clivus tumor resection

The primary dura mater tumors in the rock slope area are meningioma, schwannomas and cholesteatoma, and the epidural tumors are more common in chordoma, osteochondroma, chondroma, chondrosarcoma and giant cell tumor. The tumor in this part is deep in the midline of the skull base, adjacent to the brain stem, vertebral-basal artery, cranial nerve and other important structures, and the surgical treatment is quite tricky. Although with the rapid development of skull base surgery and microsurgery technology, there have been more and more reports of successful removal of rock bone slope tumors at home and abroad, but some tumors are still very difficult to cure. Treatment of diseases: pediatric meningioma multiple meningioma meningioma Indication The surgical approach of rock bone slope tumors can be roughly divided into subdural and epidural. The patient's clinical symptoms, signs and imaging data should be carefully analyzed before surgery to determine the location and extent of the tumor. To understand the origin and nature of the tumor as much as possible, refer to the above table and select the appropriate surgical approach. In principle, epidural tumors mainly use the epidural approach, while intradural tumors use the dural approach. But not always, some tumors need to adopt a joint approach. Contraindications 1. Oropharynx, nasal cavity, paranasal sinus, mastoid inflammation, can not be treated according to the corresponding approach. 2. A wide range of benign tumors and tumors that extend to the bilateral cavernous sinus should be treated with caution. A wide range of malignant tumors is not suitable for surgery. Preoperative preparation 1. Surgery through the contaminated cavity (mouth, nose, paranasal sinus), 1 week before surgery with an antibiotic solution gargle, spray or nose, 3 days before surgery, systemic antibiotics. 2. If the tumor is closely related to the carotid artery or vertebral-basal artery, cerebral angiography should be performed before surgery to understand the tumor blood supply, the relationship with important blood vessels and the vascular involvement. During the operation, it may be possible to temporarily clip the internal carotid artery or vertebral-basal artery, or may damage important blood vessels. If you need to consider how to treat damaged blood vessels (clamping or repair), you should do the internal carotid artery or vertebral-basal artery balloon. The occlusion test was performed to observe clinical symptoms and changes in cerebral blood flow after occlusion. If the tumor is rich in blood supply, it should be done before surgery. To prepare to cut the transverse sinus or sigmoid sinus, you need to understand the patency of the contralateral transverse sinus and sigmoid sinus. 3. Those who need to cut tissue in other parts to reconstruct the skull base should do the skin preparation work of the corresponding parts. 4. Prepare for intraoperative monitoring (such as brain stem evoked potential monitoring). Surgical procedure 1. Via the underarm or improve the underarm (rock tip - cerebellum) approach Resection of the slope tumor through the submental approach was similar to the removal of the cranial fossa and the cerebellar incision in the subdural subdural approach. However, because the origin and growth direction of the tumor are different, the relationship between the tumor and the important blood vessels and nerves in the incision area is different, so it is necessary to pay attention to identification. Specific steps are as follows: (1) Flap and bone flap: supine, the shoulder of the operation side is raised, and the head is rotated 45° to the opposite side. The ankle flap and bone flap were made as usual, and the lower part of the scale was removed to the bottom of the cranial fossa. If it does not affect the exposure, try not to bite the mastoid air chamber. Once open, it should be sealed. (2) Resection of the rock tip: the dura mater in the middle of the cranial fossa is separated, and the middle meningeal artery is cut off by electrocoagulation. Sometimes it is necessary to cut off the rock (shallow) large nerves to avoid damage to the facial nerve when the dura mater is isolated. After exposing the front part of the rock bone, it is removed by high-speed micro drill. Abrasive range: the front boundary is a trigeminal nerve impression, the posterior boundary is an arched bulge, the outer side is a rocky ditch (rock shallow nerve indentation), and the lower part is a carotid artery and an internal auditory canal. The bone of the rock tip is softer than the middle part of the rock. It has reference significance when grasping the scope of resection. As long as the scope of resection is strictly controlled, important structures will not be damaged. During the bone resection process, tumors that appear outside the epidural and eroded rock