Resection of a Sphenoid Wing Meningioma
Main Text
Sphenoid wing meningiomas are typically benign, slow-growing tumors that may be identified incidentally on imaging or due to a symptomatic presentation from compression of a nearby structure. Located along the sphenoid wing, these tumors may infiltrate or compress the optic nerve, oculomotor nerve, cavernous sinus, or internal carotid artery, causing neurologic deficits such as visual disturbances, headache, paresis, and diplopia. Surgical resection is considered the first-line treatment for a symptomatic meningioma, but is often challenging due to tumor proximity to these critical neurovascular structures. The most important prognostic factor for recurrence is the completeness of the surgical removal of the tumor, but this goal must be adapted to preserve neurologic function based on individual tumor location and invasion. Here we present a case of a 43-year-old patient diagnosed with a sphenoid wing meningioma after presenting with episodic difficulty speaking and aura-like symptoms who underwent total neurosurgical resection of the tumor via craniotomy.
Meningioma; sphenoid wing; surgical management; skull base tumors; craniotomy.
Meningiomas are the most common benign brain tumors and account for approximately 20% of all primary intracranial tumors.1,2 Around 15–20% of meningiomas originate from the sphenoid wing, and meningiomas are also the most common tumors of this region.2,3 They are typically slow-growing tumors that arise from arachnoid cap cells found between the brain and skull, along the spinal cord, and within the ventricles.1,5 They are most commonly found in middle-aged individuals but can occur at any age, and are often identified incidentally on imaging. Only about 25% of meningiomas are symptomatic, resulting from compression of a nearby structure.1
Sphenoid wing meningiomas are typically classified both by morphology and location. Morphology criteria by the World Health Organization categorizes meningiomas into three groups: grade I is benign, grade II is borderline, and grade III is malignant. 90% of meningiomas are grade I, and less than 3% are grade III.2,5 Sphenoid wing meningiomas are also often classified based on their location along the sphenoid wing, either lateral, medial, or spheno-orbital (en plaque).3 En plaque meningiomas are sheet-like lesions that infiltrate the dura and sometimes invade the adjacent bone.3,6 These criteria are used to guide treatment selection, and location categorization is often associated with the presenting symptoms. Treatment strategies for meningiomas include observation, radiation alone, or surgical resection with or without radiation. Surgical resection of sphenoid wing meningiomas is typically the main curative approach but is challenging due to its proximity to critical neurovascular structures, including but not limited to the optic nerve, oculomotor nerve, and internal carotid artery.3,5 Here we discuss a case of a left-sided sphenoid wing meningioma treated by neurosurgical resection via craniotomy.
This is a 43-year-old patient that presented with episodes of speech arrest and aura-like symptoms for 4 weeks. Other symptoms may have included visual impairment, orbital pain, headaches, mental status changes, paresis, or other cranial neuropathies depending on the extent of tumor invasion and areas of compression.1,3,4
Physical exam findings may include visual field deficits, dysphasia, or other neurologic abnormalities depending on the structures affected by the tumor.3 In addition to a thorough history and physical exam with attention to the symptoms listed above, MRI is indicated for diagnosis and tumor identification. This patient underwent MRI, which showed the presence of a left-sided sphenoid wing meningioma. If surgery is indicated, CT may be used to determine if the tumor is invading the bone and to help navigate the tumor area during surgery.3
Treatment for sphenoid wing meningiomas often depends on symptomatology, size, location, and presence of bone invasion. In general, neurosurgical resection is the mainstay of treatment for symptomatic sphenoid wing meningiomas.3 If small, asymptomatic tumors are found incidentally on imaging, observation may be considered. Meningiomas are generally slow-growing tumors, and watchful waiting may be employed for patients who prefer to defer treatment. Perifocal edema observed on MRI is a key indicator of pial invasion, which serves as an indication for surgery and typically as a contraindication for radiation therapy.
In addition, if the tumor is only causing ocular symptoms, such as visual failure through compression of the optic nerve, alternative procedures may be indicated to relieve the compression. For example, endoscopic transnasal orbital decompression has been used to successfully relieve optic neuropathy.4 This option is less invasive than full neurosurgical resection but is not curative and requires continuous monitoring for potential tumor growth.
