Portable and programmable clinical EOG diagnostic system

Monitoring eye movements is clinically important in diagnosis of diseases o f the central nervous system. Electrooculography (EOG) is one method of obt aining such records which uses skin electrodes, and utilizes the anterior p osterior polarization of the eye. A new EOG diagnostic system has been deve loped that utilizes two off-the-shelf portable notebook computers, one proj ector and simple electronic hardware. It can be operated under Windows 95, 98, NT, and has significant advantages over any other similar equipment, in cluding programmability, portability, improved safety and low cost. Especia lly, portability of the instrument is extremely important for acutely ill o r handicapped patients. The purpose of this paper is to introduce the techn iques of computer animation, data acquisition, real time analysis of measur ed data, and database management to implement a portable, programmable and inexpensive contacting EOG instrument. It is very convenient to replace the present expensive, inflexible and large-sized commercially available EOG i nstruments. A lot of interesting stimulation patterns for clinical applicat ion can be created easily in different shape, time sequence, and colour by programming in Delphi language. With the help of Winstar (a software packag e that is used to control I/O and interrupt functions of the computer under Windows 95, 98, NT), the I/O communication between two notebook computers and A/D interface module can be effectively programmed. In addition, the ne w EOG diagnostic system is battery operated and it has the advantages of lo w noise as well as isolation from electricity. Two kinds of EOG tests, purs uit and saccade, were performed on 20 normal subjects with this new portabl e and programmable instrument. Based on the test result, the performance of the new instrument is superior to the other commercially available instrum ents. In conclusion, we hope that it will be more convenient for doctors an d researchers to do the clinical EOG diagnosis and basic medical science re search by using this new creation.