Clinoidal Meningiomas Research Articles

Collision of pituitary neuroendocrine tumor and anterior clinoid meningioma treated with a two-stage minimally invasive surgical strategy: illustrative case.

The locations of pituitary neuroendocrine tumor (PitNET) and anterior clinoid meningioma (ACM) appear to be very close but essentially different, as the former is inside the sella turcica while the latter is in the intradural space. A collision tumor thus requires a specific treatment strategy but has been rarely reported. A 77-year-old woman presented with progressive visual impairment due to significant compression of the optic apparatus by a collision of PitNET and ACM. With a minimally invasive two-stage therapeutic strategy, the ACM was first resected using an endoscopic mini-pterional approach, then the PitNET was removed with an endoscopic transnasal approach 8 weeks later, leading to significant improvement in visual function. The authors' literature search identified only 2 documented cases of a similar collision. This case underscores the complexity of the decision-making process in the management of collision tumors and suggests the potential benefit of staged minimally invasive surgical interventions in preserving visual function. Further accumulation of cases is warranted for refining the treatment strategy. https://thejns.org/doi/10.3171/CASE24240.

Anterior clinoid meningiomas: surgical results and proposed scoring system to predict visual outcomes.

The authors report a single-surgeon experience with anterior clinoid meningiomas (ACMs) and propose a novel scoring system to predict visual outcomes based on preoperative risk factors. A cohort study of all ACMs that were surgically treated by a single surgeon between 2003 and 2021 was performed. Visual function was assessed by an ophthalmologist pre- and postoperatively. Based on the combination of visual fields and visual acuity, 4 visual grades were described. Favorable visual outcomes were defined as mild visual deficit or intact vision postoperatively. Unfavorable visual outcomes were defined as a severe or moderate visual deficit. Predictors of unfavorable visual outcomes were identified using multivariable logistic regression analysis. A scoring system was then created using the resulting β coefficient. A receiver operating characteristic curve analysis was performed to identify a cutoff point on the grading score for stratifying patients at risk for unfavorable visual outcomes. Fifty-two patients met all inclusion criteria. Twenty-five (48%) patients presented with intact vision, and 27 (51%) presented with some visual dysfunction. Postoperative favorable visual outcomes were achieved in 39 patients (75%). Among the 27 patients presenting with visual dysfunction, 14 (52%) experienced improvement after surgery. No new visual deficits were observed among the 25 patients with intact vision at baseline. Nine patients (17%) had a reversible complication. Multivariable analysis showed that severe preoperative visual deficit (OR 13.03, 95% CI 2.64-64.39; p = 0.002), radiographic evidence of optic nerve (ON) encasement (OR 4.20, 95% CI 1.06-16.61; p = 0.04), intraoperative evidence of ON invasion (OR 17.31, 95% CI 2.91-102.86; p = 0.002), an average ganglion cell layer thickness of ≤ 70 µm (OR 21.54, 95% CI 2.94-159.04; p = 0.003), and an average retinal nerve fiber layer thickness of ≤ 80 µm (OR 13.68, 95% CI 1.91-98.00; p = 0.009) were associated with unfavorable visual outcome. The predictive score included the following factors: abnormal optical coherence tomography (OCT) findings, radiographic evidence of ON encasement by the tumor, and severe preoperative visual deficit. A score ≥ 4 of 6 points was demonstrated to be the cutoff associated with unfavorable visual outcome, with a sensitivity of 80%, specificity of 88%, positive predictive value of 80%, negative predictive value of 88%, and area under the curve of 0.847 (95% CI 0.674-1.0; p = 0.003). The authors have designed a practical and novel scoring system to predict visual outcomes in patients with ACMs. This scoring system may guide preoperative discussions with patients and timely surgical intervention to yield optimal visual function outcomes. Although most patients have excellent neurosurgical outcomes, severe baseline visual deficits, ON encasement, and characteristic OCT abnormalities are associated with unfavorable visual function after ACM resection.

Exoscopic extradural anterior clinoidectomy.

