Negative Predictive Value Of CT Research Articles

Per-patient Negative Predictive Value of the CT and MRI Liver Imaging Reporting and Data System Version 2018 Treatment Response Algorithm for Hepatocellular Carcinoma.

Background The Liver Imaging Reporting and Data System version 2018 (LI-RADS) treatment response algorithm (TRA) is a high-specificity, lower-sensitivity grading system to diagnose hepatocellular carcinoma (HCC) and recurrence after local-regional therapy. However, the emphasis on specificity can result in disease understaging, potentially leading to poorer posttransplant outcomes. Purpose To determine the negative predictive value (NPV) of pretransplant CT and MRI assessment for viable HCC on a per-patient basis using the LI-RADS TRA, considering explant pathology as the reference standard. Materials and Methods Patient records from 218 consecutive adult patients from a single institution with HCC who underwent liver transplant from January 2011 to November 2017 were retrospectively reviewed. Two readers blinded to the original report reviewed immediate (within 90 days) pretransplant imaging and characterized observations according to the LI-RADS TRA. Based on this, patients with LR-4, LR-5, or LR-TR (treatment response) viable tumors were designated as viable tumor; patients with solely LR-3 or LR-TR equivocal tumors were designated as equivocal; and patients with only LR-TR nonviable lesions were designated as no viable disease. Patients were designated as within or outside the Milan criteria. These per-patient designations were compared with the presence of viable disease at explant pathology. Fisher exact test was used to compare the differences between CT and MRI. Weighted κ values were used to calculate interreader reliability. Results Final study sample consisted of 206 patients (median age, 61 years [IQR, 57-65 years]; 157 male patients and 49 female patients). Per-patient LI-RADS TRA assessment of pretransplant imaging had an NPV of 32% (95% CI: 27, 38) and 26% (95% CI: 20, 33) (readers 1 and 2, respectively) for predicting viable disease. Seventy-five percent (reader 1) and 77% (reader 2) of patients deemed equivocal had residual tumors at explant pathology. Weighted interreader reliability was substantial (κ = 0.62). Conclusion Patient-based stratification of viable, equivocal, and nonviable disease at pretransplant CT or MRI, based on LI-RADS TRA, demonstrated low negative predictive value in excluding HCC at explant pathology. © RSNA, 2023 See also the editorial by Tamir and Tau in this issue.

The Role of CT in Assessment of Extraregional Lymph Node Involvement in Pancreatic and Periampullary Cancer: A Diagnostic Accuracy Study.

To investigate the diagnostic accuracy of CT in assessing extraregional lymph node metastases in pancreatic head and periampullary cancer. This prospective observational cohort study was performed at two tertiary hepatopancreatobiliary (HPB) referral centers between March 2013 and December 2014. Patients undergoing pancreatoduodenectomy or bypass surgery with or without palliative radiofrequency ablation were included. Extraregional lymph node involvement was defined as positive lymph nodes in the aortocaval window. Two expert HPB radiologists assessed aortocaval lymph nodes at preoperative CT according to a standardized protocol. All tissue from the aortocaval window was collected intraoperatively. Positive histopathologic finding was the reference standard. Analysis of predictive values and diagnostic accuracy was performed. A total of 198 consecutive patients (mean age, 66 years; range, 39-86 years; 105 men) with pancreatic head or periampullary carcinoma were included. In 70% of patients, a pancreatoduodenectomy was performed, 4% underwent total pancreatectomy, 4% underwent radiofrequency ablation, and 22% underwent bypass surgery. Forty-four patients (22%) had histologically positive aortocaval lymph nodes. Negative predictive value of CT in assessing aortocaval lymph nodes was 80% for both observers, and positive predictive value was 31%-33%. Overall diagnostic accuracy was 69%-70%. CT has a low diagnostic accuracy in assessing extraregional lymph node metastases in patients suspected of having pancreatic or periampullary cancer.Keywords: CT, Abdomen/GI, Pancreas, Oncology© RSNA, 2021.

