Navigator system-assisted endoscopic fenestration of a symptomatic cyst in the septum pellucidum--technique and cases report.

Expanding cysts of the septum pellucidum are rare and frequently manifest as intermittent headaches. Although the technique of endoscopic fenestration has been used since 1999, only a limited number of cases have been reported. We have added the use of a navigator system to guide keyhole creation and endoscopic access. To provide experience in navigator endoscopic treatment of symptomatic cyst of septum pellucidum and long-term follow-up of the surgical result. Under the guidance of the navigator system, a burr hole was made and rigid endoscope was inserted into the lateral ventricle through a working sheath. With direct visualization, only one side of the lateral wall of the cyst was fenestrated. And a grasping basket was used to further dilate the perforated hole. Patient A, a 14-year-old male adolescent, had an acute onset of severe headache with increased intracranial pressure. Patient B was a 37-year-old woman with a diagnosis of medically intractable migraine. Both patients experienced dramatic symptomatic relief after surgery at 4.5- and 2-year follow-up exams, respectively. The technique of navigator-assisted endoscopic fenestration in the treatment of a symptomatic cyst of the septum pellucidum might be a safe and effective method. It achieved satisfactory results in our two patients.