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G W Boland

Publications and source records attributed to G W Boland.

At least 37 records · Page 2Linked to original sources
PubMed1997

Adrenal masses: characterization with delayed contrast-enhanced CT.

PURPOSE: To evaluate the use of attenuation measurements from early delayed computed tomographic (CT) scans to differentiate benign from malignant lesions of the adrenal glands. MATERIALS AND METHODS: Forty-four patients (19 men, 25 women; age range, 21-88 years; mean age, 63 years) with 46 adrenal masses underwent dynamic contrast material-enhanced CT and early delayed CT (range, 12-18 minutes; mean delay, 14 minutes) with similar scanning parameters. Each patient also underwent non-contrast-enhanced CT within 3 months of the contrast-enhanced examination. Attenuation of adrenal masses on each type of scan was measured, and receiver operating characteristic analysis was performed. RESULTS: An attenuation threshold of 24 HU was selected; thus, all lesions with attenuation values of 24 HU or less were considered benign. When this threshold was applied to the results, the sensitivity of characterization of adrenal masses on early delayed scans was 96%, and the specificity was 96%. CONCLUSION: Adrenal masses detected with contrast-enhanced CT can be characterized as benign or malignant on early delayed scans of the adrenal glands.

Adrenal Gland Neoplasms↗
PubMed1997

Percutaneous gastrostomy with T-fastener gastropexy: results of 316 consecutive procedures.

PURPOSE: To assess the rates of technical success and complications associated with radiologic gastrostomy or gastrojejunostomy performed with T-fastener gastropexy. MATERIALS AND METHODS: In 316 consecutive patients, radiologic gastrostomy or gastrojejunostomy with T-fastener gastropexy was performed over a 10-year period. Results of the procedures were reviewed. Results of follow-up were available for all patients. RESULTS: Of 316 procedures, 314 were successful (technical success rate, 99.4%). Six (1.9%) major complications occurred; 50% occurred in patients with peritoneal involvement from ovarian carcinoma. Ten (3.2%) minor complications occurred. Four minor complications occurred in patients with ovarian cancer and ascites. The 30-day mortality rate was 3.8% (12 patients) with one procedure-related death (0.3%). CONCLUSION: A T-fastener gastropexy may have a protective role in prevention of leakage of gastric contents into the peritoneum in patients with ascites. Ascites need no longer be considered a contraindication for radiologic gastrostomy. A gastropexy enables routine use of larger gastrostomy tubes and ready replacement of a displaced tube even before the development of a mature tract.

Adult↗
PubMed1997

Anatomic variants of mesenteric veins: depiction with helical CT venography.

OBJECTIVE: The purpose of this study was to describe the variable anatomy of mesenteric veins on axial CT images and on volume-rendered CT venograms that use maximum intensity projection and shaded-surface display. SUBJECTS AND METHODS: Fifty-seven patients undergoing helical CT of the pancreas were included in the study. The mesenteric venous system was analyzed in 54 patients. Three patients were excluded because the helical CT data were unsatisfactory. RESULTS: On helical CT with maximum intensity projection and shaded-surface display, the superior mesenteric vein (SMV) was seen as a single trunk of variable length in 40 patients. In seven other patients, two mesenteric trunks merged separately with the splenic vein. In the remaining seven patients, the SMV was occluded by tumor. The inferior mesenteric vein drained into the splenic vein in 28 patients (56%), into the SMV in 14 patients (26%), and into the splenomesenteric angle in nine patients (18%). CONCLUSION: Both axial and volume-rendered CT venograms accurately reveal the variable mesenteric venous anatomy. CT venograms may replace conventional angiography in presurgical planning.

Female↗
PubMed1997

Arterial versus portal venous helical CT for revealing pancreatic adenocarcinoma: conspicuity of tumor and critical vascular anatomy.

OBJECTIVE: The purpose of this study was to determine the conspicuity of pancreatic adenocarcinoma and surrounding critical pancreatic vascular structures on helical CT scans obtained during the arterial and portal venous phases of enhancement. SUBJECTS AND METHODS: Forty patients with pancreatic adenocarcinomas under-went dual-phase helical CT (3-mm collimation; l-mm overlapping reconstructions; 160 ml contrast medium injected at 4 ml/sec; scan delay: 18 sec for arterial phase, 60 sec for portal venous phase). Tissue enhancement and differences in tumor-to-pancreas contrast were compared. Quantitative evaluation was also done for the aorta, the superior mesenteric artery and vein, and the splenic and portal veins. RESULTS: Tumor conspicuity was significantly greater in the portal venous phase, when the tumor-to-pancreas contrast difference was 54 +/- 31 H, than in the arterial phase, when the difference was 31 +/- 29 H. Enhancement values of critical pancreatic venous structures were significantly greater in the portal venous phase than in the arterial phase. CONCLUSION: Arterial-phase helical CT in patients with pancreatic adenocarcinoma is of limited benefit: lesion conspicuity is suboptimal and depiction of venous anatomy is inferior to the depiction possible with venous-phase helical CT.

