Optic Nerve Head Microvascular Changes Associated with Intracranial Aneurysms.

Objectives: The aim of our study is to report optic nerve head (ONH) microvascular changes secondary to intracranial saccular aneurysms, evaluated by optic coherence tomography angiography.

Methods: A prospective study was conducted on consecutive intracranial saccular aneurysm patients who underwent neurosurgical intervention and consulted for ophthalmic evaluation at the post-operative period. Comprehensive ophthalmic evaluation, including best-corrected visual acuity, manifest refraction, color vision, pupillary light reflexes, intraocular pressure, slit-lamp biomicroscopy, fundoscopy, and investigation of the function of cranial nerves, was performed. Demographical and clinical data of eyes with intracranial aneurysm (Group 1) were compared to those of age-matched controls (Group 2). In patients with unilateral intracranial aneurysm, microvascular indices of the ipsilateral eye were also compared with those of the contralateral eye.

Results: Twenty-eight eyes of 16 patients in Group 1 and 32 eyes of 16 age-matched healthy controls in Group 2 were included in the study. In Group 1, only 1 patient was diagnosed incidentally, whereas the remaining 15 patients were diagnosed after subarachnoid hemorrhage (SAH). ONH microvascular indices were similar in both groups (p>0.05). Both vascular density and thickness were decreased at the nasal inferior sector of ONH in Group 1, compared to Group 2; however, these differences were statistically insignificant. In Group 1, 8 patients have unilateral intracranial aneurysm. Microvascular indices at the ipsilateral eye were statistically insignificantly increased compared to those at the contralateral eye of patients with unilateral intracranial aneurysm.

Conclusion: Intracranial saccular aneurysms, associated SAH, or neurosurgical intervention did not seem to cause any significant change in ONH microvascular indices. Further studies with a larger sample size and evaluating intracranial aneurysms located in different anatomical regions will contribute to the interpretation of the present results.