Reliability of coronary computed tomography angiography in acute coronary syndrome in an emergency setting

BackgroundCardiovascular computed tomography (cardiovascular CT) is currently used as a fast non-invasive method for the visualization of coronary plaques and walls and the assessment of lumen stenosis severity. Previous studies demonstrated the high negative predictive value of CT for the exclusion of coronary lumen stenoses. In this study we hypothesize that coronary CT angiography (CTA) represents a reliable method as diagnostic procedure in acute coronary syndrome (ACS) even in emergency settings. Methods36 patients (51 lesions) with ACS who underwent cardiovascular CT, intravascular ultrasound (IVUS) and invasive coronary angiography (ICA) within 48 h were included. The percentage of coronary stenoses were measured and compared by three methods. Influence of available predictors that can potentially affect the measurement results was assessed. ResultsCardiac CTA provided comparable results to IVUS (mean difference -0.45%, PPV: 98%, NPV: 75%). ICA tends to estimate lower stenoses degrees than cardiac CTA and IVUS (mean difference 13.19% and 13.64%, respectively). The final diagnosis and positive remodeling did not lead to any significant influence on measurements. ConclusionsThe cardiovascular CT results show that even in emergency settings it is possible to identify morphological changes as sequels of coronary artery sclerosis with comparable results to the reference method IVUS. Deviations of IVUS and cardiovascular CT from ICA are comparable and can to a large extent be explained by differences in the measurement technique.

Negative predictive value of CT for occult fractures of the hip and pelvis with imaging follow-up

To determine the negative predictive value of multidetector CT for radiographically occult fracture of the hip or pelvis in an elderly population presenting to the emergency department. Two hundred thirty-seven elderly patients with suspected fracture were identified over a 5-year period with negative radiographs acquired in the emergency department followed by an index CT of the hip/pelvis within 24h. There were 81 cases with a negative index CT, as determined by 2 musculoskeletal radiologists, and with some form of imaging follow-up (MRI, CT, or x-ray) performed within 18months of the index CT. Follow-up imaging was reviewed by 2 musculoskeletal radiologists for the presence of fracture to determine the performance of the index CT. The electronic medical record was used to exclude the possibility of intervening trauma between the time of the index CT and follow-up imaging. There were 39 cases with follow-up imaging performed within 6weeks of the negative index CT, and 42 with follow-up imaging within 6weeks to 18months of the negative index CT. Eight of 81 patients demonstrated a fracture on follow-up imaging, with 3 of 8 involving the femoral neck or intertrochanteric femur. The negative predictive value of the index CT for the detection of a radiographically occult hip or pelvic fracture was 90.1%. If considering only surgically relevant fractures (femoral neck and intertrochanteric fractures), the negative predictive value improved to 96.3%. Computed tomography for occult hip fractures has a high negative predictive value but there are cases not detected with surgical implications.

Diagnostic Utility of CT and Fluoroscopic Esophagography for Suspected Esophageal Perforation in the Emergency Department.

OBJECTIVE. We evaluated the diagnostic utility of CT in emergency department (ED) patients with suspected esophageal perforation and assessed whether subsequent fluoroscopic esophagography is necessary. MATERIALS AND METHODS. This retrospective study included consecutive adult patients presenting to an urban academic tertiary care ED from January 1, 2000, to August 31, 2017, who underwent CT and fluoroscopic esophagography within 1 calendar day (< 27 hours) of each other for suspected esophageal perforation. The use of oral or IV contrast material and the CT findings (i.e., pneumomediastinum, pleural effusion, pneumothorax, unexplained mediastinal fluid or stranding, esophageal wall air or frank esophageal wall disruption, or extraluminal oral contrast material) were documented. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Surgical or procedural intervention results or clinical follow-up results were the reference standard. RESULTS. One hundred three patients met the inclusion criteria. Sensitivity, specificity, PPV, and NPV for diagnosing esophageal perforation were 100.0%, 79.8%, 32.1%, and 100.0%, respectively, with CT and 77.8%, 98.9%, 87.5%, and 97.9% with fluoroscopic esophagography. Combining CT and fluoroscopic esophagography did not improve sensitivity, specificity, PPV, or NPV relative to using CT alone. The true-positive esophageal perforation rate was 8.7% for CT and 6.8% for fluoroscopic esophagography. When CT showed only pneumomediastinum (n = 51) or no pneumomediastinum (n = 14), the NPV of CT was 100.0%. CT with oral contrast material had a PPV of 38.5%, whereas CT without oral contrast material had a PPV of 26.7%. CONCLUSION. CT has a high NPV similar to that of fluoroscopic esophagography and has greater sensitivity than fluoroscopic esophagography for diagnosing suspected esophageal perforation. Fluoroscopic esophagrams do not provide additional information that changes clinical management beyond the information that CT provides. In ED patients with suspected esophageal perforation, CT with oral contrast material should be considered the initial imaging examination and can obviate fluoroscopic esophagography.

