Introduction: Conventional frame-based targeting systems for Stereotactic Laser Amygdalohippocampotomy (SLAH) requires multiple patient transfers between OR and MRI suites, allowing greater susceptibility to error in lesion targeting. Intraoperative MRI (iMRI) targeting systems (Clearpoint®, MRI Interventions) obviate the need for intraoperative transfers, but may be associated with additional costs. We therefore undertook a short-term economic evaluation of laser ablation procedures performed with the iMRI targeting system compared to conventional alternatives.
Methods: 45 patient encounters were reviewed, including the 15 most recent of 3 groups: SLAH cases using the ClearPoint system, SLAH cases using the CRW frame, and open surgery cases. One-way MANOVA determined differences between groups for Total Cost incurred by the hospital. Costs were stratified by category. Significant multivariate effects were defined at alpha=0.05. Bonferroni alpha correction defined significant univariate effects (p<0.0038).
Results: Significant differences were found for Total Costs (F[2,38]=10.48, p=0.0002), OR/Anesthesia Time (F[2,38]=54.90, p<0.0001), Hospitalization and Test Costs (p<0.0001). Differences in Total Cost comparing ClearPoint with CRW (99.62% CI: [-$1,221 , $17,630]), and ClearPoint with Open surgery (-$13,493 , $5,054) were not significantly different. ClearPoint OR/Anesthesia Time costs were $6,165 ($3,604 , $8,826) more than CRW. Hospitalization costs were higher for Open Surgery than ClearPoint or CRW (p<0.0001) which were not significantly different from each other (p=0.675). No differences were found for Medication or Procedure Costs. 43% of CRW patients required additional operations to achieve seizure freedom, versus only 23% among ClearPoint patients.
Conclusions: Relative to open surgery, minimally invasive approaches offer measurable reductions in cost. Total Cost of ClearPoint likely falls between that of the comparators. OR/Anesthesia Time costs account for >75% of the total cost difference, representing a 5 hour difference in procedure length. Additionally, ClearPoint was associated with fewer reoperations. The ClearPoint iMRI targeting system is an economically sound alternative to established targeting methods and open surgery.
Patient Care: This research is the only known economic evaluation of iMRI methods for SLAH, The present work suggests stereotactic methods which are associated with nonsignificant differences in cost relative to conventional methods, and a reduced need for reoperation in order to achieve target outcomes. Additionally, we highlight key areas for further cost reduction and future quality improvement.
Learning Objectives: 1. Recognize the key advantages of iMRI methods in the context of laser ablative procedures
2. Appreciate important differences in the relative economic burden of each of the three surgical approaches discussed
3. Identify key areas for potential cost reduction and future quality improvement
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