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Minimally Invasive Thumb-sized Pterional Craniotomy for Surgical Clip Ligation of Unruptured Anterior Circulation Aneurysms
Published on: August 11, 2015
Multiscope Technique Combining an Endoscope and Exoscope for Neck Clipping of Cerebral Aneurysms
Junshi Cho1, Takashi Sugawara1, Hiroto Yamaoka1
1Department of Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan.
Objective:
In aneurysm clipping, the use of an endoscope improves the visualization of the anatomic structures around the aneurysm, allowing for improved dissection and clipping techniques. Furthermore, it makes the surgery less invasive. The disadvantage of using the endoscope and microscope together is that the surgeon must move the line of sight significantly between viewing the operative field through the eyepiece of the microscope and viewing the endoscope monitor. This disadvantage makes it difficult for the surgeon to safely insert the endoscope in the optimal position. This study presents a new method for observing the surgical field with a picture-in-picture system using both an endoscope and an exoscope that can overcome the disadvantage of multiscope surgery.
Methods:
The endoscope was used when the anatomic structures around the aneurysm could not be observed with the exoscope only. An image from the endoscopic monitor was inserted into the exoscopic monitor. The surgeon inserted the endoscope in the optimal position while viewing the endoscope monitor and ensured that the structures in the path of the endoscope were not damaged while they viewed the exoscope monitor.
Results:
Three patients underwent aneurysm clipping. The use of an endoscope made the procedure less invasive, and the surgeon was able to safely insert the endoscope in the optimal position. Only slight movement of the line of sight was required to view the 2 monitors.
Conclusions:
The endoscope and exoscope multiscope picture-in-picture system can facilitate safer aneurysm clipping compared with combined microscopic and endoscopic surgery.

