Hajime Takaki

Mediastinal lymphangiomas in adults : CT findings

Mediastinal lymphangioma is rare in adults, and there are few reports of their computed tomographic (CT) findings. We present the CT results in three cases of mediastinal lymphangioma. One showed a well-defined, multilocular, water-density mass enveloping mediastinal structures, without their displacement or compression; one presented as a well-defined, homogeneous, water-density mass in the right paratracheal region; and one was associated with hemorrhage into cysts and a significant increase in size over 5 years. CT is useful for diagnosis and evaluation of the extent or contents of mediastinal lymphangiomas.

Adrenal nonhyperfunctioning adenoma and nonadenoma: CT attenuation value as discriminative index.

BackgroundWhen an asymptomatic adrenal mass is incidentally discovered on abdominal CT scans, the distinction between a nonhyperfunctioning adenoma and a nonadenoma would be important.MethodsWe evaluated the CT findings of 36 adrenal masses (14 nonhyperfunctioning adenomas, 22 nonadenomas) in 34 patients with no evidence of hormonal hypersecretion. CT attenuation values of adrenal masses on CT scans were calculated by setting a circular region of interest as large as possible in the center of each adrenal mass.ResultsBelow 20 HU in CT attenuation values, all adrenal masses, except one case of ganglioneuroma with myxomatous change, were nonhyperfunctioning adenomas. With an arbitrary threshold of 20 HU, the sensitivity of CT attenuation values in distinguishing nonhyperfunctioning adenomas from nonadenomas was 64%, the specificity was 95%, and the accuracy was 83%. When decreasing the threshold to 15 HU, the sensitivity was 64%, the specificity was 100%, and the accuracy was 86%. The CT attenuation value on noncontrast CT was more useful for making this distinction than the size and interior homogeneity.ConclusionsOur data suggest that an asymptomatic adrenal mass with homogeneous low attenuation (≦15 HU) and less than or equal to 4 cm indicates a nonhyperfunctioning adenoma, and no further examinations are necessary. CT attenuation value on non-contrast CT is the most important discriminatory factor.

Mucin-producing carcinoma of the gallbladder: Imaging demonstration in four cases

We report four cases of mucin-producing carcinoma of the gallbladder (three papillary adenocarcinomas and one mucinous carcinoma), with an emphasis on imaging features. Our findings suggest that when a papillary protrusion or thickened wall, including cystic areas and/or calcifications, is seen radiologically in the enlarged gallbladder, mucin-producing carcinoma of the gallbladder should be included in the differential diagnosis.

Mucin-producing Tumor of the Lung: Ct Findings

Primary lung tumors and pulmonary metastases with a large mucin content are relatively rare, and reports of CT findings are scarce. We present the CT images of patients with mucinous bronchioloalveolar carcinoma and lung metastasis of mucinous adenocarcinoma of the colon. The CT findings include a uniform low attenuation (4.5 and 7.8 HU), irregular margins, and slight enhancement after intravenous injection of contrast medium.

Prospective study of major depressive disorder with white matter hyperintensity: comparison of patients with and without lacunar infarction

ObjectiveTo investigate clinical characteristics, outcome, and risk factor for cerebrovascular disease in patients who had major depressive disorder and white matter hyperintensity (WMHI).MethodA total of 123 new patients diagnosed with major depressive disorder by semi-structured interview underwent magnetic resonance imaging (MRI) and were placed into one of three groups based on results. Patients with no abnormal findings (NF), patients with WMHI and no lacunar infarction (WMHI), and patients with lacunar infarction (LI).ResultsIn the WMHI group, age at initial onset of depression and age at time of interview were both higher than in the NF group, as was severity of depression. Hamilton Rating Scale for Depression (HRSD) scores were significantly higher in the WMHI group than in the NF group. Total WMHI was significantly correlated only with age at initial onset of depression and age at time of interview. In the WMHI group, age at interview was lower than in the LI group and systolic and diastolic blood pressures were lower. Survival analysis regarding the clinical outcome of remission was conducted, but no significant differences were discovered among the three groups, WMHI, LI, and NF. However, the suicide rate was significantly higher in the LI group than in the other two groups.ConclusionsThe origin and clinical characteristics of depression accompanied by WMHI may be specific; additional stringent study in comparison with individuals with LI is needed.

