Introduction/purpose Minimizing the ischemic damage to the brain after intracranial arterial occlusion is critical in improving the patient's prognosis. Solitaire FR Revascularization Device offers a potential new solution for quick recanalization of the occluded vessels, potentially reducing infarct volume and improving outcome. The purpose of this project is to assess and compare the effect of the Solitaire Device on patients' infarct and hemorrhage volume, as compared to combined IV/IA rtPA therapy in IMS I/II.

Methods The 24-h CT (n=99) and MR images (n=10) from subjects in the retrospective Solitaire Study with ICA-T, M1, or M2 occlusions were made available for analysis. The volume of lesions (infarct + hemorrhage) was measured using volume measurement software. Volumes were compared to similar occlusions treated in the IMS I/II studies (n=89), previously measured in similar fashion. Any parenchymal hematoma (PH) was also separately measured and classified as PH1 or PH2. PH volumes were also compared between Solitaire Study and IMS I/II studies.

Results In the Solitaire study, there were 9 PH1 (8.3%) and 6 PH2 (5.5%). In IMS, there were 12 (13.4%) PH1, and 6 (6.7%) PH2. Results of volume measurements, including subjects with no PH, are summarized in Abstract E-004 table 1.

Conclusion Significant differences in lesion volumes between the Solitaire Study and IMS I/II may indicate a clinical benefit in using Solitaire FR Revascularization Device for recanalization of occluded arteries. Other potential clinical and imaging contributors to volume differences will be analyzed and discussed. Whereas the findings reported are hypothesis generating, more conclusive prospective research is needed for confirming the findings of this preliminary analysis. Similar analysis in the recently-completed prospective, randomized SWIFT Study is planned.

Competing interests A. Javadi: ev3/Covidian. T. Tomsick: ev3, Covidian. J. Carrozzella: ev3/Covidian.