Use Of MDCT Research Articles

MDCT EVALUATION OF AORTIC ROOT AND ASCENDING AORTIC PATHOLOGIES: PICTORIAL ESSAY

Objective; The purpose of this pictorial essay is to review the MDCT appearance of aortic root and ascending aortic pathologies. Familiarity with atypical anatomy and pathologies of the aortic root, ascending aorta and their clinical presentation may facilitate appropriate diagnosis and management.This can be of immense help to the clinician planning interventional procedures such as stenting, balloon dilatation, or graft surgery. Conclusion; Increasing use of MDCT for cardiac imaging has helped in the detection of many benign aortic root anomalies, but a small number are associated with myocardial ischemia and sudden death. Increasing the use of MDCT in cardiac imaging may yield diagnostic information on pathologies of the aortic root and ascending aorta not obtained with invasive coronary angiography. Axial sections, multiplanar reconstructions, virtual angioscopy, and 3D volume-rendered images should aid in the detection and improve the interpretation of such pathologies.

Imaging of blunt bowel and mesenteric injuries: Current status

Blunt abdominal trauma often presents a diagnostic challenge. Clinical examination demonstrates low reliability in detecting abdominal injury (16 %) when there is a history of head injury or loss of consciousness. This can prove detrimental, as delays in the diagnosis of traumatic bowel injury of 8 h or less can result in increased morbidity and mortality, as well as prolonged hospitalization. Although hemodynamically unstable patients will require an urgent laparotomy following clinical assessment, MDCT is the modality of choice for comprehensive imaging of blunt abdominal trauma in hemodynamically stable patients. Despite the use of MDCT, blunt injury to the bowel and mesentery, which accounts for up to 5% of injuries in cases of trauma, may be difficult to detect. The use of a constellation of direct and indirect signs on MDCT can help make the diagnosis and guide clinical management. Direct signs on MDCT, such as bowel wall discontinuity, and extraluminal gas may assist in the diagnosis of traumatic bowel injury. However, these signs are not sensitive. Therefore, the astute radiologist may have to rely on indirect signs of injury, such as free fluid, bowel wall thickening, and abnormal bowel wall enhancement to make the diagnosis. This review will focus on MDCT imaging findings of bowel and mesenteric injuries secondary to blunt abdominal trauma.

Impact of intra-peritoneal fat distribution on intra-operative bleeding volume with D2 lymphadenectomy in Chinese patients with gastric cancer

To explore the quantitative measurements and evaluation of intra-peritoneal fat distribution by MDCT and its significance in predicting intra-operative bleeding volume during D2 lymphadenectomy in gastric cancer (GC) patients. From June 2016 to September 2017, GC patients scheduled for open gastrectomy with D2 lymph-node dissection were enrolled. According to the BMI, the subjects were then classified as normal BMI(BMI<25kg/m2); overweight (BMI=25-30 kg/m2) and obese (BMI≥30kg/m2). According to the intraoperative blood loss (IBL), the patients were further separated into high IBL (IBL; ≥ 300ml) or low IBL (<300ml). Clinicopathological parameters between the groups were statistically compared and univariate and multivariate analysis were used to identify predictive factors such as intra-peritoneal fat areas (IFA) and intra-peritoneal fat areas ratio (IFAR) for high IBL. A total of 226 patients were included in the study where 53 patients underwent distal while 173 underwent total gastrectomy. According to the BMI classification, there were 25 normal BMI, 108 overweight and 25 obese subjects. According to the IBL, there were 98 high IBL and 128 low IBL subjects. IFA and IFAR were significantly greater in the high IBL group than in the low IBL group. There was no significant difference in any other clinicopathological factors between the high IBL group and the low IBL group. Multivariate analysis revealed that high IFA and IFAR independently predicted high IBL. The use of MDCT to evaluate the precise distribution of abdominal fat during preoperative examination can prompt surgeons to develop techniques to decrease intraoperative bleeding in obese patients. Nevertheless, it is yet necessary to be surgically more meticulous when dealing with patients with high IFA or high IFA/IFAR in order to improve the outcome of D2 gastrectomy.

