Assessment of light reaction of pupil

[tkyeung]

In a normal situation, when a torch shines light on the pupil, the pupil constricts. If the torch is not moved away and continues to shine the pupil, what will happen to the pupil size?

[NICU Guy, BSN, RN]

It stays constricted, because the reason it constricts is to limit the amount of light coming into the eye. Bright day outside, the pupil will be small, dim room the pupil dilates to allow more light into the eye.

[tkyeung]

In the pupil assessment, the light reaction is classfied as reactive or non-reactive. If the light is shone, the pupil constrict. then it stays the same constricted size upon further shining, then the pupil is reactive, then non-reactive to light? i am a bit confused

[21strawberry]

You are over-thinking the reaction, it seems. The pupil is reactive or non-reactive based on the response to the light initially being shone on it. The pupil will not continue to react as the light shines, unless I suppose the light source was getting dimmer or brighter. I hope that helps.

[MrChicagoRN, RN]

In the pupil assessment, the light reaction is classfied as reactive or non-reactive. If the light is shone, the pupil constrict. then it stays the same constricted size upon further shining, then the pupil is reactive, then non-reactive to light? i am a bit confused

The "natural" state of the pupil in the absence of stimuli (light) is dilation

shine light, pupil reacts by constricting

reaction to steady light source is continued constriction

i learned to flick light to side and back to clearly see the reaction.

[tkyeung]

that means the light response is assessed during the moment/instant that the light is shone on the pupil?

[sapphire18]

that means the light response is assessed during the moment/instant that the light is shone on the pupil?

Yes. If a pupil ever changes size it is "reactive". It is only nonreactive or "fixed" if it stays the same size no matter what amount of light it is exposed to.

[Esme12, ASN, BSN, RN]

Is this for school?

[Here.I.Stand, BSN, RN]

We chart ours as "brisk," "sluggish," or "fixed," along with the size (pre-flashlight) and shape... but yes, it's based on what you see initially when you shine the light in their eye.

[tkyeung]

that means light reaction refers to the pupil reaction to a flash of light rather than to a persistent shining of light?

[akulahawkRN, ADN, RN, EMT-P]

You're very much overthinking this. Reactivity or non-reactivity is simply a measurement of the pupil's reaction to, or absence of light. Shine light in the eyes, pupils should constrict. Take the light away and they should dilate. As long as there's a steady state of presence or absence of light, the pupils should also remain in a steady state too.

[tkyeung]

shine light in the eyes pupil constrict, continue shine light is still shining light in the eyes, right? Pupil will be non-reactive?