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We report an ectopic mediastinal parathyroid adenoma in a patient with chronic kidney disease who presented with refractory hypercalcemia. Technetium-99m-sestamibi scintigraphy is a valuable imaging technique for the detection of an ectopic parathyroid adenoma in the mediastinum. The combination of intense contrast enhancement and the identification of a polar vessel on a computed tomography scan will ensure that a radiologist can differentiate a parathyroid adenoma from other pathologies in the mediastinum. By virtue of the advancement of imaging modalities, localization of an ectopic mediastinal parathyroid adenoma prior to surgery is possible and unnecessary neck exploration is avoidable.

To evaluate the feasibility of low-concentration contrast medium (CM) for vascular enhancement, image quality, and radiation dose on computed tomography aortography (CTA) using a combined low-tube-voltage and iterative reconstruction (IR) technique. Ninety subjects underwent dual-source CT (DSCT) operating in dual-source, high-pitch mode. DSCT scans were performed using both high-concentration CM (Group A, n = 50; Iomeprol 400) and low-concentration CM (Group B, n = 40; Iodixanol 270). Group A was scanned using a reference tube potential of 120 kVp and 120 reference mAs under automatic exposure control with IR. Group B was scanned using low-tube-voltage (80 or 100 kVp if body mass index ≥25 kg/m(2)) at a fixed current of 150 mAs, along with IR. Images of the two groups were compared regarding attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), iodine load, and radiation dose in various locations of the CTA. In comparison between Group A and Group B, the average mean attenuation (454.73 ± 86.66 vs. 515.96 ± 101.55 HU), SNR (25.28 ± 4.34 vs. 31.29 ± 4.58), and CNR (21.83 ± 4.20 vs. 27.55 ± 4.81) on CTA in Group B showed significantly greater values and significantly lower image noise values (18.76 ± 2.19 vs. 17.48 ± 3.34) than those in Group A (all Ps

Pulmonary embolism (PE) is usually associated with deep vein thrombosis (DVT) in the lower extremities. However, foreign bodies in the pulmonary arteries can rarely cause PE without evidence of DVT. In this report, we present a case of diffuse PE associated with a migrated thread-like structure of the right-side heart and pulmonary arteries in a 70 year-old woman. The patient underwent several episodes of percutaneous vertebroplasty (PV) to treat compression fractures. The thread-like foreign bodies were identified as the bone cement injected during the previous PV procedures. We present this case study to emphasise that clinicians should consider the possibility of PE as a late complication, especially those with a history of PV.

Cardiac lipoma is a rare benign primary cardiac tumor and is usually asymptomatic (1). It is usually discovered incidentally but can be related to hemodynamic obstruction depending on its location (2). There have been several reports regarding cardiac lipoma, including its clinical presentation and characteristic findings on computed tomography (CT) (2, 3). However, few cases documented the characteristic CT findings of solitary or multiple cardiac lipomas in the patient with tuberous sclerosis; and to our knowledge, no cases of biventricular lipoma or lipomatous hypertrophy with multifocal fat in a non-tuberous sclerosis patient have ever been reported (4). Therefore, we here report a case of right ventricular (RV) lipomatous mass and multifocal fat infiltration in both ventricles, which were incidentally detected in a young woman showing an abnormal electrocardiogram (ECG) finding. CASE REPORT

To determine the improvement of emphysema quantification with density correction and to determine the optimal site to use for air density correction on volumetric computed tomography (CT).Seventy-eight CT scans of COPD patients (GOLD II-IV, smoking history 39.2±25.3 pack-years) were obtained from several single-vendor 16-MDCT scanners. After density measurement of aorta, tracheal- and external air, volumetric CT density correction was conducted (two reference values: air, -1,000 HU/blood, +50 HU). Using in-house software, emphysema index (EI) and mean lung density (MLD) were calculated. Differences in air densities, MLD and EI prior to and after density correction were evaluated (paired t-test). Correlation between those parameters and FEV1 and FEV1/FVC were compared (age- and sex adjusted partial correlation analysis).Measured densities (HU) of tracheal- and external air differed significantly (-990 ± 14, -1016 ± 9, P0.001). MLD and EI on original CT data, after density correction using tracheal- and external air also differed significantly (MLD: -874.9 ± 27.6 vs. -882.3 ± 24.9 vs. -860.5 ± 26.6; EI: 16.8 ± 13.4 vs. 21.1 ± 14.5 vs. 9.7 ± 10.5, respectively, P0.001). The correlation coefficients between CT quantification indices and FEV1, and FEV1/FVC increased after density correction. The tracheal air correction showed better results than the external air correction.Density correction of volumetric CT data can improve correlations of emphysema quantification and PFT.

