CT demonstration of a giant adrenal endothelial cyst of the angiomatous subtype

Adrenal cysts are uncommon lesions with only approximately 300 having been reported to date. Histologically, they are heterogeneous in nature with angiomatous endothelial cysts being quite rare. The computed tomography of a woman with a very large cyst of this variety displayed thin walls with a few septations and foci of soft tissue within. The possibility of a large cystic mass originating from the adrenal gland must be considered in the diagnosis when a large abdominal mass is encountered.     

Cystic primary neoplasms of the liver of the adult CT features

Although rather rare, primary cystic neoplasms of the liver of the adult may represent a diagnostic challenge in everyday practice. We describe the features of such tumors visualized on computed tomography. This shows a wide range of morphological changes such as septa, papillary growths, solid/liquid ratio, wall characteristics, and vascularization. We conclude that although the differential diagnosis between these tumors and nontumoral cystic lesions may occasionally be reliable on computed tomography, proper management of hepatic cystic neoplasms still relies on the pathological findings.     

A recurrent left atrium leiomyosarcoma

Cardiac leiomyosarcoma is a rare tumour which can grow either intramurally or extramurally. Its prognosis is dismal. Surgery lengthens survival, but recurrences usually occur in the short term. Gated MRI is useful for the assessment of cardiac masses since it provides fine spatial and contrast resolution. We present the case of a left atrial leiomyosarcoma whose recurrence was diagnosed by gated MRI. Our patient underwent a second resection but died soon after. Received 13 September 1996; Revision received 13 February 1997; Accepted 27 May 1997     

Aberrant left subclavian artery aneurysm with esophago arterial fistula CT demonstration

Esophagoarterial fistula is a rare but life-threatening complication of an aberrant subclavian artery aneurysm. We report the computed tomography appearance of such a fistula. The characteristic location, presence of rim calcification, and interspersed air and thrombus allowed for prompt preoperative diagnosis and surgery.     

CT scans through metal scanning technique versus hardware composition

Objective: Streak artifact on CT scans of metal containing areas has been a long standing problem. Although several artifact reducing methods have been used to improve image quality, most have been limited by requiring specialized equipment or lengthy complex calculations that are not automated. Others have shown that increasing the beam energy results in increased thickness of metal that may be imaged by CT without severe image degradation. We have studied the image quality of bone surrounding metal both with titanium and cobalt-chrome prostheses using various scanning techniques. Methods: In a double blind fashion, 28 radiology residents and attendings were surveyed as to the best technique for imaging bone detail surrounding metal. A series of images was arranged of an implanted titanium prosthesis, a cobalt-chrome prosthesis and a pelvis repaired with stainless steel pelvic reconstruction plates. Scans were performed using three techniques: 120 kVp, 170 mA, 2 s, 360° rotation, 140 kVp,140 mA, 3 s, 360° rotation, 140 kVp, 140 mA, 4 s, 420° rotation. Results: Titanium was superior to cobalt-chrome (p < .0001 Wilcoxon Signed Rank Test). No advantage was noted for higher kVp or increased scan arc of 420° compared to the standard 360°. Conclusion: Titanium allows improved bone detail surround the metal than CT cobalt-chrome. We have found no advantage to using either high kVp or a 420° scan are to improve the image quality of bone surrounded by metal.     

Inferior vena cava interruption with renal vein collar continuation: CT and MRI appearance

The CT and MRI appearance of an inferior vena cava (IVC) interruption with renal venous collar continuation is presented. CT and MRI identify and define venous anomalies without the need for invasive angiography. Knowledge of an anomalous IVC is important to the vascular and transplant surgeon as well as to the interventional radiologist.     

Multidetector CT of left atrium

MDCT angiography has enabled visualization of left atrium in addition to coronary arteries. CT images can be utilized to demonstrate normal anatomy and pathologies. Left atrium variations and pathologies include atrial septal pouch, patent foramen ovale, atrial septal defect, atrial band, lipomatous hypertrophy, cor triatriatum, diverticulum, accessory appendages, atrial thrombus and masses. Left atrium should be carefully evaluated in patients undergoing coronary CT angiography. MDCT is becoming an alternative modality for the evaluation of left atrium.     

