Anterior Transpetrosal-Transtentorial Approach for Sphenopetroclival Meningiomas: Surgical Method and Results in 10 Patients

Abstract

This report presents a new surgical method and the results in 10 patients with petroclival meningiomas extending into the parasellar region (sphenopetroclival meningiomas). Minimal but effective extradural resection of the anterior petrous bone via a middle fossa craniotomy offered a direct view of the clival area with preservation of the temporal bridging veins and cochlear organs. The dural incision was extended anteriorly to Meckel's cave, and in cases with invasion of the cavernous sinus, Parkinson's triangle was enlarged by mobilization of the trigeminal nerve. This approach offered an excellent view from the mid-clivus to the cavernous sinus. Extra-as well as intradural tumor masses and dural attachments could be cleared under direct view of the pontine surface. The risk of injury to the lower cranial nerve and of retraction damage to the temporal lobe and brain stem were kept minimal by this approach. Total tumor resection was achieved in 7 patients, with no resultant mortality. Eight patients had a satisfactory postsurgical course, extraocular paresis being their main complaint. The extent of tumor resection depended on the degree of tumor adhesion to the carotid artery, and operative morbidity on the degree of tumor invasion of the brain stem. Of the 3 patients in whom subtotal tumor removal was achieved, only one experienced regrowth of the tumor and underwent a second operation during the follow-up period (6 months-6 years).

Cochlear line: a novel landmark for hearing preservation using the anterior petrosal approach

“…The extent of petrosectomy has been widened from the time of introduction of this approach in the neurosurgical field until recently, and this approach is known to be effective for accessing ventral mid-to upper pontine lesions in particular. 1,[4][5][6]9 In fact, when performing the anterior petrosal approach in the narrow space of the parallelogram-shaped anterior surface of the petrous bone, which is bounded by V3, the GSPN, the superior semicircular canal, and the petrous ridge, only approximately 3 cm 2 may not present a straightforward procedure with a manageable learning curve. Adding to the difficulty is the need to preserve the patient's hearing in order to maintain quality of life; a previous comprehensive review reported that 12% of patients who received an anterior petrosectomy due to brainstem cavernous malformations experienced perioperative hear- ing loss.…”

“…1 The technique provides easy access to large sphenopetroclival meningiomas, dumbbell-shaped trigeminal schwannomas, and giant acoustic neuromas located in front of the brainstem and basilar trunk aneurysms. 5,7,9 The advantage of this technique is a lower possibility of postoperative hearing loss, vestibulopathy, and facial paresis in comparison with the transcochlear approach and/ or combined middle fossa posterior approach, which both provide similar surgical fields.…”

“…1 The technique provides easy access to large sphenopetroclival meningiomas, dumbbell-shaped trigeminal schwannomas, and giant acoustic neuromas located in front of the brainstem and basilar trunk aneurysms. 5,7,9 The advantage of this technique is a lower possibility of postoperative hearing loss, vestibulopathy, and facial paresis in comparison with the transcochlear approach and/ or combined middle fossa posterior approach, which both provide similar surgical fields. 1 To perform the anterior petrosal approach more safely, the use of possible anatomical landmarks, including the maxillary branch of the trigeminal nerve (V3), gasserian ganglion, greater superficial petrosal nerve (GSPN), petrous internal carotid artery (ICA), cochlea, geniculate ganglion, dura mater of the internal acoustic canal (IAC), labyrinthine portion of the facial nerve, vestibule, and superior semicircular canal can also be put to good use.…”

Spinal Arachnoid Cyst Causing Paraplegia Following Skull Base Surgery-Case Report-

“…Neurological examination revealed bilateral papilledema, mildly decreased hearing on the right, hyperreflexia in all 1A). The tumor was subtotally removed via an anterior transpetrosal approach, 6) leaving minimal remnant tumor adherent to the brainstem and perforating arteries. Histological examination confirmed the diagnosis of secretory type meningioma.…”

Decision making for the surgical approach of posterior petrous bone meningiomas

“…2,4,8,14 Criteria for the selection of these approaches have not been addressed. The goal of this short paper is to clarify the roles of these approaches for the various subtypes of posterior petrous bone meningiomas.…”