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Brian C Lucey

Publications and source records attributed to Brian C Lucey.

At least 19 recordsLinked to original sources

Blunt abdominal trauma: utility of 5-minute delayed CT with a reduced radiation dose.

PURPOSE: To retrospectively evaluate the utility of 5-minute delayed computed tomography (CT) of the abdomen and pelvis by using a reduced radiation dose in patients with blunt abdominal trauma. MATERIALS AND METHODS: Institutional review board consent was obtained, and written informed consent was waived. The study was HIPAA compliant. A total of 662 patients (497 men, 165 women; mean age, 40.5 years; range, 18-94 years) were identified who were evaluated with CT after blunt abdominal trauma during a 1-year period. Delayed CT scans were acquired 5 minutes after intravenous contrast material injection by using a decreased tube current of 100 mAs. Injury was identified in 106 patients. Two radiologists blinded to initial CT scan interpretation reviewed these cases to determine the quality and utility of delayed scans. Disagreement was settled by consensus. Delayed scans were considered useful when they aided in (a) characterizing initial CT findings, (b) identifying findings not present at initial CT, (c) excluding injury suggested at initial CT, and (d) increasing reader confidence with regard to initial CT findings. RESULTS: All delayed scans were diagnostic. Delayed scans were useful in 27% (12 of 44) of patients with solid organ injury, 5.9% (one of 17) of patients with bowel or mesenteric injury, 4.5% (one of 22) of patients with pelvic fractures, and in none of the patients with free fluid only. Overall, delayed CT was useful in 2.1% (14 of 662) of all patients (95% confidence interval: 1.0, 3.2) referred for evaluation following blunt abdominal trauma. Utility increased to 13.2% (14 of 106) (95% confidence interval: 6.8, 19.7) in the group of patients with injury or suspected of having injury after initial CT. CONCLUSION: If delayed CT scans are acquired when patients with blunt abdominal trauma are evaluated, selective, rather than routine, acquisition is recommended and a reduced radiation dose seems adequate.

Abdominal Injuries↗

Perforated versus nonperforated acute appendicitis: accuracy of multidetector CT detection.

PURPOSE: To retrospectively evaluate the accuracy of multidetector computed tomography (CT) in the diagnosis of perforated acute appendicitis by using surgery and pathologic examination combined as the reference standard. MATERIALS AND METHODS: The study was institutional review board approved and HIPAA compliant. Informed patient consent was waived. The authors retrospectively identified 244 patients (150 male, 94 female; mean age, 32.8 years; age range, 4-83 years) with pathologically proved acute appendicitis who underwent abdominopelvic multidetector CT. Two radiologists reviewed in consensus the multidetector CT images obtained in all patients for various findings that may be associated with appendiceal perforation. For continuous variables, a comparison of means between the perforated and nonperforated groups was performed by using the Wilcoxon rank sum test. For categorical variables, the sensitivity and specificity of each CT finding for the diagnosis of perforated appendicitis were determined. RESULTS: The CT findings of abscess (99%), extraluminal gas (98%), and ileus (93%) had the highest specificities for appendiceal perforation; however, the sensitivities of these findings were low: 34%, 35%, and 53%, respectively. The appendix was larger in patients with perforated appendicitis: The mean diameter was 15.1 mm compared with a mean diameter of 11.7 mm in patients with nonperforated appendicitis (P < .001). Appendicolith, free fluid, enlarged abdominal lymph nodes, and enhancement defect in the appendiceal wall were neither highly sensitive nor highly specific for the detection of perforation. CONCLUSION: Although certain multidetector CT findings are very specific for the diagnosis of perforated appendicitis, overall multidetector CT sensitivity is poor. Unless abscess or extraluminal gas is present, multidetector CT cannot enable the diagnosis of perforation.

Acute Disease↗

Radiologic management of cysts in the abdomen and pelvis.

