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Published on: October 14, 2022
Unilateral mydriasis in a child with a ventriculoperitoneal shunt for obstructive hydrocephalus: a diagnostic dilemma
Monidipa Banerjee1, Eiman Haj Ahmed1, Kathryn Foster1
1Department of Paediatrics, Ysbyty Gwynedd, Bangor, UK.
Insights
Sudden unilateral mydriasis in a child with a VP shunt was caused by ipratropium bromide nebulizer treatment. This reversible adverse effect highlights the need to consider medication side effects in diagnosis.
Area of Science:
- Pediatric Neurology
- Pharmacology
- Ophthalmology
Background:
- Unilateral mydriasis can indicate serious conditions like transtentorial uncal herniation.
- Ventriculoperitoneal (VP) shunts are used to treat obstructive hydrocephalus in children.
- Pharmacological causes of anisocoria (unequal pupil size) must be considered in differential diagnoses.
Observation:
- A 3-year-old boy with a VP shunt for hydrocephalus developed acute respiratory distress.
- During nebulizer treatment, he presented with unilateral mydriasis and absent light reflex.
- Initial CT scan showed no new intracranial abnormalities.
Findings:
- The condition was diagnosed as pharmacological anisocoria, specifically ipratropium-induced.
- Symptoms resolved completely within 24 hours after discontinuing ipratropium bromide.
- This is a rare presentation in a child with a VP shunt.
Implications:
- Clinicians must urgently evaluate unilateral mydriasis, considering both life-threatening conditions and medication side effects.
- Ipratropium bromide, especially via ill-fitting masks, can cause reversible anisocoria in children.
- This case underscores the importance of a thorough medication history in pediatric neurological emergencies.
Abstract:
There are several causes for sudden onset unilateral mydriasis, however impending transtentorial uncal herniation needs to be ruled out. This unique case highlights an uncommon adverse response to a common mode of treatment that leads to a diagnostic dilemma. A 3-year-old boy with a ventriculoperitoneal (VP) shunt for an obstructive hydrocephalus presented with an acute respiratory distress. He developed unilateral mydriasis with absent light reflex during treatment with nebulisers. An urgent CT scan of the brain did not show any new intracranial abnormality. A case of pharmacological anisocoria was diagnosed that resolved completely within 24 hours of discontinuation of ipratropium bromide. Although ipratropium-induced anisocoria has been reported in children, but to our knowledge none in a child with VP shunt for hydrocephalus. This emphasises the urgency in evaluating unilateral mydriasis to rule out life-threatening conditions. Clinicians should remember that ipratropium administered through ill-fitting face masks could cause this completely reversible adverse effect.
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