Horner Syndrome

Horner Syndrome is a condition that affects the nerves controlling certain muscles in the face and eye. It involves the sympathetic nervous system, which helps regulate pupil size, eyelid position, and sweating on one side of the face. People with this syndrome often have a drooping eyelid (ptosis), a small pupil (miosis), and decreased sweating on the affected side. These changes happen because the nerve signals that normally keep these functions active are disrupted. The syndrome can result from injury or disease affecting the nerve pathway from the brain to the face. It mainly impacts the eye and facial muscles, causing noticeable asymmetry. Understanding these symptoms helps identify the underlying cause and guide further evaluation.

Horner Syndrome is a neurological disorder caused by disruption of the oculosympathetic pathway, which is a three-neuron chain responsible for sympathetic innervation to the eye and face. The syndrome results from lesions anywhere along this pathway, including the hypothalamus, brainstem, spinal cord, or sympathetic chain. Common causes include stroke, tumor, trauma, or carotid artery dissection. The classic clinical triad includes ptosis, miosis, and anhidrosis on the ipsilateral side. The syndrome is significant because it localizes lesions affecting the sympathetic nervous system and may indicate serious underlying pathology. Diagnosis requires careful clinical examination and often imaging to identify the lesion site. Recognition of Horner Syndrome is critical for prompt management of potentially life-threatening causes.