Biomedical subjects
Publications and source records attributed to M Barkin.
Canadians have enjoyed a close and harmonious relationship with Americans for more than a century. We have learned and benefited greatly from our close association. We are pleased to share our experiences with the United States in the same spirit of mutual respect and support that has characterized our close relationship and opened our borders.
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Over a ten-year period, of more than 1,000 children whose primary vesicoureteral reflux was treated surgically, there were 54 children with 80 single ureters which were massively dilated. Primary reconstruction with ureteral tailoring was done in 25 ureters with a success rate of 92 per cent. Forty-five ureters were temporarily diverted because of uncontrolled infection and/or azotemia. In almost half of these instances, temporary diversion resulted in improvement in ureteral caliber to such an extent that nontailored reimplantation could be performed with a success rate of 87 per cent. Six kidneys were removed and four have been maintained in the diverted state with severe renal dysplasia. Eighty-eight per cent of the refluxing megaureters were reconstructed with a success rate of 89 per cent.
Permanent urinary diversion has been the standard recommended treatment of massive dilatation of the upper tracts in the child with neurogenic vesical dysfunction. Reimplantation of relatively normal caliber ureters into neurogenic bladders has been shown to be effective. However, attempts to save urinary diversion in 39 neurogenic megaureters have been unrewarding, with the salvage rate of 15 per cent, and 64 per cent have been diverted permanently. Upper tract decompression by continuous or intermittent catheterization, nephrostomy or end cutaneous ureterostomy was used in this series. When ureteral caliber responded to decompression a reasonable success rate from non-tailored reimplantation may be anticipated. However, in those instances in which ureteral caliber failed to respond or when tailoring or ureteral caliber was done in conjunction with reconstruction the success rate was much lower.
Of 105 boys with posterior urethral valves managed during a 10-year period most were managed by primary valve ablation. However, 39 of these boys required concomitant or additional procedures to 71 massively dilated ureters because of azotemia, infection and/or progressive upper tract deterioration. In 17 boys 25 ureters could be reconstructed primarily by varying degrees of ureteral tailoring. When there was severe infection, azotemia and/or doubt as to the function of the affected renal unit, staged reconstruction was initiated by cutaneous ureterostomy. One-fourth of these ureterostomy diverted children died of azotemia despite free urinary drainage. Those who went on to have staged reconstruction, despite multiple surgical procedures, retained intact urinary systems with acceptable function.
From 1965 through 1975 we treated 30 children with 44 megaureters that were acquired after the reimplantation of normal caliber ureters. One-third of these children had had at least 2 prior surgical procedures on the bladder and 30 per cent were azotemic. There was no difference in the salvage rate of acquired megaureters with reflux versus obstruction. Temporary proximal diversion often was useful in the short-term management. Only 70 per cent of the patients completed reconstruction and only 70 per cent of those reconstructed were successful by all parameters. Ureteral tailoring was generally a necessary adjunct to successful repeat reimplantation. There was a significantly lesser salvage rate in those ureters that had had more than 1 prior surgical procedure. The best results were obtained when all surgical maneuvers were done transvesically because there was a significant incidence of acquired atonic vesical dysfunction after repeated dissections in the perivesical area.
A unique case is described of traumatic disruption of an intact collecting system (calices, renal pelvis and ureter) from an intact kidney. Evidence is presented for a congenital weakness at the level of disruption.
From 1964 to 1975, of 83 children with primary megaureter 33 had unilateral and 8 bilateral massively dilated ureters that required surgical treatment, and of these 73% had febrile infection, 5% were septic and 10% were azotaemic. Surgical treatment consisted of ureteric reimplantation with excision of the atonic distal segment, preceded by diversion when indicated. Tailored reimplantation was successful in 98% of ureters and non-tailored reimplantation was uniformly unsuccessful. All failures were successfully corrected by tailored reimplantation. Thus the requirements for successful surgical management of massive ureteric dilatation in children secondary to an atonic ureteric segment are excision of the atonic segment, transvesical or extravesical tailoring of the ureter and reimplantation.
