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Biomedical subjects

W S Hayes

Publications and source records attributed to W S Hayes.

At least 37 records · Page 2Linked to original sources
PubMed1992

From the archives of the AFIP. Leiomyosarcoma of the retroperitoneum and inferior vena cava: radiologic-pathologic correlation.

Leiomyosarcoma is the second most common primary retroperitoneal tumor in adults. Retroperitoneal leiomyosarcoma exhibits three major growth patterns: (a) completely extravascular (extraluminal) (62% of cases), (b) completely intravascular (intraluminal) (5% of cases), and (c) extra- and intraluminal (33% of cases). The usual clinical manifestation is a large abdominal mass. Intraluminal leiomyosarcoma may be accompanied by symptoms referable to venous thrombosis. The variable gross features and potential for intravascular extension result in various radiologic appearances, the most common being a large, partially necrotic soft-tissue mass in the retroperitoneum with or without extension into the inferior vena cava. Computed tomography and magnetic resonance imaging typically show a nonfatty, necrotic retroperitoneal mass and a vascular component when it is present. Ultrasound and angiography may also be useful, especially if vascular involvement is suspected from other imaging studies. Treatment of choice is surgical excision, which is frequently impossible due to the invasiveness of the tumor. Prognosis is related to extent of invasion and the adequacy of resection. Long-term prognosis is poor, and most patients die of local recurrence or distant metastasis.

Angiography↗
PubMed1992

The natural history of renal lesions in von Hippel-Lindau disease: a serial CT study in 28 patients.

OBJECTIVE: Von Hippel-Lindau disease is a multisystem disorder predisposing to renal cysts and cancer. The growth and development of these renal lesions have not been documented previously. We reviewed serial CT scans to determine the rates and patterns of growth of renal lesions associated with von Hippel-Lindau disease. SUBJECTS AND METHODS: Twenty-eight patients with von Hippel-Lindau disease and renal involvement, including the spectrum from simple cysts to solid masses, had follow-up examinations for at least 1 year (mean, 2.4 years; range, 1-12 years) with serial contrast-enhanced abdominal CT. Renal lesions were measured and characterized. Surgical correlation was available in 12 patients. RESULTS: Two hundred twenty-eight lesions (eight lesions per patient) were detected. On the basis of their CT appearance, 168 lesions (74%) were classified as cysts, 18 (8%) as cysts with solid components, and 42 (18%) as solid masses. Among 12 patients with pathologic confirmation, the solid components of cystic lesions and solid lesions almost always contained renal carcinoma. The majority of cysts remained the same size (71%) or enlarged (20%); 9% became smaller or entirely involuted during the follow-up period. Although it is generally presumed that renal cysts are precursors to cancers, the transformation of a simple cyst to a solid lesion was observed in only two patients. Among the 42 solid lesions, all but two enlarged with time, with a mean doubling time of 10 months. CONCLUSION: The renal lesions associated with von Hippel-Lindau disease exhibited wide differences in growth. The majority of renal cysts grew slowly but some involuted. Transition to solid renal cancer was rare among cysts. Complex cystic and solid lesions contained neoplastic tissue that uniformly enlarged. These data may be used to help predict the progression of renal lesions in von Hippel-Lindau disease.

Adult↗
PubMed1991

From the Archives of the AFIP. Xanthogranulomatous pyelonephritis.

Xanthogranulomatous pyelonephritis is a form of chronic infection of the kidney and surrounding tissues characterized by destruction and replacement of renal parenchyma by lipid-laden macrophages. Gross pathologic features include massive renal enlargement, lithiasis, peripelvic fibrosis, hydronephrosis, and lobulated yellow masses replacing renal parenchyma. Typically, the disease is diffuse and has characteristic imaging features. Less commonly, the process is focal and is difficult to differentiate from malignant disease on radiologic studies. Ultrasound demonstrates renal enlargement with multiple anechoic or hypoechoic masses replacing the normal corticomedullary differentiation and a contracted pelvis. Peripelvic fibrosis may obscure acoustic shadowing from a central staghorn calculus. On computed tomographic scans, a staghorn calculus may be seen in a contracted renal pelvis of an enlarged kidney, with characteristic low-attenuation, peripherally enhancing rounded masses. Extrarenal extension of the inflammatory process is frequently seen.

Adult↗
PubMed1991

Gallbladder varices: imaging findings in patients with portal hypertension.

A retrospective review of the medical and imaging records of 50 patients with portal hypertension examined in the authors' department during a 2-year period identified six patients with gallbladder wall varices. Imaging studies performed in these patients included computed tomography (CT) (four patients), duplex and color Doppler flow (five patients), and magnetic resonance (MR) (four patients). Five of six patients with gallbladder varices had portal vein thrombosis. Anechoic areas within the gallbladder wall detected with ultrasonography could be distinguished from intramural edema by using duplex or color Doppler flow imaging in all five patients in whom it was used. Contrast material enhancement of these varices was detected with CT in three patients, two of whom also had adjacent mesenteric collaterals. Gradient-echo MR imaging (fast imaging in steady precession/fast low-angle shot) showed flow-related enhancement within the gallbladder wall in two patients. The presence of gallbladder wall varices may imply the presence of portal vein thrombosis. Since these varices can be a source of major blood loss, surgeons must be made aware of them when operating on patients with portal hypertension.

