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D M Balfe

Publications and source records attributed to D M Balfe.

At least 55 records · Page 3Linked to original sources
PubMed1995

Pancreatic adenocarcinoma: CT versus MR imaging in the evaluation of resectability--report of the Radiology Diagnostic Oncology Group.

PURPOSE: To compare findings with computed tomography (CT) and magnetic resonance (MR) imaging in pancreatic adenocarcinoma and to determine optimal pulse sequences for MR imaging. MATERIALS AND METHODS: CT scans and MR images were compared of 189 adult patients with known or suspected adenocarcinoma of the pancreas. Levels of confidence were correlated with surgical and pathologic results. RESULTS: The accuracy of CT was 0.73 and of MR imaging was 0.70. The negative predictive value of CT was 0.28 and of MR imaging was 0.23. The positive predictive value of CT was 0.89 and of MR imaging was 0.88. Gradient-echo and T1-weighted spin-echo sequences ranked equally in evaluation of vascular invasion, T1-weighted spin-echo sequences were preferred for assessing lymphadenopathy, and T2-weighted spin-echo sequences were preferred for detecting hepatic metastases. CONCLUSIONS: Cross-sectional imaging modalities are useful in the identification of unresectable pancreatic carcinoma. CT is recommended for initial imaging assessment.

Adenocarcinoma↗
PubMed1995

Imaging of the common bile duct during laparoscopic cholecystectomy: sonography versus videofluoroscopic cholangiography.

OBJECTIVE: The purpose of this prospective study was to compare the accuracies of laparoscopic sonography and laparoscopic videofluoroscopic cholangiography in detecting common bile duct stones and in identifying ductal anomalies during laparoscopic cholecystectomy. SUBJECTS AND METHODS: Ninety-five patients who underwent laparoscopic videofluoroscopic cholecystectomy were prospectively studied with laparoscopic sonography and laparoscopic videofluoroscopic cholangiography. The number of successful studies, the time required to complete the study, and complications resulting from the study were recorded. The biliary system was evaluated for complete visualization of the common bile duct, visualization of the cystic duct, ductal anomalies, maximum diameter of the common bile duct, and common bile duct stones and/or debris. Also determined was whether laparoscopic sonographic findings altered operative management. RESULTS: Laparoscopic sonography was successfully performed in 93 of 95 patients, and laparoscopic videofluoroscopic cholangiography was successfully performed in 90 of 95 patients. The time required to complete laparoscopic sonography ranged from 3 to 18 min (mean +/- SD, 8 +/- 3 min), and that required to complete laparoscopic cholangiography ranged from 5 to 28 min (mean +/- SD, 14 +/- 6 min). Laparoscopic sonography visualized the complete common bile duct in 84 of 93 patients, and laparoscopic cholangiography did so in 86 of 90 patients. Laparoscopic sonography showed the cystic duct in 87 of 93 patients, and laparoscopic cholangiography did so in 80 of 90 patients. Laparoscopic sonography showed no ductal anomalies in any of the 93 patients. Laparoscopic cholangiography showed ductal variants in 13 of 90 patients; however, 11 of the variants were proximal to the sonographic scan plane. Laparoscopic sonography showed common bile duct stones in 12 of 93 patients, and laparoscopic cholangiography did so in five of 90 patients. Laparoscopic sonography altered operative management in two of 93 patients. CONCLUSION: Our results show that laparoscopic sonography is as accurate as laparoscopic videofluoroscopic cholangiography in visualizing the common bile duct and cystic duct and in detecting common bile duct stones. However, the data are too limited to determine whether laparoscopic sonography is as accurate as laparoscopic cholangiography in detecting ductal anomalies.

Adult↗
PubMed1995

MR imaging of the peritoneum and abdominal wall.

Knowledge of the peritoneal cavity and the peritoneal folds that subdivide it is useful in evaluating for the presence and spread of disease processes that affect the peritoneum. Many disease processes of the peritoneum and abdominal wall are well evaluated with MR imaging, especially as MR techniques improve. In some cases, information is obtained that is not available with other imaging techniques.

Abdominal Muscles↗
PubMed1994

Prediction of gallstone composition: synthesis of CT and radiographic features in vitro.

PURPOSE: To test a morphoradiographic algorithm designed to predict the composition of gallstones with use of computed tomography (CT) to define calcification patterns. MATERIALS AND METHODS: Two reviewers retrospectively evaluated the radiographic features of 120 separate in vitro specimens (59 radiopaque and 61 radiolucent), then classified the stones into several categories of composition with the algorithm. RESULTS: The most useful features for prediction of cholesterol composition were, in order of decreasing importance, stone shape, absence of dense calcification on plain radiographs, overall CT attenuation not higher than that of water, presence of a second generation of smaller stones, and a peripheral cover of calcification detected on CT scans of aging cholesterol stones. The greatest error occurred in distinction between stones with mixed composition (50%-79% cholesterol) and older stones with higher cholesterol content (80%-95% cholesterol). CONCLUSION: The range of qualitative CT appearances advances the possibility of predicting gallstone composition and potential outcome of nonsurgical treatment.