Diabetes mellitus, obesity and chronic pancreatitis? Independent risk factors for pancreatic adenocarcinoma (PAC) in Romanian Black Sea coast area

Patients & methods: Prospective diagnostic accuracy study in a tertiary HPB center according to the STARD guidelines. We included patients undergoing pancreatoduodenectomy or radiofrequency ablation (RFA) combined with bypass surgery. Extra-regional lymph nodes were defined as lymph nodes in the aortocaval window. An expert HPB-radiologist prospectively assessed aortocaval lymph nodes on preoperative CT according to a standardized protocol. All tissue from the aortocaval window was harvested intra-operatively. The reference test was histopathology. Results: Between March 2013 and December 2014, 77 consecutive patients were included. In 69 patients (90%) a pancreatoduodenectomy was performed and 8 patients underwent RFA (n1⁄47) or only bypass (n1⁄41). A median of 3 aortocaval lymph nodes(IQR 1-4) were harvested per patient. Nine patients (12%) had aortocaval LNM. Negative predictive value of CT in assessing aortocaval LNM was 88%(95%CI 77-94%) and positive predictive value was 10%(CI 1-46%). Overall diagnostic accuracy was 22%. Conclusion: CT has a low diagnostic accuracy in assessing extraregional LNM in pancreatic or peri-ampullary cancer, mainly due to the high number of false positive results. Signs of aortocaval LNM on CT should therefore not be a contra-indication for surgical exploration or other treatments that are part of a strategy with curative intent.

Preliminary discussion on the value of 18F-FDG PET/CT in the diagnosis and early staging of non-mycosis fungoides/Sézary's syndrome cutaneous malignant lymphomas

ObjectiveTo discuss the value of 18F-fluorodeoxyglucose-positron emission tomography (18F-PET/CT) scans in the diagnosis and early staging of non-mycosis fungoides/Sézary's syndrome cutaneous malignant lymphomas (non-MF/SS CML). Materials and methodsA total of 18 cases with non-MF/SS CML, confirmed by pathology or on clinical grounds, were analyzed in this study. The sensitivity of CT and PET/CT scans in the diagnosis of primary skin lesions, as well as the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT and PET/CT scans in the diagnosis of lymph nodes (LNs) and other organs (except skin and LNs) were calculated. ResultsThe diagnostic sensitivity of CT and PET/CT scans in the diagnosis of primary skin lesions was 82.4% (14/17) and 100% (17/17), respectively. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT and PET/CT scans in the diagnosis of LN lesions were 55.6% (5/9), 88.9% (8/9), 72.2% (13/18), 83.3% (5/6), 66.7% (8/12), and 88.9% (8/9), 100% (9/9), 94.4% (17/18), 100% (8/8), 90.0% (9/10), respectively. The diagnostic value of the CT and PET/CT scans in the diagnosis of involvement of other organs, were 40.4% (2/5), 100% (13/13), 83.3 (15/18), 100% (2/2), 81.3% (13/16) and 80.6% (4/5), 100% (13/13), 94.4% (17/18), 100% (3/3), 92.9% (13/14), respectively. Conclusions18F-FDG PET/CT has high value in the diagnosis and early staging of non-MF/SS CMLs.

Esophagography After Pneumomediastinum Without CT Findings of Esophageal Perforation: Is It Necessary?