Meningiomas have also been treated with radiotherapy techniques, including stereotactic radiosurgery, which involves the delivery of large single doses of radiation to the target in the hopes of reducing tumor size.7,8 Stereotactic radiosurgery is considered as an option for small, asymptomatic tumors, but the proximity of the sphenoid wing to highly radiosensitive structures like the optic nerves often prohibits its use for meningiomas in this location.3
Goals of treatment for symptomatic sphenoid wing meningiomas include the resolution of associated symptoms and improvement of quality of life. Full surgical resection of the tumor is a curative treatment option that aims to eliminate the source of symptom development and prevent any further progression.3,5 As described above, other surgical approaches may be less invasive with a focus on symptomatic relief, but they may not be curative.
Contraindications to surgical resection of sphenoid wing meningiomas are often related to the extent of tumor invasion into the central nervous system, cavernous sinus, orbits, or internal carotid artery. While the vast majority of sphenoid wing meningiomas are benign, a malignant tumor may present with more aggressive invasion of these local structures.9
Here we present the case of a 43-year-old patient with a left-sided sphenoid wing meningioma. The patient was experiencing episodes of difficulty speaking and aura-like disturbances, and therefore elected to undergo surgical resection of the tumor. The tumor was exposed using a pterional, or frontotemporal, craniotomy. Microsurgical techniques were used to locate tumor borders, devascularize, and remove the tumor. A wire mesh was inserted to line the residual cavity in the brain, and the bone flap was refixed to the skull to close the craniotomy. Overall, the procedure went very well without any complications. We followed the 4D concept, which involves devascularization, detachment, debulking, and dissection.
Surgery is the first-line treatment for symptomatic sphenoid wing meningiomas.3,10 The goal of this operation should always be the total resection of the meningioma at first surgery, while also preserving surrounding neurovascular structures and their function.10,11 The indication for surgery should always be tailored to the specific patient based on their age, extent of tumor involvement, tumor behavior over time, and neurologic status. The most important prognostic factor for disease recurrence is the completeness of the surgical removal of the tumor; therefore, this is the chief objective.10–13
The Simpson scale is used to predict the risk of meningioma recurrence following tumor resection.3,10,12 This operation completed a Simpson grade 2 resection, which indicates complete tumor resection with coagulation of dural attachment. This predicts a 10-year tumor recurrence of 19%. For the total removal of the tumor, including the site of attachment, or Simpson grade 1, there is an estimated 9% recurrence.3,10 The goal of surgery is to achieve a Simpson grade 1 or 2 resection with total removal of the tumor in order to minimize the risk of recurrence. Grade 3 resection is a complete resection but without dural coagulation and raises the recurrence risk to 29%. Grade 4 is subtotal resection with a 10-year recurrence predicted at 40%.3 If the tumor does recur, it is likely to be within 5 years of surgery.10
The sphenoid wing extends from the anterior clinoid process to the pterion, and sphenoid wing meningiomas may develop anywhere across this area. Sphenoid wing meningiomas are often categorized based on their location along the sphenoid wing as each group raises specific surgical problems. Cushing and Eisenhardt were the first to create a system to classify meningiomas in this way, and numerous modifications have been made over time in order to better understand the natural history, and predict outcomes and recurrence.2,11,14,15
Lateral and middle sphenoid wing meningiomas are generally more accessible during surgery. Therefore, they are easier to resect; however, they pose a challenge following surgery since they commonly involve the bone, which leads to increased rates of recurrence.10 At the other end, medial sphenoid wing meningiomas often present as more challenging to resect due to their close relationship with important neurovascular structures such as the oculomotor and optic nerves, the internal carotid artery and its branches, and the cavernous sinus.10,11,13,15 These neurovascular structures can not only make the procedure more difficult but also limit the extent of resection, which impacts recurrence. When the tumor infiltrates the cavernous sinus, Nakamura et al. reported that only 14.5% of these tumors were able to be completely resected, compared with 92.3% total resection for non-infiltrative tumors.15,16 In addition, tumor infiltration of bony structures such as the optic canal, orbit, and superior orbital fissure, or hyperostosis of adjacent bone is associated with less optimal long-term outcomes and increased tumor recurrence.13,15
