The Subtemporal Interdural Approach to Dumbbell-Shaped Trigeminal Schwannomas: Cadaveric Prosection

2006 ◽  
Vol 59 (suppl_4) ◽  
pp. ONS-270-ONS-278 ◽  
Author(s):  
Samy Youssef ◽  
Eun-Young Kim ◽  
Khaled M.A. Aziz ◽  
Salah Hemida ◽  
Jeffrey T. Keller ◽  
...  

Abstract OBJECTIVE: Successful resection of dumbbell-shaped trigeminal schwannomas via a subtemporal interdural approach requires an understanding of both the anatomy related to the bone dissection of the petrous apex (Kawase's triangle or quadrilateral) and meningeal anatomy. We studied the meningeal anatomy related to this approach and describe the dural incisions and stepwise mobilization. METHODS: Meningeal anatomy around Meckel's cave and porus trigeminus was examined during the subtemporal interdural anterior transpetrosal approach in both sides of 15 cadaveric heads. Histological study of the Meckel's cave region was performed in two cadaveric heads. RESULTS: The Gasserian ganglion and trigeminal roots have two layers of dura propria on their dorsolateral surface: an inner layer from the posterior fossa dura propria that constitutes the dorsolateral wall of Meckel's cave and an outer layer from the dura propria of the middle fossa. The cleavage plane between these two layers continues distally as the cleavage plane between the epineural sheaths of the trigeminal divisions and the dura propria of the middle fossa. This cleavage plane serves as the anatomic landmark for the interdural exposure of the contents of Meckel's cave. The superior petrosal sinus is sectioned at the medial aspect of Kawase's triangle and reflected along with the porus trigeminus roof. CONCLUSION: Understanding the critical meningeal architecture in and around Meckel's cave allows experienced cranial neurosurgeons to develop a subtemporal interdural approach to dumbbell-shaped trigeminal schwannomas that effectively converts a multiple-compartment tumor into a single-compartment tumor. Dural incisions and stepwise mobilization complements our previous description of the bony dissection for this approach.

2017 ◽  
Vol 13 (2) ◽  
pp. 163-172
Author(s):  
Shunsuke Shibao ◽  
Hamid Borghei-Razavi ◽  
Kazunari Yoshida

Abstract BACKGROUND: Although the greater superficial petrosal nerve (GSPN) is an important landmark of the anterior transpetrosal approach (ATPA), bleeding from the interdural space around the foramen spinosum (FS), the GSPN, and the foramen ovale impedes the identification of the GSPN, during epidural dissection in the ATPA. OBJECTIVE: To describe the technique of intraspinosum middle meningeal artery (MMA) ligation, which enables us to control bleeding from the interdural space. METHODS: During epidural dissection, we identified the FS and partially drilled the lateral side of the FS. Next, we cut the convergence site of the neurovascular structures such as the MMA, middle meningeal vein, and the meningeal branch of the mandibular nerve with the periosteal dura within the FS and continued dural detachment epidurally to expose the petrous apex. Bleeding control around the FS and postoperative facial nerve paresis were assessed for 96 patients treated with the ATPA. Additionally, histological study was performed around the FS using Masson's trichrome stain. RESULTS: In all cases, in which this technique was used, bleeding from the interdural space was well controlled and no persistent facial nerve paresis was identified. In the histological study, we confirmed that the MMA, the middle meningeal vein, and the meningeal branch of the mandibular nerve converged into the FS and many venous channels existed in the interdural space around the FS and the foramen ovale. CONCLUSION: Intra-FS MMA ligation is an effective method for control of bleeding from the interdural space of the middle fossa during the ATPA.


1988 ◽  
Vol 68 (4) ◽  
pp. 645-647 ◽  
Author(s):  
Michael G. Fehlings ◽  
William S. Tucker

✓ A case of a cavernous hemangioma located within Meckel's cave and involving the gasserian ganglion is described in a patient presenting with facial pain and a trigeminal nerve deficit. Although these lesions have been reported to occur in the middle fossa, this is believed to be the first case of such a vascular malformation arising solely from within Meckel's cave.


2019 ◽  
Vol 80 (S 03) ◽  
pp. S300-S301
Author(s):  
Stephan A. Munich ◽  
Jacques J. Morcos

The retrosigmoid intradural suprameatal approach was first introduced in 1983 by Samii et al, as a modification of the classic retrosigmoid approach intended to open Meckel's cave, exposing the trigeminal nerve and access the middle fossa.1 The area of bone resected in this approach is similar to that removed in a Kawase's approach.2 Whereas the direction of drilling in a Kawase's approach is from anterior and superior, it is from posterior and inferior in the retrosigmoid intradural suprameatal approach. Seoane and Rhoton quantified the exposure of Meckel's cave, finding that this approach allowed access, on average, to the posterior 10.3 mm of Meckel's cave.3 This was confirmed by Chanda and Nanda who found that suprameatal drilling resulted in a mean gain of exposure of the trigeminal nerve of 10.7 mm.4 In this video, we present the case of a patient when an enlarging petrous apex meningioma with extension into Meckel's cave (Fig. 1). The patient underwent a retrosigmoid intradural suprameatal approach to achieve a Simpson's grade II resection. This approach was ideally suited for this case to obtain access to tumor located at the petrous apex and within Meckel's cave (Fig. 2). Without access to Meckel's cave provided in this approach a significant portion of tumor would have remained in situ.The link to the video can be found at: https://youtu.be/eNldkF4a_OI.