The purpose of our study was to determine the necessity of fluoroscopic esophagography in patients with pneumomediastinum on CT but without CT findings of esophageal perforation. From January 1, 2006, through December 31, 2010, there were 4305 fluoroscopic esophagography examinations including 533 with CT identified from a search of our PACS. Patients with pneumomediastinum on CT who were subsequently referred for emergent fluoroscopic esophagography to exclude esophageal perforation were enrolled. Fluoroscopic esophagography examinations performed within 3 days of CT were included. Patients with a history of esophageal disease were excluded. As a result, 103 patients were enrolled in the study; patients were divided into groups on the basis of whether there was additional clinical history of esophageal damage (trauma group) or not (nontrauma group). Images were reviewed by two board-certified radiologists blinded to the clinical data and radiologic reports for the presence or absence of esophageal perforation. A positive result on CT was defined as esophageal injury or periesophageal infiltration that coexisted with periesophageal air. A positive fluoroscopic esophagography result was defined as oral contrast medium leakage from the esophagus. Esophageal perforation was diagnosed in 15 of the 103 patients. The CT findings were significantly correlated with esophageal perforation (p < 0.001 in the trauma group, and p = 0.001 in the nontrauma group). The respective sensitivity and negative predictive value (NPV) of CT versus fluoroscopic esophagography in the trauma group were 100% versus 66.7% and 100% versus 87.9%; in the nontrauma group, the sensitivity and NPV were 100% for CT and fluoroscopic esophagography. Thus, the sensitivity and NPV of CT were either superior or equal to those of fluoroscopic esophagography. The results of our study suggest that performing fluoroscopic esophagography in patients with pneumomediastinum is unnecessary when CT is negative for esophageal perforation.

Differentiation of malignant from benign heart and pericardial lesions using positron emission tomography and computed tomography

ObjectiveTo assess the feasibility of 18F-FDG PET-CT for the differentiation of malignancy from benign lesions of the heart and the pericardium. MethodsA total of 23 cases (malignancy:benign = 13:10) with cardiac and pericardial lesions, confirmed by pathology or on clinical grounds, were analyzed in this study. All lesions were evaluated semi-quantitatively using maximum standard uptake values (SUVmax) and SUVmax lesion/blood, and the density of the heart and pericardium lesions and the relation with surrounding tissues were evaluated. The differences of SUVmax and SUVmax lesion/blood between benign and malignant lesions were analyzed by the Mann-Whitney test. Subsequently, the diagnostic sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated for CT and PET-CT, respectively. ResultsThe maximum SUV showed significant difference between malignancy (avg ± SD 6.5) and benign (avg ± SD 1.5) (Z = −3.601, P < .01), the SUVmax lesion/blood of malignancy and benign were avg ± SD 3.4 and avg ± SD 0.9, respectively, also with a significant difference (Z = −3.600, P < .01). In this pilot study, the optimal cutoff value to separate benign vs malignant lesions of SUVmax was 3.5-4.0 and the cutoff for SUVmax lesion/blood was 1.3-2.0. The sensitivity, specificity, accuracy, PPV, and NPV of CT and PET-CT were 76.9%(10/13), 100.0%(10/10), 87.0%(20/23), 100.0%(10/10), 76.9%(10/13) and 100.0%(13/13), 90.0%(9/10), 95.7%(22/23), 92.9%(13/14), 100.0%(9/9), respectively. Conclusion18F-FDG PET-CT appears promising for correctly differentiating benign vs malignant cardiac and pericardial lesions.

Differentiation of benign from malignant lesions of heart and pericardium: the feasibility of Fluorine-18 fluorodeoxyglucose positron emission tomography CT

Objective To assess the feasibility of integrated 18F-FDG PET-CT for the differentiation of malignancy from benign lesions of heart and pericardium. Methods A total of 23 cases (malignancy∶benign= 13∶10) with cardiac and pericardial lesions confirmed by pathology or clinic were analyzed in the present study. All lesions were evaluated semi-quantitatively using maximum standard uptake values (SUVmax) and SUVmax lesion/blood, and the density of the heart and pericardium lesions and the relationship with surrounding tissues were evaluated. The differences of SUVmax and SUVmax lesion/blood between benign and malignant lesions were analyzed using Mann-Whitney test. Subsequently, the diagnostic sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were calculated for CT and PET-CT respectively. Results The maximum SUV showed significant difference between malignancy(6. 5 ) and benign ( 1.5 ) ( Z = - 3. 601, P ＜ 0. 01 ), the SUVmax Lesion/Blood of malignancy and benign were 3.4 and 0. 9 respectively, also with significant difference(Z = -3. 600, P ＜0. 01 ). The optimal cut-off value of SUVmax is 3.5-4. 0 and SUVmax Lesion/Blood is 1.3-2. 0. The sensitivity, specificity, accuracy, PPV and NPV of CT and PET-CT were 76. 9％ ( 10/13 ), 100. 0％ ( 10/10) ,87.0％ (20/23), 100. 0％ ( 10/10 ), 76. 9％ ( 10/13 ) and 100. 0％ ( 13/13 ), 90. 0％ (9/10), 95.7％(22/23),92.9％ (13/14),100.0％ (9/9) respectively. Conclusion 18F-FDG PET-CT can correctly differentiate benignity and malignancy of cardiac and pericardial lesions. Key words: Pericardium; Heart neoplasms; Tomography, X-ray computed; Positron-emission tomography; Diagnosis, differential

