The initial PoleStar™ user sites have completed such procedures as craniotomies, transsphenoidal surgeries, and brain biopsies. The number of procedures demonstrates the beginning of the procedural adoption of our technology, and the first clinical results were presented at several scientific meetings and in papers that are published in the Journal of Neurosurgery, Neurosurgery and The Journal of Neurosurgical Anesthesiology. In addition to these studies of PoleStar procedures, additional third party studies have been performed exploring the importance of complete brain tumor resection as well as the benefits of image guided surgery. These studies illustrate the benefits of our technology.

Complete Tumor Resection Increases Survival Rates Resulting in Better Patient Outcomes

• Malignant brain tumor excisions have shown that as much as 80% of surgeries leave part of the tumor behind (Harvard Magazine, Nov-Dec 2000).

• Importance of total resection of tumors of the central nervous system on the prognosis of patient's survival. In a study comparing subtotal vs. partial resection of Glioblastoma multiforma (GBM), the cumulative survival rate doubles (201%) compared to the partial resection group (Kieihues and Cavanee, 2000).

• Another study based on 570 patients by Lacroix and co workers (AANS 1999) showed that the survival rate was 40%-57% higher for patients with gross total removal of tumor compared to patients with subtotal resection, depending on tumor type.

• Another study (Nitta and Sato, 1995) of 101 patients showed that the survival rates for total resection were significantly higher than those for patients who had sub-total or partial resection.

• Similar findings were reported by Ammirati and co workers (1987) with a factor of 2.6 in the survival of glioblastoma and astrocytoma patients who had total resection vs. patients with a subtotal resection.

Image Guided Surgery Reduces Costs

• Length of stay, hospital cost and operative time were reduced by 56%, 35%, and 43% respectively when image guided surgery (IGS) was used as compared to conventional surgical methods. (Bingaman and Barnett, Image Guided Neurosurgery, Quality Medical Publications, 1996).

iMRI Increases the Efficacy and Accuracy of Interventions

The special contribution of intraoperative MRI to the outcome of surgery is described by Knauth and co workers (1999). Out of 41 patients, 22 (53.7%) had intraoperative MR imaging showing residual tumor, after the surgeons believed total resection was achieved. In 17 out of these 22 patients surgery was continued. Early postoperative MR imaging showed no residual tumor in 31 cases (75.6%).