a computer simulation of the effects of drugs on the human eye to teach autonomic pharmacology
1David Dewhurst, 2Michael Lew, 2James Ziogas, & 1Stewart Cromar
The ‘Tutorial’ section describes, using text and animated schematic graphics, the sympathetic and parasympathetic control of pupil diameter and how pupil diameter changes in response to a change in ambient light intensity.
The ‘Student Exercise’ section provides information on how to work through the investigation on a virtual patient using a ‘normal’ patient as an illustration. Thus students have the opportunity to investigate how the normal pupil will respond to a change in ambient light intensity, investigate the blink reflex and text the action of a number of pharmacological agents. They are encouraged to measure the pupil diameter (using an on-screen cross-hair cursor) at a range of light intensities and to observe, for each eye, the speed with which the pupil diameter changes. They can also investigate the action of a number of pharmacological agents applied topically to the eye (single dose, enough for a large, but not maximal, response in eyes that are responsive) and record their observations on an on-screen chart. The agents available (atropine, pilocarpine, physostigmine, phenylephrine, cocaine, and amphetamine) all affect neurotransmission at the postganglionic sympathetic and parasympathetic synapses and have little effect on ganglionic transmission. There is also a ‘washout’ facility which instantly removes the applied drugs whereas in the real situation several hours might be required for some of the drug effects to be reversed.
The ‘Simulation’ section contains four virtual patients each suffering from a medical condition which results in an abnormal pupillary reflex in one eye:
first take measurements of the response to a change in light intensity
which should give a clue to the underlying problem. They can then investigate
this further by choosing two of the drugs from the list and observing
their effects - that is sufficient to test the best hypothesis for each
patient. To confirm their diagnosis students can then choose to administer
one more agent after which they will be expected to select a diagnosis
from the list.
Language Versions: English
Recommended System Requirements:
Target Audience: Particularly suitable for undergraduate students from a range of biological science, medical and health-related courses.
Price: £250 (multiuser, educational license)
Price: £399 (multiuser, non-education licence)
1College of Medicine & Veterinary Medicine, University of Edinburgh, 15 George Square, Edinburgh EH8 9XD, UK & 2Dept. of Pharmacology, University of Melbourne
Click on one of the above screen grabs to see full size image.