Sections on Neurosurgery and Urology, Department of Surgery, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina

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1 J Nenrosurg 50: , 1979 Results of urinary diversion in patients with myelomeningocele HAROLD P. SMITH, M.D., JOHN M. RUSSELL, M.B., B.S., WILLIAM H. BOYCE, M.D., AND EBEN ALEXANDER, JR., M.D. Sections on Neurosurgery and Urology, Department of Surgery, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina Among 481 children with myelomeningocele seen at the North Carolina Baptist Hospital since 1949, 46 have undergone a urinary diversion procedure, as follows: ileal loop in 43; sigmoid loop in two; and transverse colon conduit in one. The indications for diversion were incontinence in 28, urinary infection or pyelonephritis in 27, and hydronephrosis, pyelocaliectasis, and reflux in 12 patients. No deaths resulted from the diversionary procedures. One patient required early surgical revision and seven patients required late surgical revision. Two patients have since died, 44 have been followed for an average of 7.9 years, 15 for more than 10 years. Overall, of 26 patients with normal prediversionary intravenous pyelograms (IVP's), 88% now have normal or nearly normal IVP's; of 14 patients with abnormal prediversionary IVP's, 79% now have normal, improved, or unaltered IVP's. Renal function has remained normal in all 44 patients, and renal calculi have developed in 10 patients. Ileal loop diversion appears to convert a high-pressure system into a low-pressure system, thereby helping to prevent further renal damage. This procedure tends to stabilize, rather than improve, urinary-tract function. For these children already so incapacitated by their basic disease, this goal is acceptable, particularly since it also provides continence and independence from parental nursing. KEY WORDS 9 myelomeningocele 9 urinary diversion 9 ileal loop 9 incontinence 9 bladder control M YELOMENINGOCELE occurs in one to six of every 1000 live births. Approximately 52% of infants with this anomaly do not survive. Half of those who die do so during the first 30 neonatal days; the predominant causes of death are other congenital anomalies, the myelomeningocele itself, and meningitis. Of those who survive for more than 30 days but die in infancy, death is most often due to hydrocephalus, followed by other congenital anomalies and severe myelomeningocele, or postoperative complications and pneumonia? That the neonatal mortality of patients born with myelomeningocele is lower now than it once was is due to the aggressiveness of present-day surgical treatment, a The child who thus survives is, however, continuously threatened by urinary-tract deterioration with incontinence and ultimately pyelonephritis and renal failure. Mebust, et al.) 2 reporting on 113 patients with myelomeningocele, found that by the age of 6 years, 41% of the girls and 18% of the boys had evidence of renal damage and upper urinary-tract deterioration. By 10 years old, 90% of the girls and 60% of the boys had hydronephrosis and pyelonephritis. In a series of 122 patients with myelomeningocele, Light and van Blerk 1~ found that vesicoureteral reflux extending into the renal pelvis with significant pelvis dilatation (Grade III reflux) and obstructive hydroureter were the most common factors associated with upper-tract deterioration. Of their patients, 11.8% had Grade III reflux in the neonatal period. Predictably, the greatest percentage of deterioration occurred over the first 2 years of life; there was a second small peak of deterioration at 4 years. The two most common means of managing those urinary problems have been urinary diversion and intermittent catheterization. Urinary diversion, popularized by Bricker x during the early 1950's, has recently fallen into some disrepute because of the late appearance of complications related to progressive upper urinary-tract dilatation, acidosis, and subsequent renal deterioration. In its place, clean, nonsterile intermittent catheterization has been suggested. 2,6 J. Neurosurg. / Volume 50 / June,

