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.

Advances in drug delivery to high grade gliomas

“…Randomized trials of CED therapy have not yet shown so far survival advantages as compared with standard of care. An intraoperative magnetic resonance imaging (MRI)-compatible system has been developed for direct placement of CED cannulae using real-time imaging ( Figure 1A) (15). In particular, catheter design and placement-in are critical components of any CED protocol (34).…”

“…However, early studies may have been limited by "first generation" delivery techniques and recently reported improvements may potentially allow for better outcomes (26). Coupled with computational methods allowing a better determination of the biodistribution of the infusate (34), the above cannula insertion procedures may improve the thoroughness of CED for HGG treatment (15). An intraoperative magnetic resonance imaging (MRI)-compatible system has been developed for direct placement of CED cannulae using real-time imaging ( Figure 1A) (15).…”

“…Healthy mice were infused by CED with KU60019 and the drug kinetics followed by HPLC/MS on extracts of different brain regions. 15, with permission. Twenty-four hour later, no drug could be detected all over the brain or in other organs, indicating rapid draining and excretion.…”

“…In particular, catheter design and placement-in are critical components of any CED protocol (34). An intraoperative magnetic resonance imaging (MRI)-compatible system has been developed for direct placement of CED cannulae using real-time imaging ( Figure 1A) (15). Patients underwent intraoperative MRI-guided placement of six CED infusion cannulae each, for treatment of diffuse intrinsic brainstem glioma or Parkinson's disease.…”

Real-time magnetic resonance imaging-guided frameless stereotactic brain biopsy: technical note

“…3,4,8 To overcome these limitations, technology has been developed that now permits the integration of intraoperative MRI (iMRI) with frameless stereotaxy. The resolution and real-time feedback of this iMRI technology has been demonstrated in phantom experiments, 12,18 nonhuman primate studies, 16,17 drug infusion cannula placement, 2 and placement of deep brain stimulator leads. 9,11,20,21 Application of this technology to stereotactic brain biopsy could eliminate misdiagnosis secondary to faulty targeting, provide realtime adaptability for needle trajectory, confirm accurate biopsy cannula position, and provide immediate imaging of complications.…”