[Abstract] Objective To summarize the various methods of microsurgery for saddle area tumors, the treatment effects, analyze the causes of postoperative complications, and discuss preventive measures. Methods A retrospective analysis of 206 cases of giant pituitary adenoma, 28 cases of saddle node meningioma and 36 cases of craniopharyngioma diagnosed by CT, MRI and endocrine examination from 1981-12 to 2001-12. In group B, 97 cases were resected simply through the nasal vestibule – nasal septum – pterygoid sinus or through the single nostril – pterygoid sinus (hereinafter referred to as “transnasal butterfly”), and in group C, 26 cases were resected by combining the above two methods in stages and stages. In group C, 26 tumors were resected by combining the above two methods in a staged and staged manner. In group D, all tumors were resected by craniotomy through the pterygoid approach. Results: 42 cases (50.6%), 21 cases (21.6%), 24 cases (92.3%), and 50 cases (92.7%) in groups A, B, C, and D, respectively, with total or subtotal resection; 2 cases (2.4%), 1 case (1.03%), and 0, 0 in the four groups with death; 51 cases (61.4%), 18 cases (18.6%), and 11 cases (42.3%) in the four groups with uveitis, respectively. In the four groups of hypothalamic damage, there were 26 cases (31.3%), 2 cases (2.1%), 0, 0; in the four groups of cerebrospinal fluid nasal leakage, there were 0, 27 cases (27.8%), 8 cases (30.8%), 0. The rates of total incision and urinary collapse in the four groups were compared by chi-square test, and the difference was very significant at P < 0.01. . Conclusion Under the condition of strict control of the indications for transsphenoidal and transsphenoidal approaches, the staged and staged resection of giant pituitary adenoma is a safe and effective treatment method to improve the total resection rate, reduce the mortality and recurrence rate, and decrease the complications by taking the advantages of each of them. Xiong Hui, Department of Neurosurgery, Affiliated Hospital of Shandong University of Traditional Chinese Medicine Pituitary adenoma is a common benign tumor with a general population incidence of 1/100,000, accounting for about 10% of intracranial tumors [1], and is the most common tumor in the saddle area. The surgical mortality rate of pituitary tumors is generally around 2% [2], but the surgical mortality rate of giant pituitary adenomas is still not less than 18% [3]. From 1981-12 to 2000-12, we admitted 744 cases of pituitary tumor, 206 cases of pituitary macroadenoma (27.69%), 54 cases of saddle node meningioma and craniopharyngioma, which were treated by different ways of microsurgery and achieved satisfactory results, which are summarized and discussed in terms of surgical principles, operation and prevention of complications. 1 Clinical data 1.1 General data 114 male cases and 146 female cases, age 12-76 years old, average 38.6 years old. The duration of the disease ranged from 1 to 18 years, with an average of 7.2 years. All cases were confirmed by pathological section examination. The endocrine examination types of pituitary macroadenoma were: 97 cases (47.1%) of non-functional adenoma; 109 cases (52.9%) of functional adenoma, including 36 cases of growth hormone adenoma, 43 cases of prolactin adenoma, 14 cases of adrenocorticotropic hormone adenoma and 16 cases of untyped adenoma; 28 cases of meningioma and 36 cases of craniopharyngioma. 1.2 Main clinical manifestations The course of the disease was mostly slow. 57 cases showed headache, 43 cases showed amenorrhea and lactation, 84 cases showed hypogonadism, 33 cases showed growth retardation, 19 cases showed polyuria, and 150 cases showed visual impairment and visual field defects. 21 cases showed tumor stroke. 1.3 Imaging examination All 260 cases were examined by cranial X-ray, CT and MRI. CT coronal scan could show the size of the tumor and its extension to the superior, inferior and parasternal saddles, the degree of pneumatization of the pterygoid sinus and the destruction of the saddle base, while MRI could show the tumor shape and its relationship with the surrounding structures more clearly. In 12 cases, the tumors protruded into the three ventricles and combined with hydrocephalus. 2 Treatment methods 2.1 Case selection and grouping: All 206 cases belonged to grade 4 or 5 of Hardy's pituitary adenoma grading standard [4], and also met the criteria proposed by Grote that tumors with a maximum diameter of more than 40 mm are considered giant [5]. 206 cases were randomly divided into three types of surgery: 83 cases in group A, microsurgical resection of the tumor through the pterygoid approach alone; 97 cases in group B, microsurgical resection of the tumor through the nasopalatine approach alone; group C, microsurgical resection of the tumor through the nasopalatine approach. In group C, there were 26 cases, among which 15 cases were operated through pterygoid approach first, and the tumor was partially or mostly resected, and then the tumor was partially or mostly resected through nasopterygoid approach about 3 months later; the other 11 cases were operated through nasopterygoid approach first, and then the tumor was partially or mostly resected through pterygoid approach about 3 months later, depending on the situation. 2.2 Preoperative medication and anesthesia: Patients were given prednisone 5mg orally 3 days before surgery, 3 times a day. Intraoperatively, 200 mg of hydrocortisone was administered intravenously, and endotracheal intubation and general anesthesia were used for anesthesia. 