Although imaging of patient with COPD in not recommended in clinical practice, many researches and drug trial include imaging studies in evaluation of COPD. In particular, thin-section volumetric CT covering the whole lung with following quantitative assessment has been accepted one of the essential components of studies. This chapter encompasses the whole aspect of CT in COPD, including basic CT physics, radiation dose consideration, diagnosis and visual assessment of COPD, fundamentals of quantitative assessment of emphysema, airway wall thickening, and air trapping and its clinical values. Assessment of other components of COPD includes chest wall changes, vascular changes, osteoporosis, and so on. In addition, new emerging imaging methods such as MRI, dual-energy CT, PET, and optical imaging to evaluate not only morphologic but also functional aspects of lung in COPD will be introduced. Functional imaging includes direct visualization of ventilation, perfusion, chest wall motion, and inflammation. The promising results of early studies will be introduced, highlighting the potential of imaging approach for the future studies.

Sudden cardiac death (SCD) is defined as the unexpected natural death from a cardiac cause within an hour of the onset of symptoms in the absence of any other cause. Although such a rapid course of death is mainly attributed to a cardiac arrhythmia, identification of structural heart disease by cardiovascular computed tomography (CCT) and cardiovascular magnetic resonance (CMR) imaging is important to predict the long-term risk of SCD. In adults, SCD most commonly results from coronary artery diseases, coronary artery anomalies, inherited cardiomyopathies, valvular heart diseases, myocarditis, and aortic dissection with coronary artery involvement or acute aortic regurgitation. This review describes the CCT and CMR findings of structural heart diseases related to SCD, which are essential for radiologists to diagnose or predict.

The anomalous origin of the right coronary artery (RCA) is a rare condition. Most RCA anomalies are usually found incidentally, but these findings have clinical significance because many patients, particularly young ones, present with sudden death, myocardial ischemia and syncope without other symptoms. We describe a case of a 39-year-old male patient that presented with effort chest pain and was diagnosed with anomalous RCA that originated from the ascending aorta with prior history of repairing ruptured sinus valsalva and ventricular septal defect. The anomalous origin of RCA was identified by multidetector computed tomography (MDCT). Successful percutaneous coronary intervention was performed guided by MDCT coronary images and intravascular ultrasound.

Inadvertent left internal mammary artery (LIMA)-great cardiac vein (GCV) anastomosis is a rare complication of coronary artery bypass graft surgery. Patients with iatrogenic aortocoronary fistula (ACF) were usually treated surgical repair, percutaneous embolic occlusion with coil or balloon. We report a case of iatrogenic LIMA to GCV anastomosis successfully treated with coil embolization and protected left main coronary intervention through the percutaneous transfemoral approach.

Objective To ascertain the incidence of acute and chronic complications of aortic intramural hematoma (IMH) and to analyze the predictors of the development of each complication. Materials and methods This retrospective study includes 107 consecutive patients diagnosed with aortic IMH by means of computed tomography (CT) during the period from January 1998 to December 2003 and followed up with serial CT examinations (median follow-up period, 320 days). There were 36 patients with type A and 71 with type B IMH. Initial and follow-up CT scans were reviewed, with special attention given to the development of complications, such as increase in the thickness of IMH, clinical and hemodynamic evolution requiring urgent surgery, and development of aortic dissection and/or aneurysm. If each complication developed within 30 days after the initial episode, we classified it as an acute complication; the others were classified as chronic complications. The time interval between the initial and the subsequent CT examination showing each complication was recorded. To identify the predictors of each complication, we analyzed the demographic and CT findings with regard to the following factors: age, sex, maximum thickness of the hematoma, maximum aortic diameter on initial CT examination, ulcerlike projection (ULP) on initial and follow-up CT examinations, and the degree of atherosclerosis. The Cox proportional hazards regression model with stepwise multivariate analyses was used to determine the significant predictors of each complication. Results Sixteen patients had acute complications consisting of aortic dissection (n = 7), aortic aneurysm (n = 6), and acute clinical and hemodynamic evolution requiring operation (n = 3). Three additional patients with aortic dissection (n = 1) and aneurysm (n = 2) underwent emergency surgery. Twenty-three patients with chronic complications had aortic dissection (n = 3), and aortic aneurysm (n = 20). Cox proportional hazards regression model revealed that the maximal diameter of involved aorta is the only significant predictor of the development of acute complications (P = 0.006), whereas the age (P = 0.040), type A IMH (P = 0.015), presence of ULP (P = 0.015), and newly developed ULP as revealed on follow-up CT examination (P = 0.032) were significant predictors of the development of chronic complications. With regard to the aortic dissection in 10 patients (9.3%; type A/B ratio, 5:5; median time interval, 34 days), Cox proportional hazards regression model revealed that the maximal thickness of the hematoma is the only significant predictor (P = 0.018). Twenty-one saccular and 5 fusiform aneurysms (24.3%) developed, as revealed on follow-up CT examinations (median time interval, 180 days). The presence of ULP (P = 0.030), type A (P = 0.038) and the maximal thickness of the hematoma (P = 0.017) were significant predictors for the development of an aneurysm. Conclusions The maximum thickness of a hematoma on the initial CT is the significant factor predicting the development of aortic dissection and aortic aneurysm. Patients with type A IMH and ULP, as revealed by initial and short-term follow-up CT examinations, should be carefully followed up with subsequent CT examination to monitor the development of an aortic aneurysm, which is a relatively common chronic complication of IMH.