Adenocarcinoma↗
PubMed1996

Imaging and interventional radiology in laparoscopic injuries to the gallbladder and biliary system.

Laparoscopic cholecystectomy has been prevalent in the United States since the late 1980s. Because of its increased use and potential for complications that can often be treated with interventional means, radiologists have become involved in treating patients with postlaparoscopic injury. This review details the imaging and interventional procedures involved in the care of patients with gallbladder and biliary problems due to laparoscopic cholecystectomy.

Bile Duct Diseases↗
PubMed1996

Articular muscle of the knee: a muscle seldom recognized on MR imaging.

OBJECTIVE: We studied the MR imaging characteristics of the articular muscle of the knee, an important but seldom recognized structure of the distal thigh and knee. SUBJECTS AND METHODS: We used a 1.5-T system to prospectively evaluate the articular muscle of the knee in five healthy volunteers (10 knees); then we retrospectively studied the knee examinations of 24 patients (30 knees). One reader made duplicate readings to prospectively assess the sagittal proton density-weighted and axial T1-weighted images of the healthy volunteers. Three independent readers retrospectively evaluated the sagittal proton density-weighted images of the 24 patients. RESULTS: The articular muscle of the knee was identified in 100% of prospective studies (10/10) and in 83% of retrospective studies (25/30). For the prospective study group, measurements (mean +/- SEM) were as follows: number of bundles, 2.4 +/- 0.68 (range, 1-4); length of uppermost bundle, 47.2 +/- 4.06 mm; width of origin, 8.6 +/- 0.79 mm; angle of origin, 11.4 degree +/- 1.29 degree; and cross-sectional bundle width, 19.8 +/- 2.05 mm2. CONCLUSION: The articular muscle of the knee can usually be identified by MR imaging as an independent entity, separate from the great (vastus) muscle group.

Adolescent↗
PubMed1995

Clostridium difficile colitis: correlation of CT findings with severity of clinical disease.

Clinical records and abdominal CT scans from 64 patients with documented Clostridium difficile disease were reviewed to determine if any correlation existed between CT findings of colitis and severity of clinical disease. Clostridium difficile disease was documented with stool toxin titre levels and CT scans were performed within 3 days of stool sample. Clinical disease severity was estimated by tabulating the degree of fever, WBC count, frequency and duration of diarrhoea. Thirty-nine of 64 patients showed CT evidence of colitis of which 28/39 showed evidence of focal colitis and 11/39 had pancolitis. CT findings suggesting colitis included colonic wall thickening (39 patients), nodular mucosal thickening (11 patients), the 'accordion pattern' (3 patients), pericolonic oedema (27 patients) and ascites (10 patients). Twenty-five of 64 patients showed no CT evidence of colitis. The clinical severity of disease did not statistically differ (P < 0.05) between patients with CT evidence of colitis and those without colitis. The only CT finding that correlated with clinical severity of disease was nodular mucosal thickening which was found with significantly (P < 0.05) more frequency in patients with a WBC count > 11,000 mm3. CT changes with Cl. difficile disease correlate poorly with the clinical severity. This and negative findings do not exclude the disease.

Adult↗
PubMed1995

Indeterminate adrenal mass in patients with cancer: evaluation at PET with 2-[F-18]-fluoro-2-deoxy-D-glucose.

PURPOSE: To evaluate the ability of positron emission tomography (PET) to characterize adrenal masses in patients with cancer. MATERIALS AND METHODS: Twenty-four adrenal masses (size range, 1.5-10.0 cm [mean, 2.8 cm]) in 20 patients (13 men and seven women) with cancer (lung [n = 10], colon [n = 3], lymphoma [n = 3], miscellaneous [n = 4]) were evaluated. PET was performed in fasting patients 45 minutes after infusion of 5-10 mCi (185-370 MBq) of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG). PET images were correlated with findings at computed tomography (CT), surgery, and/or percutaneous biopsy. RESULTS: Fourteen adrenal masses were proved malignant at surgery (n = 4), biopsy (n = 7), or follow-up (n = 3). Ten lesions were proved benign at biopsy (n = 4) or follow-up CT (n = 6). PET helped correct differentiation of benign from malignant adrenal lesions in all patients. A statistically significant difference (P < .001) was seen between mean tumor-to-background ratios for malignant (mean, 7.4; range, 2.9-16.6; median, 6.9) versus benign (mean, 0.8; range, 0.2-1.2; median, 0.6) adrenal lesions. CONCLUSION: PET helped correct differentiation of benign from malignant adrenal lesions.