Extradural anterior clinoidectomy is a resourceful technique to decompress the optic nerve as well as increase exposure of the parasellar region during extensive approaches. Despite requiring adjunctive epidural bone work, this technique allows safe optic nerve mobilization and early devascularization for anterior clinoidal meningioma resection. This 2D operative video describes right optic nerve decompression by extradural anterior clinoidectomy and subsequent resection of a right Al-Mefty type III clinoid meningioma under exoscope magnification. The patient was a 50-year-old woman with a 1-year history of right visual acuity impairment and papillary atrophy. The exoscope allows a 360° view around the anterior clinoid, improving maneuverability. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23118.

Double Trouble – An Anterior Clinoidal Meningioma with a Concurrent Right MCA Aneurysm

Although meningiomas and cerebral aneurysms are common intracranial pathologies, their coexistence in one patient is rare. We present a case of right anterior clinoid meningioma that has a concurrent right middle cerebral artery (MCA) aneurysm. A 55-year-old female complaining of right-sided visual loss was admitted to our department after magnetic resonance imaging (MRI) revealed a right anterior clinoid meningioma that was extending to sella turcica and expanded superiorly, compressing the optic chiasm. With a plan of transnasal transsphenoidal endoscopic excision, a preoperative computed tomography angiogram was obtained, per our protocol. This revealed an incidental 3 mm right MCA bifurcation aneurysm. Due to the possibility of postoperative aneurysm bleeding, the patient was operated on with a right-sided pterional craniotomy. After 5 days of postoperative follow-up, the patient was discharged without complications. The histopathological analysis confirmed the diagnosis of psammomatous meningioma. This case underlines the importance of preoperative planning and being vigilant for incidental findings that might cause fatal consequences.

Endonasal, supraorbital, and transorbital approaches: minimal access endoscope-assisted surgical approaches for meningiomas in the anterior and middle cranial fossae.

Minimally invasive endoscope-assisted approaches to the anterior skull base offer an alternative to traditional open craniotomies. Given the restrictive operative corridor, appropriate case selection is critical for success. In this paper, the authors present the results of three different minimal access approaches to meningiomas of the anterior and middle fossae and examine the differences in the target areas considered appropriate for each approach, as well as the outcomes, to determine whether the surgical goals were achieved. A consecutive series of the endoscopic endonasal approach (EEA), supraorbital approach (SOA), or transorbital approach (TOA) for newly diagnosed meningiomas of the anterior and middle fossa skull base between 2007 and 2022 were examined. Probabilistic heat maps were created to display the distribution of tumor volumes for each approach. Gross-total resection (GTR), extent of resection, visual and olfactory outcomes, and postoperative complications were assessed. Of 525 patients who had meningioma resection, 88 (16.7%) were included in this study. EEA was performed for planum sphenoidale and tuberculum sellae meningiomas (n = 44), SOA for olfactory groove and anterior clinoid meningiomas (n = 36), and TOA for spheno-orbital and middle fossa meningiomas (n = 8). The largest tumors were treated using SOA (mean volume 28 ± 29 cm3), followed by TOA (mean volume 10 ± 10 cm3) and EEA (mean volume 9 ± 8 cm3) (p = 0.024). Most cases (91%) were WHO grade I. GTR was achieved in 84% of patients (n = 74), which was similar to the rates for EEA (84%) and SOA (92%), but lower than that for TOA (50%) (p = 0.002), the latter attributable to spheno-orbital (GTR: 33%) not middle fossa (GTR: 100%) tumors. There were 7 (8%) CSF leaks: 5 (11%) from EEA, 1 (3%) from SOA, and 1 (13%) from TOA (p = 0.326). All resolved with lumbar drainage except for 1 EEA leak that required a reoperation. Minimally invasive approaches for anterior and middle fossa skull base meningiomas require careful case selection. GTR rates are equally high for all approaches except for spheno-orbital meningiomas, where alleviation of proptosis and not GTR is the primary goal of surgery. New anosmia was most common after EEA.

Prognostic Factors in the Surgery of Clinoidal Meningiomas.