2 TABLE 1 Level and treatment of myelomeningocele Level & Treatment H. P. Smith, J. M. level lumbosaeral 21 lumbar 11 sacral 6 thoracolumbar 6 thoracic 2 treatment excision and closure < 3 months 38 (83 ~o) > 3 months 6 not excised or closed 2 The ultimate goals of any form of management of those problems are the achievement of continence, the provision of some degree of independence for the patient, and the prevention of upper urinary-tract deterioration and subsequent renal failure. We maintain that supravesical diversion in the form of ileal (and in more recent years, sigmoid colon) conduits has a definite place in the achievement of those goals. Patient Population Clinical Materials and Methods Four hundred and eighty-one children with myelomeningocele have been seen at North Carolina Baptist Hospital since Between 1959 and 1976, 46 of the children underwent urinary diversion procedures. Those 46 children form the basis of this report. There were 20 boys and 26 girls. The level and treatment of myelomeningocele are shown in Table 1. Hydrocephalus was found in 32 patients, 29 of whom required a shunting procedure. An ileal loop was established in 43 patients, a sigmoid loop in two patients, and a transverse colon TABLE 2 Preoperative neurological status at time of diversion Neurological Status flaccid paraplegia 28 (61 7o) flaccid paraparesis with hip flexors 8 weak dorsi or plantar flexors with neurogenic bladder 5 sacral anesthesia or decreased rectal sphincter tone with neurogenic bladder 3 neurogenic bladder only 2 Russell, W. H. Boyee and E. Alexander, Jr. conduit in one patient. Although all patients were incontinent, incontinence was the primary indication for urinary diversion in only 28 patients. In the others, the primary indication was urinary-tract infection or pyelonephritis in 27 patients, and hydronephrosis, pyelocaliectasis, and reflux in 12 patients. The average age at the time diversion was performed was 7.5 years (range 18 months to 19 years). The average age for social indications was 6.2 years and for architectural changes or renal damage, 8.6 years. Prediversionary management included Cred6's maneuver in 24%, and spontaneous or incontinent voiding in 100%. Six children had undergone previous urinary-tract operations. One of the total nephrectomies was of a nonfunctioning kidney with carbuncle, pyelonephritis, and calculi, the other was of a nonfunctioning kidney with hydronephrosis. The patient with bilateral partial nephrectomy had had bilateral duplication of the ureter and the lower pole of the kidney; the operation was carried out when he Was 3 months old. Neurological assessment of the patients before urinary diversion showed a range from flaccid paraplegia in 28 patients to neurogenic bladder only in two patients (Table 2). Most patients had an atonic bowel and required frequent enemas for adequate bowel evacuation. Preoperative assessment of urinary function included urine cultures, measurements of blood urea nitrogen (BUN) and creatinine, and intravenous pyelography (IVP) and cystography. Thirty-six patients had positive urine cultures; only six had abnormally high BUN levels (Table 3). Of 45 patients who underwent IVP, 27 showed normal findings. Abnormal IVP findings are shown in Table 4. Operative Procedure. The ileal loop diversions were classically performed with a short segment of terminal ileum normally supplied by two vessel arcades. The proximal loop was closed with two layers of absorbable catgut. The ureteroileal end-to-side anastomoses were performed with chromic catgut, and the ureteroileal anastomosis was placed retroperitoneally. Stents were usually left in each ureteroenteric anastomosis for 72 hours. For formation of the three colon conduits, a submucosal tunnel was made in the colon segment and the ureters were anastomosed without being tapered. The stoma was formed with suturing of the mucosa to the serosa to the subcuticular layer with no formal nipple. Drains were not placed routinely. Early Complications Operative Results No deaths resulted from the urinary diversion procedure. During the first 6 weeks, one patient developed a ureterocutaneous fistula, ureteroileal stenosis, and subphrenic abscess. The entire loop was 774 J. Neurosurg. / Volume 50 / June, 1979