Coronary artery disease in patients with cardiac tumors: preoperative assessment by computed tomography coronary angiography☆

We studied the diagnostic accuracy of computed tomography coronary angiography (CTCA) for the diagnosis of significant coronary artery disease (CAD) compared to conventional coronary angiography (CCA) in patients with primary cardiac tumors. Thirty-eight consecutive patients with primary cardiac tumors (27 females, 11 males; mean age 56+/-6 years, range 32-86 years) underwent dual-source CTCA and CCA. Significant stenosis was defined as diameter reduction >50%. CCA served as the standard of reference. The prevalence of significant CAD in the study population was 8% (3/38 patients). Five of 544 segments (0.9%) in 1/38 patients (2.6%) was considered of non-diagnostic image quality on CTCA because of motion artifacts. In a segment-based analysis taking not-evaluative segments as false-positive, sensitivity, specificity, positive and negative predictive value of CT was 100%, 99%, 70%, and 100%, respectively. Preoperative CCA could have been avoided in 95% (36/38) of the patients and CCA would have confirmed the CTCA diagnosis in 5% (2/38) of the patients. Our results indicate that CTCA provides a high diagnostic performance for diagnosing significant CAD in patients with primary cardiac tumors. CTCA may thus be used as a filter test prior to surgery.

Biliary complications after liver transplantation: diagnosis with multi-slice CT

Objective To evaluate multisliee CT in the diagnosis of biliary complications after liver transplantation. Methods Eighty-three consecutive patients who had undergone orthotopic liver transplantation (OLT) presented with clinical or biochemical signs of biliary complications and underwent contrast-enhancement CT examination. Three experienced radiologists, who were blinded to patient's clinical data, assessed CT images for the detection of biliary complications in consensus. Diagnostic confirmation of biliary complications was obtained with direct cholangiography in 69 patients, histologie study in 11 patients and hepatieojejunostomy in 3 patients. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT for the detection of biliary complications were calculated. In addition, CT features of anastomotie biliary stricture (ABS) were compared with those of non-anastomotie biliary stricture (NABS) using x2 test. Results A total of 62 biliary complications (74. 7% ) was eventually confirmed in the 83 patients, including ABS in 32 patients, NABS in 21 patients, biliary duct stones in 16 patients (of which 12 patients with biliary stricture), anastomotie bile leakage in 5 patients, biloma in 4 patients with biliary stricture, and biliogenic abscess in 2 patients with biliary stricture. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT for the detection of biliary stricture were 90. 6%、86. 7%、89. 2%、92. 3% and 83.9% , respectively. Other biliary complications, including biliary duct stones ( 16 cases) , anastomotic bile leak (5 cases) , biloma (4 cases), and biliogenic abscess (2 cases), were correctly diagnosed by CT; there was no false-positive or false-negative result. The incidence of irregular dilatation of bile duct was 71.4% ( 15/21 ), which was significantly higher in NABS cases than in ABS of 25.0% (8/32,P <0. 01 ) ; whereas the incidence of extrahepatie biliary dilatation was 33.3% (7/21) and regular dilatation was 14. 3% (3/21), which was significantly lower in NABS cases than in ABS of 84. 4% ( 27/32 ) and 68. 8% ( 22/32 ), respectively ( P < 0. 01 ). Of 21 patients with NABS, 66. 7% (14/21)complicated with hepatic artery stenosis or thrombosis, which was markedly more than that of NABS cases (15. 6%, 5/32,P <0. 01 ). Conclusions Multislice CT is a useful imaging procedure in the detection of biliary complications after liver transplantation, and biliary stricture can be primitively classified into ABS and NABS by CT. Hepatic artery ischemia is an important factor that causes NABS. Key words: Liver transplantation; Postoperative complications ; Biliary tract; Tomography, X-ray computed

CT-Koronarangiografie: Untersuchungstechnik, klinische Ergebnisse und Ausblick in zukünftige Entwicklungen