Intravascular lymphoma (IVL) is a rare type of extranodal non-Hodgkin's lymphoma. It is characterized by the proliferation of malignant lymphocytes within the lumen of small vessels and sparing of surrounding tissue (1,2,3,5). Pulmonary presentation of IVL is rare in Asian population and shows poor prognosis (4,5). It can be also a cause of unexplained interstitial lung disease. Because the prognosis is poor, the need of more intensive treatment should be considered. Two women, 56 years old (patient 1) and 59 years old (patient 2), commonly had a one month history of fever, weight loss, and upper respiratory symptoms. They did not show skin lesions and hepatosplenomegaly. Chest computed tomography (CT) scans also commonly showed ground-glass opacities and consolidations in both lungs (Fig. 1). In the bone marrow study, secondary hemophagocytosis (patient 1) and lymphoma involvement (patient 2) were observed, respectively. A positron emission tomography (PET) scan with 2 patients revealed diffuse increased glucose uptake in both of the lungs. These findings of CT scan and PET scan considered atypical bacterial or viral pneumonia, and acute hypersensitivity pneumonitis as possible diagnosis. An open lung biopsy for a confirmative diagnosis showed that CD20, CD79a, bcl-2, and MUM-1 were positive in the intravascular atypical cells (Fig. 1). Patient 1 was given best supportive care because of poor general condition due to delayed diagnosis. It was much delayed (2 months [patient 1], 1 month [patient 2], respectively) to diagnose finally from the initial hospital visit. On several reports, the prognosis of IVL is very poor, early introduction of systemic chemotherapy may be important to improve prognosis (4,6). The previous reports recommended an anthracycline-based chemotherapy regimen including CHOP. Rituximab is added in cases of B-cell lineage (2,3,6). Therefore we decided to use intensive chemotherapy for patient 2, who was given 3 cycles of R-hyper CVAD regimen. After 2 cycles of R-hyper CVAD, partial remission was observed. However, disease rapidly progressed and the patients eventually expired at three (patient 1) and four months (patient 2) after initial presentation, respectively. For early diagnosis of IVL with lung involvement, the early suspect based on symptoms, chest CT scan and PET scan are important because of no specific findings for IVL of lung involvement, and early aggressive diagnostic procedures (such as trans-bronchial biopsy, open lung biopsy) are required. Because the prognosis of IVL is poor, the more intensive treatment including front-line autologous transplantation should be explored. Here, we reported two cases of intravascular large B-cell lymphoma involving the lungs with their images and histopathology findings. Fig. 1 Findings of 56-year-old (A, B) and 59-year-old (C, D) women with pulmonary intravascular lymphoma. (A) Chest CT scan shows patchy GGOs and consolidations in both lungs, mainly located in the central portion. (B) Open lung biopsy specimen shows that many ...

Pulmonary metastases present a wide spectrum of radiological findings, some of which have been known to be useful for analogizing the possible origin or site of primary tumors. In the present report, we describe a unique case of pulmonary metastasis manifesting on chest computed tomography as multiple nodules with tortuous, serpentine, aneurysmal, dilated, inner intratumoral vessels. The metastasis originated from uterine sarcoma.

