horner征表现及临床意义（Horner Syndrome A Comprehensive Overview of Clinical Manifestations and Sig

Horner Syndrome: A Comprehensive Overview of Clinical Manifestations and Significance

Introduction:

Horner syndrome (HS) is a rare condition characterized by a triad of symptoms, including ptosis, miosis, and anhidrosis, all resulting from the interruption of the sympathetic innervation of the eye and face. In this article, we discuss the pathophysiology, causes, clinical manifestations, and diagnostic workup of HS.

Pathophysiology and Causes of HS:

HS results from damage to the sympathetic pathway that innervates the head and neck regions. The damage may occur at different levels of the sympathetic nervous system, including the hypothalamus, brainstem, cervical spinal cord, and/or the superior cervical ganglion. HS can be classified into three subtypes based on the site of the underlying lesion: preganglionic, postganglionic, and central. The most common causes of HS include traumatic injury, surgical trauma, neoplasms, idiopathic, and vascular disorders. Certain medications may also cause HS, including cocaine, opioids, and nebulized epinephrine.

Clinical Manifestations of HS:

The classic triad of HS symptoms include ptosis, miosis, and anhidrosis. Ptosis refers to drooping of the eyelid due to the interruption of the sympathetic pathway that controls the levator palpebrae superioris muscle. Miosis is a constriction of the pupil due to the loss of dilator pupillae muscle function. Anhidrosis refers to a decrease or absence of sweating on the affected side of the face. Other less-common symptoms related to HS include facial flushing, headache, neck pain, and heterochromia. Due to various underlying causes of HS, other neurological signs and symptoms may be present, such as gait disturbances, limb weakness, and sensory deficits.

Diagnostic Workup of HS:

The evaluation of HS should include a thorough physical examination and a detailed medical history to identify any potential underlying etiology. Imaging studies, such as CT scan or MRI, may also be necessary to identify the site of the sympathetic nerve damage or lesion. Pharmacological testing, such as the application of topical cocaine or hydroxyamphetamine, can help distinguish the site of sympathetic nerve damage by determining if the lesion is preganglionic or postganglionic. In conclusion, HS is a rare condition that results from the interruption of the sympathetic nervous system to the head and neck area with a classic triad of symptoms, including ptosis, miosis, and anhidrosis. The underlying etiology of HS may be associated with varying degrees of neurological symptoms and should be investigated with a thorough diagnostic workup.