Angiolipoma of the Posterior Mediastinum with Extension into the Spinal Canal: A Case Report

Angiolipoma is a rare benign soft tissue tumor, an unusual variant of lipoma, consisting of fatty and vascular components and located in the subcutis, usually in the trunk and extremities. We report a case of posterior mediastinal angiolipoma extending into the spinal canal and showing both fat and angiomatous features on CT scan.     

腰椎间孔上隐窝狭窄的旁正中矢状面CT影像学

目的：提高对腰椎间孔上隐窝狭窄在旁正中矢状面CT改变的认识。材料和方法：对100例腰椎间孔上隐窝狭窄病人进行螺旋CT扫描，并进行旁正中矢状面CT重建，在腰椎旁正中矢状面观察腰椎间孔上隐窝狭窄的形态学改变。结果：腰椎间孔上隐窝狭窄在旁正中矢状面CT图像上表现为：①椎间隙变窄，造成椎间孔上下变窄，占63％。②上关节突增生、肥大及骨赘形成，造成椎间孔上隐窝前后变窄，占20％。③椎体上、下缘骨赘形成，造成椎间孔上隐窝变窄，占10％。④椎体前下滑移，导致椎间孔上下隐窝错位，引起椎间孔上隐窝狭窄，占7％。结论：旁正中矢状面CT重建图像在观察腰椎间孔上隐窝狭窄比常规CT横断面更敏感。能充分显示腰椎间孔上隐窝狭窄的形态学改变，为腰椎间孔上隐窝狭窄的诊断提供可靠的影像学根据。     

Teratoma with Malignant Transformation in the Anterior Mediastinum: A Case Report

Malignant transformation of teratoma in the anterior mediastinum is rare; the mass usually has a long history and is seen in older patients. We report a case of teratoma with malignant transformation in the anterior mediastinum, complicated by rupture. CT revealed a lobulated, inhomogeneous cystic mass with a fat component and wall calcifications. The lateral wall was disrupted and consolidation in the adjacent left upper lobe was noted, suggesting rupture. A heterogeneously enhanced solid portion, obliterating the fat plane between the mass and the great vessels was present in the medial aspect of the mass, and pathologic examination demonstrated the presence of adenocarcinoma.     

Anterior mediastinal tumors: diagnostic accuracy of CT and MRI

Purpose

To compare the diagnostic accuracy for anterior mediastinal tumors among CT, MRI, and both CT and MRI, and to determine the optimal CT and MRI procedures for the diagnosis of anterior mediastinal tumors.

Materials and methods

Both CT and MRI were performed in 127 patients with pathologically diagnosed anterior mediastinal tumors. The patients included 48 cases of thymoma, 12 cases of thymic carcinoma, 12 cases of thymic cyst, 20 cases of mature teratoma, 13 cases of malignant germ cell tumor, and 22 cases of malignant lymphoma. The CT and MRI scans were assessed by two chest radiologists without knowledge of their clinical and pathologic data. The observers recorded various CT and MRI findings and their first choice of diagnosis.

Results

The two observers made a correct first-choice diagnosis in an average of 78 (61%) of 127 cases on CT, 71 (56%) of 127 cases on MRI, and 85.5 (67%) of 127 cases on both CT and MRI. These included 83% cases of thymoma on CT, 84% on MRI, and 85% on both CT and MRI; 38% cases of thymic carcinoma on CT and 13% on MRI, and 33% on both CT and MRI; 46% cases of thymic cyst on CT and 71% on MRI, and 63% on both CT and MRI; 58% cases of mature teratoma and 38% on MRI, and 78% on both CT and MRI; 35% cases of malignant germ cell tumor on CT and 27% on MRI, and 31% on both CT and MRI; and 55% cases of malignant lymphoma on CT and 43% on MRI, and 61% on both CT and MRI. There were significant differences between the diagnostic accuracy by CT and MRI in the cases with both thymic cysts and thymic carcinoma (p < 0.05).