左心房憩室样结构的双源CT成像

目的:利用双源CT血管造影评价左心房憩室样结构的发生率、发生部位及形态学变化。方法:随机搜集的415例成人冠状动脉双源CT血管造影图像进行回顾性分析。结果:发现左心房憩室样结构85例,检出率为20.5%(85/415),总计87个憩室(2例有2个憩室)位于左房上壁77例及下壁8例,憩室底部开口0.5～1.1cm,平均0.8cm,深度0.6～1.2cm,平均0.9cm,底部形态呈尖角状或不规则菜花状。结论:双源CT血管成像能够清晰显示左心房憩室的发生部位及形态变化,有利于临床进行电生理治疗的术前评估。     

Retroperitoneal lymphangioleiomyomatosis: CT appearance

Lymphangioleiomyomatosis is a rare disease involving the lung, lymphatic trunk and lymph nodes. Sometimes it appears in the retroperitoneum with or without subsequent development in the lungs. We present a 52-year-old woman with retroperitoneal location of the disease. We discuss the abdominal CT appearance, the cytologic and immunophenotypic features and a preoperative differential diagnosis is attempted. Received: 10 June 1997; Revision received 28 July 1997, Accepted 8 September 1997     

CT of rhabdomyolysis associated with malignant hyperthermia and seizures

Computed tomography evaluation in rhabdomyolysis can reveal muscle necrosis and calcification. We report the computed tomography findings in acute rhabdomyolysis, secondary to hyperthermia and seizures. KEY WORDS:     

CT demonstration of normal gastric wall thickness: The value of administering gasproducing and paralytic agents

The: authors analysed the CT-findings in 100 normal subjects who underwent a modified doublecontrast technique (D.C.). The mean gastric wall thickness in four areas was measured and the contribution of the D.C. technique is discussed.     

Comparison of spiral CT and conventional CT in 3D visualization of facial trauma: work in progress

Spiral computed tomography (SCT) differs from conventional CT (CCT) in that regions of the body can be rapidly imaged via continuous scanning. This is accompanied by simultaneous advancement of the patient, thus allowing volumetric data acquisition of up to 60 cm in less than a minute. Thus motion is minimized and slice misregistration is minimized when multiplanar and three dimensional reconstructions are performed. This paper compares the utility of SCT and CCT in facial trauma. A total of six patients were studied with either CCT or SCT of the face after trauma. SCr scans were obtained using a Siemens Somatom Plus-S Cr scanner (2 mm thick collimation and 3 mm/sec table feed for 32 s). Three-dimensional (3D) and multiplanar reconstruction images of the facial bones were generated after appropriate thresholds were selected by the radiologist; similar images generated with a CCT (GE quick 9800) were compared using a three point scale with kappa analysis. SCT is able to generate axial and reformatted images of comparable quality to CCT (k = 0.47–0.89) in less than half the time to perform an examination (26 min vs 63 min). SCT can rapidly produce (3D) and multiplanar reformatted images of facial trauma with minimal motion, or misregistration artifact when compared to CCT.     

CT appearances in macronodular hepatosplenic tuberculosis: A review with five additional new cases

Pseudotumoral or macronodular hepatosplenic tuberculosis (HSTB) is rare. Only 31 cases have been documented in imaging literature so far. Presented is the clinico-imaging review with five additional new cases of this uncommon variety. Due to nonspecific wide spectrum of imaging appearances, biopsy is mandatory in almost all cases. Clinical recovery and resolution of lesions on imaging may not be directly proportional.     

Metastatic hypernephroma masquerading as acute cholecystitis

Renal cell carcinoma can metastasize to multiple anatomic sites. The metastasis may simulate certain disease entities depending on the location and particular organ involved. It is important to recognize that these metastases can present many years after the primary tumor has been treated. We present a case in which a primary hypernephroma was surgically removed and subsequently 13 years later presented with metastatic disease to the gallbladder clinically simulating acute cholecystitis.     

CT manifestation of non-Hodgkin''s lymphoma as a solitary pulmonary nodule in a patient with acquired immunodeficiency syndrome

We present a case of acquired immunodeficiency syndrome with primary pulmonary non-Hodgkin's lymphoma that manifested as a solitary pleura-based mass lesion. Its differentiation from an infectious process imposed a diagnostic dilemma. The importance of awareness of such an entity for earlier diagnosis is stressed.     

Multidetector helical computed tomography of the liver: comparison of hepatic enhancement using two different contrast media strategies

RATIONALE AND OBJECTIVES: The purpose of this study was to compare hepatic enhancement characteristics using two different contrast media injection protocols with multidetector helical computed tomography. MATERIALS AND METHODS: Twenty-three patients with known or suspected liver lesions scheduled to undergo biphasic hepatic multidetector helical computed tomography were randomized into one of two groups: (1) 150 mL of iopamidol (300 mgI/mL) at 5 mL/second, or (2) 100 mL of iopamidol (370 mgI/mL) at 4 mL/second. Unenhanced images were acquired initially, followed by both hepatic arterial phase (scan delay, 33 seconds) and portal venous phase (PVP; scan delay, 65 seconds) imaging. Three abdominal radiologists independently graded the images on a scale from 1-5 for enhancement and overall scan quality. Time-attenuation curves were generated from operator-defined region-of-interest measurements of liver parenchyma and aorta. RESULTS: Qualitatively, the three reviewers found no significant difference between the two study groups in terms of overall scan quality (P = .23) or aortic enhancement (hepatic arterial phase, P = .9; PVP, P = .24). However, liver enhancement during the PVP was considered to be less in the Isovue 370 group (P = .04). Quantitatively, during the hepatic arterial phase, there was no statistically significant difference between the two injection protocols comparing either aortic or hepatic parenchymal enhancement (P = .62 and .80, respectively). During the PVP, these differences were statistically significant, with both aortic and hepatic parenchymal enhancement lower in the Isovue 370 group (P < .01 and P = .04, respectively). CONCLUSION: It is important to consider the amount of iodine injected per second and the duration of the injection when setting up protocols to achieve target organ enhancement. 100 mL of iopamidol 370 at 4 mL/second can be used to obtain images of the liver with good diagnostic quality compared to more conventional protocols using 150 mL of iopamidol 300 at 5 mL/second. However, the degree of liver parenchymal enhancement during the PVP using the latter injection scheme is lower, which in turn could potentially reduce hepatic lesion conspicuity.     

