Transcavernous clipping of ACS aneurysm

A surgery performed by Dr. Carlos Eduardo Da Silva

The treatment of posterior fossa aneurysms remains one of the most complex technical challenges in vascular neurosurgery. In this case, available in the app SurgSchool, the Dr. Carlos Eduardo Da Silva (Universidade Federal de Ciências da Saúde de Porto Alegre – UFCSPA, Brazil) presents the microneurosurgical clipping of an aneurysm of the superior cerebellar artery (SCA) what was grew progressively after previous treatment with flow-diverter.

This procedure masterfully illustrates the value of transcavernous approaches to access the basilar trunk with complete vascular control, even in arteries previously instrumented with endovascular devices.

Clinical history and failure of endovascular treatment

The patient, a 68-year-old woman with long-standing headaches, had been treated at another center using flow-funHowever, during four years of follow-up, the aneurysm increased in size (from 3.1×3 mm to 3.6×3 mm), which is why she was referred to Dr. Da Silva's team.

Both digital angiography and CT angiography showed the relationship of the aneurysm to the device and the persistence of flow in the lesion, confirming the lack of complete exclusion.

Surgical strategy: need for a transcavernous approach

The therapeutic objective was Completely rule out an aneurysm to prevent future rupture. In the context of a basilar artery with a flow diverter, the use of temporary clips can be risky due to the fragility of the arterial wall and the possibility of damaging the stent.

Therefore, Dr. Da Silva opted for a transcavernous approach with extensive bone decompression, allowing:

• Full exhibition of clinoid and ophthalmic segment of the internal carotid artery.
• Safe mobilization of oculomotor nerve through opening of the oculomotor triangle.
• Direct access to basilar trunk proximal to the flow-diverter.
• Simultaneous display of both ACS and from both ACP (segments P1).

This access establishes optimal conditions for meticulous clipping without the need for aggressive temporary occlusion.

Technical details of the approach

The surgery began with the microsurgical dissection of the Sylvian fissure under high magnification. Subsequently:

1. Coagulation and opening of the dura mater on the anterior clinoid process.
2. Intradural milling and en bloc removal of the clinoid process.
3. exhibition of carotid roof, clinoid segment and ophthalmic segment.
4. Opening of the upper dural ring to completely free the internal carotid artery.
5. Opening of the oculomotor triangle and mobilization of the nerve.
6. Opening the Liliequist membrane, exposing the basilar trunk and the proximal end of the flow-diversion device.
7. Identification of the contralateral branches of the basilar trunk through the superior carotid triangle.

This sequence allowed for three-dimensional vascular control of the aneurysm and all its relationships with critical perforators.

Aneurysm clipping and preservation of perforators

The aneurysm, located in the center of the operative field, was completely dissected, exposing both superior coronary arteries (SCAs) and both posterior coronary arteries (PCAs). The right P1 segment showed partial incorporation of the flow-diverter.

The aneurysmal neck was carefully dissected, separating the proximal and distal perforators. Then:

• A was applied first pilot clippreserving the proximal perforator.
• Un second clip He completed the total exclusion of the aneurysm without compromising the perforating branches.
• It was used Gelfoam y fibrin to stabilize the clips and prevent displacements that could pull on the basilar trunk or the oculomotor nerve.

The video ends with postoperative CT angiography images confirming the complete exclusion of the aneurysm.

Relevance to contemporary vascular neurosurgery

This case highlights several key principles:

• Aneurysms that flow-diverter devices fail They may require advanced microsurgical solutions.
• Transcavernous approaches provide wide and safe access to the basilar trunkallowing direct clipping even in complex anatomies.
• Preservation of perforators is a critical objective that requires a generous exposure strategy and refined microsurgical technique.

Access the complete surgery in SurgSchool

The video is available in the app. SurgSchoolwhere neurosurgeons and residents can visualize each step with detailed commentary from Dr. Da Silva.

Direct link to the video:
https://surgschool.com/mobile-app/video/hwpBFog7E3kveSYUjnL2

If you want to learn from the best international specialists and access high-level content in neurosurgery, otolaryngology, interventional radiology and urology, download the app SurgSchool on iOS or Android. More advanced techniques in neuro-oncological and skull base surgery.