Understanding the impact of hyperostosis is crucial for surgical decision-making. Notably, it can significantly influence the operative strategy, potentially necessitating adjustments such as a one-stage tumor removal combined with skull defect reconstruction. By elucidating the relationship between hyperostosis and surgical planning, this clarification not only enhances our comprehension of the pathological effects of these tumors but also aids in preoperative planning and decision-making.18
Clinical features of sphenoid wing meningiomas are also often based on the location of the tumor along the sphenoid wing, and their presentations are usually due to the compression of a nearby structure.1 Visual impairment is the most common preoperative neurologic deficit.13 Meningiomas located on the medial part of the sphenoid wing are often associated with visual disturbances due to their proximity to the optic nerve.2,4 Orbital and cavernous sinus invasion may cause diplopia or exophthalmos. Other sign and symptoms associated with a meningioma may include seizures, headaches, and cognitive impairment.1,3,10
When surgical resection of the meningioma is planned, the preoperative workup focuses heavily on mapping the tumor’s involvement with surrounding neurovascular structures. Pirotte and Brotchi emphasize that a preoperative workup for a sphenoid wing meningioma resection requires MR angiography and venography to depict the tumor’s vascularity, a CT scan with bony windows to check for involvement, and a multiplanar gadolinium-enhanced MRI to assess the tumor boundaries and invasion of the dura.10,15 The middle meningeal arteries play a critical role in supplying blood to sphenoid wing meningiomas. Surgeons should be aware that coagulating the middle meningeal artery early in the surgical procedure is a strategic step. This early coagulation helps quickly devascularize the tumor, which can be crucial for reducing intraoperative bleeding and improving overall visibility and manageability of the surgical field. In cases of large tumors, preoperative embolization of the middle meningeal artery may also be performed.2,10 Surgical exposure and strategy must be tailored to each case individually based on the specific location of the meningioma to avoid both neurologic damage and suboptimal removal.5,10,11,15
Postoperative monitoring is required in the intensive care unit for a minimum of 24 hours following surgery. Steroids are given starting 48 hours before the operation and are continued and tapered postoperatively as needed depending on the level of cerebral edema.10 Postoperative CT is recommended within a few hours of surgery to monitor for postoperative hematoma or pneumocephalus.10,15 Patients should be monitored for a change in mental status or acute onset of neurologic symptoms.
Mortality and morbidity associated with surgical resection of sphenoid wing meningiomas have significantly decreased over the last three decades due to the advances made in the field of neurosurgery, especially in the areas of neuroimaging, cranial base approaches, and microsurgical techniques.15 However, these risks are still significant, especially for medial sphenoid wing meningiomas due to their proximity to the critical neurovascular structures discussed previously.15,17 Complication rates are higher with medial sphenoid wing meningiomas than with those that are lateral and middle.10 Just as the most common preoperative deficits are ocular symptoms, the most common postoperative complications involve the orbital structures. These include visual loss, oculomotor nerve palsy, and diplopia.10,11,13,15 Other new postoperative neurologic deficits may include hemiparesis and aphasia.10,11 While some of these outcomes may be permanent, it is important to consider that many new deficits that appear following surgery may be caused by postoperative edema and are, therefore, likely transient.11 More severe complications requiring further acute management may include hemorrhage, bone infection, cerebrospinal fluid fistula leading to meningitis, and vascular injury.10,15 In order to avoid these complications, extreme care must be taken when dissecting the nearby neurovascular structures, including the oculomotor and optic nerves, and branches of the internal carotid artery. Brain retraction may cause an array of neurologic deficits, and a retractor should never be used on the optic nerve. To avoid the creation of a cerebrospinal fluid fistula, the dural closure and suturing must be watertight.10
Patients are generally monitored for recurrence with MRI for a few years after resection. If a tumor were to recur, it would likely happen within 5 years of surgery.10,15
Nothing to disclose.
The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.
Citations
- Saha R, Jakhar K, Kumar R. Sphenoid wing meningioma presenting as cognitive impairment. Shanghai Arch Psychiatry. 2016;28(3):173-176. doi:10.11919/j.issn.1002-0829.215142.
- Sughrue ME, Rutkowski MJ, Chen CJ, et al. Modern surgical outcomes following surgery for sphenoid wing meningiomas. J Neurosurg. 2013;119(1):86-93. doi:10.3171/2012.12.Jns11539.
