What Is Laser Ablation’s Role in Treating Hippocampal Epilepsy?

Laser ablation appears to entail less perioperative morbidity, which means that it may be suitable for older patients and those with medical comorbidity.

Of 95 patients who received selective laser ablation of the hippocampus and amygdala at the University of Washington and Emory University, there were six complications, yielding a complication rate of 6.3%. There is a small risk that insertion of the probe, and the ablation itself might produce vascular injury, which could result in cerebral infarct or hemorrhage. Most complications were transient, except for one patient who had a persistent visual field deficit in the upper quadrant. However, visual field deficits are an expected outcome in many patients who receive anterior temporal lobectomy, said Dr. Miller.

Not all case series report complication rates, and others report complications inconsistently. The most complete information on complications comes from randomized controlled trials. In one such trial published in 2001, Wiebe et al reported a 10% complication rate with standard surgery to treat temporal lobe epilepsy, including two patients who had verbal memory declines at one year that interfered with their employment, said Dr. Miller.

In addition, laser ablation requires shorter hospitalization, and patients still may undergo additional surgery if laser ablation does not effectively treat their seizures.

Further studies are needed to confirm these initial findings. Dr. Miller said that patients likely would not agree to participate in a randomized controlled study comparing anterior temporal lobectomy with selective laser ablation because most patients choose to have laser ablation over anterior temporal lobectomy. A randomized trial of laser ablation versus medical management might be feasible, however, and would provide useful data, he concluded.

—Jake Remaly