Diagnostic Performance of Multidetector Computerized Tomography in the Detection of Abdominal Complications Early and Late After Liver Transplantation: A 10-Year Experience

BackgroundMultidetector computerized tomography (MDCT) is considered to be a fast noninvasive diagnostic technique for the evaluation of postoperative complications in patients with liver transplantation (LT). However, its role has not been fully established in the diagnosis for detecting complications after liver transplantation. The aim of this work was to evaluate the diagnostic performance of MDCT for detecting abdominal complications in the early and late periods after LT. MethodsWe retrospectively enrolled 75 patients who had undergone LT from March 2006 to January 2010, followed by MDCT from March 2006 to November 2017. Patients were divided into 2 groups according to the timing after LT: within the first 3 months (early period) or ≥3 months after LT (late period). We evaluated vascular, biliary, and other complications on MDCT. Angiography, endoscopic retrograde cholangiography, and percutaneous transhepatic cholangiography were used as reference standards. ResultsWe initially found 77 complications in 45 patients (60.0%) with the use of MDCT. After comparison with the reference standards, 83 complications were diagnosed in 49 patients (65.3%). Forty-seven complications (34 vascular, 10 biliary, 3 other complications) were diagnosed in 33 patients (44.0%) during the early period, and 36 complications (6 vascular, 20 biliary, 10 other complications) were detected in 27 patients (36.0%) in the late period. The sensitivity, specificity, and diagnostic accuracy of MDCT for diagnosing overall complications were, respectively, 93.6%, 90.2%, and 92.0% in the early period (for vascular complications: 97.1%, 92.6%, and 94.3%,; for biliary complications: 80.0%, 100%, and 97.7%) and 77.8%, 98.1%, and 89.8% in the late period (for vascular complications: 83.3%, 100%, and 98.9%; for biliary complications: 65.0%, 98.6%, and 90.9%). ConclusionsAlthough MDCT in the late period should be interpreted with caution in patients with suspected biliary complication, MDCT is a reliable diagnostic technique for the identification of early and late abdominal complications after LT.

Use of MDCT to Assess the Results of Bronchial Thermoplasty.

The purpose of this study was to evaluate the use of MDCT to assess response to bronchial thermoplasty treatment for severe persistent asthma. MDCT data from 26 patients with severe persistent asthma who underwent imaging before and after bronchial thermoplasty were analyzed retrospectively. Changes in the following parameters were assessed: total lung volume, mean lung density, airway wall thickness, CT air trapping index (attenuation < -856 HU), and expiratory-inspiratory ratio of mean lung density (E/I index). Asthma Quality of Life Questionnaire score changes were also assessed. Median total lung volumes before and after bronchial thermoplasty were 2668 mL (range, 2226-3096 mL) and 2399 mL (range, 1964-2802 mL; p = 0.08), respectively. Patients also showed a pattern of obstruction improvement in air trapping values (median before thermoplasty, 14.25%; median after thermoplasty, 3.65%; p < 0.001] and in mean lung density values ± SD (before thermoplasty, -702 ± 72 HU; after thermoplasty, -655 ± 66 HU; p < 0.01). Median airway wall thickness also decreased after bronchial thermoplasty (before thermoplasty, 1.5 mm; after thermoplasty, 1.1 mm; p < 0.05). There was a mean Asthma Quality of Life Questionnaire overall score change of 1.00 ± 1.35 (p < 0.001), indicating asthma clinical improvement. Our study showed improvement in CT measurements after bronchial thermoplasty, along with Asthma Quality of Life Questionnaire score changes. Thus, MDCT could be useful for imaging evaluation of patients undergoing this treatment.

Management of the Incidental Pulmonary Embolism.

The incidental pulmonary embolism (PE) is being identified at an increasing rate because of use of MDCT and presents a management challenge because of a lack of prospective data. Most clinicians treat patients with proximal or segmental incidental PE in the same manner as patients with suspected PE. The treatment of subsegmental PE may be guided by an assessment of patient symptoms, risk factors for recurrent venous thrombosis, and concomitant deep venous thrombosis.

Usefulness of MDCT to Differentiate Between Renal Cell Carcinoma and Oncocytoma: Development of a Predictive Model.