Clinoidal meningiomas are currently among the intracranial meningiomas with the greatest neurosurgical complexity, morbidity,and mortality associated with their resection. The worldwide literature has described tumor size (>4 cm3), patient age (>60 years), and invasion of the cavernous sinus as factors associated with a worse clinical outcome following surgery. We describe the series of cases of patients with clinoidal meningiomas who underwent microsurgical resection at our institution between January 2014 and March 2019. The intention was to analyze the multiple preoperative variables, such as the patient's demographic, tumor, and surgical characteristics, such as the Al-Mefty Classification to find a relationship with the patient's clinical outcome during their postoperative follow-up. Results: Death occurred in 4.8% of the cases. Postoperative morbidity was documented in 42.9%, the most frequent being ophthalmoparesis, followed by worsening of visual acuity, and new onset motor deficits. Radiological characteristics were assessed based on preoperative MRI. The maximum diameter, midline shift, invasion of the cavernous sinus, arterial encasement, and peritumoral edema were evaluated. Average intraoperative bleeding was 1.3 L. The most frequent histological grade was World Health Organization (WHO) grade 1 in 85.6% of the cases. Complete resection was obtained in 52.4% of the cases; 42.8% received fractionated stereotactic radiotherapy after surgery for disease control, and one received radiosurgery. Recurrence occurred in 33.3%. The average follow-up in months was 23.8. Conclusions:Demographic factors and tumor characteristics in clinoidal meningioma surgery are related to the subtype of meningioma according to the Al-Mefty Classification and impact directly the degree of resection, progression of the disease, and degree of postoperative complications. To achieve maximal resection while minimizing morbidity and mortality, these factors must be considered to decide on an appropriate approach and specific plan for each case.

The factors influencing postoperative efficacy of anterior clinoidal meningioma treatment and an analysis of best-suited surgical strategies.

To explore the influence of the type of anterior clinoidal meningioma on surgical strategy planning, surgical approach selection, and postoperative efficacy. We conducted a retrospective analysis of the clinical data of 63 cases, including data on visual function, extent of tumor resection, and postoperative follow-up. Grade I and II approaches were selected according to the type of tumor. A univariate analysis of the factors influencing the extent of tumor resection, postoperative visual function, and postoperative relapse and complications was conducted. Simpson Grade I-II total resection was seen in 48 cases (76.2%), with an overall relapse/progression rate of 12.7%. The tumor type and texture and the relationship between the tumors and adjacent structures were the main factors influencing total tumor resection (P < 0.01). The overall postoperative visual acuity improvement, stabilization rate, and deterioration rate were 76.2, 15.9, and 7.9%, respectively. Postoperative visual acuity level was significantly correlated with preoperative visual acuity level and tumor type (P < 0.01). Determining the type of tumor at a preoperative level and whether the optic canal and cavernous sinus are invaded can aid in the planning of detailed individualized surgical strategies.

How I do it: a purely endoscopic endonasal approach for anterior clinoidal meningioma.

Surgery for anterior clinoid meningiomas (ACMs) remains challenging due to their tight adhesion to vital neurovascular and has been traditionally performed through a transcranial approach. We present the key steps of the endoscopic endonasal approach (EEA) for ACMs with a video illustration and figures. The relevant surgical anatomy is described along with the indications and limitations of this approach. The EEA offers a good treatment option for selected ACMs. It allows for the removal of involved hyperostotic bone and dural attachments, early identification and control of the neurovascular structure, and avoidance of brain retraction.

Factors associated with favorable visual outcome after surgery of clinoidal meningiomas

BackgroundThe anatomical relationship between clinoidal meningiomas and the optic nerve accounts for their frequent finding on visual disturbances. The goal of the surgery is to perform complete resection and obtain visual recovery. The aim of this study is to determine the factors associated with favorable visual outcome. MethodsWe recorded clinical (including ophthalmological), imaging and surgical data of all patients operated on for clinoidal meningiomas between 2010 and 2020 in 2 French neurosurgical departments and we analyzed their impact on visual outcome. ResultsA total of 34 patients were included. At 3–4 months after surgery, 23 patients (68%) had favorable visual outcome. Factors associated with favorable visual outcome were duration of ophthalmologic symptoms < 6 months, preoperative visual acuity > 0.5, absence of optic atrophy, meningioma in high signal intensity on T2-weighted or FLAIR MRI, absence of optic canal involvement and absence of bone hyperostosis on pre-operative CT scan. A soft tumor and a clear brain/tumor border were intra-operative factor associated with favorable ophthalmological outcome. ConclusionsIn clinoidal meningiomas, an early surgery should be performed to optimize visual improvement. Hyperintense lesion on T2-weighted/FLAIR preoperative MRI is correlated with a soft consistency which allows an easier surgery associated with a favorable visual outcome. Invasion of the optic canal and bone hyperostosis should reserve the visual prognosis.

