CASE REPORTS
A 42-years-old male with body mass index of 25kg/m2, presented with two episodes of right retro-orbital pain with loss of vision in the right eye. No history of headache, nystagmus or strabismus. No loss of consciousness. He had no history of head injury. No history of diabetes or increased triglycerides . He was a newly diagnosed well-controlled essential hypertensive on 5mg amlodipine. His admission blood pressure was 135/80mmHg. He was on Plavix 75mg and Aspirin 75mg daily due to the previous intracranial flow diverter. No family history of aneurysm. Physical examination showed normal extraocular muscles and no cranial nerve palsy. Pupils were equal and reactive to light and accommodation. No other neurological deficit was elicited.
His admission magnetic resonance cerebral angiography demonstrated a huge right cavernous saccular aneurysm (Fig 1). 24hours later, 42.5 x 35mm Pipeline Flex embolization device (PED) (Intracranial flow diverter stent) was deployed across the cavernous internal carotid artery aneurysmal neck to exclude the aneurysm from the parent artery. No immediate complication was noted. No contrast medium reaction was reported for 6months. Patient was discharged after 24hours on prasugrel. Patient reported improvement in the symptoms with no new symptoms. Follow up skull radiographs at one and six months showed PED stent migration.
A follow-up right internal carotid artery and vertebral artery digital subtraction angiography at 6months was done using a right radial artery approach with a 5F DAV catheter. 0.5ml/kg of Omnipaque 300 mg/ml contrast medium diluted to 50% with normal saline was used for the angiography. The internal carotid angiogram showed proximally migrated stent into the sac of the aneurysm (fig 2) with no extravasation of contrast medium. During the same procedure, when the right vertebral artery was canulated and contrast medium injected, the patient became suddenly aggressive, he experienced brief tonic seizure (lasting about 30seconds), followed by horizontal nystagmus, tinnitus, loss of vision and incoherent speech. Over a period of one hour after the seizure seized, he became calm, coherent in speech and gradually recovered his vision in that order. The procedure was aborted. His blood pressure during and after the procedure were stable between 140/80 – 145/84mmHg. His renal function and electrolytes were within normal limits.
Review of the angiograms did not show any vascular occlusion or spasm in the vertebrobasilar and internal carotid artery territories. Brain Magnetic Resonance Imaging was arranged within two hours after angiography and demonstrated nonspecific patchy T1- weighted hypo-intensities and T2-weighted hyper-intensities in the periventricular areas. No restricted diffusion was seen on diffusion weighted images and apparent diffusion coefficient (Fig. 3). Gadolinium was not used since the non-contrast images were non-specific. Computed Tomography scan of the brain was not done because, the authors were of the opinion that T2 weighted MRI images were more sensitive to fluid related abnormalities and to reduce the radiation to the patient. Patient was discharged after 24hours of observation. Three months follow after discharged was unremarkable.