Multislice computed tomography (MSCT) after intravenous contrast agent administration enables visualization of the coronary arteries with high spatial resolution (voxel sizes down to 0.5 x 0.35 x 0.35 mm (3)) and a short scan time. Magnetic resonance imaging (MRI) is also intensively studied with respect to the noninvasive detection of coronary artery stenosis and thus the detection of coronary artery disease (CAD) without radiation exposure but is not equal to MSCT at present. This article provides an overview of the historical development of CT coronary angiography from 4-slice CT to 16-slice CT and 64-slice CT. A crucial aspect of this development is the improvement in image quality resulting from shorter breath-hold periods and the reduced gantry rotation time. Other techniques that appear to considerably improve image quality and accuracy and make CT independent of patient heart rates are multi-segment reconstruction and dual-source CT. Sublingual nitroglycerin as well as oral or intravenous betablocker administration should be considered in relation to the diagnostic question to be answered and the patient's heart rate. In the studies available CT coronary angiography with at least 12 simultaneous detector rows has a sensitivity of 96.9 % and a specificity of 75.3 % at the patient level. Especially the negative predictive value of CT (94.6 %) emphasizes the idea that this technique may reliably exclude CAD in patients with intermediate pretest likelihood. In the near future, 256-slice CT will allow examination of the entire heart during one heartbeat or even 4D CT scanning with simultaneous assessment of myocardial perfusion. Automatic or semiautomatic software tools will assume a central place in detecting and quantifying coronary artery stenoses and plaques as well as in the analysis of cardiac function in the clinical setting over the next years. Prior to its routine clinical use, the cost-effectiveness of CT coronary angiography must be determined and the clinical role of MSCT must be investigated in multi-center studies including different patient populations.

Utilization of thick (&gt;3 mm) maximum intensity projection images in coronary CTA interpretation

elevated the role of the Emergency Radiologist in the screening of trauma patients or patients with suspected pulmonary embolism (PE), 64-slice multidetector computed tomography (MDCT) and advanced image postprocessing workstations are poised to change the screening algorithms in patients who present to emergency medicine facilities with chest pain. As emergency radiologists acquire and gain experience with advanced CT technology, they should assume a leadership role in the imaging evaluation for a considerable fraction of this patient population, over 5 million patients annually. Less than 20% of the total patient population has coronary artery disease, emphasizing the potential of the high negative predictive value of CT. Moreover, the image acquisition and postprocessing software, already capable of chest pain imaging, continues to evolve. It may be the case that chest pain imaging will mirror the history of PE computed tomography angiography (CTA). That is, early single slice helical CT scanners with relatively thick slices, slow gantry rotation times, and evolving postprocessing tools were cumbersome, but they were both noninvasive and diagnostic. As CT evolved and Emergency Radiologists gained familiarity with the imaging and interpretation, PE CTA protocols became streamlined and routine, and are now a mainstay of our field. With the opportunity of expanding Emergency Radiology with chest pain patients comes the challenge of staffing, education, and both accurate and timely reporting. This letter offers some comments on accurate and timely reporting. In order to spatially resolve a proximal and midcoronary artery that has a 3-mm diameter, coronary CTA requires thin section (<1 mm) imaging with reconstructed images that are roughly 0.5 mm. Moreover, coronary CTA requires electrocardiogram (ECG) gating and thin section data sets are created throughout the cardiac cycle. The increased utilization of ECG-gated and thin section imaging will usher in a paradigm shift in the use of image postprocessing software in Emergency Radiology. Specifically, postprocessing software packages will advance from the role of a supplementary, problem-solving tool to become the primary means of image interpretation. In addition to improved handling of very large data sets, postprocessing software packages enable the user to create multiplanar reformatted (MPR) and maximum intensity projection (MIP) images [1] in multiple planes. Vendors have also designed software supporting specific workflows in coronary CT interpretation, with the intent of improving efficiency of either the radiologist or the cardiologist.

