Multidetector computed tomography diagnosis of adenomyomatosis of the gallbladder

The differentiation of gallbladder adenomyomatosis from gallbladder carcinoma is important as both conditions may present with thickening of the gallbladder wall or as a focal mass. Identification of Rokitansky-Aschoff sinuses is the key feature in making an accurate diagnosis of gallbladder adenomyomatosis on imaging studies. The diagnosis of gallbladder adenomyomatosis can be made with accurately by multidetector computed tomography when the presence of Rokitansky-Aschoff sinuses (small cystic spaces within the thickened gallbladder wall) are noted. Herein we present multidetector computed tomography findings of a 27-year-old patient with gallbladder adenomyomatosis.

Congenital variants and anomalies of the pancreas and pancreatic duct: imaging by magnetic resonance cholangiopancreaticography and multidetector computed tomography

Though congenital anomalies of the pancreas and pancreatic duct are relatively uncommon and they are often discovered as an incidental finding in asymptomatic patients, some of these anomalies may lead to various clinical symptoms such as recurrent abdominal pain, nausea and vomiting. Recognition of these anomalies is important because these anomalies may be a surgically correctable cause of recurrent pancreatitis or the cause of gastric outlet obstruction. An awareness of these anomalies may help in surgical planning and prevent inadvertent ductal injury. The purpose of this article is to review normal pancreatic embryology, the appearance of ductal anatomic variants and developmental anomalies of the pancreas, with emphasis on magnetic resonance cholangiopancreaticography and multidetector computed tomography.

MDCT angiography of isolated right subclavian artery

Isolation of a subclavian artery is an uncommon congenital anomaly of the aortic arch in which one subclavian artery loses its connection with the aorta and originates from the homolateral pulmonary artery by way of a ductus arteriosus. Isolation of the left subclavian artery in patients with a right aortic arch is well known. However, isolated right subclavian artery with a left-sided aortic arch is an extremely rare condition. In this report, we present multidetector computed tomographic (MDCT) angiography findings of an isolated right subclavian artery associated with a common carotid trunk and an anomalous origin and proximal interruption of the left pulmonary artery.

Coarctation of the aorta in adults: preoperative evaluation with multidetector CT angiography

PURPOSE

To evaluate the reliability of 16-slice multidetector computed tomographic (MDCT) angiography for the preoperative morphologic assessment of coarctation of the aorta in adults.

MATERIALS AND METHODS

Twenty-four adult patients with clinical suspicion of coarctation of the aorta who underwent both Doppler echocardiography and MDCT angiography were included in this study. The sensitivities of diagnosis were assessed comparing MDCT and Doppler echocardiography with surgical results.

RESULTS

The overall sensitivity of three-dimensional MDCT for diagnosis of the coarctation of the aorta was 100%, which was higher than that of Doppler echocardiography (91%). The overall sensitivity of MDCT for the assessment of cardiac defects was 82%, which was lower than that of Doppler echocardiography (100%).

CONCLUSION

MDCT angiography with multiplanar and three-dimensional techniques should be the method of choice for preoperative morphologic assessment of coarctation of the aorta in adult patients.

[A rare cause of aortic insufficiency: quadricuspid aortic valve]

Quadricuspid aortic valve can be documented incidentally as a rare cause of aortic regurgitation. An asymptomatic 24-year-old male patient underwent cardiac evaluation after detection of a cardiac murmur on routine examination. There was a grade 1/6 early diastolic murmur on the right upper side of the sternum. The electrocardiogram was in sinus rhythm and normal. Transthoracic echocardiography showed normal left ventricular dimensions and functions, but it did not provide an adequate visualization of valve structure. Color Doppler examination showed mild aortic insufficiency. Transesophageal echocardiography revealed a qaudricuspid aortic valve composed of two equal large cusps and two equal small cusps. Color Doppler scans demonstrated aortic regurgitant flow at the coaptation sites of small and large cusps. Further studies by aortic computed tomographic (CT) angiography and cardiac CT did not show aortic coarctation or any other coronary abnormality, but the latter confirmed quadricuspid aortic valve.