tips can be seen. (3) Tumor exposure and resection: After the removal of the rock tip, the dura mater is cut along the superior sinus. Cut off or sew the ends of the upper sinus of the rock and cut it off (note that the position of the rear end clamp or suture should be selected before the rock vein joins the upper sinus of the rock). The cerebellum was cut along the posterior border of the tumor until the free margin, and the two lobe of the cerebellum were retracted with sutures to reveal the tumor of the posterior fossa. After the tumor body is excised, the dura mater at the base of the tumor is removed. (4) Guan Guan: If the air chamber is open during operation, it needs to be closed with bone wax or blocked with muscle block, and covered with diaphragmatic muscle flap. The dura mater is sutured with the temporalis fascia. The bone flap was fixed and fixed. The flap was sutured and sutured. 2. Under the occipital (posterior mastoid) approach or under the occipital approach It is similar to the suboccipital lateral (post-emulsion) approach for the removal of acoustic neuroma. After incision of the dura mater of the posterior cranial fossa, the tumor descending the lower third of the slope and the leading edge of the occipital foramen was obtained under the posterior cranial nerve. After the posterior cranial nerve and the face-acoustic nerve were removed, one third of the tumor was removed. Higher-position tumors can be removed between the facial-acoustic and trigeminal nerves. If the tumor is raised on the small brain, there is a considerable gap between the trigeminal nerve and the cerebellum. If the cerebellum is cut from below, the gap is larger, and the tumor in the cerebellar incision area can be reached and removed through the gap. The main steps are as follows: (1) Incision and bone resection: lateral position, the operation side is on. There are two types of skin incisions: the midline straight incision is equivalent to the neck 4 level, and the upper to the occipital trochanter is folded outward and upward to the mastoid. Or from the 4cm below the tip of the mastoid, along the anterior border of the sternocleidomastoid to the base of the mastoid, and then to the midline along the upper line. The skin, muscles and periosteum were dissected and resected to the sides after separation under the periosteum to reveal the occipital scaly, the posterior mastoid and the posterior arch of the neck. The lateral occipital squamous (including the posterior margin of the foramen magnum), the posterior margin of the occipital condyle and the posterior margin of the mastoid were completely exposed to the sigmoid sinus. (2) vertebral artery exposure and traction: Separate the neck 1 posterior arch, from the midline to the transverse process, first separate the lower edge, then separate the upper edge, and separate the vertebral artery. Separation should be performed under the periosteum to avoid damage to the vertebral artery and paraspinal plexus. When separating the vertebral artery, there are two special points to be paid attention to: one is that the vertebral artery leaves the vertebral artery groove of the posterior arch of the neck 1 (about 35% to 50% of the vertebral artery is partially or completely wrapped by the posterior arch) and is folded toward the dura mater. It is equivalent to the lateral side of the neck 1 posterior arch height increase, where there is often a branch of the vertebral artery - the Salmon artery. The second is that the vertebral artery passes through the dura mater into the intracranial region. Because the vertebral artery sheath and the dura mater are tightly attached, do not attempt to completely dissect the vertebral artery when separating. It is best to leave the vertebral artery a few millimeters when cutting the dura mater. After the vertebral artery is separated, it is pulled outward and upward, and the tumor is removed from the side of the medulla and the vertebral artery. (3) sigmoid sinus exposure or severance: After the sigmoid sinus is exposed, the dura mater is cut in front of or behind it to reveal the tumor. The sigmoid sinus can be cut off if necessary to obtain a wider exposure. The cut position is generally at the junction of the vertical section and the horizontal section, the vertical section is sewed or clamped at the broken end, and the horizontal section is filled with gelatin sponge. 