Bile Pigments↗
PubMed1994

Longitudinal image deblurring in spiral CT.

PURPOSE: To assess the feasibility of digital deconvolution techniques to improve longitudinal resolution of spiral computed tomography (CT) multiplanar reformations and evaluate how technical factors in deconvolution affect longitudinal resolution, noise, and edge ringing. MATERIALS AND METHODS: Longitudinal line spread function (LSF) of the system was estimated from longitudinal reformations of transaxial spiral CT images of a step test phantom. By using the estimated LSF, longitudinal reformations of the phantom and three clinical spiral CT studies were deconvolved by the methods of Wiener filtering and constrained iterative deconvolution. Edge ringing and image noise were quantified for Wiener filtering and constrained iterative deconvolution. RESULTS: Longitudinal reformations were substantially deblurred and resolution improved after deconvolution. Anatomic boundaries in clinical images were more clearly delineated after restoration. The methods of Wiener deconvolution and constrained iterative deconvolution improved the sharpness of the phantom step boundary at the expense of increased edge ringing and image noise. CONCLUSION: In longitudinal spiral CT reformations, blurring along the longitudinal axis can be reduced by Wiener filtering or constrained iterative deconvolution.

Technology, Radiologic↗
PubMed1994

CT appearance of intestinal ischemia and intramural hemorrhage.

CT scans have become an important diagnostic tool in the evaluation of abdominal disease. Patients with intestinal ischemia or intramural hemorrhage often are referred for radiologic evaluation because clinical and laboratory findings are not sufficiently specific for the physician to make a definitive diagnosis. The cross-sectional capability of CT scans permits direct visualization of mural, serosal, and mesenteric processes that usually can only be indirectly evaluated by conventional plain film or barium studies. Although the CT scan findings in intestinal ischemia and intramural hemorrhage often are relatively nonspecific, knowledge of these findings as well as an understanding of the pathophysiology and clinical features of these disorders will allow one to suggest a diagnosis, allowing further evaluation and treatment to proceed in a timely manner.

Gastrointestinal Hemorrhage↗
PubMed1993

Cervical esophageal web associated with a patch of heterotopic gastric mucosa.

Cervical esophageal webs are a relatively common finding on esophograms. We report a web resulting from the squamocolumnar junction produced by heterotopic gastric mucosa. The clinical significance of this lesion is discussed and the importance of differentiating it from Barrett's esophagus is stressed.

Barrett Esophagus↗
PubMed1993

Pharyngography after head and neck irradiation: differentiation of postirradiation edema from recurrent tumor.

OBJECTIVE: In patients previously irradiated for head and neck carcinomas, persistent soft-tissue thickening in the larynx and pharynx makes it difficult to distinguish between postirradiation edema and recurrent epidermoid carcinoma. The goal of this work was to characterize the standard double-contrast pharyngographic appearance after irradiation and to differentiate this appearance from that of recurrent or residual neoplasms. MATERIALS AND METHODS: The posttreatment pharynogograms in 43 patients treated with radiotherapy for malignant tumors of the head and neck were retrospectively reviewed. The pharynx had been included in the radiation field in each case. We characterized the posttherapy appearance and identified radiographic signs that could be used to distinguish normal postirradiation edema from recurrent tumor. RESULTS: Soft-tissue thickening of normal laryngeal and pharyngeal structures and laryngotracheal aspiration were common nonspecific findings on posttherapy pharyngograms, each occurring in 39 of 43 patients. Epiglottic enlargement and laryngotracheal aspiration did not correlate with the presence of residual or recurrent neoplasm. Asymmetric swelling was more common ipsilateral to the original neoplasm and did not necessarily indicate a malignant tumor. Mucosal irregularity, ulceration, and a demonstrable focal mass were the only significant predictors of recurrent or residual tumor; at least one of the three findings was present in 17 of 19 patients with neoplasm correctly identified by pharyngography. CONCLUSION: Double-contrast pharyngography is a useful means of diagnosing pharyngeal tumors in patients who have had radiation therapy. Radiographic signs of neoplasm (ulcer, mucosal irregularity, and a focal mass) can be used to distinguish recurrent tumor from nonmalignant changes after irradiation.

Aged↗
PubMed1992

Spiral CT: decreased spatial resolution in vivo due to broadening of section-sensitivity profile.

