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Isolated tuberculous liver parenchymal and subcapsular abscesses are unusual,^but an abdominal wall abscess secondary to a tubercular liver abscess is extremely rare. To our knowledge, there is only one reported case of an abdominal wall abscess occurring secondary to a subcapsular liver abscess. We report the first documented case of direct invasion of the abdominal wall from an isolated tuberculous liver parenchymal abscess, diagnosed by imaging, surgical, and pathological findings. Although ultrasonography and computed tomography showed nonspecific hypoechoic and hypodense findings with peripheral contrast enhancement, T2-weighted magnetic resonance imaging (MRI) revealed a heterogeneous mass with characteristic hypointensity, suggesting the presence of free radicals produced by macrophages during active phagocytosis in tuberculosis. Although our case is extremely unusual, when hypointensity on T2-weighted MRI is seen, the possibility of tuberculosis should be considered and the results of polymerase chain reaction, culture, and histopathological diagnosis must be taken into account to avoid needless invasive surgery.

Multidetector row computed tomography (MDCT) creates massive amounts of data, which can overload a picture archiving and communication system (PACS). To solve this problem, we designed a new data storage and image interpretation system in an existing PACS. Two MDCT image datasets, a thick- and a thin-section dataset, and a single-detector CT thick-section dataset were reconstructed. The thin-section dataset was archived in existing PACS disk space reserved for temporary storage, and the system overwrote the source data to preserve available disk space. The thick-section datasets were archived permanently. Multiplanar reformation (MPR) images were reconstructed from the stored thin-section datasets on the PACS workstation. In regular interpretations by eight radiologists during the same week, the volume of images and the times taken for interpretation of thick-section images with (246 CT examinations) or without (170 CT examinations) thin-section images were recorded, and the diagnostic usefulness of the thin-section images was evaluated. Thin-section datasets and MPR images were used in 79% and 18% of cases, respectively. The radiologists' assessments of this system were useful, though the volume of images and times taken to archive, retrieve, and interpret thick-section images together with thin-section images were significantly greater than the times taken without thin-section images. The limitations were compensated for by the usefulness of thin-section images. This data storage and image interpretation system improves the storage and availability of the thin-section datasets of MDCT and can prevent overloading problems in an existing PACS for the moment.

Primary pleural synovial sarcoma is a rare disease with poor outcomes. Although hyperthermia therapy as part of a combined treatment regimen can offer improved local tumor control, only two reports of hyperthermia therapy for synovial sarcoma have appeared in the literature, and these sarcomas were not of pleuropulmonary origin. This report of an advanced inoperable primary pleural synovial sarcoma is the first to address the use of hyperthermia therapy in combination with chemoradiotherapy for this disease, together with radiological assessment following that therapy. Computed tomography performed after thermoradiation showed a decrease in tumor size and a characteristic unenhanced low-density area in the tumor suggesting that tumor necrosis resulted from the therapy. These image findings were helpful in assessing the tumor response to thermoradiation. We believe that hyperthermia therapy combined with chemoradiotherapy should be regarded as an option for advanced primary pleural synovial sarcoma. This would give computed tomography important role in evaluating this approach.

The patient was a 63-year-old woman with a chief complaint of blood-stained sputum. A tumor of the inferior vena cava was found on chest computed tomography (CT) and identified as a primary tumor based on multidetector CT and contrast-enhanced MR angiography. An intrapelvic tumor was also discovered. On autopsy, the two tumors were diagnosed as leiomyosarcoma and ovarian fibroma, respectively.

We report the case of a 31-year-old woman who suffered lipiduria after selective transcatheter arterial embolization for renal angiomyolipoma (AML). Computed tomography confirmed cystic liquefactive necrosis with fat-fluid level in AML. Although the process by which AML fat tissue excretion occurs is not clear, we speculated that the infarcted AML was connected to the urinary collection duct system and subsequently its adipose component was excreted into the urine.

The characteristics of jejunal ectopic pancreas in dynamic gadolinium-enhanced magnetic resonance imaging are described in a 40-year-old man with bowel obstruction. The pre-contrast signal intensity and post-contrast enhancement pattern of ectopic pancreas are the same as those of the pancreas.