3. Through the rock bone - the cerebellum Slope-rock tip tumors often involve the cerebellum at the same time, so many scholars use the upper and lower joint approach. Hakuba (1975) and Al-Mefty (1988) improved Morrison (1973) on the basis of the labyrinthine-clinical approach to reveal the cerebral cerebral cerebral horn. The rock-cyloid approach was used to remove the slope-rock tip tumor. That is, before the removal of the tumor on the screen or under the curtain, the partial removal of the humerus is performed first, and the advantages are: 1 pulling the cerebellum and temporal lobe light; 2 shortening the surgical distance to the slope by 3 cm; 3 lateral revealing can make the surgeon The visual axis directly targets the front and side of the lesion and brainstem; 4 can block the blood supply of the tumor early; 5 does not affect the cochlea, vestibular and facial nerve canal, and does not cut the transverse sinus or sigmoid sinus. (1) Flap and bone flap: supine, the shoulder of the operation side is high, the head is inclined to the opposite side and rotated 40°~60°, so that the rock bone is at the highest point of the surgical field. The incision begins with the zygomatic arch, rounds back and forth around the auricle, and then stops down 1 cm behind the mastoid. The diaphragm is peeled and turned down. Drill 2 holes in the skull on both sides of the transverse sinus, use the craniotomy cutter to first cut the humerus and part of the occipital occipital bone, then saw the occipital bone under the curtain, and finally bite the bone between the bones at both ends of the transverse sinus. The rongeur bites open and forms a complete free bone flap to remove. There is often obvious adhesion between the dura mater and the skull at the transverse sinus-sigmoid sinus movement, and attention should be paid when forming the sacral bone flap. (2) mastoid and bone resection: the mastoid is removed, the sigmoid sinus is revealed until the jugular bulb and the Citelli sinus-dural angle, according to which the position of the superior sinus can be determined. The superficial group of the mastoids behind the external auditory canal and the deep group of air cells behind the facial nerve can be removed to reveal the facial nerve canal and the external and posterior semicircular canals (Fig. 4.3.3.9-13). Continue to remove the rock bone along the rock cone toward the tip of the rock, paying attention to the facial nerve, middle and inner ear. The open air chamber is sealed with bone wax. (3) Dural incision and tumor exposure: If the distance between the arrival slope and the rock tip is further shortened, the dura mater can be cut at the anterior edge of the sigmoid sinus, and the incision is extended to meet the subdural dura mater. Clipping or electrocoagulation on the upper sinus and then traversing. Cut the cerebellum in parallel with the rock to the free edge. The sigmoid sinus, cerebellum, and craniotomy are held together by the self-sustaining retractor. (4) Tumor resection: The electrocoagulation tumor is at the base of the rock cone, the slope, and the blood supply artery from the cerebellum. If the tumor is small and medium, the face and the auditory nerve are generally squeezed to the back and are easily recognizable. If it is large, it can be surrounded by tumors. Select the appropriate site, cut the arachnoid and tumor capsule on the surface of the tumor, and use CUSA, aspirator or laser to perform the resection of the intracapsular tumor. Be careful not to damage the surface, auditory nerve and basilar artery that may be completely surrounded by the tumor. The inferior cerebellar anterior artery and the inferior cerebellar artery. If the tumor is extended to the screen, after the part of the tumor is resected, the cerebellum is cut along the circumference of the tumor until the edge of the curtain. Be careful not to damage the trochlear nerve. After the cerebellum is cut, the front and side of the tumor upper pole and brain stem can be well exposed. At this point, the tumor envelope can be isolated. To protect important neurovascular vessels, separation should be performed as far as possible in the arachnoid interface. After a portion of the envelope has been separated, most of the envelope may be excised, rather than entirely, to avoid missing the exact interface for further separation. The posterior cranial nerve is closely related to the tumor's lower pole. It should be gently separated and protected. Do not stimulate the vagus nerve too much to avoid hypotension and bradycardia. The abductor is often in front of the tumor, and the trigeminal nerve is squeezed to the outside. The basilar artery is squeezed to the opposite side if it is not surrounded by the tumor, and should be carefully separated and protected. If the tumor invades the internal auditory canal, the posterior wall should be ground to remove the residual tumor. Tumors that extend to the jugular foramen should also be removed separately. (5) Guan skull: After the tumor is resected, the dura mater is tightly sutured, and a part of the diaphragm is covered on the rock bone. The bone flap was fixed and sutured, and the scalp was sutured. 