Association of visceral adiposity with oesophageal and junctional adenocarcinomas

BACKGROUND

Obesity is associated with an increased incidence of oesophageal and oesophagogastric junction adenocarcinoma, in particular Siewert types I and II. This study compared abdominal fat composition in patients with oesophageal/junctional adenocarcinoma with that in patients with oesophageal squamous cell carcinoma and gastric adenocarcinoma, and in controls.

METHOD

In total, 194 patients (110 with oesophageal/junctional adenocarcinoma, 38 with gastric adenocarcinoma and 46 with oesophageal squamous cell carcinoma) and 90 matched control subjects were recruited. The abdominal fat area was assessed using computed tomography (CT), and the total fat area (TFA), visceral fat area (VFA) and subcutaneous fat area (SFA) were calculated.

RESULTS

Patients with oesophageal/junctional adenocarcinoma had significantly higher TFA and VFA values compared with controls (both P < 0.001), patients with gastric adenocarcinoma (P = 0.013 and P = 0.006 respectively) and patients with oesophageal squamous cell carcinoma (both P < 0.001). For junctional tumours, the highest TFA and VFA values were seen in patients with Siewert type I tumours (respectively P = 0.041 and P = 0.033 versus type III; P = 0.332 and P = 0.152 versus type II).

CONCLUSION

Patients with oesophageal/junctional adenocarcinoma, in particular oesophageal and Siewert type I junctional tumours, have greater CT-defined visceral adiposity than patients with gastric adenocarcinoma or oesophageal squamous cell carcinoma, or controls.

Clinical Immunology Review Series: an approach to the patient with recurrent orogenital ulceration, including Behçet's syndrome

Patients presenting with recurrent orogenital ulcers may have complex aphthosis, Behçet's disease, secondary complex aphthosis (e.g. Reiter's syndrome, Crohn's disease, cyclical neutropenia) or non-aphthous disease (including bullous disorders, erythema multiforme, erosive lichen planus). Behçet's syndrome is a multi-system vasculitis of unknown aetiology for which there is no diagnostic test. Diagnosis is based on agreed clinical criteria that require recurrent oral ulcers and two of the following: recurrent genital ulcers, ocular inflammation, defined skin lesions and pathergy. The condition can present with a variety of symptoms, hence a high index of suspicion is necessary. The most common presentation is with recurrent mouth ulcers, often with genital ulcers; however, it may take some years before diagnostic criteria are met. All patients with idiopathic orogenital ulcers should be kept under review, with periodic focused assessment to detect evolution into Behçet's disease. There is often a delay of several years between patients fulfilling diagnostic criteria and a diagnosis being made, which may contribute to the morbidity of this condition. Despite considerable research effort, the aetiology and pathogenesis of this condition remains enigmatic.

Sweet's syndrome in association with common variable immunodeficiency

Sweet's syndrome (SS), a rare reactive neutrophilic dermatosis, has been reported to occur in association with a variety of systemic disorders, categorized by von den Diesch into idiopathic, paraneoplastic, pregnancy and parainflammatory subgroups. The parainflammatory group has been well defined, and includes a wide spectrum of infectious triggers and disorders of immune dysregulation. To date, however, no cases of SS have been described in the context of common variable immunodeficiency (CVID). We report a case of paediatric-onset SS, previously reported as idiopathic, with a subsequent diagnosis of CVID.

An unusual case of Behçet's syndrome: triggered by typhoid vaccination?

A case of Behçet's syndrome in a 32-year-old woman occurring shortly after her third vaccination against typhoid fever is described. Scleritis and pyoderma gangrenosum were unusual manifestations of BS that occurred in this case. Treatment benefit was provided by mycophenolate mofetil and etanercept. As bacterial antigens have been proposed as potential triggers for the onset of BS, it is possible that the syndrome was precipitated by typhoid vaccination in this patient.

Multiphase contrast-enhanced helical CT of liver metastases from renal cell carcinoma

The aim of this study was to evaluate whether in patients with metastatic renal cell carcinoma (RCC) multiphase liver studies would improve detection of metastatic liver disease. Forty-six consecutive patients with known metastatic RCC underwent standardized non-contrast and triphasic contrast enhanced hepatic CT examinations as part of their routine imaging studies. Once a liver abnormality was detected, it was characterized as metastatic by a panel of three radiologists who followed pre-set criteria. These criteria included change in size, biopsy results and lack of benign features. Presence and conspicuity of liver metastases were graded using a five-point scale by consensus of a panel of three radiologists. The highest number of lesions evaluated per patient was limited to ten. Seventy-two liver metastases were detected in 16 patients. Of these, 54 were seen on unenhanced scans; 47 in the hepatic arterial (HA) phase, at 25 s; 65 in the portal-venous (PV) phase, at 60 s; and 49 in delayed images, at 90 s. Scanning only during the PV phase would have missed seven lesions (10%), six of which were seen on unenhanced images and six were seen in HA phase. All patients with metastatic liver disease would have been identified by combination of unenhanced and PV phase or by HA and PV phase scanning. Forty-two lesions were graded more conspicuous on the PV phase, whereas 18 (25%) were more conspicuous on the HA phase. The combination of unenhanced, HA and PV scanning should be considered in the initial evaluation of patients with metastatic RCC for improved lesion detection and characterization. Subsequently, the combination of unenhanced and PV phase imaging is preferred.

Staging of pancreatic cancer before and after neoadjuvant chemoradiation

Neoadjuvant chemoradiation therapy is used at many institutions for treatment of localized adenocarcinoma of the pancreas. Accurate staging before neoadjuvant therapy identifies patients with distant metastatic disease, and restaging after neoadjuvant therapy selects patients for laparotomy and attempted resection. The aims of this study were to (1) determine the utility of staging laparoscopy in candidates for neoadjuvant therapy and (2) evaluate the accuracy of restaging CT following chemoradiation. Staging laparoscopy was performed in 98 patients with radiographically potentially resectable (no evidence of arterial abutment or venous occlusion) or locally advanced (arterial abutment or venous occlusion) adenocarcinoma of the pancreas. Unsuspected distant metastasis was identified in 8 (18%) of 45 patients with potentially resectable tumors and 13 (24%) of 55 patients with locally advanced tumors by CT. Neoadjuvant chemoradiation therapy and restaging CT were completed in a total of 103 patients. Thirty-three patients with potentially resectable tumors by restaging CT underwent surgical exploration and resections were performed in 27 (82%). Eleven (22%) of 49 patients with locally advanced tumors by restaging CT were resected, with negative margins in 55%; the tumors in these 11 patients had been considered locally advanced because of arterial involvement on restaging CT. Staging laparoscopy is useful for the exclusion of patients with unsuspected metastatic disease from aggressive neoadjuvant chemoradiation protocols. Following neoadjuvant chemoradiation, restaging CT guides the selection of patients for laparotomy but may overestimate unresectability to a greater extent than does prechemoradiation CT.

Technologic advances in abdominal MR imaging

Magnetic resonance (MR) imaging is finding an ever-growing role in the evaluation of a wide range of conditions in the abdomen. No longer confined to problem solving regarding abnormalities in solid organs, such as the liver and kidneys, MR imaging is increasingly being applied to the evaluation of the pancreatic and biliary ductal systems and even the bowel. Recent technical advances in hardware and software have allowed the acquisition of MR images that are largely free of artifact secondary to bowel peristalsis or respiratory motion; images providing excellent anatomic detail can now be obtained routinely. Faster sequences have reduced image acquisition time, thereby improving patient acceptance and allowing more efficient utilization of machine time. New three-dimensional sequences allow rapid image acquisition, reducing section misregistration and motion artifact while improving multiplanar reformations. The potential of MR imaging to provide functional and anatomic information is intriguing, and new techniques, including diffusion and perfusion imaging, are being evaluated. This review considers the advances in imaging hardware and pulse sequence design that underlie the increasing role of MR imaging in evaluation of the abdomen and discusses evolving clinical applications.