To solve the problems of image displays in filmless radiology conferences for the purpose of teaching, we made an experimental design of a conference system with dual 50-in. plasma monitors for displaying larger images and a shared folder containing shortcuts to images for quick display during conferences on the desktop of each client computer in a picture archival and communication system. The image quality of the monitors was evaluated using the TG18-QC test pattern. The display time of images was measured in 20 cases when the shared folder was used and when it was not. Monitor screen size and image quality, operability, display time of images, and overall impression given by the system were evaluated subjectively by five radiologists. Although the image quality of the monitor was not as high as that of the high-resolution monitors used for diagnostic radiology, its performance was good enough for teaching. The average display time using the shared folder (2.6 +/- 0.39 s) was significantly shorter than without it (16.9 +/- 5.04 s; p = 2.85 x 10(-6)). Despite the need for certain improvements in monitor size and in the operability of the system, the radiologists considered the system suitable for radiology teaching conferences. We believe that this system is useful for institutions that intend to introduce a filmless system for filmless radiology teaching conferences.

Although accurate information on thoracolumbar bone structure is essential when computed tomography (CT) images are examined, there is no automated method of labeling all the vertebrae and ribs on a CT scan. We are developing a computer-aided diagnosis system that labels ribs and thoracolumbar vertebrae automatically and have evaluated its accuracy. A candidate bone was extracted from the CT image volume data by pixel thresholding and connectivity analysis. All non-bony anatomical structures were removed using a linear discriminate of distribution of CT values and anatomical characteristics. The vertebrae were separated from the ribs on the basis of their distances from the centers of the vertebral bodies. Finally, the thoracic cage and lumbar vertebrae were extracted, and each vertebra was labeled with its own anatomical number by histogram analysis along the craniocaudal midline. The ribs were labeled in a similar manner, based on location data. Twenty-three cases were used for accuracy comparison between our method and the radiologist's. The automated labeling of the thoracolumbar vertebrae was concordant with the judgments of the radiologist in all cases, and all but the first and second ribs were labeled correctly. These two ribs were frequently misidentified, presumably because of pericostal anatomical clutter or high densities of contrast material in the injected veins. We are confident that this system can contribute usefully as part of a picture archiving and communication system workstation, though further technical improvement is required for identification of the upper ribs.

No adverse allergic reactions to iodine-131-metaiodobenzylguanidine ((131)I MIBG) at a diagnostic dose have been reported in the English literature. This report of a skin eruption in a 35-year-old man after an intravenous injection of (131)I MIBG strongly suggests an adverse allergic reaction, and is the first to address such a side effect of (131)I MIBG at a diagnostic dose. Erythematous maculopapular eruptions, some of which were contiguous, were seen in a symmetric disposition on the patient's chest walls, elbows, neck and face 18 h after the (131)I MIBG injection. Antiallergic treatment resolved the lesions completely. There were no possible causes of the exanthema other than the (131)I MIBG injection. Urticaria related to the (131)I MIBG injection and caused by type I allergic reaction was suspected, and these findings point to the possible risk of a hitherto unreported allergic skin reaction to (131)I MIBG. We would like to draw the attention of nuclear physicians to this possible drawback of (131)I MIBG.

A 74-year-old man presented with left ventricular failure and nonsustained ventricular tachycardia. Coronary angiography revealed normal coronary arteries; left ventriculography showed hypokinesis of the lateral wall segment. The ejection fraction was 54%. Cine-magnetic resonance imaging showed a double-layered appearance on four-chamber view and marked trabeculations as well as intratrabecular recesses in the inferolateral segments on short-axis view, findings consistent with isolated noncompaction of the ventricular myocardium (INVM). Contrast-enhanced imaging revealed hypoperfusion and delayed enhancement of the endomyocardium in the inferolateral segments. Subendomyocardial perfusion abnormality and necrosis may constitute the diagnostic criteria of INVM.

Ectopic thyroid tissue is an uncommon congenital aberration that is seldom present at two different sites simultaneously. The patient was a 32-year-old woman with dual ectopic thyroid accompanied by positive antithyroid antibodies. The simultaneous occurrence of dual ectopic thyroid and positive antithyroid antibodies has been documented in only two cases: the case discussed here and one previous case. The cervical ectopic thyroid was followed up by ultrasound, which showed an increase in the size of the lesion and an internal echo texture that became slightly heterogeneous after the patient had her second child. We speculated that these changes resulted from the changes in hormone demand brought on by pregnancy and parturition.

