However, a large-scale investigation based on data of nearly 700 patients showed "that aspirin or other antiplatelet aggregating agents or anticoagulants adversely influence the visual outcome in patients with CRVO and hemi-CRVO, without any evidence of protective or beneficial effect". Several expert groups, including the Royal College of Ophthalmologists, recommended against the use of antithrombotic drugs (incl. aspirin) for patients with RVO. Central effects
Large doses of salicylate, a metabolite of aspirin, cause temporary tinnitus (ringing in the ears) based on experiments in rats, via the action on arachidonic acid and NMDA receptors cascade. Reyes syndrome
Reyes syndrome, a rare but severe illness characterized by acute encephalopathy and fatty liver, can occur when children or adolescents are given aspirin for a fever or other illness or infection. From 1981 to 1997, 1207 cases of Reyes syndrome in people younger than 18 were reported to the US Centers for Disease Control and Prevention (CDC). Of these, 93% reported being ill in the three weeks preceding the onset of Reyes syndrome, most commonly with a respiratory infection, chickenpox, or diarrhea. Salicylates were detectable in 81.9% of children for whom test results were reported.
Pathophysiology
It has been postulated that the synkinesis is due to damage to cranial nerve nuclei, caused by peripheral nerve injury and the nuclear lesion releases evolutionarily older [neural] mechanisms with their tendency toward associated movements, and so primitive reflexes are not inhibited.Marcus Gunn jaw-winking is an exaggeration of a very weak physiologic co-contraction that has been disinhibited secondary to a congenital brain stem lesion. The stimulation of the trigeminal nerve by contraction of the pterygoid muscles of jaw results in the excitation of the branch of the oculomotor nerve that innervates the levator palpebrae superioris ipsilaterally (on the same side of the face), so the patient  will have rhythmic upward jerking of their upper eyelid.There are two major groups of trigemino-oculomotor synkineses:
1) External pterygoid-levator synkinesis is when the eyelid raises upon:

Jaw thrust to opposite side (homolateral external pterygoid)
Jaw is projected forward (bilateral external pterygoid)
Mouth is opened widely2) Internal pterygoid-levator synkinesis is when the eyelid raises upon teeth clenching
External pterygoid-levator synkinesis is the more common group. Treatment
Treatment is usually unnecessary. In severe cases, surgery with a bilateral levator excision and frontalis brow suspension may be used. Inverse Marcus Gunn phenomenon
Inverse Marcus Gunn phenomenon is a rare condition that causes the eyelid to fall upon opening of the mouth. In this case, trigeminal innervation to the pterygoid muscles of the jaw is associated with an inhibition of the branch of the oculomotor nerve to the levator palpebrae superioris, as opposed to stimulation in Marcus Gunn jaw-winking. References


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