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Biomedical subjects

R D Williams

Publications and source records attributed to R D Williams.

At least 163 records · Page 9Linked to original sources
PubMed1983

Rupture of the corpus cavernosum: surgical management.

Rupture of the corpus cavernosum is an uncommon injury resulting from a direct blow to the erect penis. The injury is easy to recognize but treatment remains controversial. Our uniform operative plan, consisting of immediate exploration, identification, sharp débridement and primary repair of the tear in the tunica albuginea with absorbable sutures, resulted in preservation of normal penile erection in 7 patients. The hospital stay was brief (mean 3.8 days) and there were no complications. These results compare favorably to operative management as reported in the literature. Conservative management is associated with a 29 per cent complication rate and a mean hospital stay of 14 days. Therefore, early surgical repair of the rupture is advocated.

Adult↗
PubMed1983

Nuclear magnetic resonance imaging of the kidney: renal masses.

Fifteen patients with a variety of renal masses were examined by nuclear magnetic resonance (NMR), computed tomography, ultrasound, and intravenous urography. NMR clearly differentiated between simple renal cysts and other renal masses. On spin echo images, the simple renal cyst appeared as a round or slightly oval, homogeneous low-intensity mass with characteristically long T1 and T2 values. The thickness of the cyst wall was not measurable. The cyst had a smooth outer margin and a distinct, sharp interface with normal parenchyma. Hemorrhagic cysts were seen as high-intensity lesions. Renal cell carcinomas displayed a wide range of intensity. The T1 and T2 values of the tumors were always different from those of the surrounding renal parenchyma. Tumor pseudocapsule was identified in four of five patients examined. All carcinomas were accurately staged by NMR and extension of the tumor thrombus into the inferior vena cava was demonstrated. The authors predict that if these preliminary results are confirmed by data from a larger number of patients, NMR will play a significant role in renal imaging.

Adenocarcinoma↗
PubMed1983

Work in progress: nuclear magnetic resonance study of a paramagnetic nitroxide contrast agent for enhancement of renal structures in experimental animals.

A piperidinyl nitroxide stable free radical derivative, TES, was tested as an NMR contrast enhancer of renal structures in normal animals and animals with experimentally induced unilateral renal ischemia, renal vascular congestion, and hydronephrosis. Physiologic measurements indicated that TES is rapidly excreted in the urine with a clearance rate equal to the glomerular filtration rate. Because the compound is strongly paramagnetic, it increases the observable NMR intensity within the kidneys and urine in relatively low doses (0.04 to 0.9 g/kg). TES-enhanced spin echo renal images clearly demonstrated the presence of disease and functional abnormalities in diseased kidneys. These abnormalities were either not evident or only indirectly suggested on nonenhanced NMR images.

Animals↗
PubMed1983

Nuclear magnetic resonance imaging of induced renal lesions.

Nuclear magnetic resonance (NMR) images obtained after unilateral ligation of the ureter, renal artery, or renal vein in the rat were analyzed and compared with NMR images of the normal rat kidney. Anatomic and functional correlation of the induced renal lesions was made by concurrent CT and by gross examination of the excised kidneys. Many normal anatomic structures at the level of the renal hilum can be identified by high resolution NMR imaging. Differentiation of urine from renal parenchyma permits detection of gross changes both in renal function and in the mass of the renal parenchyma. NMR imaging is capable of diagnosing hydronephrosis, acute renal ischemia, and acute venous congestion in this rat model. In addition, a trend toward prolongation of the relaxation times T1 and T2 for abnormal renal parenchyma is demonstrated.

Animals↗
PubMed1983

Human renal carcinoma cells produce hypercalcemia in the nude mouse and a novel protein recognized by parathyroid hormone receptors.

When grown in nude mice, cultured renal carcinoma cells from a hypercalcemic patient produced marked hypercalcemia that was reversed by resection of tumor. Conditioned medium from this cell line contained a protein with activity in a renal adenylate cyclase bioassay for parathyroid hormone (PTH) which was blocked by the competitive PTH antagonist [8norleucyl, 18norleucyl, 34tyrosinyl]bPTH (3-34)amide. However, the biologically active protein was eluted from gel filtration columns as a larger molecular size component that PTH and was not recognized by any of four region-specific PTH antisera. The properties of this factor resemble those of the postulated PTH-like substance(s) in humoral hypercalcemia of malignancy.

