Prevalence of the Chiari/Hydrosyringomyelia Complex in Adults with Spina Bifida: Preliminary Results

Abstract

Aim: To establish the prevalence of Chiari malformations and hydrocephalus (HS) in adults with spina bifida (SB).
Introduction: Adults with SB have recently been shown to be at risk from significant deterioration arising from the C/HS complex. Little is known about the prevalence of these malformations in adulthood, their natural history, risk factors for deterioration and optimum management.
Materials and Methods: Patients are recruited from a clinic for adults with SB and hydrocephalus, routinely questioned about recent changes in neurological symptoms and a full neurological examination performed. Functional assessments include: Barthel Index; Nottingham EADL; Nine Hole Peg Test; 10 metre timed walk test. Sagittal T₁ and TSE (turbo spin-echo) magnetic resonance images (MRI) of the cranio-cervical junction and spinal cord are obtained using a 1.0-T MRI system with a phased-array surface coil. Scans are reported blindly.
Results: 76 patients have been assessed, 40 female, 36 male, mean age 27.5 years. Of these, 48 (63.2%) have symptoms±signs compatible with C/HS, but only 18 (23.7%) have reported new, potentially relevant, neurological symptoms over the previous 12 months. Of 25 patients undergoing MRI so far, 19 (76%) have had Chiari malformations and 12 (48%) have had HS. None of those with a negative scan have had signs/symptoms suggestive of the C/HS complex but a negative clinical evaluation has been unable to exclude such pathology.
Conclusions: These early results suggest that the prevalence of the C/HS complex is high in adults with SB and cannot be predicted by neurological examination alone. Given past experience, the need for continued neurological follow up in a large proportion of the SB population throughout adulthood is likely to be essential.

Key words

Chiari - Hydromyelia - Hydrocephalus - Spina bifida