Multidetector CT urography of renal fusion anomalies

Renal fusion anomalies, in which both kidneys are fused togeher in early embyronic life, are rarely encountered. Once a fused kidney is diagnosed or suspected, further laboratory and imaging evaluation should be performed to assess the status of the kidneys and to look for treatable causes of renal pathology. The early dignosis of potential complications that can accompany this anomaly must be made in order to prevent permanent renal damage. The advantage of multidetector computed tomographic (MDCT) urography is its ability to depict the normal urinary tract anatomy, including both the renal parenchyma, and collecting structures and ureters. MDCT urography is helpful to screen for the presence of stones, hydronephrosis or masses. Additionally, it provides information about the vascular supply of the fused kidneys. Therefore, MDCT urography enables a comprehensive evaluation of patients with renal fusion anomalies in a single examination. Especially three-dimensional reformatted images can provide good delineation of congenital fusion anomalies of the kidney. In this study we report our experience with MDCT urography for the anatomic demonstration of renal fusion anomalies.

Congenital anomalies of the aortic arch: evaluation with the use of multidetector computed tomography

Congenital anomalies of the aortic arch have clinical importance, as the anomalies may be associated with vascular rings or other congenital cardiovascular diseases. Multidetector computed tomography (MDCT) angiography enables one to display the detailed anatomy of vascular structures and the spatial relationships with adjacent organs; this ability is the greatest advantage of the use of MDCT angiography in comparison to other imaging modalities in the evaluation of the congenital anomalies of the aortic arch. In this review article, we illustrate 16-slice MDCT angiography appearances of congenital anomalies of the aortic arch.

Preoperative staging of renal cell carcinoma with multidetector CT

PURPOSE

To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for preoperative staging of renal cell carcinoma (RCC) using the 1997 TNM (tumor, node, metastasis) classification.

MATERIALS AND METHODS

We conducted a retrospective review of MDCT in 57 consecutive patients with RCC performed for tumor staging before radical (n = 51) or partial nephrectomy (n = 6). The scanning protocol of MDCT consisted of unenhanced and biphasic contrast-enhanced scans during corticomedullary and nephrographic phases. MDCT and surgical-histopathologic staging were performed using the 1997 TNM staging system. The results of MDCT were compared with the histopathological results. Agreement between the two staging methods was evaluated using the kappa (kappa) statistic.

RESULTS

Consistency between MDCT and histopathologic staging was excellent for T staging (kappa= 0.87), fair for N staging (kappa= 0.40), and excellent for M staging (kappa= 1.00). Fifty-one of 57 tumors were correctly staged, five overstaged and one understaged by MDCT, with an overall accuracy of 89%. MDCT was able to correctly identify and localize the extension of the tumor thrombus in all 10 patients. In the evaluation of nodal involvement, 42 of 57 patients (74%) were correctly staged, 11 (19%) overstaged, and four (7%) understaged.

CONCLUSION

MDCT with a dynamic contrast enhancement protocol is an accurate method for preoperative staging of RCC. MDCT with multiplanar reconstruction capability enables a reliable detection and characterization of the tumor, but the involvement of lymph nodes by tumor is still difficult to predict because it is based on node size criterion only.

Noninvasive evaluation of coronary artery bypass grafts and native coronary arteries: is 16-slice multidetector CT useful?

PURPOSE

To investigate the diagnostic accuracy and limitations of 16-slice multidetector computed tomography (MDCT) in the detection of significant ( > 50%) stenosis of coronary artery bypass grafts (CABG) and native coronary arteries.

MATERIALS AND METHODS

One hundred two patients with 236 grafts were investigated by 16-slice MDCT. Native coronary arteries were also investigated. The image quality was assessed in terms of artifact, and the evaluable segments were screened for the presence of occlusion and significant ( > 50%) stenosis. MDCT results were compared with conventional coronary angiography.

RESULTS

The evaluability of MDCT was 90.4% for CABG and 71.2% for native coronary arteries. The most frequent causes of nonevaluable segments were motion artifact in venous grafts, metallic clip artifact in arterial grafts, and severe calcification in native coronary arteries. MDCT correctly diagnosed all of the 46 occluded grafts. The sensitivity, specificity, and the positive and negative predictive value of MDCT for the detection of significant CABG stenoses were 91.4%, 98.5%, 84.2%, and 99.2%, respectively. Including nonevaluable segments in the analysis, overall sensitivity was 84.2%. For the evaluation of native coronary arteries, MDCT had a sensitivity of 82.1% and a specificity of 75.3%, but evaluability was only 71.2%, resulting in overall sensitivity of 62.1%.

CONCLUSION

Use of 16-slice MDCT angiography allows very accurate evaluation of CABG patency and has high diagnostic accuracy in detecting graft stenoses. But evaluation of native coronary artery stenosis is limited, particularly in patients with advanced coronary artery disease with severe calcification.

