Iwasaka District
A very specialized medical term
Specifically refers to the petrosal bone tip of the temporal bone
Posterior lower part of the surface of the sphenoid bone, as well as the occipital bone
The area where the slope parts together form it
Tumors in this area often involve many important blood vessels (basilar artery and branches, anterior inferior cerebellar artery and branches, transverse sinus, sigmoid sinus, superior petrosal sinus, inferior petrosal sinus and superior petrosal vein, inferior petrosal vein, etc.), compress cranial nerves (including facial nerve, vestibulocochlear nerve, trigeminal nerve, oculomotor nerve, trochlear nerve, abducens nerve, glossopharyngeal nerve, accessory nerve, etc.), and push the brainstem and cerebellum, etc., which increase the difficulty and risk of surgery. Meningioma in this site usually grows along the upper 2/3 slope, located above the jugular foramen, the location is deep and inaccessible, the surgical approach options are diverse and limited, and the morphology and growth characteristics of different lesions are different, and the design of surgical approach is very important for the degree of tumor resection and reduce postoperative complications.
Recently, the Department of Neurosurgery of the Third Hospital of Shanghai selected different surgical approaches according to the different locations and morphologies of the lesions, and performed surgical treatment on many patients with tumors growing in the rock oblique area, and all the tumors were resected, and there was no neurological dysfunction and other complications after surgery. The surgery went smoothly and the postoperative recovery was satisfactory.
01 Patient Li, female, 47 years old, was admitted to the hospital with "involuntary convulsions on the left side of the face for 1 year".
Physical examination on admission: clear consciousness, cooperative physical examination, involuntary convulsions on the left side of the face, and no positive signs. MR of the brain showed petrosal oblique meningioma, located anteriorly inferior to the facial nerve and vestibulocochlear nerve, and posterior to the trigeminal nerve. The posterior approach to the suboccipital sigmoid sinus is used. Fully release the cerebrospinal fluid, collapse the cerebellar tissue, without the traction of the brain tissue retractor, enter along the continuation of the cerebellum and the petrosal bone, easily glimpse the tumor, separate the peritumoral arachnoid membrane, dissociate the tumor pedicle, decompress the intratumorium, separate along the tumor edge, and completely resect. The process went smoothly, and the convulsions on the left side of the patient's face disappeared immediately after the operation, and there were no complications such as hearing loss, tinnitus, and facial paralysis.
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▲Figure 1 Preoperative MR enhancement
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▲Figure 2 Postoperative MR enhancement
02 Patient Cui, female, 56 years old, was admitted to the hospital with "right limb weakness and dysphagia for half a year".
Physical examination on admission: clear consciousness, crooked corners of the mouth to the right, loss of left gag reflex, dysphagia, choking on drinking water, hoarseness, slurred speech, right limb muscle strength grade III. After admission, a nasogastric tube was placed for nasogastric feeding to prevent lung infection caused by aspiration. Actively improve preoperative preparations. MR of the brain showed a large meningioma in the left petrosal oblique area, accumulating above and below the tentorial. Considering that the patient's tumor had spread to important structures such as the facial nerve, trigeminal nerve, glossopharyngeal nerve, and brainstem, the patient adopted the inferior temporal approach in order to reduce further intraoperative losses. Take the lateral prone position, the zygomatic arch-mastoid plane is placed at the highest point, fully grind out the petrosal bone, expose the petrosal oblique area, see the tumor originating from the muslim notch and the petrous bone migration, cut the cerebellar tentorium, block the main blood supply source from the cerebellar tentorium, perform intratumoral block resection, after full decompression, separate the trochlear nerve, trigeminal nerve, glossopharyngeal nerve, etc., and separate the tumor and pontine adhesions downstream from the arachnoid membrane, and completely remove the tumor. The operation went smoothly, and the muscle strength of the patient's right limb recovered to grade IV, the language function gradually recovered, and the gag reflex gradually improved.
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▲Figure 3 Preoperative MR enhancement
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▲Fig. 4 Postoperative MR enhancement
03 Patient Lu Moumou, female, 51 years old, was admitted to the hospital with "pain on the right side of the face for half a year".