The electrohydraulic lithotrite generates high voltage discharges which, in a liquid medium, are converted to hydraulic shock waves capable of fracturing bladder stones. Electrohydraulic litholapaxy was successful in treating 28 of 30 patients with bladder stones. In nine patients other procedures were performed during the same anesthetic. In one patient, a calculus was removed from within a narrow-necked bladder diverticulum. Compared with conventional mechanical lithotripsy with serrated, jawed instruments, electrohydraulic lithotripsy is a safe, easy to learn and effective technique for treating bladder stones.
Fifteen boys with prune belly syndrome cared for over a ten-year period required surgical treatment because of uncontrolled infection and/or progressive azotemia. Five died of renal dysplasia. Primary or staged reconstruction resulted in significant improvement when ureteral reimplantation was combined with tailoring of ureteral caliber.
The massively dilated ureter is a major therapeutic challenge that faces the pediatric urologist. In those instances when more conservative measures, such as control of infection or correction of the primary pathology, have failed or are likely to fail surgical treatment must be directed to the massively dilated ureter itself. The goals of reconstructive procedures are the elimination of residual urine, effective ureteral peristalsis, and efficient and/or urgent urinary drainage. We encountered these clinical settings in 244 children with 366 massively dilated ureters from 1965 through 1974. The underlying pathologic processes included primary megaureter, refluxing megaureter, posterior urethral valves, ureteral duplication with upper role ectopic ureterocele or lower pole refluxing megaureter, simple ureterocele, ureterovesical junction obstruction, neurogenic vesical dysfunction, prune belly syndrome and acquired (iatrogenic) megaureter. The results of several reconstructive techniques are reviewed according to the excretory urogram, cystogram, renal function studies and the presence or absence of urinary infection. Analysis of the results with respect to the underlying pathologic entity responsible for the massively dilated ureter indicates that the etiology is a crucial factor in determining whether surgical treatment should be recommended and the type of surgical treatment that will most likely be successful.
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Current therapy for metastatic non-seminomatous testis tumors is effective but toxic. Careful investigation is needed to select those who need treatment and yet avoid needless toxicity in patients who have no disease. Current radiographic investigations and measurement of two biochemical tumor markers (AFP & BHCG) provided accurate monitoring in 19 patients. Preoperative urography and lymphography correctly predicted the presence or absence of retroperitoneal metastases in 9 of 12 patients but did not show microsocpic metastases in 3. There was good correlation between the clinical, readiographic and biochemical evidence of disease progression and regression. Serial ultrasonography and tumor marker determinations were particularly useful in following asymptomatic abdominal metastases. Radiography and tumor marker determinations each have specific advantages which make them complementary.
Vesical implantation and oral feeding studies in animals raised sufficient suspicion of the carcinogenic propensity of cyclamates to result in their withdrawal from sale throughout the world. The structural similarity to known carcinogens, an effect on human chromosomes in tissue culture and a high carcinogenic potential when combined with non-injurious co-carcinogens gave further support to this ban. On the other hand, numerous epidemiological studies failed to support any statistical relationship between cyclamate ingestion and vesical carcinoma in man. Three patients are described in whom vesical carcinoma developed after a prolonged period of ingestion of an unusually high amount of cyclamate sweetener. Moreover, the severity of the disease appeared to be proportional to the dose ingested. Although this is not a conclusive indictment of the role of cyclamates we believe that patients with bladder cancer should be questioned about intake of cyclamates either directly or in diet soft drinks.
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A selected group of congenitally dilated ureters was examined under light and electron microscopy, and the findings were compared to the clinicoradiologic features of each ureter. These dilated ureters exhibit qualitative and/or quantitative muscular deficiencies. The obstructed megaureters secondary to posterior urethral valves and the megaureters with reflux show non-specific pathologic changes in response to increased work load or decompensation but infection within the ureter is detrimental to the muscle cells. The ureters in babies with prune belly syndrome suffer from reduced muscle cell population and a distinct myopathy involving the myofilaments within the muscle cells. The dysplastic ureter is morphologically and end stage ureter wherein the muscle cells are severely compromised. Whether this is an underdevelopment or exhaustion from repeated infections is a matter for speculation.
The potential of electron microscopy in the study of ureteral dilatation is seldom exploited but ureteral biopsies from 29 congenitally dilated ureters were examined under light and electron microscopy. A correlation between the pathological findings and the result of the surgical correction of these ureters is shown. The prospects of ureteral functional recovery can be predicted when the muscle cell integrity is considered.