Isolated noncompaction of the ventricular myocardium (INVM) is an unclassified cardiomyopathy and is thought to be due to arrest of myocardial morphogenesis. Although right ventricular involvement is not uncommon, the correct diagnosis is often difficult by echocardiography. In this report, we describe a patient with INVM in whom magnetic resonance imaging was useful to detect right ventricular morphological and functional abnormalities.

A 68-year-old woman was admitted to our hospital because of left ventricular failure. Myocardial perfusion single-photon emission computed tomography demonstrated a non-reversible perfusion defect in the anterolateral left ventricular segments and reduced ejection fraction, findings consisted with ischemic cardiomyopathy accompanied by lateral wall infarction. Coronary angiogram was normal, but the left ventriculogram showed prominent trabeculations in the apical and anterolateral segments. The left ventricular ejection fraction was 28%. Cine magnetic resonance imaging demonstrated prominent trabeculations and deep intertrabecular recesses, findings consistent with noncompaction of the ventricular myocardium. Myocardial hypoperfusion or necrosis in the noncompacted myocardium may be the cause of myocardial damage and possibly the basis of left ventricular failure.

Laryngeal papillomatosis is a rare benign disease seen in children and young adults. The spread of laryngeal papillomas throughout the respiratory tract occurs rarely; and involvement of the distal bronchi, bronchioles, and lung parenchyma is very rare. We report a case of pulmonary spread of laryngeal papillomatosis in a 34-year-old man, focusing on the radiological evidence. Chest radiographs showed pulmonary nodules, but computed tomography scans more clearly demonstrated multiple small nodules showing cavitations and distributed centrilobularly. Pulmonary nodules and cavitations progressed gradually through the 6-year follow-up. The combination of clinical and characteristic radiological features suggests a diagnosis of pulmonary spread of laryngeal papillomatosis.

Recent pathological and clinical observations support the notion that coronary artery plaque disruption and subsequent thrombosis is the primary cause of acute coronary syndrome (ACS) including acute myocardial infarction and unstable angina. Therefore, detection and characterization of coronary artery plaques are of utmost importance in the management of patients with suspected coronary artery disease. Histologic and clinical observations using intravascular ultrasound have suggested that vulnerable, rupture-prone plaques are characterized by the presence of large lipid cores, thin fibrous caps and positive coronary artery remodeling. In this review, we describe the efficacy of multislice computed tomography (MSCT) to characterize vulnerable plaques, especially in patients with suspected ACS. In addition, the efficacy of coronary magnetic resonance imaging is discussed.

Anomalous origin of the right coronary artery (RCA) is a rare condition, but may cause myocardial ischemia and sudden death. Multislice computed tomography, which allows three-dimensional visualization of the coronary artery with high spatial resolution, may be the most promising imaging modality for diagnosing this anomaly. We describe a patient with anomalous origin of the RCA arising from the left sinus of Valsalva. Volume rendering, and axial and curved multiplanar images showed stenosis in the proximal portion of the RCA that coursed between the aorta and the pulmonary artery, and an acute angled take-off of the RCA from the aorta. Three-dimensional virtual angioscopic images showed a hypoplastic RCA orifice and luminal narrowing in the proximal portion of the RCA. Multislice computed tomography was thought to be useful for detecting anomalous origin of the RCA and for evaluating possible causes of myocardial ischemia.

Background: The diagnosis of acute coronary syndrome (ACS), especially non-ST-elevation myocardial infarction and unstable angina in the emergency department (ED) still remains a challenge. Multislice computed tomography (MSCT) allows assessment of not only coronary artery stenoses and occlusions, but also assessment of coronary artery plaques and myocardial perfusion status., Methods and Results: MSCT was performed in 31 patients who were admitted to the ED because of chest pain persisting at least 30 min and non-diagnostic ECG changes and normal serum enzyme concentrations. Using MSCT, ACS was defined by coronary artery stenosis > or = 75% accompanied by computed tomography (CT)-low-density plaques, and/or by the presence of myocardial perfusion defects. ACS was confirmed by coronary stenosis > or = 75% by coronary angiography and/or subsequent elevation of troponin I concentration. In total, 22 patients were diagnosed as having ACS. MSCT detected stenoses with CT-low-density plaques in 21 and non-transmural myocardial perfusion defect in 3 patients. There was 1 false-positive and 1 false-negative result. The sensitivity and specificity of MSCT to identify ACS was 95.5% and 88.9%, respectively., Conclusion: MSCT provides diagnostic operating characteristics suitable for triage of patients with ACS in the ED.

