Aneurysm of the primitive trigeminal artery: a clinical case and a literature review

Background. The primitive trigeminal artery is a fetal anastomosis connecting carotid and vertebrobasilar basins during embryonic period of development. After birth, this artery in the child is obliterated and reduced in most cases. Sometimes the obliteration does not occur and as a result the aneurysms may be formed on this artery (due to change in ordinary hemodynamics in carotid basin), as a consequence, it produces a risk of subarachnoid hemorrhage that sharply worsens prognosis of the disease outcome. The usual microsurgical treatment methods of aneurysms of such localization are of little use and are highly traumatic due to the very “low” location of the neck, because the surgery may need extended basal accesses requiring resection of skull base bones. Also, an “open” surgery produces risks of perforating arteries injury that often extend from trigeminal artery and feed the brain stem, the injury will immediately result in brain ischemic damage. That is why the preferred method for treatment of that kind of pathology may include endovascular intervention both of non‑reconstructive type employing microcoils only and those of reconstructive requiring implantation of assisting or flow‑redirecting stents.Aim. To demonstrate a case of successful treatment of patient with a primitive trigeminal artery aneurysm.Materials and methods. A woman, who was admitted to clinic with complaints of convergent strabismus, undergone surgery for large aneurysm located on primitive trigeminal artery. CT brain angiography revealed large aneurysm of primitive trigeminal artery on the right, the result was later confirmed by data of selective cerebral subtraction angiography. Taking into account oculomotor disorders in the patient, it was decided to refrain from microcoils use due to risk of the mass‑effect preservation. Under double disaggregant therapy (ticagrelor 90 mg twice daily + acetylsalicylic acid 100 mg once daily in the evening) and monitoring the functional activity of platelets, a flow‑deflecting stent was implanted into the right internal carotid artery.Results. The patient was discharged from hospital on the 1st day after the surgery and returned to work. A control angiography performed 3 years later revealed a total shutdown of the aneurysm from bloodstream as well as a partial regression of oculomotor disorders. Intravascular treatment in this situation served as an effective method of choice and made it possible to reliably turn off the aneurysm from bloodstream without impairing the functional outcome of patient’s treatment.Conclusions. It can be assumed that intravascular intervention in case of such aneurysms serves as an effective method of choice as minimally invasive and low‑traumatic surgery in the treatment of patients with that type of pathology.