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Biomedical subjects

G A Schuster

Publications and source records attributed to G A Schuster.

12 recordsLinked to original sources
PubMed1999

The relative amount of epithelium, muscle, connective tissue and lumen in prostatic hyperplasia as a function of the mass of tissue resected.

PURPOSE: The relative amounts of epithelium, connective tissue, muscle and gland lumen in benign prostatic hyperplasia have been reported but they have not been correlated with prostate size. We determine if the relative amount of prostatic tissue varies with prostate size. MATERIALS AND METHODS: Paraffin blocks of transurethrally resected prostate tissue were randomly chosen from the archives of 58 patients with benign prostatic hyperplasia. Two new slides per patient were made and stained with prostate specific antigen or Masson trichrome, respectively. A total of 20 images from each slide were captured using a high resolution camera, digitized and analyzed with computer software for the relative percentage of the various tissue components. RESULTS: As the amount of prostate tissue resected increased from less than 10 to greater than 70 gm. the epithelium had a 4-fold increase from 5.37 to 21.92%, the muscle component had a 42% decrease from 28.46 to 16.62%, the lumen doubled from 7.05 to 14.01% and the connective tissue remained relatively unchanged from 35.58 to 31.53%. There was a statistically significant difference in all components of prostatic tissue except for connective tissue when comparing prostates less than 30 versus greater than 30 gm., including epithelium 6.52 versus 16.10% (p <0.01), muscle 28.45 versus 20.78% (p <0.01), lumen 7.42 versus 14.58% (p <0.01) and connective tissue 35.74 versus 32.45% (p <0.06). The stroma-to-epithelium and muscle-to-epithelium ratios each had a 9-fold decline (p = 0.01). CONCLUSIONS: As the prostate increases in size, there is statistically significant more epithelium and lumen, and less muscle tissue.

Connective Tissue↗
PubMed1995

Preparation of outpatients for excretory urography: is bowel preparation with laxatives and dietary restrictions necessary?

OBJECTIVE: The purpose of this study was to determine whether routine bowel preparation with laxatives and dietary restrictions (liquid supper and fasting after midnight) are necessary for satisfactory visualization of the urinary system during excretory urography in outpatients. SUBJECTS AND METHODS: Two hundred and four consecutive patients who had excretory urography were randomly placed in one of four groups before the examination. Eleven patients were excluded from the study for various reasons. The remaining 193 were divided into four groups. Groups 1 (50 patients) and 2 (45 patients) had bowel cleansing; groups 3 (49 patients) and 4 (49 patients) did not. Groups 1 and 3 were allowed to eat; groups 2 and 4 were given a liquid supper and fasted beginning at midnight the night before the examination. Standard radiographs and tomograms were obtained. Upon completion of excretory urography, the radiographs were reviewed and graded by one radiologist, who did not know to which group each patient belonged. A detailed, anatomically based grading system was developed and used to grade the radiographs. The radiographs of the kidney were divided into upper, middle, and lower margins; images of the calices were divided into upper, middle, and lower segments; images of the renal pelvis were divided into central and medial margins; images of the ureter were divided into upper abdominal, lower abdominal, upper pelvic, and lower pelvic categories; and images of the bladder were divided into full and empty categories. A score of 1 was given to each section visualized. The right and left sides of the urinary system were scored separately but added together for statistical analyses; therefore, the highest total score possible was 28. RESULTS: In the ability to visualize the anatomic structures on excretory urograms, there was no statistically significant difference (p = .06) between images of patients who were allowed to eat (groups 1 and 3, 99 patients, mean score = 27.49 +/- 0.92) and images of patients who were given a liquid supper and then fasted from midnight the night before excretory urography was performed (groups 2 and 4, 94 patients, mean score = 27.16 +/- 1.45). Moreover, there was no statistically significant difference (p = .16) between those patients given laxatives before the examination (groups 1 and 2, 95 patients, mean score = 27.45 +/- 0.93) and those not given laxatives (groups 3 and 4, 98 patients, mean score = 27.20 +/- 1.43). CONCLUSION: Our results show that bowel preparation with laxatives and dietary restrictions do not improve visualization of the urinary tract on excretory urograms obtained in outpatients. We conclude that such preparation in this group of patients was unnecessary and that it need not be performed routinely.