Adenocarcinoma↗
PubMed1983

Nuclear magnetic resonance imaging in retroperitoneal fibrosis.

Three patients with biopsy-proven idiopathic retroperitoneal fibrosis were studied by computed tomography (CT) and nuclear magnetic resonance (NMR). The nuclear magnetic resonance images revealed the extent of the fibrous mass or plaque and showed that it involved the periaortic area in each case. The diagnostic information regarding the extent of the disease was similar to that derived from the x-ray CT. The NMR images demonstrated the relation of the fibrosis to the major retroperitoneal vessels in a fashion superior to CT. Furthermore, variation in intraluminal signals on multiple spin-echo parameters suggested the presence of abnormal flow in the vessel constricted by retroperitoneal fibrosis.

Aorta↗
PubMed1983

Anatomy and pathology of the male pelvis by magnetic resonance imaging.

Magnetic resonance imaging (MRI) of the male pelvis was performed in 25 subjects: five normal volunteers; six patients with carcinoma of the bladder; nine with benign nodular hyperplasia (including five with concomitant bladder carcinoma); nine with prostatic carcinoma; and one with a lymphocele after radical prostatectomy. The display of normal anatomy is enhanced by the ability of the MRI device to provide images in direct transverse, sagittal, and coronal planes. Sessile and pedunculated types of bladder carcinoma are readily shown due to the superior ability of MRI for soft-tissue characterization. Direct sagittal scans are advantageous for evaluation of tumors at the bladder base, and by combining two different planes of images, the extent of the neoplasm is better delineated. In the analysis of the prostate, MRI displays the gland in three dimensions and therefore allows accurate volumetric measurements. The greatest potential of MRI seems to be its ability to detect pathology confined to the gland. However, it is not yet known if a neoplastic nodule can be differentiated from chronic prostatitis. Unlike x-ray CT, metallic clips produce no streaking artifacts, giving MRI a definite advantage in the evaluation of patients after radical surgery. These observations were made on a small number of patients. If the results are confirmed with a larger number of patients, MRI will assume a prominent role in the clinical evaluation of bladder and prostate cancer.

Adult↗
PubMed1983

Dialyzability of methyl-GAG.

Methyl-GAG at low doses was administered to an anephric male patient with metastatic hypernephroma, who required hemodialysis. No toxicity was observed. Measurement of serum levels of methyl-GAG showed that the drug is dialyzable. Thus, when methyl-GAG is considered for patients who are anephric and are being dialyzed, full doses are allowable. In addition, dialysis should be effective in rapidly eliminating the drug in patients who develop toxic effects.

Adenocarcinoma↗
PubMed1982

Continuous flow and conventional resectoscope methods in transurethral prostatectomy: comparative study.

The continuous flow resectoscope is claimed to be superior to the conventional resectoscope with respect to blood loss, resection time and rate, and irrigant absorption. These purported advantages were tested by a study of the results of transurethral resection of the prostate in 36 patients assigned randomly to 2 groups: 1) 20 patients operated on with the continuous flow resectoscope and 2) 16 operated on with the conventional resectoscope. No statistically significant differences for blood loss, resection rate or irrigant absorption were found between the 2 groups. We concluded that the preference of the surgeon continues to be the most important determinant in instrument choice.

Body Weight↗
PubMed1980

Diverticula of the male urethra.

Recently, we have seen 8 patients, ranging in age from 4 to 72 years, who each had a diverticulum of the anterior urethra. Our experience with these patients, combined with a thorough review of the literature, has demonstrated that while the cause and classification of these lesions often are controversial, multifaceted and confusing, the best treatment may be determined simply through accurate description of the size, thickness and anatomic location. Many diverticula, regardless of their cause, are contained within an intact corpus spongiosum and can be treated successfully transurethrally. Those diverticula that may leave a cavity too large to drain well, are too thick to cut transurethrally or lack adequate surrounding supportive tissue are treated bet by open surgical excision and urethral closure.

Adult↗