To investigate the surgical treatment of cranial benign nasal and sinus tumors. Methods 6 cases of benign nasal cavity and sinus tumors invading into the skull base were reported, including 3 cases of ossifying fibroma, 1 case of osteoma, 1 case of osteochondroma, 1 case of osteoblastoma (grade I-II), and 1 case of giant cell tumor (grade I-II) of bone, all of them were resected by 1-side maxillary lifting and restoration and combined craniofacial approach, with total resection of the tumors in 4 cases, and subtotal resection of the tumors in 2 cases. Results There were no surgical complications, postoperative follow-up for 2-3 years, no abnormality in 5 cases, and 1 case of ossifying fibroma recurred 2 years after surgery. Conclusion Maxillary lifting is a better surgical method for the treatment of cranial-related benign nasal and sinus tumors. Benign nasal cavity and sinus tumors invading the anterior and middle skull base are tricky to deal with clinically, and complete resection of the tumor is difficult due to the restricted operative field. We applied maxillary lifting and repositioning surgery and craniofacial joint pathway surgery to solve this problem better, and reported as follows. Data and methods I. Clinical data 1. General data: from 1989 to 1994, our department admitted 6 cases of benign tumors of nasal cavity and sinus invading into the anterior and middle skull base, 4 cases were male and 2 cases were female; the age of the patients ranged from 19 to 43 years old, with an average of 31 years old. The average age was 31 years. The duration of the disease ranged from 3 to 9 years, with an average of 5.8 years. Clinical manifestations: all 6 cases had nasal congestion, protruding eyeballs, migraine, and numbness, hyperalgesia or pain on the affected side. Other manifestations included headache, vomiting, optic nerve papillary edema in one case, visual impairment in two cases, and pain around the ear, tinnitus, and ear stuffiness in one case. 3, Site: nasal cavity, maxillary sinus, sieve sinus 2 cases, nasal cavity, maxillary sinus, sieve sinus, infratemporal fossa 2 cases, maxillary sinus, frontal sinus, orbital wall 1 case, nasal cavity, the whole group of sinuses 1 case; invasion of the anterior cranial base in 4 cases, invasion of the anterior and middle cranial base in 2 cases. 4. Imaging examination: CT or magnetic resonance imaging (MRI) was performed in all 6 cases, which could clearly show the extent of the tumor and its relationship with the surrounding tissues and structures, among which 4 cases invaded the anterior cranial base and 2 cases invaded the anterior and middle cranial bases. Pathological types: 3 cases of ossifying fibroma, 1 case of osteoma, 1 case of osteochondroma, 1 case of giant cell tumor of bone (grade I-II). Second, surgical methods Surgery was performed under general anesthesia, and all of them were operated by 1-sided maxillary lifting craniofacial joint pathway. The whole of 1 side maxilla and zygomatic bone were temporarily displaced according to 1 side maxillary partial or majority resection style. A parafacial median incision was made from the lateral side of the nose at the medial canthus of the eye down to the lateral side of the nose and around to the lower edge of the nose, and an incision was made at the junction of the middle and upper 1/3 of the upper lip; a transverse incision was made from the medial canthus, along the lower eyelid, and a horizontal incision was made in the labiobuccal gingival sulcus; a frontal, frontal sinus, or temporal incision was designed according to the invasion of the tumor into the anterior and middle cranial bases. Along the incision, about 2-3 cm of outward separation was made to expose the canine fossa, infraorbital wall, pyriform foramen, nasal prominences of both frontal bones, frontal prominences of the maxilla, and zygomatic bones. The mucosa of the lateral wall of the nasal cavity was cut to expose the nasal cavity, the maxillary frontal eminence was cut off, the medial orbital rim was disconnected with bone-biting forceps, the periosteum of the orbital floor was separated, the orbital floor plate was chiseled to the anterior end of the infraorbital fissure, and the middle part of the zygomatic bone was disconnected by bone-biting scissors or wire saws. Separate the nasal floor, the mucoperiosteum of the nasal spine, and make a longitudinal incision from anterior to posterior in the middle of the hard palate up to the posterior border of the hard palate, make