OBJECTIVE: Few abdominal or pelvic cystic lesions come to the attention of the interventional radiologist, and those that do are symptomatic. Differentiation of cysts from cystic-appearing masses is not difficult when a multitechnique imaging approach is used. Our objective is to summarize the principles and specifics for management of symptomatic cysts through percutaneous catheter techniques. CONCLUSION: Percutaneous aspiration of cysts can relieve symptoms without the need for surgery. A sound knowledge of the various types of cysts that may be found in the abdomen and pelvis enables the radiologist to select those patients who will benefit the most from percutaneous management.

Abdominal Cavity↗

Accuracy of MDCT in the diagnosis of choledocholithiasis.

OBJECTIVE: Our purpose was to evaluate the diagnostic performance of contrast-enhanced and unenhanced MDCT, performed for various indications, in detecting choledocholithiasis. CONCLUSION: Unenhanced and contrast-enhanced MDCT images, interpreted in PACS workstations with axial images, are moderately sensitive and specific for showing choledocholithiasis.

Adolescent↗

MRI of complicated pouchitis.

OBJECTIVE: The purpose of this study is to assess the ability of MRI to identify the presence of inflammation related to the pouch reservoir in symptomatic patients with an ileal pouch-anal anastomosis who present with clinically suspected complicated pouchitis. CONCLUSION: Initial results suggest that MRI should be considered in patients who have undergone ileal pouch-anal anastomosis and present a clinical impression of complicated pouchitis. MRI showed abnormalities consistent with complicated pouchitis in seven of nine examinations, with findings including pouch wall thickening, abnormal wall enhancement, peripouch fluid collection, sinus and fistula tract formation, lymphadenopathy, and peripouch stranding and fatty proliferation. MRI findings of complicated pouchitis should raise the suspicion of Crohn's disease and should prompt further investigation.

Adult↗

Posttraumatic bile leaks: role of diagnostic imaging and impact on patient outcome.

The aim of this study was to evaluate the impact of bile leaks on patient morbidity and hospital course following blunt and penetrating liver trauma. Forty patients who underwent hepatobiliary scintigraphy after trauma were included. Scintigraphic results were classified as follows: free intraperitoneal bile leak, contained bile leak, and no bile leak. Outcomes measured were length of hospital stay, number of procedures required, and number of subsequent imaging studies. Bile leaks were identified in 25% of patients. Eight percent had free intraperitoneal leaks, 18% contained bile leaks, and 73% had no bile leak. One study was nondiagnostic due to poor hepatic function. Mean hospitalization was as follows: free bile leak group, 53 days; contained bile leak group, 10 days; no bile leak group, 14 days. Patients with free intraperitoneal bile leak had more imaging studies and procedures than patients without free bile leak. Patients with liver injury and free intraperitoneal bile leak have longer hospitalizations and undergo more therapeutic procedures than those without, who respond to conservative management.

Adolescent↗

Distinguishing benign from malignant adrenal masses: multi-detector row CT protocol with 10-minute delay.

PURPOSE: To retrospectively evaluate the accuracy of precontrast attenuation, relative percentage washout (RPW), and absolute percentage washout (APW) in distinguishing benign from malignant adrenal masses at multi-detector row computed tomography (CT). MATERIALS AND METHODS: This HIPAA-compliant retrospective study had institutional review board approval; the need for informed consent was waived. One hundred twenty-two adrenal masses were evaluated in 99 patients (51 men, 48 women; age range, 37-86 years) who had undergone CT performed according to the study protocol and who either were given a pathologic diagnosis or underwent follow-up imaging. Unenhanced images were obtained before administration of 120 mL of an intravenous contrast agent with a 75-second scan delay. Delayed images were obtained after 10 minutes. RPW and APW were computed. Receiver operating characteristic (ROC) analysis was performed to compare mean attenuation and both RPW and APW. Analysis was first performed with the exclusion of pheochromocytomas, myelolipomas, and cysts. Precontrast attenuation criteria specific for benignity or malignancy were determined, and ROC analysis of results for the entire nonpheochromocytoma group was then performed. RESULTS: By using an RPW of 37.5% and excluding cysts and myelolipomas, all malignant lesions were detected with a sensitivity of 100% (17 of 17 lesions) and a specificity of 95% (90 of 95 lesions). Area under the binomial ROC curve (A(z)) values were 0.912, 0.985, and 0.892 for precontrast attenuation, RPW, and APW, respectively. Precontrast attenuation of less than 0 or more than 43 HU indicated benign and malignant entities, respectively. Incorporation of these criteria into the APW analysis yielded a sensitivity of 100% (17 of 17 lesions) and a specificity of 98% (93 of 95 lesions) for a threshold washout value of 52.0%. This attenuation-corrected APW generated the greatest A(z) value (ie, 0.988). Combining all the information available from the protocol yielded a sensitivity of 100% (17 of 17 lesions) and a specificity of 98% (98 of 100 lesions) for differentiating benign from malignant masses. CONCLUSION: Precontrast attenuation of less than 0 HU supercedes the washout profile in the evaluation of an individual adrenal mass. Noncalcified, nonhemorrhagic adrenal lesions with precontrast attenuation of more than 43 HU should be considered suspicious for malignancy.