Two-dimensional multiplanar and three-dimensional volume-rendered vascular CT in pancreatic carcinoma: interobserver agreement and comparison with standard helical techniques

OBJECTIVE

The purpose of this study was to compare two-dimensional curved multiplanar and three-dimensional reconstructions, routine axial presentations, and combined techniques in the assessment of vascular involvement by pancreatic malignancy.

MATERIALS AND METHODS

For 44 patients with known pancreatic malignancy a total of 56 arterial phase helical CT scans were obtained. Targeted pancreatic imaging was performed, and reformatted images were generated. Axial source images, reformatted images, and the combination of axial and reformatted images were interpreted independently by three observers. The observers graded the celiac axis, common and proper hepatic, splenic, gastroduodenal, and superior mesenteric arteries for tumor involvement. Grades of vascular involvement were compared by intra- and interobserver variability analyses.

RESULTS

Intraobserver agreement averaged over five vessels was good between the axial and combined techniques for each individual observer (0.64 < or kappa < or = 0.66), but intraobserver agreement was poor between the axial and reformatted (kappa = 0.17 and kappa = 0.31, respectively) and the reformatted and combined techniques (kappa = 0.31 and kappa = 0.38, respectively) for two observers. For grading of vascular involvement in each vessel, intraobserver agreement was good to excellent between the axial and combined techniques (0.48 or = kappa < or = 0.82). Interobserver agreement averaged over five vessels was poor for imaging techniques except between observer 2 and observer 3 on the axial (kappa = 0.47) and combined techniques (kappa = 0.47). For grading of vascular involvement in each vessel, interobserver agreement for reformatted technique was poor (0.09 < or = kappa < or = 0.40).

CONCLUSION

Multiplanar and volume-rendered techniques showed the highest intra- and interobserver variability in grading vascular involvement by pancreatic malignancy. These images should be used in combination with routine axial images to decrease observer variability.

Impact of multidetector CT on donor selection and surgical planning before living adult right lobe liver transplantation

OBJECTIVE

This study was performed to document the impact of multidetector multiphase CT in facilitating patient selection and surgical planning in potential donors being evaluated for living adult right lobe liver transplantation.

SUBJECTS AND METHODS

Forty consecutive potential donors were included in the study. There were 26 men and 14 women, (age range, 18-57 years; mean, 37 years) We performed CT using a multidetector scanner, after IV injection of 180 mL of contrast material at 5 mL/sec. Arterial phase images were acquired at 18 sec (collimation, 1.25 mm; table speed, 7.5) and portal phase images, at 60 sec (collimation, 2.5 mm; table speed, 15). Postprocessing was performed on a commercially available workstation. CT data included dual-energy assessment of liver parenchyma for fatty infiltration; depiction of arterial, portal venous, and hepatic venous anatomy and identification of important vascular variants; and determination of total and lobar liver volume.

RESULTS

Of the 40 potential liver donors evaluated, 15 patients (37.5%) were excluded on the basis of CT findings, with most exclusions a result of portal vein anomalies (n = 8). Fatty infiltration resulted in four exclusions (10%), and small liver volume resulted in three exclusions (7.5%).

CONCLUSION

Multidetector multiphase CT provided comprehensive parenchymal, vascular, and volumetric preoperative evaluation of potential donors undergoing living adult right lobe liver transplantation. This information had a major impact on patient selection because it was used to stratify patients. It allowed the surgeons to plan their surgical approach, and this planning may reduce postoperative complications.

Nonenhanced helical CT and US in the emergency evaluation of patients with renal colic: prospective comparison

PURPOSE

To compare nonenhanced helical computed tomography (CT) with ultrasonography (US) for the depiction of urolithiasis.

MATERIALS AND METHODS

During 9 months, 45 patients (mean age, 44 years; mean weight, 92.5 kg) prospectively underwent both nonenhanced helical CT (5-mm collimation; pitch of 1.5) and US of the kidneys, ureters, and bladder. US evaluation included a careful search for ureteral calculi. Presence of calculi and obstruction and incidental diagnoses were recorded. Clinical, surgical, and/or imaging follow-up data were obtained in all patients. The McNemar test was used to compare groups.

RESULTS

Diagnoses included 23 ureteral calculi and one each of renal cell carcinoma, appendicitis, ureteropelvic junction obstruction, renal subcapsular hematoma, cholelithiasis, medullary calcinosis, and myelolipoma. CT depicted 22 of 23 ureteral calculi (sensitivity, 96%). US depicted 14 of 23 ureteral calculi (sensitivity, 61%). Differences in sensitivity were statistically significant (P: =.02). Specificity for each technique was 100%. When modalities were compared for the detection of any clinically relevant abnormality (eg, unilateral hydronephrosis and/or urolithiasis in patients with an obstructing calculus), sensitivities of US and CT increased to 92% and 100%, respectively. One case of appendicitis was missed at US, whereas medullary calcinosis and myelolipoma were missed at CT.

CONCLUSION

Nonenhanced CT has a higher sensitivity for the detection of ureteral calculi compared with US.

Right lower quadrant pain and suspected appendicitis: nonfocused appendiceal CT--review of 100 cases

PURPOSE

To determine the value of standard, nonfocused computed tomography (CT) in examining patients with right lower quadrant (RLQ) pain and suspected appendicitis.

MATERIALS AND METHODS

The CT scans and medical records of 100 consecutive patients who presented to the emergency department with RLQ pain and were clinically suspected of having appendicitis were retrospectively reviewed. Helical CT of both the abdomen and pelvis was performed at 7-mm increments after oral and intravenous contrast material administration. CT scans were evaluated for the presence of appendiceal or other disease. Results were correlated with surgical and pathologic findings in 34 patients or with 3-month clinical follow-up in 66 patients.

RESULTS

CT depicted abnormalities in 66 patients (66%). In 59 (59%) patients, the abnormality was located in the pelvis; 23 (39%) of these patients had appendicitis. Seven (7%) patients had abnormalities outside of the pelvis, a region not typically scanned during focused appendiceal imaging. Four of these seven patients required surgery. Thus, if only pelvic focused RLQ CT had been performed, overall sensitivity would have decreased from 99% to 88% (P <.05) and sensitivity for cases necessitating surgery would have decreased from 96% to 82% (P <.05).

CONCLUSION

Both abdominal and pelvic CT examinations are necessary to increase sensitivity and identify the many possible causes of RLQ pain in patients with clinically suspected appendicitis.

An investigation into causative factors in patients with bronchiectasis

Bronchiectasis is a pathologic description of lung damage characterized by inflamed and dilated thick-walled bronchi. These findings may result from a number of possible causes and these may influence treatment and prognosis. The aim of this study was to determine causative factors in 150 adults with bronchiectasis (56 male, 94 female) identified using high-resolution computerized tomography. Relevant factors were identified in the clinical history; cystic fibrosis gene mutation analysis was performed; humoral immune defects were determined by measuring immunoglobulins, IgG subclasses and functional response to Pneumovax II vaccine; assessment was made of neutrophil function (respiratory burst, adhesion molecule expression, and chemotaxis); ciliary function was observed and those likely to have allergic bronchopulmonary aspergillosis (ABPA) were identified. Causes identified were: immune defects (12 cases), cystic fibrosis (4), Young's syndrome (5), ciliary dysfunction (3), aspiration (6), panbronchiolitis (1), congenital defect (1), ABPA (11), rheumatoid arthritis (4), and early childhood pneumonia, pertussis, or measles (44). Intensive investigation of this population of patients with bronchiectasis led to identification of one or more causative factor in 47% of cases. In 22 patients (15%), the cause identified had implications for prognosis and treatment.

