Biomedical engineering project creates eyes that will never tire

Nov 24 2004

A pair of eyes that follow you around the room is normally the hallmark of a successful portraitist. Tim Nelson, however, is working to achieve a similar effect by employing a pair of disembodied, robotic eyes.

His aim is to help medical students to master the nuances of eye examinations.

Mr Nelson, an honours biomedical engineering student at Flinders University, Australia, has spent the last year working on a project that aims to give medical students training in conducting eye tests by creating a pair of robotic eyes that mimic the responses of real patients.

Mr Nelson said the ophthalmic simulator, known as EyeSim, comprises a sophisticated system that links printed circuits and computer software with robotics.

The eyes contain a “fake iris” programmed to reproduce the constriction and dilation of the pupil when exposed to varying strengths of light.

When required to follow a light source, the eyes use images provided by an internal webcam, swivelling in their armatures to track the movement.

At the moment, the eyes rely on manual operation from the computer console to follow a light source, but as the project is developed, it is intended that this will become a fully automated function. The eyes will also acquire a more natural aspect by being mounted in a false human head.

Mr Nelson said that EyeSim had the benefit of making learning “risk-free” for students and patients. And as well as sparing patients who may be distressed or nervous the attentions of inexperienced medical students, EyeSim ultimately will be able to present a range of symptoms indicative of conditions and deficits that students may never experience in the course of their clinical training.

“It also gives the students the benefit of repeatability,” Mr Nelson said.

The system enables students to redo tests until they are confident in their technique, and provides them with almost instantaneous feedback and assessment.

As an individual student’s confidence grows, EyeSim will also allow lecturers to introduce increasing clinical variations and levels of complexity.

The project is the latest in a series of medical simulators being developed by Professor Harry Owen of Flinders University’s Department of Anaesthesia and Pain Medicine and Associate Professor Karen Reynolds of the School of Informatics and Engineering.

The University’s Clinical Skills and Simulation Unit has a state-of-the-art suite of simulators and manikins capable of imitating a wide range of injuries and illnesses, and allowing students to learn a range of fundamental procedures without risk to patients.

The collaboration between Professor Owen and Associate Professor Reynolds has already resulted in two simulators of its own, one which trains students in the application of cricoid pressure (an essential step in anaesthetics intubation), and another which provides realistic training in the administration of epidural injections.

Both were developed as projects by biomedical engineering students and are now being promoted by Flinders MediTech, a spin-off company set up for commercialisation of the medical training devices.

Part of the project’s intention was to demonstrate the feasibility of an eye simulator to potential manufacturers.

Mr Nelson said that establishing the brief, working with different centres of relevant expertise around the University and overcoming various practical obstacles had been an invaluable preparation for future employment.

“It was an exercise in taking something theoretical and turning it into something practical, and I’ve learned a lot,” Mr Nelson said.

“It’s still a work in progress, but I’ve had great satisfaction in getting it off the ground.”

His efforts have already been rewarded with the Institute of Electrical and Electronic Engineers (SA Branch) annual student papers presentation prize, and the Engineers Australia/ Australasian College of Physical Sciences and Engineers in Medicine Prize for a postgraduate seminar in biomedical engineering or medical physics.

He also won the Society for Medical and Biological Engineering prize for best biomedical engineering project at the annual Flinders University Engineering Expo.