PubMed Health⌕ Search

Biomedical subjects

P J Bryan

Publications and source records attributed to P J Bryan.

At least 19 recordsLinked to original sources
PubMed1990

Chemotherapy-based control of schistosomiasis haematobia. II. Metrifonate vs. praziquantel in control of infection-associated morbidity.

To determine the relative efficacy of metrifonate and praziquantel in controlling urinary tract morbidity due to Schistosoma haematobium infection, a random allocation treatment trial was performed among 1,813 school age S. haematobium-infected children from the Msambweni area of Coast Province, Kenya. Following baseline examination for infection, hematuria, proteinuria, and ultrasonographic urinary tract abnormalities, oral treatment with either metrifonate (10 mg/kg, repeated at 4 month intervals) or praziquantel (1 dose of 40 mg/kg) was given to infected subjects. Prevalence of morbidity was reassessed 12 months later for each treatment group. Results indicated equivalent patient improvement in response to either regimen: prevalence of hematuria fell from 75% to 17% after either praziquantel or metrifonate therapy. Similarly, prevalence of proteinuria was significantly reduced from 73% to 29% (metrifonate) or 27% (praziquantel) after therapy. Metrifonate and praziquantel caused similar reductions in bladder granulomata and bladder thickening; however, no reduction in hydronephrosis was noted with either drug. Analysis of outcomes in population subgroups defined by age, sex, pretreatment intensity of infection, or severity of pretreatment morbidity showed no consistent advantage for either drug. In this endemic area, both agents provide effective control of morbidity due to urinary schistosomiasis.

Adolescent↗
PubMed1989

Magnetic resonance imaging of rectal carcinoma.

Five patients with a diagnosis of rectal carcinoma were examined by magnetic resonance and computerized tomography (CT) to determine if magnetic resonance imaging (MRI) added any information to that obtained by computerized tomography. In each case, the imaging studies agreed with the surgical description of the tumor. The studies agreed on the presence of perirectal fat invasion and tumor position. Both modalities were positive for involved lymph nodes in the patient with metastatic disease to pelvic nodes, but both studies underestimated the number of nodes involved. These five cases were examined using two magnetic resonance scanners. The older one operated at 0.3 tesla (T) while the newer scanner operated at 1 T. Spatial resolution was improved with the newer scanner. In addition, the difference in signal intensity between tumor tissue and normal tissue was greater on the 1 T scanner. Tissue differentiation was useful in one case in which CT suggested extension of tumor into the vagina. The extension was confirmed on the MRI scan.

Adenocarcinoma↗
PubMed1988

Chemotherapy-based control of schistosomiasis haematobia. I. Metrifonate versus praziquantel in control of intensity and prevalence of infection.

To determine the effect of targeted field administration of oral chemotherapeutic agents on the prevalence, intensity, and morbidity of Schistosoma haematobium infections, we initiated a long-term school-based program in the Msambweni area of Kwale District, Coast Province, Kenya. Prior to treatment, 69% of the children examined (ages 4-21, n = 2,628) were infected; 34% had moderate or heavy infections (greater than 100 eggs/10 ml urine). Infected individuals were randomized to receive, during one year, either metrifonate (10 mg/kg x 3 doses) or praziquantel, (40 mg/kg x 1 dose). At the end of the first year, prevalence of infection fell to 19%; only 2% of the pupils remained in the moderately and heavily infected groups. Corresponding decreases in the prevalence of hematuria (54% in 1984 vs. 16% in 1985) and proteinuria (56% in 1984 vs. 26% in 1985) were noted. These were associated with significant declines in bladder thickening and irregularities noted during ultrasound examinations, but not with decreases in hydronephrosis. There was no significant difference in the post-treatment prevalence or intensity of infection after treatment with metrifonate as compared with praziquantel. These results demonstrate that field-applied chemotherapy with either agent offers a practical strategy for the control of S. haematobium infection and its associated morbidity.

Adolescent↗
PubMed1988

Ultrasound findings in the adreno-genital syndrome (congenital adrenal hyperplasia).

