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EEG changes as an indication of central nervous system involvement following cyclopentolate 1% eye drops; a
Helena Maria van Minderhout1,2, Maurits Victor Joosse1, Erica Surya Klaassen3
1Department of Ophthalmology, Haaglanden Medical Centre, The Hague.
Insights
Cyclopentolate eye drops can affect the central nervous system (CNS), causing drowsiness and altered EEG patterns in children. Despite these effects, cyclopentolate-1% remains safe for pediatric use.
Area of Science:
- Neuroscience
- Ophthalmology
- Clinical Pharmacology
Background:
- Cyclopentolate is commonly used for cycloplegic refraction in children.
- Potential central nervous system (CNS) effects of topical cyclopentolate are not fully understood.
- Electroencephalography (EEG) can detect CNS activity changes.
Purpose of the Study:
- To compare EEG patterns after administering cyclopentolate versus placebo eye drops in children.
- To detect and assess CNS changes induced by cyclopentolate in pediatric subjects.
Main Methods:
- Prospective, randomized, placebo-controlled, double-blind pilot study.
- Healthy volunteers aged 6-15 years underwent EEG recordings before and after instillation of cyclopentolate-1% or placebo.
- EEG data analyzed for changes in power, synchrony, and presence of drowsiness/sleep.
Main Results:
- Cyclopentolate administration led to increased temporal Beta power and decreased parietal/occipital Alpha-2 power, indicating CNS uptake.
- Significant decreases in frontal Delta-1 power and overall frontal power, along with reduced activation synchrony, suggest CNS suppression.
- 64% of older children reported cognitive effects; 33% of all subjects showed drowsiness or sleep on EEG after cyclopentolate, not placebo.
Conclusions:
- Topical cyclopentolate-1% affects the CNS in children, manifesting as altered consciousness, drowsiness, and specific EEG pattern changes.
- EEG findings support cyclopentolate's potential action as a short-acting CNS depressant in pediatric populations.
- Despite CNS effects, cyclopentolate-1% is considered safe for use in children and young adolescents for ophthalmic purposes.
Abstract:
To compare EEG-patterns after instillation of cyclopentolate versus placebo eye drops. Prospective, randomized, placebo-controlled, and observational pilot study is presented. Ophthalmology outpatient clinic Dutch metropolitan hospital. Healthy 6- to 15-year-old volunteers with normal or low BMI requiring a cycloplegic refraction/retinoscopy. Randomized; 1 visit 2 drops cyclopentolate-1% and 1 visit 2 drops placebo (saline-0.9%). Single-blind: conducting researcher. Double blind: subjects, parents, clinical-neurophysiology staff, neurologist, and statistician. A 10-min baseline EEG-recording, drop-application, and follow-up to at least 45 min. Primary outcome: Detection of CNS changes, i.e. EEG-pattern changes, following two drops of cyclopentolate-1%. Secondary outcome: Determination of the extent of these pattern changes. Thirty-six cyclopentolate-1% saline-0.9% EEG registrations were made in 33 subjects; 18 males and 15 females. Three subjects were tested twice (interval 7 months). Nine out of fourteen (64%) of the 11- to 15-year-old children reported impaired memory, attention, alertness, as well as mind wandering following cyclopentolate. Drowsiness and sleep were seen in EEG-recordings of 11 subjects (33%) following cyclopentolate. We observed no drowsiness nor sleep during placebo recordings. The mean time to drowsiness was 23 min. Nine subjects arrived in stage-3 sleep but none arrived in REM-sleep. In subjects without sleep (N=24), significant changes compared to placebo-EEG were present for many leads and parameters. The main findings during awake eye-open recording were as follows: 1) a significant increase of temporal Beta-1,2 and 3-power, and 2) a significant decrease in: a) the parietal and occipital Alpha-2-power, b) the frontal Delta-1-power, c) the frontal total power, and d) the occipital and parietal activation synchrony index. The former finding reflects cyclopentolate uptake in the CNS, and the latter findings provide evidence for CNS suppression. Cyclopentolate-1% eye drops can affect the CNS and may cause altered consciousness, drowsiness, and sleep with concomitant EEG results in both young children and children in puberty. There is evidence that cyclopentolate has the potency to act as a short acting CNS depressant. Nevertheless, however, cyclopentolate-1% can safely be used in children and young adolescents.
