Capillary hemangioma arising from the lesser omentum in an adult: A case report.

RATIONALE: Although capillary hemangiomas, common lesions involving the proliferation of small capillary vessels and a single layer of endothelial cells, can arise in any organ, they are rarely reported in the greater or lesser omentum. Here in, we report a case of capillary hemangioma arising from the lesser omentum in an adult with interesting diagnostic imaging findings, including changes in tumor size over time on computed tomography (CT), that was resected using laparoscopic surgery. To our knowledge, this is the first English report to describe a capillary hemangioma arising from the lesser omentum. PATIENT CONCERNS: A 63-year-old Japanese man received hemodialysis for chronic renal failure due to diabetic nephropathy, and a small, gradually enlarging tissue mass was found near the lesser curvature of the stomach on plain CT performed annually, without any associated complaints. Diagnostic imaging revealed an 18 × 15-mm tumor with a homogenous, highly enhanced effect in the early phase that was attenuated but prolonged in the delayed phase. Magnetic resonance imaging showed a mass with low signal intensity on T1-weighted imaging and relatively high signal intensity on T2-weighted imaging. DIAGNOSIS: The patient was diagnosed with capillary hemangioma arising from the lesser omentum according to the pathological and immunohistological findings. INTERVENTIONS: The patient underwent laparoscopy for excision of the tumor from the lesser omentum. OUTCOMES: At the 1 year follow-up, the patient had no recurrence of the tumor. LESSONS: We describe the first case worldwide of capillary hemangioma that was a true vascular tumor arising from the lesser omentum. Although capillary hemangioma arising from the lesser omentum is extremely rare, it should be considered in the differential diagnosis of patients presenting with a highly enhanced lesser omental tumor, and laparoscopy can be safely applied for the excision of this tumor.

Diagnosis of incarcerated intramesosigmoid hernia aided by multiplanar reconstruction images of multidetector computed tomography: a case report.

BACKGROUND: Internal hernia is a rare cause of intestinal obstruction, and sigmoid mesocolon hernia is an extremely rare form of this condition. Among sigmoid mesocolon hernias, intramesosigmoid hernia is the least frequent subtype. We described a case of intramesosigmoid hernia through the orifice on the right leaf of the mesosigmoid with an incarcerated ileum of 6 cm in length without strangulation. This case was diagnosed by multidetector computed tomography with multiplanar reconstruction images and treated without resection of the small intestine in a 52-year-old man with characteristic diagnostic images. CASE PRESENTATION: A 52-year-old man suffering periumbilical cramping pain with sudden onset that had persisted for 1 week without recovery was referred to Fukui Katsuyama General Hospital. Multidetector computed tomography revealed small bowel obstruction, and an incarcerated short intestinal loop was revealed by sagittal slices of the multiplanar reconstruction images of the routine study of the left side of the pelvic space. Sagittal multiplanar reconstruction images also showed narrow belt-shaped fluid retention contacting the tip of the incarcerated short loop toward the cranial direction localized in the mesosigmoid. These findings indicated that the fluid and the herniated small bowel were wrapped together in the mesosigmoid, which was characteristic of intramesosigmoid hernia. The patient underwent laparotomy operation 2 days after admission. The ileum, which was approximately 75 cm proximal to the ileocecal junction and herniated into the mesosigmoid through the right leaf, was released without resection. The orifice located in the central part of the right leaf was oval shaped and measured less than 2 cm in diameter. The left leaf of the mesosigmoid was intact. The orifice of the right lobe was closed by suture. The patient showed an uneventful recovery. CONCLUSION: We report an extremely rare case of incarcerated intramesosigmoid hernia that was diagnosed by multidetector computed tomography with multiplanar reconstruction images. The finding of narrow belt-shaped fluid retention contacting the tip of the incarcerated short intestinal loop is characteristic of intramesosigmoid hernia and will be useful for conclusively differentiating this disease from transmesosigmoid hernia. Although intramesosigmoid hernia is a rare cause of internal hernia, multidetector computed tomography and multiplanar reconstruction images can provide the characteristic findings and proved useful for the precise preoperative diagnosis and treatment of intramesosigmoid hernia.