Conclusion

CT is equal or superior to MRI in the diagnosis of anterior mediastinal tumors except for thymic cyst. CT should be considered the modality of choice following chest radiography, however, in certain circumstances, such as thymic cyst with hemorrhage or inflammation which mimic solid tumor despite low enhancement, MRI may be better in distinguishing anterior mediastinal tumors. For more helpful information in the diagnosis of mature teratoma after CT, MRI may follow.     

Mediastinal lymphangioma in adults: CT and MR imaging features

Adult mediastinal lymphangiomas are rare lesions the diagnosis of which is difficult based on imaging studies. A retrospective study of CT, MR, and pathologic findings of mediastinal lymphangioma was performed in order to correlate pathological and imaging findings. Nine cases of adult lymphangiomas were identified in the records of our institution over a 12-year period. The CT, MR, and pathologic findings were reviewed. Lesions were classified pathologically as unilocular, cavernous, and intermediate types. Pathologic examination identified six cases of unilocular lesion, two cases of cavernous type, and one intermediate type. The CT features (n = 9) included a smoothly marginated non-enhancing mass of water attenuation (n = 7), a non-enhancing mass of soft tissue attenuation (n = 1), and an enhancing multiseptated mass (n = 1). Lesions were located in the anterior mediastinum (n = 2), right paratracheal (n = 4), subcarinal (n = 1), aortopulmonic window (n = 1) areas, and below the left hilum extending into the posterior mediastinum (n = 1). The MR features (n = 3) were characterized by an enhancing multicystic and multiseptated appearance, evocative of a cavernous type in two cases. The CT appearance of mediastinal thoracic lymphangioma is variable depending on the pathologic type. The most common unilocular type is a non-enhancing thin-walled mass on CT. A less frequent cavernous type can be suggested based on a multiseptated and loculated mass on CT and/or MR examination. Received: 21 June 1999; Revised: 30 September 1999; Accepted: 23 February 2000     

Acute Aortic Syndrome and Blunt Traumatic Aortic Injury: Pictorial review of MDCT imaging

Thoracic aortic emergencies have high mortality and morbidity and should be diagnosed accurately and treated promptly. Advances in treatment options have increased survival and management choices heavily depend on imaging findings. Speed, accuracy and availability have made Multi Detector Computer Tomography (MDCT) the first line modality in evaluating thoracic aortic emergencies and radiologists should be familiar with findings in these conditions. In this paper a pictorial review of the Acute Aortic Syndrome and Blunt Traumatic Aortic Injury will be given.     

CT Findings of an Ectopic Pancreas in the Anterior Mediastinum

We report here on a rare case of an ectopic pancreatic tissue in the anterior mediastinum. A 32-year-old woman without any symptoms was transferred to our hospital because of an abnormal large mediastinal shadow on her chest radiograph during a checkup. The computed tomography (CT) scan revealed a giant cystic-solid mass that measured 16 × 13 × 8 cm and it was located in the center of the anterior mediastinum and it symmetrically grew to two sides. On enhanced CT scans, the solid component of the mass showed marked enhancement. We performed total surgical resection of the mass and complete pancreatic tissues were verified on the pathological examination.     

Unusual Thymic Hyperplasia Mimicking Lipomatous Tumor in an Eight-Year-Old Boy with Concomitant Pericardial Lipomatosis and Right Facial Hemihypertrophy

We report a case of thymic hyperplasia accompanied by pericardial lipomatosis and right facial hemihypertrophy in an 8-year-old boy. On imaging studies, the hyperplastic thymus had prominent curvilinear and nodular fatty areas simulating a fat-containing anterior mediastinal mass, which is an unusual finding in children. To our knowledge, this is the first report on a child with a combination of thymic hyperplasia, pericardial lipomatosis, and right facial hemihypertrophy. The radiologic findings are presented with a brief discussion.     