The adreno-genital syndrome (congenital adrenal hyperplasia) is caused by deficiency of an enzyme (usually C-21 hydroxylase) necessary for adrenal production of cortisol, which results in excessive accumulation of androgenic precursors. It is the most common cause of female pseudohermaphroditism. There have been a few sporadic reports of ultrasonic demonstration of enlarged adrenals in the adreno-genital syndrome. To determine whether ultrasonography could be used to establish or exclude the diagnosis, ultrasonic examinations were performed on eight newborn infants with ambiguous genitalia who were subsequently proven to have the adreno-genital syndrome. The adrenals were found to be enlarged in three patients, at the upper limit of normal in three patients, and in two infants the adrenals were well within normal limits in size. The uterus was identified in seven of the eight patients, but was not seen for technical reasons in one. It is concluded that ultrasound is useful in the evaluation of infants with congenital adrenal hyperplasia to establish the presence of a uterus and to demonstrate enlargement of the adrenals, but it should be cautioned that finding adrenals of normal size does not exclude the diagnosis. Key words ultrasound, adreno-genital syndrome, congenital adrenal hyperplasia.

Adrenal Glands↗
PubMed1988

Magnetic resonance imaging of ruptured Baker's cyst.

The clinical presentation of a ruptured Baker's cyst and of thrombophlebitis can be identical. Venography, arthrography, and more recently ultrasonography have been used to differentiate these two entities. We report a patient with a ruptured Baker's cyst who was also evaluated using magnetic resonance imaging (MRI). The soft-tissue abnormalities were better demonstrated by MRI than by the other imaging methods.

Adolescent↗
PubMed1987

Hemophilic arthropathy: assessment with MR imaging.

Fifteen patients with hemophilia, 14 of whom had hemophilic arthropathy, were examined with magnetic resonance (MR) imaging to determine if it could be used to assess hemophilic arthropathy, especially synovial hypertrophy and the status of the articular cartilage. Thirty-five joints of the appendicular skeleton were imaged. Four joints in two patients were clinically normal. Synovial hypertrophy was detected in 28 joints and appeared as areas of low to intermediate signal intensity on T1- and T2-weighted images, with foci of increased signal intensity on T2-weighted images (presumed to be due to areas of fluid or inflammation) in 16 joints. Abnormal articular cartilage was demonstrated in 26 joints; bone lesions, fluid collections, and joint space narrowing could also be seen. MR imaging appears to be useful in depicting the components of hemophilic arthropathy.

Cartilage, Articular↗
PubMed1987

Chondromalacia patellae: assessment with MR imaging.

Magnetic resonance (MR) images of the posterior patellar hyaline articular cartilage were obtained in 23 subjects to determine if MR imaging could accurately demonstrate the patellar cartilage. Arthroscopy was used as the standard of reference. Three subjects were asymptomatic volunteers. In the remaining 20 who had patellofemoral pain, arthroscopy was performed before MR imaging in seven and afterward in 12; one did not undergo arthroscopy. MR imaging showed focal areas of swelling of the patellar cartilage, focal hypointensity, surface irregularity, areas of thinning, and areas of cartilage loss with exposure of subchondral bone. The surgical findings agreed with those from MR images in all seven patients who underwent arthroscopy before MR imaging and in ten of the 12 who underwent surgery afterward. MR imaging is an accurate means of examining the posterior patellar cartilage and should be considered as an alternative to diagnostic arthroscopy when chondromalacia patellae is suspected.

Adolescent↗
PubMed1987

Juvenile rheumatoid arthritis: assessment with MR imaging.

Thirty-three joints of the appendicular skeleton in 15 children with juvenile rheumatoid arthritis were examined with magnetic resonance (MR) imaging to determine if it could demonstrate synovial hypertrophy and status of the articular cartilage. Presumed synovial hypertrophy was seen in 13 joints as masses of varying sizes of low to intermediate signal intensity on T1- and T2-weighted images; sometimes foci of increased signal intensity, most likely due to fluid or inflammation, were seen on T2-weighted images. Probable abnormal articular cartilage was detected in ten joints, and MR imaging also demonstrated epiphyseal overgrowth, bone erosions, joint effusions, and joint space narrowing. Because MR imaging appears to provide an objective method of evaluating both synovial hypertrophy and status of articular cartilage, it may prove to be useful in monitoring progression of juvenile rheumatoid arthritis and response to therapy.

Adolescent↗
PubMed1987

Magnetic resonance imaging of the prostate.