Winged scapula in patients with myotonic dystrophy type 1.

We report two patients with myotonic dystrophy type 1 (DM1) showing winged scapula in a single family. Genomic analysis revealed a marked expansion of CTG repeats in the 3' untranslated region; 1100 in patient 1 and 667 in patient 2. Muscle MRI revealed marked atrophy in the serratus anterior muscle in both patients. Muscle biopsy findings showed central nuclei and variations in fiber size. One of the patients showed ragged red fibers in muscles of the biceps brachii. To our knowledge, this is the first report of typical winged scapula in DM1.

Pathophysiologic evaluation of MELAS strokes by serially quantified MRS and CASL perfusion images.

PURPOSE: To clarify the roles of serial MR spectroscopy (MRS) and continuous arterial spin labeling (CASL) perfusion images for evaluating cerebral lesions in patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). MATERIALS AND METHODS: Two cases of MELAS followed up serially using MRS and CASL images in addition to routine MR imaging were enrolled. RESULTS: Newly appeared lesions assessed by MRS revealed increased lactate doublets which correlated well with CSF lactate level, and these showed a decreasing trend after treatment, although conventional T2 weighted images revealed hyper-intensity in both phases. Spectra from normally appearing white matter depicted slight lactate peaks during clinical exacerbation periods with marked elevation of CSF lactate and showed a decreasing NAA concentration during the prolonged course. In CASL images, acute lesions of the disease were clearly visible as hyper-perfusion foci, and chronic lesions were demonstrated as hypo- or iso-perfusion regions. CONCLUSION: The detection of lactate peaks in the MR spectrum from normally appearing white matter may be considered as systemic lactic acidosis or an exacerbation of MELAS, and active lesions can be distinguished from chronic inactive lesions by the increase of lactate peaks in MRS or the state of hyper-perfusion in CASL images.

Tissue characterization of glioma by proton magnetic resonance spectroscopy and perfusion-weighted magnetic resonance imaging: glioma grading and histological correlation.

BACKGROUND AND PURPOSE: Our intent was to clarify the usefulness of proton magnetic resonance spectroscopy (MRS) and perfusion-weighted magnetic resonance imaging (PW-MRI) in the grading of glioma. METHODS: Twenty-three consecutive patients with gliomas were investigated by both proton MRS and PW-MRI. For quantitative analysis, the metabolite data of the gliomas were estimated using the LCModel software. Receiver operating characteristic (ROC) curve analyses were also performed to assess which metabolite parameter was optimal for discrimination of glioma grade. From the PW-MRI data, the value of blood volume was measured on the parametric map corresponding to the location of MRS analysis. We then compared tumor blood volume with the amount of choline (Cho). RESULTS: The mean Cho/creatine (Cre) ratio was useful to discriminate between Grades II and III, and the mean lactate (Lac)/Cre ratio was found to be significantly different between Grades III and IV. ROC curve analysis showed that measurements involving Cho were superior indices for grading glioma compared with blood volume information. Furthermore, the correlation between tumor blood volume and the amount of choline was statistically significant. CONCLUSION: MRS may provide valuable information for glioma grading.

18F-FDG PET of common enhancing malignant brain tumors.

