High-Resolution Three-Dimensional Computed Tomography for Assessing Complications Related to Intrathecal Drug Delivery.

ABSTRACT

BACKGROUND: The assessment of the functionality of intrathecal drug delivery (IDD) systems remains difficult and time-consuming. Catheter-related problems are still very common, and sometimes difficult to diagnose. OBJECTIVES: The aim of the present study is to investigate the accuracy of high-resolution three-dimensional computed tomography (CT) in order to detect catheter-related pump dysfunction. STUDY DESIGN: An observational, retrospective investigation. SETTING: Academic medical center in Germany. METHODS: We used high-resolution three dimensional (3D) computed tomography with volume rendering technique (VRT) or fluoroscopy and conventional axial-CT to assess IDD-related complications in 51 patients from our institution who had IDD systems implanted for the treatment of chronic pain or spasticity. RESULTS: Twelve patients (23.5%) presented a total of 22 complications. The main type of complication in our series was catheter-related (50%), followed by pump failure, infection, and inappropriate refilling. Fluoroscopy and conventional CT were used in 12 cases. High-resolution 3D CT VRT scan was used in 35 instances with suspected yet unclear complications. Using 3D-CT (VRT) the sensitivity was 58.93% - 100% (CI 95%) and the specificity 87.54% - 100% (CI 95%).The positive predictive value was 58.93% - 100% (CI 95%) and the negative predictive value 87.54% - 100% (CI 95%).Fluoroscopy and axial CT as a combined diagnostic tool had a sensitivity of 8.3% - 91.7% (CI 95%) and a specificity of 62.9% - 100% (CI 95%). The positive predictive value was 19.29% - 100% (CI 95%) and the negative predictive value 44.43% - 96.89% (CI 95%). LIMITATIONS: This study is limited by its observational design and the small number of cases. CONCLUSION: High-resolution 3D CT VRT is a non- invasive method that can identify IDD-related complications with more precision than axial CT and fluoroscopy.