in patients with irreversible diplopia caused by the mechanical limitation of EOM, MRI-T2 image showed no uniformity with a partial appearance of low T2-SI. The partial low T2-SI may indicate the progress of inactive (fibrotic) change in EOM after active (inflammatory) change. In conclusion, MRI is a useful tool for detection not only of EOM enlargement, but also disease activity in TAO. MRI-T2 SI and pattern can predict the outcome of medical management in TAO.

Adult↗

PubMed2002

Diffusion-weighted echoplanar MR imaging of the salivary glands.

OBJECTIVE: We determined the apparent diffusion coefficients of normal and dysfunctional salivary glands. SUBJECTS AND METHODS: A diffusion-weighted single-shot spin-echo type of echoplanar MR imaging was performed on the parotid or submandibular glands, or both, in 36 healthy subjects, 20 patients with Sjögren's syndrome, and six patients with sialoadenitis. The apparent diffusion coefficient of the salivary gland was calculated using two b factors (b = 500 and 1,000 sec/mm(2)). RESULTS: The apparent diffusion coefficient was lower in the parotid glands (0.28 x 10(-3) mm(2)/sec) than that of the submandibular glands (0.37 x 10(-3) mm(2)/sec). The apparent diffusion coefficient was increased in sialoadenitis, whereas it decreased with abscess formation. The apparent diffusion coefficients of the parotid glands in patients with Sjögren's syndrome correlated with the salivary flow rates but not with the sialographic gradings of the glands. We also found a correlation of the decreases in apparent diffusion coefficients with the severity of gland damage as assessed on T1-weighted MR images. CONCLUSION: Diffusion-weighted echoplanar MR imaging may reveal diseased states of the salivary glands.

Adult↗

PubMedDate not supplied

Esophageal and bronchial perforations after thoracic aortic aneurysm replacement: successful repair with covered metallic stents.

Esophageal and bronchial perforations are rare but potentially fatal complications of descending thoracic aortic aneurysm replacement. This report presents a 67-year-old man with both esophageal and bronchial perforations that occurred after descending thoracic aortic aneurysm replacement. Surgical repair was performed, but the lesions perforated again. Two covered metallic stent prostheses introduced into both the esophagus and left main bronchus led to the improvement of mediastinitis by sealing the perforations. To our knowledge, this is the first report describing successful treatment for esophageal and bronchial perforations using covered metallic stents. Placement of covered metallic stents can be an option for the treatment of patients with esophagorespiratory tract perforations, especially those who are in critical condition.

Aged↗

PubMedDate not supplied

CT findings of ruptured intramural hematoma of the aorta extending along the pulmonary artery.

Mediastinal hematoma extending along the pulmonary artery is a rare complication of Stanford type A classic (double-barreled) aortic dissection. Rupture from the posterior aspect of the aortic root penetrates the shared adventitia of the aorta and pulmonary artery. From this location, hematoma can spread along the adventitial planes of the pulmonary arteries out into the lungs. We report a case of ruptured intramural hematoma of the aorta (IMH) extending along the pulmonary artery. To our knowledge, this finding in patients with IMH has not been reported in the literature.

Aged, 80 and over↗

PubMedDate not supplied

Subchondral insufficiency fracture of the femoral head: magnetic resonance imaging findings correlated with micro-computed tomography and histopathology.

We described magnetic resonance (MR) imaging findings of subchondral insufficiency fracture of the femoral head without collapse in which micro-computed tomography (CT) and histopathologic studies were performed. Magnetic resonance imaging showed a subchondral low-signal intensity band, which corresponded to the fracture callus. Diffuse bone marrow edema with contrast enhancement effect was seen in both the proximal and distal segments of the low-signal intensity band. These features are distinct from those of avascular necrosis.

Aged↗