Assessment of the Right Ventricular Function and Mass Using Cardiac Multi-Detector Computed Tomography in Patients with Chronic Obstructive Pulmonary Disease

Objective

We wanted to assess the relationship between measurements of the right ventricular (RV) function and mass, with using cardiac multi-detector computed tomography (MDCT) and the severity of chronic obstructive pulmonary disease (COPD) as determined by the pulmonary function test (PFT).

Materials and Methods

Measurements of PFT and cardiac MDCT were obtained in 33 COPD patients. Using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification, the patients were divided into three groups according to the severity of the disease: stage I (mild, n = 4), stage II (moderate, n = 15) and stage III (severe, n = 14). The RV function and the wall mass were obtained by cardiac MDCT. The results were compared among the groups using the Student-Newman-Keuls method. Pearson''s correlation was used to evaluate the relationship between the right ventricular ejection fraction (RVEF) and the wall mass results with the PFT results. P-values less than 0.05 were considered statistically significant.

Results

The RVEF and mass were 47±3% and 41±2 g in stage I, 46±6% and 46±5 g in stage II, and 35±5% and 55±6 g in stage III, respectively. The RVEF was significantly lower in stage III than in stage I and II (p < 0.01). The RV mass was significantly different among the three stages, according to the disease severity of COPD (p < 0.05). The correlation was excellent between the MDCT results and forced expiratory volume in 1 sec (r = 0.797 for RVEF and r = -0.769 for RV mass) and forced expiratory volume in 1 sec to the forced vital capacity (r = 0.745 for RVEF and r = -0.718 for RV mass).

Conclusion

Our study shows that the mean RV wall mass as measured by cardiac MDCT correlates well with the COPD disease severity as determined by PFT.     

Posterior Lung Herniation in Pulmonary Agenesis and Aplasia: Chest Radiograph and Cross-Sectional Imaging Correlation

ObjectiveTo describe the anatomic locations and imaging features of posterior lung herniation in unilateral pulmonary agenesis and aplasia, focusing on radiograph-CT/MRI correlation.Materials and MethodsA total of 10 patients (seven with pulmonary agenesis and three with pulmonary aplasia, male: female = 1:9, mean age 7.3 years, age range from 1 month to 20 years) were included. Chest radiographs (n = 9), CT (n = 9), and MRI (n = 1) were reviewed to assess the type of lung underdevelopment, presence of anterior and posterior lung herniation, bronchus origin, supplying artery, and draining vein of the herniated lung.ResultsPulmonary agenesis/aplasia more commonly affected the left lung (n = 7) than the right lung (n = 3). Anterior lung herniation was observed in nine of the 10 patients. Posterior lung herniation was observed in seven patients with left pulmonary agenesis/aplasia. Two patients showed posterior lung herniation crossing the midline but not beyond the aorta, and five patients showed the posteriorly herniated right lower lobe crossing the midline to extend into the left hemithorax farther beyond the descending thoracic aorta through the space between the esophagus and the aorta. This anatomical configuration resulted in a characteristic radiographic finding of a radiolucent area with a convex lateral border and a vertical medial border in the left lower lung zone, revealing a tongue-like projection on CT and MRI.ConclusionPosterior lung herniation occurs in unilateral left lung agenesis/aplasia. Approximately 70% of the cases of posterior lung herniation reveal a unique radiolucent tongue-like projection in the left lower lung zone on imaging studies, which is caused by the extension of the posteriorly herniated right lung farther beyond the descending aorta.     

Assessment of ureteral obstruction in patients with compromised renal function: Value of Curved Planar Reformations in MDCT

Objective

To evaluate the usefulness of MDCT using a curved planar reformation technique for the noninvasive assessment of the causes and level of ureteral obstruction in patients with compromised renal function.

