Microsurgical Resection of Giant Petroclival Meningioma via the Posterior Petrosal Approach: 2-Dimensional Operative Video.

Petroclival meningiomas are challenging deep-seated lesions related to many critical neurovascular structures of the skull base.1-5 We present the case of a 45-year-old male presenting with a 3-year history of progressive headache associated gradually with multiple cranial nerves deficits and progressive tetraparesis leading to use of a wheelchair (Video 1) Preoperative magnetic resonance imaging demonstrated a mass highly suggestive of a giant left petroclival meningioma. Considering worsening of symptoms and impressive mass effect, microsurgical resection employing the posterior petrosal approach was performed. Mastoidectomy with skeletonization of semicircular canals and a craniotomy approaching both posterior and middle cranial fossae were done. Dural incision at the base of the temporal lobe was communicated to other incision in the presigmoid dura by ligation and sectioning of superior petrosal sinus. Tentorium was cut all the way toward the incisura, with attention to preserve the fifth nerve along its division and fourth nerve in the last cut. After a complete tentorium incision, the presigmoid space enlarged, exposing both supratentorial and infratentorial spaces. The lesion was totally resected employing microsurgical techniques. Postoperative magnetic resonance imaging demonstrated complete tumor resection. The patient experienced improvement of complaints and no new neurologic deficit on follow-up. The posterior petrosal approach gives great exposure and a more lateral angle of attack to the ventral surface of brainstem, allowing in this case to approach the whole tumor attachment. Informed consent was obtained from the patient for the procedure and publication of this operative video. Anatomic images were courtesy of the Rhoton Collection, American Association of Neurological Surgeons/Neurosurgical Research and Education Foundation.

Microsurgical Resection of Intracanalicular Vestibular Schwannoma via Retrosigmoid Approach: 3-Dimensional Operative Video.

Vestibular schwannomas are a multifaceted group of tumors that can present with different sizes and involvement of critical neurovascular structures.1-6 While operating on these tumors, a critical goal is postoperative preservation of facial nerve function and hearing. We present the case of a 66-year-old male with a history of severe left-sided tinnitus and progressive hearing loss (Video 1). Preoperative imaging depicted a lesion highly suggestive of an intracanalicular vestibular schwannoma. Due to worsening of symptoms and after thoughtful discussion with the patient, microsurgical resection was indicated under constant neurophysiologic monitoring. A retrosigmoid approach was employed, and the posterior wall of the internal auditory canal was opened, allowing exposure of tumor and its total resection. Postoperative imaging demonstrated complete tumor resection. The patient's symptoms improve, and there were no new neurologic deficits on follow-up. Anatomical images were a Courtesy of the Rhoton Collection, American Association of Neurological Surgeons (AANS)/Neurosurgical Research and Education Foundation (NREF).

Microsurgical Resection of Trigeminal Schwannoma via Anterior Petrosal Approach: 2-Dimensional Operative Video.

Trigeminal schwannomas are complex lesions that may be related to many critical neurovascular structures. We present the case of a 59-year-old male presenting a history of left-sided trigeminal neuralgia. Preoperative imaging demonstrated a mass highly suggestive of a trigeminal schwannoma, and microsurgical resection was indicated considering the progressive symptomatology and important mass effect (Video 1). A middle fossa route including an anterior petrosectomy was chosen. The patient was placed supine with the head rotated to the contralateral side, and an arcuate incision was performed. A V-shaped zygomatic osteotomy was done to mobilize the temporalis muscle more inferiorly and better expose the middle fossa floor. Following craniotomy, peeling of the dura propria from the lateral wall of cavernous sinus was carried out starting by coagulation of middle meningeal artery. Some tumor was already identified and removed, and then the anterior petrosectomy was performed until we exposed the posterior fossa dura. The middle fossa dural incision was connected with the other one at the posterior fossa dura, by coagulation of the superior petrosal sinus. The tentorium was completely cut toward the incisura. After lesion debulking, the tumor was progressively removed by peeling the arachnoid from the lesion to maintain arachnoid planes and preserve the nerves and their blood supply. Postoperative imaging demonstrated complete tumor resection. The patient's symptoms improved, and there were no neurologic deficits on follow-up. Extensive laboratory training is fundamental to be familiarized with the normal anatomic nuances and prepared to face the anatomy distorted by lesion. Informed consent was obtained from the patient for the procedure and publication of this operative video.

