Biomedical subjects
H N Winfield
Publications and source records attributed to H N Winfield.
Laparoscopic partial nephrectomy: initial experience and comparison to the open surgical approach.
During an 18-month period, 6 laparoscopic partial nephrectomies were attempted, 4 of which were successful. The surgical technique was modified and improved between cases aided by new laparoscopic instrumentation, such as the argon beam coagulator and the 7.5 MHz. ultrasonic sector scanning system. In a retrospective comparison between laparoscopic and open partial nephrectomy, estimated blood loss was 525 ml. for the former versus 708 ml. for the latter procedure. However, operating time was more than 2 hours longer with the laparoscopic approach. The major advantages of the laparoscopic procedure appear to be a more rapid return to full diet, less postoperative pain and less requirement for parenteral narcotics. Despite the small size of this series and limited followup data, convalescence may be shortened by 4 weeks after laparoscopic partial nephrectomy. Patients with benign diseases of the kidney, especially with a duplicated collecting system, who require partial nephrectomy may be considered candidates for the laparoscopic approach. The advantages to the patient, however, may be offset by the technical demands on the surgeon.
Laparoscopically assisted penile revascularization for vasculogenic impotence.
Young patients with impotence and cavernous arterial insufficiency resulting from trauma-induced arterial occlusive disease are ideal candidates for microvascular arterial bypass surgery. To avoid the long abdominal incision required to harvest the inferior epigastric artery, a laparoscopic approach was used. We report a case of laparoscopically assisted penile revascularization for vasculogenic impotence.
Laparoscopic urologic surgery. The financial realities.
Since 1990, laparoscopic surgery has gained an important role in the specialty of urology. This article provides a financial analysis of the three most common urolaparoscopic procedures compared with their open surgical counterpart. The intraoperative costs of laparoscopic surgery are more expensive, but the postoperative expenses are less compared with open surgery. The financial ramifications of a shorter period of convalescence following laparoscopic surgery must be considered.
Laparoscopic approaches to the treatment of intrinsic urethral weakness (type III stress urinary incontinence).
The treatment of intrinsic urethral weakness (Type III stress urinary incontinence) has traditionally been accomplished by the performance of a sling cystourethropexy or the placement of an artificial urinary sphincter. As experience with operative laparoscopy continues to increase, the possibility of performing these procedures from a laparoscopic approach becomes realistic. We report our experience with the laparoscopic performance of a sling cystourethropexy and placement of an artificial urinary sphincter in the canine model. On the basis of initial results, we believe these techniques are feasible in human subjects.
Relationship of symptoms of prostatism to commonly used physiological and anatomical measures of the severity of benign prostatic hyperplasia.
In previous studies the severity of symptoms of prostatism in men with benign prostatic hyperplasia have not correlated well with prostate size, degree of bladder trabeculation, uroflowmetry or post-void residual volume. As part of a prospective cohort study of benign prostatic hyperplasia treatment effectiveness in 4 university-based urology practices, we correlated symptom severity and these commonly used measures of disease severity. Symptom severity was quantified using the American Urological Association symptom index. Analyses were based on 198 outpatients completing a standardized evaluation (84 of these men have completed 6 months of followup after treatment with prostatectomy, balloon dilation, terazosin or watchful waiting). At baseline, symptom severity was not correlated with uroflowmetry, post-void residual, prostate size and degree of bladder trabeculation. However, symptom severity was much more strongly related to overall health status than the other measures. Reduction in symptoms with treatment did correlate with improvements in uroflowmetry. This poor baseline correlation with symptoms may reflect unreliability in measurement of the physiological/anatomical variables. Alternatively, these parameters may be measuring different pathophysiological phenomena.
Peptidergic nerves in the ureter.
Vasoactive intestinal peptide (VIP) and substance P were demonstrated in the pig ureter by immunohistochemical techniques. Nerves containing these materials were related mainly to the smooth muscle layer in the normal and obstructed ureter. In isolated ureteral segments, VIP caused relaxation at doses exceeding 0.18 micrograms/ml, with no significant difference seen in the effect on normal and obstructed ureter. Vasoactive intestinal polypeptide may play a role in the regulation of ureteral smooth muscle tone.
Laparoscopic varix ligation.
