Stent-assisted coiling of intracranial carotid ophthalmic segment aneurysm segment aneurysms: Long-term follow-up from a single center

Background

To evaluate the efficacy of stent-assisted coiling (SAC) for the treatment of carotid ophthalmic segment aneurysm segment aneurysms (OSAs) of the internal carotid artery (ICA) through detailed long-term follow-up of a large patient cohort.

Methods

We retrospectively analyzed 88 consecutive patients with OSAs between January 2009 and January 2020 ​at our center. Angiographic results were evaluated using the modified Raymond grading system and clinical outcomes were evaluated using the mRS scale. The primary endpoints were major aneurysm recurrence and poor clinical outcomes for at least 18 months of follow-up. The patients were asked to attend clinical follow-up assessments and possibly undergo DSA or MR via telephone.

Results

We enrolled 88 patients with 99 OSAs treated with coiling, of whom 76 were treated with SAC. The coiling procedures were successful in all 88 patients. Overall, complications occurred in 8 patients (9.1%). No procedure-related mortality was observed. 67 (76.1%) experienced immediate aneurysm occlusion at the end of the procedure. Long-term angiographic follow-up (18 months) was available in 45/88 aneurysms (51%) (average 18.7 ​± ​5.2 months). Four patients continued their follow-up for 5 years after initial aneurysm treatment. After a clinical follow-up time of 28.7 months (range, 12-51 months), 85 patients (95.5%) achieved favorable clinical outcomes (mRS scores of 0-2).

Conclusions

This study indicates that SAC treatment is a safe and effective therapeutic alternative for ruptured and unruptured OSAs. The procedural risks are low with relatively long-term effectiveness.

How I do it: extradural clinoidectomy

BACKGROUND

Removal of the anterior clinoid process expands the anterolateral corridor. Performed extradurally, the dura provides intracranial contents some protection.

METHODS

The anatomy of the anterior clinoid process is described along with variants of the surrounding structures. In addition to an operative video, the anatomy and surgical technique is demonstrated in virtual reality space to enhance the didactic clarity.

CONCLUSION

The anatomical nuances of the lesser sphenoid wing in general, and the anterior clinoid process in particular, are complex. A demonstration in virtual reality takes advantage of the technological flexibility of multi-angled perspectives and focuses on the relevant key structures.

Extradural anterior clinoidectomy and aneurysm clipping using transcranial neuroendoscopic approach: A case report

RATIONALE

Anterior clinoidectomy is an important technique for neurovascular and skull base surgery. Until now, extradural anterior clinoidectomies have been performed under a microscope in almost all clinical cases, with only one clinical case performed an extradural pathological anterior clinoid process resection using neuroendoscopy. Additionally, no normal ACP resections have been performed extradurally via neuroendoscopy, especially for aneurysms. We tried to perform extradural anterior clinoidectomies by neuroendoscopy.

PATIENT CONCERNS

A 63-year-old woman was admitted to hospital presented with sudden onset of headache without any accompanying neurological deficit. A computed tomography (CT) scan of the head revealed a subarachnoid hemorrhage, which was positioned mainly in the left slyvian fissure and interpeduncular and basilar cisterns.

DIAGNOSES

1. Left side posterior communicating artery aneurysm; 2. subarachnoid hemorrhage.

INTERVENTIONS

Extradural anterior clinoidectomy and aneurysm clipping were performed using transcranial neuroendoscopic approaches.

OUTCOMES

The patient recovered well after the procedure, and the post-operative image view revealed that the ACP had been removed and that the clip was located just at the ACP area.

LESSONS

This case provided the first evidence that extradural anterior clinoidectomy could be performed by transcranial neuroendoscopic approach.

Anterior clinoidectomy using an extradural and intradural 2-step hybrid technique

In Brief: The authors found a practical intraoperative landmark to localize the optic strut during anterior clinoidectomy and used it as the basis for performing anterior clinoidectomy in two steps: extradural phase and intradural phase. This anatomically based technique can increase the safety of anterior clinoidectomy by providing easily identifiable landmarks and reducing intradural bone drilling, which could put the adjacent neurovauscular structures at risk.

Extradural anterior clinoidectomy in the management of parasellar meningiomas: Analysis of 13 years of experience and literature review

BACKGROUND AND AIM

The extradural anterior clinoidectomy (EAC) is a key microsurgical technique that facilitates the resection of tumors located in the parasellar region. There is currently no consensus regarding the execution of the procedure via extradural or intradural nor scientific evidence that supports its routine use. The purpose of this article is to expose our experience in performing EAC as part of the management of the parasellar meningiomas.

MATERIALS AND METHODS

A retrospective analysis of the EAC for parasellar meningioma resection performed in our center between 2003 and 2015 was done. A total of 53 patients were recorded. We analized our series focusing on visual outcomes, resection rates and complications. Through an extensive bibliographic research, we discussed the advantages and disadvantages of the EAC, technical considerations, comparison with the intradural clinoidectomy and its visual impact.

RESULTS

The most frequent tumors were anterior clinoidal meningiomas (33.9%). The most common initial symptoms were decreased visual acuity (45.3%) and headache (22.6%). A gross total resection was achieved in 67.9%, being subtotal in the remaining 32.1%. Regarding the visual deficits 67.9% of the patients presented clinical stability, 22.6% improvement and 9.4% worsening. The degree of tumor resection did not significantly influence post-surgical visual outcomes, either visual acuity (P=.71) or campimetric alterations (P=.53). 24.5% of the patients experienced iiinerve transient paresis and 1.9% permanent. The postoperative cerebrospinal fluid leak rate was 3.8%. Mortality rate was 0%. The mean follow-up was 82.3 months.