3Present address: Department of Radiology, Chungnam National University Hospital, Daejeon, Korea. eriaortic fibrosis, more commonly known as retroperitoneal fibrosis, is an uncommon disease that was first described in 1905 by Albaran [1] and further documented by Ormond in 1948 [2]. It is characterized by the progressive proliferation of connective tissue in the retroperitoneal space, specifically along the aorta [3, 4]. To our knowledge, ours is the first report in the English-language literature describing the CT and 18F-FDG PET findings of periaortic fibrosis with isolated involvement of the thoracic aorta. In this article, we describe the CT and FDG PET findings of an unusual case of periaortic fibrosis around the descending thoracic aorta. Intense FDG uptake on PET scans caused a false diagnosis of malignant tumor.

Immunoglobulin G4 (IgG4)-related periaortitis and periarteritis are rare systemic inflammatory and fibrosclerosing diseases, usually involving the aorta and its main branches. We report a pathologically confirmed case of IgG4-related periaortitis involving the thoracoabdominal aorta, which can be confused with intramural hematoma or periaortic lymphoma.

Swimming induced pulmonary alveolar hemorrhage is a rare disease. Here, we report a case of alveolar hemorrhage after snorkeling.

To provide a new detailed visual assessment scheme of computed tomography (CT) for chronic obstructive pulmonary disease (COPD) by using standard reference images and to compare this visual assessment method with quantitative CT and several physiologic parameters.This research was approved by the institutional review board of each institution. CT images of 200 participants in the COPDGene study were evaluated. Four thoracic radiologists performed independent, lobar analysis of volumetric CT images for type (centrilobular, panlobular, and mixed) and extent (on a six-point scale) of emphysema, the presence of bronchiectasis, airway wall thickening, and tracheal abnormalities. Standard images for each finding, generated by two radiologists, were used for reference. The extent of emphysema, airway wall thickening, and luminal area were quantified at the lobar level by using commercial software. Spearman rank test and simple and multiple regression analyses were performed to compare the results of visual assessment with physiologic and quantitative parameters.The type of emphysema, determined by four readers, showed good agreement (κ = 0.63). The extent of the emphysema in each lobe showed good agreement (mean weighted κ = 0.70) and correlated with findings at quantitative CT (r = 0.75), forced expiratory volume in 1 second (FEV(1)) (r = -0.68), FEV(1)/forced vital capacity (FVC) ratio (r = -0.74) (P.001). Agreement for airway wall thickening was fair (mean κ = 0.41), and the number of lobes with thickened bronchial walls correlated with FEV(1) (r = -0.60) and FEV(1)/FVC ratio (r = -0.60) (P.001).Visual assessment of emphysema and airways disease in individuals with COPD can provide reproducible, physiologically substantial information that may complement that provided by quantitative CT assessment.

To compare the measurement of global left-ventricular (LV) function parameters of 64-slice multidetector-row computed tomography (MDCT) between 20- and 10-reconstruction phases. Fifty five patients with suspected or known coronary artery disease underwent 64-slice MDCT. LV end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) were measured from MDCT data sets using threshold-based volume segmentation and reconstruction at every 5% (20 phases) and 10% (10 phases) step through the R-R interval. These global functional parameters were compared to those obtained via two-dimensional transthoracic echocardiography (2D-TTE), considering the reference standard. The required time for CT data analysis was checked. Agreement for parameters of LV global function was determined using Pearson's correlation coefficient (r) and Bland-Altman analysis. LV volumes (EDV(-5%) 87.5 ± 17.1 ml, EDV(-10%) 87.7 ± 16.3 ml; ESV(-5%) 32.4 ± 10.6 ml, ESV(-10%) 31.9 ± 9.9 ml; SV(-5%) 55.1 ± 10.5 ml, SV(-10%) 55.8 ± 9.9 ml; mean ± SD) and EF (EF(-5%) 63.4 ± 6.2%, EF(-10%) 63.9 ± 5.8%) did not differ significantly between the 20- and 10 phase reconstructions, and evidenced good to excellent correlation (r = 0.786-0.896, all P0.001) with the 2D-TTE results. The mean required time for CT data analysis in the 20- and 10 phase reconstructions were 15.5 ± 4.0 and 7.3 ± 2.5 min. Within MDCT, using 10-phase image reconstruction is sufficient to evaluate LV volumes and EF, and is also more time-effective than 20-phase reconstruction.

