Horner syndrome with transient visual impairment.

Area of Science:

• Neurology
• Ophthalmology
• Vascular Surgery

Background:

• Horner syndrome (HS) is characterized by ptosis, miosis, and anhidrosis, often indicative of neurological compromise.
• Internal carotid artery dissection (ICAD) is a critical condition that can lead to ischemic stroke and other neurological deficits.
• Spontaneous ICAD, particularly with minimal risk factors, necessitates thorough investigation due to its potential severity.

Observation:

• A 57-year-old female presented with symptoms consistent with Horner syndrome, including headache, miosis, and ptosis.
• The patient experienced delayed diagnostic imaging and subsequently developed transient, unilateral visual impairment, particularly in bright light.
• Despite minimal cardiovascular risk factors and no history of trauma, the underlying cause was identified as spontaneous internal carotid artery dissection.

Findings:

• The internal carotid artery dissection led to secondary retinal ischemia, explaining the visual disturbances.
• Anticoagulation therapy for 4 months resulted in the resolution of the internal carotid artery dissection.
• Residual symptoms of blepharoptosis and anisocoria were noted even after the dissection resolved.

Implications:

• This case highlights the importance of timely diagnostic imaging for suspected Horner syndrome to rule out emergent vascular conditions like ICAD.
• It underscores that spontaneous ICAD can occur even in the absence of typical risk factors or trauma, emphasizing the need for vigilance.
• Effective management involving anticoagulation can lead to favorable outcomes for ICAD, although long-term sequelae like persistent ptosis and anisocoria may occur.