Development of a standardized method for radiation therapy contouring of the piriform cortex
Shearwood McClelland III and Gordon A. Watson
For medically intractable temporal lobe epilepsy (TLE), Level I evidence has established the superiority of anterior temporal lobectomy (ATL) over either continued medical management alone or stereotactic radiosurgery (SRS) in achieving durable seizure freedom (1-2). Recent work has indicated that the piriform cortex, a structure not included in traditional operative nor radiosurgical volumes, plays a key role in TLE and that inclusion of this structure in operative resection can increase the likelihood of seizure freedom (3). For TLE patients who are not operative candidates, this structure provides a potential SRS target. Presently, there exists no methodology for radiation treatment planning delineation of the piriform cortex.
Keywords: Piriform cortex, medically intractable temporal lobe epilepsy, radiation therapy contouring, stereotactic radiosurgery, linear accelerator, Gamma Knife