Calcium score: semiautomatic calculation using different vendors versus fully automatic software.

OBJECTIVES: Recent advances in technology have resulted in a multitude of cardiac imaging postprocessing software products from vendors unrelated to the scanner on which the cardiac study was initially performed. A fully automatic calcium score software has also become available. We assess the intervendor variability of calcium score measurement using the semiautomatic software provided by the scanner vendor versus an unrelated vendor versus fully automatic software. METHODS: All consecutive patients who had a calcium score performed from March 2007 to January 2008 were included in this study. The studies were performed on two 64-slice computed tomographic scanners from 2 different vendors. The allocation of the patient to the specific scanner was done according to scanner and technologist availability. The studies were read twice by a cardiac radiologist and a general radiologist with at least 3 months' interval at a workstation specified by the computed tomographic scanner vendor and then at an unrelated workstation, with semiautomatic software. Calcium score was also independently performed by the fully automatic software, blinded to the results of previous readings. Agreement was tested with Pearson correlation coefficient, Bland-Altman graphs, and the Fleiss κ test. RESULTS: The study population included 101 patients: 70 patients scanned at 1 scanner and 31 at a different scanner. Intervendor variability for the 2 groups had κ = 0.98 ± 0.01 and κ = 0.96 ± 0.02; interobserver variability had κ = 1. Semiautomatic versus automatic variability showed κ = 0.88 to 0.94. CONCLUSIONS: Because of very strong agreement between the calcium score measurements obtained by semiautomatic and fully automatic software by different vendors, calcium score measurements can be performed robustly at vendor-specific software, nonrelated software, or fully automatic software.

Management of combat vascular injuries using modern imaging: are we getting better?

Background. Vascular injuries often result in life threatening hemorrhage or limb loss. When they present with a single entry or exit wound, surgery is immediately indicated. With multiple injuries, however, imaging such as CTA is necessary for diagnosis and choice of treatment. Methods. For all combat-related vascular cases admitted to our medical center during the Lebanon wars in 1982 and 2006, we compiled and compared presenting signs and symptoms, means of diagnosis, treatments, and results. Results. 126 patients with vascular injuries were admitted (87 in 1982, 39 in 2006). 90% were male; mean age of 29 years (range 20-53). All injuries were accompanied by insult to soft tissue, bones, and viscera. 75% presented with injury to arteries in the extremities. 75% of these patients presented with limb ischemia, and 25% sustained massive blood loss. Treatments included venous interposition graft, end-to-end anastomosis, venous patch, endovascular technique (only in 2006), and ligation/observation. Complications included thrombosis and wound infections. Mortality and amputations occurred only in 1982, and this may be attributed to the use of imaging, advanced technique, and shorter average time from injury to hospital (7 hours). Conclusions. We recommend CTA as the first line modality for diagnosis of vascular injuries, as its liberal use allowed for early and appropriate treatment. Treatment outcomes improved with fast and effective resuscitation, liberal use of tourniquets and fasciotomies, and meticulous treatment by a multidisciplinary team.

Deep sedation during pneumatic reduction of intussusception.

BACKGROUND: Pneumatic reduction of intussusception under fluoroscopic guidance is a routine procedure. The unsedated child may resist the procedure, which may lengthen its duration and increase the radiation dose. We use deep sedation during the procedure to overcome these difficulties. OBJECTIVE: The purpose of this study was to summarize our experience with deep sedation during fluoroscopic reduction of intussusception and assess the added value and complication rate of deep sedation. MATERIALS AND METHODS: All children with intussusception who underwent pneumatic reduction in our hospital between January 2004 and June 2011 were included in this retrospective study. Anesthetists sedated the children using propofol. The fluoroscopic studies, ultrasound (US) studies and the childrens' charts were reviewed. RESULTS: One hundred thirty-one attempted reductions were performed in 119 children, of which 121 (92%) were successful and 10 (8%) failed. Two perforations (1.5%) occurred during attempted reduction. Average fluoroscopic time was 1.5 minutes. No complication to sedation was recorded. CONCLUSIONS: Deep sedation with propofol did not add any complication to the pneumatic reduction. The fluoroscopic time was short. The success rate of reduction was high,raising the possibility that sedation is beneficial, possibly by smooth muscle relaxation.

