Neurophysiology Research

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Editorial - Neurophysiology Research (2023) Volume 5, Issue 4

Anisocoria: Understanding the mismatched pupils phenomenon

Manik Quist *

Department of Ophthalmology, Duke University School of Medicine, Durham, USA.

*Corresponding Author:
Manik Quist
Department of Ophthalmology,
Duke University School of Medicine
Durham, USA

Received:14-Jul-2023, Manuscript No. AANR-23-110795;Editor assigned: 17-Jul-2023, PreQC No. AANR-23-110795(PQ);Reviewed:31-Aug-2023, QC No. AANR-23-110795;Revised:02-Aug-2023, Manuscript No. AANR-23-110795 (R); Published:09-Aug-2023, DOI: 10.35841/ aanr-5.4.160

Citation: Manik Quist. Anisocoria: Understanding the mismatched pupils phenomenon. Neurophysiol Res. 2023; 5(4):160

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Our eyes are the windows to the world, providing us with invaluable sensory information about our surroundings. They allow us to perceive the beauty of nature, the complexities of art and the faces of our loved ones. But what happens when these windows begin to show an uneven view, when one pupil appears larger or smaller than the other? This intriguing and sometimes perplexing phenomenon is known as anisocoria. A condition that highlights the complexity and wonder of our visual system.


Anisocoria is a medical term derived from the Greek words "an" (unequal) and "isokoros" (pupil), literally translating to "unequal pupils." It refers to a condition in which an obvious and persistent difference in pupil size exists between the two eyes. Normally, pupils of the same person should be of equal size, responding symmetrically to changes in light and other stimuli. However, anisocoria disrupts this balance, leading to one pupil being either larger or smaller than its counterpart [1].

Causes and mechanisms

Anisocoria can result from a variety of underlying causes, ranging from benign to potentially serious. The pupils' size is controlled by the iris muscles and the autonomic nervous system. When these systems encounter issues, anisocoria can develop. One common cause of anisocoria is physiological anisocoria, a benign condition where slight and equal variations in pupil size are normal and not indicative of any underlying problem. These small disparities are often more noticeable in conditions of dim lighting or when the pupils are examined up close [2].

Pathological anisocoria, on the other hand, points to an underlying medical issue. Neurological conditions like Horner's syndrome, a disruption of the sympathetic nerve pathways, can cause one pupil to constrict and appear smaller. Conversely, an unopposed parasympathetic response might result in a larger pupil on one side, often seen in cases of Adie's tonic pupil. Trauma, inflammation and eye surgery can also lead to anisocoria. Head injuries and brain lesions may affect the nerves controlling pupil size and reactivity. Infections, such as syphilis or herpes zoster, can also damage the nerves and result in unequal pupil sizes [3].

Diagnosis and Management

Diagnosing the cause of anisocoria requires a comprehensive eye examination and often involves assessing the pupils' response to light, accommodation and convergence. Anisocoria might be the first sign of an underlying condition, making early detection crucial. The treatment of anisocoria depends on its underlying cause. Benign physiological anisocoria typically doesn't require treatment, as it's a normal variation. However, pathological anisocoria necessitates addressing the root issue. This might involve managing neurological conditions, infections, or other contributing factors. In some cases, pharmacological interventions or surgical procedures may be necessary to restore balance to the pupils' size and reactivity [4].

Beyond its medical implications, anisocoria is a reminder of the intricate and multifaceted nature of human perception. Our eyes, often taken for granted, engage in a complex dance of physiological processes, neural signalling and sensory interpretation. The condition sparks curiosity about how our brain processes visual information and how minor disruptions can lead to noticeable differences in what we perceive. Anisocoria has even found its way into the world of literature and film, serving as a symbolic representation of characters with enigmatic or complex personalities. The mismatched pupils can be a visual cue that something lies beneath the surface, inviting audiences to delve deeper into a character's psyche and motivations [5].

Treatment and Management

Timely treatment is of paramount importance in managing GCA and preventing complications. Corticosteroids, such as prednisone, are the primary treatment option. They effectively reduce inflammation and help alleviate symptoms. However, long-term corticosteroid use can lead to a range of side effects, including osteoporosis, diabetes, and hypertension. Therefore, finding the lowest effective dose is crucial to minimize these risks [4].

In some cases, immunosuppressive medications may be considered alongside corticosteroids to enable steroid dose reduction. These medications, such as methotrexate or tocilizumab, can help maintain disease control while reducing the reliance on high doses of corticosteroids. Regular monitoring is essential to track disease progression and assess the effectiveness of treatment. In cases of vision-related symptoms, immediate medical attention is vital to prevent irreversible damage [5].


Anisocoria, the phenomenon of unequal pupil size, is a captivating yet medically significant condition. It reminds us of the delicate balance required for our senses to function harmoniously and offers a glimpse into the intricate mechanisms that govern our perception of the world. Whether benign or indicative of an underlying health issue, anisocoria showcases the interconnectedness of our body, mind and the mysteries that lie within. Regular eye check-ups and a deeper understanding of our visual system are essential to unravelling the secrets behind this fascinating occurrence.


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