Differential Diagnosis for Vertical Diplopia in One Eye
Single Most Likely Diagnosis
- Monocular Vertical Diplopia due to Refractive Error: This condition occurs when there is an abnormality in the way the eye focuses light, leading to the perception of two images, one above the other, in one eye. This can be caused by conditions such as cataracts, astigmatism, or irregularities in the cornea or lens.
Other Likely Diagnoses
- Monocular Diplopia due to Retinal Conditions: Certain retinal conditions, such as epiretinal membrane or retinal detachment, can cause monocular diplopia by distorting the retina and affecting the way visual information is processed.
- Optic Nerve Conditions: Conditions affecting the optic nerve, such as optic neuritis or optic nerve tumors, can cause monocular diplopia by disrupting the transmission of visual signals from the eye to the brain.
- Ocular Motor Dysfunction: Weakness or paralysis of the extraocular muscles can cause vertical diplopia, although this typically presents as binocular diplopia. However, in some cases, the brain may adapt, and the diplopia may be perceived in only one eye.
Do Not Miss Diagnoses
- Giant Cell Arteritis: This is an inflammatory condition that can cause sudden, severe vision loss and may present with monocular diplopia. It is essential to consider this diagnosis due to its potential for severe and irreversible vision loss if not promptly treated.
- Brain Tumors or Aneurysms: Although less common, brain tumors or aneurysms affecting the visual pathway can cause monocular diplopia. These conditions require urgent medical attention due to their potential for severe consequences, including vision loss and neurological deficits.
Rare Diagnoses
- Cranial Nerve Palsies: While typically causing binocular diplopia, cranial nerve palsies (III, IV, or VI) can, in rare instances, present with monocular diplopia due to complex adaptations in the brain's processing of visual information.
- Sjögren's Syndrome: This autoimmune disorder can cause inflammation in the eyes, leading to monocular diplopia among other ocular symptoms. It is a rare cause but should be considered in patients with a history of autoimmune diseases.