Extradural Clinoidectomy in Clinoidal Meningiomas: Analysis of the Surgical Technique and Evaluation of the Clinical Outcome.

The surgical treatment of clinoidal meningiomas is currently still discussed in the literature. Different surgical approaches have been proposed and evaluated, in multiple studies, in order to improve the surgical outcomes. The aim of this study is to evaluate the advantages of extradural clinoidectomy in the context of tumor removal radicality for visual function improvement. A retrospective analysis was performed on 74 patients—of which 26 patients with clinoidal meningiomas were in group III, according to Al Mefty classification—who underwent surgery at the Policlinico Umberto I Hospital between 2000 and 2019. Further, extradural clinoidectomy was performed on 15 patients (Group A), and 11 patients underwent the pterional approach only (Group B). Additionally, visual impairment was present in all 26 patients before surgery. Next, visual function assessment was performed on all patients, both in presurgery and postsurgery. Radiological follow up was performed at 3 and 6 months, and then every 12 months. Gross Total Resection (GTR) was achieved in 13/15 (86.7%) patients who underwent clinoidectomy, and in 4/11 (36.4%) patients who did not undergo clinoidectomy. Visual function improvement was achieved in 12/15 (80%) patients who underwent clinoidectomy and in 4 of 11 (36.4%) who did not undergo clinoidectomy. According to our study, extradural clinoidectomy is the most suitable method for facilitating the gross total resection of clinoidal meningiomas. Our experience and data suggest that a higher rate of total resection and, subsequently, the best visual outcomes are achieved. Extradural drilling via the anterior clinoid process reveals a wider surgical corridor for meticulous tumor resection.

Extended endoscopic transorbital approach with superior-lateral orbital rim osteotomy: cadaveric feasibility study and clinical implications (SevEN-007).

The endoscopic transorbital approach (ETOA) has been developed, permitting a new surgical corridor. Due to the vertical limitation of the ETOA, some lesions of the anterior cranial fossa are difficult to access. The ETOA with superior-lateral orbital rim (SLOR) osteotomy can achieve surgical freedom of vertical as well as horizontal movement. The purpose of this study was to confirm the feasibility of the ETOA with SLOR osteotomy. Anatomical dissections were performed in 5 cadaveric heads with a neuroendoscope and neuronavigation system. ETOA with SLOR osteotomy was performed on one side of the head, and ETOA with lateral orbital rim (LOR) osteotomy was performed on the other side. After analysis of the results of the cadaveric study, the ETOA with SLOR osteotomy was applied in 6 clinical cases. The horizontal and vertical movement range through ETOA with SLOR osteotomy (43.8° ± 7.49° and 36.1° ± 3.32°, respectively) was improved over ETOA with LOR osteotomy (31.8° ± 5.49° and 23.3° ± 1.34°, respectively) (p < 0.01). Surgical freedom through ETOA with SLOR osteotomy (6025.1 ± 220.1 mm3) was increased relative to ETOA with LOR osteotomy (4191.3 ± 57.2 mm3) (p < 0.01); these values are expressed as the mean ± SD. Access levels of ETOA with SLOR osteotomy were comfortable, including anterior skull base lesion and superior orbital area. The view range of the endoscope for anterior skull base lesions was increased through ETOA with SLOR osteotomy. After SLOR osteotomy, the space for moving surgical instruments and the endoscope was widened. Anterior clinoidectomy could be achieved successfully using ETOA with SLOR osteotomy. The authors performed ETOA with SLOR osteotomy in 6 cases of brain tumor. In all 6 cases, complete removal of the tumor was successfully accomplished. In the 3 cases of anterior clinoidal meningioma, anterior clinoidectomy was performed easily and safely, and manipulation of the extended dural margin and origin dura mater was possible. There was no complication related to this approach. The authors evaluated the clinical feasibility of ETOA with SLOR osteotomy based on a cadaveric study. ETOA with SLOR osteotomy could be applied to more diverse disease groups that do not permit conventional ETOA or to cases in which surgical application is challenging. ETOA with SLOR osteotomy might serve as an opportunity to broaden the indication for the ETOA.