Last fluoroscopy hold in paediatric fluoroscopy: dynamic capture of physiological events and a potential for radiation exposure time reduction.

The purpose of this study was to retrospectively evaluate last fluoroscopy hold (LFH) in paediatric fluoroscopy. LFH is a software program that enables dynamic storage of last fluoroscopy sequences. A hundred and ninety-four paediatric patients underwent 215 fluoroscopy examinations during a 14-month period. LFH was employed to review an equivocal finding, when last image hold did not provide an adequate diagnostic image or when a physiologic dynamic event was too fast or did not last long enough to capture. LFH was used in 29% of the examinations. The Institutional Review Board approved this study and waived informed consent.

CT multiplanar reconstructions (MPR) for shrapnel injury trajectory.

We report our experience in implementing CT multiplanar reformats (MPRs) to demonstrate the trajectory of penetrating trauma. It is an easily learned tool that can be conveniently and speedily applied in the fragments injury. We describe the detailed technique of performing MPRs, depicted by various examples. Furthermore, benefits and limitations of the technique (such as numerous fragments, change in position and respiratory phase, and embolization of fragments) are presented. We conclude that MPRs in the fragments trajectory can be helpful for accurate and fast diagnosis of injury. In addition, MPRs serve as a vivid presentation of injured and spared organs.

Arterial air emboli on computed tomography (CT) autopsy.

OBJECTIVE: To describe radiological appearances of systemic air emboli versus intravascular air from putrefaction. MATERIALS AND METHODS: The hospital trauma database was searched for patients who underwent computed tomography (CT) autopsy. The studies were reviewed and evaluated for intravascular gas. The appearances and location of intravascular air were characterised. RESULTS: Four cases of intravascular gas were identified out of 15 cases of CT autopsy performed from March 2004 to December 2006. In three cases, intravascular air was predominantly in the arterial system, coupled with severe pulmonary injury. In one case, the air was predominantly in the venous system with a large amount of gas in portal veins. CONCLUSION: We propose to consider pulmonary alveoli-venous fistula as a possible cause of systemic air emboli, as identified on CT autopsy by large amounts of gas in the arterial circulation, coupled with severe pulmonary injury.

Integrated SPECT/CT for assessment of haemodynamically significant coronary artery lesions in patients with acute coronary syndrome.

PURPOSE: Early risk stratification in patients with non-ST elevation acute coronary syndromes (NSTE-ACS) is important since the benefit from more aggressive and costly treatment strategies is proportional to the risk of adverse clinical events. In the present study we assessed whether hybrid single photon emission computed tomography (SPECT)/coronary computed tomography angiography (CCTA) technology could be an appropriate tool in stratifying patients with NSTE-ACS. METHODS: SPECT/CCTA was performed in 90 consecutive patients with NSTE-ACS. The Thrombolysis in Myocardial Infarction risk score (TIMI-RS) was used to classify patients as low- or high-risk. Imaging was performed using SPECT/CCTA to identify haemodynamically significant lesions defined as >50% stenosis on CCTA with a reversible perfusion defect on SPECT in the corresponding territory. RESULTS: CCTA demonstrated at least one lesion with >50% stenosis in 35 of 40 high-risk patients (87%) as compared to 14 of 50 low-risk patients (35%; TIMI-RS<3; p<.0001). Of the 40 high-risk and 50 (16%) low-risk TIMI-RS patients, 16 (40%) and 8 (16%), respectively, had haemodynamically significant lesions (p=0.01). Patients defined as high-risk by a high TIMI-RS, a positive CCTA scan or both (n=45) resulted in a sensitivity of 95%, specificity of 49%, PPV of 35% and NPV of 97% for having haemodynamically significant coronary lesions. Those with normal perfusion were spared revascularization procedures, regardless of their TIMI-RS. CONCLUSION: Noninvasive assessment of coronary artery disease by SPECT/CCTA may play an important role in risk stratification of patients with NSTE-ACS by better identifying the subgroup requiring intervention.

Classification of breast cancer precursors through exhaled breath.