Assessment of Anomalous Pancreaticobiliary Ductal Junction with High-Resolution Multiplanar Reformatted Images in MDCT

The objective of our study was to assess the capabilities of MDCT for the diagnosis of an anomalous pancreaticobiliary ductal junction using high-resolution multiplanar reformatted (multiplanar reconstruction) images. This study included nine patients with and 54 without an anomalous pancreaticobiliary ductal junction confirmed on direct cholangiopancreatography. Multiplanar reconstruction images with 0.5-mm continuous slices were generated from isotropic or nearly isotropic pancreatic phase images. By mainly interpreting the multiplanar reconstruction images using the Scrolling mode, two blinded reviewers independently determined whether the confluence of the pancreatic and biliary ducts joined in the pancreatic parenchyma (in other words, outside the duodenal wall). The results were correlated with the findings of direct cholangiopancreatography. The diagnostic capabilities of CT for revealing associated pancreatobiliary diseases were assessed in patients with this anomaly. Interobserver agreement in the classification of the duct confluence was high (kappa = 0.804). The duct confluence was identified in all patients except four without an anomalous pancreaticobiliary ductal junction. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT for diagnosing an anomalous pancreaticobiliary ductal junction were 100% (9 of 9 patients), 87% (47 of 54 patients), 89% (56 of 63 patients), 75% (9 of 12 patients), and 100% (47 of 47 patients) in the final decisions, respectively. CT showed all associated pancreatobiliary diseases except bile duct stones in two patients. MDCT enabled the diagnosis of an anomalous pancreaticobiliary ductal junction by showing whether the pancreatic and biliary ducts join within the pancreatic parenchyma on high-resolution multiplanar reconstruction images.

Helical CT signs in the diagnosis of intestinal ischemia in small-bowel obstruction.

The purpose of our study was to determine prospectively the value of helical CT and of various signs of ischemia in the context of acute bowel obstruction. All patients seen over a 3-year period with a CT diagnosis of small-bowel obstruction were included. There were 144 examinations in 142 patients. Images were interpreted prospectively with consensus by a fellow and an experienced gastrointestinal radiologist. Attention was focused on the presence of the following signs of strangulation and ischemia: reduced enhancement of the small-bowel wall, mural thickening, mesenteric fluid, congestion of small mesenteric veins, and ascites. A diagnosis of ischemia was made if enhancement of the bowel wall was reduced or if at least two of the other signs were found. Results were correlated with surgical findings in 73 cases and clinical follow-up in 71 cases. A diagnosis of ischemia was made at surgery in 24 patients. CT diagnosis was correct in 23 patients (96% sensitivity). There were nine false-positive diagnoses (93% specificity). The negative predictive value of CT was 99%. Reduced enhancement of the bowel wall had a sensitivity of 48% and specificity of 100%, mural thickening had a sensitivity of 38% and specificity of 78%, mesenteric fluid had a sensitivity of 88% and specificity of 90%, congestion of mesenteric veins had a sensitivity of 58% and specificity of 79%, and ascites had a sensitivity of 75% and specificity of 76%. Helical CT is a highly sensitive method to diagnose or rule out intestinal ischemia in the context of acute small-bowel obstruction.

The Usefulness of Cystoscopy in the Staging of Cervical Cancer

Objective. The aim of this study was to clarify the usefulness of cystoscopy in the staging of cervical cancer and to evaluate the clinical indications for performing ureteric catheterization to rule out ureteral obstruction in cervical cancer.Methods. Both rigid cystoscopy and CT were performed before treatment in patients with cervical cancer of FIGO stage IB or greater. Cystoscopically directed biopsy specimens were taken from all areas in the bladder which were suspected of cancerous development. If a jet of urine spurting from each ureteral orifice was not found, a ureteric catheter was inserted into the orifice to rule out ureteral obstruction. The cystoscopic findings were compared with a CT examination.Results. A total of 100 patients were included in the study (mean age 59 years). There were 30 stage IB cancers, 20 stage IIA, 17 stage IIB, 5 stage IIIA, 18 stage IIIB, and 10 stage IV. A total of 90 patients had squamous cell carcinomas and 10 had adenocarcinomas. Cystoscopy identified 8 patients with bladder invasion including 1 stage IIIA, 2 stage IIIB, and 5 stage IV. All of these patients had CT indication of possible invasion. CT indication of possible invasion was proved to be false by cystoscopy in 2 patients. Both the sensitivity and the negative predictive value of CT for bladder invasion were 100%. Of the 14 patients in whom ureteral obstruction was diagnosed by ureteric catheterization, 11 cases were indicated by CT scan, but for the other 3 patients CT found no significant ureteral obstruction.Conclusions. The results of this study suggest that cystoscopy is indicated only in cervical cancer patients for whom CT examination indicates possible bladder invasion. In addition, the results suggest that placement of ureteric catheterization using cystoscopy to rule out ureteral obstruction is not indicated in the staging of cervical cancer.