Magnetic resonance imaging was utilized in 18 patients with prostatic cancer and compared with the findings in normal volunteers (Pontes et al., 1985), benign prostatic hyperplasia (Hricak et al., 1983), acute prostatitis (Walsh and Jewett, 1980) and chronic prostatitis (ACS, 1986). Sixteen of the 18 patients with carcinoma demonstrated inhomogeneous signal intensity, however, a similar appearance was also seen in 5 patients with benign prostatic hyperplasia. It does not appear that magnetic resonance imaging is able to reliably differentiate benign from malignant prostatic disease. Extra-prostatic tumor extension and pelvic adenopathy was demonstrated and the technique offers promise for the pre-operative staging of patients with known prostatic carcinomas.

Acute Disease↗
PubMed1986

Magnetic resonance imaging of the prostate.

The prostate was examined by magnetic resonance imaging (MRI) in 33 subjects, including five normal volunteers, 18 with prostatic carcinomas, seven with benign nodular hyperplasias, two cases of acute prostatitis, and one case of chronic prostatitis. Of 18 prostatic carcinomas, 16 produced an inhomogeneous signal intensity, with areas of diminished signal on T1-weighted scans and usually increased signal on T2-weighted images relative to the rest of the prostate. However, a similar appearance was also seen in five cases of benign nodular hyperplasia. It is doubtful at present whether MRI is able to reliably differentiate benign from malignant prostatic disease. Extraprostatic tumor extension and pelvic adenopathy was well shown, and MRI is very promising as a method for the preoperative staging of known prostatic carcinomas.

Carcinoma↗
PubMed1986

Magnetic resonance imaging of the genitourinary tract.

MRI is in its infancy as a clinical imaging tool. It is undergoing intensive investigation in various areas of the body. Evaluation of the brain and spine is superb, and in some areas of the brain, like the posterior fossa, it is thought to be superior to CT. Evolving indications for body scanning include staging of pelvic malignancies, evaluation of liver malignancy, evaluation and staging of musculoskeletal problems, and, to a lesser degree, staging of renal malignancies and evaluation of vascular disease. The main problem in body imaging stems from image degradation because of respiratory motion that is transmitted to upper abdominal organs. Respiratory gating of image acquisition or utilization of short heavily T1-weighted pulse sequences will likely overcome this problem in due time. Minimizing motion artifact will make MR images comparable to, if not better than, CT images with regard to transverse anatomic display, and MR images have the added advantage of multiplanar scanning, which can be done directly, without need of additional computer reconstruction time and without having to move the patient. The second major problem in MRI is the lack of understanding of equipment potential. Unlike conventional radiography and CT, in which the behavior of the X-ray beam is understood with regard to image formation, in MRI new parameters are used to generate images. As stated earlier, MR signal intensity is due to hydrogen concentration, T1 and T2 relaxation times of the tissue, and flow of protons through the imaged volume. How these factors are weighted depends on pulse sequence selection, and thus image contrast and information content of the scans change. On the surface, these images display anatomic information as do other imaging modalities, but manipulation of pulse sequences may ultimately lead to the ability to demonstrate physiologic and chemical parameters previously unavailable in imaging. Current research is geared to help extract this data by testing new pulse sequences, using different types of receiver RF coils, and using MR-specific contrast materials. Minor MRI problems such as long scan times are being dealt with to decrease time to an acceptable length. The nonvisualization of soft tissue calcifications will probably remain a problem that may have to be weighed against other known advantages. At this time further research and clinical experience are the key to what is needed in MRI, to gain further knowledge with regard to imaging physiologic phenomena, such as flow and spectroscopy, and possibly to monitor the chemical basis of disease.(ABSTRACT TRUNCATED AT 400 WORDS)

Calcinosis↗
PubMed1984

Renal lymphangioma: a cause of neonatal nephromegaly.

A newborn male presented with bilateral nephromegaly and mild hypertension. Function of the right kidney was reduced on excretory urography. Ultrasound showed bilaterally enlarged kidneys with increased echogenicity and poorly defined corticomedullary junctions. Areas of decreased medullary enhancement were seen on CT. Renal biopsy demonstrated lymphangioma, probably arising from the peripelvic renal tissues.

Humans↗