Housecall. Pupil dilation test. If you have Horner syndrome, your pupil will open (dilate) slower than normal. Your doctor can evaluate this by placing drops of medication in your eye that force your pupil to dilate. The way the pupil responds to the eye drops will help confirm or deny a diagnosis of Horner syndrome. Follow-up tests. LEGAL CONDITIONS AND TERMS OF USE APPLICABLE TO ALL USERS OF THIS SITE. ANY USE OF THIS SITE CONSTITUTES YOUR AGREEMENT TO THESE TERMS AND CONDITIONS OF USE.

Horner syndrome.

Housecall.

. Pupil dilation test. If you have Horner syndrome, your pupil will open (dilate) slower than normal. Your doctor can evaluate this by placing drops of medication in your eye that force your pupil to dilate. The way the pupil responds to the eye drops will help confirm or deny a diagnosis of Horner syndrome. Follow-up tests. A physical exam and pupil dilation test can confirm a diagnosis of Horner syndrome.

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