Pupillary hippus, also known as pupillary athetosis, is spasmodic, rhythmic, but regular dilating and contracting pupillary movements between the sphincter and dilator muscles. [1] [2] Pupillary hippus comes from the Greek hippos meaning horse, perhaps due to the rhythm of the contractions representing a galloping horse. [3]

In this study we aimed to determine the roles of the SNS and PNS in pupillary hippus by pharmacologic means. Participants received either a PNS antagonist (tropicamide) or a SNS agonist (phenylephrine) to dilate their pupil.

In the absence of changes in external influences such as luminance, mood, and fixation, the pupil is in constant motion. An exaggeration of this phenomenon is usually termed Pupillary Hippus: its frequency ranges from 0.04 to 2 Hz , and the magnitude of the pupil size variations usually do not surpass 0.5 mm .

Even when there is no direct external stimulation, the size of the pupil tends to spontaneously change. Such spontaneous pupil-size fluctuations are sometimes called hippus or pupillary unrest. Hippus is generally used to describe periodic fluctuations, whereas pupillary unrest is a more general term that refers to any kind of spontaneous ...

2018年9月23日 · Pupillary hippus (PH) refers to spontaneous bilateral synchronous rhythmic constriction and dilatation of the pupils . This rare phenomenon is spasmodic, cyclic and bilaterally in phase, and is usually considered benign .

2019年10月10日 · Hippus is the normal rhythmic pupillary oscillation commonly seen when light stimulates either eye. Both pupils oscillate in synchrony, and the amplitude and frequency vary ( Table 12.2). Changes in the pupil innervation will produce dilation or constriction of the pupil.

It has been around a long time and refers to a restless mobility of the pupil, a tendency for the pupil size to fluctuate and to bounce up and down when you expect it to be stable. The word is related to the Greek hippos, a horse, and one is tempted to assume that it is an allusion to some jogging equestrian motion.

2017年1月1日 · Pupillary hippus can be extinguished by antagonizing the PNS, whereas agonizing the SNS dilates the pupil without affecting hippus. This suggests that hippus originates from central PNS activity, and not from SNS activity, or oscillations in the balance between PNS and SNS at the pupil.

Pupillary hippus as clinical manifestation of refractory autonomic nonconvulsive status epilepticus: Pathophysiological implications Seizure . 2018 Dec:63:102-104. doi: 10.1016/j.seizure.2018.11.006.

What is Hippus? Rhythmic constriction and dilation of the pupil. Can be easily observed when light is shined on eyes Hippus is however independent of light Often likened to a person dancing or a horse galloping Rhythmic Physiological or Pathological: Physiological but can be both