2021 ◽  
Author(s):  
Yuanzhi Xu ◽  
Benjamin K Hendricks ◽  
Maximiliano Alberto Nunez ◽  
Ahmed Mohyeldin ◽  
Juan C Fernandez-Miranda ◽  
...  

Abstract BACKGROUND Understanding the microsurgical anatomical features of the endoscopy-assisted retrosigmoid intradural suprameatal approach (RISA) is critical for surgeons treating petroclival tumors or lesions in the cerebellopontine region that extend into Meckel's cave. OBJECTIVE To evaluate increased exposure for Meckel's cave in the RISA and assess the surgical landmarks for this approach. METHODS A standard retrosigmoid craniotomy to the cerebellopontine region was performed in 4 cadaveric specimens (8 hemispheres) with microscope-assisted endoscopy. The length and depth of the drilling region from the suprameatal tubercle to the petrous apex were analyzed. After opening Meckel's cave and mobilizing the trigeminal root completely, the landmarks for this approach were investigated. RESULTS The endoscopy-assisted RISA facilitates mobilization of the trigeminal root and enhances surgical exposure in the region of Meckel's cave and the petrous apex with increases of 10.1 ± 1.3 mm in depth, 21.4 ± 3.2 mm in length, and 6.4 ± 0.6 mm in height. The posterior and superior semicircular canals, internal auditory canal, superior petrous sinus, and internal carotid artery (petrous segment) served as important landmarks for this approach. One case illustration is presented to describe the application of this approach. CONCLUSION The RISA is suitable mainly for lesions in the posterior fossa that extend into Meckel's cave. The endoscopy-assisted reach optimizes accessibility to the petrous apex region, obviates the need for extensive drilling, and decreases the risk of internal carotid artery injury. Better realization and recognition of microsurgical landmarks and parameters of this approach are crucial for successful outcomes.


2018 ◽  
Vol 16 (6) ◽  
pp. E172-E173
Author(s):  
Ken Matsushima ◽  
Michihiro Kohno ◽  
Nobuyuki Nakajima ◽  
Norio Ichimasu

Abstract The combined transpetrosal approach enables wide exposure around the petroclival region by cutting the tentorium and superior petrosal sinus. We often choose this approach for removal of tumors ventral to the facial and vestibulocochlear nerves, such as petroclival meningioma and epidermoid cyst, because complete removal of the tumor under direct visualization is required to prevent its later recurrence, especially in young patients. Recent reports revealed anatomical variations of the drainage of the superior petrosal sinus, and dural incision considering preservation of the superior petrosal vein was proposed.1-3 This 3-dimensional video shows a patient with an epidermoid cyst, which was surgically treated using the combined transpetrosal approach, with consideration of the variation of the superior petrosal sinus and preservation of the drainage route of the superior petrosal vein. The video was reproduced after informed consent of the patient. The patient is a 31-yr-old woman who presented with a left cerebellopontine angle epidermoid cyst extending into Meckel's cave. The superior petrosal sinus was of the lateral type, draining only laterally into the transverse–sigmoid junction without medial connection with the cavernous sinus.1 The combined transpetrosal approach was performed with cutting of the superior petrosal sinus medial to the entry point of the superior petrosal vein, in order to preserve its drainage into the transverse–sigmoid junction. Meckel’ cave was opened along its lateral margin, and tumor removal was accomplished, leaving only a minute part of the capsule strongly adhering to the neurovascular structures. The patient had no new permanent neurological deficits during follow-up. The figures in the video were modified from Matsushima et al1 by permission of the Congress of Neurological Surgeons.


2000 ◽  
Vol 92 (2) ◽  
pp. 235-241 ◽  
Author(s):  
Madjid Samii ◽  
Marcos Tatagiba ◽  
Gustavo A. Carvalho

Object. The goal of this study was to determine whether some petroclival tumors can be safely and efficiently treated using a modified retrosigmoid petrosal approach that is called the retrosigmoid intradural suprameatal approach (RISA).Methods. The RISA was introduced in 1983, and since that time 12 patients harboring petroclival meningiomas have been treated using this technique. The RISA includes a retrosigmoid craniotomy and drilling of the suprameatus petrous bone, which is located above and anterior to the internal auditory meatus, thus providing access to Meckel's cave and the middle fossa.Radical tumor resection (Simpson Grade I or II) was achieved in nine (75%) of the 12 patients. Two patients underwent subtotal resection (Simpson Grade III), and one patient underwent complete resection of tumor at the posterior fossa with subtotal resection at the middle fossa. There were no deaths or severe complications in this series; all patients did well postoperatively, being independent at the time of their last follow-up examinations (mean 5.6 years). Neurological deficits included facial paresis in one patient and worsening of hearing in two patients.Conclusions. Theapproach described here is a useful modification of the retrosigmoid approach, which allows resection of large petroclival tumors without the need for supratentorial craniotomies. Although technically meticulous, this approach is not time-consuming; it is safe and can produce good results. This is the first report on the use of this approach for petroclival meningiomas.