Surgery for clinoidal meningiomas with cavernous sinus extension: Near-total excision and chiasmopexy

BackgroundThe main factors limiting the extent of resection for clinoidal meningiomas are cavernous sinus extension and vessel adventitia involvement. The proximity to the optic apparatus and the risk of radiation-induced optic neuropathy often prevents many surgeons from proposing adjuvant radiosurgery.MethodWe describe a simple technical solution that is to place a fat graft between the optic apparatus and the residual tumor to maintain the distance gained at surgery and facilitates the identification of anatomic structures.ConclusionThis technique allows to deliver optimal therapeutic doses to the residue reduces the dose received by the optic nerve below 8 Gy.

Microscope-Based Augmented Reality with Intraoperative Computed Tomography-Based Navigation for Resection of Skull Base Meningiomas in Consecutive Series of 39 Patients.

Simple SummaryThe aim of surgery for skull base meningiomas is maximal resection with minimal damage to the involved cranial nerves and cerebral vessels. Compared to non-skull base meningiomas, these lesions show a reduced rate of gross total resection (GTR). Therefore, the use of technologies for improved orientation in the surgical field, such as neuronavigation and augmented reality (AR), is of interest. We confirmed in a consecutive series of 39 patients who underwent surgery for skull base meningiomas that automatic registration with intraoperative computed tomography (iCT) showed high registration accuracy and that microscope-based AR largely facilitated the resection by increasing surgical precision and providing improved intraoperative orientation by visualizing the tumor and the critical neurovascular structures in the operative microscope. No injuries to critical neurovascular structures occurred. There were 26 patients (66.6%) who underwent GTR. Additionally, 33 out of 35 patients who lived to follow-up could ambulate.Background: The aim of surgery for skull base meningiomas is maximal resection with minimal damage to the involved cranial nerves and cerebral vessels; thus, implementation of technologies for improved orientation in the surgical field, such as neuronavigation and augmented reality (AR), is of interest. Methods: Included in the study were 39 consecutive patients (13 male, 26 female, mean age 64.08 ± 13.5 years) who underwent surgery for skull base meningiomas using microscope-based AR and automatic patient registration using intraoperative computed tomography (iCT). Results: Most common were olfactory meningiomas (6), cavernous sinus (6) and clinoidal (6) meningiomas, meningiomas of the medial (5) and lateral (5) sphenoid wing and meningiomas of the sphenoidal plane (5), followed by suprasellar (4), falcine (1) and middle fossa (1) meningiomas. There were 26 patients (66.6%) who underwent gross total resection (GTR) of the meningioma. Automatic registration applying iCT resulted in high accuracy (target registration error, 0.82 ± 0.37 mm). The effective radiation dose of the registration iCT scans was 0.58 ± 1.05 mSv. AR facilitated orientation in the resection of skull base meningiomas with encasement of cerebral vessels and compression of the optic chiasm, as well as in reoperations, increasing surgeon comfort. No injuries to critical neurovascular structures occurred. Out of 35 patients who lived to follow-up, 33 could ambulate at their last presentation. Conclusion: A microscope-based AR facilitates surgical orientation for resection of skull base meningiomas. Registration accuracy is very high using automatic registration with intraoperative imaging.