The objective of our study was to identify the most useful parameters to differentiate between renal cell carcinoma (RCC) and oncocytoma using four-phase CT. Ninety-seven patients with solid renal lesions who underwent surgery with four-phase preoperative CT evaluation and with pathologic diagnosis of RCC or oncocytoma were included in the study. Features of tumors and the enhancement pattern in the four CT phases were evaluated and analyzed. Logistic regression models were used to assess independent predictors for malignancy. Histopathologically, 13 tumors were oncocytomas and 84 were RCCs. RCCs were larger (6.20 cm vs 3.21 cm, p = 0.0004) and more often enhanced heterogeneously (66 vs 6, p = 0.02). Lesions that were larger than 4 cm showed a significantly higher risk of malignancy (p = 0.0046). Significant differences were found in intensity of nodule enhancement between the nephrographic and the excretory phases with respect to the unenhanced phase (p = 0.003 and p = 0.0026). At multivariate analysis, parameters that were independent predictors of malignancy were enhancement pattern, with RCCs more often having heterogeneous enhancement than oncocytomas (odds ratio [OR], 0.18; 95% CI, 0.04-0.90), and nodule enhancement in the excretory phase in relation to the unenhanced phase, with RCCs showing lower enhancement (OR, 0.93; 95% CI, 0.88-0.97), and a size larger than 4 cm (OR, 4.01; 95% CI, 0.70-23.14). The combination of different CT parameters including lesion size larger than 4 cm, lesion enhancement in the excretory phase in relation to the unenhanced phase, and heterogeneous enhancement pattern helps distinguish RCC from oncocytoma.

Use of MDCT to Differentiate Autoimmune Pancreatitis From Ductal Adenocarcinoma and Interstitial Pancreatitis.

The purposes of this study were to identify the most common imaging features of autoimmune pancreatitis and to evaluate the utility of MDCT for differentiating autoimmune pancreatitis from two more frequently encountered differential diagnoses--pancreatic ductal adenocarcinoma and acute interstitial pancreatitis. Dual-phase contrast-enhanced MDCT images of 91 patients (39 with autoimmune pancreatitis, 25 with pancreatic ductal adenocarcinoma, 27 with acute interstitial pancreatitis) were evaluated by two radiologists in consensus for distribution of pancreatic abnormality, sausage shape, low-attenuation halo, pancreatic duct dilatation, peripancreatic stranding, lymphadenopathy, biliary abnormality, vascular involvement, and renal lesions. Chi-square tests, multiple logistic regression analysis, and ROC analysis were performed. The most common imaging features of autoimmune pancreatitis were sausage shape (25/39 [64%]) and low-attenuation halo (23/39 [59%]). Pancreatic duct dilatation (20/25 [80%]) and biliary dilatation (11/25 [44%]) were most frequent in pancreatic ductal adenocarcinoma. Peripancreatic stranding (22/27 [81%]) was most frequent in acute interstitial pancreatitis. Sausage shape, low-attenuation halo, and absence of a pancreatic duct or biliary dilatation differentiated autoimmune pancreatitis from pancreatic ductal adenocarcinoma with an accuracy of 0.88. Sausage shape and absence of peripancreatic stranding differentiated autoimmune pancreatitis from acute interstitial pancreatitis with an accuracy of 0.82. There was no significant difference in the frequency of vascular involvement or of lymphadenopathy among these diagnoses. Typical cases of autoimmune pancreatitis can be accurately differentiated from pancreatic ductal adenocarcinoma and acute interstitial pancreatitis on the basis of characteristic MDCT features. However, autoimmune pancreatitis should be considered in the presence of atypical features.

Multi-detector computed tomography assessment of the tibial plateau fractures

ObjectiveThe purpose of our study was to assess the role of multi-detector CT in the evaluation of tibial plateau fractures. Subjects and methodsThe study included twenty patients with fractures of the tibial plateau shown on computed tomographic images. All patients subjected to non-contrast MDCT in axial cuts and images are transferred to workstation; then they underwent coronal, sagittal reconstructed images and 3-D volume rendering that are of benefit in final diagnosis. ResultsA total of 20 patients were included (their mean age 27years). It was found that the most common type is type II according to Schatzker classification, followed by type I. ConclusionThe use of MDCT is advised for the accurate classification of tibial plateau fractures and so the management decision.