Endolymphatic Sac Tumour: A Case Report and Review of the Literature

Introduction Endolymphatic sac tumor (ELST) is a slow-growing, low-grade, locallyinfiltrative tumor arising from the endolymphatic sac/duct, which is located in the posterior part of the petrous temporal bone. It may be sporadic in origin, or may be associated with Von-Hippel Lindau (VHL) syndrome. Case description A 40-year-old female patient with an ELST without VHL syndrome who was treated successfully by microsurgical extirpation of the tumor. Discussion We discuss the radiological features and the histopathology of this rare tumor and review the relevant literature. Conclusion The case herein reported adds to the previously-reported cases of this rare tumor.

Total Petrosectomy for the Total Resection of Sphenopetroclival Meningioma: 2-Dimensional Operative Video.

Sphenopetroclival meningioma is a most formidable meningioma. Many patients have few preoperative deficits and surgery has the potential of severe neurological complications. Surgical treatment is challenging due to brainstem compression, the involvement of multiple cranial nerves and cerebral vessels. Wide tumor exposure, multiple dissection axis, and short distance are paramount factors in the quest of achieving total removal of Simpson grade I, including the involved dura and bone. The posterior petrosal, transtentorial presigmoid approach offers a wide and shallow operative field.1-7 When the patient has hearing loss, extending the resection of the temporal bone provides unmatchable exposure facilitating safer and more complete tumor removal. This article demonstrates the removal of a sphenopetroclival meningioma through total petrosectomy with closing of the external auditory canal and preservation of the facial nerve in the Fallopian canal. A total resection of the tumor was achieved with long-term preservation of cranial nerve function. The surgical steps of total petrosectomy are shown, including the skin flap, combined middle and posterior fossa craniotomy, skeletonization of the sigmoid transverse sinus, radical mastoidectomy, dissection of the Fallopian canal, and drilling of the labyrinth, cochlea, and petrous apex for superb exposure.8 We demonstrate the intra-arachnoidal microsurgical dissection utilized for the radical resection of petroclival meningioma. This surgery performed in 1995 is a testament to the time-tested technique. The patient consented to the procedure and image use. Images at 1:33 and 3:57 © Ossama Al-Mefty, used with permission.

Experience With the Endoscopic Contralateral Transmaxillary Approach to the Petroclival Skull Base.

OBJECTIVES/HYPOTHESIS: The contralateral transmaxillary (CTM) approach is a new surgical approach that improves the surgical trajectory relative to the petrous segment of the internal carotid artery (ICA). Here, we present our clinical experience with the CTM approach to the petroclival region of the skull base. STUDY DESIGN: Retrospective review. METHODS: A retrospective review of 29 patients who underwent a CTM approach for skull base pathology from 2015 to 2020 was performed. Assessment of gross total resection (GTR) was based on postoperative imaging. RESULTS: The male:female ratio was 15:14, with an average age of 52 years (range = 19-78 years). Diagnoses included: 12 chondrosarcomas, 11 chordomas, two meningiomas, one schwannoma, one metastasis, one petrous apicitis, and one arachnoid cyst. CTM was performed in addition to a transclival approach and ipsilateral transpterygoid approach in all patients. Reconstruction of surgical defects included a vascularized flap in all but two patients: 24 nasoseptal flaps and three lateral nasal wall flaps. The reconstructive flap was on the same side as the CTM approach in 22 of 28 (79%) patients. There were no ICA injuries. In a subset of patients with chondromatous tumors, GTR of the targeted area was achieved in 16 of 22 (73%) evaluable chondromatous tumors. With a median follow-up of 13 months, 64% of these patients are without disease or dead of other causes; the remainder are alive with disease. CONCLUSIONS: The CTM approach improves the degree of resection of skull base tumors involving the petroclival region using an endoscopic endonasal approach and may minimize risk to the ICA. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:294-298, 2021.

