PubMed Health⌕ Search

Biomedical subjects

P C Freeny

Publications and source records attributed to P C Freeny.

At least 55 records · Page 3Linked to original sources
PubMed1993

Incremental dynamic bolus computed tomography of acute pancreatitis.

Acute pancreatitis represents a wide spectrum of inflammatory disease involving the pancreas, peripancreatic tissues, adjacent solid organs, gastrointestinal and biliary tract, and vascular system. The extent and severity of the inflammatory process determines the prognosis of the patient and the need for specific surgical, endoscopic, and radiologically-guided intervention. Computed tomography is the single best imaging test for evaluating patients with acute pancreatitis. It can accurately stage the inflammatory process and can identify associated complications that require careful observation or immediate intervention. It also is essential for guiding percutaneous catheter placement for treatment of infected and noninfected fluid collections.

Acute Disease↗
PubMed1993

Diagnosis and staging of pancreatic adenocarcinoma with dynamic computed tomography.

We assessed the accuracy of dynamic contrast-enhanced computed tomography (CT) in the diagnosis and staging of 213 patients with pancreatic carcinoma and compared it with the accuracy of angiography and surgery. A correct CT diagnosis of pancreatic carcinoma was made in 207 of 213 (97%) patients. Tumors were located in the pancreatic head in 64%, the body in 22%, and the tail in 10%, and enlarged the pancreas diffusely in 4%. CT staged 25 (12%) patients as having potentially resectable tumors and 188 (88%) as having unresectable tumors on the basis of local extension (72%), contiguous organ invasion (43%), vascular invasion (82%), and distant metastases (50%). Compared with angiography in 60 patients, CT detected vascular invasion missed on angiography in 20%, and angiography detected invasion missed by CT in 5%. In these latter cases, other CT criteria of unresectability were present, and angiography provided no significant staging information. Compared with surgery in 71 patients, CT accurately predicted unresectable tumors in 100% of patients and resectable tumors in 72% of patients. Eleven of the patients with CT-resectable tumors underwent resection. Median survival was 22.7 months, with four patients alive at a median of 15.5 months postoperatively. Palliative resections were performed in six patients, and median survival was 14.4 months.

Adenocarcinoma↗
PubMed1993

Venous anatomy of the pancreatic head: normal CT appearance in cadavers and patients.

OBJECTIVE: This study was conducted to define the normal CT appearance of the four pancreaticoduodenal veins (anterior and posterior superior, and anterior and posterior inferior) in the head of the pancreas in injected cadaveric specimens and to assess the frequency with which these normal vessels are seen on dynamic contrast-enhanced CT scans. MATERIALS AND METHODS: The appearance of the four pancreaticoduodenal veins was studied on CT scans of four cadavers in which the portal veins were injected in situ with radiopaque solutions. A computer-generated three-dimensional model of the pancreatic head and its venous drainage was then produced from one cadaveric examination to show the venous anatomy. After definition of the venous anatomy in the cadaveric specimen, the anterior superior pancreaticoduodenal vein, posterior superior pancreaticoduodenal vein, and gastrocolic trunk were analyzed retrospectively on dynamic bolus contrast-enhanced abdominal CT scans of 100 consecutive patients who had no evidence of pancreatic disease. RESULTS: The anterior and posterior superior pancreaticoduodenal veins were seen on 98% and 88% of scans, respectively. The veins had mean diameters of 2.1 mm. The gastrocolic trunk was seen on 89% of scans and had a mean diameter of 4.7 mm. The inferior pancreaticoduodenal veins are small and were not identified definitively. CONCLUSION: The anterior and posterior superior pancreaticoduodenal veins and gastrocolic trunk are routinely visualized on CT scans of patients without pancreatic disease. Consequently, assessment of the veins may be useful in staging pancreatic carcinoma.

Cadaver↗
PubMed1993

CT of hypervascular hepatic tumors: are unenhanced scans necessary for diagnosis?

