Prior to the availability of magnetic resonance imaging (MRI), ultrasonography was the procedure of choice in these children. In the presence of a tethered cord, the conus is very low in the spinal canal and its normal movements are reduced. With the advent of MRI, this has become the procedure of choice. While ultrasonography is an excellent screening procedure, it may require considerable expertise to interpret, and the MRI scan is definitive. It is important to emphasize that myelography (injection of dye into the spinal fluid via a spinal tap and then X-raying of the spinal column) is rarely performed in any of these abnormalities because it rarely supplies additional information in other than under the most unusual circumstances.
All of these children should be evaluated by a pediatric urologist (a specialist in the functioning of the urinary system). Subtle bladder dysfunction is not at all uncommon in these infants and children, and although urodynamics (tests of the bladder's functioning) may be difficult to carry out in the neonate, they may be beneficial in terms of making an assessment as to the pre-operative "baseline." At the least, ultrasound studies of the kidneys and ureters are necessary to be sure that there is no evidence of backup of urine into the kidneys or tubes that drain them into the bladder.
MR or CAT scans of the head and upper neck are required only in rare situations, and the need for such studies is best determined by the treating surgeon.