Thanks for your reply. While I am no expert on the mechanics of the surgery, I assumed more than one endoscope was used in my surgery due to the tumor's large size. My tumor extended from the IAC ( Internal Auditory Canal ) across the space to exert a mass effect on my brain stem and cerebellum. Using an endoscope to visualize the tumor toward the brain would require a certain angled endoscope and looking toward the IAC would need a different angled one.
As far as elaborating further, the tumor was debulked and then dissected from the brain stem, cerebellum, and the V, VII, and Xth cranial nerves. The facial nerve ( VII ), which is normally cylindrical, was compressed by the tumor to the width of a sheet of paper, but so far only affects my tongue which was numb before surgery anyway, and dissection was successful. As mentioned above, the dissection from the Trigeminal and Vagus nerves was more difficult and resulted in some facial numbness around the corner of my mouth and right chin, and the already mentioned
vocal cord and swallowing problems. I'll add I still have some episodes of disequilibrium when outdoors or in large buildings like stores.
Sorry I cannot be more specific on the mechanics, but I was focused on the experience of the surgeon with his technique, and the facts of shorter operation time, shorter recovery time, lower morbidity than open craniectomies, and less hospital time. Hope this helps. Feel free to ask more questions if you want, maybe I will have answers.