Adult↗
PubMed1991

MR imaging of the portal venous system: value of gradient-echo imaging as an adjunct to spin-echo imaging.

We evaluated the use of gradient-echo (GRE) as an adjunct to spin-echo (SE) MR imaging of the portal venous system. GRE imaging was performed in 31 subjects, 15 normal volunteers and 16 patients with documented portal venous disease (15 cases) or suspected disease (one case). Eight of 16 patients had venous thrombosis, five had focal thrombus, and three had complete occlusion. Six patients had extrinsic venous compression by tumor. Of the two other patients, one had an arteriovenous fistula and the other a falsely positive angiogram, suggesting portal vein occlusion. In normal subjects, GRE scans had excellent visualization of the portal venous system with high intravascular signal compared with surrounding tissues. Nine (60%) of 15 normal subjects and three patients had an artifact consisting of a curvilinear area of decreased signal that could mimic clot. In three of five patients with focal thrombus, clot was identified on GRE but not on SE images. In all three patients with occlusion, SE and GRE images demonstrated similar findings. In five of the six patients with extrinsic venous compression by tumor, SE and GRE studies showed similar findings. Of the two patients, an arteriovenous fistula was seen on GRE MR in one, and in the other, patency of the left portal vein was seen on SE and GRE images after angiography had suggested portal vein occlusion. Collateral vessels were seen in nine of 16 patients. In five of nine cases, GRE MR demonstrated more extensive collaterals than did SE MR. In summary, GRE MR provides a useful adjunct to standard SE MR imaging. Benefits include high contrast between vascular structures and surrounding tissues, reduced motion artifact, and rapid scanning within a breath-hold.

Adolescent↗
PubMed1991

Gallstone lithotripsy: results when number of stones is excluded as a criterion for treatment.

The Siemens Lithostar Plus protocol (Siemens Medical Systems, Iselin, NJ) allows investigators to perform gallstone lithotripsy on patients regardless of the number of stones they have, provided the stones occupy less than 50% of the gallbladder lumen. The purpose of this study was to determine the interrelationships between stone burden, fragmentation response, and stone-free rates when treatment is not limited to three stones or fewer. Of 200 patients initially examined, 80 (40%) underwent lithotripsy. The mean number of treatments per patient was 2.1, and the mean number of shock waves per patient was 7386. In 60 patients in whom 6-month follow-up was available, the overall stone-free rate, based on actual results, was 32% (19/60). The stone-free rates for solitary stones, two or three stones, and four or more stones were 50%, 12%, and 26%, respectively. Regardless of number of stones, patients who ultimately became stone free had significantly smaller mean fragment size (0.25 cm) 2 weeks after lithotripsy than did those who did not become stone free (0.51 cm). Retrospective volume analysis showed that seven (47%) of 15 patients with multiple stones occupying less than 2000 mm3 were stone free; none became stone free when this volume was exceeded. Lithotripsy remains a practical option for patients with solitary stones. Comparable stone-free rates to those achieved for solitary stones can be obtained in patients with multiple stones, regardless of their number, provided treatment is aggressive and the stone aggregate is less than 2000 mm3.

Adult↗
PubMed1990

From the Archives of the AFIP. Microcystic adenoma of the pancreas.

Microcystic adenoma is a benign pancreatic neoplasm typically seen in elderly women. Presenting symptoms and signs such as pain, weight loss, jaundice, and a palpable mass are usually observed, but the lesion may be incidental and does not necessarily require excision. The tumor is generally large and well demarcated. It contains innumerable small cysts, giving it a honeycombed appearance. On computed tomographic scans, the hypervascular tumor has attenuation values close to those of water before contrast material is administered, but it usually enhances afterward. On sonograms, it is often predominantly echogenic, although some larger cysts may be seen. A calcified central scar may be seen with either modality.

Cystadenoma↗
PubMed1990

From the archives of the AFIP. Malignant germ cell tumors of the ovary: radiologic-pathologic correlation.

Malignant germ cell tumors are the most common malignant ovarian neoplasms in girls and young women. The most well known of these neoplasms are dysgerminoma, immature teratoma, endodermal sinus tumor, and a mixture of two or more of these elements. All malignant germ cell tumors, especially immature teratoma, can be associated with mature (benign) teratoma. These tumors are generally large and have a complex but predominantly solid appearance on cross-sectional images. Elevated serum alpha-fetoprotein and human chorionic gonadotropin levels can help establish the diagnosis. Cystic areas of calcifications suggestive of mature teratoma do not exclude a co-existing malignant neoplasm.

Female↗
PubMed1990

Relationship between stone motion, targeting, and fragmentation during experimental biliary lithotripsy.