MR cholangiopancreatography of bile and pancreatic duct abnormalities with emphasis on the single-shot fast spin-echo technique

Magnetic resonance cholangiopancreatography (MRCP) is used for noninvasive work-up of patients with pancreaticobiliary disease. MRCP is comparable with invasive endoscopic retrograde cholangiopancreatography (ERCP) for diagnosis of extrahepatic bile duct abnormalities. In patients with choledocholithiasis, calculi appear as dark filling defects within the high-signal-intensity fluid at MRCP. Benign strictures due to sclerosing cholangitis are multifocal and alternate with slight dilatation or normal-caliber bile ducts, producing a beaded appearance. Dilatation of both the pancreatic and bile ducts at MRCP is highly suggestive of a pancreatic head malignancy. Side-branch ectasia is the most prominent and specific feature of chronic pancreatitis. MRCP is more sensitive than ERCP in detection of pancreatic pseudocysts because less than 50% of pseudocysts fill with contrast material. Because the mucin secreted by biliary cystadenomas and cystadenocarcinomas causes filling defects and partial obstruction of contrast material at ERCP, MRCP is potentially more accurate in demonstrating the extent of these tumors. In patients with biliary-enteric anastomoses, MRCP is the imaging modality of choice for the work-up of suspected pancreaticobiliary disease. A potential use of MRCP is the demonstration of aberrant bile duct anatomy before cholecystectomy. MRCP is also accurate in detection of pancreas divisum.

Radiologic manifestations of sclerosing cholangitis with emphasis on MR cholangiopancreatography

Magnetic resonance cholangiopancreatography (MRCP) is a relatively new, noninvasive cholangiographic technique that is comparable with invasive endoscopic retrograde cholangiopancreatography (ERCP) in the detection and characterization of extrahepatic bile duct abnormalities. The role of MRCP in evaluation of the intrahepatic bile ducts, especially in patients with primary or secondary sclerosing cholangitis, is under investigation. The key cholangiographic features of primary sclerosing cholangitis are randomly distributed annular strictures out of proportion to upstream dilatation. As the fibrosing process worsens, strictures increase and the ducts become obliterated, and the peripheral ducts cannot be visualized to the periphery of the liver at ERCP. In addition, the acute angles formed with the central ducts become more obtuse. With further progression, strictures of the central ducts prevent peripheral ductal opacification at ERCP. Cholangiocarcinoma occurs in 10%-15% of patients with primary sclerosing cholangitis; cholangiographic features that suggest cholangiocarcinoma include irregular high-grade ductal narrowing with shouldered margins, rapid progression of strictures, marked ductal dilatation proximal to strictures, and polypoid lesions. Secondary sclerosing and nonsclerosing processes can mimic primary sclerosing cholangitis at cholangiography. These processes include ascending cholangitis, oriental cholangiohepatitis, acquired immunodeficiency syndrome-related cholangitis, chemotherapy-induced cholangitis, ischemic cholangitis after liver transplantation, eosinophilic cholangitis, and metastases.

Radiology of urinary diversions

Radiologic evaluation of urinary diversion has three objectives: to monitor upper tract distention, to detect new urothelial tumors and to detect metastasis. The type of imaging procedure and the frequency of imaging is dictated by the urologist preference. As many surgical procedures are available for noncontinent and continent diversion, interpretation of radiographic studies requires a detailed knowledge of the type of surgical procedure that has been performed.

Percutaneous CT-guided biopsy: improved confirmation of sampling site and needle positioning using a multistep technique at CT fluoroscopy

We describe a new multistep procedure for CT fluoroscopy-guided core biopsy, which allows confirmation of the biopsy-sampling trough and the final needle tip position prior to sampling. Twelve lesions measuring < or =2 cm or in close proximity to vital structures were biopsied using commercially available biopsy systems. Diagnostic biopsies were obtained in all cases. Mean fluoroscopy time was 11.1 +/- 2.8 s per biopsy. This technique may have the potential to improve the accuracy and safety of CT-guided biopsy.

Vaccines for preventing infection with Pseudomonas aeruginosa in people with cystic fibrosis

OBJECTIVES

To assess the effectiveness of vaccination against Pseudomonas aeruginosa in patients with cystic fibrosis.

SEARCH STRATEGY

The Cochrane Cystic Fibrosis and Genetic Disorders Group specialist trials register which comprises references identified from comprehensive electronic database searches, handsearching relevant journals and handsearching abstract books of conference proceedings. Date of the most recent search of the Group's specialised register: November 1999.

SELECTION CRITERIA

All randomised or pseudorandomised trials (published or unpublished) comparing Pseudomonas aeruginosa vaccines (oral, parenteral or intranasal) with control vaccines or no intervention in patients with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

We planned to assess the following outcomes: time to infection with Pseudomonas aeruginosa, pulmonary function, body mass index, Schwachman score, frequency of pulmonary infective exacerbations, days of antibiotic usage, days unable to carry out normal daily activities, adverse events, mortality, antibody levels to Pseudomonas aeruginosa and T cell proliferation and cytokine production in response to Pseudomonas aeruginosa.

MAIN RESULTS

One trial which included 17 vaccinated patients, with follow up reported to 10 years met the inclusion criteria. Finding only a single trial, and the lack of information on our predefined outcomes limited analysis.

REVIEWER'S CONCLUSIONS

There is a paucity of randomised controlled trials assessing the effectiveness of vaccination against Pseudomonas aeruginosa in cystic fibrosis. Increased understanding of modulation of the immune response by vaccination has led to the development of alternative vaccines. We suggest that there is an urgent need for newer vaccines to be evaluated in adequately-powered, multicentre randomised controlled trials examining clinically relevant end-points in addition to immunological variables. Such a trial should assess effectiveness over several years, and include follow-up of vaccinees who become colonised with Pseudomonas aeruginosa.

Pancreatitis complicated by gland necrosis: evolution of findings on contrast-enhanced CT

PURPOSE

The purpose of this work was to investigate the natural history of pancreatic necrosis on contrast-enhanced CT in patients managed nonoperatively.

METHOD

A computer-based radiology information search revealed 32 patients with pancreatic necrosis who had had serial contrast-enhanced CT scans and were managed nonoperatively. There were 23 men and 9 women with a mean age of 51 years. One hundred forty-five contrast-enhanced CT scans were retrospectively reviewed for the location and extent of necrosis. The medical records of all patients were reviewed.

RESULTS

The 32 patients had a mean Ranson clinical grade of 5.8 (range 3-8). Eighteen of these 32 patients were managed nonoperatively, and 14 patients required a necrosectomy after initial nonoperative management. In the 32 patients, the location of necrosis was in the head (3), body (6), tail (2), head/body (2), head/body/tail (9), body/tail (9), and head/tail (1). Extent of necrosis was 0-25% (9), 26-50% (6), 51-75% (6), and 76-100% (11). The extent of necrosis remained stable during follow-up in 22 (69%) patients and increased during follow-up in 10 (31%). Necrosectomy was performed in six (60%) patients in whom there was an increase in necrosis and eight (36%) patients in whom necrosis was stable. No patient had restoration of normal enhancement in an area that was previously necrotic. There were five patients who were managed nonoperatively (mean follow-up 318 days) in whom the necrosis eventually resorbed, forming a focal parenchymal cleft reminiscent of a scar. Five of the 32 patients died.