Background: Anomalous origins of the coronary artery are rare, but may cause myocardial ischemia and sudden death. Thus, their reliable identification is crucial for any imaging method that attempts coronary artery visualization and of those available multislice computed tomography (MSCT), which provides excellent spatial resolution, may be the most promising., Methods and Results: In consecutive 1,153 patients, MSCT identified 5 patients (0.43 %) with an anomalous origin of the coronary artery. The left circumflex artery (LCX) originated from the right sinus of Valsalva in 1 patient, and the right coronary artery originated from the left sinus of Valsalva and coursed between the aortic root and the pulmonary artery in 3 patients. In 1 patient, MSCT identified the absence of the LCX and high-grade atherosclerotic stenosis in the right coronary artery., Conclusion: MSCT can detect the anomalous origin and course of the coronary artery in relation to the great vessels. It is also useful for identifying atherosclerotic coronary artery disease superimposed on the anomalous vascular system.

The high spatial resolution of multislice computed tomography (MSCT) permits direct visualization of the coronary artery system. In this report, we describe coronary artery abnormalities in a young adult with Kawasaki disease. MSCT detected a giant coronary artery aneurysm, coronary artery stenosis in the first diagonal artery, and a multi-layered structure in the right coronary artery and the left circumflex artery. These findings corresponded well to those obtained by coronary angiography. MSCT has the potential to be the standard diagnostic tool for the follow-up evaluation of coronary artery disease in adolescents and young adults with Kawasaki disease.

Multislice spiral computed tomography (MSCT) permits direct visualization of not only coronary artery stenosis but also atherosclerotic plaques in patients with coronary artery disease. In this report, we describe a patient with stable angina in whom the regression of the plaque was documented by serial MSCT examinations. In the patient, a 46-year-old man with stable angina, MSCT revealed a stenotic lesion at the proximal portion of the left anterior descending artery. Axial, curved multiplanar reconstruction and cross-sectional images consistently depicted a protruding computed tomography low-signal mass suggesting an atherosclerotic plaque. Intracoronary ultrasound (ICUS) also documented an eccentric soft plaque with an echo-lucent mass suggesting a lipid core. Lipid-lowering therapy with pravastatin was started. Follow-up MSCT performed 7 months later documented an increase in the luminal area while the external vessel area remained unchanged. The regression of the plaque was also confirmed by a follow-up ICUS study. MSCT was thought to be feasible for serial evaluation of the plaque size and texture.

The present study was designed to investigate the accuracy of multislice spiral computed tomography (MSCT) in detecting coronary artery disease, compared with coronary angiography (CAG), using a new retrospectively ECG-gated reconstruction method that reduced cardiac motion artifact. The study group comprised 54 consecutive patients undergoing MSCT and CAG. MSCT was performed using a SOMATOM Volume Zoom (4-detector-row, Siemens, Germany) with slice thickness 1.0 mm, pitch 1.5 (table feed: 1.5 mm per rotation) and gantry rotation time 500 ms. Metoprolol (20-60 mg) was administered orally prior to MSCT imaging. ECG-gated image reconstruction was performed with the reconstruction window (250 ms) positioned immediately before atrial contraction in order to reduce the cardiac motion artifact caused by the abrupt diastolic ventricular movement occurring during the rapid filling and atrial contraction periods. Following inspection of the volume rendering images, multiplanar reconstruction images and axial images of the left main coronary artery (LMCA), left anterior descending artery (LAD), left circumflex artery (LCx) and right coronary artery (RCA) were obtained and evaluated for luminal narrowing. The results were compared with those obtained by CAG. Of 216 coronary arteries, 206 (95.4%) were assessable; 10 arteries were excluded from the analysis because of severe calcification (n=4), stents (n=3) or insufficient contrast enhancement (n=3). The sensitivity to detect coronary stenoses >or=50% was 93.5% and the specificity to define luminal narrowing <50% was 97.2%. The positive predictive value and the negative predictive value were 93.5% and 97.2%, respectively. The sensitivity was still satisfactory (80.6%) even when non-assessable arteries were included in the analysis. The new retrospectively ECG-gated reconstruction method for MSCT has excellent diagnostic accuracy in detecting significant coronary artery stenoses.