In vitro experiments in an anthropomorphic phantom were performed to clarify the relationship between stone motion, targeting, and fragmentation. Stone motion was minimized by pinning the stone against the dependent wall of a mock gallbladder cavity during shock wave treatment. Fragmentation was most effective (probably due to increased cavitation effects) when the shock wave traversed fluid at the point of its impact with a stone. The results suggest that treatment with the patient in the supine or oblique position may produce a better outcome than treatment in the prone position. Buoyant stones exhibited the greatest motion, which was often to-and-fro in nature. Although restricting the size of the mock gallbladder cavity reduced stone motion, maintaining a 1-cm fluid path was beneficial for achieving optimal pulverization.

Cholelithiasis↗
PubMed1990

Cavitation effects during lithotripsy. Part II. Clinical observations.

Cavitation effects during biliary lithotripsy can produce sonographically visible microbubbles. The relationship between microbubble formation and clinical outcome of gallstone lithotripsy performed with a commercial lithotriptor was studied in 50 treatments in 29 patients. Microbubble formation in bile was a useful predictor of successful stone fragmentation in 31 of 34 treatments. Microbubble formation in the liver correlated with transient hepatocellular damage (as indicated by a twofold rise in serum transaminase levels) immediately after seven of 10 treatments. Advancing the focal volume of the lithotroptor deeper into the patient (placing the stone at the proximal point of the focal zone) may be a useful strategy for reducing hepatic cavitation effects, which appear to be responsible for temporary hepatocellular damage.

Adult↗
PubMed1990

Extraadrenal retroperitoneal paraganglioma: clinical, pathologic, and CT findings.

Paragangliomas of the retroperitoneum arise from specialized neural crest cells distributed along the aorta in association with the sympathetic chain. In order to ascertain characteristic CT features of extraadrenal retroperitoneal paragangliomas to differentiate them from other retroperitoneal tumors, 31 discrete tumors and two cases of paragangliomatosis in 28 patients were reviewed retrospectively, and the CT features were correlated with clinical and pathologic findings. There were 16 men and 12 women. Average age was 37 years (range, 11-70 years). Twenty-four patients (86%) had hypertension. Of these, catecholamine levels were elevated in all 18 patients who had biochemical studies. Four patients (14%) had malignant paragangliomas. The discrete tumors were classified by location as suprarenal (26%), renal hilar (32%), or infrarenal (42%). Suprarenal paragangliomas could not be distinguished from the ipsilateral adrenal gland on CT. The average size of functional tumors was smaller (7.0 cm) than that of nonfunctional tumors (12.0 cm), but the sizes of the two groups overlapped. Smaller tumors were more likely to be homogeneous and have well-defined margins than were larger tumors. Our findings indicate that extraadrenal retroperitoneal paragangliomas are functionally active more often than previously reported and that they are readily detected by CT as soft-tissue masses closely associated with the entire length of the abdominal aorta. However, no CT feature was found that was unique for paraganglioma.

Adolescent↗
PubMed1987

MR and CT evaluation of intracranial sarcoidosis.

Fourteen patients with CNS manifestations of neurosarcoidosis were evaluated by MR imaging and CT. Evaluations were done on a 0.5-T superconductive magnet with T1- and T2-weighted sequences. CT with contrast was obtained in all patients. The granulomatous lesions were classified by location into basilar, convexity, intrahemispheric, and periventricular white-matter involvement. Hydrocephalus with or without an associated lesion was also noted. MR determined the presence of disease in all patients (100%), but was less accurate than CT in depicting disease in two patients (14%). CT determined the presence of disease in 12 patients (85%) and was less accurate than MR in delineating hypothalamic involvement in two patients and periventricular white-matter disease in three patients. There was great variability in the appearance of intracranial sarcoidosis on MR. Three patients had lesions that were isointense or hypointense (relative to cerebral cortex) on both T1- and T2-weighted images while nine patients had lesions that were hyperintense on T2-weighted images. Convexity involvement and hydrocephalus were well documented by both CT and MR. These results indicate that both MR and CT are helpful in fully evaluating a patient with suspected intracranial sarcoidosis.

Adult↗
PubMed1982

Alcohol abuse in adolescents.

The problem of alcohol abuse among teenagers is a major health concern in this nation. The primary care provider's role in prevention, early detection and referral is diversified. This role is tailored in response to the clinician's assessment of his or her target population, the practice setting and the community resources and referral possibilities. Prevention and early detection are primary goals, with the aim of achieving health coping strategies, improving school performance, preventing accidents, increasing meaningful socialization, and preventing serious pathological changes and death as realistic outcomes for adolescents.

Adolescent↗
PubMed1977

Media for an integrated nursing curriculum.

In conclussion, the media decision-making process for an integrated nursing curriculum is based upon the following steps: - An analysis of the philosophy and unifying strands in the conceptual framework of the curriculum model, - An evaluation of currently owned media in terms of the theoretical framework and educational objectives of the model, - An assessment of commercial media with realistic planning for purchase and/or production, and - The development of a systematic ongoing evaluation process by students, faculty, and nursing service personnel. The focus of this discussion has been clarification of the assessment and planning steps necessary in the media decision-making process for an integrated nursing curriculum. While these steps are applicable to any educational model, they have particular relevance to a curriculum model in which concept learning and interrelationships are stressed.

Audiovisual Aids↗