Comparable conventional and spiral computed tomographic (CT) scanning protocols for transaxial (n = 30) and multiplanar reformation (MPR) (n = 15) imaging were performed to image the adrenal gland and the upper pole of the right kidney in the same patient, without use of intravenously administered contrast media. The sharpness of soft-tissue-fat interfaces oriented in the transverse (xy) and longitudinal (z) directions was measured as the maximum and full width at half maximum (FWHM) of the edge attenuation profile first derivative. Edge sharpness was qualitatively assessed by three blinded reviewers, who used a four-point scale. In vivo transaxial CT studies showed that the conventional scans produced slightly sharper edges than the spiral scans (mean difference of spiral and conventional FWHM = 0.30 mm [P < .05] [in z direction] and 0.21 mm [P < .05] [in xy direction]). In vivo MPR studies showed that interfaces in the xy plane were significantly less sharp with spiral scanning, whereas interfaces in the z direction were equivalent for conventional and spiral scanning (mean difference of spiral and conventional FWHM = 0.03 mm [P > .05] [in z direction] and 1.19 mm [P < .05] [in xy direction]). Significant respiratory misregistration was present on seven of 15 (47%) conventional MPR scans and on no spiral MPR scans.

Adipose Tissue↗
PubMed1991

Fluoroscopically guided nasoenteric feeding tube placement: results of a 1-year study.

Nasoenteric tube feeding is a widely used alternative to parenteral intravenous nutritional support or gastrostomy tube placement. Unmonitored tube passage may result in complications and delays the beginning of tube feedings. The authors studied the results of 882 fluoroscopically guided feeding tube placements in 448 patients in 1 year to determine rates of success and complications, as well as the long-term outcome of this population of patients. Seven hundred sixty-four attempts (86.6%) were successful in positioning the tube distal to the third portion of the duodenum. Four major complications (three fatal arrhythmias and one tracheobronchial injury) were encountered. Only seven patients (2%) experienced aspiration events that were due to positioning of the tube in the distal duodenum. Seventy-seven percent of patients required either one or two tubes; the average "tube life" was 7.8 days. Most repositionings were required because of patient noncompliance or inappropriate administration of solid medications. Fluoroscopically guided nasoenteric tube passage is safe, easily performed, and highly successful, and has resulted in widespread clinical acceptance in our institution.

Aged↗
PubMed1991

Laparoscopic cholecystectomy: evaluation with sonography.

To determine the normal postoperative appearance of gallstones in the common duct at ultrasound (US) examination, the significance of fluid collections after surgery, and the usefulness of routine postoperative scanning, US of the right upper quadrant was performed in 106 consecutive patients 24 hours after laparoscopic cholecystectomy. The location, volume, and appearance of fluid collections were recorded. The maximum diameter of the common duct was measured in all patients and compared with preoperative measurements in 58 patients. Small fluid collections were identified in the gallbladder fossa in 56 patients (53.0%). Fluid collections did not correlate with fever or white blood cell count. In 15 of 58 patients, the diameter of the common duct had increased on the postoperative scan. This did not correlate with alkaline phosphatase or bilirubin levels. One hundred one patients (95.3%) were discharged the day after surgery. Routine US performed the day after surgery did not alter management; the authors conclude that it is unwarranted in their group of patients.

Adult↗
PubMed1991

Perfluoroctylbromide as a gastrointestinal contrast agent for MR imaging: use with and without glucagon.

The utility of perfluoroctylbromide (PFOB) as a gastrointestinal contrast agent for magnetic resonance (MR) imaging was evaluated with MR examinations performed in 30 subjects (16 healthy volunteers and 14 patients). Transaxial T1-, proton density-, and T2-weighted MR images were acquired in each subject before and after the administration of PFOB. The healthy volunteers each underwent two sets of post-PFOB MR examinations, one before and one after glucagon administration. The degree of bowel marking, clarity of bowel-wall visualization, ability to distinguish bowel from adjacent parenchymal organs, and severity of phase-encoding artifacts were independently analyzed by two reviewers. Oral administration of PFOB significantly (P less than .001) increased the percentage of bowel loops with low signal intensity. Subcutaneous administration of glucagon significantly (P less than .001) increased the clarity of bowel-wall visualization on post-PFOB MR studies. The severity of phase-encoding artifacts did not change substantially after administration of PFOB or glucagon.

Adult↗
PubMed1990

Lymphoma in the wall of the bile ducts: radiologic imaging.

Extranodal lymphoma is not uncommon; however, lymphomatous involvement of the wall of the bile duct is rare, with only a few case reports available. Three cases were imaged with computed tomography (CT) and direct cholangiography at our institution. In one, Hodgkin disease recurred in the duct wall, producing a radiographic pattern indistinguishable from sclerosing cholangitis. In another, central sclerosis on cholangiography was associated with a separate liver mass identified by CT. This presentation of non-Hodgkin lymphoma mimicked cholangiocarcinoma. The third patient had multifocal, diffuse histiocytic lymphoma arising in the gallbladder and cystic duct, as well as in the kidneys and pancreas. Although the condition is unusual, the diagnosis of lymphoma in the bile duct wall should be considered, particularly when the cholangiographic picture of diffuse central sclerosis is associated with little or no observable mass on CT.

Adenoma, Bile Duct↗