Differential Diagnosis for Mild Unilateral Ptosis
- Single most likely diagnosis
- Horner's Syndrome: This condition is characterized by a classic triad of ptosis, miosis, and anhidrosis. It can be caused by a disruption in the sympathetic pathway and is often seen unilaterally. The mild ptosis associated with Horner's Syndrome makes it a likely candidate for this presentation.
- Other Likely diagnoses
- Third Cranial Nerve (Oculomotor) Palsy: This condition can cause ptosis due to weakness of the levator palpebrae superioris muscle. It may be associated with other symptoms such as diplopia and pupillary dilation.
- Myasthenia Gravis: An autoimmune disorder that can cause fluctuating weakness of the muscles, including those controlling eyelid movement. Ptosis may be unilateral or bilateral and can vary in severity throughout the day.
- Senile Ptosis: Age-related weakening of the levator palpebrae superioris muscle or its tendon, leading to drooping of the eyelid. It is more common in older adults and may be unilateral or bilateral.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Cavernous Sinus Thrombosis: A rare but potentially life-threatening condition that can cause ptosis as part of a broader spectrum of symptoms including headache, fever, and cranial nerve palsies.
- Aneurysm or Arteriovenous Malformation (AVM): Vascular abnormalities that can compress or damage the third cranial nerve, leading to ptosis. Prompt diagnosis is crucial to prevent further complications such as subarachnoid hemorrhage.
- Pituitary Apoplexy: Sudden hemorrhage or infarction of a pituitary tumor, which can compress surrounding structures including the third cranial nerve, causing acute ptosis.
- Rare diagnoses
- Chronic Progressive External Ophthalmoplegia (CPEO): A mitochondrial disorder that affects the external eye muscles, leading to progressive ptosis and ophthalmoplegia.
- Oculopharyngeal Muscular Dystrophy: A rare genetic disorder characterized by progressive ptosis and dysphagia.
- Leprosy: In rare cases, leprosy can cause unilateral ptosis due to involvement of the facial nerve or direct infiltration of the eyelid.