Modified intradural anterior clinoidectomy to protect the paraclinoid neurovascular structures: A technical note

ObjectiveAnterior clinoidectomy is effective in creating an adequate working field during surgery for paraclinoid lesions. However, intradural anterior clinoidectomy (iAC) is associated with intraoperative injury to the paraclinoid neurovasular structures because they are exposed in the surgical field. Here we introduce our modified technique in removing the anterior clinoid process (ACP) to compensate the drawbacks of iAC. MethodsThis technical case report is presented by demonstration of cadaver dissection and surgical video. ResultsCadaver dissection study demonstrates the step-by-step procedure. Our technique primarily aims at sectioning of the dura adjacent to the ACP to obtain both intradural and extradural operative fields. With this technique, the ACP can be safely removed without injuring the neurovascular structure, such as the optic nerve and internal carotid artery. As an example of its clinical application, we present a case of a 67-year-old woman with anterior clinoid meningioma and visual deficits. The ACP was safely removed using a high-speed drill without injuring the neurovascular structures. Gross total resection was achieved. Her vision returned to normal postoperatively. ConclusionsUsing our modified technique, the widely reflected dura covers the critical neurovascular structure during the skull base drilling. Therefore, this technique compensates the drawbacks inherent to iAC.

Posterior Clinoid Meningioma-A Formidable Entity: 2-Dimensional Operative Video.

Meningiomas originating from the posterior clinoid process are the rarest form of meningioma making up less than 1% of skull base meningiomas.1 These tumors have notoriously poor outcomes characterized by incomplete resections and a litany of complications.1 Owing to their scarcity and frequent confusion with meningiomas arising from adjacent skull base regions, the surgical anatomy, technical nuances, and potential pitfalls are not well addressed in modern literature. The most challenging aspect of the resection occurs while dissecting tumor in the retrosellar space.2 Meningiomas of neighboring regions such as those of the tuberculum, anterior clinoid process, or petrous apex, all arise from above the membrane of Liliequist which provides a plane of tumor dissection from the neurovascular structures of the posterior fossa. Posterior clinoid meningiomas arise from beneath this arachnoidal membrane and thus lack its protection while dissecting tumor from the basilar artery and its perforators.3,4 Surgical resection of these tumors requires meticulous intra-arachnoidal dissection of the encased basilar artery and its branches, and separation of tumor from the hypothalamus, cranial nerves, pituitary stalk, and brainstem while preserving their vascular supply. The combined petrosal facilitates a wide exposure reaching the entire central skull base for the safe visualization and dissection of tumor along the length of the basilar and the hypothalamus.5,6 The patient is a 68-year-old woman with hemiparesis and seizures from a posterior clinoid meningioma. The tumor was resected using the combined petrosal approach. The patient has consented to surgery and publication of images. {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"VIDEO.","caption":"","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_279na25v"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]}

Treatment and Pathophysiology of Clinoidal Meningiomas

Treatment and Pathophysiology of Clinoidal Meningiomas

Intraoperative use of heads-up display in skull base surgery.

In this video, the authors highlight the applications of virtual reality and heads-up display in skull base surgery by presenting the case of a 45-year-old woman with an incidental large clinoid meningioma extending into the posterior fossa. The patient underwent preoperative endovascular tumor embolization to facilitate tumor resection and reduce blood loss, followed by a right pterional craniotomy. The use of intraoperative Doppler, intraoperative neurophysiological monitoring, and endoscope-assisted microsurgery is also featured. A subtotal resection was planned given tumor encasement of the posterior communicating and anterior choroidal arteries. No new neurological deficits were noted after the surgical procedure.The video can be found here: https://stream.cadmore.media/r10.3171/2021.10.FOCVID21177

Individualized Cerebral Artery Protection Strategies for the Surgical Treatment of Parasellar Meningiomas on the Basis of Preoperative Imaging.

