Explanation:
Spina bifida occulta results from incomplete fusion of the posterior vertebral arch during embryological development. Unlike more severe forms of spina bifida, it usually does not involve neural tissue protrusion. Many patients remain asymptomatic and the condition is often discovered incidentally on imaging. Physical signs such as a tuft of hair or dermal sinus may be present. Severe variants may be associated with tethered cord syndrome. Imaging helps confirm the diagnosis and assess associated abnormalities. Reference: McLone DG. "Spina Bifida." Pediatric Neurosurgery, 1994.