- Cohen-Gadol A, Conger AR. Medial sphenoid wing meningioma. The Neurosurgical Atlas 5. doi:10.18791/nsatlas.v5.ch05.3.
- Lund VJ, Rose GE. Endoscopic transnasal orbital decompression for visual failure due to sphenoid wing meningioma. Eye. 2006;20(10):1213-1219. doi:10.1038/sj.eye.6702385.
- Garcia CR, Slone SA, Chau M, Neltner JH, Pittman T, Villano JL. Initial management of meningiomas: Analysis of the national cancer database. Cancer Epidemiol. 2019;60:16-22. doi:10.1016/j.canep.2019.02.018.
- De Jesús O, Toledo MiM. Surgical management of meningioma en plaque of the sphenoid ridge. Surg Neurol. 2001;55(5):265-269. doi:10.1016/S0090-3019(01)00440-2.
- Alexiou GA, Gogou P, Markoula S, Kyritsis AP. Management of meningiomas. Clin Neurol Neurosurg. 2010;112(3):177-182. doi:10.1016/j.clineuro.2009.12.011.
- Ramakrishna NR. Linac-based stereotactic radiosurgery and stereotactic radiotherapy for parasagittal, skull-base, and convexity meningiomas. In: Pamir MN, Black PM, Fahlbusch R, eds. Meningiomas. Philadelphia: W.B. Saunders; 2010:641-649.
- Cernea CR, Teixeira GV, Medina dos Santos LR, Vellutini EA, Siqueira MG. Indications for, contraindications to, and interruption of craniofacial procedures. Ann Otol Rhinol Laryngol. 1997;106(11):927-933. doi:10.1177/000348949710601108.
- Pirotte B.J.M., Brotchi J. (2009) Lateral and Middle Sphenoid Wing Meningiomas. In: Lee J.H. (eds) Meningiomas. Springer, London. doi:10.1007/978-1-84628-784-8_39.
- Champagne PO, Lemoine E, Bojanowski MW. Surgical management of giant sphenoid wing meningiomas encasing major cerebral arteries. Neurosurg Focus. 2018;44(4):E12. doi:10.3171/2018.1.FOCUS17718.
- Simpson D. The recurrence of intracranial meningiomas after surgical treatment. J Neurol Neurosurg Psychiatry. 1957;20(1):22-39. doi:10.1136/jnnp.20.1.22.
- El Badry A, Abdelazeez A. Outcome of medial sphenoidal wing meningioma surgery. Romanian Neurosurg. 2018:40-55.
- Cushing H. Meningiomas: their classification, regional behavior, life history, and surgical end result. Springfield Charles C Thomas. 1938;111:735.
- Güdük M, Özduman K, Pamir MN. Sphenoid wing meningiomas: surgical outcomes in a series of 141 cases and proposal of a scoring system predicting extent of resection. World Neurosurg. 2019;125:e48-e59. doi:10.1016/j.wneu.2018.12.175.
- Nakamura M, Roser F, Jacobs C, Vorkapic P, Samii M. Medial sphenoid wing meningiomas: clinical outcome and recurrence rate. Neurosurg. 2006;58(4):626-639, discussion 626-639. doi:10.1227/01.Neu.0000197104.78684.5d.
- Chaichana KL, Jackson C, Patel A, et al. Predictors of visual outcome following surgical resection of medial sphenoid wing meningiomas. J Neurol Surg B Skull Base. 2012;73(5):321-326. doi:10.1055/s-0032-1321510.
- Maki T, Ito E, Saito K, Saito R. Surgical reconstruction for spheno-orbital meningioma extending into the sphenoid sinus with hyperostosis. Clin Case Rep. 2023;11(7):e7705. Published 2023 Jul 21. doi:10.1002/ccr3.7705.
Cite this article
Miller S, Czabanka M. Resection of a sphenoid wing meningioma. J Med Insight. 2024;2024(143). doi:10.24296/jomi/143.