Physical examination on admission: clear, cooperative physical examination, pain on the right side of the face, cautery, persistent, normal muscle strength and muscle tone of the limbs. After admission, we will actively improve our preoperative preparations. Cranial MR showed a meningioma in the right petrosal oblique area, and the main body of the tumor was located under the tentorial of the cerebellum, which was closely related to the internal auditory canal due to deformation caused by compression of the trigeminal nerve and displaced to the midline. Considering that the patient's tumor involves important structures such as the facial nerve, trigeminal nerve, and brainstem. Take the left prone position, the right posterior approach of the suboccipital sigmoid sinus, fully expose the transverse sinus and sigmoid sinus, enter along the lateral edge of the cerebellar tentorial, fully release the cerebrospinal fluid, the cerebellar tissue naturally collapses, no need to retract the device, the petrosal oblique area is fully exposed, and the blood supply to the tumor pedicle is blocked, the intratumoral block is resected and decompressed, separated along the tumor capsule, and finally completely resected. The operation went smoothly, the bleeding was well controlled, and the total intraoperative bleeding was less than 20ml. After the operation, the patient's right facial pain disappeared, and there were no complications such as facial paralysis, tinnitus, and hearing loss.
Fig. 5 Preoperative skull base CT
Suggests that the tumor is adjacent to the internal auditory canal and that the internal auditory canal is not enlarged
▲Fig. 6 Preoperative nerve MR thin-slice scan T2
Yellow arrows point to round-like tumors
The red arrow points to the right trigeminal nerve
The green arrow points to the auditory nerve on the face of the internal auditory tract
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Fig. 7 Preoperative MR enhancement
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Figure 8 Postoperative MR enhancement
Because of its deep location and complex anatomical relationship, meningioma in the petrosal oblique area often accumulates important structures such as nerves, blood vessels, and brainstems, which makes surgery difficult, high-risk, and has many and serious postoperative complications.
We do it for every patient
1. Adequate preparation before surgery
This is also the most important, for example, to find out the location of the origin of the tumor, what is the blood supply, and which nerves are affected before surgery, which all indicate which step to do first during the operation, and we need to stop when we reach certain locations, and confirm whether it is a nerve through nerve electrophysiological testing;
2. Be bold and careful during the operation
When operating inside the tumor, it will not hurt the nerves and blood vessels, and we can boldly carry out intratumor resection, and when it comes to tumor capsule separation, especially when separating from neurovascular, we need to be especially careful, and even take the trouble to repeatedly perform electrical stimulation detection to clarify the location and travel of the nerve, so as to reduce the disturbance and loss of nerves during the operation as much as possible;
3. Exercise should be resumed early after surgery
Neurological rehabilitation should be carried out as soon as possible for those with neurological dysfunction, and early eating, getting out of bed, and exercising early should be required to minimize and alleviate postoperative complications.
The Department of Neurosurgery of the Third Hospital of Xi'an, whether it is hardware facilities or staffing, has been very proficient in carrying out the resection surgery of tumors in the petrosal oblique area.
Expert presentation
Gao Haifeng, Deputy Chief Physician of the Department of Neurosurgery of Xi'an Third Hospital, Master Candidate, Deputy Chief Physician of Neurosurgery, Member of the Skull Base Surgery Branch of the Chinese Medical Doctor Association, and Member of the Neurosurgery Branch of the Xi'an Medical Association. He has been engaged in clinical and scientific research in neurosurgery for 15 years and neuroendoscopy for 13 years. Participated in the completion of 2 projects of Shaanxi Provincial Natural Science Foundation and 1 project of basic exploration of Xijing Hospital's Discipline Booster Program. In 2018, he won the championship in the endoscopy knowledge competition at the China Neuroendoscopy Annual Conference.
Specialty: Minimally invasive neuroendoscopic treatment of cerebral hemorrhage, pituitary tumor, craniopharyngioma, skull base meningioma, chordoma, slope tumor, orbital tumor, optic canal decompression, cerebrospinal fluid rhinorrhea repair and other surgical treatments. Ventricular soft microscopy removes intraventricular hematoma, abscess, triventricular floor stoma, hydrocephalus, etc. Craniotomy to remove glioma, meningioma, hemangioma and vascular malformations. Emergency treatment for traumatic head injury.
Contact number: 15029950288
Outpatient hours: Monday morning for specialist outpatient clinics and Wednesday mornings for specialist outpatient clinics
Chinese business all-media reporter Chen Mengyang
According to the Third Hospital of Xi'an