Cuối cùng, các vết mờ mắt trái, đặc biệt là dưới ánh sáng mặt trời, kinh nghiệm của các bệnh nhân trong các họa tiết cho thấy một đặc tính có thể có của động mạch cảnh rối loạn chức năng hoặc mù fugax. Tập thoáng mất thị giác đã được mô tả như là hình ảnh che chướng | 68 7. Cerebrovascular Disorders in Adults dysfunction and less commonly isolated dysphasia. The duration of the transitory attack is brief usually less than 10 minutes. Finally the blurriness of the left eye especially under sunlight experienced by the patient in the vignette indicates another possible characteristic of carotid dysfunction or amaurosis fugax. Transient episodes of visual loss have been characterized as brief monocular visual obscuration blur cloud fog or shade which usually lasts less than 15 minutes Barnett et al. . It has also been reported that exposure to bright light often sunlight precipitates transient unilateral visual loss Barnett in patients with high-grade stenosis. Considering these vascular transitory events the localization resides in the left anterior circulation carotid artery territory. These episodes can be caused by an embolic mechanism with sources originating from the heart or from ath-erothrombotic carotid plaques. Also severe hypoperfusion due to high-grade carotid stenosis is another mechanism. A cardiac source seems unlikely in the patient described because there are no known cardiac factors and the transitory attacks do not involve multiple vascular territories as seen with cardiac embolization. Other important causes to be considered in the differential diagnosis are primary and secondary inflammatory vascular disorders. Primary inflammatory vascular disorders include systemic vasculitis systemic lupus antiphospholipid antibody syndrome and others. Secondary inflammatory vascular disorders occur with infections drugs irradiation and so on. Important factors that lead to the right diagnosis are systemic features such as weight loss anorexia headache malaise low-grade fever arthralgia livedo reticularis and so on. Arterial dissection is another possibility to be kept in mind as cause of TIA or stroke and is usually related to trauma. As stated earlier the differential diagnosis of transient focal neurological symptoms of .