Procedure Outline
Table of Contents
- Incision
- Retract Skin/Muscle Flap
- Drill Burr Hole
- Use Craniotome and Remove Bone Flap
- Suture Dura to Skull
- Use Rongeur to Widen Exposure
- Drill Sphenoid and Expand Craniotomy Temporally
- Draping and Preparation
- Control Bleeding
- Open Dura
- Locate Tumor
- Devascularize Tumor
- Remove Tumor
- Insert Wire Mesh
- Close Dura
- Refix Bone Flap to Skull
- Close Wound
Transcription
CHAPTER 1
Hello, my name is Marcus Czebanka. Today, we gonna resect a left-sided sphenoid wing meningioma. You can see the images over here. It's a 43-year-old patient that actually complained about short episodes of speech arrest as well as of aura-like symptoms that have been going on for almost 4 weeks. Because of this reason, the patient received an MRI, and the results you can see over there. In order to resect this kind of tumor you need five steps. The first step obviously is the approach and the craniotomy. In order to reach this tumor, we gonna use a pterional approach. The second step would be identification of the tumor and devascularization of the tumor. The third step is preparation of the tumor margins and separation of the tumor margins from the surrounding brain and especially from the internal carotid artery that's very closely associated in this case. The fourth step then is removal of the tumor, and the fifth step will be closing.
CHAPTER 2
So the first step now is skin incision for pterional craniotomy. We always use a combined skin muscle flap for this kind of approach. So we are not gonna separate the muscle over a large area from the skin. Okay, now we place the burr hole. Dissector. So we always place it underneath the temporal muscle. We just use one burr hole. Okay, now we’ve done the cuts for the craniotomy, and we just have a remaining part on the sphenoid bone underneath - and this we gonna drill. Now we gonna flip the flap.\NFlip the flap, that’s a good way of saying it. Now we are gonna flip the flap. Pardon me? It’s bleeding from the meningioma probably.
CHAPTER 3
Now we have finished the craniotomy. We have the extension to the temporal bone, and we also did resect part of the sphenoid wing. So now we are ready to go. And I think after draping we can - we can switch to the microscope. See, I’m annoyed that it’s always oozing from down here. So it’s always - there’s always some bleeding from here. So I have to get rid of this. So now we open the dura after we get hemostasis. So when we incise the dura, we always watch the tip of the scissors - because we make sure we don’t run into the brain. Okay. There we go. There’s the tumor already. Here you can see it. Okay. So what we gonna do now is we’re gonna try to get some CSF. The optic nerve is down here. So we drain CSF now to get some more space. For this purpose, I am opening now the optic cistern. Okay, so down here is the optic nerve. That gives you good control of the medial aspect of the tumor. So now we are going to devascularize the tumor. There you go. So at the moment, I am having trouble getting a clear border between the tumor and the brain. Now I’ve found the - now I’ve finally found the - the clear tumor border. Down here we can see the carotid artery. That’s the large brain-supplying artery. And I think now, we’ve made some progress. Okay. See that was all. I wasn’t able to find a good entry zone into the - for the border of the tumor and the brain. Now since we’ve found it, it's getting much easier. Okay, this we’ll take care of later. See now I’m approaching the circumferential preparation of the tumor borders. So once we have this posterior part, I think we should be all set to just take it out. Here the tumor is still sticking to the dura, so I’m trying to re - go through here, and then we should be able to remove it en bloc. And the most safe part to remove definitely is the temporal polar part of the tumor. So that’s what I chose as the first part that I’m gonna resect. So this is gonna be the second part. So that’s the blood supply of the dura. This - this you should coagulate. So that's - that was basically it. Okay, just to show - okay here again, we have the optic nerve. And right next to it, we have the cari - internal carotid artery. And down here, you can see the oculomotor nerve. But this - everything’s okay. We have some arachnoid on it, so there should be - there should not be any problem with these structures. Just to make sure we don’t have any remnants of the tumor. That would be a pity. Okay, here you can see where the tumor was originating from. This we cannot resect. Therefore, we coagulated. If I ever find the - to get a Simpson grade 2 resection. Okay. So now we start closing the dura. We hope that it will close sufficiently. Sometimes the dura shrinks during surgery. Then we have trouble closing it.
CHAPTER 4
[No Dialogue.]
CHAPTER 5
So this procedure overall went very well. We could resect the tumor without any problems. The surgery was quick, and it was without any complications. In the beginning of the surgery, when I tried to do step number three, which is separation of the tumor margins from the surrounding brain, I had some difficulties because the tumor was very much attached to the surrounding brain, but finally we did get a good plane to really dissect the tumor from the brain. And therefore, the surgery overall went quite quickly without any problems.