Inventor of Radiosurgery System Puts it to the Test

April 23, 2010 - Professor Lars Leksell, the inventor of the Gamma Knife, a radiosurgical instrument, performed the world's first Gamma Knife surgery at nearby Sophiahemmet Hospital, the location of the first Leksell Gamma Knife.

Karolinska University Hospital recently acquired Elekta's fifth generation radiosurgery system, Leksell Gamma Knife Perfexion. Since January, Karolinska clinicians have been using the system to treat more patients per day and tumors that used to be hard to reach. Physicians also are much more easily treating multiple metastases in a single session.

While the clinicians are currently treating traditional Gamma Knife indications, such as metastases, meningiomas, arteriovenous malformations, dural fistulas, acoustic neuromas, the immediate impact Perfexion has made is the ease with which physicians can treat two or more metastases in one session.

"We treat five to 10 metastases on a regular basis, because the automated collimator makes it possible to rapidly plan and treat multiple tumor isocenters," Karolinska neurosurgeon Ernest Dodoo explained. "Suddenly, it is feasible to treat everything we see. Now, the question is if it makes sense clinically from a therapy standpoint."

Leksell Gamma Knife Perfexion replaced two earlier generation Leksell Gamma Knife 4C systems, one at Sophiahemmet Hospital and the other at Karolinska University Hospital. Each had been treating about 250 patients per year for the last three years.

On Jan. 11, Karolinska used Leksell Gamma Knife Perfexion to treat its first case, a patient with a glioblastoma. Since then, Karolinska has treated 120 patients with Perfexion and this single system already rivals the daily patient volume of the previous systems by virtue of its unique features.

"We treated five patients in one day last week, including two quite complex cases," Dr. Dodoo recalled. "With either of our previous systems that would have been logistically difficult. With Perfexion, up to five patients per day is absolutely realistic."

In addition to the system's automated collimator, the enhanced planning system for Leksell Gamma Knife Perfexion also is boosting the efficiency of Karolinska's radiosurgery practice.

"Planning is a lot easier, more intuitive and very user friendly," Dr. Dodoo noted. "We can visualize the isodose lines simultaneously as we trace them and the dynamic shaping makes dose planning much simpler. It really has changed our approach."