Investigating the application of diving endoscopic technique in determining the extent of pituitary adenoma resection via the trans-nasal-sphenoidal approach.

The aim of the present study was to investigate the advantages and disadvantages of the diving endoscopic technique in pituitary adenoma surgery, and the application value in determining the extent of tumor resection. A total of 37 patients with pituitary adenoma initially underwent tumor resection under an endoscope-assisted microscope via standard trans-nasal-sphenoidal approach, and tumor cavity structure was observed by applying the diving endoscopic technique. Surgery was subsequently performed again under a microscope or endoscope. The diving endoscopic technique allowed surgeons to directly observe the structure inside a tumor cavity in high-definition. In the present study, 24 patients had pituitary macroadenomas or microadenomas that did not invade the cavernous sinus, and were considered to have undergone successful total resection. Among these patients, no tumor residues were observed through the diving endoscopic technique. Some white lichenoid or fibrous cord-like tissues in the tumor cavity were considered to be remnants of tumors. However, pathology confirmed that these were not tumor tissues. For tumors that invaded the cavernous sinus in 13 patients, observation could only be conducted under the angulation endoscope of the diving endoscope; i.e., the operation could not be conducted under an endoscope. The present study suggests that the diving endoscopic technique may be used to directly observe the resection extent of tumors within the tumor cavity, especially the structure of the tumor cavity inside the sella turcica. The present study also directly validates the reliability of pituitary adenoma resection under endoscope-assisted microscope. In addition, the diving endoscopic technique also allows the surgeon to observe the underwater environment within the sella turcica.