As one of the most common intracranial tumors, pituitary adenomas are second only to gliomas and meningiomas in incidence, accounting for approximately 8%–15% of all intracranial tumors. Although most pituitary adenomas are benign, some patients experience a reappearance of clinical symptoms that had previously resolved after surgery. Follow‑up MRI or CT may reveal tumor regrowth or enlargement of residual tumor, or endocrine testing may show that previously decreased hormone levels have risen again—this is clinically defined as pituitary adenoma recurrence. Postoperative recurrence has long been a challenging issue in neurosurgery. Once recurrence occurs, repeat surgery is often more difficult than the initial procedure, and simply relying on conventional equipment to assist resection has limited efficacy. 

Currently, neuroendoscopic transsphenoidal surgery is the predominant surgical approach for pituitary adenomas. This technique overcomes the complications commonly associated with traditional microscopic transsphenoidal surgery, such as extensive trauma, nasal septal perforation, nasal infection, and mucosal atrophy. It offers advantages including less invasiveness, clearer visualization, a wider exposure range, close observation of the lesion, and more precise and meticulous surgical manipulation. These features greatly reduce surgical injury and complications, improve surgical outcomes, and result in less postoperative pain, shorter hospital stays, and lower costs. High‑definition neuroendoscope‑assisted transsphenoidal resection of pituitary adenomas and other intracranial tumors has become a state‑of‑the‑art and appropriate typical procedure under this major trend. 

Since its first clinical application reported by Black's group at Harvard University in 1996, intraoperative MRI (iMRI) has been widely used in the resection of intracranial space‑occupying lesions, functional neurosurgery, and stereotactic biopsy. Its advantages include real‑time intraoperative imaging, timely correction of intraoperative brain shift errors, and precise guidance for surgical and puncture procedures. iMRI offers unique benefits over conventional image guidance in neurosurgery, particularly in the resection of gliomas in eloquent brain areas, removal of invasive pituitary adenomas, real‑time guidance, and precise localization for biopsy. It not only minimizes postoperative tumor residual but also maximally preserves important functional brain areas such as language and motor centers; enables minimally invasive resection of pituitary adenomas and gliomas; reduces the recurrence rate of high‑grade gliomas; appropriately decreases injury to functional nerves adjacent to the tumor, thereby lowering both short‑ and long‑term disability rates; and makes puncture and surgical targets visible, thus enhancing procedural accuracy. 

The contemporary concept of minimally invasive neurosurgery is to maximize lesion removal while minimizing damage to neurological function. The "fish‑eye view" of the neuroendoscope overcomes the blind‑spot limitation of microscopic transsphenoidal pituitary adenoma resection. Compared with microsurgery, the endoscopic approach increases the safety and likelihood of gross‑total tumor resection. However, the learning curve for neuroendoscopic techniques is steep, requiring rigorous training to achieve proficiency intraoperatively. Through standardized training in neuroendoscopic techniques, surgeons can improve the gross‑total resection rate of pituitary adenomas.

Neuronavigation systems can accurately track and localize lesions during surgery, allowing the procedure to be performed under navigational guidance. Due to differences in technical experience and tumor invasion of the cavernous sinus, residual tumor after transsphenoidal surgery is relatively common. By incorporating intraoperative neuronavigation, the surgeon can open the sellar floor and define the surgical field based on the tumor's location, making intraoperative localization more precise and enabling safe and accurate resection of tumor tissue. Nevertheless, neuronavigation has certain limitations. First, significant intraoperative brain shift may occur, causing navigation based on preoperative data to deviate severely, making it impossible to judge relevant structures and even leading to misguidance. Second, many factors can reduce the accuracy of the navigation system, such as changes in the patient's head position relative to the surgical table during surgery, which may introduce obvious errors. Intraoperative X‑ray, tumor ultrasound, and CT have also been used in transsphenoidal pituitary surgery, but their widespread adoption has been hindered by poor resolution, unclear imaging, and radiation exposure.