title: Accuracy of direct magnetic resonance imaging-guided placement of drug infusion cannulae.
abstract: An intraoperative MRI (iMRI)-compatible system has been developed for direct placement of convection-enhanced delivery (CED) cannulae using real-time imaging. To establish the precision and feasibility of this technology, the authors analyzed findings in patients who underwent direct iMRI CED cannula placement. Three consecutive patients underwent iMRI-guided placement of CED infusion cannulae (6 cannulae) for treatment of diffuse intrinsic brainstem glioma (2 patients) or Parkinson's disease (1 patient). Convective infusion cannulae were guided to the target using the ClearPoint iMRI-based navigation platform (MRI Interventions, Inc.). Placement accuracy was analyzed. Real-time iMRI during infusion cannula insertion allowed for monitoring of trajectory accuracy during placement. During cannula insertion, no reinsertions or changes due to errors in targeting were necessary. The mean radial error was 1.0 ± 0.5 mm (± SD). There was no correlation between the total length of the planned trajectory and the radial error (Pearson's coefficient: -0.40; p = 0.5). The mean anteroposterior and lateral errors were 0.9 ± 0.5 and 0.3 ± 0.2 mm, respectively. The mean in-plane distance error was 1.0 ± 0.4 mm. The mean tip error (scalar distance between the planned target and actual tip) was 1.9 ± 0.9 mm. There was no correlation between the length of the planned trajectory and any of the measured errors. No complications were associated with cannula placement. Real-time iMRI-based targeting and monitoring of infusion cannula placement is a safe, effective, and accurate technique that should enable more selective perfusion of brain regions.
authors.affiliation: Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland; and.
authors.forename: Prashant
authors.initials: P
authors.lastname: Chittiboina
authors.forename: John D
authors.initials: JD
authors.lastname: Heiss
authors.forename: Russell R
authors.initials: RR
authors.lastname: Lonser
mesh_terms: D000293:Adolescent; D000368:Aged; D001932:Brain Neoplasms / Q000188:drug therapy; D001933:Brain Stem; D002404:Catheterization / Q000379:methods*; D002675:Child, Preschool; D005240:Feasibility Studies; D005260:Female; D005910:Glioma / Q000188:drug therapy; D006801:Humans; D036502:Infusions, Intralesional; D008279:Magnetic Resonance Imaging; D008297:Male; D010300:Parkinson Disease / Q000188:drug therapy
keywords: AAV2-GDNF = adeno-associated virus encoding glial cell line-derived neurotrophic factor; CED = convection-enhanced delivery; DBS = deep brain stimulation; DIPG = diffuse intrinsic pontine glioma; IL13-PE = interleukin-13–Pseudomonas exotoxin; PD = Parkinson's disease; accuracy; brainstem glioma; convection-enhanced delivery; gadolinium; iMRI = intraoperative MRI; magnetic resonance imaging; surgical technique; targeting