Early evolution of bladder emptying after myelomeningocele closure: Editorial comment

ing spinal cord injury, in Scientific Foundations of Urology, 3rd ed. Chicago, Year Book Medical Publishers, 1990, pp 286 – 299. 13. Mimata H, Satoh F, Tanigawa T, et al: Changes in rat urinary bladder during acute phase of spinal cord injury. Urol Int 51: 89 –93, 1993. 14. Houser EE, Bartholomew TH, Cookson MS, et al: A prospective evaluation of leak point pressure, bladder compliance and clinical status in myelodysplasia patients with tethered spinal cords. J Urol 151: 177–180, 1994. 15. Gross AJ, Michael T, Godeman F, et al: Urological findings in patients with neurosurgically treated tethered spinal cord. J Urol 149: 1510 –1511, 1993. 16. Zoller G, Schoner W, and Ringert RH: Pre- and postoperative urodynamic findings in children with tethered spinal cord syndrome. Eur Urol 19: 139 –141, 1991. 17. Stafford SJ, Fried FA, Sackett CK, et al: Hydronephrosis in the asymptomatic neonate with myelodysplasia. J Urol 129: 340 –342, 1983. EDITORIAL COMMENT Meticulous lifelong urologic care is mandatory for every patient with spina bifida. It is well recognized that good urologic care can virtually always prevent deterioration of renal function and end-stage renal failure. This care must have already been started shortly after birth, and good observation of bladder emptying is one of the main issues in this period. Nevertheless, it is very difficult to draw conclusions from differences, as the authors observed, in preoperative and postoperative residual volumes. Urine production during the first 24 to 48 hours after birth can often be very low and thus will influence the measurements significantly, especially because the clean intermittent catheterization was done—as the authors state— on a more or less random basis and not directly postvoid. Also, it is very well possible that birth itself is enough trauma to the meningomyelocele to cause a spinal shock phase, and thus spinal shock could already (in part) be present preoperatively. Therefore, in my opinion, the comparison between the residual volumes directly postoperatively and several weeks later is of more value than the comparison before and after surgery, and the authors’ data clearly suggest the existence of a spinal shock phenomenon after myelomeningocele closure.

UROLOGY 58 (5), 2001

Assuming a spinal shock-like mechanism after spina bifida closure, it has long been our routine to perform the first urodynamic study at age 3 to 6 months. In the absence of other signs of upper tract abnormalities, poor bladder emptying or urinary tract infections, we believe that this does not impose risks of (later) deterioration of renal function. As the authors stated, the interpretation of urodynamic studies in very young children can be quite difficult, and therefore the urologic therapy should always be individually tailored considering not only the urodynamic findings, but also multiple renal and bladder ultrasound scans, the voiding cystourethrogram, and the clinical picture (eg, voiding pattern, volumes obtained at clean intermittent catheterization). Futhermore, even if the situation appears to be completely stable and safe for the upper tract, meticulous follow-up remains mandatory, since the neuropathic bladder condition may change in time (eg, because of tethering of the spinal cord).

Robert P. E. de Gier, M.D. Pediatric Urology Center University Medical Center Nijmegen The Netherlands PII S0090-4295(01)01368-1 © 2001, ELSEVIER SCIENCE INC. ALL RIGHTS RESERVED

REPLY BY THE AUTHORS We agree with virtually all of the above comments. By our simple observations, we do not mean to suggest that anything other than meticulous follow-up of these patients, including urodynamic studies, is appropriate. We do believe that bladder emptying changes temporarily after myelomeningocele closure and that the changes are probably due to a problem similar to spinal shock. Clearly, frequent serial urodynamic studies would be necessary to define the etiology of the changes. PII S0090-4295(01)01369-3

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