In patients with Kawasaki disease (KD), serial evaluation of coronary artery aneurysms (CAAs) and luminal narrowing is essential for risk stratification and therapeutic management. Therefore, non-invasive assessment of the status of the coronary artery is of utmost importance in patient management. Multislice spiral computed tomography (MSCT) permits non-invasive visualization of the entire coronary artery system and was used in the evaluation of 4 patients with KD. CAAs and high-grade coronary artery stenoses were detected by MSCT and corroborated the findings of coronary angiograms performed within the previous 2 years. MSCT has the potential to be the standard diagnostic tool in adolescents with KD.

Although the excellent spatial resolution of multislice spiral computed tomography (MSCT) enables the coronary arteries to be visualized, its limited temporal resolution results in poor image reproducibility because of cardiac motion artifact (CMA) and hence limits its widespread clinical use. A novel retrospectively ECG-gated reconstruction method has been developed to minimize CMA. In 88 consecutive patients, the scan data were reconstructed using 2 retrospectively ECG-gated reconstruction methods. Method 1: the end of the reconstruction window (250 ms) was positioned at the peak of the P wave on ECG, which corresponded to the end of the slow filling phase during diastole immediately before atrial contraction. Method 2 (conventional method): relative retrospective gating with 50% referred to the R-R interval was performed so that the beginning of the reconstruction window (250 ms) was positioned at the halfway point between the R-R intervals of the heart cycle. The quality of the coronary artery images was evaluated according to the presence or absence of CMA. The assessment was applied to the left main coronary artery (LMCA), the left anterior descending artery (LAD, segments #6, #7 and #8), the left circumflex artery (LCx, segments #11 and #13) and the right coronary artery (RCA, segments #1, #2 and #3). The first diagonal artery (#9-1), the obtuse marginal artery (#12-1), the posterior descending artery (#4-PD), the atrioventricular node branch (#4-AV) and the first right ventricular branch (RV) were also evaluated. Of the 88 patients, 85 were eligible for image evaluation. Method 1 allowed visualization of the major coronary arteries without CMA in the majority of patients. The LCA system (segments #5-7, #11 and #13) and the proximal portion of the RCA were visualized in more than 94% of patients. Artifact-free visualization of the distal portion of the LAD (segment #8) and RCA (#4PD and #4AV), and side branches (#9-1, #12-1 and RV) was also achieved in more than 80% of patients. On the other hand, CMA occurred frequently on images obtained by Method 2. The LCx and RCA systems were the most affected by CMA, revealing only 41% artifact-free visualization of the segment #13, 39% of #1, 15% of #2 and 32% of #3. Thus, Method 1, which avoids the ventricular motion occurring during the rapid filling and atrial contraction phases, gives superior image quality over the conventional ECG-gated reconstruction method.

Purpose: We report a patient who suffered from prolonged loss of taste acuity after partial oral cavity irradiation., Methods: The electric taste threshold (ETT) of each point in the oral cavity was measured with an electric gustometer to evaluate quantitative local taste acuity. A subjective total taste acuity (STTA) scale was used to evaluate subjective total taste acuity., Case: A 61-year-old male patient with right buccal mucosal cancer underwent radiation therapy more than 11 years ago, and has suffered from loss of taste acuity since then. He received electron beam irradiation to part of the oral cavity and right upper neck, mainly the right buccal mucosa near the retromolar trigone and a metastatic right submandibular node. He did not receive irradiation to the anterior portion of the tongue or left side of the posterior portion of the tongue. His ETT scores for each point were equal to or greater than 26, and his STTA score was grade 3., Conclusion: The present case implies that radiation damage to part of the oral cavity can cause the loss of subjective total taste acuity.