3 Urinary diversion in myelomeningoeele patients TABLE 3 Preoperative urine cultures and blood urea nitrogen (BUN) levels Results urine cultures (45 patients) positive 36 (78 Voo) negative 9 total 45 BUN (41 patients) < 20 mg~o 35 (85~o) > 20 mg~o* total 6 41 *Five patients had BUN levels of mgto; in one patient BUN was 60 mg~o. TABLE 4 Preoperative intravenous pyelography (IVP) in 45 patients Findings normal 27 abnormal 18 hydronephrosis 10 (bilateral in 6) reflux 3 hydroureter 2 pyelocaliectasis 2 nonfunctioning kidney 3 TABLE 5 Follow-up period after urinary diversion* Duration (yrs) No > 15 4 lost to follow-up review 2 *Average follow-up period was 7.9 years. Complications TABLE 6 Late complications electrolyte imbalance and acidosis (47o) 2 surgical (177o) 7 stenosis of stoma 2 pyocystitis 1 bilateral ureteroileal stenosis with stones 1 unilateral ureteroileal stenosis with hydronephrosis 1 leaking distal ureter 1 herniation of loop 1 renal calculi (22~o) I0 < 5 yrs postop 4 > 5 yrs postop 6 revised 1 month postoperatively. The only other early complications were minimal respiratory problems and ileus. Late Complications The range of follow-up periods is shown in Table 5, the late surgical complications in Table 6. The two cases of stomal stenosis were revised successfully. The patient with pyocystitis required a vaginal vesicostomy 1 year postoperatively; the patient with bilateral ureteroileal stenosis required revision 2 years later; the patient with unilateral ureteroileal stenosis required revision 7 weeks after operation. The leaking ureter was revised 5 months after operation; that patient developed a small-bowel obstruction secondary to adhesions; after laparotomy and lysis of the adhesions she has done well. A high incidence of renal calculi (23%) was found in our group of patients when compared to that in other series, where the incidence was as low as 5%. 17 In the past, an association between the formation of stones and an abnormal IVP before urinary diversion has been alleged. However, in our patients there was an equal incidence of normal and abnormal prediversionary IVP's in the patients who formed stones. Seven of the patients (16%) have required surgical procedures for calculi. Renal function, measured by determination of serum creatinine and BUN levels, has remained normal. Results on the basis of postoperative IVP are correlated in Table 7 with IVP findings before urinary diversion. Of the 15 patients who have been followed for more than 10 years, 56% have a normal IVP, 25% show some deterioration, and 18% show improvement over the prediversion IVP's. Discussion The cause of upper urinary-tract deterioration in patients with myelomeningocele is related to the early development of a high-pressure system within the bladder. McGuire 11 suggests that the development of that high-pressure system is probably related to the failure of reflex inhibitors and of subsequently increased sensitivity of post-ganglionic parasympathetic nerve endings within the bladder wall. Those changes lead to a heightened response of the detrusor muscles to stretch, which is magnified by the increased alpha receptor activity in the denervated bladder. That response, together with failed reflex control of urethral closure, accounts for the initial overflow-type J. Neurosurg. / Volume 50 / June,

4 H. P. Smith, J. M. Russell, W. H. Boyce and E. Alexander, Jr. TABLE 7 Correlation of results with prediversionary intravenous pyelograms (IVP' s) Postoperative Findings No. % normal prediversion IVP normal 1~} minimal deterioration 88 frank deterioration 3 12 total 26 abnormal prediversion IVP normal i} improvement 79 no change frank deterioration 3 21 total 14 vesical emptying problems in those patients and the associated high-pressure reflux problems that result in upper-tract dilatation and ureterovesical obstruction. Thus, although the primary neurological defect in the patient with myelomeningocele is related to the lower urinary tract, treatment must be aimed at protecting the upper urinary tract. Apart from providing an easily manageable continence device, it appears that ileal loop diversion converts a high-pressure system into a low-pressure system, thereby helping to protect against further renal architectural damage. Its primary effect is not improvement of urinary-tract function as much as it is stabilization of such function. This result is shown in our patients and is confirmed by results in other reported series? '~4 ~s Table 8 shows that deterioration following urinary diversion was above 25% in only two of the series. The study by Schwarz and Jeffs 14 is interesting because theirs is the only series in which more of the patients with normal prediversion IVP's suffered deterioration of the urinary tract than patients whose IVP's had been abnormal before diversion. That change was obviously a factor of time, appearing in the overall group and in the longer follow-up group, but not in patients followed for an average of only 4.5 years. Shapiro, et al., ~ reported a 17% overall mortality rate in their series, a 4% operative mortality rate. Death was primarily due to azotemia and