ObjectiveParasellar meningiomas (PMs) represent a cohort of skull base tumors that are localized in the parasellar region. PMs tend to compress, encase, or even invade the cerebral arteries and their perforating branches. The surgical resection of PMs without damaging neurovascular structures is challenging. This study aimed to analyze functional outcomes in a series of patients who underwent surgery with individualized cerebral artery protection strategies based on preoperative imaging.MethodsA retrospective review was performed on a single surgeon’s experience of the microsurgical removal of PMs in 163 patients between January 2012 and March 2020. Individualized approaches with a bidirectional dissection strategy were used. Cerebral artery invasion classification, neurological outcomes, MRC Scale for muscle strength, and Karnofsky performance scale were used to assess tumor vascular invasion, functional outcome, and patient quality-of-life outcomes, respectively.ResultsTotal resection (Simpson grade I or II) was achieved in 114 patients (69.9%) in our study. A total of 44.7% of patients had improved vision at consecutive follow-ups, 51.1% were stable, and 3.8% deteriorated. Improvements in cranial nerves III, IV, and VI were observed in 41.1%, 36.2%, and 44.8% of patients, respectively. The mean follow-up time was (38.8 ± 27.9) months, and the KPS at the last follow-up was 89.6 ± 8.5. Recurrence was observed in eight patients (13.8%) with cavernous sinus meningiomas, and the recurrence rates in anterior clinoid meningiomas and medial sphenoid wing meningiomas were 3.8% and 2.8%, respectively.ConclusionsPreoperative imaging is important in the selection of surgical approaches. Maximum tumor resection and cerebral artery protection can be achieved concurrently by utilizing the bidirectional dissection technique. Individualized cerebral artery protection strategies provide great utility in improving a patient’s quality of life.

Complete Removal of Bilateral Clinoidal Meningiomas Through a Pterional Approach: 3-Dimensional Operative Video

Abstract Surgical removal of anterior clinoidal meningiomas remains a challenge because of its complicated relationship with surrounding vascular and neural structures. 1-3 This is a 39-yr-old female, with headaches, neurofibromatosis type 2, and history of 3 previous brain surgeries. The patient gave the consent to use the images and surgical video. In the imaging control, the growth of bilateral anterior clinoidal meningiomas was observed. A right pterional approach and extradural anterior clinoidectomy was performed, and a complete resection of bilateral clinoidal meningiomas was achieved obtaining a Simpson scale resection grade 1. The patient evolved without neurological deficits after the surgery, and the postoperative magnetic resonance imaging (MRI) evidenced a complete bilateral resection of the clinoidal meningiomas. Clinoidal meningiomas are the unique subset of tumors because of their close proximity to neurovascular structures and can be safely excised with minimal morbidity and mortality using microsurgical techniques. 3-5 In rare cases of bilateral anterior clinoidal meningiomas such as the case presented, we recommend detailed neuroimaging analysis and consider the possibility to resect both in a single approach.

Simpson Grade I Resection of Type II Clinoidal Meningioma Through Cranio-orbital Zygomatic Approach: 2-Dimensional Operative Video.

Clinoidal meningiomas have been considered as a separate entity with distinguishing clinical, radiological, and surgical considerations.1-2 Surgical mortality and morbidity associated with anterior clinoidal meningiomas has remained high in the past, with radical resection considered unattainable.3 However, the extent of surgical removal is clearly the most determining factor in tumor recurrence and progression. Clinoidal meningiomas have been classified into 3 types according to their origin from the dura surface of the anterior clinoid and subsequent arachnoidal rearrangement around the parasellar neurovascular structures.1 In type II, there is an arachnoidal plane that allows the tumor dissection from the encased carotid artery and its branches and the optic nerve. In this type, the involvement of the cavernous sinus is limited to the external wall, which can also be removed. Hence, these tumors are amenable to Simpson grade I resection (tumor, dura, and bone). Approaching through the multidirectional axis provided by the cranio-orbital zygomatic approach allows safe exposure of the tumor and vascular control.4-5 Proximal carotid control is obtained in the petrous carotid canal, the invaded anterior clinoid is removed by and large extradurally, and the Sylvian fissure is split wide open to establish dissecting planes with the middle cerebral artery branches. The optic canal is opened, and tumor extension is removed.6 The invaded outer wall of the cavernous sinus and superior orbital fissure is removed. We demonstrate this technique in a 48-yr-old patient who consented for surgery and publication of images. All images at 2:27, center and right images at 2:46, and all images at 2:58, reused with permission from LWW, from Al-Mefty, Operative Atlas of Meningiomas. Left image at 2:46 reprinted from Surg Neurol, Vol 60/issue 6, Arnautović KI, Al-Mefty O, Angtuaco E, A combined microsurgical skull-base and endovascular approach to giant and large paraclinoid aneurysms, pp. 504-520, Copyright 1998, with permission from Elsevier. Image at 8:21 reprinted from Al-Mefty,1 Clinoidal meningiomas, by permission from JNSPG.