Benefit of repetitive intrathecal triamcinolone acetonide therapy in predominantly spinal multiple sclerosis: prediction by upper spinal cord atrophy

Intrathecal injection of triamcinolone acetonide (TCA) has been shown to provide substantial benefit in a subset of progressive multiple sclerosis (MS) patients with predominant spinal symptoms. We examined whether atrophy of the upper spinal cord (USC) as measured by MRI can serve as a predictive marker for response to repetitive intrathecal TCA application. Repetitive administration of 40 mg TCA was performed in 31 chronic progressive MS patients up to six times within 3 weeks. Expanded Disability Status Scale (EDSS) and maximum walking distance (WD) were assessed before and after the treatment cycle. Cervical 3D T1-weighted images were acquired on a 1.5T scanner at baseline. Mean cross-sectional area of the USC was determined using a semi-automated volumetry method. Results were compared with a group of 29 healthy controls to group patients into those with and without atrophy. Results show a negative correlation between the degree of USC atrophy and treatment benefit. A higher treatment benefit in patients with little USC atrophy but short initial maximum WD was observed. Absence of USC atrophy as measured on MRI is a predictive marker for intrathecal TCA therapy outcome in progressive MS. Patients with initial poor walking abilities, but only little or no atrophy, benefited most from TCA therapy.