chronic renal failure. Their series also contained a significant rate of late surgical complications, with stomal obstruction occurring in 38%, ureteroileal obstruction in 22%, pyocystitis in 16%, bowel obstruction in 13%, and elongation of the conduit in 11%. They emphasized, however, that as long as the IVP's remained normal, creatinine clearance remained normal, thus demonstrating the ability of ileal loops to preserve renal function. In Smith's long-term followup study on 322 patients, 16 by 10 to 20 years postoperatively, 10% of the patients had died, 10% were hypertensive, and 5% had renal calculi. Sterile, intermittent catheterization has been used for many years to provide a low-pressure drainage system in paraplegic males? Lapides and his coworkers 79 have suggested that the principal cause of urinary infection in patients with residual urine is overdistention of the bladder, which creates poorly perfused areas in the mucosa that are susceptible to infection. They stated that intermittent complete emptying of the bladder should drastically reduce the number of urinary infections. Accordingly, they advocated clean, nonsterile intermittent catheterization as a means of preventing significant inflammatory changes in the bladder in patients with many types of Series TABLE 8 Correlation between prediversionary intravenous pyelograms (IVP's) and results of urinary diversion Follow-Up Period (yrs) Normal Preop IVP's Deterioration Deterioration Postop Abnormal Postop No. % Preop IVP's No. % Smith, t t Schwarz & Jeffs, (ave) 14t 2 14 ~ 34t / (ave) 1St J 23t Shapiro, et al., (ave) 72* * Kyker, et al, " " 3 14 Stevens & Eckstein, (ave) 35t t 8 17 Smith, 1978~t (5 yrs) 16 (5 yrs) 10 (10 yrs) 20 (10 yrs) 23 (> 10 yrs) 45 (> 10 yrs) Smith, et al., (ave) 26t t 3 21 *Number of renal units. tnumber of patients. ~;Brief report of 322 patients including long-term follow-up review of patients in Smith, 1972, series, 17 included to show the progressive deterioration of the urinary tract as the follow-up period lengthens. 776 J. Neurosurg. / Volume 50 / June, 1979

5 Urinary diversion in myelomeningocele patients neurogenic bladder. Drago, et al., 2 and Kyker, et al. 6 have discussed the use of that technique in patients with myelomeningocele. Kyker, et al., 6 reported that of 52 renal units of patients treated with intermittent catheterization, only two of the 46 that were normal originally showed evidence of deterioration with a maximum follow-up period of 2.5 years. Among the 52 renal units in patients undergoing supravesical diversion, 31 were originally normal; of these, 27 remained stable and four deteriorated. Of the six originally abnormal units in patients treated with intermittent catheterization, two remained stable and four improved, while of the 21 abnormal renal units in patients treated by diversion, 14 remained the same, four improved, and three deteriorated. The authors judged that 46% of the patients were satisfactorily continent on intermittent catheterization only, and 88% on intermittent catheterization and medications. The last finding is similar to that of Mulcahy, et al., 18 who reported a continence rate of 84% when patients being treated with intermittent catheterization were given oxybutynin chloride, an antispasmodic drug specific to the bladder. In contrast, only 26% of the 51 patients in the series reported by Drago, et al.,2 became completely continent on intermittent catheterization alone. The predominant reasons for failure were a small bladder with low-bladder outlet resistance, and unwillingness on the family's part to continue the procedure. Their 44 patients with previously normal IVP's had shown no signs of renal deterioration; of three with previously abnormal IVP's, two had improved, and one had shown deterioration. Those studies suggest that, in the short term at least, intermittent catheterization is as good as ileal loop diversion in providing renal protection, but it appears to be inferior overall in its control of continence and its provision of independence. Clearly, the proper management of these children should start with a urological assessment in the neonatal period, including IVP's with voiding films and estimation of renal function on the basis of BUN, creatinine levels, and creatinine clearance. Some estimation of tubular function should be made, since that variable precedes deterioration of glomerular function in most urological conditions, and is therefore more sensitive in detecting early damage, la These