Patients and methods

Between January 2012 and February 2013, 50 patients with clinical and sonographic manifestations of ureteral obstruction underwent non-contrast multidetector CT (MDCT) using a 16-slice machine. A total of 65 ureters were examined. Curved planar reformation images were performed to display the entire course of ureters in the same image. All patients had renal impairment with serum creatinine greater than 2.0 mg/dl. The gold standard for diagnosis of the cause of obstruction was ureteroscopy and/or open surgery. The sensitivity, specificity and overall accuracy of MDCT using curved planar reformation in the diagnosis of ureteral obstruction were calculated in comparison with the gold standard.

Results

A total of 65 ureters were examined (35 unilateral, 15 bilateral). The most common cause of ureteric obstruction was ureteric stone representing 27/65 (41.5%), followed by ureteric stricture representing 23/65 (35.4%). The lower third was the most affected in our study, it was encountered in 38/65 ureters (58.46%). The total sensitivity, specificity and accuracy of CPR for the cause of the ureteric obstruction were 98.5%, 98.5% and 97.8%, respectively (P value >0.05). CPR also was more sensitive and accurate for the level of ureteral obstruction with a total sensitivity of 100% and accuracy of 100% (P value >0.001).

Conclusion

Curved planar reformation MDCT is a useful noninvasive technique which is accurate in diagnosing the cause and level of ureteral obstruction in patients with compromised renal functions and is helpful for planning the therapeutic management of such patients.     

Assessment of coronary artery stents using 16-slice MDCT angiography: evaluation of a dedicated reconstruction kernel and a noise reduction filter

To compare the effect of different reconstruction kernels and a noise-reducing postprocessing filter on the delineation of coronary artery stents in 16-slice CT-angiography. Ten patients with coronary stents (seven LAD, five RCX and three RCA) were examined with a 16-slice MDCT using standard acquisition parameters. Images were reconstructed using a medium soft (B30f) and a dedicated, edge-enhancing kernel (B46f). Additional postprocessing with an edge-preserving filter was performed on B46f images to reduce the image noise. In multiplanar reformations (MPRs) along and perpendicular to the stent axis, intraluminal attenuation values and the visible lumen diameter were measured. Image noise was measured in the subcutaneous fat using a region of interest (ROI) technique. Arterial enhancement in the aorta was 275.1 HU. Attenuation in the stent lumen was 390.4, 340.0 and 346.8 HU in MPRs derived from B30f, original B46 and postprocessed B46f images. The mean noise level was 20.4, 35.0 and 24.9 HU respectively. The visible lumen diameter was significantly greater in B46f and postprocessed B46f images (2.17 and 2.16 mm), compared to 1.93 mm in B30f images (p<0.01). Edge-enhancing reconstruction kernels increase the visible stent lumen, but also increase image noise. Dedicated postprocessing filters can reduce the introduced noise without a loss of spatial resolution.     

Appearances of mediastinal and pulmonary hilar lymph nodes on thin-section CT: comparison with 5 mm slice thickness CT

AIM: This study aimed to evaluate the efficacy of thin-section CT of the mediastinum in the assessment of thoracic lymph nodes in comparison with conventional CT. MATERIALS AND METHODS: A total of 193 CT examinations from 193 patients with suspected pulmonary disease were reconstructed into thin-section CT and conventional CT. The appearances of the lymph nodes were assessed and compared between thin-section CT and conventional CT. RESULTS: Intranodal fat was more often detected on thin-section CT than on conventional CT (P<.001). There were no statistically significant differences in the frequencies of inhomogeneous enhancement and bulging margin of the hilar lymph node. CONCLUSION: Thin-section CT can improve clinical N-staging of lung cancer due to classification of enlarged mediastinal lymph nodes as benign based on identification of intranodal fat.     