4. After the ear - pre-ear rock bone - cerebellar joint approach (1) flap and vascular muscle periosteal flap: the patient takes the "park-bench" position - side lying, the affected side is on, the head and neck and upper chest are turned to the opposite side, the head is drooping 35°, with the head After the frame is fixed, raise the bed to keep the head in the horizontal position. The skin incision starts from the zygomatic arch and extends along the apical branch of the superficial temporal artery until it approaches the midline. The lower end of the incision is extended to the front of the earlobe. Be careful not to damage the superficial movements and veins, and to preserve the soft tissue around the blood vessels. About 7 cm above the zygomatic arch, the superficial movement, the vein and the soft tissue covering it were separated from the deep fascia fascia, and a 7 cm × 5 cm periosteum was cut and connected to the distal end of the blood vessel. Cut the 1/3 diaphragm muscle in the plane of the zygomatic arch, and cut it upward along the direction of the muscle fiber, separate from the tibia, maintain the connection between the diaphragm, blood vessel and periosteal flap. Turn the musculoskeletal flap together with the blood vessel to the outside, with saline gauze. cover. The lower end of the skin incision was extended posteriorly, through the earlobe and the mastoid tip, obliquely upward 1 cm behind the mastoid. The suboccipital muscle was dissected, and after separation, the flap was turned upward, and the external auditory canal was cut at the cartilage-bone junction. The auricle was also pulled upward, and the mastoid tip was crossed, and was pulled down with the sternocleidomast muscle. (2) Bone flap: Use a wire saw to cut the ends of the zygomatic arch and pull it downward. Drill a few holes in the suboccipital and frontal cranial skull: the first hole is 3 mm below the distal end of the mastoid, corresponding to the junction of the transverse sinus and the sigmoid sinus, the second hole is at the posterior edge of the base of the mastoid, the third hole Just above the root of the zygomatic arch, the fourth hole is behind the frontal condyle. The skull is drilled into a suboccipital-sacral-winged bone flap that is connected to the anterior 2/3 diaphragm and turned to the outside to reveal the Trautman triangle. Excision of the mastoid with an osteotome or a burr is performed to reveal the full length of the sigmoid sinus to the jugular bulb. (3) After the ear bone resection; the posterior lateral part of the rock bone was excised with an osteotome and a grinding drill, and the posterior wall of the external auditory canal was kept about 5 mm thick. The posterior medial section of the rock bone should not exceed 10 mm below the rock raft and go to the outer vestibule small tube. The dura mater of the middle cranial fossa is pulled forward, and the posterior dura mater and sigmoid sinus are pulled inward, and the residual rock bones are removed, including the endolymphatic vessels, the posterior and upper semicircular canals, the medial part of the outer semicircular canal and the jugular bulb. In the posterior wall of the internal auditory canal, the depth of the bone resection is about 10 mm, and the internal auditory canal is cut about 5 mm before the inner auditory canal is open. Although the posterior wall of the sinus sinus is also open, the small bones are not affected. (4) Pre-ear rock excision: the dura mater of the middle cranial fossa is separated, and the shallow nerve and the middle meningeal artery are cut off to reveal the front of the rock bone. Anatomy of the posterior margin of the foramen ovale revealed the trigeminal nerve impression. The rock bone is removed from the inside of the internal carotid artery of the sacral section until the sinus of the sinus between the internal auditory canal and the rock tip. Be careful not to open the anterior wall of the cochlea. Continue to dissect and find the internal carotid artery in the deep side of the half moon. Electrocoagulation cuts off the tumor supplying artery through the rock tip and removes the tumor invading the rock. (5) Dural and cerebellar incision: The dura mater of the posterior trigone of the rock bone surrounded by the upper sinus, the inferior sinus and the sigmoid sinus is cut along the anterior sigmoid sinus. The incision is extended, along the upper sinus of the rock to the medial side, to the inner auditory canal and the semilunar section. Be careful not to damage the anterior inferior cerebellar artery that may adhere to the dura mater on the sinus. Cut the dura mater as far as possible to avoid damage to the Labbé vein, and the posterior end of the incision extends inwardly to the front end of the posterior canal. At this point, the upper sinus of the rock is ligated with two stitches, and the cerebellum is cut open until the curtain is not damaged. The posterior dural incision continues to extend to the upper and lower sinus confluences, the outer edge of the posterior