![]() ![]() Despite previous evidence reporting pupil constriction to the perception of motion, and the positive valence associated with symmetry, these experiments show that pupil dilation occurs during the perception of illusory motion. Although a reduction in perceived illusory motion did not produce a reduction in pupil dilation, removal of the illusory motion did. As a follow-up, we manipulated the RAP stimuli to reduce and then remove the illusion to determine (a) whether it was the asymmetry per se that induced the pupil dilation and (b) whether the amount of pupil dilation was contingent on the amount of observed illusory motion. All participants reported the perception of motion in the RAP condition and showed significantly greater pupil dilation to these stimuli as compared with viewing stimuli in the SP condition. In three experiments investigating pupil-size changes to peripheral drift, pupil response differences were observed between symmetric patterns (SPs) that elicited no impression of motion and repeated asymmetric patterns (RAPs) that did. We aimed to determine whether pupil dilation occurs during the perception of illusory motion. ![]() Therefore, the incidence of ipratropium bromide-induced anisocoria may increase.Peripheral drift is a specific type of illusory motion that causes observers to perceive motion in a static image. Failure of the dilated pupil to constrict after instillation of 1% of pilocarpine hydrochloride confirms the diagnosis.Īdministration of ipratropium bromide via a mask attached to a noninvasive BiPAP ventilator has become increasingly popular with the frequent use of noninvasive ventilation techniques. Other manifestations of ipratropium exposure include bilateral mydriasis, cycloplegia, blurred vision, dry eyes, and in rare cases, acute glaucoma ( 7). The anisocoria usually resolves within 48 hours of removal of the agent but sometimes may last up to 3 weeks ( 6) after the aerosolized bronchodilator is stopped. Contamination of the eye from nebulized ipratropium bromide leads to asymmetric pupillary dilation by paralyzing the parasympathetic nerve endings. Ipratropium bromide, which is used frequently as a bronchodilator in patients with bronchospasm, is a quaternary amine derivative of atropine and a direct antagonist at muscarinic cholinergic receptors ( 5). Most cases have since been described among children because of the difficulty in maintaining a properly fitted mask during delivery of respiratory treatments ( 4). Ipratropium bromide was not considered a cause of anisocoria until 1986 when Samaniego and Newman ( 3) described the first case. Atropine, scopolamine, and spray perfumes containing belladonna are well known to cause pharmacologic pupillary dilation by direct or indirect contamination of the eye. Because the face mask was malpositioned, the agent leaked outtoward the right eye.Īnisocoria is an alarming physical sign, leading most of the time to an extensive neuroradiologic investigation to rule out life-threatening conditions such as cerebral neoplasm, expanding aneurysm, or intracranial bleeding ( 1,2). Mydriatic right pupil in patient fitted with a face mask delivering aerosolized ipratropium bromide. The anisocoria resolved within 24 hours after discontinuation of the ipratropium bromide and adjustment of the face mask. The BiPAP face mask was found to fit imperfectly and to leak to the right ( Fig. Further review disclosed that he had received nebulized albuterol and ipratropium bromide via a face mask that was attached to the noninvasive BiPAP ventilator. Results of emergency brain CT were normal. No other abnormalities were noted on neurologic examination. During morning rounds, his right pupil was found to be fixed and dilated. Twenty-four hours later, he developed acute hypercapnic respiratory failure that required noninvasive ventilation with bilevel positive airway pressure (BiPAP). Physical examination on admission showed a distended abdomen with absent bowel sounds. We report such an occurrence.Ī 52-year-old man with chronic obstructive pulmonary disease and depression was transferred to our institution for further management of a biliary leak due to laparoscopic cholecystectomy. ![]() Transient anisocoria caused by aerosolized ipratropium bromide from an ill-fitting face mask is apparently a well-described entity ( 1-7), but is still not immediately recognized. ![]()
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