Neurosurgery Department, University General Hospital of Alicante, Foundation for the Promotion of Health and Biomedical Research in the Valencian Region (FISABIO), Alicante, Spain
The three subtypes are the superiorly pointing aneurysms originating at the ophthalmic artery (i.e., ophthalmic artery [OA] aneurysms), the medially pointing aneurysms originating from the superior hypophyseal trunk, and aneurysms originating from a perforator-free part of the ICA, the so-called atypical or blister ICA aneurysms 4).
Most commonly, ophthalmic artery aneurysms present with progressive visual disturbance or exophthalmos, although they may be asymptomatic.
Clinical presentations included subarachnoid hemorrhage in 23 cases (29%) and visual deficits in 24 (30%); five patients exhibited both hemorrhage and visual loss. Twenty-eight aneurysms were incidentally identified. Ophthalmic artery aneurysms arose from the internal carotid artery (ICA) just distal to the ophthalmic artery, pointed superiorly or superomedially, and (when large) deflected the carotid artery posteriorly and inferiorly, closing the siphon. Abnormalities relating to vision were not identified until the aneurysm realized giant proportions. The optic nerve was typically displaced superomedially, which restricted contralateral extension until late in the clinical course; unilateral nasal field loss was seen in 12 patients. 5).
Unruptured large OA aneurysms frequently present with gradual loss of vision. The goal of their treatment is then twofold: to exclude the aneurysm from the circulation and to preserve or restore visual function. Treatment of OA aneurysms can be surgical or endovascular, depending on the mode of presentation, aneurysm geometrics and size, as well as the patient́ s medical condition 6).
When direct operation is performed for a carotid-ophthalmic artery aneurysm, care must be taken to avoid optic nerve injury caused by the retraction and/or the heat of the drill 13).
Disadvantages of a contralateral approach (CA) are deep and narrow surgical corridors and inconsistent ability to achieve proximal control of the supraclinoid internal carotid artery (ICA). However, a CA remains as microsurgical option for selected internal carotid artery-ophthalmic segment (ICA-opht) aneurysms.
Its feasibility depends on specific anatomic parameters related to the aneurysm itself and to the prechiasmatic distance, interoptic distance, and relationship of the ICA with the anterior clinoid process 14).
In selected patients, transient cardiac arrest induced by adenosine during a contralateral approach allows a brief flow arrest and softening of the aneurysm for a safer exposure and clipping 15).
Ophthalmic artery aneurysms may be adequately and safely treated with either the Pipeline Embolization Device (PED) or coil embolization. However, treatment with the PED carries a higher risk of impeding flow to the ophthalmic artery, although this did not result in clinical sequelae in a study 16).
A 27-year-old male with no past medical history presented with three months of headaches. Imaging reveled a large dysplastic left A1-2 junction aneurysm and a smaller saccular right A1-2 junction aneurysm, with potentially adherent domes. Two fusiform aneurysms of the intraorbital segment of the left OA were also identified. The patient underwent coil-assisted Pipeline embolization of the left A1-A2 aneurysm, with complete obliteration and reconstitution of the normal parent vessel. The patient underwent coil embolization of the right A1-2 aneurysm 3 weeks later, and was found to have grown significantly at the time of treatment. Three-month follow-up demonstrated spontaneous resolution of the OA aneurysms, persistent obliteration of the left aneurysm and significant recurrence of the right aneurysm, which was treated with stent-assisted coil embolization. A second recurrence three months later was successfully treated with repeat coiling. At the time of this treatment, the patient was also found to have two de novo distal middle cerebral artery (MCA) and ACA dysplastic aneurysms which were not treated. Follow up angiography 6 weeks later demonstrated stable complete obliteration of the right A1-2 aneurysm and interval complete resolution of the dysplastic MCA aneurysm. The distal ACA aneurysm was observed to have minimally increased in size, however, the parent vessel showed signs of interval partial thrombosis with contrast stasis within the aneurysm. This final aneurysm is currently being followed with serial imaging. The patient remains neurologically intact with complete resolution of his headaches.
CONCLUSION: We present a young male with no past medical history who presented with multiple dysplastic aneurysms. Successful staged endovascular intervention resulted in obliteration of aneurysms with spontaneous obliteration of the intraorbital OA aneurysms observed at three months. We present this case to review the multiple challenges of managing complex ACA aneurysms and to highlight the utility of endovascular intervention in their treatment 17).
Peschillo S, Biraschi F, Diana F, Colonnese C, Marenco M, Delfini R. Aneurysms of the Intracranial Segment of the Ophthalmic Artery Trunk: Case Report and Systematic Literature Review. J Neurol Surg A Cent Eur Neurosurg. 2017 Jul 25. doi: 10.1055/s-0037-1604268. [Epub ahead of print] PubMed PMID: 28743134 18).