OBJECTIVE: The purpose of our study was to determine whether (18)F-FDG PET can be used to differentiate among common enhancing brain tumors such as lymphoma, high-grade glioma, and metastatic brain tumor. MATERIALS AND METHODS: We evaluated 34 patients with an enhancing brain tumor on MRI, including seven lymphomas, nine high-grade gliomas, and 18 metastatic tumors. All patients also underwent FDG PET. For PET image analysis, regions of interest were placed over the tumor (T), contralateral cortex (C), and white matter (WM). Average and maximum pixel values were determined at each site. On the basis of these measurements, average and maximum standard uptake values (SUV(avg) and SUV(max)) were calculated, along with activity ratios (T/C(avg), T/WM(avg), T/WM(max), and T/C(max)), and comparisons among lesions were then made. RESULTS: All parameters were significantly higher for lymphoma than for other tumors (p < 0.01). High-grade gliomas showed significantly higher SUV(avg) and SUV(max) than metastatic tumors (p < 0.05). Other parameters did not differ between lesion types. SUV(max) was the most accurate parameter for distinguishing lymphomas. Using an SUV(max) of 15.0 as a cutoff for diagnosing CNS lymphoma, only one high-grade glioma was found as a false-positive (SUV(max), 18.8). CONCLUSION: FDG PET may be useful for differentiating common enhancing malignant brain tumors, particularly lymphoma versus high-grade glioma and metastatic tumor. FDG PET can provide useful information for distinguishing between lymphoma and other malignant enhancing brain tumors and is recommended when differential diagnoses are difficult to narrow using MRI alone.

Rare causes of hematuria associated with various vascular diseases involving the upper urinary tract.

Hematuria is a commonly encountered symptom of a wide spectrum of diseases, including calculi, tumors, and vascular abnormalities. In rare cases, hematuria is caused by life-threatening vascular diseases. When hematuria is encountered, physicians sometimes fail to include vascular diseases in the differential diagnosis because of their rare association with hematuria. Likewise, radiologists often fail to do so because of the low frequency of occurrence of these diseases. Multidetector computed tomography performed with the bolus injection technique should be the first-line diagnostic test when vascular disease is suspected. Radiologists should be familiar with the various imaging findings of hematuria caused by vascular disease. They should also be familiar with the management options (including endovascular techniques) for hematuria caused by vascular disease, since in some cases affected patients can be treated with interventional procedures.

Apparent diffusion coefficient in pancreatic cancer: characterization and histopathological correlations.

PURPOSE: To clarify the components primarily responsible for diffusion abnormalities in pancreatic cancerous tissue. MATERIALS AND METHODS: Subjects comprised 10 patients with surgically confirmed pancreatic cancer. Diffusion-weighted (DW) echo-planar imaging (b value = 0, 500 s/mm(2)) was employed to calculate the apparent diffusion coefficient (ADC). ADC values of cancer and noncancerous tissue were calculated. Furthermore, ADC values of the cancer were compared with histopathological results. RESULTS: The mean (+/-standard deviation) ADC value was significantly lower for tumor (1.27 +/- 0.52 x 10(-3) mm(2)/s) than for noncancerous tissue (1.90 +/- 0.41 x 10(-3) mm(2)/s, P < 0.05). Histopathological examination showed similar proportions of fibrotic area, cellular component, necrosis, and mucin in each case. Regarding the density of fibrosis in cancer, three cases were classified in the loose fibrosis group and the remaining seven cases were classified in the dense fibrosis group. The mean ADC value was significantly higher in the loose fibrosis group (1.88 +/- 0.39 x 10(-3) mm(2)/s) than in the dense fibrosis group (1.01 +/- 0.29 x 10(-3) mm(2)/s, P < 0.05). In quantitative analysis, ADC correlated well with the proportion of collagenous fibers (r = -0.87, P < 0.05). CONCLUSION: Collagenous fibers may be responsible for diffusion abnormalities in pancreatic cancer.

Rate of liver volume increase: can it predict recipient prognosis after left lobe transplantation from living related donors?

PURPOSE: The purpose of this study was to determine whether liver volume increase can predict recipient outcome. MATERIALS AND METHODS: Size-matched left lobe transplantation was performed for 16 patients. Computed tomography was performed in Week 1 after transplantation. Rate of liver volume increase was compared between survivors and deceased subjects. RESULTS: Mean rate of liver volume increase was significantly higher for survivors than for fatalities. CONCLUSION: Rate of liver volume increase might be useful for predicting outcome of living donor liver transplantation.