2.3 Surgical approach and method: The main points of operation for microsurgical resection of tumor through the pterygoid approach were: (1) The patient was lying flat, with the head fixed in a head frame, above the chest, rotated 300 left and tilted back about 100, so that the frontal zygomatic process was in the middle of the operative field and at the highest point. (2) The bone window should reveal the frontal and temporal poles, bite off the pterygoid crest, and make the edge of the frontal bone window flush with the base of the anterior cranial recess, and special attention should be paid to the treatment of the middle meningeal artery and orbital meningeal artery. The main points of microsurgical resection of tumor through the nasopalatine approach are as follows: (1) The patient is lying down with the head tilted back and the chin-occipital line is perpendicular to the plane of the operating table. (2) Make a curved incision at the junction of skin and mucosa at the left side of the anterior nasal septum, starting from the top of the anterior nasal septum to the bottom of the nasal septum, and make a horizontal incision at the bottom of the nasal threshold of the curved incision toward the base of the nasal columella, reaching the upper end of the external human middle of the anterior nostril, paying attention not to cut through to the contralateral nasal vestibule. (3) Separate the mucous cartilage membrane of the left side of the nasal septum to reach the vertical plate of the sieve bone, dislocate the cartilage from the vertical plate and then separate the periosteum on both sides of the vertical plate to reach the anterior wall of the pterygoid sinus. (4) Enter along the submucous cartilage membrane of the nasal septum, insert Hardy dilators on both sides of the sieve vertical plate, bite off the sieve vertical plate, open the anterior wall of the pterygoid sinus with the midpoint of the line connecting the opening of the pterygoid sinus as the center, push the mucosa of the pterygoid sinus to the lateral wall or peel it off, open the saddle base strictly according to the midline, and open the saddle base after x-ray positioning if necessary. (5) After cauterizing the dura with bipolar electrocoagulation, if there is no active bleeding from the puncture, a "ten" shaped incision can be made. The methods to achieve complete resection of tumor through nasal butterfly approach are: (1) the middle and lower part of tumor should be resected first, and the upper part should be resected later, so as to avoid premature saddle septum descent, which will affect the complete resection; (2) if most of the tumor is resected, but the saddle septum is not descent, bilateral jugular veins can be compressed and anesthesia can be controlled, so that the intracranial pressure can be increased transiently or the lumbar subarachnoid catheter can be slowly injected with filtered air or saline or Ringer's lactate solution 5~30ml to make the ICP uniform. ~30 ml to increase ICP uniformly and consistently, forcing the suprasellar tumor to descend into the operative field [4]. 2.4 Postoperative management: pay close attention to keep the airway unobstructed, observe the changes of consciousness, pupils and vital signs, record the in and out volume, routinely use antibiotics for 7 days, hormone replacement therapy for 3-5 days, remove the nasal stuffing after 3 days, and remove the stitches on the 7th day of the wound. Patients with non-total resection of tumor are required to receive radiation therapy at a dose of 30-40GY/3-4 weeks or oral bromocriptine treatment at a dose of 7.5mg 3 times daily. Postoperatively, the patient should be reviewed at 3 months, 6 months and 1 year, and then every 2 years until 10 years after surgery. The urinary collapse was cured in 1~6 weeks with oral diphacitracin or mydriasis in mild cases and injection of posterior pituitary hormone or long-acting urinary collapse stop in severe cases, while the CSF leak was cured in about 3 weeks with head high position and multiple lumbar punctures to release fluid. In group A, there were 42 cases (50.6%) of total or subtotal resection and 2 cases of death, all of which were caused by hypothalamic injury in the early stage of microsurgery via pterygoid approach; 51 cases (61.4%) of urinary collapse, 26 cases (31.3%) of hypothalamic damage, and no CSF leakage. 21 cases (21.6%0) of total or subtotal resection and 1 case of death in group B were caused by hemorrhage in the tumor cavity and pituitary stalk injury in the early stage of microsurgery via nasal butterfly approach. In group C, there were 24 cases (92.3%) of total or subtotal resection, 11 cases (42.3%) of urinary collapse, 8 cases (30.8%) of CSF leakage, and no surgical death or hypothalamic damage; in group D, there were 50 cases (92.7%) of total or subtotal resection and 10 cases (18.8%) of CSF leakage. In group D, there were 50 cases (92.7%) with complete or subtotal excision, 10 cases (18.9%) with uroemesis, and 8 cases (30.8%) without CSF leakage, surgical death or hypothalamic damage. There were no CSF leakage, surgical death or hypothalamic damage. The rates of total excision and uroemesis in the four groups were compared, and all of them were significantly different by chi-square test at P<0.01. 5 Discussion 5.1 Diagnostic criteria of pituitary giant adenoma The surgical efficacy of pituitary adenoma is closely related to the tumor size, so it is important to unify the diagnostic criteria of each type in treatment. According to Hardy's grading criteria [4], those with grade 4 and 5 are considered giant adenoma, and also conform to Grote's proposal that tumors with a maximum diameter of more than 40 mm are considered giant [5]. 