Varicocele, dilated veins in the pampiniform plexus, is frequently a contributing factor in male infertility. We performed outpatient laparoscopic varix ligation in 14 patients (5 bilaterally) with clinically evident varices and persistent oligospermia and/or asthenospermia. The spermatic artery was identified and preserved in all but 1 varix ligation. Mean interval to resumption of preoperative activity levels was 3.4 days. On average, patients consumed 8.4 tablets of acetaminophen (325 mg.) with codeine (30 mg.) during the recovery period. The procedure is effective and decreases postoperative morbidity.
Laparoscopic varicocelectomy.
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Urological laparoscopic surgery.
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Construction of the intestinal stoma with an intraluminal stapling device.
We have used the intraluminal circular stapler to facilitate construction of the intestinal conduit stoma. We have encountered no complications related to the stapled stoma construction technique in 8 patients. The stoma is circular, uniform in size and is fitted easily with an appliance. The circular staple line provides a watertight seal that prevents contamination of the subcutaneous tissues. The technique is rapid, reliable and reproducible.
Urolithiasis: extracorporeal shock wave lithotripsy and endourologic techniques.
The author discusses effective treatment of stubborn kidney stones, utilizing extracorporeal shock wave lithotripsy augmented with traditional endourologic techniques.
Monotherapy of staghorn renal calculi: a comparative study between percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy.
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Biological markers in urologic cancer.
Tumor markers (TMs) play an important part in the management of urologic cancer. Alpha-fetoprotein, human chorionic gonadotropin, and occasionally lactic dehydrogenase serological determinations have become indispensable in the management of nonseminomatous germ cell testicular tumor patients, particularly after initial therapy, whereas human chorionic gonadotropin and probably placental alkaline phosphatase are important in seminoma. Prostatic acid phosphatase has long been important for the monitoring of patients with carcinoma of the prostate. The availability of the immunologic assays instead of the enzymatic assays has improved sensitivity somewhat but clinical interpretation has also become more complicated. Prostatic specific antigen is already an important tissue marker for carcinoma of the prostate and promises to be an important serological one, possibly surpassing prostatic acid phosphatase in importance. Analysis of DNA by automated flow cytometry is becoming important in the early detection and follow-up of bladder cancer patients. Studies concerning the tissue analysis of blood group antigens in bladder cancer continue to demonstrate that this approach can provide unique clinical information and interesting biological insights, but its role in routine clinical management remains to be determined. Currently, TMs have little clinical significance in renal cell carcinoma, but the availability of monoclonal antibodies to renal cell carcinoma preferential antigens may change this deficiency soon. In fact, in the near future, monoclonal antibodies will probably reveal many new substances for many urological cancers which can be used for markers serologically, histochemically, and, with their corresponding antibody, for radioimmune imaging and possibly immunotherapy. Now, as then, familiarity with the nuances of the marker and good clinical judgement will be essential.
Coexisting adenocarcinoma of prostate in patients undergoing cystoprostatectomy for bladder cancer.
The histopathology of the prostate in 80 men who underwent radical cystoprostatectomy for bladder cancer was evaluated. Twenty-two men had coexisting adenocarcinoma of the prostate; 11 had high-grade, large-volume disease. These data suggest that all prostatic tissue should be removed at cystoprostatectomy.
Percutaneous nephrostolithotomy: complications of premature nephrostomy tube removal.
Nephrostomy tube urinary drainage is important in the initial postoperative period after 1-stage percutaneous nephrostolithotomy. We report 2 cases in which nephrostomy tube drainage was not used after rapid removal of simple upper urinary tract calculi. The complications incurred resulted in prolonged hospitalization and marked patient discomfort.
Ultrasonic lithotripsy: the risk of hearing loss.
Ultrasonic lithotripsy has been applied widely to the percutaneous removal of upper tract calculi. The high noise levels generated by ultrasonic lithotriptors during clinical use have raised some concern among endourologists. In this study sound level measurements of all 3 commercially available ultrasonic lithotriptors were obtained in the audiology laboratory and operating room. In all circumstances the maximum noise levels recorded (103 dBA. or less) for the time of exposure that would be encountered in the clinical setting of ultrasonic lithotripsy never exceeded safe levels. We concluded that the routine use of ultrasonic lithotriptors does not present a hazard to the hearing of normal individuals.