The role of multidetector computed tomography and magnetic resonance recent imaging techniques in the evaluation of intra-conal orbital lesions

ObjectiveThe purpose of our study was to assess the role of multi-detector computed tomography and magnetic resonance recent imaging techniques in the evaluation of intra-conal orbital lesions. Subjects and methods30 patients presented to the Ophthalmic and Radiology Departments at El-Minia University Hospital and El Minia Oncology Center with clinical diagnosis of visual loss and proptosis. They presented during the period from June 2012 to October 2013. Their ages range from 5 to 73years. All patients subjected to MDCT and MRI. Also, contrast injection was injected on some cases. 24 patients were subjected to surgery and histopathology to confirm the radiological diagnosis. ResultsA total of 30 patients were included (their mean age 26years). 8 lesions were diagnosed inflammatory in nature (4 were orbital abscess and 4 were idiopathic orbital inflammatory disease i.e. pseudo tumors). 10 lesions were diagnosed as vascular lesions (2 lesions were carotid cavernous fistula and 8 lesions were cavernous hemangiomas). 6 lesions were diagnosed as optic nerve gliomas and other 6 lesions were diagnosed optic nerve sheath meningiomas. ConclusionThe use of MDCT and MRI recent techniques are mandatory for accurate diagnosis of the nature of intra-conal orbital mass lesions.

Role of CT and MRCP in Evaluation of Biliary Tract Obstruction

Obstructive jaundice which is caused by bile duct obstruction can be clinically and biochemically indistinguishable from cholestatic jaundice caused by hepatocellular disease. The management of both these conditions being radically different, the principle task of the radiologist is to differentiate between hepatocellular and obstructive jaundice, using available imaging modality and help in further management. With the availability of non-invasive modality like computed tomography and magnetic resonance imaging (MRI), it is possible to diagnose obstructive jaundice early and accurately without any patient discomfort. The purpose of this article is to describe the protocol for evaluation of obstructive jaundice with use of MDCT and magnetic resonance cholangio pancreatography sequence of MRI and to describe the imaging features of the most common causes of obstructive jaundice like biliary calculi, bile duct strictures, choledochal cyst, gall bladder carcinoma, cholangiocarcinoma, primary sclerosing cholangitis, and pancreatic head carcinoma.

The role of multi detector computerized tomography in evaluation of maxillofacial fractures

ObjectiveThe purpose of our study was to assess the role of multi-detector CT in the evaluation of maxillofacial fractures. Subjects and methodsThe study included 30 patients complaining from facial trauma with suspected facial fractures referred from the emergency unit of the El-Minia University Hospital. All patients subjected to non contrast MDCT in axial cuts and images are transferred to workstation then they underwent coronal, sagittal reconstructed images and 3-D volume rendering that are of benefit in final diagnosis. ResultsA total of 30 patients were included (their mean age 26years). It was found that the nasal bone is most common to be fractured (found in 19 cases), followed by maxillary bone (17 cases), zygomatic bone (10 cases), mandibular bone (8 cases) and the pterygoid plates are least frequent to be fractured (6 cases). Also, concerning the complex facial fractures; the orbital wall fractures are the most frequent (found in 22 cases), followed by zygomatico-maxillary complex fractures (8 cases), the naso-orbito-ethmoid fractures (6 cases), and lastly comes the Le Forte fractures (found in 4 cases). ConclusionThe use of MDCT is mandatory for the accurate classification of maxillo-facial fractures and so the management decision.

Multilevel Assessment of Atherosclerotic Extent Using a 40-Section Multidetector Scanner after Transient Ischemic Attack or Ischemic Stroke