children should then be followed yearly with IVP's, an assessment of renal function, and cystography when indicated. They should also be assessed every 6 months with urine cultures and urinalyses. The importance of long-term follow-up review is illustrated by one patient in our series who had had no urological complaints until 19 years of age, when she developed progressively severe incontinence and proved to have pyelographic evidence of marked architectural renal deterioration. The parents of these children should be instructed early in Credr's maneuver for initial management. A trial of intermittent catheterization, where necessary, should certainly be instituted in the preschool years, but if it does not provide continence or if signs of upper urinary-tract deterioration develop, then supravesical diversion should be undertaken early. With the proper selection of patients at an early age (before the onset of renal deterioration and definitely before azotemia develops), and with a good surgical technique, the results of urinary diversion should be acceptable as demonstrated by our series. Further, the surgical procedure provides the patient with an independence difficult to obtain with intermittent catheterization. The outlook for those results is even better with the development of the antirefluxing colonic conduit, which, on short-term follow-up review, appears to provide superior protection of the upper urinary tract without sacrificing any of the advantages of the ileal loop diversion. It is currently our preferred diversionary procedure. At present, we agree with Shapiro, et al., ~5 that ileal conduit diversion, although a major surgical undertaking, remains the standard of urinary diversion against which all other methods must be judged. References 1. Bricker EM: Substitution for the urinary bladder by use of isolated ileal segments. Surg Ciin North Am 36: , Drago JR, Wellner L, Sanford E J, et al: The role of intermittent catheterization in the management of children with myelomeningocele. J Urol 118:92-94, Eckstein HB, Macnab GH: Myelomeningocele and hydrocephalus. The impact of modern treatment. Lancet 1: , Esho JO, Cass AS, Briggs PF: Myelomeningocele in Minnesota. Incidence and fate. Minn Med 58: , Guttmann L, Frankel H: The value of intermittent catheterisation in early management of traumatic paraplegia and tetraplegia. Paraplegia 4:63-84, Kyker J, Gregory JG, Shah J, et al: Comparison of intermittent catheterization and supravesical diversion in children with meningomyelocele. J Urol 118:90-91, Lapides J: Neurogenic bladder. Principles of treatment. Urol Clin North Am 1:81-97, Lapides J: Role of hydrostatic pressure and distention in urinary tract infection, in Kass EH (ed): Progress in Pyelonephritis. Philadelphia: F. A. Davis, 1965, pp Lapides J, Diokno AC, Silber S J, et al: Clean, intermittent self-catheterization in the treatment of urinary tract disease. J Urol 107: , Light K, van Blerk P J: Causes of renal deterioration in patients with meningomyeloceles. Br J Urol 49: , McGuire E J: Classification and current theory of neurogenic vesical dysfunction. Presented at the J. Neurosurg. / Volume 50 / June,

6 H. P. Smith, J. M. Russell, W. H. Boyee and E. Alexander, Jr. American Medical Association Postgraduate Course, San Francisco, Mebust WK, Foret JD, Valk WL: Fifteen years of experience with urinary diversion in myelomeningocele patients. J Urol 101: , Mulcahy J J, James HE, McRoberts JW: Oxybutynin chloride combined with intermittent clean catheterization in the treatment of myelomeningocele patients. J Urol 118:95-96, Schwarz GR, Jeffs RD: Ileal conduit urinary diversion in children: Computer analysis of followup from 2 to 16 years. J Urol 114: , Shapiro SR, Lebowitz R, Colodny AH: Fate of 90 children with ileal conduit urinary diversion a decade later: Analysis of complications, pyelography, renal function and bacteriology. J Urol 114: , Smith D: The long-term renal outlook following ileal conduit diversion. Br J Urol 50:69, 1978 (Proceedings) 17. Smith ED: Follow-up studies on 150 ileal conduits in children. J Pediatr Surg 7:1-10, Stevens PS, Eckstein HB: Ileal conduit urinary diversion in children. Br J Urol 49: , Walker D, Madorsky M, Fennell R, et al: Glomerular and tubular function in children with ileal conduit urinary diversion. J Urol 117: , 1977 Address reprint requests to: Harold P. Smith, Section on Neurosurgery, Bowman Gray School of Medicine, Winston- Salem, North Carolina J. Neurosurg. / Volume 50 / June, 1979