Preablation assessment for the left atrium: comparison of ECG-gated cardiac CT with echocardiography

RATIONALE AND OBJECTIVES: Evaluate the role of two-dimensional echocardiography and electrocardiographically (ECG)-gated contrast-enhanced multislice computed tomographic (MSCT) cardiac imaging to assess cardiac anatomy, specifically pulmonary venous anatomy and left atrial thrombus, in a selected group of patients before catheter-based atrial fibrillation ablation. MATERIALS AND METHODS: Left atrial anatomy and associated findings in 34 consecutive patients scheduled for electrophysiologic testing who underwent both echocardiography and ECG-gated 16-slice MSCT cardiac imaging were retrospectively compared. Results from two-dimensional transthoracic echocardiography (TTE), cardiac MSCT, electrophysiologic study (EPS), and transesophageal echocardiography (TEE) (when performed) were taken from the official medical record without prior knowledge of this study when interpretation was rendered for clinical use. Electronic record review included: presence of left atrial thrombus (defined as constant filling defect on at least two echocardiographic views or filling defect on computed tomography) and location, pulmonary venous anatomy, and other cardiac, mediastinal, or pulmonary abnormalities. RESULTS: Left atrial thrombus was identified by cardiac MSCT alone in five patients (15%). Pulmonary venous variants were identified with cardiac MSCT in two patients (6%). Both MSCT and echocardiography were normal in 17 subjects (79%). Echocardiography was better at identifying associated valvular abnormalities that were seen in 10 patients (29%). Cardiac MSCT angiography alone identified other cardiac and noncardiac abnormalities, including suspicious pulmonary malignancy, mediastinal adenopathy, and coronary stenosis in 15 patients (44%). CONCLUSIONS: Echocardiography and cardiac MSCT angiography often provide complimentary findings during the preprocedural evaluation for patients with atrial fibrillation requiring ablation. Cardiac MSCT may provide significant additional information about the left atrium, mediastinum, coronary circulation, and visualized lung fields. Based on this study, we would advise that patients considered for radiofrequency ablation for uncontrolled right atrial fibrillation have both echocardiography and ECG-gated contrast-enhanced cardiac MSCT performed as part of the preprocedure evaluation.     

Thrombosis of the IVC and azygous continuation of IVC by bronchogenic cancer: CT and MRI appearance

The authors describe the computed tomography (CT) and magnetic resonance imaging (MRI) findings in a patient with thrombosis of the inferior vena cava (IVC) and azygous continuation of the IVC caused by bronchogenic carcinoma. CT has been touted as the modality of choice for mediastinal evaluation. MRI is presently considered to be the initial modality of choice for mediastinal vessel evaluation. MRI is noninvasive, there is no radiation dose to the patient, multiplanar imaging can be done, and there is no need for iodinated contrast material. The satisfactory evaluation of an individual patient may require the use of MRI and CT in a complementary fashion.     

原发性心脏血管肉瘤的CT及MRI表现

目的:探讨心脏原发性血管肉瘤的CT、MRI表现,以提高对该病的影像诊断水平。方法:回顾性分析5例经临床病理证实的心脏原发血管肉瘤患者的临床及影像资料。5例中男4例,女1例;年龄24~45岁,平均34.5岁。对肿瘤的部位、大小、形态、边缘、CT密度、MRI信号及强化形式进行分析。5例中,3例行胸部CT平扫加增强扫描,2例行CT平扫、MRI平扫及增强扫描。结果:5例心脏原发性血管肉瘤均发生在右心房游离壁,向心腔内或外生长。CT平扫表现为等或稍低密度;MRI平扫T1WI表现为与心肌信号相似的等或稍低信号,T2WI表现为不均匀稍高信号;如瘤体内有坏死、出血、钙化,则表现为混杂密度或混杂信号。CT及MRI增强扫描肿瘤呈明显不均匀延迟强化,CT增强扫描瘤体内见肿瘤血管或血管团。结论:心脏原发血管肉瘤具有一定的影像特征,掌握这些特征有助于病变的诊断及鉴别诊断。