The first part of this study assessed the potential of MDCT with a CTA examination of the aorta and the coronary, cervical, and intracranial vessels in the etiologic work-up of TIA or ischemic stroke compared with established imaging methods. The objective of the second part of this study was to assess the atherosclerotic extent by use of MDCT in these patients. From August 2007 to August 2011, a total of 96 patients with ischemic stroke or TIA without an evident cardioembolic source were enrolled. All patients underwent MDCT. Atherosclerotic extent was classified in 0, 1, 2, 3, and 4 atherosclerotic levels according to the number of arterial territories (aortic arch, coronary, cervical, intracranial) affected by atherosclerosis defined as ≥ 50% cervical, intracranial, or coronary stenosis or ≥ 4-mm aortic arch plaque. There were 91 patients who had an interpretable MDCT. Mean age was 67.4 years (± 11 years), and 75 patients (83.3%) were men. The prevalence of 0, 1, 2, 3, and 4 atherosclerotic levels was 48.3%, 35.2%, 12.1%, 4.4%, and 0%, respectively. Aortic arch atheroma was found in 47.6% of patients with 1 atherosclerotic level. The combination of aortic arch atheroma and cervical stenosis was found in 63.6% of patients with ≥ 2 atherosclerotic levels. Patients with ≥ 2 atherosclerotic levels were older than patients with < 2 atherosclerotic levels (P = .04) in univariate analysis. MDCT might be useful to assess the extent of atherosclerosis. It could help to screen for high-risk patients who could benefit from a more aggressive preventive strategy.

Accuracy of MDCT in the preoperative definition of Peritoneal Cancer Index (PCI) in patients with advanced ovarian cancer who underwent peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC)

To evaluate the accuracy of MDCT in the preoperative definition of Peritoneal Cancer Index (PCI) in patients with advanced ovarian cancer who underwent a peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC) after neoadjuvant chemotherapy to obtain a pre-surgery prognostic evaluation and a prediction of optimal cytoreduction surgery. Pre-HIPEC CT examinations of 43 patients with advanced ovarian cancer after neoadjuvant chemotherapy were analyzed by two radiologists. The PCI was scored according to the Sugarbaker classification, based on lesion size and distribution. The results were compared with macroscopic and histologic data after peritonectomy and HIPEC. To evaluate the accuracy of MDCT to detect and localize peritoneal carcinomatosis, both patient-level and regional-level analyses were conducted. A correlation between PCI CT and histologic values for each patient was searched according to the PCI grading. Considering the patient-level analysis, CT shows a sensitivity, specificity, PPV, NPV, and an accuracy in detecting the peritoneal carcinomatosis of 100 %, 40 %, 93 % 100 %, and 93 %, respectively. Considering the regional level analysis, a sensitivity, specificity, PPV, NPV, and diagnostic accuracy of 72 %, 80 %, 66 %, 84 %, and 77 %, respectively were obtained for the correlation between CT and histology. Our results encourage the use of MDCT as the only technique sufficient to select patients with peritoneal carcinomatosis for cytoreductive surgery and HIPEC on the condition that a CT examination will be performed using a dedicated protocol optimized to detect minimal peritoneal disease and CT images will be analyzed by an experienced reader.

Fracture Mimics on Temporal Bone CT: A Guide for the Radiologist

The objective of this article is to discuss and illustrate commonly visualized fissures and sutures in the temporal bone. This topic is important because a thorough knowledge of normal anatomy is necessary to avoid misinterpretation as fractures. Small normal anatomic fissures are now routinely visualized with the increasing use of MDCT in trauma patients. An awareness of these structures is required by radiologists interpreting studies with fine temporal bone slices to prevent erroneous interpretation.

Clinical role of radiography for thoracic spine fractures in daily practice in the MDCT era: a retrospective review of 255 trauma patients

To retrospectively assess the diagnostic efficacy of radiography in detecting vertebral body fractures of the thoracic spine compared with MDCT, to assess the confounding factors reducing the diagnostic efficacy, and to investigate the outcomes of radiographically overlooked patients. Two hundred fifty-five patients suspected of thoracic spine fractures were enrolled. We assessed the diagnostic efficacy of radiography for the patients sub-grouped based on five confounding factors: chest abnormalities, head injuries, cervical spine fractures, upper extremity injuries, and age of 65 years or older. We investigated the outcomes of radiographically overlooked patients. Three hundred fifty-one vertebral body fractures were detected. The per-fracture sensitivities and specificities were 55 % and 94 % for vertebral body fractures and 41 and 99 % for unstable fractures. In patients with upper extremity injuries or aged 65 years or older, radiography was less sensitive in detecting the unstable fractures (P < 0.05). Nineteen patients were overlooked by radiography; two had neurological deficits and needed surgical fixation; 15 with no neurological deficit were conservatively treated with uneventful outcomes. Radiography had low sensitivity but high specificity. In daily practice, primary use of MDCT is beneficial for patients with neurological deficit or upper extremity injuries or elderly patients.

