What causes unilateral mydriasis?
Benign episodic unilateral mydriasis (BEUM) is an isolated cause of intermittent pupil asymmetry that might be caused by hyperactivity of the sympathetic nervous system or hypoactivity of the parasympathetic system. An association between BEUM and migraine has been suggested in the literature.
How long does benign episodic unilateral mydriasis?
The median duration and frequency of events were 12 hours and two to three per month, respectively. Most patients did not identify any factor that could precipitate an occurrence. The most common associated symptoms during an episode included visual blur in 15 patients, headache in 9, and orbital pain in 5.
Why would one pupil suddenly be larger than the other?
If a person’s pupils are suddenly different sizes, it is best to seek medical attention. While not always harmful, a sudden change can indicate serious and dangerous medical conditions. It is especially important to seek medical attention if the change occurs after an injury or with other symptoms.
Can migraines cause different pupils?
That kind of difference in the size of the pupil — a phenomenon known as anisocoria — could be seen in people with migraines, the doctor told the anxious woman.
What causes a coloboma?
Coloboma arises from abnormal development of the eye. During the second month of development before birth, a seam called the optic fissure (also known as the choroidal fissure or embryonic fissure) closes to form the structures of the eye. When the optic fissure does not close completely, the result is a coloboma.
What is the difference between miosis and mydriasis?
Miosis can occur in one or both eyes. When it affects only one eye, it’s also called anisocoria. Another name for miosis is pinpoint pupil. When your pupils are excessively dilated, it’s called mydriasis.
What is benign episodic unilateral mydriasis?
The features of our patient were consistent with a rare but innocuous condition termed ‘benign episodic unilateral mydriasis.’ 2 The affected individuals, usually women, often have a history of migraine. 2 The episodes may be accompanied by blurred vision, orbital pain, headache, or photosensitivity. 2 The dilated pupil is the only ocular finding.
What are the signs and symptoms of unilateral mydriasis?
Over the next 2 years, this patient presented four times with similar episodes of unilateral mydriasis, twice affecting the left eye ( Figure 1b ). Three of these episodes were accompanied by headache and two by ocular pain. Each time there were no other significant findings and pharmacological tests were negative. Episodic unilateral mydriasis.
As with miosis, mydriasis can be pharmacologically induced with agents such as atropine. However, unlike miosis, mydriasis is associated with many conditions.
Does cocaine cause unilateral mydriasis (anisocoria)?
Unilateral mydriasis (anisocoria), suggesting serious neurological injury, has been attributed to topical cocaine [467 ]. A 51-year-old man developed mydriasis in one eye, with loss of the accommodation reflex, immediately after endoscopic sinus surgery, before which 4% cocaine had been applied to the nasal mucosa on cotton pledglets.