Changes in T1 and T2 observed in brain magnetic resonance imaging with delivery of high concentrations of oxygen.

OBJECTIVE: The aim of this study was to clarify the relative contributions of the amount of oxygen in the blood, and vasoconstriction/dilation responsible for changes in T1 and T2 observed in brain during hyperoxia. METHODS: T1 and T2 values of the cerebral cortex and pituitary gland in mice were determined in room air. After room air was changed to either 100% oxygen (n = 8) or carbogen (n = 8), T1 and T2 values were again determined. Changes in each value with both gases were compared. RESULTS: In both challenges, T1 values of the cerebral cortex decreased, whereas significant T2 prolongation of the cerebral cortex and pituitary gland was demonstrated. However, both cortex and pituitary gland displayed similar responses in T1 and T2 values when exposed to 100% oxygen or carbogen. CONCLUSIONS: Reduction of T1 was introduced by the increased amount of dissolved oxygen in blood, and the increased fraction of oxyhemoglobin caused T2 prolongation. The contribution of vasoconstriction/dilation by carbogen to changes in T1 and T2 may be negligible.

Correction of inhomogeneous RF field using multiple SPGR signals for high-field spin-echo MRI.

PURPOSE: To propose a simple and useful method for correcting nonuniformity of high-field (3 Tesla) T(1)-weighted spin-echo (SE) images based on a B1 field map estimated from gradient recalled echo (GRE) signals. METHODS: To estimate B1 inhomogeneity, spoiled gradient recalled echo (SPGR) images were collected using a fixed repetition time of 70 ms, flip angles of 45 and 90 degrees, and echo times of 4.8 and 10.4 ms. Selection of flip angles was based on the observation that the relative intensity changes in SPGR signals were very similar among different tissues at larger flip angles than the Ernst angle. Accordingly, spatial irregularity that was observed on a signal ratio map of the SPGR images acquired with these 2 flip angles was ascribed to inhomogeneity of the B1 field. Dual echo time was used to eliminate T(2)(*) effects. The ratio map that was acquired was scaled to provide an intensity correction map for SE images. Both phantom and volunteer studies were performed using a 3T magnetic resonance scanner to validate the method. RESULTS: In the phantom study, the uniformity of the T(1)-weighted SE image improved by 23%. Images of human heads also showed practically sufficient improvement in the image uniformity. CONCLUSION: The present method improves the image uniformity of high-field T(1)-weighted SE images.

Assessment of the vascularity of uterine leiomyomas using double-echo dynamic perfusion-weighted MRI with the first-pass pharmacokinetic model: correlation with histopathology.

OBJECTIVES: To retrospectively evaluate the feasibility of perfusion-weighted MRI (PWI) in uterine leiomyomas. MATERIALS AND METHODS: : Eighteen uterine leiomyomas in 15 patients were evaluated. PWI was performed using a double-echo T2*-weighted spoiled gradient-recalled acquisition sequence, and the first-pass pharmacokinetic model was applied to calculate relative blood volume (rBV). Histopathologic analysis was performed to measure vascular area (VA). RESULTS: PWI was successful in 13 of 15 patients. On quantitative analysis, mean (+/-SD) rBV calculated from PWI was 0.17 +/- 0.13 (range, 0.06-0.55), whereas mean VA was 3.3% +/- 1.6% (range, 1.7-8.5%). A significant correlation was identified between rBV and VA (r = 0.87, P < 0.001). CONCLUSIONS: The rBV determined at PWI correlates with histologic vascular area in uterine leiomyomas.

Difficulties in the diagnosis of appendicitis: review of CT and US images.