CONCLUSION

Pancreatic necrosis as demonstrated by CT tends to remain stable in most patients treated nonoperatively. If the extent of necrosis increases, patients are more likely to require a necrosectomy. In some patients managed nonoperatively, the pancreatic necrosis will resorb, resulting in a fat-replaced cleft reminiscent of a scar.

Lung cancer staging and management: comparison of contrast-enhanced and nonenhanced helical CT of the thorax

PURPOSE

To determine whether contrast material-enhanced helical computed tomography (CT) of the thorax and upper abdomen changes the tumor stage and management compared with nonenhanced helical CT in patients with newly diagnosed lung cancer.

MATERIALS AND METHODS

During 15 months, any patient in whom lung cancer was strongly suspected or newly diagnosed and who was scheduled for thoracic CT was considered eligible for the study. All patients underwent nonenhanced thoracic helical CT from the lung apices through the adrenal glands and then contrast-enhanced thoracic helical CT from the lung apices through the entire liver. Each study was read independently, and the thoracic radiologic stage was determined. Tissue sampling was performed and the final pathologic stage assigned.

RESULTS

Ninety-six patients had a final pathologic diagnosis of lung cancer. There was agreement in stage between the nonenhanced and contrast-enhanced examinations in 92 of the 96 patients. In three patients, the tumor stage at nonehanced CT increased at contrast-enhanced CT, from IA to IIA (n = 1), IIB to IV (n = 1), and IIIB to IV (n = 1). In one patient, the tumor stage decreased from IIIB to IIB. There was no substantial change in management of any patient.

CONCLUSION

The results suggest that contrast-enhanced thoracic CT through the liver for staging lung cancer rarely changes the tumor stage determined with nonenhanced CT through the adrenal glands and does not substantially influence management decisions.

Comparison of unenhanced, hepatic arterial-dominant, and portal venous-dominant phase helical CT for the detection of liver metastases in women with breast carcinoma

OBJECTIVE

The purpose of this study was to evaluate triple-phase helical CT for detection of hepatic metastases from breast carcinoma.

SUBJECTS AND METHODS

Breast cancer patients were studied prospectively with triple-phase helical CT in 300 consecutive examinations. Hepatic arterial-dominant and portal venous-dominant phase scans were initiated at 20 and 65 sec, respectively, after IV injection of 175 ml of iopamidol (30 mg/ml) at 5 ml/sec. Three independent observers each reviewed 200 cases of the portal venous-dominant phase for lesion number, conspicuity, and attenuation. Subsequently, portal venous-dominant phase images were reevaluated in conjunction with hepatic arterial-dominant phase or unenhanced images.

RESULTS

Hepatic metastases were identified in 79 (26%) of 300 cases. Lesions detected on portal venous-dominant, hepatic arterial-dominant, and unenhanced images were as follows: observer 1, n = 198, 164, and 171; observer 2, n = 254, 233, and 233; and observer 3, n = 291, 270, and 276 (p > .05). The mean total lesion count was 387, with more lesions detected on portal venous-dominant phase than on either hepatic arterial-dominant phase or unenhanced images (p < .001 and p < .0001, respectively). For individual observers, 10-26% of lesions were hypervascular on hepatic arterial-dominant phase images. Two to 4% of lesions were identified only on hepatic arterial-dominant phase or unenhanced images. However, in these few cases, the lesions either were false-positives or were seen in conjunction with additional metastases on portal venous-dominant images.

CONCLUSION

Routine use of triple-phase CT in patients with breast carcinoma may not be warranted: Addition of the hepatic arterial-dominant phase or unenhanced images revealed few additional lesions in our group of 300 patients.

Imaging-guided percutaneous biopsy of focal splenic lesions: update on safety and effectiveness

OBJECTIVE

The purpose of this study is to determine the safety and effectiveness of percutaneous imaging-guided biopsy in the diagnosis of focal splenic lesions.

MATERIALS AND METHODS

From May 1995 to November 1997, 20 imaging-guided biopsies of focal splenic lesions were performed in 18 patients, including seven patients with a prior diagnosis of extrasplenic malignancy (breast cancer, n = 3; lymphoma, n = 2; ovarian cancer, n = 1; and osteogenic sarcoma, n = 1), three immunosuppressed patients (cause of immunosuppression: AIDS, n = 1; liver transplantation, n = 1; and bone marrow transplantation, n = 1), two patients with anemia, one patient with a recent history of IV drug abuse, and five patients with incidentally discovered splenic lesions. Biopsies were performed with an 18-gauge (n = 1), a 20-gauge (n = 8), or a 22-gauge (n = 14) self-aspirating needle or an 18-gauge cutting needle (n = 1). Biopsies were considered successful if a specific diagnosis of benign or malignant disease was made.

RESULTS

A specific diagnosis was made in 16 (88.9%) of 18 patients, and no complications occurred. Malignancy was diagnosed in six patients including three patients with lymphoma. Benign conditions were diagnosed in 10 patients: a cyst in two patients; hamartoma in one; lipogranuloma in one; infarct in one; and infection in four, including one case each of Candida albicans, Pneumocystis carinii, Mycobacterium tuberculosis, and mixed flora. The tenth benign diagnosis was a pseudotumor of the spleen related to a bulbous tail of the pancreas that was inseparable from the splenic hilum. Biopsy did not establish a diagnosis in one patient with lymphoma and in one patient with presumed splenic candidiasis. A mean of 1.5 needle passes was made per biopsy.

CONCLUSION

Imaging-guided splenic biopsy is a safe technique that provides a specific diagnosis in most patients with focal splenic lesions.

Pancreatic transplantation using portal venous and enteric drainage: the postoperative appearance of a new surgical procedure

PURPOSE

To review the normal radiologic appearance of pancreatic transplants that use portal venous and enteric drainage, and to review the appearance of a variety of postoperative complications.

METHOD

We retrospectively reviewed the computed tomographic (CT) scans, magnetic resonance (MR) images, and ultrasounds of patients who had undergone pancreatic transplantation using portal venous and enteric drainage.

RESULTS

At CT, the normal pancreatic transplant appears as a heterogeneous mass composed of pancreatic parenchyma, vessels, and omental wrap. On MR imaging, a normal transplant demonstrates intermediate signal intensity on T1- and T2-weighted sequences. Sonographic evaluation of a normal transplant reveals a hypoechoic gland that contains readily detectable low-resistance arterial and venous Doppler waveforms. Acute postoperative complications include acute rejection, which has a nonspecific radiologic appearance, and transplant pancreatitis, which is often manifested on CT by stranding of the peritransplant fat. Chronic postoperative complications include small bowel obstructions, graft pancreatitis secondary to obstruction of the Roux loop, and chronic rejection.

CONCLUSION

Knowledge of the radiologic appearance of the normal pancreatic transplant is required before transplant-related complications can be detected.

Diagnosis of pancreatic carcinoma: role of FDG PET

OBJECTIVE

The purpose of this study was to investigate the role of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in differentiating benign from malignant disease in patients with possible pancreatic malignancy.

SUBJECTS AND METHODS

All patients with a possible diagnosis of pancreatic carcinoma based on CT or ERCP findings were eligible for inclusion in this prospective study. PET imaging of the abdomen was performed in 37 patients and was interpreted as positive if FDG activity in the pancreas exceeded background activity and as negative if activity was less than or equal to background activity. Semiquantitative analysis was performed by calculating a standardized uptake ratio. Studies were reviewed independently by two radiologists, and results were correlated with biopsy results and with CT and ERCP findings. Sensitivity and specificity of FDG PET for revealing pancreatic malignancy was determined.