Certain benign breast diseases are considered to be precursors of invasive breast cancer. Currently available techniques for diagnosing benign breast conditions lack accuracy. The purpose of this study was to deliver a proof-of-concept for a novel method that is based on breath testing to identify breast cancer precursors. Within this context, the authors explored the possibility of using exhaled alveolar breath to identify and distinguish between benign breast conditions, malignant lesions, and healthy states, using a small-scale, case-controlled, cross-sectional clinical trial. Breath samples were collected from 36 volunteers and were analyzed using a tailor-made nanoscale artificial NOSE (NA-NOSE). The NA-NOSE signals were analyzed using two independent methods: (i) principal component analysis, ANOVA and Student's t-test and (ii) support vector machine analysis to detect statistically significant differences between the sub-populations. The NA-NOSE could distinguish between all studied test populations. Breath testing with a NA-NOSE holds future potential as a cost-effective, fast, and reliable diagnostic test for breast cancer risk factors and precursors, with possible future potential as screening method.

Low infection rates and prolonged survival times of hemodialysis catheters in infants and children.

BACKGROUND AND OBJECTIVES: Hemodialysis (HD) catheter-related complications are regarded as the main cause of HD failure in infants and children with ESRD. In this study, we determined HD catheter infection rates and survival times in children. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We analyzed demographic, clinical, laboratory, and microbiologic data on all infants and children with ESRD who received HD therapy through a tunneled central venous catheter (CVC) in our Pediatric Dialysis Unit between January 2001 and December 2009. Our strict care of HD-CVCs makes no use of any kind of prophylactic antibiotic therapy. RESULTS: Twenty-nine children with ESRD (median age, 10 years) received HD through a CVC, for a total of 22,892 days during the study period. Eleven (38%) children were infants (<1 year of age) who received HD for a cumulative 3779 days (16% of total). Fifty-nine CVCs were inserted, of which 13 (22%) were in infants. There were 12 episodes of CVC infection-a rate of 0.52/1000 CVC days. Four (33%) episodes occurred in infants-a rate of 1.06/1000 CVC days. Only three (5%) of the CVCs were removed because of infection. Median catheter survival time for all children was 310 days and for infants was 211 days. CONCLUSIONS: Very low CVC infection rates (one infection per 5 CVC years) and prolonged CVC survival times (around 1 year) are achievable in infants and children with ESRD receiving HD therapy by adhering to a strict catheter management protocol and without using prophylactic antibiotic therapy.

Vascular injuries in an urban combat setting: experience from the 2006 Lebanon war.

UNLABELLED: Vascular injuries are manifested by life-threatening hemorrhage or limb loss and their diagnosis and treatment are challenging. Angiography is beyond the capability of available teams during wartime. Thus, computed tomographic angiography (CTA) may become a major triage tool. This study reports on the presentation, diagnosis, management and outcome of combat vascular injuries with emphasis on the utility of CTA. Presenting signs and symptoms, means of diagnosis, treatments and results of all combat sustained vascular cases were collected and compiled with follow-up. Of 511 patients, 39 patients (7.6%) with vascular injuries were admitted. Injuries were penetrating and accompanied by soft tissue and bone insult. Diagnosis was made by CTA in 62% and by surgical exploration in 38%. Extremity arteries were injured in 72% of cases. Treatment included surgical and endovascular techniques. COMPLICATIONS: one late amputation, 5% thrombosis, 24% wound infections with no mortalities or early amputations. Although similarities exist between this experience and recent wartime reports, differences are apparent including the effectiveness of CTA. High index of suspicion and liberal use of CTA allows for an early and accurate diagnosis of a vascular injury resulting in high rates of limb salvage and low mortality. CTA should be the first line modality for diagnosis of vascular injuries, reserving angiography for endovascular treatment.

Feasibility of automatic assessment of four-chamber cardiac function with MDCT: Initial clinical application and validation.

