What is a hippus?
Hippus, also known as pupillary athetosis, is spasmodic, rhythmic, but irregular dilating and contracting pupillary movements between the sphincter and dilator muscles. Pupillary hippus comes from the Greek hippos meaning horse, perhaps due to the rhythm of the contractions representing a galloping horse.
Does hippus go away?
Conclusions: Pupillary hippus can be extinguished by antagonizing the PNS, whereas agonizing the SNS dilates the pupil without affecting hippus.
Is pupillary hippus normal?
Pupillary hippus (PH) refers to spontaneous bilateral synchronous rhythmic constriction and dilatation of the pupils [1]. This rare phe- nomenon is spasmodic, cyclic and bilaterally in phase, and is usually considered benign [2].
What causes pupillary Athetosis?
Pupillary athetosis usually occurs physiologically in a drowsy state and can range from 0.04 to 2 Hz. It is pathologically associated with nonconvulsive status epilepticus, diabetic neuropathy, or myasthenia gravis.
What drugs cause hippus?
Drugs such as amphetamines, cocaine, atropine, and scopolamine can cause bilateral mydriasis. Severe anoxia is also associated with this finding. Hippus is a state of physiologic unrest.
What causes pupils to dilate and constrict rapidly?
Stimulation of the autonomic nervous system’s sympathetic branch, known for triggering “fight or flight” responses when the body is under stress, induces pupil dilation. Whereas stimulation of the parasympathetic system, known for “rest and digest” functions, causes constriction.
What is Adie’s tonic pupil?
Adie’s tonic pupil refers to a dilated, poorly reactive pupil, presumably from dysfunction of the ciliary ganglion behind the eye. The nerves responsible for pupil constriction connect through the ciliary ganglion.
What drug makes you go blind?
The consciousness-altering drug LSD is best known for its bizarre visual effects: even a small dose of the drug can turn the flat walls of your living room into something out of Wonderland.