Adrenal Gland Diseases↗

Pancreas divisum: depiction with multi-detector row CT.

PURPOSE: To retrospectively evaluate contrast material-enhanced multi-detector row computed tomography (CT) in the depiction of pancreas divisum. MATERIALS AND METHODS: This study was approved by the investigational review board. Seventy-seven patients (46 men and 31 women; mean age, 51 years) underwent CT with a four-detector row scanner and endoscopic retrograde pancreatography (ERP). Section thickness was 3.2 mm, and the reconstruction interval was 3 mm. Two radiologists independently evaluated the CT data sets with picture archiving and communication system (PACS) workstations equipped with software for two- and three-dimensional postprocessing reformations; the radiologists were blinded to the clinical and ERP data. Pancreas divisum was diagnosed at CT if what the authors termed the "dominant dorsal duct sign" (the caliber of the dorsal duct was larger than that of the ventral duct) was present and if the dorsal and ventral ducts did not appear to communicate with each other at cine review of images. ERP findings were used as the standard of reference for determining the performance (sensitivity, specificity, positive and negative predictive values) of the radiologists' CT interpretations. Interobserver agreement was measured by using kappa statistics. RESULTS: For four of the 77 patients (5%), both radiologists considered that depiction of the pancreatic duct on CT images was not sufficient to enable evaluation of ductal anatomy. These patients were excluded from further analysis. In the remaining 73 patients, ERP demonstrated pancreas divisum in 10 (14%); both observers made the correct diagnosis in nine of these patients. In addition, one radiologist had one false-positive interpretation, whereas the other radiologist had two false-positive interpretations. Thus, for observer 1, the calculated sensitivity was 90% (95% confidence interval [CI], 60%-98%) and the specificity was 98% (95% CI, 91%-100%). For observer 2, sensitivity was 90% (95% CI, 60%-98%) and specificity was 97% (95% CI, 89%-99%). Interobserver agreement was excellent (kappa = 0.93). CONCLUSION: CT scans obtained with multi-detector row scanners and interpreted with PACS workstations enable depiction of pancreas divisum. This assessment is possible only when the pancreatic duct is visualized.

Adolescent↗

Evaluation of blunt abdominal trauma using PACS-based 2D and 3D MDCT reformations of the lumbar spine and pelvis.

OBJECTIVE: The purpose of this study was to show the value of 2D and 3D reformations of CT data from abdominal and pelvic CT performed immediately at the workstation using a PACS-based software program to evaluate the lumbar spine and pelvis in patients with blunt abdominal trauma. MATERIALS AND METHODS: We reviewed the abdominopelvic CT scans and conventional radiographs of the lumbar spine or pelvis of 156 consecutive patients with blunt abdominal trauma. The CT data were compared with the radiographic findings and also with the findings of dedicated repeat CT of the spine or pelvis, when performed. RESULTS: CT depicted 80 fractures of the lumbar spine and 178 pelvic fractures. Radiography showed 40 fractures of the lumbar spine and 138 pelvic fractures. No additional fractures were identified on dedicated repeat CT. CONCLUSION: Conventional radiographs to clear the lumbar spine are no longer required when abdominopelvic CT data are available. CT and reformatted CT data show more fractures than radiography and miss no fractures compared with dedicated CT of the lumbar spine or pelvis. Having these images immediately available through the PACS workstation saves time for the trauma team in the management of critically ill patients.