a parallel incision along the junction of the soft and hard palate toward the outer 3rd molar, deep to the bone surface, and break the hard palate with a flat chisel or a wire saw. A stripper was inserted into the root of the pterygoid process above the posterior aspect of the maxillary tubercle to separate a 2- to 3-cm gap, and a bone chisel was used to open the pterygoid process. The maxilla was thus freed on 1 side, which included the anterior, posterior, and medial walls of the maxillary sinus and its hard palate. The maxilla was partially or largely displaced, taking care to maintain the maxillary-buccal myocutaneous flap connection, i.e., the maxillary-buccal maxillary myocutaneous flap, thus preserving its good blood supply. According to the primary site of the tumor and the extent of invasion of the anterior and middle skull base, the frontal craniotomy, frontotemporal craniotomy, temporal craniotomy and other approaches are designed, and frontal flap, frontotemporal flap, temporal muscle flap, etc. can be formed. Probing the frontal sinus, infratemporal fossa, and lateral part of middle cranial fossa for tumor invasion, expanding the temporal bone window if necessary, grinding away the bone of the lateral part of middle cranial base, and posterior-superior traction of the brain’s temporal lobe can probe the bone of the middle cranial base, and forward to the anterior pole area of the temporal lobe and the supraorbital fissure; and upward to the area of the posterior crus of pterygoid winglets. Thus, the tumors of intracranial and extracranial communication are jointly resected. Due to the large surgical field of the combined craniofacial approach, intraoperative bleeding was high, with a bleeding volume of 800 ml, which required tight hemostasis and supplemental bleeding. A temporalis muscle and fascia flap was made to cover the dura mater and trauma at the base of the skull, and free broad fascia could also be used for repair. At the end of the operation, the maxillary flap was inserted and repositioned, and we applied fine wire fixation. The pre-prepared titanium craniofacial fixation bracket and related screws could also be used for fixation in order to maintain a better facial appearance while completely removing the tumor. RESULTS The tumor was completely resected in 4 out of 6 cases and nearly completely resected in 2 cases. Mild occlusal malalignment occurred in 2 cases after surgery, which was corrected soon after maxillary and mandibular elastic traction, and there were no complications such as osseous nonunion, osteonecrosis and infection. After 2-3 years of follow-up, 5 cases had no abnormality, and 1 case of ossifying fibroma recurred 2 years after surgery without surgery. All patients maintained good cranial and facial appearance. DISCUSSION Sasaki [1] first reported the use of approximate 1-sided maxillary level resection followed by repositioning in 1990 to treat several patients with anterior and middle skull base tumors. In contrast, the midface uncovering procedure is indicated for bilateral sinus lesions involving the skull base. The maxillary lift is an improvement of the surgical method of Sasaki et al. The method of Sasaki et al. is to resect a large portion of the maxilla on 1 side and then align it, which has the defect of no blood supply and is prone to complications such as bone disjunction, osteonecrosis, or infection. In this group, the maxillary flap was made into a buccal maxillary-buccal muscle flap, which had a good blood supply without the above complications. The maxillary lifting and repositioning surgery, together with the combined craniofacial approach, can be used for the surgery of nasal cavity, sinus invasion and skull base, especially suitable for the surgery of the anterior and middle cranial bases; at the same time, it can also reveal the orbital cavity, infratemporal fossa, pterygopalatine fossa, and nasopharyngeal region and other parts of the lesions. Adequate exposure of the maxillary lifting and repositioning operative field minimizes the impact on function and craniofacial aesthetics. Preliminary results indicate that this method is conducive to maximum exposure of the operative field for complete tumor removal, while important structures at the base of the skull can be protected under direct vision, and the morphology and related functions of the face recovered well in the postoperative period. No complications occurred in this group, proving that this procedure is completely feasible.