The incidence of aortic stent graft infection is with 0.2% to 0.7% low (1). However, there is an increasing need to be vigilant for the risk of stent graft infections as there are more patients treated using the endovascular technique. An early detection of graft infections and an adequate treatment during follow-up are also important to prevent serious complications. There have been several reports on stent graft infection with its characteristic clinical presentations and computed tomography (CT) findings (2-6). However, even with these characteristic CT findings, there have been few cases reported of abscess formation due to graft infection without characteristic CT findings, which could lead to either misdiagnosis or delayed diagnosis. We report a case of perigraft abscess formation that showed an increased size of aneurysmal sac without any apparent evidence of causative risk factors and was developed as a late complication 2 years after endovascular aortic repair (EVAR) for an abdominal aortic aneurysm (AAA).

Objective: To evaluate the impact of radiation dose and reconstruction algorithms on radiologists’ preferences, and whether an iterative reconstruction in image space (IRIS) can be used for dose reduction in chest CT. Materials and Methods: Standard dose chest CT (SDCT) in 50 patients and low dose chest CT (LDCT) in another 50 patients were performed, using a dual-source CT, with 120 kVp and same reference mAs (50 mAs for SDCT and 25 mAs for LDCT) employed to both tubes by modifying the dual-energy scan mode. Full-dose data were obtained by combining the data from both tubes and half-dose data were separated from one tube. These were reconstructed by using a filtered back projection (FBP) and IRIS: full-dose FBP (F-FBP); full-dose IRIS (F-IRIS); half-dose FBP (H-FBP) and half-dose IRIS (H-IRIS). Ten H-IRIS/F-IRIS, 10 H-FBP/H-IRIS, 40 F-FBP/F-IRIS and 40 F-FBP/H-IRIS pairs of each SDCT and LDCT were randomized. The preference for clinical usage was determined by two radiologists with a 5-point-scale system for the followings: noise, contrast, and sharpness of mediastinum and lung. Results: Radiologists preferred IRIS over FBP images in the same radiation dose for the evaluation of the lungs in both SDCT (p = 0.035) and LDCT (p < 0.001). When comparing between H-IRIS and F-IRIS, decreased radiation resulted in decreased preference. Observers preferred H-IRIS over F-FBP for the lungs in both SDCT and LDCT, even with reduced radiation dose by half in IRIS image (p < 0.05). Conclusion: Radiologists’ preference may be influenced by both radiation dose and reconstruction algorithm. According to our preliminary results, dose reduction at 50% with IRIS may be feasible for lung parenchymal evaluation. Index terms: Iterative reconstruction in image space; Chest CT; Radiation dose reduction; Preference

Objective To determine whether the image quality (IQ) is improved with iterative reconstruction in image space (IRIS), and whether IRIS can be used for radiation reduction in chest CT. Materials and Methods Standard dose chest CT (SDCT) in 50 patients and low dose chest CT (LDCT) in another 50 patients were performed, using a dual-source CT, with 120 kVp and same reference mAs (50 mAs for SDCT and 25 mAs for LDCT) employed to both tubes by modifying a dual-energy scan mode. Full-dose data were obtained by combining the data from both tubes and half-dose data were separated from a single tube. These were reconstructed by using a filtered back projection (FBP) and IRIS: full-dose FBP (F-FBP); full-dose IRIS (F-IRIS); half-dose FBP (H-FBP) and half-dose IRIS (H-IRIS). Objective noise was measured. The subjective IQ was evaluated by radiologists for the followings: noise, contrast and sharpness of mediastinum and lung. Results Objective noise was significantly lower in H-IRIS than in F-FBP (p < 0.01). In both SDCT and LDCT, the IQ scores were highest in F-IRIS, followed by F-FBP, H-IRIS and H-FBP, except those for sharpness of mediastinum, which tended to be higher in FBP. When comparing CT images between the same dose and different reconstruction (F-IRIS/F-FBP and H-IRIS/H-FBP) algorithms, scores tended to be higher in IRIS than in FBP, being more distinct in half-dose images. However, despite the use of IRIS, the scores were lower in H-IRIS than in F-FBP. Conclusion IRIS generally helps improve the IQ, being more distinct at the reduced radiation. However, reduced radiation by half results in IQ decrease even when using IRIS in chest CT.