BACKGROUND: The ability to perform a simultaneous analysis of ventricular and atrial volumes may provide clinically useful information for diagnosis and prognosis. We aimed to evaluate the feasibility and clinical value of a novel algorithm that performs fully automatic evaluation of the four cardiac chambers and myocardium from gated CT datasets. METHODS: 50 patients were studied-Group 1: 30 consecutive unselected patients, Group 2A: 10 patients after myocardial infarction and Group 2B: 10 normal controls. Fully automatic, segmentation of the heart was performed with a model-based segmentation algorithm requiring no user input other than loading the datasets. Qualitative and quantitative evaluation of segmentation quality was performed. Left ventricular (LV) and right ventricular (RV) stroke volumes (SV) were compared. RESULTS: Overall, segmentation succeeded in all patients although 11/500 (2.2%) cardiac chambers achieved poor segmentation grading. Correlation coefficients between automatic and manually derived volumes were excellent (r>0.98) for all chambers. Bland-Altman analysis showed minimal bias (-1.0ml, 0.4ml, -1.8ml) for the LV and RV, and right atria, respectively, with mild overestimation of LV myocardial volume (5.2ml). Significant, yet consistent, overestimation of left atrial volume (23.6ml) due to inclusion of proximal pulmonary veins was observed. LV and RV ejection fraction (r=0.91 and 0.98) and SV (r=0.98 and 0.99) also correlated closely with minimal bias (<2%). Most significantly, LV SV (91.0+/-21.6ml) correlated highly with RV SV (81.7+/-18.2ml, r=0.86). Outliers could usually be explained by valvular regurgitation. CONCLUSIONS: Fully automatic segmentation of all cardiac chambers can be achieved with high accuracy over multiple cardiac phases, enabling reliable comprehensive evaluation of four-chamber cardiac function.

Hybrid cardiac SPECT/64-slice CTA-derived LV function parameters: correlation and reproducibility assessment.

UNLABELLED: The purpose of this study is to define the relationship between SPECT and CTA measured parameters of left ventricular (LV) function and volumes obtained in a single session using SPECT/64-slice CT hybrid imaging device, and in addition, to assess the reproducibility of LV parameters measured using 64-slice CTA. MATERIALS AND METHODS: Seventy-six patients with suspected or known coronary artery disease underwent cardiac CTA and GSPECT in one session using a hybrid SPECT/CT device. LV end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were measured on each component of the hybrid device. For the CTA component, these parameters were re-measured by the same investigator and by a second investigator with an interval of 3-54 weeks. Corresponding GSPECT and CTA measured parameters were compared. For CTA, intra-observer and inter-observer variability of LV function and volume measurements were calculated. RESULTS: A very good correlation was found between the GSPECT and CTA measured LVEF (r=0.81), ESV (r=0.90) and EDV (r=0.82). There was a small positive difference by CTA measured LVEF (3.9+/-14.2%), and more prominent positive differences by CTA measured ESV and EDV (9.8+/-14.8 and 44.9+/-23.1cm(3), respectively). There was excellent reproducibility in the measurements of all parameters with very low intra- and inter-observer variability (r=0.93 for EF and 0.98 for EDV and ESV). CONCLUSIONS: Although a good correlation was found between the EF measurements obtained from CTA and SPECT, interchangeable use of EF measurements between the two modalities should be done cautiously and interchangeable use of LV EDV and ESV should be avoided.

Coping with war mass casualties in a hospital under fire: the radiology experience.

OBJECTIVE: We report the role of the imaging department at a level 1 trauma center during the Second Lebanon War (summer 2006). Our institution received 849 military and civilian casualties, an average of 25 war-injured patients per day, 338 with acute traumatic stress disorders and 511 physically injured, coming in waves after a rocket attack or a battle confrontation. About 12 potentially critical physically injured patients per day were referred to the imaging department for sometimes complex imaging procedures. The unpredictable waves of casualties and nature of the injuries forced us to reorganize our routine workflow to provide adequate care to casualties and to nonemergent patients. Our nurses' station was transformed into a small emergency department. The radiology staff was distributed into 12 diagnostic stations, providing 24-hour service. Communication was improved by means of walkie-talkies. Three ultrasound units were placed at the emergency department for immediate focused assessment with sonography for trauma performance enabling initial triage of patients. The site and extent of injuries were accurately diagnosed on CT and CT angiography. Digital angiography allowed definitive vascular diagnosis and interventional procedures. CONCLUSION: Adequate communication, strict workflow, and correct use of imaging protocols ensured optimal triage, diagnosis, and therapy of casualties while maintaining care for nonwar patients.

Pseudopancreatitis in trauma patients.

OBJECTIVE: The purpose of our study was to review the significance of intra- and peripancreatic fluid in trauma patients who have no other signs of pancreatic injury. CONCLUSION: We propose that intra- and peripancreatic fluid may be the consequence of hypovolemic shock treated with hyperhydration when there is significant delay between injury and imaging.

