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"Child's pupil size varies constantly. Is this a problem?"

ZocdocAnswersChild's pupil size varies constantly. Is this a problem?


My son has an abnormal eye pupil. His both eyes pupil size is small but after few mins it increases to 50% of iris(approx 4 times larger). Again after sometime it reduces to normal size. This is happening from born. He is 4 now. Is it some problem?


The normal function of the eye pupil is that it dilates in response to low light situations. This allows more light to enter the eye and helps with visual acuity in dark environments. If you notice that your son's pupils dilate mostly in this setting, then there is probably nothing wrong. However, this is definitely an issue that you should mention to your son's pediatrician. Sometimes, pupil irregularities can be a sign of a serious medical problem, either a problem within the eye itself, or a problem with the neurological symptom. This is especially the case if the issue affects only one eye, rather than both eyes, raising the chance that this might be a medical problem. Your pediatrician will begin by examining your son's eyes closely. First, they will want to check for visual acuity, to make sure that your son's vision is basically normal. They will also look for any evidence of inflammation in the eye, cataracts, tumors, or other causes within the eye itself. Finally, they will perform a neurological examination, to make sure that there are no warning signs. Based on what they find, they may want to refer your son to an eye doctor for a more complete eye examination. Good luck!

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