Abdominal Injuries↗

Mesenteric lymph nodes: detection and significance on MDCT.

OBJECTIVE: Unsuspected mesenteric lymph nodes are frequently found on abdominal CT scans in everyday clinical practice. What to do with these findings has not been well established. The purpose of this study is to document the incidence of mesenteric lymph nodes in a previously healthy population and to provide guidelines for further management. MATERIALS AND METHODS: We examined the CT scans of 132 consecutive patients (84 men and 36 women; age range, 12-90 years; mean age, 43 years) who presented to the emergency department after experiencing blunt abdominal trauma. Twelve patients were excluded because they had disease processes known to be associated with lymphadenopathy. All imaging was performed using 3.2-mm collimation on MDCT scanners with IV contrast material. Two radiologists evaluated the images by consensus and recorded the presence of mesenteric lymph nodes greater than 3 mm in the short axis. Lymph node size, number, and location (central, peripheral, or right lower quadrant) were documented. All studies were reviewed on a PACS workstation. RESULTS: Of the 120 patients with otherwise normal CT scans, 47 had mesenteric lymph nodes greater than 3 mm. Of these 47 patients, 22 (47%) had five or more lymph nodes detected. Twenty-five (53%) of the 47 patients had four or fewer nodes. The mean size of the largest nodes was 4.8 mm (range, 3-9 mm), and the mean size of the nodes found per patient was 3.6 mm (range, 3-6 mm). These nodes were identified only at the mesenteric root in 32 patients (68%), only in the mesenteric periphery in eight patients (17%), and only in the right lower quadrant in five patients (11%). Nodes were identified in more than one location in two patients (4%). CONCLUSION: Incidental finding of mesenteric lymph nodes is common, reflecting more widespread use of thin-collimation MDCT and PACS workstations. In general, these nodes are small, measuring less than 5 mm. Such nodes when found in an otherwise healthy population are clinically insignificant and require no further imaging.

Adolescent↗

Blunt abdominal trauma: performance of CT without oral contrast material.

PURPOSE: To retrospectively evaluate multi-detector row computed tomography (CT) without oral contrast material for depiction of bowel and mesenteric injuries that require surgical repair in patients with blunt abdominal trauma. MATERIALS AND METHODS: The investigational review board approved the study. Informed consent was waived. CT reports for October 2001 to September 2003 were reviewed and 1082 patients were identified who had undergone abdominopelvic CT with a multi-detector row scanner and without oral contrast material. Findings were divided into four categories: negative, solid organ injury with or without hemoperitoneum, free fluid only, and suspected bowel or mesenteric injury. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated by comparing CT findings with laparotomy reports and hospital course. RESULTS: CT findings were no intraabdominal injury (n = 932), solid organ injury only (n = 102), free fluid only (n = 34), and suspected bowel or mesenteric injury (n = 14). CT findings in patients suspected of having bowel or mesenteric injury were pneumoperitoneum with other secondary findings (n = 4), mesenteric hematoma and bowel wall abnormality (n = 2), mesenteric hematoma only (n = 4), and bowel wall thickening only (n = 4). In 11 patients, bowel or mesenteric injury was proved surgically. Thus, the study included 1066 true-negative, nine true-positive, two false-negative, and five false-positive results. Based on these data, sensitivity was 82% (95% confidence interval [CI]: 52%, 95%), specificity was 99% (95% CI: 98%, 99%), positive predictive value was 64% (95% CI: 39%, 83%), and negative predictive value was 99% (95% CI: 98%, 99%) for depiction of bowel and mesenteric injuries. CONCLUSION: Multi-detector row CT without oral contrast material is adequate for depiction of bowel and mesenteric injuries that require surgical repair. Results are comparable with previously reported data for single-detector row helical CT with oral contrast material.

Abdominal Injuries↗

Acute pancreatitis: the role of imaging and interventional radiology.