Cor triatriatum sinister versus bowed septum primum in an infant with total anomalous pulmonary venous connection: a difficult imaging distinction

In cor triatriatum sinister, a membrane divides the left atrium into a posterior chamber that receives the pulmonary veins and an anterior chamber that communicates with the mitral valve. With right-side chamber overload, the septum primum can separate from the muscular septum and bow toward the left atrial cavity, leading to a thin membrane within the left atrium and imaging findings that may mimic cor triatriatum. We report the multidetector CT findings of a 3-month-old infant with a supracardiac total anomalous pulmonary venous connection with a bowed septum primum. A description of the imaging findings that distinguish cor triatriatum and bowed septum primum will be discussed. This case demonstrates the usefulness of MDCT in the assessment of supracardiac vascular anomalies and intracardiac anatomy.

Catheter-Induced Aortic Dissection After Invasive Coronary Angiography: Evaluation With MDCT

The purpose of this study was to describe the MDCT findings of retrograde aortic extension of catheter-induced coronary artery dissection and the use of MDCT in follow-up of this complication. Coronary artery dissection with aortic extension can be a fatal although infrequent complication. The coronary artery entry point is usually stented in the catheterization laboratory. Thereafter, CT is the imaging modality of choice for immediate confirmation of the presence of residual iatrogenic aortic dissection and evaluation of its extent and later noninvasive follow-up.

Multidetector computed tomography evaluation of bony fragments and donor sites in acute patellar dislocation

Patellar dislocation is frequently associated with bony fragments that are difficult to see on radiographs. MRI or MDCT are often used to rule out or characterize these bony fragments. To assess the use of MDCT for locating bony fragments and donor sites in patients with acute patellar dislocation, and to test whether sizes and quantity of bony fragments differ between first-time dislocations and recurrent dislocations. Retrospective data from two hospitals during a 96-month period were collected, and a total of 46 patients (mean age 27 years, range 9-69 years) that had sustained an acute patellar dislocation (22 first-time, 24 recurrent) were identified. Size, location and donor site of bony fragments were evaluated on MDCT images. Surgical correlation was available for 22 of 46 patients. On MDCT images, the likely donor site could be identified in 62 of 71 (87%) bony fragments. Of the bony fragments that were seen on MDCT images, 40 of 68 (59%) were not seen on AP and lateral views of the conventional radiographs. There was no significant difference in size of bony fragments between first-time or recurrent dislocators (p=0.77). The average number of bony fragments were 2.1 and 1.0 in first-time and recurrent dislocators, respectively. The location and donor site of bony fragments was similar between two patients groups. MDCT is a suitable imaging method to locate bony fragments and donor sites. The number of bony fragments seems to be higher in first-time dislocators than recurrent dislocators, otherwise findings between the two patient groups were similar.

Usefulness of MDCT Guided Mitral Isthmus Ablation

Mitral isthmus (MI) ablation is challenging. Blood flow in the CS and circumflex artery (LCx) may act as a heat sink and reduce the efficacy of radiofrequency ablation. Ablation in the CS also has the risk of injury to the LCx. We have reported to be able to visualize the precise anatomical characteristics between CS and LCx on MI obtained by MDCT. The aim of this study was to evaluate usefulness of MDCT guided MI ablation. Methods: Twenty patients (14 males, 61±11 y) whose CS and LCx images could be obtained simultaneously by MDCT were included in this study. We performed MI ablation between LIPV and the mitral annulus. The strategy for MDCT guided MI ablation were 1. MI line was designed just below LAA, 2. In case of LCx below CS, MI line was designed proximal the crossing point of LCX and CS, and 3. If LCX is presence on MI, MI line designed more laterally on comparatively peripheral LCX. Irrigated-tip catheters were used during MI ablation with the following settings: endocardial surface (maximum power: 40 W); CS (maximum power: 20 W). Results: The MI was blocked in 94.5% (19/20) of patients with 594±293 seconds of radiofrequency application. The epicardial ablation inside the CS was required in 45% (9/20) patients. No complications occurred. Conclusion: The MDCT guided MI ablation resulted in a high success rate of MI block without complications.