Mediastinal lymphadenopathy in congestive heart failure: a sequential CT evaluation with clinical and echocardiographic correlations

The aim of this study was to evaluate the frequency and evolution after treatment of mediastinal lymphadenopathy associated with congestive left heart failure on CT scans in correlation with clinical and echocardiographic findings. Thirty-one consecutive patients with subacute left heart failure underwent a clinical evaluation using the NYHA classification, a CT examination, and transthoracic echocardiography at the time of initial presentation (T1). After initiation of medical treatment (T2), follow-up CT scans were systematically obtained together with a clinical evaluation. At T1, all patients showed severe (type III: n=12, 39%; type IV: n=12, 39%) to moderate (type I, n=1, 3%; type II, n=6, 19%) dyspnea with a mean ejection fraction of 39% (range 22–74%). On initial CT scans, enlarged mediastinal lymph nodes were seen in 13 patients (42%) with blurred contours in 5 patients (16%) and hazy mediastinal fat in 1 patient (3%). Significant decrease in the size of lymphadenopathy was observed between T1 and T2 (T1, n=13, 42% vs T2, n=10, 32%; p<0.05) with a concurrent decrease in the severity of dyspnea (grade III–IV dyspnea at T1, n=24, 78% vs grade I–II dyspnea at T2, n=26, 83.5%). Patients with enlarged lymph nodes at T1 showed: (a) a significantly lower ejection fraction at echocardiography than those without lymphadenopathy (mean±SD value: 34±12.9 vs 43±13.8%; p=0.04); (b) a significantly larger diameter of the right superior pulmonary vein (mean±SD value: 17±2.75 vs 14±3.9 mm; p=0.04); and (c) a higher frequency of abnormal peribronchovascular thickening (n=5 vs n=1; p=0.06). Mediastinal lymphadenopathy associated with subacute left heart failure was observed in 13 patients (42%), showing regression after initiation of treatment in 8 of 13 patients (62%).     

Aortic ostia of the bronchial arteries and tracheal bifurcation: MDCT analysis

AIM:To explore the anatomical relationships between bronchial artery and tracheal bifurcation using computed tomography angiography (CTA).METHODS:One hundred consecutive patients (84 men,16 women;aged 46-85 years) who underwent CTA using multi-detector row CT (MDCT) were investigated retrospectively.The distance between sites of bronchial artery ostia and tracheal bifurcation,and dividing directions were explored.The directions of division from the descending aorta were described as on a clock face.RESULTS:We identified ostia of 198 bronchial arteries:95 right bronchial arteries,67 left bronchial arteries,36 common trunk arteries.Of these,172 (87%) divided from the descending aorta,25 (13%) from the aortic arch,and 1 (0.5%) from the left subclavian artery.The right,left,and common trunk bronchial arteries divided at-1 to 2 cm from tracheal bifurcation with frequencies of 77% (73/95),82% (54/66),and 70% (25/36),respectively.The dividing direction of right bronchial arteries from the descending aorta was 9 to 10 o’clock with a frequency of 81% (64/79);that of left and common tract bronchial arteries was 11 to 1 o’clock with frequencies of 70% (43/62) and 77% (24/31),respectively.CONCLUSION:CTA using MDCT provides details of the relation between bronchial artery ostia and tracheal bifurcation.     

Mediastinal and pericardial hydatidosis: A case report with review of the literature

Hydatidosis is an echinococcosis caused by the development of Echinococcus granulosus larvae in humans. The lung is the second most frequent site after the liver. The primary mediastinal and pericardial localisations are extremely rare.Ultrasound and CT scans play an important role in the diagnosis of this disease.We report the case of an 11-year-old female patient from a rural environment with a history of dogs contact, whose symptomatology consisted of chest pain, dyspnoea, all evolving in a febrile context. The imagery showed the existence of multiple mediastinal and pericardial collections. This patient was rapidly managed with albendazole (ABZ) and scanography revealed an excellent therapeutic response.Primary mediastinal and pericardial hydatidosis is a very uncommon disease. It can be unfortunately revealed at the stage of vital prognosis complications. Ultrasound and computerized tomography (CT) are helpful for localizing and defining the morphologic features of hydatid cysts. It should be kept in mind, especially in patients from endemic areas.     