Adrenal Gland Diseases↗
PubMed1995

Percutaneous ethanol injection for the treatment of hepatic tumors: indications, mechanism of action, technique, and efficacy.

Percutaneous injection of ethanol for treatment of hepatic tumors was first described by Sugiura et al. [1] in 1983. To date, reported experience with the procedure has focused mainly on therapy of hepatocellular carcinoma (HCC) [2-15], with little information available regarding its use in treating metastatic liver lesions [16]. Interest in this technique has grown recently as a possible means of treating patients with metastatic liver disease. The purpose of this perspective is to review the indications, mechanism of action, technique, complications, and efficacy of percutaneous ethanol injection for liver tumor treatment.

Carcinoma, Hepatocellular↗
PubMed1995

Characterization of adrenal masses (< 5 cm) by use of chemical shift MR imaging: observer performance versus quantitative measures.

OBJECTIVE: The purposes of this study were to evaluate the ability of chemical shift MR imaging to differentiate 1- to 5-cm adrenal adenomas from metastases and to compare subjective interpretation with several different quantitative measures. SUBJECTS AND METHODS: Forty-three patients with 46 proved adrenal lesions (28 adenomas and 18 metastases) had MR imaging with a gradient-echo breath-hold technique and echo time varied to obtain in-phase and out-of-phase images. Qualitative analysis of the MR images was done by three experienced observers, who reported their confidence in diagnosing the benignity versus the malignancy of the adrenal masses on the basis of signal loss on out-of-phase images. Quantitative analysis was performed by calculating the difference in signal intensity between in-phase and out-of-phase images by use of regions of interest (signal intensity index) and by use of adrenal-liver, adrenal-spleen, and adrenal-muscle signal intensity ratios. Results between quantitative and qualitative measures were compared by use of receiver operating characteristic (ROC) analysis. RESULTS: The mean signal intensity was significantly different between adenomas and metastases on out-of-phase images (64 versus 98) (p < .0005) but not in-phase images (130 versus 122) (p = .47). The adrenal-spleen ratio discriminated between adenomas and metastases better than did the adrenal-liver ratio, the adrenal-muscle ratio, or the signal intensity index. No significant difference in interpretation among the three observers was evident (areas under the ROC curves, 0.93, 0.95, and 0.96). The performance of the observers was comparable to the results obtained with the adrenal-spleen ratio measurement (area under the ROC curve, 0.97). CONCLUSION: Experienced observers were able to differentiate adrenal adenomas from metastases just as well as quantitative measures. The adrenal-spleen ratio is the best quantitative means of distinguishing benign from malignant adrenal masses. Chemical shift MR imaging is a good but imperfect discriminator of adrenal adenomas.

Adenoma↗
PubMed1995

Percutaneous drainage of subphrenic fluid collections that occur after splenectomy: efficacy and safety of transpleural versus extrapleural approach.

OBJECTIVE: The purpose of this study was to compare the safety and efficacy of transpleural and extrapleural approaches for draining left subphrenic abscesses in patients who have had splenectomy. MATERIALS AND METHODS: Twenty-five patients who had percutaneous catheter drainage (28 drainages) of postsplenectomy fluid collections were studied. Twenty drainages were transpleural and eight were extrapleural. In eight of the 20 transpleural drainages, it was elected to place the catheter transpleurally. In the remaining 12 patients, catheter drainage was judged to be transpleural on review, despite efforts to use an extrapleural approach. RESULTS: Sixteen of 18 patients who had transpleural percutaneous drainage and six of seven patients who had true extrapleural (subcostal) percutaneous drainage were cured by catheter drainage requiring no further intervention. The mean number of days of drainage was not significantly different (p > .05) for the group drained transpleurally (mean, 18 days; range, 1-90 days) versus the group drained extrapleurally (mean, 20 days; range, 6-43 days). Complications (pneumothorax) requiring treatment were seen in two patients in whom a transpleural approach was used and in none of the patients in whom an extrapleural approach was used. Complications that did not require treatment were seen in four further patients drained transpleurally. These were inadvertent placement of catheter into pleural space (two patients) and pneumothorax not requiring treatment (two patients). No patient had an empyema. CONCLUSION: Transpleural drainage of left subphrenic collections occurring after splenectomy is associated with a slightly increased complication rate but has a success rate similar to that of extrapleural drainage.

