Radiosurgery Equipment Malfunctions in U.S., France
by Barbara Kram, Editor | June 18, 2007
The Cleveland Clinic
has discontinued use of its
BrainLAB equipment
(click to enlarge)
has discontinued use of its
BrainLAB equipment
(click to enlarge)
BrainLAB AG of Munich, Germany, makers of Novalis targeted radiotherapy equipment and guidance software, has warned of malfunctioning machines in France and the U.S.
The company's public announcement on June 15, 2007 indicates that the problem is the result of an incompatibility between the BrainLAB's positioning software and another company's -- Leksell's -- headrings, which hold the patient in place during neurosurgery.
The problem results in a 1.25mm shift in target area alignment during radiosurgery, which gains its efficacy from the precision accuracy by which tumor cells are destroyed by radiation while sparing surrounding healthy tissue.
The BrainLAB says that two U.S. hospitals and four in France use the incompatible hardware/software configuration that results in the misguided radiation. "This alignment shift falls within accepted safety margins and known deviations published in the field of radiosurgery and for this reason was not discovered earlier during routine product test and customer commissioning procedures," BrainLAB said.
However, a prior notice to hospitals on June 4 indicated that the malfunction "may cause serious injury or death to the patient," AP reports. Hundreds of patients in France may be impacted. The U.S. facilities affected are the Cleveland Clinic in Ohio and Valley Medical Center, Renton, Washington. Both facilities discontinued using BrainLAB machines. France's Health Ministry has also suspended use of BrainLAB equipment.
The specific problem configuration occurs when BrainLAB's Novalis radiosurgery device is used with a specific configuration of BrainLAB Target Positioner version 40700-3A for Leksell headrings. Centers offering radiosurgery treatments without this specific configuration do not experience this shift in target area alignment.
How radiosurgery works
In radiosurgery, a high-energy beam of radiation is focused on a target area from various angles. During treatment, the radiation delivery device moves around the patient so that the beam penetrates the target area from different angles, avoiding vital structures.
Where the beams intersect, a higher-concentration of the radiation dose is created that is strong enough to effectively treat tumors. While the target area receives the full dose of radiation, the surrounding area receives a lesser dose, reducing the effect on normal tissue.
The shape of the tumor determines the target area, which in turn decides the diameter of the radiation beam. For effective treatment, the target area must be large enough to encompass the entire tumor. A safety margin around the tumor is included in calculations to ensure that no portion of the tumor falls outside of the target area.
In cranial radiosurgery, a headring is first securely fastened to the head of the patient and then a series of CT scans is acquired. A treatment plan is created using the CT scans, determining the optimal delivery of radiation for the patient. The patient is then placed into position for treatment.
It is during patient positioning that the shift in target area alignment occurred. The alignment of the radiation beam shifted from the intended target area, but remained within the safety margin, according to a BrainLAB statement.
The company's public announcement on June 15, 2007 indicates that the problem is the result of an incompatibility between the BrainLAB's positioning software and another company's -- Leksell's -- headrings, which hold the patient in place during neurosurgery.
The problem results in a 1.25mm shift in target area alignment during radiosurgery, which gains its efficacy from the precision accuracy by which tumor cells are destroyed by radiation while sparing surrounding healthy tissue.
The BrainLAB says that two U.S. hospitals and four in France use the incompatible hardware/software configuration that results in the misguided radiation. "This alignment shift falls within accepted safety margins and known deviations published in the field of radiosurgery and for this reason was not discovered earlier during routine product test and customer commissioning procedures," BrainLAB said.
However, a prior notice to hospitals on June 4 indicated that the malfunction "may cause serious injury or death to the patient," AP reports. Hundreds of patients in France may be impacted. The U.S. facilities affected are the Cleveland Clinic in Ohio and Valley Medical Center, Renton, Washington. Both facilities discontinued using BrainLAB machines. France's Health Ministry has also suspended use of BrainLAB equipment.
The specific problem configuration occurs when BrainLAB's Novalis radiosurgery device is used with a specific configuration of BrainLAB Target Positioner version 40700-3A for Leksell headrings. Centers offering radiosurgery treatments without this specific configuration do not experience this shift in target area alignment.
How radiosurgery works
In radiosurgery, a high-energy beam of radiation is focused on a target area from various angles. During treatment, the radiation delivery device moves around the patient so that the beam penetrates the target area from different angles, avoiding vital structures.
Where the beams intersect, a higher-concentration of the radiation dose is created that is strong enough to effectively treat tumors. While the target area receives the full dose of radiation, the surrounding area receives a lesser dose, reducing the effect on normal tissue.
The shape of the tumor determines the target area, which in turn decides the diameter of the radiation beam. For effective treatment, the target area must be large enough to encompass the entire tumor. A safety margin around the tumor is included in calculations to ensure that no portion of the tumor falls outside of the target area.
In cranial radiosurgery, a headring is first securely fastened to the head of the patient and then a series of CT scans is acquired. A treatment plan is created using the CT scans, determining the optimal delivery of radiation for the patient. The patient is then placed into position for treatment.
It is during patient positioning that the shift in target area alignment occurred. The alignment of the radiation beam shifted from the intended target area, but remained within the safety margin, according to a BrainLAB statement.