Pulmonary thin-section CT findings in acute Moraxella catarrhalis pulmonary infection

OBJECTIVE Moraxella catarrhalis is an important pathogen in the exacerbation of chronic obstructive pulmonary disease. The aim of this study was to assess the clinical and pulmonary thin-section CT findings in patients with acute M. catarrhalis pulmonary infection. METHODS Thin-section CT scans obtained between January 2004 and March 2009 from 292 patients with acute M. catarrhalis pulmonary infection were retrospectively evaluated. Clinical and pulmonary CT findings in the patients were assessed. Patients with concurrent infection including Streptococcus pneumoniae (n = 72), Haemophilus influenzae (n = 61) or multiple pathogens were excluded from this study. RESULTS The study group comprised 109 patients (66 male, 43 female; age range 28-102 years; mean age 74.9 years). Among the 109 patients, 34 had community-acquired and 75 had nosocomial infections. Underlying diseases included pulmonary emphysema (n = 74), cardiovascular disease (n = 44) or malignant disease (n = 41). Abnormal findings were seen on CT scans in all patients and included ground-glass opacity (n = 99), bronchial wall thickening (n = 85) and centrilobular nodules (n = 79). These abnormalities were predominantly seen in the peripheral lung parenchyma (n = 99). Pleural effusion was found in eight patients. No patients had mediastinal and/or hilar lymph node enlargement. CONCLUSIONS M. catarrhalis pulmonary infection was observed in elderly patients, often in combination with pulmonary emphysema. CT manifestations of infection were mainly ground-glass opacity, bronchial wall thickening and centilobular nodules.

Extrahepatic Bile Duct Cancer: Invasion of the Posterior Hepatic Plexuses—Evaluation Using Multidetector CT

PURPOSE To assess the utility of axial and coronal reformatted multidetector computed tomographic (CT) images in the evaluation of the invasion of posterior hepatic plexuses by extrahepatic bile duct cancer. MATERIALS AND METHODS This retrospective study was approved by the institutional review board, and informed consent was waived. Forty-three patients (22 men, 21 women; age range, 40-80 years; mean age, 65 years) with surgically resected cancer involving the extrahepatic bile duct between December 2004 and September 2010 were included. Posterior hepatic plexus 1 runs from the superior and middle bile duct to the right celiac ganglion, and posterior hepatic plexus 2 runs between the lower bile duct and right celiac ganglion behind the portal vein. Invasion of the posterior hepatic plexuses was elucidated by using pathologic and postoperative multidetector CT findings. Three radiologists independently evaluated the preoperative axial and coronal reformatted images with a separate viewing session for the invasion of posterior hepatic plexuses that was detected on the basis of the presence of increased attenuation of fat tissue along the nerve routes. Receiver operating characteristic analysis was performed to compare the diagnostic performance of the two image interpretations. RESULTS Invasion of posterior hepatic plexus 1 and of posterior hepatic plexus 2 was recognized in 10 (23%) and nine (21%) of 43 patients, respectively. The diagnostic performance of coronal reformatted image interpretation was significantly greater than that for axial image interpretation (mean area under the curve, 0.99 vs 0.89, P = .04; mean accuracy, 95% vs 82%, P = .003). In all reviewers, one false-positive diagnosis of the invasion of posterior hepatic plexus occurred on axial and/or coronal image display types because of fibrosis and inflammatory cell infiltration along these plexus routes. CONCLUSION Coronal reformatted images can be useful for accurate diagnosis of the invasion of posterior hepatic plexuses and may facilitate surgical decision making in regard to the resection of celiac ganglion.

Chest High-resolution Computed Tomography Findings in 601 Patients with Inflammatory Bowel Diseases

RATIONALE AND OBJECTIVES Pulmonary involvement in inflammatory bowel disease may reflect the common embryonic origin of the gastrointestinal tract and the bronchial tree. No studies have compared pulmonary high-resolution computed tomography (HRCT) findings between ulcerative colitis (UC) and Crohn disease (CD). This study aimed to assess the relationship between pulmonary HRCT findings and inflammatory bowel disease activity and to compare HRCT findings between UC and CD. MATERIALS AND METHODS We retrospectively identified 601 consecutive patients (350 with UC and 251 with CD) who had undergone chest HRCT examinations at our institutions between April 2004 and April 2016. Parenchymal abnormalities, enlarged lymph nodes, and pleural effusion were evaluated on HRCT. RESULTS One hundred sixty-seven patients (94 men, 73 women; aged 12-86 years, mean: 47.2 years) with UC and 93 patients (61 men, 32 women; aged 12-71 years, mean: 37.9 years) with CD had abnormal findings on chest HRCT. The HRCT findings of UC and CD mainly consisted of centrilobular nodules (in 49.1% and 45.2% of cases, respectively) and bronchial wall thickening (in 31.7% and 54.8%, respectively). There was no relationship between HRCT findings and disease activity. Bronchial wall thickening was significantly more frequent in patients with CD than in those with UC (P < .001). CONCLUSION The main chest HRCT findings in UC and CD are centrilobular nodules and bronchial wall thickening. There are differences in HRCT findings between UC and CD.