OBJECTIVE: In most institutions, a combination of unenhanced and contrast-enhanced CT is used to screen patients for suspected hypervascular hepatic neoplasms. Elimination of the unenhanced examination could save time and expense and reduce the patient's exposure to radiation. We compared unenhanced and incremental bolus dynamic contrast-enhanced CT for detection of hypervascular hepatic neoplasms and evaluated the need for preliminary unenhanced hepatic CT. SUBJECTS AND METHODS: We prospectively examined 101 consecutive patients with hypervascular primary hepatic malignant tumors or suspected hypervascular metastases. Primary hepatic neoplasms included hepatocellular carcinoma (seven), sarcoma (two), and hemangioendothelioma (one); extrahepatic primary tumors included breast (37) and renal cell (24) carcinoma, melanoma (15), carcinoid (nine), and endocrine and other tumors (six). All patients had both unenhanced and bolus dynamic contrast-enhanced CT with 5-mm collimated sections at 8-mm intervals. For contrast-enhanced CT, 150-180 ml of IV contrast material, a mechanical power injector, and a scanning protocol that allowed completion of liver imaging within 2 min were used. Both unenhanced and contrast-enhanced CT scans were compared for detection and conspicuousness of hepatic lesions. RESULTS: Hepatic lesions were found in 34 patients. In 21 patients, all hepatic lesions seen on unenhanced scans also were apparent on contrast-enhanced scans. However, in 12 (57%) of 21 patients, lesions were more conspicuous and better defined on contrast-enhanced scans. The absolute number of lesions detected with each method of scanning differed in 12 patients. In four patients, the contrast-enhanced scan showed more lesions; in five patients, the unenhanced scan showed more lesions; and in three patients, administration of contrast material obscured some lesions shown on unenhanced scans and made others more conspicuous. If only a contrast-enhanced CT scan had been obtained, the presence of malignant hepatic neoplasm would have been missed in only one case (a patient with a single 2.8-cm metastasis from renal cell carcinoma). CONCLUSION: Bolus dynamic contrast-enhanced CT alone correctly showed the presence or absence of primary or metastatic hypervascular hepatic tumors in 100 of 101 cases. If the goal of CT examination is detection of hypervascular hepatic lesions, use of contrast-enhanced CT alone may be adequate and the addition of unenhanced scans is not cost-effective.

Adult↗
PubMed1993

MR imaging with i.v. superparamagnetic iron oxide: efficacy in the detection of focal hepatic lesions.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of superparmagnetic iron oxide (SPIO) in the detection of focal hepatic lesions on MR images. SUBJECTS AND METHODS: The study included 21 patients with 115 focal hepatic lesions and eight patients without focal hepatic lesions. T1- and T2-weighted MR images were obtained at 1.5 T before and 60 min after the end of injection of an SPIO agent. Contrast-enhanced CT scans were obtained in all patients within 10 days after MR imaging. The effect of SPIO on the signal intensity of the liver and spleen was assessed by using quantitative analysis of the region of interest. Efficacy was evaluated by using multiple criteria and unenhanced and SPIO-enhanced images. Evaluations included subjective assessment of image quality, counting the number of lesions detected, and statistical analysis of quantitative changes in the signal intensity of lesions and of normal liver. RESULTS: By all criteria, SPIO-enhanced T2-weighted MR images were superior to unenhanced T2-weighted images and to contrast-enhanced CT scans. Conversely, by all criteria, SPIO-enhanced T1-weighted MR images were worse than unenhanced T1-weighted images and contrast-enhanced CT scans. The mean lesion-to-liver contrast on T2-weighted images was 317% on unenhanced images and 1745% on SPIO-enhanced images. For T1-weighted, the mean contrast was 26% on unenhanced images and 18% on SPIO-enhanced images. CONCLUSION: SPIO is an efficacious contrast agent for the detection of focal hepatic lesions when T2-weighted MR images are used.

Contrast Media↗
PubMed1992

Percutaneous management of pancreatic fluid collections.

Percutaneous catheter drainage of both infected and non-infected pancreatic fluid collections is a safe, efficacious procedure. The results of this procedure depend upon proper selection of patients based upon their clinical status as well as the morphological findings depicted by computed tomography and endoscopic retrograde cholangiopancreatography, careful preprocedural planning and execution of the drainage procedure, good catheter care with follow-up imaging and contrast studies, and attention to the criteria of catheter removal. An average success rate of 80% should be expected with a complication rate of about 15%.

Catheterization, Peripheral↗
PubMed1992

Hepatocellular carcinoma: reduced frequency of typical findings with dynamic contrast-enhanced CT in a non-Asian population.

Four computed tomographic (CT) findings have been described as typical or diagnostic of hepatocellular carcinoma: Primary morphologic findings include tumor encapsulation and fatty metamorphosis and secondary findings include venous invasion and arterioportal shunting. However, virtually all of the articles reporting these findings with significant frequency have been from Japan and thus represent an almost purely Asian population. The authors analyzed a series of 93 patients with hepatocellular carcinoma, only eight of whom were Asian. With the exception of venous invasion (48%), the analysis showed that while the four CT features may be typical of hepatocellular carcinoma, three features occurred with low frequency in a non-Asian population: tumor encapsulation, 12%; fatty metamorphosis, 0%; and arterioportal shunting, 4%. In addition, a review of the literature showed that all of the findings have occurred in other hepatic neoplasms, including benign and metastatic tumors.

Carcinoma, Hepatocellular↗
PubMed1992

Pancreaticoenteric fistula: no longer a surgical disease?

