A prospective evaluation of leak point pressure, bladder compliance and clinical status in myelodysplasia patients with tethered spinal cords.

We evaluated prospectively 26 patients with myelodysplasia and a tethered spinal cord to determine whether surgical release of the tethered cord positively influenced leak point pressure, bladder compliance, upper tract status and/or clinical management. Urodynamics were performed immediately before and after the neurosurgical procedure, and at 3 and 6 months postoperatively. Mean patient age was 7.8 years (range 2 days to 34 years) and median interval from onset of symptoms to surgery was 60 days (range 2 days to 4 years). Patient presentation included a combination of orthopedic, neurological and urological symptoms. Of 26 patients 9 (35%) had new hydronephrosis, urinary tract infections or urinary incontinence. Leak point pressure and bladder compliance did not change significantly by 6 months postoperatively. Of the 4 patients who presented with hydronephrosis 1 worsened in status, 2 stabilized and 1 improved. Clinical status was unchanged in 16 patients, improved in 4 and worsened in 6. There was no significant relationship between patient age and urodynamic or clinical outcome. Among patients followed for at least 6 months radiographic and clinical improvement occurred in 25% and 15%, respectively. Urodynamic improvements were transient. Surgical release of a tethered cord improved the urological status in less than a quarter of the patients in this series.