Search PubMed⌕ Search

Biomedical subjects

B A Carroll

Publications and source records attributed to B A Carroll.

At least 109 records · Page 6Linked to original sources
PubMed1982

Ultrasonic detection of complications following umbilical arterial catheterization in the neonate.

Seventy-one neonates with umbilical arterial catheters received serial real-time ultrasound examinations in order that the identification and natural history of catheter-associated thrombosis could be prospectively evaluated. Twelve (17%) of the infants had clinically evident signs of vascular compromise. Ultrasound detected abnormal intravascular echoes or lack of expansile pulsation in 10 of these 12 (83%). Abnormal echogenic foci were consistent with thrombus and intimal dissection. Two infants without clinical evidence of vascular compromise had ultrasonic findings consistent with thrombus. The ultrasonically detected abnormalities persisted from two to 70 days.

Aorta, Abdominal↗
PubMed1981

Ultrasonic characterization of abdominal tissues via digital analysis of backscattered waveforms.

Ultrasonic waveforms backscattered from normal and abnormal livers and spleens were recorded in vivo with the aid of a high-speed data acquisition system. Frequency-domain analysis of the digitized waveforms was employed to derive values for mean spacing of ultrasonic scatterers in tissue. Amplitude-domain analysis yielded measures of mean amplitude and variance, an indication of the distribution of amplitude values. Studies indicated that cirrhotic liver is characterized by a higher mean amplitude, a broader amplitude distribution, and a larger mean scatterer spacing than normal liver. Amplitude- and frequency-domain statistics for livers with other diffuse disease processes or tumor, as well for abnormal spleens. also differed from those of normal tissues. These data give information which may not be evident from B-mode sonograms, and which appears to be related to histological features.

Computers↗
PubMed1980

Ultrasonic renal volumetry in children: accuracy and simplicity of the method.

Renal length and volume were determined with B-mode ultrasonography and manual planimetry. The accuracy of the technique was prospectively evaluated in 11 children in whom concurrent sonograms and excretory urograms were obtained. Sonographic renal volume correlated better with urographic renal volume (r = 0.89) than did sonographic and urographic renal length (r = 0.78). The technique provides rapid, noninvasive measurement of renal length and volume, and can be used to follow renal growth patterns in children.

Adolescent↗
PubMed1980

The ultrasonic appearance of extranodal abdominal lymphoma.

The sonographic manifestations of malignant lymphoma involving 70 extranodal sites in 51 patients are presented. Areas of involvement by nonHodgkin and Hodgkin lymphoma included the liver, spleen, kidneys, stomach, pancreas, and muscles. The sonographic appearance of lymphomatous lesions does not necessarily correlate with histologic subclassification. Similarly, atypical manifestations of lymphoma may resemble a variety of neoplastic and non-neoplastic processes. Extranodal lymphomatous abdominal disease was detected in six patients whose lymphangiograms demonstrated no evidence of disease.

Abdominal Neoplasms↗
PubMed1980

Sonography of ventricular size and germinal matrix hemorrhage in premature infants.

Using the anterior fontanelle as an acoustic window, high resolution gray scale sonography brain scans with mobile apparatus were obtained in 35 premature infants. The sonographic technique provided accurate assessment of ventricular size and detected the subependymal germinal matrix and intraventricular hemorrhages. Ventricular size measurements correlated closely with computed tomography (CT) determinations (r = 0.83--0.92) in 29 infants. Sonography imaged the hemorrhages as areas of increased echogenicity with mass effect located characteristically in the region of the caudate nucleus. The size of the hemorrhages could be grossly estimated, but the full extent of hemorrhages was better delineated by CT. Sonography seemed superior in detecting small hemorrhages that were isodense with surrounding brain on CT. Despite its advantages of benignancy, accuracy, ease of examination, and cost, our sonography technique had limitations. False-negative sonograms occurred when the hemorrhage was located only in the posterior aspects of the ventricular system. Small hemorrhages in the caudate could be missed by either CT or sonography because of sampling error. Recognition of other disease processes was limited with sonography. The sonographic brain scan is a good initial test for high risk premature infants suspected of having subependymal germinal matrix and intraventricular hemorrhages. If the sonogram is negative or not typical for subependymal germinal matrix and intraventricular hemorrhages, CT is indicated.

Cerebral Hemorrhage↗
PubMed1979

Ultrasound appearance of decidual reaction in the uterus during normal pregnancy.

The sonographic appearance of the decidual changes undergone by the uterus during normal pregnancy is described in 88 ultrasound examinations on 75 obstetrical patients. The relation of these decidual changes to the site of placental implantation and their preferential location in the posterior uterus suggests that they represent a combination of choriodecidual sinuses and prominent draining uterine veins. The decidual reaction is most prominent between 18 and 32 weeks with a decline near term. There is also a wide variation in the extent of decidual reaction during normal pregnancy preventing its use as a sensitive indicator of normal versus abnormal pregnancy.

Decidua↗
PubMed1978

Biliary cystadenoma and cystadenocarcinoma: gray scale ultrasound appearance.

The gray scale echographic appearance of biliary cystadenoma/cystadenocarcinoma is described. The characteristic findings are a cystic, multiloculated intrahepatic mass with thick, highly echogenic internal septations. Findings are similar to those in pancreatic and ovarian cystadenomas/cystadenocarcinomas.

Aged↗
PubMed1978

Computerized cranial tomography in cerebral diseases of white matter.

Computerized tomographic scans were performed on 31 patients with primary diseases of the white matter. Among 18 patients with multiple sclerosis, acute lesions were visualized in five, all with symptomatic cerebral hemisphere disease. Characteristic white matter lesions were also demonstrated in adrenoleukodystrophy, spongiform encephalopathy, progressive multifocal leukoencephalopathy, disseminated necrotizing leukoencephalopathy, and an undiagnosed leukoencephalopathy associated with malignancy. Besides identifying white matter abnormalities, the CT scan patterns were often specific enough to help distinguish among the various etiologic possibilities for the abnormalities. Useful diagnostic characteristics included the anatomic distribution of lesions, mass effect, atrophic changes, and enhancement after contrast infusion.

Adrenal Insufficiency↗
PubMed1978

Gallstones: in vitro comparison of physical, radiographic, and ultrasonic characteristics.

An in vitro study of 30 gallstones was undertaken in which radiographic, ultrasonic, and physical characteristics were compared. Stones greater than 1 mm in diameter were consistently visualized in vitro using higher frequency transducers, lower intensities, and simple sector scanning techniques in different planes. All stones greater than 3 mm demonstrated consistent posterior acoustic shadowing, similarly facilitated by use of these techniques. The demonstration of posterior acoustic shadowing does not relate to the calcium content, shape, surface characteristics, or specific gravity of the stone.

Cholelithiasis↗
PubMed1977

Diagnosis of progressive multifocal leukoencephalopathy by computed tomography.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system which predominantly affects immunologically compromised hosts. The distinctive CT appearance in three documented cases includes low-density lesions of central and convolutional white matter with scalloped lateral borders. Lesions demonstrate no mass effect or contrast material enhancement. Findings are discussed with reference to other entities which may produce a similar CT appearance.

Adult↗
PubMed1975

Sialography: a simplified technique.

A simplified method of sialography is described. A wedged catheter tip positioned in the duct prevents backward leakage of contrast material into the oral cavity.

Humans↗