To investigate the value of ultrasound in tethered cord syndrome (TCS) in infants.

From December 2005 to July 2013, 25 cases TCS were confirmed by surgery in Shenzhen children＇s hospital. The ultrasonogram and MRI of 25 infants were analysed retrospectively. The diagnostic accuracy of ultrasound and its clinical significance were evaluated.

In 25 cases of TCS confirmed by surgery, the coincidence rate of conus level detected by ultrasound [96% (23/24)] was lower than that by MRI (100%(25/25)). Ultrasound showed reduced spinal cord vibration in 4 cases, disappeared spinal cord vibration in 21 cases. Two cases of reduced spinal cord vibration detected by ultrasound were confirmed as disappeared spinal cord vibration by surgery. The coincidence rate of disappeared spinal cord vibration detected by ultrasound was 91% (21/23). The sacral spinal segments form showed by ultrasound were entirely consistent with those of MRI, including 4 cases of enlarged spinal cord, 13 cases of spinal cord without enlargement and 8 cases of spinal cord ended with rat caudate. Twenty-five cases of TCS had malformations: 7 cases meningocele (3 cases combined lipoma), 14 cases myelomeningocele (5 cases combined lipoma, 1 case combined hydromyelia), 3 cases spinal canal-epidermis fistula (all combined lipoma) and 1 case solitary lipoma. Compared with the operation findings, ultrasound misdiagnosed 2 cases of myelomeningocele as meningocele, missed 1 of case lipoma which combined with meningocele. MRI missed two cases of spinal canal-epidermis fistula.

Infantile spinal ultrasound examination can accurately locate the position of conus, accurately display the spinal cord. Compared with MRI, ultrasound examination can real-time visually display spinal cord vibration and help to diagnose tethered cord. Ultrasound examination are convenient, repeatable operation with low cost, therefore it can be used as the preferred screening method to diagnose of tethered spinal cord.