RESULTS

FDG activity in the pancreas was increased in 24 patients, and adenocarcinoma was diagnosed in 22 of these patients (92%). Two patients (8%) with increased activity had benign disease, including one patient with chronic pancreatitis who showed no evidence of tumor at laparotomy and one patient with a mucinous cystic tumor who showed no malignant features at laparotomy. FDG uptake was low or normal in 13 patients, 10 of whom (77%) had benign disease. FDG uptake was also low in three patients with adenocarcinoma, whose tumor size ranged from 2 to 4 cm in diameter. The mean standardized uptake ratio value for malignant disease was 5.1 (range, 1.0-10.1) and for benign disease was 1.9 (range, 0.0-5.8) (p < .001). The sensitivity of FDG PET for revealing malignant disease in the pancreas was 88% and the specificity was 83%.

CONCLUSION

FDG PET is a sensitive and specific noninvasive technique for the diagnosis of pancreatic malignancy.

Interobserver variability in the interpretation of unenhanced helical CT for the diagnosis of ureteral stone disease

PURPOSE

The purpose of this study was to analyze interobserver agreement in the interpretation of unenhanced helical CT (UHCT) for the evaluation of ureteral stone disease and obstruction.

METHOD

One hundred three UHCT examinations were independently and retrospectively reviewed by five readers including attending radiologists, a radiology resident, and an attending urologist. Examinations were interpreted as positive, negative, or indeterminate for ureteral stone disease and obstruction. The Cohen kappa test was used to measure interobserver agreement. The accuracy of the readers was also assessed.

RESULTS

The kappa value ranged from 0.67 to 0.71 among the three attending radiologists and from 0.65 to 0.67 among the radiology attending physicians and radiology resident. Although the urologist tended to agree less well with the other readers (kappa range: 0.33-0.46), there was no statistically significant difference (p < 0.05) in the accuracy among all five readers. The percentage of cases interpreted as indeterminate ranged from 8 to 25% and almost invariably involved difficulty distinguishing phleboliths from minimally obstructing distal ureteral calculi. The percentage of UHCT scans correctly interpreted as positive and correctly interpreted as negative ranged from 73% (n = 27) to 86% (n = 32) and 63% (n = 22) to 86% (n = 30), respectively.

CONCLUSION

Interobserver agreement was very good among the radiology attending physicians and resident and moderate with the urologist. The examination is an accurate technique in the evaluation of ureteral stone disease, although limitations exist, particularly in the diagnosis of minimally obstructing distal ureteral calculi.

Dynamic helical CT of the abdomen: prospective comparison of pre- and postprandial contrast enhancement

PURPOSE

To investigate effects of a liquid meal on contrast material enhancement at dynamic helical computed tomography (CT).

MATERIALS AND METHODS

Twenty healthy, fasting subjects underwent intravenous injection of nonionic contrast material at 4 mL/sec. Axial CT sections were obtained at a single level 15 seconds after injection, then every 5 seconds for 2 minutes. This protocol was repeated 1 week later, after ingestion of a 360-calorie liquid meal. Hepatic, splenic, and aortic attenuation were measured before and after contrast material administration. Peak enhancement level, time to peak enhancement, slope of hepatic enhancement, and hepatic, splenic, and aortic enhancement ratios were determined.

RESULTS

Postprandial time to peak enhancement was 4.4 seconds earlier than preprandial (59.6 seconds +/- 9.0 [1 standard deviation] vs 64.0 seconds +/- 9.5; P < .02). No differences in maximum attenuation were found (P > .27). Postprandial maximum slope of hepatic enhancement and temporal and quantitative enhancement characteristics in aorta and spleen did not significantly differ. Postprandial hepatic-to-splenic enhancement ratios increased (P = .04), and aortic-to-hepatic ratios decreased (P = .01). Aortic-to-splenic ratios did not differ (P = .45).

CONCLUSION

A liquid meal before intravenous injection of contrast material produces more rapid peak hepatic enhancement, with slightly increased relative hepatic enhancement. A patient's dietary status, however, should not influence the CT protocol.

Carcinoid metastases to the liver: role of triple-phase helical CT

PURPOSE

To evaluate triple-phase helical computed tomography (CT) of carcinoid liver metastases.

MATERIALS AND METHODS

Triple-phase helical CT was performed in 31 patients with proved carcinoid liver metastases. Hepatic arterial-dominant phase (HAP) and portal venous-dominant phase (PVP) images were obtained 20 and 70 seconds after intravenous iopamidol injection. Four independent readers reviewed each phase for lesion number, conspicuity, and attenuation relative to liver. Three readers reviewed each phase to determine which phase best showed the lesions.

RESULTS

The lesions detected by readers 1-4 were as follows: noncontrast phase, 164, 177, 204, and 229 lesions; HAP, 178, 177, 214, and 238 lesions; and PVP, 180, 189, 215, and 250 lesions (P > .05). On HAP images, readers found that 80, 73, 96, and 102 lesions were hyperattenuating. Consensus indicated there were 206 focal lesions. Of these 206 lesions, 72, 72, and 62 lesions were best seen on the noncontrast phase, HAP, and PVP images, respectively. Six, 28, and six lesions were seen only on the noncontrast phase, HAP, and PVP images, respectively. Two patients had lesions seen only on the HAP images.

CONCLUSION

The HAP and, to a lesser extent, the noncontrast phase provide added value in evaluating carcinoid liver metastasis.

Contrast-enhanced CT of intrahepatic and hilar cholangiocarcinoma: delay time for optimal imaging

OBJECTIVE

The purpose of this study was to determine the optimal time for obtaining delayed images with contrast-enhanced CT in patients who have intrahepatic or hilar cholangiocarcinoma.

SUBJECTS AND METHODS

CT studies were performed in 25 consecutive patients with proven cholangiocarcinoma, including six patients who had undergone radiotherapy or chemotherapy. Dynamic images of the liver were obtained after 150 ml of IV contrast material was administered at 3 ml/sec. Delayed CT images were then obtained at 10, 20, and 30 min. Tumor-liver attenuation difference was determined quantitatively for each time period. Images were qualitatively evaluated by three observers for attenuation of the tumor (hypoattenuating, isoattenuating, or hyperattenuating) relative to the liver. Observer confidence for tumor detection was graded on a four-point scale. Dynamic and delayed images were compared for tumor conspicuity.

RESULTS

On dynamic images, 18 tumors (72%) were hypoattenuating, six (24%) were isoattenuating, and one was heterogeneous. On delayed images, 15 (60%) of these 25 tumors were isoattenuating and nine (36%) were hyperattenuating compared with the liver. Tumor-liver attenuation difference was greatest on dynamic studies (p < .01) and did not differ significantly among the three delay times (p > .20). All tumors seen on delayed images were also seen on dynamic images; however, in three patients (12%), the confidence level for presence of tumor was better on delayed than on dynamic images. Confidence levels for presence of tumor did not vary significantly among the three delay times. Attenuation values on dynamic and delayed images did not differ for the groups of patients who had or had not undergone prior radiotherapy or chemotherapy (p > .05).

CONCLUSION

In the evaluation of hilar or intrahepatic cholangiocarcinoma, delayed CT images are helpful for tumor characterization and may improve observer confidence for the presence of tumor. The optimal time for acquisition of delayed images is 10-20 min after contrast media injection.