Anterior Transpetrosal Approach and Microsurgical Resection of a Petrous Tentorial Meningioma: 3-Dimensional Operative Video.

Tentorial meningiomas are challenging tumors because of its complex relationship with vital neurovascular structures. We present the case of a 41-yr-old female with a history of right-sided facial numbness associated with pain around the ear. Magnetic resonance imaging demonstrated a lesion in the right tentorium edge closely related with the porus trigeminus, suggestive of a meningioma. Because of worsening of symptoms the patient underwent surgery for tumor removal. A standard temporo-zygomatic craniotomy was performed, followed by an extradural peeling of the middle fossa; the petrous apex was drilled allowing access to the posterior fossa dura. Dural opening was carried connecting the temporal and posterior fossa, and the tentorium was then cut to the incisura. The tumor was identified and completely removed reaching Simpson grade I resection. Postoperatively, the patient presented a right dry eye in the first days that fully improved, and also a right-sided facial paralysis (House-Brackmann grade IV) and diplopia, both recovered completely after 4 mo. We believe that facial paralysis was the result of an undesired traction of the geniculate ganglion, or upon the nerve itself. To avoid such complication, dissection over the GSPN must be carried parallel to that nerve. Facial numbness and pain improved with no neurological other deficits. Tentorial meningiomas are complex deep-seated lesions that can be successfully approached through an anterior transpetrosal route in selected cases. Informed consent was obtained from the patient for publication of this operative video. Anatomical images were a courtesy of the Rhoton Collection, American Association of Neurological Surgeons/Neurosurgical Research and Education Foundation.

Síndrome de Eagle: relato de caso / Eagle Syndrome: a case report

A síndrome de Eagle é uma condição rara e com etiologia ainda não bem estabelecida, a qual se deve ter bastante suspeição para seu correto tratamento. Seu tratamento deve ser definido em conjunto com o paciente, seja ele conservador ou cirúrgico, sempre levando em consideração as expectativas do paciente, além da maior expertise do profissional na modalidade escolhida para o tratamento. Neste artigo, apresentamos uma paciente de 35 anos atendida no Hospital Felício Rocho, discutindo os diversos aspectos da doença, inclusive a modalidade de tratamento escolhida para o caso.

Eagle syndrome is a rare condition, and its etiology has not yet been well established and its correct treatment is uncertain. Its treatment must be defined together with the patient, be it conservative or surgical, always taking into consideration the patient's expectations, in addition to a solid professional expertise in the modality chosen for the treatment. In this article, we present the case of a 35-year-old patient who was admitted to the Felício Rocho Hospital and discuss the various aspects of the disease, including the treatment modality chosen for the case.

Active middle ear implants in patients undergoing subtotal petrosectomy: long-term follow-up.

OBJECTIVE: In 2009, we had introduced the active middle ear implant (aMEI) round window coupling in patients undergoing a subtotal petrosectomy and reported our first results. In the current study, we evaluated the long-term firmness of the vibranting floating mass transducer (FMT) within the round window niche, the long-term audiologic results and the patient's perspective of wearing the speech processor over time. PATIENTS AND INTERVENTION: Of 10 patients, 6 female and 1 male patients (age range from 30 to 71 yr) had undergone subtotal petrosectomy with aMEI round window vibroplasty and were available for a long-term follow-up. Indications were recurrent or chronic ear infections with preserved inner ear function and inability for ossicular chain reconstruction. A thin piece of fascia was placed between the FMT and the round window membrane once the round window niche had been enlarged by drilling. The operative cavity was filled with fat and a muscle flap in all cases. MAIN OUTCOME MEASURES: Audiologic evaluations included pre- and postoperative pure-tone audiometry, Freiburger syllable and numeric tests. All patients underwent preoperative computed tomographic (CT) scans and magnetic resonance imaging (MRI) examination. Postoperative follow-up included CT scans at 1 and preferentially 3 to 5 years to confirm the correct positioning of the FMT and the complete removal of the underlaying pathology. Subjective benefit was rated by the Glasgow Hearing Aid Benefit Profile. RESULTS: There were no immediate postoperative complications. CT scans confirmed the correct and durable positioning of the FMT. Audiometric tests revealed a stable and adequate functional gain in all patients with limited adjustments over time. Subjective rating reached a high satisfaction score, and all patients remained long-term implant users. One patient developed a skin necrosis over the implant because of excessive pressure exerted by the retaining magnet of the headpiece. Revision was performed using local skin flaps with preservation of the functioning implant. CONCLUSION: Our radiologic, audiometric, and subjective data show stable long-term results of round window vibroplasty in patients undergoing subtotal petrosectomy, and we continue to recommend this treatment option instead of another mastoid revision procedure.

