Sir, The persistent trigeminal artery (PPTA) is one of the most frequent carotid vertebral anastomosis and has been associated with aneurysms and vascular malformations.[1,2,3] The PPTA has also been associated with clinical neurological syndromes; however, to date, its association with opercular syndromes (facio-labio-pharyngo-glosso-laryngo-brachial paralysis) has not been described. A 51-year old female patient was brought to the emergency department with complaints of headache and slurred incomprehensible speech. The patient had a history of diabetes (type II), hypertension, and hypothyroidism. In 2004, she had presented with right corona radiata lacunar infarction, and in 2008, with a left basal ganglia hemorrhage, managed with external ventricular drainage. On physical examination, the patient had an inability to protrude the tongue. She did not have any hearing alteration. No anatomical abnormalities were observed on her tongue. No fasciculations were seen. The rest of her physical examination was normal. Computed tomography (CT) scan of the brain was performed that did not show an acute pathology. It was decided to perform cerebral angiography, which showed an aneurysm of the left PPTA [Figure 1]. It was decided to embolize the aneurysm with coils, achieving occlusion of the whole aneurysmal sac [Figure 2]. The patient recovered well after the procedure. A control CT scan was performed that showed no evidence of bleeding. The patient was sent home within 72 hours and continued ambulatory rehabilitation.Figure 1: The preoperative angiography of the left internal carotid artery, lateral and oblique view showing the persistent trigeminal artery aneurysmFigure 2: Postoperative angiography of the left internal carotid artery, showing total occlusion of the aneurysm preserving the persistent trigeminal arteryThe opercular syndrome or Foix–Chavany–Marie syndrome was first reported in 1926 but first described by Magnus in 1837.[4,5] Pathophysiologically, it consists of a bilateral corticobulbar compromise with a voluntary facio-lip-pharyngo-glosso-laryngo-brachial paralysis of the musculature but with preservation of the autonomic and automatic reflexes of the same muscles produced by lesions at the cortical or subcortical level that compromise the anterior opercular area surrounding the insula, closely related to the frontal gyrus and the temporal and parietal lobes. The reported causes of this pathology include perinatal lesions, cerebrovascular disease, trauma, surgery, tumor, encephalitis, toxoplasmosis, and developmental malformations; however, to date, opercular syndrome has not been reported in patients with cerebral aneurysms. The PPTA is a rare embryonic circulatory remnant that can be associated with aneurysms. Saltzman classified the angiographic appearance of PPTA into three types, types 1, 2, and 3.[6,7] The PPTA is a result of regression failure during the basilar artery formation and the development of the posterior communicating artery. Four basal carotid fetal anastomoses are formed on day 24 of fetal embryogenesis (trigeminal, otic, hypoglossal, and intersegmental proatlantal artery). After birth and even during adulthood, this basilar-carotid anastomosis may persist with the PPTA being the most common and accounting for 85% of all persistent primitive anastomoses.[8] Our case showed an opercular syndrome associated with trigeminal artery aneurysm, which satisfactorily resolved with endovascular treatment. The identification of this remnant embryonic structure and its variants should always be considered as an unusual cause of opercular syndrome. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that name and initial will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.