Pancreatic malignancy: effect of dual-phase helical CT in tumor detection and vascular opacification

PURPOSE

To determine the relative value of hepatic arterial and portal venous phase helical computed tomographic (CT) scans for tumor detection and vascular opacification in patients with pancreatic malignancy.

MATERIALS AND METHODS

Ninety-five patients who had or were suspected of having pancreatic disease underwent dual-phase helical CT. Arterial phase scans were acquired 20-40 seconds after contrast material administration; venous phase scans, 70-100 seconds after administration. Three readers independently scored images in a blinded fashion for the presence of tumor, for lesion attenuation relative to normal pancreas, and for vascular opacification.

RESULTS

The final diagnosis was pancreatic malignancy (n = 60), acute or chronic pancreatitis (n = 22), and normal pancreas (n = 13). The readers identified possible or definite tumors on arterial phase studies in 47-50 patients and on venous phase studies in 48-53 patients (P > .10). There was no statistically significant difference in tumor attenuation between scans from the two phases (P > .05). Agreement between the readers for tumor detection was not affected by the scanning phase (P > .10). Opacification of arteries and of veins was greater on arterial phase scans and on venous phase scans, respectively (P < .001).

CONCLUSION

The acquisition of arterial phase scans in addition to venous phase scans does not result in improved detection of pancreatic malignancies.

Humanized anti-CD4 monoclonal antibody therapy of autoimmune and inflammatory disease

We have investigated the biological and therapeutic properties of a humanized anti-CD4 MoAb, hIgG1-CD4, in patients with refractory psoriasis and rheumatoid arthritis (RA). hIgG1-CD4 is a modulating, non-depleting MoAb, which induced a first-dose reaction in most patients treated. It provided brief symptomatic relief in both conditions, and psoriasis appeared easier to control with conventional agents after MoAb therapy. At the doses used, hIgG1-CD4 did not synergize therapeutically with the panlymphocyte MoAb CAMPATH-1H (C1H) in patients with RA treated sequentially with both agents. There were no serious adverse effects definitely attributable to therapy. Our results are compared with those of other CD4 MoAb studies, and factors influencing the outcome of therapy are discussed.

Early systole in the healthy kidney: variability of Doppler US waveform parameters

PURPOSE

To determine the sampling variability of intrarenal Doppler ultrasound (US) indexes of early systole in a screened population of healthy individuals.

MATERIALS AND METHODS

Doppler US measurements were obtained in the superior, middle, and inferior regions of 132 kidneys in 66 healthy, potential kidney donors. All individuals subsequently underwent angiography. Systematic measurement differences and random effects were estimated for sampling from a particular parenchymal region, from a kidney in a subject, from an individual in a population, and from a vascular territory.

RESULTS

Coefficients of variations ranged from 20% to 30%. Most (55%-66%) of the observed variation was attributable to random differences between repeated measurements in the same kidney. No systematic variations attributable to kidney region, vascular territory, right versus left kidney, or subject age were found for acceleration time, acceleration, or waveform shape. Some evidence of fixed variation between kidneys and between regions was found for peak systolic velocity, but the magnitude of this variation was small. Averages of repeated measurements may decrease the probability of exceeding the normal threshold for acceleration but not for acceleration time.

CONCLUSION

Measurements of Doppler parameters of the early systole have substantial intrinsic variability. Thus, caution is needed when interpreting small changes in these measurements within a kidney or between individuals.

Abdomen after a Puestow procedure: postoperative CT appearance, complications, and potential pitfalls

PURPOSE

To evaluate the postoperative computed tomographic (CT) appearance, complications, and potential pitfalls after a Puestow procedure (lateral side-to-side pancreaticojejunostomy).

MATERIALS AND METHODS

Forty CT examinations were performed after the Puestow procedure in 20 patients. Images were retrospectively reviewed by three radiologists.

RESULTS

The pancreaticojejunal anastomosis was identified at 30 examinations and was immediately anterior to the pancreatic body or tail. The anastomosis contained fluid or gas on 11 scans and oral contrast material on four scans. On 15 scans, the anastomosis appeared as collapsed bowel without gas, fluid, or oral contrast material. The Roux-en-Y loop was identified on 28 (70%) scans and contained fluid or gas on 16 scans and oral contrast material on six scans. The Roux-en-Y loop appeared as collapsed bowel on six scans. When the anastomosis or Roux-en-Y loop contained fluid and gas, the appearance mimicked that of a pancreatic or parapancreatic abscess. Peripancreatic stranding was present on 28 scans and was due to either ongoing pancreatitis or postoperative change. Complications included 15 transient fluid collections, three abscesses, four pseudocysts, one hematoma, and one small-bowel and Roux-en-Y obstruction.

CONCLUSION

Knowledge of the anatomy after a Puestow procedure is essential for accurate interpretation of CT scans.

Local recurrence of rectal cancer: evaluation with F-18 fluorodeoxyglucose PET imaging

BACKGROUND

Positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) is a useful technique for detection of malignancy. The purpose of this study was to determine if FDG-PET scanning using visual and quantitative analyses can identify patients with recurrent colorectal tumor following abdominoperineal resection.

METHODS

Eighteen patients were evaluated for possible local recurrence of rectal carcinoma following abdominoperineal resection. The clinical presentation included rising carcinoembryonic antigen levels (n = 5), increasing size of a presacral mass on computed tomography or magnetic resonance (n = 13), or local symptoms (n = 3). Axial PET images of the pelvis were obtained following an injection of 10 mCi of FDG prior to biopsy. Quantitative analysis was performed by calculation of a standardized uptake ratio (SUR), and the images were interpreted by two radiologists in consensus. FDG-PET findings were correlated with histological or cytological findings and with the clinical outcome.

RESULTS

Recurrent malignancy was confirmed in 13 patients by surgery (n = 8) or percutaneous biopsy (n = 5). Benign lesions were confirmed in five patients by surgery (n = 1), biopsy (n = 3), or clinical follow up (n = 1). Visual analysis of the FDG-PET data had a sensitivity of 92.3% (12/13) for recurrent disease (95% confidence limits; 63.9%, 99.8%) and a specificity of 80% (4/5; 95% confidence limits; 28.3%, 99.4%). SUR values were significantly higher in malignant lesions (range = 2.92-19.74, mean = 6.89) than in benign ones (range = 1.40-3.47, mean = 1.96; p = 0.002).

CONCLUSION

FDG-PET is an accurate technique for detection of locally recurrent colorectal carcinoma. Visual analysis is equivalent to quantitative analysis for detection of disease.

Zebra pattern: a diagnostically challenging hepatic parenchymal enhancement pattern at CT arterial portography

PURPOSE

To investigate the effect of arterial injection site and splenic volume on the hepatic zebra pattern seen at computed tomographic (CT) arterial portography.

MATERIALS AND METHODS

Images from CT arterial portographic examinations, performed via either the splenic artery (SA)(n = 47) or superior mesenteric artery (SMA)(n = 51) in 98 patients, were reviewed. The hepatic parenchymal enhancement pattern was assessed by three blinded reviewers. Splenic volume was determined.

RESULTS

Twenty-two of 98 (22%) CT arterial portographic studies showed a zebra pattern: 10 of 47 (21%) with injection via the SA and 12 of 51 (24%) with injection via the SMA. The mean percentage of hepatic parenchyma with nontumorous perfusion defects was 55% with the zebra pattern versus 12% without (P < .001). For SA injections, the mean splenic volume was lower in patients with the zebra patterns (321 vs 409 cm3, P = .09). For SMA injections, it was higher in patients with zebra patterns (372 vs 291 cm3, P = .10).