Inferior mesenteric arteriovenous fistula with ischemic colitis: multidetector computed tomographic angiography for diagnosis

Inferior mesenteric arteriovenous fistula is rare and may be congenital or acquired. Two serious manifestations may occur in the course of the disease: portal hypertension and bowel ischemia. The diagnosis is generally established by conventional angiography. In this report, we present a case with multiple inferior mesenteric arteriovenous fistulas, considered idiopathic due to no known cause related to the etiology, and associated ischemic colitis, which were clearly demonstrated by multidetector computed tomographic angiography. We also review the available literature.

Multidetector computed tomographic angiography of aberrant subclavian arteries

Abstract

The purpose of this study was to evaluate the utility of 16-slice multidetector computed tomographic (MDCT) angiography for identifying anatomic features of aberrant subclavian arteries. Seventeen patients with aberrant subclavian arteries were assessed by MDCT angiography. The aortic arch position, the presence of a Kommerell’s diverticulum, aneurysm, vascular compression of trachea and oesophagus and associated cardiovascular abnormalities were evaluated. MDCT findings were confirmed by surgery in eight patients but in the other nine patients no further evaluation or management was warranted as the aberrant subclavian artery had no significant clinical consequence. Eleven patients had an aberrant right subclavian artery arising from the left aortic arch and six patients had an aberrant left subclavian artery arising from the right aortic arch. Kommerell’s diverticulum was identified in three patients with an aberrant right subclavian artery and in five patients with an aberrant left subclavian artery. In two patients it was aneurysmal. Oesophageal compression was detected in eight patients, and tracheal compression was identified in only one paediatric patient. An aberrant subclavian artery was associated with complex congenital heart disease in one patient, intracardiac defects in two patients, aortic coarctation in two patients, patent ductus arteriosus in two patients and an aberrant vertebral artery in one patient. In conclusion, MDCT angiography is superior to digital subtraction angiography for the assessment of aberrant subclavian arteries since digital subtraction angiography has only a poor ability to visualize adjacent structures completely and is invasive in nature. MDCT angiography or magnetic resonance angiography are the current standard in the initial evaluation of thoracic vascular anomalies.

Clinical value of 16-slice multidetector computed tomography in symptomatic patients with suspected coronary artery disease

BACKGROUND

Multidetector computed tomography angiography has emerged as a rapidly developing method for the noninvasive detection of coronary artery disease.

PURPOSE

To investigate the diagnostic accuracy and limitations of multidetector computed tomography (MDCT) in the detection of significantly (> 50%) obstructive coronary artery disease (CAD) using a scanner equipped with 16 x 0.625-mm collimation.

MATERIAL AND METHODS

MDCT angiography was performed in 153 patients (99 male, 54 female; mean age 55 +/- 10 years) with suspected CAD and scheduled for conventional coronary angiography (CCA). Image quality was assessed in terms of artifacts and segment visibility, and the assessable segments were screened for the presence of significant stenoses (> 50% lumen diameter reduction). The diagnostic performance of MDCT for the detection of significant stenosis was compared with the results of CCA.

RESULTS

In all 153 patients, MDCT was carried out without complications. A total of 1989 coronary artery segments were evaluated. After exclusion of 394 non-evaluable segments (19.8%), 1595 segments (80.2%) were included in the analysis. The most frequent causes of poorly assessable segments were motion artifact (36%) and severe calcification (23%). Considering only the segments judged to be evaluable, the sensitivity, specificity, and positive and negative predictive values of 16-slice MDCT were 85%, 97%, 79%, and 98%, respectively. Including all segments in the analysis (evaluable and non-evaluable), the sensitivity was 74%, specificity 96%, positive predictive value 73%, and negative predictive value 97%.

CONCLUSION

When all coronary artery segments are included, 16-slice MDCT has moderate sensitivity and very high specificity and negative predictive value in assessing coronary artery stenoses. High specificity and negative predictive value indicate that 16-slice MDCT may be a useful tool in reliably ruling out significant lesions in patients with a low pretest probability.

Cake kidney: MDCT urography for diagnosis

Cake (fused pelvic) kidney is an uncommon congenital anomaly. Early diagnosis and recognition of potential complications that may accompany this anomaly are important to prevent permanent renal impairment. To the best of our knowledge, this is the first report on a case of cake kidney that was diagnosed by multidetector row computed tomographic urography.