Autonomic Pharmacology

Reactivity to Light

Test a patient's responses to altered light levels by:

Moving the sliding bar to change the ambient light intensity. You should use the cross-hair to measure the pupil diameter in mm at a mid-range intensity, a dim light intensity and a high-light intensity.
Testing the blink reflex and observe, for each eye, the speed with which the pupil diameter changes.

Note that each patient has, at most, one eye that is abnormal and so you should look particularly at any asymmetry in the responses. Also note any visual changes such as reddening.

Record your observations using the on-screen chart and then try to decide which eye is faulty and whether the fault lies in the sympathetic or parasympathetic nerves. This will be your hypothesis or interim conclusion.

Exercise 1 - Reactivity to Light

Ms Normal

Ambient Light

1. What do you observe initially and what questions might you ask? Use the blink button to help with your initial observations (e.g. pupillary response speed, discoloration and asymmetry).

2. Test the pupillary response to altered light conditions and measure the pupil diameter using the crosshair, e.g. 16 units.

	Right	Left
Dim
Mid
High

3. Which eye do you consider to be the problem?

4. Indicate which nervous system might be involved in any problem.