Organized hematoma (OH) of the maxillary sinus is a rare benign mass that exhibits locally invasive features (1). Despite the histologically benign nature of this lesion, accurate preoperative diagnosis is important for therapeutic strategies because a simple complete resection via endoscopic sinus surgery or a Caldwell-Luc operation is sufficient to cure OH, instead of extensive surgical approaches (2-4). There have been several reports regarding the OH in the maxillary sinus observed by computed tomography (CT) and magnetic resonance (MR) imaging. However, it is occasionally still difficult to diagnose this mass precisely based only on CT and MR imaging, owing to its variable shapes and enhancement patterns (2, 5-7). In this study, we present CT, MR imaging, and 18F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) data for two cases of maxillary sinus OH mimicking inverted papilloma. We then correlated these findings with clinical and pathologic findings.

Purpose: With the advent of MSCT, the detection rate of small pulmonary nodules is markedly greater. However, there is no definite diagnostic clue to differentiate between malignant and benign nodules, except for the interval growth in small nodule less than 1 cm in diameter. We evaluated the accuracy of computeraided volumetry (CAV) and compared it with 4 radiologists' measurement. Materials and Methods: Fifteen artificial nodules that were embedded in the ex vivo porcine lung were scanned by MSCT. The diameters and volumes of nodules were independently measured three times, at 5-day intervals, and by four radiologists as well as by CAV. We evaluated the accuracy of the measurements on the basis of the true diameter and volume of the nodules. Using a paired t-test and a Bland-Altman plot, we evaluated whether there was a statistically significant difference between the radiologists' measurements and the CAV. Results: The accuracy of the manual measurements by radiologists revealed a statistically significant difference from the true diameter and volume of the artificial nodules (p0.01) Conclusion: The results of this study suggest that CAV is an accurate and useful tool to evaluate the volume of pulmonary nodules and can eventually be used to differentiate malignant and benign nodules as well as evaluate the therapeutic response of lung cancer.

Purpose: To develop an automated classification system for the differentiation of obstructive lung diseases based on the textural analysis of HRCT images, and to evaluate the accuracy and usefulness of the system. Materials and Methods: For textural analysis, histogram features, gradient features, run length encoding, and a co-occurrence matrix were employed. A Bayesian classifier was used for automated classification. The images (image number n=256) were selected from the HRCT images obtained from 17 healthy subjects (n=67), 26 patients with bronchiolitis obliterans (n=70), 28 patients with mild centrilobular emphysema (n=65), and 21 patients with panlobular emphysema or severe centrilobular emphysema (n=63). An five-fold cross-validation method was used to assess the performance of the system. Class-specific sensitivities were analyzed and the overall accuracy of the system was assessed with kappa statistics. Results: The sensitivity of the system for each class was as follows: normal lung 84.9%, bronchiolitis obliterans 83.8%, mild centrilobular emphysema 77.0%, and panlobular emphysema or severe centrilobular emphysema 95.8%. The overall performance for differentiating each disease and the normal lung was satisfactory with a kappa value of 0.779. Conclusion: An automated classification system for the differentiation between obstructive lung diseases based on the textural analysis of HRCT images was developed. The proposed system discriminates well between the various obstructive lung diseases and the normal lung.

Purpose: To suggest the characteristic MR features and to evaluate the usefulness of MR imaging for the diag-nosis of neuro-Behcet ’s disease. Materials and Methods: We retrospectively reviewed the MR findings of clinically confirmed neuro-Behcet ’s disease in eight patients (M:F = 7:1) ranging in age from 28 to 47 (average, 36) years. The findings were ana-lyzed in terms of the most frequently occurring sites, signal intensities, contrast enhancement, and the changing patterns seen on follow-up MR examination. Results: Seven of the eight patients had parenchymal brain lesions and the other had dural sinus thrombosis without brain parenchymal brain abnormality. In descending order of frequency, lesions involved the pons, midbrain, medulla oblongata, internal capsule, basal ganglia, thalamus, temporal lobe, and corpus callosum. The brain stem was involved in six patients, five of whom showed extensive involvement of the entire stem. In five patients, brain stem lesions showed supratentorial involvement, and in one, involvement of this region only was noted. Signal intensities of the lesions were poorly defined and extensive, especially in the brain stem, and usually showed prolongation of both T1 and T2 relaxation time. Three patients underwent follow-up examination, and this showed that while most lesions had disappeared in time, some had become small and cavitary. Initial MR examination showed that three patients had newly developed lesions as well as cavitary foci, suggesting the recurrence of disease. Contrast enhancement was noted in five of seven patients (71%), and various types, including nodular, linear, marginal, and ring. Conclusion: The MR features of neuro-Behcet ’s disease were fairly characteristic, and in clinically unsuspi-cious patients might be diagnostically useful.