Novel method for real-time hybrid cardiac CT and coronary angiography image registration: visualising beyond luminology, proof-of-concept.

AIMS: During coronary angiography and percutaneous coronary interventions (PCI) only the lumen of the coronary vessel is imaged. The complete pathology of the vessel wall--namely the extent of calcification, structure of non-calcified plaque and lesion length--cannot be accurately determined. These can be imaged using coronary CT angiography (CTCA). We aimed to investigate the accuracy, feasibility, safety and value of a novel hybrid method encapsulating real-time registration of CTCA to coronary angiography images. The method is designed to seamlessly integrate into the routine catheterisation procedures and provide information to assist in decision making during the interventional procedure. METHODS AND RESULTS: Phantoms simulating the coronary tree were used to test the accuracy and potential of co-registration of information. Precision of the imaging system was tested using radio-opaque markers and distance between bifurcations. We included patients who underwent CTCA and also underwent cardiac catheterisation. Analysis and feasibility was performed offline in the first twenty patients and online in the following 19 patients. The online CTCA and angiography co-registration was performed by the AngioCt software program. The registration result was displayed on a separate screen in the catheterisation laboratory as a three-dimensional coronary tree and a curved multi-planar reformat (MPR) view. Preclinical validation showed that the co-registration of the coronary tree is feasible, and measurements of length and diameter are precise for all standard working angulations during coronary angiography. Real-time registration was successful in all cases and aided in selection of the view that will provide the least foreshortening and no vessel overlapping, the length of balloons and stent to use and assisted in crossing chronic total occlusions (CTO). CONCLUSIONS: This is the first report of a novel method for online real-time hybrid CTCA and angiography registration. In this pilot study we found that this method is feasible, accurate, and easy to use. It can be used for selecting the best working angulations for minimising foreshortening and vessel overlapping, determining stent size and location, and providing a reference vessel path and structure in cases of CTO.

Clinical evaluation of a fully automated model-based algorithm to calculate left ventricular volumes and ejection fraction using multidetector computed tomography.

OBJECTIVES: To evaluate feasibility and accuracy of a fully automatic algorithm (FAA) for calculating left ventricular volumes and ejection fraction (LVEF) from multidetector computed tomography (MDCT) studies versus a previously validated method based on Simpson's method serving as our reference standard (RS), and left ventriculography (LVG), in patients with acute chest pain (ACP). METHODS: 23 patients admitted with ACP underwent ECG-gated MDCT, as well as LVG during their hospitalization. MDCT based end-diastolic, end-systolic and stroke volumes (EDV, ESV, SV) and LVEF were calculated using the RS and the FAA. RESULTS: One patient was excluded after FAA failure to detect contours. In the remaining 22 patients, mean+/-SD LVEF measurements were RS 61+/-11%, FAA 59+/-11% (r = 0.91 versus RS), LVG 57+/-16% (r = 0.6 versus RS). In comparison to RS, FAA overestimated EDV by 10.1+/-8.5 ml, ESV by 7.3+/-6.4 ml and SV by 3.6+/-8.6 ml, and underestimated LVEF measurements by 2.7+/-4.6%, related to contour smoothing. LVEF by FAA was within 8% of RS for all patients except one. In contrast, LVG differed significantly from RS. CONCLUSIONS: The evaluated FAA obtained accurate, clinically relevant results for left ventricular volumes and LVEF relative to the RS.

Multidetector CT angiography in the evaluation of acute mesenteric ischemia.

The aim of this study was to determine the accuracy of multidetector row CT angiography in the diagnosis of acute mesenteric ischemia. Ninety-three consecutive studies on 91 patients with clinically suspected acute mesenteric ischemia underwent abdominal CT angiography as the first, and usually the sole, diagnostic procedure. CT was performed with a multidetector 16-row CT system from the level of the diaphragm to the pelvis in two phases: early arterial and late portal phase. CT examinations were reviewed by the duty radiologist. Final diagnosis was established by a senior radiologist. CTA was diagnostic in 92 studies. Mesenteric ischemia was diagnosed in 18 patients, 14 of them were of the thromboembolic type and four from the nonocclusive type. Positive CTA findings were confirmed by surgery in 13 patients and by clinical follow-up in three cases. Other reasons for abdominal pain were diagnosed by CT in 38 patients out of the remaining 74. There were two false positive and two false negative CT results, resulting in an overall accuracy of 95.6%. Multidetector CT angiography is a fast and accurate investigation for the diagnosis of acute mesenteric ischemia and in most cases can be used as the sole diagnostic procedure.