206 cases in this group used the above criteria, and the suprasellar, intra-sellar and extension to the pterygoid sinus of the tumor were included in the measurement. In this paper, 109 cases of pituitary giant adenoma, 28 cases of saddle node meningioma and 36 cases of craniopharyngioma adopted the trans-pterygoid approach and achieved good results. In clinical practice, we found that this approach has the following advantages: (1) The distance from the bone window to the anterior bed projection is the shortest route among all saddle surgery approaches, and the angle of view is the largest, which can make full use of the natural anatomical gap of the brain. (1) The distance from the bone window to the anterior bed projection is the shortest route among all saddle surgery approaches, and the angle of view is the largest. (2) With microsurgery, the important structures in the saddle area, such as the optic nerve, optic cross, internal carotid artery and all penetrating branches, can be protected under direct vision. (3) This approach can make full use of the four anatomical gaps in the saddle area [6] to maximize the resection of the tumor, and intraoperative residuals are not likely to occur. However, this approach has the following disadvantages: (1) it is more traumatic and takes longer time, and is not suitable for elderly and frail patients; (2) it cannot be used for anterior optic crossing; (3) it cannot be completely resected for tumor protruding into the three ventricles, and it is easy to damage the hypothalamus, optic nerve, important branches of internal carotid artery, cavernous sinus and cranial nerves in them, causing serious complications. 5.3 Advantages and disadvantages of transsphenoidal surgery for pituitary macroadenoma Transsphenoidal surgery has been practiced and developed for more than 80 years and has accumulated rich experience, which has perfected this treatment technique and improved the surgical results significantly and reduced the risks [7]. There is no surgical death. The advantages include: (1) less trauma and shorter operation time; (2) faster postoperative recovery and fewer complications; (3) no craniotomy and blood transfusion; and reduced cost. The disadvantages are: (1) some tumors cannot be removed, such as: the tumor extends to the saddle in a dumbbell shape; imaging examination suggests that the tumor is hard and rich in blood flow; most of the tumor resides in the saddle in an inverted gourd shape; (2) the field of view is small and the path is deeper; (3) special instruments are needed, such as transsphenoidal surgical instruments, surgical microscope or deep cold light source and high-speed miniature grinding drill, X-ray monitoring device, etc. 5.4 Prevention and control measures of complications The most common complication after pituitary giant adenoma surgery is uveitis, which occurred in 80 cases accounting for 38.8% of the 206 cases in this paper, followed by CSF leakage, hypothalamic injury, optic nerve injury, cavernous sinus injury, and intracranial hematoma, the latter three of which did not occur in any of the 206 cases in this paper. Preventive and curative measures are: 1. When entering through the pterygoid point: (1) familiar with the microscopic anatomy of the saddle area. (2) careful intraoperative identification and protection of the pituitary stalk and its blood supply arteries; (3) no release of the optic nerve and optic cross without intracapsular resection of the tumor [8]; (4) electrocautery as close as possible to the tumor wall and cutting off the de novo blood supply vessels of the optic nerve and optic cross to the tumor; (5) for the de novo blood supply arteries of the surrounding squeezed vessels, especially when dealing with the intracranial arterial vessels in the saddle, the the tumor end (distal end) and then the proximal end [9]. (6) Use the arachnoid interface to detach and remove the tumor envelope, which can completely remove the tumor without damaging the surrounding structures. (7) When separating along the arachnoid interface, it is important to carefully identify and distinguish the small arteries supplying the tumor from the hypothalamic penetrating arteries that travel on the surface of the tumor to avoid accidental injury. (8) At the end of surgery, cover the large vessels of Willis ring with 3% poppyine cotton tablets and apply Nimiton to prevent vasospasm after surgery. (9) Strictly grasp the indications and contraindications for microsurgery via pterygoid approach. 2. Even in the optic nerve or internal carotid artery bulge, there are also septum and coronal septum [10]; (3) the depth of puncture before cutting saddle base dura is ≤1.0 cm, the blade of cutting dura should be sharp, and the tumor should be resected in saddle block first, and the operation should be gentle to avoid pulling and injuring the pituitary stalk; (4) the saddle septum drops after tumor resection, at this time there is CSF overflow, and saddle base repair should be performed to prevent postoperative CSF nasal leakage; ( (5) For those with poor pneumatization of the pterygoid sinus, a high-speed micro-grinding drill can be used to open the "A-mediated" pterygoid sinus into the saddle base under X-ray surveillance in order to remove the tumor [11]. (6) The operation must be performed with sophisticated instruments. Because the transsphenoidal approach and the transnasal pterygoid approach have their own advantages and disadvantages, our group C adopted the two methods to remove the tumor in stages, so that the two methods can complement each other's strengths and weaknesses, which obviously improved the total resection rate and reduced complications and mortality. Reference literature (omitted)