CONCLUSION

The zebra pattern can cause difficulties in interpreting images. It is due to alternating, well-defined regions of portal venous hyper- and hypoperfusion; it likely has a multifactorial cause and is likely due to technical parameters such as the injection site, the volume of the spleen, and the hemodynamic effects of the tumor.

Doppler US measurement of portal venous flow: variability in healthy fasting volunteers

PURPOSE

To describe the intrinsic sampling variability of measurements of portal venous flow in healthy volunteers and to estimate the variability attributable to the sonographer, the subject, and the measurement.

MATERIALS AND METHODS

In a randomized controlled fashion, nine sonographers measured portal venous flow in five subjects. Each sonographer measured portal venous flow in each volunteer during three separate sessions with three measurements per session. Analysis of variance was used to estimate the contribution of several factors to the observed variability.

RESULTS

Overall mean portal venous flow was 390 mL/min +/- 234 (range, 18-1,511 mL/min). The estimated variance components were 1.1 (3%), 2.5 (7%), 7.2 (21%), and 24.0 (69%) for the subject, the sonographer, the interaction between subject and sonographer, and the measurement or intrinsic variability. Similar results were obtained when the analysis of variance was fit by using the rank and median of the measurements.

CONCLUSION

Substantial variability exists in measurement of portal venous flow. Variability attributed to inherent differences in repeat measurements contributes more to overall variability than that attributed to either sonographers or subjects.

The diagnostic accuracy/efficacy of MRI in differentiating hepatic hemangiomas from metastatic colorectal/breast carcinoma: a multiple reader ROC analysis using a jackknife technique

PURPOSE

Our purpose was to determine the diagnostic accuracy efficacy of a simple MR technique in differentiating hepatic hemangiomas from colorectal or breast metastases using a multiple reader method.

METHOD

Thirty-seven cases with confirmed hepatic hemangiomas and 115 with confirmed hepatic metastases (colon primary, n = 86; breast primary, n = 29) evaluated with MRI at 1.5 T were retrospectively collected. A single lesion in a single slice from each patient was randomly selected; the images were masked and then were interpreted in random order by five separate readers blinded to the diagnosis using a five point diagnostic scale (from definite hemangioma to definite metastasis). Morphologic characteristics of lesion margin, signal intensity relative to other structures, and internal architecture (homogeneous versus heterogeneous) were also assessed independently of the five point diagnostic scale. Three of the readers had > 8 years of experience, while the other two had 1 and 3 years. The diagnostic scale results were subjected to receiver operating characteristic (ROC) analysis using a jackknife method. kappa-Statistics were applied to assess interreader agreement in the morphologic characteristics. A logistic regression model was used to determine which characteristics predicted pathology and reader diagnosis.

RESULTS

ROC analysis showed the average area under the curve over all readers was (0.91 (0.89-0.93 95% confidence interval) (p < 0.0001). An analysis of variance showed no significant difference between the areas under the curves of each reader (p = 0.6433). When the definite and probable categories for hemangioma and metastasis were combined, the sensitivity/specificity for the diagnosis of hemangioma ranged from 57 to 73%/91 to 97%. The positive/negative predictive value ranged from 72 to 84%/87 to 91%. For the morphologic assessment, there was significant agreement between the readers (p < 0.0001-0.0037). A sharp margin and lesion signal equal to or greater than CSF predicted the presence of a hemangioma (p = 0.0148 and p < 0.0001, respectively). A sharp margin, lesion signal equal to or greater than CSF, and a homogeneous internal architecture all predicted the reader diagnosis of definitely or probably hemangioma.

CONCLUSION

For multiple readers, T2-weighted SE MRI alone is a very specific method for distinguishing hemangiomas from metastatic colon or breast carcinoma. Morphologic characteristics of a sharp margin and a high signal predict the presence of a hemangioma. Last, reader experience does not appear to have a significant effect on the specificity.

Liver MR imaging: comparison of respiratory triggered fast spin echo with T2-weighted spin-echo and inversion recovery

BACKGROUND

The purpose of this study was to compare a fast spin-echo sequence combined with a respiratory triggering device (R. trig. FSE) with conventional T2-weighted spin-echo (CSE) and inversion recovery (STIR) sequences for the detection of focal hepatic lesions.

METHODS

We performed a prospective study of 33 consecutive patients with known or suspected hepatic tumors. All patients underwent R. trig. FSE, CSE, and STIR imaging at 1.5 T. Acquisition times were 10.7 min for the CSE sequence and ranged from 12 to 15 min for STIR and from 5 to 7 min for R. trig FSE. For each sequence, liver-spleen contrast-to-noise ratio (CNR) and liver-lesion CNR were determined quantitatively. Image artifact and sharpness were graded by using a four-point scale on each sequence by two independent readers. Both readers also independently identified hepatic lesions (up to a maximum of eight per patient). For patients with focal lesions, the total number of lesions detected (on each sequence) and the minimum size of detected lesions were also determined by each reader.

RESULTS

No significant difference was detected between R. trig. FSE and CSE or STIR in either liver-spleen CNR or liver-lesion CNR. R. trig. FSE images were equivalent to CSE and superior to STIR in sharpness (p < 0.01) and presence of artifact (p < 0.01). R. trig. FSE detected a higher number of lesions (reader 1: n = 92, reader 2: n = 86) than CSE (reader 1: n = 70, reader 2: n = 69) and a significantly higher number than STIR (reader 1: n = 71, reader 2: n = 76). Lesion structure was significantly better defined with R. trig. FSE than with STIR (p < 0.01) and CSE (p < 0.05).

CONCLUSIONS

Compared with CSE and STIR, R. trig. FSE produces hepatic images of comparable resolution and detects an increased number of focal hepatic lesions in a shorter period of time.

Hepatic artery: variability in measurement of resistive index and systolic acceleration time in healthy volunteers

PURPOSE

To determine the intrinsic sampling variability of measurements of hepatic artery resistive index and systolic acceleration time in healthy subjects and to estimate the components of variability attributable to the sonographer, individual measurement, and subject.

MATERIALS AND METHODS

In a randomized, controlled (blinded) fashion, nine sonographers measured hepatic artery resistive index and systolic acceleration time in five healthy subjects by using Doppler ultrasound (US). Analysis of variance was used to estimate the contribution of several factors to the observed variability in measurements.

RESULTS

The standard deviation for a single measurement was 0.08 for resistive index and 39 msec for systolic acceleration time. For resistive index, the estimated variance components were 0.0012 (18%), 0.0004 (6%), and 0.0050 (76%) for the subject, sonographer, and intrinsic variability, respectively. For systolic acceleration time, the estimated variance components were 59 msec (4%), 264 msec (17%), and 1,250 msec (79%) for the subject, sonographer, and intrinsic variability, respectively.

CONCLUSION

Because of substantial variability in hepatic arterial measures, caution is indicated when interpreting small changes in the measurement of these Doppler US indexes.

CT during arterial portography: comparison of injection into the splenic versus superior mesenteric artery

PURPOSE

To determine whether the diagnostic quality of computed tomography (CT) during arterial portography (CTAP) performed via the splenic artery (SA) is better than that performed via the superior mesenteric artery (SMA).

MATERIALS AND METHODS

The authors evaluated CTAP images obtained in 98 patients from 1991 to 1994; 47 examinations were performed via the SA and 51 were performed via the SMA. Images were reviewed, by consensus, by three radiologists blinded to catheter location. Hepatic enhancement was quantitatively assessed in 53 patients (31 in the SA group, 22 in the SMA group).

