Unilateral mydriasis in a child with a ventriculoperitoneal shunt for obstructive hydrocephalus: a diagnostic dilemma

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.

Sudden anisocoria in a healing pediatric multitrauma patient

“…3 Anisocoria also has been reported in children, including a similarly complicated case of a 3-year-old with a ventroperitoneal shunt. 4 However, given the case patient's combination of an extensive multitrauma history and enhanced sensitivity to radiation (common in children), this case further highlights the need for a standardized approach to the evaluation of isolated anisocoria, particularly in the ICU.…”

Acute perioperative neurological emergencies

“…Unilateral mydriasis can also be caused by anesthetic agents, stellate ganglion block, impaired venous return from head and neck, or unintentional application of alpha-adrenergic or anticholinergic agents. [22][23][24] As neurological assessment is difficult during and immediately after anesthesia, it is important to monitor pupil size and reactivity perioperatively.…”

“…These can be due to cerebral edema in steep Trendelenburg position, 21 spontaneous hemorrhagic stroke, or total spinal anesthesia. Unilateral mydriasis can also be caused by anesthetic agents, stellate ganglion block, impaired venous return from head and neck, or unintentional application of alpha-adrenergic or anticholinergic agents 22–24 …”

Drugs that act on the respiratory tract

“…The cardiovascular safety of long-acting muscarinic antagonists (LAMAs) were recently evaluated in two large meta analyses ( Lee et al, 2020 [M]; Yang, Zhang, et al, 2020 [M]). A case report describes an ocular side-effect associated with nebulized ipratropium therapy ( Banerjee et al, 2020 [A]). The safety of tiotropium in pediatric patients was also recently evaluated in both a systemic review and a meta-analysis ( Sunther et al, 2021 [M]; Yang, Peng, et al, 2020 [M]).…”

“…A case report from the United Kingdom describes nebulized ipratropium bromide associated with the development of mydriasis of the left eye of a young boy ( Banerjee et al, 2020 [A]). A 3-year-old boy presented with anisocoria (unequal pupils) following treatment of acute respiratory distress with nebulized ipratropium.…”