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Updated: Aug 17, 2026

Optic Nerve Transection: A Model of Adult Neuron Apoptosis in the Central Nervous System
Published on: May 12, 2011
The blepharocardiac reflex
Abstract:
The oculocardiac reflex is described as the triad of bradycardia, nausea, and faintness evoked by the stretching of ocular muscles, or by pressure on or within the eyeball. The trigeminal nerve is the afferent limb of this reflex; the efferent limb is the vagus nerve to the heart. This reflex was noted to occur from traction on the levator aponeurosis in five of 36 patients with ptosis, and from traction on the retractors of the lower eyelid in three of 11 patients with entropion. To our knowledge, this is the first documentation of eliciting this reflex by stretching the muscles of the eyelid. Electrocardiogram monitoring for early recognition of these cases, and the availability of an intravenous line with atropine for prompt treatment are strongly recommended. Careful manipulation of the upper and lower eyelid retractors and preoperative atropine therapy may help to reduce the incidence of this reflex.
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