We report our experience with eight patients with severe persistent pancreatitis associated with peripancreatic fluid collections requiring placement of drainage catheters who subsequently developed pancreatic fistula. The fistulas were diagnosed by endoscopic retrograde cholangiopancreatography, contrast tube study, or Hypaque enema at a mean of 13 weeks after diagnosis of pancreatitis and drain placement. These fistulas involved the duodenum in five patients and colon in three patients. Six patients had fistula resolution with medical therapy (after removal of percutaneous drainage catheters in three and with drain removal in conjunction with transpapillary stenting of a disrupted pancreatic duct in another three). We conclude that in patients with ongoing pancreatitis, pancreaticoenteric fistulas are probably caused by erosion of percutaneous drainage catheters. Such fistulas resolved with conservative treatment in six of eight patients.

Catheters, Indwelling↗
PubMed1992

Radiology of the pancreas.

The techniques and applications of pancreatic imaging and interventional pancreatic radiology continued to expand in 1991. The most notable progress was the use of MR imaging for evaluation of the pancreas, particularly the investigation of contrast agents to produce enhancement of the pancreatic parenchyma. These agents offer considerable promise for the future of pancreatic MR imaging. The use of CT for detection and evaluation of complications of pancreatitis continued to grow and new investigations appeared that attempted to define the role of surgery vis-à-vis percutaneous and endoscopic interventional techniques. Finally, further understanding of cystic pancreatic neoplasms developed as the result of new investigations.

Diagnostic Imaging↗
PubMed1991

Invasive treatment of pancreatic fluid collections with surgical and nonsurgical methods.

Pancreatic fluid collections (PFC) can be drained surgically or nonsurgically with endoscopic or radiologic techniques. To define subgroups of patients with PFC who would benefit from the new modalities, we reviewed a period (1977 to 1990) during which both surgical and nonsurgical invasive techniques were available. Patients with phlegmon or necrosis at initial diagnosis were excluded. Sixty-five patients (35 male, 30 female) underwent 1 or more drainage procedures. A mean postprocedure follow-up of 10.2 months was available for 59 patients. Initial management was nonsurgical in 80% of patients. Procedures in patients with follow-up comprised invasive nonsurgical drainage (n = 25), invasive nonsurgical drainage plus surgery (n = 22), and surgery only (n = 12). Results for each group, respectively, were: morbidity, 20%, 20%, and 24%; mortality, 8%, 5%, and 0%; and successful drainage, 92%, 82%, and 83%. The choice of management appeared to be based on etiology and radiologic characteristics. Patients with nonalcohol- and nonbiliary-associated pancreatitis without a radiographically defined wall were more common in the invasive nonsurgical group and were successfully treated without surgery. Nonsurgical invasive techniques are efficacious in the treatment of PFC in this subgroup of patients.

Exudates and Transudates↗
PubMed1991

Root of the superior mesenteric artery in pancreatitis and pancreatic carcinoma: evaluation with CT.

To determine if changes involving the root of the superior mesenteric artery are specific for neoplasm, the authors retrospectively reviewed 173 computed tomographic (CT) examinations of patients with proved pancreatitis (103 examinations) and pancreatic ductal adenocarcinoma (70 examinations). Streaky infiltration of the fat surrounding the root was seen in 27 of 56 examinations of acute pancreatitis, in four of 24 examinations of chronic pancreatitis, in 12 of 23 examinations of pancreatitis complicated by abscess, and in 25 of 70 examinations of pancreatic carcinoma. Periarterial lymph nodes were visible in 14 with acute pancreatitis, in three with chronic pancreatitis, in six with pancreatic abscess, and in 11 with pancreatic carcinoma. A focal mass extended to within 1 cm of the root in 10 with acute pancreatitis, in two with chronic pancreatitis, in four with pancreatic abscess, and in 24 with pancreatic carcinoma; the mass obliterated the periarterial fat in seven with acute pancreatitis, in one with pancreatic abscess, and in 18 with pancreatic carcinoma. Circumferential encasement occurred in one with chronic pancreatitis, in four with pancreatic abscess, in 14 with pancreatic carcinoma, and in none with acute pancreatitis; nearly all cases of encasement revealed loss of periarterial fat. Thus, these indicators are not specific for neoplasm.

Abscess↗
PubMed1991

Angio-CT: diagnosis and detection of complications of acute pancreatitis.

The ability of high-resolution, current-generation fast (sub-2 sec) CT scanners to display the precise cross-sectional anatomy of the pancreas and surrounding organs and structures had made it the most efficacious imaging modality for evaluation of patients with known or suspected acute pancreatitis. The use of angio-CT (automatic table incrementation, dynamic scanning mode, simultaneous intravenous infusion of a large bolus of contrast) has further extended its use for detection of parenchymal necrosis and vascular involvement. CT now plays a central role in diagnosis, prognostication (staging of severity of disease), detection of complications, and guidance for percutaneous techniques.