Adolescent↗
PubMed1988

Nephrogenic metaplasia of urinary tract in children: report of three cases and review of the literature.

Nephrogenic metaplasia of the urinary tract, originally thought to be a benign tumor with possible malignant potential, is commonly called nephrogenic adenoma. It predominantly affects male adults and is rarely seen in children. In this report 18 pediatric cases are reviewed and some clinical and pathologic parameters are compared with the condition in adults. Male to female ratio is reversed (3.7:1 in adults and 1:3.5 in children). Recurrences are more common and are more frequently multiple in the pediatric age group. Although no malignant transformation has been reported, prolonged follow-up is recommended since the natural history of this lesion is still uncertain.

Child, Preschool↗
PubMed1987

Clinical significance of hematuria in patients on anticoagulant therapy.

We evaluated 29 consecutive patients in whom gross or microscopic hematuria developed while they were on heparin or warfarin anticoagulant therapy. Patients who had bleeding as a result of anticoagulant overdosage and/or from an additional organ system(s) other than the urinary tract were excluded from this review. Significant pathological findings consisting of carcinoma, calculi, renal infarction, infection, benign prostatic hyperplasia and/or adult polycystic renal disease were identified in 17 patients. Insignificant or incidental pathological findings classified as posterior urethritis, simple renal cyst or renal scarring were noted in 6 patients. No pathological condition was found in the remaining 6 patients. We conclude that a thorough and appropriate evaluation of the urinary tract should be conducted in patients on anticoagulant therapy who have gross or microscopic hematuria, since a pathological lesion of variable clinical significance often is discovered.

Adult↗
PubMed1984

The radiologic diagnosis of complications following gynecologic surgery: radiography, computed tomography, sonography, and scintigraphy.

673,000 hysterectomies were done in the United States in 1981. The mortality rate of 16.4/100,000 was less than that for appendectomy. Gynecologic surgery, however, is the most common surgical cause of complications related to the urinary tract with the reported incidence varying from less than 1 to 10%. We reviewed the charts of 1403 patients who had 736 abdominal, 315 vaginal and 143 radical or modified radical hysterectomies. Seventy (5%) patients had complications. Thirty-two (2.2%) patients had 35 complications related to the urinary tract. Complications directly related to surgery were grouped into ureteral injuries (13), fistulas (10), post surgical fluid collections (13), and hydronephrosis following radical hysterectomy. Characteristic images obtained by radiography, sonography (US), computed tomography (CT), and nuclear medicine (NM) are presented, and their use in each group of complications is summarized in the conclusion.

Ascites↗
PubMed1983

Dissolution of renal calculi with dicloxacillin.

A patient with multiple left renal calculi and Staphylococcus epidermidis urinary tract infection is described. Subsequent treatment consisted of dicloxacillin which resulted in complete dissolution of all renal calculi. The rationale, supporting data, and potential therapeutic uses are reported.

Adolescent↗
PubMed1983

Unicaliceal kidney associated with posterior urethral valves.

Unicaliceal kidneys are normal in several mammals, including monkeys. There have been 10 patients with this anomaly reported on in the literature and most have had additional anomalies of the urinary tract. We report on a man with a unicaliceal kidney who also had posterior urethral valves.

Adult↗
PubMed1979

Computed tomography staging of renal carcinoma.

The ability of fast thire-and fourth-generation scanning devices to supply images of sufficient quality to delineate the kidney, its vascular supply, and surrounding fascial envelope has provided a modality which permits preoperative staging of tumors of the kidney with an accuracy of about 90% in limited series of 20 specimen cases. The unreliability of bolus injection to evaluate tumor extension to the renal vein accounted for two errors.

Adenocarcinoma↗