Ultrasonography reveals a high prevalence of lower spinal dysraphism in children with urogenital anomalies

Abstract

Lower spinal dysraphism is frequently reported in anorectal anomaly combined with urogenital anomalies. The prevalence of the spinal dysraphism has not been comprehensively studied in children with simple urogenital anomalies. We evaluated the prevalence of the spinal dysraphism using ultrasound data of the lumbosacral area in children with urogenital anomalies. Lumbosacral ultrasound images of 259 children who underwent urological surgery with simple urogenital anomalies were reviewed by an ultrasound-specialized radiologist. The primary outcome measures were the conus medullaris (CM) level and the thickness of the filum terminale. The spinal ultrasonographic findings that were assessed in children showed abnormal spinal findings compared with the other children having normal findings. Two years later, the follow-up telephone interviews were made with the parents of the children with abnormal findings. Eighteen children were differentiated as the abnormal finding group. They were suspected of spinal cord tethering. The level of CM was lower, and the filum terminale was thicker compared to the normal group [L2(lower (L)) vs. L1(L), 2.2 mm vs. 0.8 mm]. Of eighteen children, four were confirmed as tethered spinal cord with lipoma on magnetic resonance imaging by the time of surgery, and two were strongly suspected of occult spinal dysraphism (OSD) based on ultrasound findings and follow-up interviews. The prevalence of OSD in children under 24 months of age with simple urogenital anomaly was higher than what was reported for the general population. Ultrasound examination of spinal structures before caudal block in children with urogenital anomaly should be considered.