Acute Disease↗
PubMed1991

Radiology of the pancreas.

This paper summarizes the major publications regarding imaging and intervention in pancreatic diseases from December 1989 through November 1990. This year, many of the most notable papers were published in the medical and surgical journals, reflecting that radiologic evaluation and intervention in patients with pancreatitis and pancreatic neoplasms are becoming standards of practice in many institutions.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1991

Endoscopic transpapillary therapy for disrupted pancreatic duct and peripancreatic fluid collections.

Eighteen patients with active pancreatic ductal disruptions, including 14 with definable fluid collections, were treated with transpapillary pancreatic duct drains or stents. Twelve of these patients had undergone a previous percutaneous or surgical pancreatic drainage procedure or both, and 8 had long-term drainage tubes in chronic fistulous tracts. Transpapillary catheters could be placed across the ductal disruption or directly into the fluid collection in each case, and 16 of 18 patients had resolution of the disrupted pancreatic duct. Twelve of 14 fluid collections resolved. Complications were limited to mild exacerbation of pancreatitis symptoms in 2 patients and 2 patients who developed subsequent stent occlusion leading to recurrent pancreatitis (1 patient) or recurrent duct blowout with pseudocyst (1 patient). Nine patients had variably significant ductal changes attributable to pancreatic duct stents. At a median follow-up of 16 months, 7 patients ultimately required surgery for ongoing pancreatic pain or residual/recurrent fluid collection. The transpapillary treatment of ongoing pancreatic ductal disruption with or without fluid collection has the potential to obviate surgery in some patients, change an urgent surgical procedure into an elective one, or even assist the surgeon in the performance of intraoperative pancreatography. Further study of this technique appears warranted and must be placed into the perspective of current therapies.

Acute Disease↗
PubMed1990

CT of the extrahepatic bile ducts: wall thickness and contrast enhancement in normal and abnormal ducts.

Recent reports have described thickening and enhancement of the extrahepatic bile duct wall on CT scans obtained after administration of IV contrast material. We undertook this study to establish parameters for the normal thickness and enhancement of the bile duct wall on CT, and to develop a differential diagnosis for thickening of the duct wall. Routine CT examinations of 100 patients without biliary disease were evaluated prospectively. The common hepatic duct and common bile duct could be visualized in 66% and 82% of cases, respectively; the walls of these ducts could be separately discerned in 59% and 52%. The mean thickness of the duct wall was 1 mm, with a maximal thickness of 1.5 mm. Wall enhancement was similar to (51%), slightly greater than (44%), or markedly greater than (5%) the enhancement of adjacent pancreatic parenchyma. A review of records covering a 5-year period identified 52 patients in whom CT showed thickening of the bile duct wall (greater than or equal to 2 mm). These patients could be categorized by seven underlying diseases, and analysis of the CT scans revealed four general patterns of thickening. Focal, concentric wall thickening in the distal common bile duct was associated with pancreatitis, pancreatic cancer, and common bile duct stones; focal, eccentric thickening tended to occur with cholangiocarcinoma and sclerosing cholangitis. Diffuse, concentric thickening was seen with acute cholangitis; diffuse, eccentric thickening was associated with oriental cholangiohepatitis and sclerosing cholangitis. Thickening of greater than 5 mm was seen only with cholangiocarcinoma. Enhancement of the duct wall in these groups varied and was of no predictive value. In summary, the extrahepatic bile ducts can be visualized in the majority of patients, and the normal duct wall should be 1.5 mm or less in thickness. Contrast enhancement of the duct wall occurs in patients without biliary tract disease and alone is predictive not predictive of pathology. Pancreatitis, pancreatic cancer, common bile duct stones, cholangiocarcinoma, sclerosing cholangitis, acute cholangitis, and oriental cholangiohepatitis are associated with thickening of the duct wall.

Acute Disease↗
PubMed1989

Failure of somatostatin or an analog to promote closure of end pancreatic fistulae.

Somatostatin has been reported to promote closure of pancreatic fistulae, but use of the analog SMS 201-995 (Sandoz, Inc.) has not previously been published. We used this analog to treat two patients with end pancreatic fistulae refractory to conventional therapy. One patient had disruption of a pancreaticojejunostomy after pancreaticoduodenectomy and the other had acute necrotizing gallstone pancreatitis and disruption of the pancreatic duct in the tail. SMS 201-995 (100-150 micrograms/d) abruptly decreased fistula output by 50% in both patients but further increases in dosage had no further effect on output. Neither fistula healed after 3-4 wk of therapy. Treatment with somatostatin or its analogs alone will not lead to closure of a pancreatic fistula complicated by factors such as distal obstruction, infection, or foreign body. Somatostatin may promote closure of lateral fistulae and may simplify the management of patients with high output fistulae.

Adenocarcinoma↗