RESULTS

The numbers of low-attenuation non-tumor-related perfusion defects (19 in the SA group, 17 in the SMA group), high-attenuation non-tumor-related perfusion defects (six in the SA group, six in the SMA group), diffuse mottled perfusion abnormalities (six in the SA group, five in the SMA group), and portal venous flow defects (20 in the SA group, 20 in the SMA group) were similar in both groups (P > .05). Peak hepatic enhancement was similar in both groups (SMA group = 111 HU; SA group = 112 HU) (P > .05).

CONCLUSION

There is no difference in quality between CTAP performed via the SA versus CTAP performed via the SMA.

Renal resistive indexes: variability in Doppler US measurement in a healthy population

PURPOSE

To determine the variability in resistive index (RI) in normal kidneys, possible causes of variability, and consequences of reporting a single value.

MATERIALS AND METHODS

Doppler ultrasound RI measurements were obtained in the upper, middle, and lower regions of 118 kidneys in 58 healthy subjects (aged 24-70 years; 35 women, 23 men) who subsequently underwent angiography. The effects of sampling a particular parenchymal region, vascular territory, or kidney were assessed.

RESULTS

Kidney region, vascular territory, and right versus left kidney had no consistently significant effect (P < or = .05) on RI. Age had a statistically significant effect. RI readings were highly correlated with each other both within a subject and within a kidney. The probability that a single RI value would exceed 0.70 in a healthy 45-year-old subject was 6%; this decreased to 3% when three readings were averaged.

CONCLUSION

The variability of RI measurements in a kidney suggests that a number of RI readings should be averaged before a single representative value is reported.

Malignant melanoma metastatic to the gastrointestinal tract

Malignant melanoma, a common malignancy whose prevalence is increasing, represents 1-3% of cancers in the United States [1]. At autopsy, metastatic deposits to the gut are frequently found, but less than 9% of melanoma patients are diagnosed with gastrointestinal metastases while living [2]. Modern management includes aggressive surgical therapy to prolong survival and to palliate the disease [3]. Therefore, imaging of metastatic melanoma is clinically important to detect extent and determine whether the patient would benefit by surgery. Gastrointestinal metastases may manifest as mucosal or submucosal masses, serosal implants, or carcinomatosis [4]. They arise more commonly in the mesentery or distal small bowel than the proximal gastrointestinal tract or colon. The purpose of this essay is to illustrate the appearance of melanoma metastatic to the gastrointestinal tract on luminal contrast studies and on CT and to emphasize the importance of early investigation of gastrointestinal symptoms in a patient with a history of malignant melanoma.

Urinary bladder diverticula: sonographic diagnosis and interpretive pitfalls

Diverticula of the urinary bladder can occasionally appear as complex pelvic masses not obviously connected to the bladder. Such presentations can lead to diagnostic confusion and interpretative error. Sonographic findings and clinical histories were reviewed in 11 patients in whom bladder diverticula were initially mistaken for other types of pathologic pelvic processes. Sonographic techniques that were helpful in elucidating the true nature of the lesions included scanning from different perspectives with increasing increments of bladder distention, postvoid images, endovaginal views, and color Doppler interrogation. The diagnosis of bladder diverticula should be considered and actively pursued when sonologists are confronted with pelvic masses of ambiguous origin.

Doppler sonography in the evaluation of corporovenous competence after penile vein ligation surgery

Doppler ultrasonographic findings in patients after penile vein ligation surgery are described and compared to the results of cavernosometry and cavernosography. Peak systolic and end diastolic velocities were recorded for both cavernosal arteries at 5 min intervals after papaverine injection for a total of 30 min. Peak end diastolic flow rates were compared with cavernosometric and cavernosographic results at 0-10 min, 11-20 min, and 21-30 min. Cavernosography identified venous leakage in nine patients. The end diastolic velocities were greater than the 5 cm/s threshold level generally considered to be indicative of venous leakage in nine of the nine patients (100%) at 0-10 min, in eight of the nine (89%) at 11-20 min, and in nine of the nine (100%) at 21-30 min. Although peak end diastolic velocities at or near the 5 cm/s threshold could be found in patients both with and without recurrent venous leakage in the initial 10 min of the studies, only patients with recurrent venous leakage had diastolic velocities that exceeded the 5 cm/s level when measured 10 min or more after injection. Measurement of end diastolic velocities between 21 and 30 min after injection seemed to discriminate most effectively the patients with recurrent venous leakage from those without leakage in the postoperative population.

Use of time during body computed tomography scanning in a tertiary care teaching hospital: focus on patient throughput

RATIONALE AND OBJECTIVES

To control costs, it is increasingly important to make efficient use of imaging technology. We sought to determine and analyze the time required to complete each step of a body computed tomography (CT) scan, focusing on factors that influence patient throughput.

METHODS

Over 4 weeks, we prospectively monitored the time required for each step of a body CT scan (i.e., image time, check time, and clear time). Covariate data were collected by patient status: outpatient, inpatient, emergency department (ED), and intensive care unit (ICU); work shift; and radiologist training level (junior resident, senior resident, fellow, and attending). Technologists also predicted whether repeat images would be requested by the radiologist.

RESULTS

Three hundred eighty CT examinations were studied: 277 for outpatients, 90 for inpatients, 9 for ED patients, and 4 for ICU patients. The mean total examination time was 44.7 min (mean image time = 33.1 min, mean review time = 8.2 min, and mean clear time = 3.4 min), which did not differ significantly with patient status. A second opinion was sought from a consultant radiologist on the scans of 44 patients. Consultation was requested significantly more frequently (1) by junior residents than by senior residents or fellows and (2) for ED and ICU patients (22% and 50%, respectively) than in outpatients and inpatients (10% and 14%, respectively). Repeat images were obtained from 75 patients, and this was not significantly related to patient status, scan type, or radiologist training level. When the technologist predicted that no repeat images were needed, this prediction agreed with the radiologist in 86% of the cases. When the technologist predicted that repeat images were necessary, this prediction agreed with the radiologist in 56% of the cases.

CONCLUSION

Reviewing scans before the patient leaves the CT suite adds considerably to the total time required to complete a scan, particularly if junior residents review scans. If technologists obtain repeat images at their discretion, time would be saved.

Doppler sonography in the diagnosis of antepartum pyelonephritis: value of intrarenal resistive index measurements

This study aims to define the effects of pyelonephritis on intrarenal resistive indices and to determine the role of Doppler sonography in the diagnosis of pyelonephritis in pregnant patients. Twenty pregnant women with pyelonephritis underwent renal Doppler sonography with calculation of intrarenal resistive indices. The resistive index was calculated for the upper, lower, and interpolar areas of each kidney in the patients with pyelonephritis (40 kidneys) and was compared to the resistive indices for a control group of 153 normal asymptomatic pregnant women (306 kidneys). Doppler findings were correlated with the location (sidedness) of flank pain in the pyelonephritis group. The mean resistive index values of patients with pyelonephritis were 0.04 higher than in the controls, and this difference was statistically significant (P < 0.001). Four patients with pyelonephritis had a mean resistive index > or = 0.70, whereas the remaining 16 patients had resistive indices within the normal range of < or = 0.70. In patients with confirmed pyelonephritis and unilateral pain, the average resistive index in the kidney on the side of pain was 0.03 greater than that on the asymptomatic side (P = < 0.01). The mean renal resistive index is significantly greater in pregnant patients with pyelonephritis than in pregnant women without pyelonephritis. Even so, the magnitude of the differences in resistive index is too small and the overlap between the groups too large for this parameter to be of discriminating clinical value.