wall of the cavernous sinus, revealing the deep internal carotid artery. Bleeding from the cavernous sinus can be controlled by oppression. The main blood supply artery of the tumor, the pituitary gland, is cut off after electrocoagulation, and the tumor invading the cavernous sinus is removed. Gently lift the temporal lobe and the tumor after the slope is well exposed. (6) Tumor resection: The most difficult step in resection of a meningioma is to separate the tumor capsule from the brainstem, cranial nerves, major blood vessels and their branches. The cranial god is often pushed to thin by the tumor, and some even "fused" with the tumor capsule, which is difficult to confirm even under the microscope. When separating, a piece of capsule adhered to the cranial nerve may be left, and the part of the envelope is separated and removed after the tumor body is removed. A similar method can be used to separate the pial vascular and the perforating artery that adhere to the envelope. The dura mater and the affected skull at the base of the tumor are removed as much as possible, and electrocoagulation is used when the tumor cannot be removed. (7) Reconstruction and suture: After the tumor was resected, the periosteum with vascular periosteal periosteum flap formed during craniotomy was used to repair the dural defect, and the muscle was filled to cover the first 2/3 of the bone defect. An additional incision is made along the anterior border of the sternocleidomastoid muscle, until the lower part of the neck, the lower end of the sternocleidomastoid muscle is broken 1/3, turned upward, and the residual cavity caused by the 1/3 of the rock bone and the mastoid resection after filling . The bone debris left during mastoidectomy is also placed on the surface of the sigmoid sinus and residual mastoid. The suboccipital--wing flap was fixed and fixed, and the zygomatic arch was fixed. Suture mouth. 5. Oral-pharyngeal approach For the specific method of excision of the lower slope and ventral tumor of the occipital foramen by the oropharyngeal approach, see "Oral orthodontic odontectomy". After the anterior arch of the atlas, the odontoid process and the lower end of the slope were removed and micro-milled, the tumor was removed by CUSA, tumor-clamping forceps, and stripper. After resection of the slope tumor by the oropharynx, as long as the lateral and posterior bone joints at the junction of the cranial and cervical junctions are normal, the stability is generally not affected, so there is no need for posterior fusion. 6. Under the forehead of the skull base approach Derome (1977) first used the inferior skull base approach to remove slope tumors involving the sphenoid and sphenoid sinus. This approach can reveal most of the sphenoid body and slope, and even reach the anterior border of the occipital foramen and the anterior arch of the atlas. However, to reach the lower end of the slope, after all, the field is deep, and the upper end of the slope is difficult to be exposed due to the bottom of the saddle. The sides are restricted by the optic nerve, internal carotid artery and cavernous sinus. Therefore, it is mainly suitable for extending into the sphenoid sinus and ethmoid sinus. Downhill epidural tumor. For the specific method, see "Front skull base approach" in "Cranial Nasal Tumor Resection". After lifting and lifting the dura mater of the anterior cranial fossa, the sphenoidal plate and part of the anterior wall of the sella are removed to reveal the tumor invading the sphenoid sinus. After excising the part of the tumor, it continues to be separated backwards and downwards, and the tumor of the resection slope can be reached. 7. Trans-cervical approach Stevenson and Stoney (1966) first successfully resected a case of sloping chordoma via the cervical approach. Fox (1967) and Wissinger (1967) also used this approach to clamp a basement aneurysm. The advantage is that it avoids the contaminated cavity such as mouth and nose, and the repair of the dura mater is also relatively easy. The disadvantage is that the field is deep and the exposure is limited, especially on the upper side and the opposite side. The surgeon must remove the slope on the inside of the occipital joint to avoid damage to the structure of the hypoglossal nerve and the jugular foramen. Mainly used for lower slope tumors, but also for slope odontoid skull base, atlantoaxial dislocation, odontoid fracture and basilar aneurysm. (1) Incision: supine, head over 15° and rotated 20° to the opposite side. From the tip of the mastoid down, to the plane of the thyroid cartilage, the skin and platysma are cut along the anterior border of the sternocleidomastoid muscle. Can also be from the tip of the mastoid to the jaw joint, 1 ~ 1.5cm from the lower edge of the mandible, make a horizontal arc-shaped incision, and then at the midpoint of the incision, along