Acute pancreatitis can manifest as a benign condition with minimal abdominal pain and hyperamylasemia or can have a fulminant course, which can be life-threatening usually due to the development of infected pancreatic necrosis, and multisystem organ failure. Fortunately, 70-80% of patients with acute pancreatitis have a benign self-limiting course (figs. 1, 2, 4). The initial 24-48 hours after the initial diagnosis is usually the period that determines the subsequent course, and for many of the 20-30% of patients who subsequently have a fulminant course, this becomes apparent within this time frame. With reference to long-term outcome following acute pancreatitis, most cases recover without long-term sequelae with only a minority of cases progressing to chronic pancreatitis. In the initial management of acute pancreatitis, assessment of metabolic disturbances and systemic organ dysfunction is critical. However, the advent and continued refinement of cross-sectional imaging modalities over the past two decades has led to a prominent role for diagnostic imaging in assessing acute pancreatitis. Furthermore, these cross-sectional imaging modalities have enabled the development of diagnostic and therapeutic interventional techniques in the hands of radiologists. In this article we review the diagnostic features of acute pancreatitis, the clinical staging systems, complications and the role of imaging. The role of interventional radiology techniques in the management of acute pancreatitis will be discussed as well as potential complications associated with these treatments.

Acute Disease↗

Haemolysis, elevated liver enzymes and low platelets syndrome: ultrasound and magnetic resonance imaging findings in the liver.

We describe the imaging findings of the HELLP (haemolysis, elevated liver enzymes and low platelets) syndrome in a gravid 36-year-old-woman who presented at 19.5 weeks gestation with severe right upper quadrant pain. Ultrasound findings suggested a focal hyperechoic liver lesion suggesting pregnancy-related hepatopathy prior to development of biochemical signs of HELLP syndrome. Within 3 days, the patient developed characteristic clinical and laboratory evidence of the HELLP syndrome. MR imaging at this time demonstrated localized hepatic ischaemia, further strengthening the diagnosis of HELLP syndrome.

Adult↗

Detection and characterization of lesions on low-radiation-dose abdominal CT images postprocessed with noise reduction filters.

PURPOSE: To assess the effect of noise reduction filters on detection and characterization of lesions on low-radiation-dose abdominal computed tomographic (CT) images. MATERIALS AND METHODS: Low-dose CT images of abdominal lesions in 19 consecutive patients (11 women, eight men; age range, 32-78 years) were obtained at reduced tube currents (120-144 mAs). These baseline low-dose CT images were postprocessed with six noise reduction filters; the resulting postprocessed images were then randomly assorted with baseline images. Three radiologists performed independent evaluation of randomized images for presence, number, margins, attenuation, conspicuity, calcification, and enhancement of lesions, as well as image noise. Side-by-side comparison of baseline images with postprocessed images was performed by using a five-point scale for assessing lesion conspicuity and margins, image noise, beam hardening, and diagnostic acceptability. Quantitative noise and contrast-to-noise ratio were obtained for all liver lesions. Statistical analysis was performed by using the Wilcoxon signed rank test, Student t test, and kappa test of agreement. RESULTS: Significant reduction of noise was observed in images postprocessed with filter F compared with the noise in baseline nonfiltered images (P =.004). Although the number of lesions seen on baseline images and that seen on postprocessed images were identical, lesions were less conspicuous on postprocessed images than on baseline images. A decrease in quantitative image noise and contrast-to-noise ratio for liver lesions was noted with all noise reduction filters. There was good interobserver agreement (kappa = 0.7). CONCLUSION: Although the use of currently available noise reduction filters improves image noise and ameliorates beam-hardening artifacts at low-dose CT, such filters are limited by a compromise in lesion conspicuity and appearance in comparison with lesion conspicuity and appearance on baseline low-dose CT images.

Adult↗

Enteric feeding with gastric decompression: management with separate gastric accesses.

OBJECTIVE: Our purpose is to describe our experience with combined enteral feeding and gastric decompression or drainage in debilitated patients with persistent gastroesophageal reflux using two separate catheters. CONCLUSION: The placement of two percutaneous catheters through separate skin sites is a feasible and successful approach to providing enteral feeding and gastric decompression or drainage in debilitated patients with persistent gastroesophageal reflux and aspiration pneumonia.

Adolescent↗