Cardiology consultation as a gatekeeper prior to cardiac multi-detector computed tomography scan.

BACKGROUND: Multi-detector computed tomography has advanced enormously and now enables non-invasive evaluation of coronary arteries as well as cardiac anatomy, function and perfusion. However, the role of cardiac MDCT is not yet determined in the medical community and, consequently, many clinically unnecessary scans are performed solely on a self-referral basis. OBJECTIVES: To prospectively evaluate the role of a cardiologist consultation and recommendation prior to the scan, and the influence on the diagnostic yield of cardiac MDCT. METHODS: In our center a CT service was initiated, but with the prerequisite approval of a cardiologist before performance of the CT. Each individual who wanted and was willing to pay for a cardiac CT was interviewed by an experienced cardiologist who determined whether cardiac MDCT was the most appropriate next test in the cardiovascular evaluation. Subjects were classified into three groups: a) those with a normal or no prior stress test, no typical symptoms and no significant risk factors of coronary artery disease were recommended to perform a stress test or to remain under close clinical follow-up without MDCT; b) those with an equivocal stress test, atypical symptoms and/or significant risk factors were allowed to have cardiac MDCT; and c) those with positive stress test or clinically highly suspected CAD were advised to go directly to invasive coronary angiography. CT findings were categorized as normal CAD (normal calcium score and no narrowings), < 50% and > 50% CAD. RESULTS: A total of 254 people were interviewed, and in only 39 cases did the cardiologist approve the CT. However, 61 of the 215, despite our recommendation not to undergo CT, decided to have the scan. Assessment of the 100 cases that underwent MDCT showed a statistically significant better discrimination of significant CAD, according to the cardiologist's recommendation: MDCT not recommended in 3/54 (6%) vs. MDCT recommended in 12/39 (31%) vs. recommended invasive coronary angiography in 4/7 (57%)(P<0.001). CONCLUSIONS: Detection of coronary calcification, as well as MDCT angiography can provide clinically useful information if applied to suitable patient groups. It is foreseeable that MDCT angiography will become part of the routine workup in some subsets of patients with suspected CAD. Selection of patients undergoing MDCT scans by a cardiologist improves the ability of the test to stratify patients, preventing unnecessary scans in both high and low risk patients.

Diagnosing acute appendicitis in adults: accuracy of color Doppler sonography and MDCT compared with surgery and clinical follow-up.

OBJECTIVE: The objective of our study was to evaluate the accuracy of color Doppler sonography and contrast-enhanced MDCT in the diagnosis of acute appendicitis in adults and their utility as a triage tool in lower abdominal pain. MATERIALS AND METHODS: We reviewed the medical records of 420 consecutive adult patients, 271 women and 149 men, 18 years old or older, referred from the emergency department to sonography examination for clinically suspected acute appendicitis between January 2003 and June 2006. Patients underwent sonography of the right upper abdomen and pelvis followed by graded compression and color Doppler sonography of the right lower quadrant. CT was performed in 132 patients due to inconclusive sonography findings or a discrepancy between the clinical diagnosis and the sonography diagnosis. Sonography and CT reports were compared with surgery or clinical follow-up as the reference standard. Statistical analyses were performed by Pearson's chi-square test and cross-tabulation software. RESULTS: Sonography and CT correctly diagnosed acute appendicitis in 66 of 75 patients and in 38 of 39 patients, respectively, and correctly denied acute appendicitis in 312 of 326 and in 92 of 92 patients. Sonography was inconclusive in 17 of 418 cases and CT, in one of 132 cases. Sonography and CT allowed alternative diagnoses in 82 and 42 patients, respectively. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for sonography were 74.2%, 97%, 88%, 93%, and 92%, respectively, and for CT, 100%, 98.9%, 97.4%, 100%, and 99%. CONCLUSION: Sonography should be the first imaging technique in adult patients for the diagnosis of acute appendicitis and triage of acute abdominal pain. CT should be used as a complementary study for selected cases.