To determine the reasons for missing a distended appendix, we discuss cases of acute appendicitis in which either or both computed tomography (CT) and/or ultrasonography (US) initially failed to detect distended appendix. In some cases, distended appendices that were undetected on US were easily detected by CT, and vice versa. Failure to detect a distended appendix does not always eliminate the possibility of acute appendicitis.

Utility of multi-detector CT for pre-operative diagnosis of internal hernia through a defect in the broad ligament (2007: 1b).

Internal hernia through a defect in the broad ligament is a rare cause of intestinal obstruction, and pre-operative diagnosis is generally difficult. Here, we report our experience in which multi-detector computed tomography (MDCT), which allows direct recognition of incarcerated small bowel, was useful in the pre-operative diagnosis of this hernia.

Imaging by multiple modalities of patients with a carotidynia syndrome.

The purpose of this article is to familiarize readers with the clinical syndrome of carotidynia. In the past, the International Headache Society (IHS) described idiopathic carotidynia as a diagnostic entity consisting of a self-limiting neck pain syndrome and tenderness over the carotid bifurcation without structural abnormality and then recently removed it from its classification. Although the clinical criteria of carotidynia in the former classification of the IHS included the absence of structural abnormality, several publications have demonstrated associated radiological findings and have described the usefulness of radiological investigations in diagnosing this syndrome. In this paper, we report four additional cases with a carotidynia clinical syndrome (according to the former classification) and the presence of abnormal soft tissue infiltration surrounding the symptomatic carotid artery as demonstrated by multiple imaging modalities, without any other underlying cause for the carotid pain syndrome. Our findings support the hypothesis that carotidynia could be a distinct disease entity, possibly caused by inflammation.

Double-echo perfusion-weighted MR imaging: basic concepts and application in brain tumors for the assessment of tumor blood volume and vascular permeability.

Perfusion-weighted magnetic resonance (MR) imaging using contrast agents plays a key role in characterizing tumors of the brain. We have shown that double-echo perfusion-weighted MR imaging (DEPWI) is potentially useful in assessing brain tumors. Quantitative indices, such as tumor blood volume, are obtained using DEPWI, which allows correction of underestimation of tumor blood volume due to leakage of contrast agents from tumor vessels, in addition to simultaneous acquisition of tumor vessel permeability. This article describes basic concepts of DEPWI and demonstrates clinical applications in brain tumors.

Specific high-resolution computed tomography findings associated with sputum smear-positive pulmonary tuberculosis.

OBJECTIVES: This study aimed to evaluate whether high-resolution computed tomography (HRCT) could predict the results of a sputum smear in patients with active pulmonary tuberculosis. METHODS: Forty-eight patients with active pulmonary tuberculosis were divided into 2 groups: sputum smear-positive (n = 25) and -negative (n = 23). The HRCT findings were retrospectively reviewed, focusing on the presence or absence of features previously reported to indicate active pulmonary tuberculosis, including ground-glass opacity, cavitation, centrilobular opacity, and air space consolidation. RESULTS: Although air space consolidation was the least common feature overall, it occurred significantly more frequently in the smear-positive group than in the smear-negative group. This feature also had the highest specificity and positive predictive value. Cavitation and ground-glass opacity also occurred significantly more frequently in the smear-positive group. The frequency of centrilobular opacity did not differ between the 2 groups. CONCLUSIONS: The present study suggested that the HRCT findings of air space consolidation, cavitation, and ground-glass opacity are significantly associated with smear-positive pulmonary tuberculosis.

Solitary plasmacytoma of the sacrum. Radiologic findings of three cases.

We report the radiologic findings from three cases of solitary plasmacytoma (SP) of the sacrum. Common findings included lytic changes on computed tomography (CT) and relatively low signal intensity on T2-weighted magnetic resonance (MR) images, with intense enhancement after contrast administration. All cases showed infiltrating and slightly expansive growth, but the sacral structure was generally maintained. These radiologic findings may be of utility when generating a differential diagnosis of a solitary sacral tumor.