Petroclival meningiomas: surgical management and common complications.

Petroclival meningiomas are technically challenging lesions. They have a tendency to grow slowly, involve cranial nerves and compress the brainstem and basilar artery, pushing them to the opposite side. Their natural history is marked by clinical deterioration and fatal outcome. They were once considered inoperable lesions; decades ago, mortality rates were higher than 50%. The authors describe 15 petroclival meningiomas treated surgically between 1995 and 2007. The main approaches used were combined anterior petrosectomy and retrosigmoid (3 cases), retrosigmoid (8 cases), and pre-sigmoid and subtemporal (4 cases). The mortality rate was 13.5% due to surgical bed hematoma and brain ischemia. The post-operative complications were hydrocephalus in 2 cases, cerebrospinal fluid leak in 2 cases and infection of surgical flap in one case. Limiting factors for surgical removal are tumor consistency, encasement of brainstem perforators and pre-operative clinical status.

The suprapetrosal craniotomy.

OBJECTIVE: The primary aim of this study was to establish standard sites for bur holes that maintain constant anatomical relationships with the skull base and neural structures and can serve as the basal aspect of supratentorial temporooccipital craniotomies. METHODS: To determine cranial-cerebral relationships, the authors created bur holes in 16 adult cadaveric skulls. Three bur holes were made on each side of the skulls (32 cerebral hemispheres). The authors then introduced plastic catheters through the bur holes to evaluate pertinent cranial and neural landmarks. The first bur hole, located anterior to the auricle of the ear, appeared to have a particular anatomical relationship with the anterior aspect of the petrous portion of the temporal bone and the most anterior aspect of the midbrain. The second bur hole, whose base was located 1 cm above the interface of the parietomastoid and squamous sutures, had a particular relationship with the posterior border of the petrous portion of the temporal bone and with the posterior aspect of the midbrain. The third bur hole, whose base was located 1 cm above the asterion, was mostly supratentorial and particularly related to the preoccipital notch. CONCLUSIONS: The preauricular bur hole and the bur hole whose base was located 1 cm above the interface of the parietomastoid and squamous sutures delimit anteriorly and posteriorly the external projection of the petrous bone and the midbrain. The middle fossa floor is located anterior to the site of the preauricular bur hole, and the superior surface of the tentorium is posterior to the bur hole located above the parietomastoid-squamous suture interface. Together with the bur hole whose base is located above the asterion, these bur holes can be considered standards for temporooccipital craniotomies.

Accesos quirúrgicos a los meningeomas petroclivales: indicaciones, complicaciones y resultados / Surgical approaches for petroclival meningiomas: indications, complications and results

Introducción: Los meningeomas de la región petroclival son responsables de cerca del 13 por ciento de los meningeomas de la base del cráneo. El promedio de edad de los pacientes que los presentan es aproximadamente 45 años En la mayoría de los casos existe extensión a la región paraselar. Material y Métodos: Los autores realizan una revisión crítica de la literatura, presentando los posibles accesos quirúrgicos e sus indicaciones, efectividad e posibles complicaciones. Resultados: Los accesos quirúrgicos para la región petroclival pueden ser: petroso, vía petrosa combinada anterior y posterior, vía presigmoidea combinada supra e infratemporal, órbito-zigomático infratemporal, retrosigmoideo intradural, suprameatal, pterional, retromastoideo, subtemporal y vía combinada retromastoidea-subtemporal. Discusión y Conclusiones: Una valoración neuro-radiológica precisa que permita escoger un abordaje quirúrgico apropiado juntamente con avances en la técnica microquirúrgica y propuestas de nuevos accesos, son factores que han contribuido al progreso significativo en el tratamiento quirúrgico de los meningeomas petroclivales.