Tools of the trade for CTA: MDCT scanners and contrast medium injection protocols

The introduction of multi-detector row computed tomography (MDCT) scanners in 1998 ushered in new advances in CT angiography (CTA). The subsequent expansion of MDCT scanner capabilities, coupled with advances in understanding of contrast medium (CM) dynamics, has further improved the clinical availability and consistency of CTA. We will review recent advances in CT scanner technology and discuss early CM dynamics. Specifically, we describe an approach tailored to the available scanner technology and to patient size aimed at providing consistently robust CTA studies across all vascular territories. A rational method to design combined CTA scan/injection protocols to facilitate this goal will be described. Our current experience with a simplified protocol for CTA with 64-MDCT will also be explained.     

Right Ventricular Mass Quantification Using Cardiac CT and a Semiautomatic Three-Dimensional Hybrid Segmentation Approach: A Pilot Study

ObjectiveTo evaluate the technical applicability of a semiautomatic three-dimensional (3D) hybrid CT segmentation method for the quantification of right ventricular mass in patients with cardiovascular disease.Materials and MethodsCardiac CT (270 cardiac phases) was used to quantify right ventricular mass using a semiautomatic 3D hybrid segmentation method in 195 patients with cardiovascular disease. Data from 270 cardiac phases were divided into subgroups based on the extent of the segmentation error (no error; ≤ 10% error; > 10% error [technical failure]), defined as discontinuous areas in the right ventricular myocardium. The reproducibility of the right ventricular mass quantification was assessed. In patients with no error or < 10% error, the right ventricular mass was compared and correlated between paired end-systolic and end-diastolic data. The error rate and right ventricular mass were compared based on right ventricular hypertrophy groups.ResultsThe quantification of right ventricular mass was technically applicable in 96.3% (260/270) of CT data, with no error in 54.4% (147/270) and ≤ 10% error in 41.9% (113/270) of cases. Technical failure was observed in 3.7% (10/270) of cases. The reproducibility of the quantification was high (intraclass correlation coefficient = 0.999, p < 0.001). The indexed mass was significantly greater at end-systole than at end-diastole (45.9 ± 22.1 g/m² vs. 39.7 ± 20.2 g/m², p < 0.001), and paired values were highly correlated (r = 0.96, p < 0.001). Fewer errors were observed in severe right ventricular hypertrophy and at the end-systolic phase. The indexed right ventricular mass was significantly higher in severe right ventricular hypertrophy (p < 0.02), except in the comparison of the end-diastolic data between no hypertrophy and mild hypertrophy groups (p > 0.1).ConclusionCT quantification of right ventricular mass using a semiautomatic 3D hybrid segmentation is technically applicable with high reproducibility in most patients with cardiovascular disease.     

SARS的胸部CR和CT动态改变

目的 :研究SARS胸部CR和CT的动态改变。材料和方法 :回顾性分析和研究 47例SARS一系列胸部CR和CT资料。结果 :47例均有异常发现。起病 1～ 3天 ,异常发现包括单发小圆形磨玻璃密度影 2 0例 ,小结节 2 1例 ,单发大结节 3例和局部磨玻璃斑片影 3例。 74.5 % ( 3 5 /4 7)位于单侧肺 ,63 .8% ( 3 0 /4 7)分布于中下肺野 ,63 .8% ( 3 0 /4 7)位于中外带。发病后 1周病变迅速进展 ,范围扩大 2 7例 ,病变增大或双侧侵犯 10例 ,在磨玻璃密度影内出现结节或带条影 10例。发病后 2～ 3周 ,病变继续增大 10例 ,肺实变 8例和肺不张 3例 ,但 2 6例病变开始吸收。出院后 2周 ,6例胸部CR示残留条索或斑片影 ,但其中 1例 2周后再胸部CR复查显示残留索条影完全吸收。结论 :SARS的胸部CR和CT的动态改变能反映其病理改变 ,并为临床诊疗提供重要和可靠的信息。