Ultrasound Assessment of Detrusor Thickness in Children and Young Adults with Myelomeningocele L. Müller,* K. Abrahamsson, U. Sillén, B. Jacobsson, A. Odén and M. Hellström From the Departments of Pediatric Radiology and Pediatric Surgery, Queen Silvia Children’s Hospital and Department of Radiology, Sahlgrenska University Hospital, Sahlgrenska Academy at Göteborg University, Göteborg and Romelanda (AO), Sweden Purpose: We determine by ultrasonography the range of dT in carefully treated and followed children with myelomenin- gocele, and evaluate the role of such measurements for the understanding of bladder abnormalities in these patients. Materials and Methods: We studied 66 children and young adults with MMC (34 males and 32 females, median age 8.1 years, range 1.1 to 20.1). Detrusor thickness was measured with a previously established ultrasonographic technique and the results were compared to those in normal children. The variation in detrusor thickness with degree of bladder dysfunction as well as with bladder wall trabeculation, kidney function and anticholinergic treatment was studied. Results: The detrusor of the ventral wall was slightly thinner in children with MMC compared to normal. No significant variation in dT was found for different degrees of bladder dysfunction, bladder wall trabeculation, kidney function or anticholinergic treatment. Boys had thicker detrusor of the ventral wall than girls. Conclusions: Children with MMC, followed closely and treated according to international standards, do not acquire detrusor thickening as measured by ultrasonography. The detrusor thickness did not correlate with the degree of bladder dysfunction or renal function, or with anticholinergic treatment. Bladder wall trabeculation at VCU was not associated with bladder wall thickening on ultrasonography. We postulate that in a closely monitored and actively treated population of patients with MMC muscular hypertrophy and the development of connective tissue in the bladder wall is kept to a minimum. Key Words: child; meningomyelocele; bladder; muscle, smooth; ultrasonography C hildren with MMC have neurogenic bladder dysfunc- tion, which puts them at risk for renal functional deterioration due to obstruction, incomplete bladder emptying, vesicoureteral reflux and infection. Therefore, these patients are followed closely with urodynamic and radiological evaluation to detect changes in bladder function that could affect the upper urinary tract. 1,2 These children are also frequently evaluated with ultrasound of the urinary tract to determine kidney size, detect dilatation and evalu- ate bladder emptying. Measurement of bladder wall thickness with ultrasound is a new and promising technique for evaluation of the bladder. 3,4 Cvitkovic-Kuzmic et al found a statistically sig- nificant difference in mean detrusor thickness between children with normal urodynamics and those with nonneu- ropathic bladder/sphincter dysfunction. 5 We have developed a standardized method for measuring dT of the bladder wall. 4 Using this method, we have previously determined reference values for children. 6 In the present study we mea- sured the range of dT and assessed the role of such mea- surements for understanding bladder abnormalities in carefully treated and followed children with MMC. MATERIALS AND METHODS Methods, definitions and units conformed to the standards recommended by the International Continence Society, 7 ex- cept when otherwise noted. This was a prospective study, from September 2001 to March 2003, of 66 children and young adults (34 males and 32 females 1.1 to 20.1 years old, median age 8.1 years). Patients were born with open MMC in the southwestern part of Sweden, and were attending a urological followup program at the Rehabilitation Center for Children and Adolescents With Neurogenic Bladder Dys- function. Of 135 patients 40 were excluded due to limitations in resources, and 14 were excluded due to a history of blad- der augmentation. The remaining 81 patients were sub- jected to measurements of dT as part of their annual urological evaluation. The ultrasound documentation from each case was reviewed by the prime investigator (LM) together with the urotherapist who had performed the ex- amination. In this evaluation 15 patients were excluded for examination quality reasons. The remaining 66 patients had acceptable measurements of the ventral wall and were in- cluded in the study. Most children started on CIC during infancy. Cystometry was performed at 0, 4, 10 and 18 months, and annually thereafter. Urinary continence was assessed by pad tests at age 3 to 4 years. VCU was performed in all children during the first year of life, and if recurrent urinary tract infections occurred, VCU was repeated. Upper urinary tracts were evaluated every other year with dynamic renography, CrEDTA clearance and ultrasonography. Lower level for glomerular filtration rate reference values for age using Submitted for publication May 24, 2005. Supported by grants from Göteborg Medical Society, Swedish So- ciety of Medical Radiology and Sahlgrenska Academy at Göteborg University, and funding from Västra Götaland Region under the LUA agreement. Study received ethics committee approval. * Correspondence: Department of Radiology, Hospital of Varberg, Träslövsvägen 64, S-432 81 Varberg, Sweden (telephone and FAX: +46-35-69248; e-mail: lennart.muller@lthalland.se). 0022-5347/06/1752-0704/0 Vol. 175, 704-708, February 2006 THE JOURNAL OF UROLOGY ® Printed in U.S.A. Copyright © 2006 by AMERICAN UROLOGICAL ASSOCIATION DOI:10.1016/S0022-5347(05)00182-5 704