CONCLUSIONS

In our experience, EAC is a safe technique that facilitates the resection of the meningiomas located in the parasellar area, helps to achieve early tumor devascularization, reduces the need for retraction of the cerebral parenchyma and could play a positive role in the preservation of visual function and the appearance of tumor recurrences in the anterior clinoid process (ACP).

Quantitative analysis of variable extent of anterior clinoidectomy with intradural and extradural approaches: 3-dimensional analysis and cadaver dissection

BACKGROUND

Drilling of the anterior clinoid process (ACP) is an integral component of surgical approaches for central and paracentral skull base lesions. The technique to drill ACP has evolved from pure intradural to extradural and combined techniques.

OBJECTIVE

To describe the computerized morphometric evaluation of exposure of optic nerve and internal carotid artery with proposed tailored intradural (IDAC) and complete extradural (EDAC) anterior clinoidectomy.

METHODS

We describe a morphometric subdivision of ACP into 4 quadrangles and 1 triangle on the basis of fixed bony landmarks. Computerized volumetric analysis with 3-dimensional laser scanning of dry-drilled bones for respective tailored IDAC and EDAC was performed. Both approaches were compared for the area and length of the optic nerve and internal carotid artery. Five cadaver heads were dissected on alternate sides with intradural and extradural techniques to evaluate exposure, surgical freedom, and angulation of approach.

RESULTS

Complete anterior clinoidectomy provides a 2.5-times larger area and 2.7-times larger volume of ACP. Complete clinoidectomy deroofed the optic nerve to an equal extent as by proposed the partial tailored clinoidectomy approach. Tailored IDAC exposes only the distal dural ring, whereas complete EDAC exposes both the proximal and distal dural rings with complete exposure of the carotid cave.

CONCLUSION

Quantitative comparative evaluation provides details of exposure and surgical ease with both techniques. We promote hybrid/EDAC technique for vascular pathologies because of better anatomic orientation. Extradural clinoidectomy is the preferred technique for midline cranial neoplasia. An awareness of different variations of clinoidectomy can prevent dependency on any particular approach and facilitate flexibility.

How I do it : anterior clinoidectomy and optic canal unroofing for microneurosurgical management of ophthalmic segment aneurysms

BACKGROUND

Power drilling commonly used for anterior clinoidectomy and optic canal unroofing can result in thermal injury to the optic nerve.

METHODS

The authors describe an intradural "limited drill" technique of anterior clinoidectomy and optic canal unroofing for microneurosurgical management of ophthalmic segment aneurysms, where optic canal unroofing is done with 1 mm Kerrison punch and the use of the power drill is restricted to anterior clinoidectomy to avoid thermal injury to the optic nerve. The optic nerve, internal carotid artery (ICA), and aneurysm are covered with wet gelfoam pieces to prevent any inadvertent contact with the drill.

CONCLUSION

"Limited drill technique" is a safe and effective technique of anterior clinoidectomy and optic canal unroofing.

KEY POINTS

• Anterior clinoidectomy and optic canal unroofing is an important skull base technique required for safe clipping of the majority of ophthalmic segment aneurysms • Power drilling commonly used for optic canal unroofing can cause thermal injury to optic nerve • More than 2 mm free space is available around the optic nerve in the optic canal • Foot plate of 1 mm Kerrison punch can be safely introduced within a normal optic canal without causing mechanical injury to the optic nerve • Reflection of posteriorly based dural flap acts as a dural barrier, preventing direct contact of drill bit to optic nerve, internal carotid artery and aneurysm during drilling • Entanglement of cottonoids to rotating drill bit is a major problem in intradural anterior clinoidectomy • Wet gelfoam pieces do not get entangled to the rotating drill bit • Structures surrounding the area of drilling can be covered with wet gel foam pieces to prevent direct contact of the drill to neurovascular structures • Opened cisterns can be covered with wet gelfoam pieces during drilling to prevent deposition of bone dust in the subarachnoid space • "Limited drill technique" of anterior clinoidectomy and optic canal unroofing is a safe and effective technique for the exposure of ophthalmic segment aneurysms.

Microsurgical anatomy of the carotid cave

BACKGROUND

The carotid cave was first described more than 20 years ago, but its relationships to the dural rings defining the clinoid segment of the internal carotid artery (ICA), the carotid collar, and the adjacent osseous structures need further definition.

OBJECTIVE

To further define the microanatomy of the carotid cave and its relationships to the adjacent structures.

METHODS

: The cave and its relationships were examined in cadaveric specimens using 3 to 40× magnification.

RESULTS

The cave is an intradural pouch, found in 19 of 20 paraclinoid areas, that extends below the level of the distal dural ring between the wall of the ICA and the dural collar surrounding the ICA. The distal dural ring is tightly adherent to the anterior and lateral walls of the ICA adjacent the anterior clinoid process and optic strut but not on the medial and posterior sides of the artery facing the upper part of the carotid sulcus where the carotid cave is located. The superior hypophyseal artery frequently arises in the cave. The depth and circumferential length of the cave averaged 2.4 mm (range, 1.5-5 mm) and 9.9 mm (range, 4.5-12 mm), respectively. Aneurysms arising at the level of the cave, although appearing on radiological studies to extend below the level of the upper edge of the anterior clinoid, may extend into and may be a source of subarachnoid space.

CONCLUSION

The surgical treatment of aneurysms arising in the cave requires an accurate understanding of the relationships of the cave to the ICA, dural rings, and carotid collar.