[Combined supra and infratentorial presigmoideo approach for lesions of the petrous and clival regions]. / Abordaje combinado suprainfratentorial presigmoideo en las lesiones de la región petrosa y clival.

INTRODUCTION: Petrous and petroclival lesions may be surgically treated with combinations of suprainfratentorial presigmoideo approach and microsurgical techniques. OBJECTIVE: To demonstrate the utility and to present our surgical experiences with this approach. PATIENTS AND METHODS: Thirteen patients with lesions of the clival, petrous region and of the cerebellopontine angle with extension toward the anterior portion of brainstem were taken to the operative room. There were nine women and four men. Eleven were adults and two children. The main clinical manifestations were headache (100%), dysfunction of cranial nerves (90%), ataxia (90%) hemiparesis (75%). There was papiledema in 45%. Petroclival meningiomas and schwannomas were the more frequent lesions. There were three patients with intraxial brainstem tumors and two arteriovenous malformations. There were not aneurysms. We performed nine retrolaberintic, three translaberintic and one transcochlear approach. RESULTS: There was not severe incapacity, vegetative or dead patients. The surgical complications were facial nerve paresis (31%), cerebrospinal fluid leak (23%), decreased gag reflex (15%), abducens nerve paresis, hemiparesis and Claude Bernard Horner syndrome (8%). 50% of these complications disappeared three months later. CONCLUSIONS: The suprainfratentorial presigmoidal approach and their surgical variations could be utilized to obtaining a low morbimortality, in the treatment of different neoplasm and vascular diseases of the petrous and petroclival region.

Petrous apex region. Surgical anatomy, lesions, and operative techniques.

The author describes the anatomy of the region of the petrous apex giving emphasis to the limits of surgical resection. The cochlea, located at the apex of the angle formed by the intersection of a line along the sphenopetrosal groove and a line from the facial hiatus to the internal auditory canal, has to be protected to preserve hearing. Surgical approaches can be divided in the posterior presigmoid approach that provides exposure to the posterior petrous bone and upper two thirds of the clivus, and the anterior subtemporal approach that provides exposure to the trigeminal ganglion, petrous carotid artery, Meckel's cave, and posterior cavernous sinus. Opening of Meckel's cave provides additional space for medial and inferior resection of the petrous apex. Two illustrative cases of primary petrous apex lesions are presented to demonstrate the surgical exposure obtained with each approach.

Petrous apex region. Surgical anatomy, lesions, and operative techniques

The author describes the anatomy of the region of the petrous apex giving emphasis to the limits of surgical resection. The cochlea, located at the apex of the angle formed by the intersection of a line along the sphenopetrosal groove and a line from the facial hiatus to the internal auditory canal, has to be protected to preserve hearing. Surgical approaches can be divided in the posterior presigmoid approach that provides exposure to the posterior petrous bone and upper two thirds of the clivus, and the anterior subtemporal approach that provides exposure to the trigeminal ganglion, petrous carotid artery, Meckel's cave, and posterior cavernous sinus. Opening of Meckel's cave provides additional space for medial and inferior resection of the petrous apex. Two illustrative cases of primary petrous apex lesions are presented to demonstrate the surgical exposure obtained with each approach

Avaliaçäo do acesso petroso para os meningeomas petroclivais / Evaluation of petrosal approach for the petroclival meningiomas

