Detrusor Pressures Change with Repeat Filling Cystometry in Myelodysplastic Children with Neurogenic Lower Urinary...

The International Children's Continence Society recommends urodynamics repeated at least twice for the optimal result. We aimed to search if 3 times repeat filling urodynamics in the same session would change the urodynamics parameters in children with neurogenic lower urinary tract dysfunction due to myelodysplasia.

We investigated urodynamic reports and charts of 80 consecutive children with neurogenic lower urinary tract dysfunction due to myelodysplasia who underwent 3 repeat, same session filling cystometry studies between June 2017 and December 2018. Maximum detrusor pressure, maximum cystometric capacity, detrusor leak point pressure, compliance, residual urine volume and maximum cystometric capacity/estimated bladder capacity for age ratio were compared among all 3 filling cystometries.

The median age was 4.3 years (IQR 5.8). Of the patients 39 (48.75%) were girls and 41 (51.25%) were boys. Primary pathological finding was myelomeningocele in 69 patients (86.3%). Maximum cystometric capacity, compliance, residual urine and maximum cystometric capacity/estimated bladder capacity for age were found comparable in 3 repeat cystometries. However, maximum detrusor pressure at first filling was higher compared to others (second, p=0.015, and third, p=0.002). Detrusor leak point pressure at the first filling was also higher compared to the third (p <0.001). Detrusor overactivity was persistent in all 3 fillings in 85% of patients (68 of 80). Of the patients 68 (85%) remained in the same risk group according to detrusor leak point pressure (cutoff 40 cmH₂O).

Maximum cystometric capacity and detrusor overactivity are comparable in 3 repeat cystometries but detrusor pressures significantly decrease in the repeat fillings. In our practice we plan our management according to the most worrisome urodynamics parameters for a safer proactive approach.