Biomedical subjects
Publications and source records attributed to H N Whitfield.
This report describes the design, availability, repair facilities and costs of rigid ureteroscopes. Clinical factors affecting design are detailed. A classification is given. A new test of flow dynamics is described. Short operating ureteroscopes with a stable or integral telescope system appear to be superior to other types, especially as they may be used for antegrade ureteroscopy.
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Fifty patients have been treated for upper tract urinary calculi by extracorporeal shock wave lithotripsy (ESWL) at the Devonshire Hospital lithotripter centre since November 1984. The average stay for an inpatient was 3 X 7 days. All patients suffered minimal postoperative discomfort and nearly all resumed normal activity within one day after discharge. Complications requiring auxiliary procedures were few. The procedure was found to be safe, cost effective, extremely well received by patients, and superior to all other methods of removing renal stones. This study confirms that treatment by ESWL is a specialised urological procedure that requires operators who are also trained in open, percutaneous, and ureteroscopic surgery and with a back up of a radiological team skilled in percutaneous renal puncture.
The effects of monopolar and bipolar diathermy were studied in laboratory animals. The power required to coagulate transected vessels in air was established and the effect of immersion in saline and water during electrocoagulation was investigated. Tissue heat conduction from each type of probe was measured and compared. Tissue damage was assessed by light microscopy of histochemically stained sections. The bipolar system operated at a lower power output (13 W) with less heat conduction, and was unaffected by the surrounding medium.
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One hundred and fifty patients with renal stones have been treated by percutaneous nephrolithotomy. Complete stone clearance was achieved in 130 cases (87%). The management of patients in whom stone removal was not achieved percutaneously and the complications of the procedure are discussed. Guidelines are set out for successful percutaneous nephrolithotomy.
Upper tract pressure flow studies in four clinically unobstructed ureters with double J stents in situ indicated that urinary flow occurred mainly around the stent and that there was significant vesicorenal pressure transmission. This study examined the dynamics of ureteric urinary flow and morphological effects consequent upon stenting a ureter in vivo. In a porcine model, ureteric intubation caused a rise in intrapelvic pressures, hydroureter, vesicorenal reflux and generalised thickening of the ureteric wall with characteristic histological changes in the urothelium. These findings suggest that double J stents may compromise urinary drainage when ureteric obstruction is not present, urging caution in their use in the damaged, unobstructed upper urinary tract.
Thirty-one patients with urodynamically proven bladder outflow obstruction were treated with Alfuzosin in a 3-month, double-blind, placebo-controlled study. The irritative symptoms of bladder outflow obstruction were improved significantly in the treatment group, according to both objective and subjective evaluation. There was no objective evidence of a reduction in outflow resistance or obstruction in either group.
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Thirty consecutive patients with newly diagnosed symptomatic, locally advanced or metastatic prostate cancer were treated with intranasal buserelin, a long-acting analogue of gonadotrophin releasing hormone, in divided dosages of either 600, 1000 or 1200 micrograms daily. Suppression of testosterone occurred in 1 of 5 patients treated with 600 micrograms daily and in all of 25 patients receiving 1000 or 1200 micrograms regimens. Two of 5 patients treated with the 600 micrograms regimen and 23 of 25 patients receiving the higher dosage regimens showed subjective and objective evidence of response. Follow-up was from 1 to 31 months. During this period 11 patients have relapsed. The mean duration of remission was 16 months. Buserelin offers an effective alternative of equivalent efficacy to conventional treatments for prostatic cancer, without any significant side effects.
The management and follow up of 200 consecutive patients with renal and ureteric calculi are presented. The primary treatment of 185 (92.5%) was by extracorporeal shockwave lithotripsy (ESWL), of whom three (1.6)%) with large calculi underwent percutaneous nephrolithotripsy (PCNL) prior to ESWL as a planned combined procedure. Twelve (6%) were treated by PCNL or ureterorenoscopy (URS) as their definitive treatment and three (1.5%) by conventional open renal and ureteric surgery. The average in-patient stay was 3.8 days and most returned to normal activity within one day of discharge. Of the 185 patients 102 (55%) required no analgesia after treatment by ESWL, 29 (15.6%) required parenteral analgesia and the rest were comfortable with oral non-narcotic medication. Thirty (16%) required auxillary treatment by percutaneous nephrostomy (PCN), PCNL and URS following ESWL for obstructive complications from stone particles. Two required further ESWL and one PCNL at three months for large fragments. Overall, open surgery was required for only 1% of renal calculi and 13% of ureteric stones. These results are consistant with the extensive West German experience confirming that most urinary calculi are now best managed by ESWL and endoscopic techniques. Where these facilities are available open surgery should only be necessary for less than 5% of upper urinary tract stones.
Hemorrhage within a renal angiomyolipoma alters its characteristic appearance. We present a case diagnosed preoperatively with computerized tomography and ultrasound.
The results of percutaneous pyelolysis in 28 patients are presented. There were 18 successful and 10 unsuccessful cases. The indications for the procedure are defined in the light of this analysis.
Repeated administration of long acting analogues of gonadotrophin releasing hormone diminishes gonadal function and in men decreases testosterone concentrations; for this reason the effect of the analogue buserelin was studied in prostatic carcinoma. Twelve consecutive patients with newly diagnosed locally advanced or metastatic carcinoma of the prostate were treated. Each patient received intranasal buserelin in divided dosages of either 600 or 1000 micrograms daily. Suppression of the gonadotrophins and testosterone occurred in all patients. Objective and subjective signs of regression of disease were seen in nine patients. Buserelin offers an effective treatment of metastatic prostatic cancer without the side effects and cardiovascular risks associated with oestrogen treatment.
Percutaneous nephrolithotomy is becoming an established technique for the surgical management of renal stones. In a series of 48 patients treated by this method a success rate of 89% was achieved after an initial learning phase. The technique is suitable to be practised in any Department of Urology.
Twenty-two consecutive patients with newly diagnosed symptomatic, locally advanced or metastatic prostate cancer were treated with intranasal buserelin, a long-acting analogue of gonadotrophin releasing hormone, in divided dosages of between 600 and 1000 micrograms daily. Suppression of testosterone occurred in 1 of 5 patients treated with 600 micrograms daily and in all 17 patients receiving 1000 micrograms daily. Two of 5 patients treated with the 600 micrograms regimen and 16 of 17 patients receiving the 1000 micrograms regimen showed subjective and objective evidence of disease regression. Follow-up was from 1 to 16 months (mean 7.1 months); 6 patients have relapsed during this period. Buserelin offers an effective alternative medical treatment of carcinoma of the prostate and, apart from impotence, does not have the side effects of oestrogens.
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In spite of improvements in the techniques of radiological, urodynamic and radionuclide investigations there are patients in whom it remains very difficult to determine whether upper urinary tract dilatation is associated with obstruction. We describe a technique for the long-term monitoring of renal pelvic pressures and compare the results of this investigation with other methods. We believe that this technique is more useful than standard urodynamic tests and is of particular value in patients with equivocal pelviureteric junction obstruction and in those who have undergone previous surgery.