崔源生 台中榮民總醫院神經外科

Surgical Treatment of Aneurysms of the Anterior

Wall of the Internal Carotid Artery

Anatomy: ICA:5 segments:

– Cervical

– Petrous

– Cavernous

– Clinoidal

– Supraclinoid

Morphology:

Pathology:

No internal elastic lamina and media

The gap was covered with thin adventitia and fibrinous tissue, not composed of thick adventitia or collagenous tissue as ordinarily seen in an berry aneurysm wall

Pathology:

Pathogenesis:

Atherosclerosis: – (Stehbens,et al:The pathology of

intracranial arterial aneurysms and their complications, Intracranial Aneursyms, 1983, Vol 1)

Dissecting:

Anterior Wall Aneurysm

Dorsal type, Blister-like aneurysm Low incidence Small size Thin wall No neck High intraoperative bleeding rate High morbidity & mortality

Diagnosis: It’s difficult to detect anterior wall

aneurysm on angiograms, in large part because of their small size and unusual location.(Shigeta et al, 6 (30%) negative in 20 pts)

It’s of great importance to evaluate collateral circulation because ICA sacrifice at surgery is relative common with these aneurysms.

Case 1: angiogram (AP+Lat)

Case 1: angiogram (oblique)

Case 2: angiogram

Case 2:

Case 2: CTA

OP Findings:Video

Textbook-Management of Cerebral Aneurysms (2004)

Poor outcome of Anterior Wall ICA Aneurysms:

Aneurysm protruding from the dorsal wall of internal carotid arteryFukuo Nakagawa, et al.J of Neurosurgery 65:303-308, 1986 5 year period, 8 cases/460 ANs

Blood blisterlike aneurysms of the internal carotid arteryMasamitsu Abe, et al.J of Neurosurgery 89:419-424,1998 1981-1997, 6 cases/488 ANs

Abe series: Clipping on wrapping

Aneurysms at nonbranching sites in the supraclinoid portion of the internal carotid artery:Internal carotid artery trunk aneurysmsAkira Ogawa, et al.Neurosurgery 47:578-586, 2000

5 year period, 48 cases/7408 ANs

Ogawa series-outcome:

New method for obliterative treatment of an anterior wall aneurysm in the internal carotid artery: Encircling silicone sheet clip procedure-Technical case report

Yasutaka Kurokawa, et al.Neurosurgery 49:469-472, 2001

Techinical note:

Surgical management: Possible trapping of parent artery

Exposure of cervical ICA for proximal control

Wide open of Sylvian fissure

Little frontal lobe traction

Clip placement parallel to the ICA axis

Necessary to catch the adjacent carotid artery wall with the neck

Temporary clipping to reduce aneurysm turgor

Clipping on wrapping

Endovascular may be an alternative option

Thank you