Adult↗
PubMed1995

An imaging algorithm for the differential diagnosis of adrenal adenomas and metastases.

OBJECTIVE: The purpose of this study was to develop an algorithm using CT and chemical-shift MR imaging for the characterization of adrenal masses in patients with a primary cancer and no other evidence of metastatic disease. SUBJECTS AND METHODS: Thirty-three patients with 37 adrenal masses (19 metastases, 18 adenomas), all of whom had a known primary cancer, were studied with noncontrast CT and chemical-shift MR imaging (1.5 T). Lesion size and density in Hounsfield units (H) were determined by CT. Adrenal signal intensity normalized to that of spleen was used to calculate adrenal-spleen ratio (ASR), defined as the percentage of signal remaining in the opposed-phase image relative to the in-phase image. Lesions less than or equal to 0 H were classified as benign, lesions greater than 20 H were regarded as malignant, and lesions between 0 and 20 H were regarded as indeterminate. Diagnoses were confirmed by biopsy (for 19 lesions) or by follow-up imaging (for 18 lesions). An imaging algorithm was derived by determining the relative value of CT and MR imaging for diagnosing the lesions. The reimbursement rates for CT-guided biopsy and MR imaging of the abdomen were obtained from Medicare. RESULTS: All 13 lesions of 0 or less H were correctly classified as benign by CT. ASR was less than 70 in 10 of these 13. In another 13 lesions, H was greater than 20; all were malignant and all had an ASR greater than 80. Of 11 CT-indeterminate lesions, four of five adenomas had an ASR less than 70, and four of six metastases had an ASR greater than 80. Two malignant lesions had ASRs between 70 and 80 and were diagnosed by biopsy findings. One CT-indeterminate adenoma had an ASR of 84 and was diagnosed by biopsy findings. The reimbursement rate by Medicare is similar for CT-guided biopsy with pathologic interpretation and for MR imaging of the abdomen. CONCLUSION: An algorithm was developed for diagnosis of adrenal lesions that uses the density reading on noncontrast CT as the first step, with chemical-shift MR imaging for CT-indeterminate lesions. In this algorithm, lesions of 0 H or less may be regarded as benign and further work-up is not required. Lesions with a density greater than 20 H are likely malignant and should be biopsied when the result will influence management. For CT-indeterminate lesions, we recommend chemical-shift MR imaging. An ASR threshold of 70 indicates a benign lesion, and no further workup is required in these patients. Lesions with an ASR greater than 70 should have a biopsy performed, depending on the clinical situation. The above algorithm is cost-effective and reduces the number of biopsies required without reducing the sensitivity of detecting malignant lesions.

Adrenal Cortex↗
PubMed1995

Magnetic resonance imaging of the adrenal gland.

The authors review their experience with magnetic resonance imaging (MRI) of the adrenal gland and discuss the appearance of adrenal diseases where MRI is clinically useful. A basic description of some of the newer pulse sequences is provided. Fat-suppressed MRI is advantageous because of reduction of cardiac and respiratory motion induced artifacts, accentuation of small differences in tissue contrast, and elimination of chemical shift artifacts. These advantages far outweigh the disadvantages of inhomogeneity of fat suppression and the fewer slices obtained per acquisition. Chemical shift imaging is used to differentiate benign from malignant adrenal diseases based on a gradient echo phase cycling technique. Detailed descriptions of MRI findings in adrenal pheochromocytomas, hemorrhage, cysts, adenomas, myelolipomas, and metastases are provided. Most pheochromocytomas appear markedly hyperintense to the liver on T2-weighted images. However, this appearance is not specific as adrenal metastases and adrenal adenomas may occasionally produce a similar appearance. In addition, pheochromocytomas may occasionally be isointense or hypointense to the liver on T2-weighted images. Differentiation of adrenal metastases from adrenal adenomas with MRI is problematic using signal intensity ratios (33% overlap) or T2 calculations. The future of discriminating between adrenal metastases and adenomas may rest with chemical shift MRI, which uses in- and out-of-phase gradient echo pulse sequences for differentiation. This approach relies on the fact that adrenal adenomas contain fat, while adrenal metastases do not. The reported accuracy of chemical shift imaging in differentiating between adrenal adenomas and adrenal metastases ranges from 96 to 100%. An algorithmic approach to differentiating benign from malignant adrenal diseases is presented that relies on an initial noncontrast CT with CT attenuation values obtained from the adrenal mass. If CT attenuation values are less than zero, the mass is characterized as benign. If the mass remains indeterminate after CT, chemical shift MR is performed. If the mass remains indeterminate after MR, biopsy is required.

Adenoma↗