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Published on: January 7, 2019
Bladder and external urethral sphincter function after prenatal closure of myelomeningocele
Chester J Koh1, Roger E DeFilippo, Joseph G Borer
1Department of Surgery, Children's Hospital Boston, Boston, Massachusetts, USA. ckoh@chla.usc.edu
Insights
Prenatal closure of myelomeningocele is linked to increased risk of external sphincter denervation and detrusor overactivity. Close postnatal surveillance is crucial for these patients.
Area of Science:
- Urology
- Pediatric Surgery
- Neurology
Background:
- Myelomeningocele repair strategies have evolved, with prenatal intervention emerging as a novel approach.
- Understanding the urodynamic consequences of prenatal versus postnatal myelomeningocele closure is critical for patient management.
Purpose of the Study:
- To compare urodynamic findings in patients who underwent prenatal myelomeningocele closure with those who had postnatal closure.
- To evaluate lower urinary tract function in both cohorts.
Main Methods:
- Retrospective comparison of urodynamic studies.
- 5 patients with prenatal myelomeningocele closure were compared to 88 patients with postnatal closure.
- Patients had similar lower lumbosacral lesion levels.
Main Results:
- All 5 prenatally treated patients showed complete external sphincter denervation.
- 39% of postnatally treated patients lacked sphincter activity.
- All 5 prenatally treated patients exhibited detrusor overactivity, compared to 38% of postnatal patients.
Conclusions:
- Prenatal myelomeningocele closure is associated with a higher incidence of external sphincter denervation and detrusor overactivity.
- Patients undergoing fetal closure require immediate newborn urodynamic studies and close postnatal surveillance.
- Monitoring for spinal cord tethering, incontinence, and elevated detrusor pressures is essential.
Purpose:
We compared urodynamic findings in patients who underwent prenatal closure of myelomeningocele with those of patients who underwent postnatal closure, and equivalent lower urinary tract evaluations.
Materials And Methods:
Urodynamic studies of 5 patients (2 boys, 3 girls) who underwent prenatal closure of myelomeningocele were compared to those of 88 patients with similar level lesions who underwent repair postnatally between 1979 and 2002.
Results:
All 5 patients in the prenatally treated cohort had lower lumbosacral lesions on neurological examination. These patients displayed no evidence of electromyographic activity, indicating complete denervation of the external sphincter. In comparison 34 of the 88 patients in the postnatal cohort (39%) lacked sphincter activity at newborn examination, with similar findings noted at 1-year evaluation. In terms of bladder function all 5 patients in the prenatal cohort exhibited detrusor overactivity, compared to 33 of the 88 patients (38%) in the postnatal cohort at the newborn examination, with similar findings at 1-year evaluation.
Conclusions:
Fetal closure of myelomeningocele is associated with a higher incidence of complete denervation of the external urethral sphincter and detrusor overactivity compared to postnatal closure. Patients who undergo this novel procedure should undergo urodynamic studies in the immediate newborn period and should be under close postnatal surveillance to document possible tethering of the spinal cord, urinary incontinence and increased detrusor pressures.
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