the anterior border of the sternocleidomastoid for a long incision, reach The neck 6 is transverse to the plane. (2) revealing the posterior pharyngeal and parapharyngeal space: after the skin and platysma are turned over, before the sternocleidomastoid muscle, the carotid sheath and the thyroid gland, the trachea are separated from the deep fascia of the neck, and the free common carotid artery And the internal and external carotid arteries, ligature and cut off the superior thyroid artery and the lingual artery (there is a fashion to cut off the facial artery). Confirm the sublingual nerve across the carotid sheath, and push forward and upward, and continue to dissect the internal carotid artery until the external port of the carotid artery. The submandibular gland is retracted, the pharyngeal muscle attached to the upper corner of the thyroid cartilage and the stalk and lingual muscle attached to the hyoid bone are cut, and the throat is pulled forward to the front and touches the front of the cervical vertebra. The pharyngeal buccal fascia was bluntly separated upwards from the anterior fascia until the attachment of the superior pharyngeal muscles to the pharyngeal nodules (the lower surface of the slope about 2 cm in front of the large occipital margin), allowing the posterior pharyngeal space to open. (3) Further revealing the posterior pharyngeal space: dissect in front of and above the pharyngeal nodule, separating the pharyngeal mucosa and periosteum from the slope, revealing the ventral side of the slope until the vomer can be reached. Be careful not to continue to dissect forward to avoid damage to the pharyngeal mucosa and into the nasopharyngeal cavity. Retract the nasopharynx tissue with a deep retractor and touch the hornbone of the bilateral sphenoid wing. The anatomical range of the lower slope surface is slightly above the two spine lines. (4) Revealing the slope and the iliac crest: the anterior arch of the occipital bone is descended from the anterior arch of the atlas to the vertebral body of the cervical vertebra, and the anterior fascia is cut along the midline. After subperiosteal separation, the anterior rectus muscle, the longus muscle, and the long neck muscle are retracted outward with a small self-sustaining retractor to expose the front of the slope, the atlas and the atlantoaxial. (5) Bone resection and tumor resection: adjust the head position, extend 5°, and rotate 10° to the opposite side. The anterior arch of the atlas was rubbed 2 cm from the center line, and the odontoid process was revealed after removal. The dentate process is abraded at the base, the ligaments of the ligaments and the cusps are cut, and the odontoids are removed. The upper half of the transverse section of the cruciate ligament was incised to reveal the lamella and the posterior longitudinal ligament. (6) suture incision: after the tumor is resected, the bone window is built into the fascial muscle block (such as the dura mater is open, need to be bound with fibrin glue) or gelatin sponge. Intervertebral muscle and fascia interrupted suture. The superior pharyngeal muscle is sutured to the anterior fascia of the foramen of the foramen magnum, and the pharyngeal buccal fascia is sutured to the anterior fascia to close the posterior pharyngeal space Soft tissue, trachea, and pharynx in the neck. The platysma and the skin are sutured intermittently. 8. Through the armpits (1) flap and facial nerve displacement: supine position, under the shoulder of the surgical side, the head is turned to the opposite side. Make a "C" shaped incision behind the ear, extending up to the ankle area and extending down to the jaw. Freed under the skin. The external auditory canal was cut at the cartilage-bone junction, and the end of the cartilage was closed by suturing, and a periosteal flap was placed over it to cover the needle. The main nerve of the facial nerve was found in the posterior fossa of the mandible, and the upper branch was dissected to the distal end, and the frontal branch was completely dissociated and then pulled downward. (2) The zygomatic arch is broken: the ends of the zygomatic arch are cut with a wire saw and turned down with the masseter muscle. The diaphragm is also turned downwards after being removed from the axilla, covering the facial nerve branch that has been moved down. (3) Subtotal resection of the rock bone: the residual skin, tympanic membrane, malleus, anvil and humerus arch in the external auditory canal. The sternocleidomastoid muscle was disconnected and the mastoid tip was removed. The lower ankle bone flap and the suboccipital bone window were made to reveal the transverse sinus and the sigmoid sinus. Grind the facial nerve tube from the geniculate ganglion to the stalk hole. (4) Internal carotid artery exposure: the joint bone is removed, the temporomandibular joint is