Foi realizado o estudo anatômico do acesso petroso, em ambos os lados, de 20 segmentos cefálicos e 10 crânios e analisados os resultados do tratamento cirúrgico através do acesso petroso de 10 pacientes com meningeoma petroclival. As dificuldades essenciais desse acesso estao relacionadas com a preservaçao dos seios venosos durais e da veia Labbé com a retraçao do lobo temporal e do hemisfério cerebelar. Algumas técnicas alternativas mostraram-se úteis na superaçao dessas dificuldades: 1) a realizaçao do acesso retrolabiríntico, antes da craniotomia, ajuda a prevenir a lesao dos seios venosos durais envolvidos; 2) a extensao da craniotomia nos sentidos têmporo-occipital e têmporo-anterior, respectivamente, permite diminuir a retraçao sobre o hemisfério cerebelar e o lobo temporal e possibilita um afastamento mais seguro do lobo temporal; 3) a realizaçao da tentoriotomia, sem retraçao do lobo temporal, evita a tensao demasiada sobre a veia de Labbé. O estudo anatômico e os resultados obtidos na presente casuística comprovam que o acesso petroso possibilita ampla via de abordagem à regiao petroclival, permitindo remoçao completa dos meningeomas petroclivais com mínima morbidade e mortalidade.

Evoluçäo do acesso petroso para os meningeomas petroclivais / Evolution of the petrosal approach for petroclival meningiomas

Os autores fazem ampla revisao dos acessos combinados que foram utilizados para abordar as lesoes petroclivais, desde a era de Cushing até os tempos atuais. A ressecçao dos miningeomas petroclivais representam grande desafio e sao considerados como o protótipo de uma lesao petroclival. A revisao da literatura revelou que houve correlaçao entre os acessos combinados e o período em que foram utilizados para abordar as lesoes petroclivais. O acesso petroso oferece uma ampla via à regiao petroclival, possibilitando uma remoçao completa dos meningeomas petroclivais com mínima morbidade e mortalidade. O acesso petroso representa o resultado final da associaçao de idéias pré-existentes descritas anteriormente.

Bases anatômicas do acesso petroso / Anatomical landmarks of petrosal approach

Sob técnica microcirúrgica, foram dissecadas 10 cabeças cadavéricas, permitindo o estudo de 20 regiöes petroclivais e as estruturas nervosas e vasculares envolvidas neste acesso. Medidas referentes a distâncias em milimetros entre o ângulo sinodural e a veia de Labbé e entre a origem e a emergência dos VII, VIII, IX, X e XI nervos cranianos, seus orifícios e envoltórios durais foram tomados antes e após "drilagem" do osso temporal. A veia de Labbé desemboca no seio transverso a uma distância segura do ângulo sinodural. No material estudado, a distância minima entre estes pontos foi de 11,0 mm. A distância média entre a emergência dos VII e VIII nervos cranianos e o meato acústico interno foi de 11,5 mm à direita e 11,8 mm à esquerda. Após "drilagem" do osso temporal, a distância média foi de 15,41 mm à direita e 16,0 mm à esquerda. Para os IX, X e XI nervos cranianos, a distância média foi de 11,92 mm à direita e 11,43 mm à esquerda antes da "drilagem", e 14,21 mm à direita e 15,37 mm à esquerda depois da "drilagem". Estes resultados confirmam o ganho em campo cirúrgico, através do acesso petroso a regiâo petroclival

Aneurisma gigante da carótida interna na porçäo petrosa / Giant aneurysm of the internal carotid in the petrous portion

Os autores relatam um caso de aneurisma gigante da carótida interna, porçäo petrosa, com expansäo intracraniana, em paciente de 55 anos com hipoestesia tátil e dolorosa no território de V2 e V3, paralisia completa do VI nervo e hipoacusia acentuada, todos à esquerda. Foi feita abordagem direta, com ressecçäo total do aneurisma, fechamento da carótida interna no pescoço, ligadura, tamponamento e extirpaçäo do aneurisma na regiäo petrosa, com evoluçäo satisfatória. A revisäo da literatura pertinente ao assunto mostrou tratar-se de patologia rara