2021 ◽  
Author(s):  
Kunal V Vakharia ◽  
Ryan M Naylor ◽  
Ashley M Nassiri ◽  
Colin L W Driscoll ◽  
Michael J Link

Abstract Epidermoid cysts are rare, benign lesions that result from inclusion of ectodermal elements during neural tube closure.1 Cysts are composed of desquamated epithelial cells and restrict diffusion on magnetic resonance imaging (MRI).2,3 Symptoms are attributable to anatomic location.4,5 In this video, we illustrate the surgical treatment of an epidermoid cyst located in the right cerebellopontine angle, petrous apex, and Meckel's cave. The patient, a 33-yr-old female with right-sided V1 trigeminal hypoesthesia, underwent surveillance imaging for 2 yr. However, she developed progressive V1 and V2 trigeminal hypoesthesia and imaging revealed enlargement of the lesion. Therefore, surgical resection was pursued. The patient consented to the procedure. The patient underwent a right middle fossa craniotomy and anterior petrosectomy. After identifying the greater superficial petrosal nerve and cutting the middle meningeal artery as it exited foramen spinosum, Kawase's triangle was drilled, and the dura over Meckel's cave and the subtemporal dura were opened. The lesion was resected, taking care to preserve the trigeminal nerve and the basilar artery. A retrosigmoid craniotomy was then fashioned. The cyst and its capsule were dissected off the brainstem and cranial nerves utilizing natural corridors between the trigeminal and vestibulocochlear nerves as well as between the facial and lower cranial nerves. Gross total resection was confirmed on postoperative MRI, and she was discharged home on postoperative day 5. Three months after surgery, she underwent formal pinprick testing, which revealed 95% loss of sensation in V1, 20% loss in V2, and normal sensation in V3. Three-month postoperative MRI showed no residual tumor.


2017 ◽  
Vol 13 (5) ◽  
pp. 614-621 ◽  
Author(s):  
Blake Harrison Priddy ◽  
Cristian Ferrareze Nunes ◽  
Andre Beer-Furlan ◽  
Ricardo Carrau ◽  
Iacopo Dallan ◽  
...  

Abstract BACKGROUND: In the last decade, endoscopic skull base surgery has significantly developed and generated a plethora of techniques and approaches for access to the cranial ventral floor. However, the exploration for the least-aggressive, maximally efficient approach continues. OBJECTIVE: To describe in detail an anatomical study, along with the technical nuances of a novel endoscopic approach to Meckel's Cave (MC) using a lateral transorbital (LTO) route. METHODS: Eighteen orbits of injected cadaveric specimens were operated on, using an endoscopic LTO approach to MC, middle cranial fossa, and paramedian skull base preserving the orbital rim. Surgical navigation and an after-the-fact infratemporal craniectomy were utilized to identify the limits of the approach. RESULTS: Following a transorbital approach opening a trapezoid window at the superolateral aspect (average 166.7 mm2), a middle fossa “peeling” and full visualization of MC was accomplished with no difficulties in all specimens. The entire approach was performed extradurally without the need to expose the temporal lobe. CONCLUSION: In a cadaveric model, the endoscopic LTO approach affords a direct route to access MC. Its main advantage is that it is minimally disruptive in nature, less brain retraction is required, and it reaches the middle fossa in an anterolateral perspective. It also requires no manipulation of the temporalis muscle, limited cosmetic incision, and rapid recovery. It seems a viable alternative to traditional approaches for lesions lateral to the cranial nerves at the cavernous sinus and MC, that is, schwannomas. Clinical utilization of this approach will challenge its efficacy and identify limitations.


2020 ◽  
Author(s):  
Ali Tayebi Meybodi ◽  
James K Liu

Abstract Resection of large trigeminal schwannomas involving both posterior and middle cranial fossae is challenging. The depth of the surgical target in the superomedial corner of the cerebellopontine angle and the petrous apex makes for a difficult lesion to favorably access, expose, and safely resect. Judicious planning of a skull base approach is therefore the most crucial step in successful management of these formidable tumors. When properly chosen, planned, and executed, the combined petrosal approach sets the stage for an optimal exposure of such tumors that involve both posterior and middle cranial fossae. The present video is the first of a 2-part video presentation that explains the anatomic rationale of selecting a combined petrosal approach (anterior petrosectomy and retrolabyrinthine petrosectomy) for the resection of a large trigeminal schwannoma involving the posterior and middle cranial fossae with an extension into Meckel's cave in a 54-yr-old female presenting with 5-yr history of increasing headaches, left-sided face numbness, and disequilibrium. The benefits, risks, and alternatives of the surgical procedure were discussed in detail with the patient and she consented to proceed with surgery. Part I also discusses the important nuances of positioning the patient, as well as planning and execution of the skin incision, including pericranial flap harvesting.  Of note, the patient consented to the publication of images obtained from her.


Sign in / Sign up

Export Citation Format

Share Document