exposed, and the mandibular condyle is pulled downward with the infraorbital fossa retractor. If the exposure is insufficient, the mandibular condyle can be removed. The rock bones of the anterior lateral part of the internal carotid artery were removed. The inner cartilage of the Eustachian tube is separated from the internal carotid artery of the horizontal section of the rock bone until the rupture hole. Fill the eustachian tube with bone wax. 5) Tumor exposure and resection: the mandibular nerve and the meningeal artery are cut off, and are pulled down together with the sacral muscle and the eustachian tube cartilage. If necessary, the pterygoids are removed to reveal the tumor in the infraorbital fossa and the front of the slope. , CUSA, aspirator, etc. are gradually removed, and the eroded bone can be removed by grinding, taking care not to damage the internal carotid artery at the contralateral rupture. (6) suture incision: If the dura mater is open, take a diaphragmatic fascia or freeze-dried dura mater over the lesion and glue with fibrin glue. Abdominal fat and pedicled diaphragm were used to fill the cavity. Reduction of the temporomandibular joint. The zygomatic arch is fixed and fixed. The flap was sutured and sutured. 9. Transsacral approach (1) Flap: A question mark-shaped incision is made from the ankle, extending to the back of the ear and the mastoid region, and then extending between the sternocleidomastoid muscle and the mandible. Separate under the skin, cut off the external auditory canal, and turn the auricle and the flap together. (2) Anatomy of the vascular nerve in the neck: The periosteum at the base of the mastoid is cut horizontally, and the periosteum above the incision and the posterior part of the diaphragm are freed and then pulled forward together for the purpose of repairing the tumor after resection. The periosteum and sternocleidomastoid muscles below the incision are separated from the mastoid and then pulled downward, keeping the accessory nerves. Cut off the abdomen of the second abdominal muscles. The facial nerve was found from the stem of the stem, and the main branch was dissected in the direction of the parotid gland, and the shallow lobe of the parotid gland was removed. The internal and external carotid arteries, the internal jugular vein and the 9th to 12th cranial nerves were dissected. (3) bone window formation and mastoid resection: after the mastoid and the small bone window of the ankle, and then resected the mastoid, fully revealing the transverse sinus, sigmoid sinus, jugular bulb. (4) Rock bone resection: excision of the skin, tympanic membrane and ossicular chain in the external auditory canal. The facial nerve canal is opened from the stem of the stem through the mastoid and middle ear to the geniculate ganglia. If you want to reveal the middle slope, you need to get rid of the lost road, reveal the internal auditory canal, free the facial nerve to the geniculate ganglion, cut off the shallow nerve and the tympanic nerve, and move the facial nerve to the back. Cut off the cochlea and vestibular nerves in the inner auditory canal. The eustachian tube opening was found in the anterior wall of the tympanic cavity and blocked with muscle blocks. Remove the styloid process. The tympanic bone and the external auditory canal are removed, and the vertical and curved parts of the internal carotid artery of the rock bone segment are exposed, and the cochlea is removed to reveal the horizontal part of the internal carotid artery. After the cochlea is completely removed, a relatively fragile slope can be revealed. After the slope is removed, the sphenoid sinus mucosa and the posterior pharyngeal space are in front, and the posterior cranial fossa is convenient. If the slope is revealed, the facial nerve is moved forward and upward, and it is not necessary to remove the cochlea, get lost, or cut off the cochlea and vestibular nerve to preserve sensorineural hearing. However, the sigmoid sinus and internal jugular vein should be ligated and cut. (5) Tumor resection: Epidural tumors can be removed after reaching the slope. If the tumor is in the dura of the mid-slope, the dura mater can be cut in front of the sigmoid sinus. If it is in the dura mater of the lower slope, the sigmoid sinus and the internal jugular vein should be ligated, and the 9th to 11th cranial nerves should be completely removed from the brainstem to the jugular foramen, and the posterior medial aspect should be taken. This can avoid the removal of the tumor between the cranial nerves. . (6) suture incision: after the tumor is resected, the dura mater is sutured. The posterior aspect of the diaphragm was transferred posteriorly to the posterior and sternocleidal muscles. Abdominal wall fat or a vascular muscle flap is used to fill the cavity left after the bone is removed. Suture the incision.