Anisocoria indicates a difference in pupil diameter; in common clinical manifestations, if anisocoria is more marked in bright light, the large pupil is abnormal, while if anisocoria is more marked with reduced illumination, the small pupil is abnormal. Besides, a pupillary diameter difference less than 1 mm is often a physiological condition occurring in about 20% of the population.

 Etiologies of this clinical manifestation usually include local and systemic causes. Systemic causes are neurological or vascular disorders, usually associated with raised intracranial pressure or a consequence of traumatic or hypoxemic lesions of the Parasympathetic and Orthosympathetic Nervous System.

Local causes reported in Literature are synechia, congenital iris disorders (coloboma and aniridia) and pharmacological effects. 3 A rather rare occurrence is intravascular embolization of local anesthetics containing vasoconstrictors. In the clinical practice, an intraoperative or postoperative anisocoria is assessed according to its cause. Knowing this clinical event and the rapid identification of the trigger factor is the basis of a correct and timely therapeutic approach, which, in severe cases, could save the patient’s life.


Francesco Inchingolo1,4 , Marco Tatullo2, Fabio M. Abenavoli3, Massimo Marrelli4, Alessio D. Inchingolo1, Bruno Villabruna4, Angelo M. Inchingolo5, Gianna Dipalma4 1. Department of Dental Sciences and Surgery, General Hospital, Bari, Italy 2. Department of Medical Biochemistry, Medical Biology and Physics, General Hospital, Bari, Italy 3. Department of ?Head and Neck diseases?, Hospital ?Fatebenefratelli?, Rome, Italy 4. Department of Maxillofacial Surgery, Calabrodental, Crotone, Italy 5. Department of Surgical, Reconstructive and Diagnostic Sciences, General Hospital, Milano, Italy