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Biomedical subjects

Byunghun Choi

Publications and source records attributed to Byunghun Choi.

2 recordsLinked to original sources

The development of a nonintrusive home-based physiologic signal measurement system.

This paper describes the development of a nonintrusive health-monitoring house system that has been developed for monitoring patients' health status. The system functions unobtrusively and leaves patients free to conduct daily activities. Installed sensors and devices in the house monitor biosignals such as bedside electrocardiogram (ECG), snoring, weight, and movement pattern. The network in the house was constructed using asymmetric digital subscriber line (ADSL) and Bluetooth technologies and it is capable of transmitting monitored signals to the remote hospital server through the home server. The system is found to be effective in monitoring patients' daily activity and health status in a nonconstraining manner.

Adult↗

Development of pupillography using image processing.

PURPOSE: Pupillary examination is an important objective method to diagnose lesions of the anterior visual pathways. However, errors and faults may easily alter the interpretation and value of the test as it is highly dependent on the examiner's skills. Therefore, we tried to develop a pupillography which is independent of the examiner. METHODS: Hardware composed of a binocularly measuring instrument adapted for an infrared charge coupled device (CCD) was developed. Two arrays of infrared light emitting diodes (LED) were supplied in front of each of the subject's eyes. A microcontroller to modulate these LED was developed, as was software to save and analyze the pupil images. The hardware was able to deliver a light to either eye or to both eyes, and to change the time, frequency, and intensity of the stimulus. The software automatically analyzed the pupil size and location by image processing. Pupil size was calculated continuously. After artifact elimination, the response amplitudes of the pupils were determined for the right and left pupils. RESULTS: Pupillary images of size 320 x 240, at 30 frames/second, were saved and processed to evaluate the change of the actual pupil size and the velocity of pupillary response. CONCLUSIONS: A pupillography to measure, save and analyze the pupillary response using image processing was developed. Further detailed clinical studies with a large number of patients will be required to validate this new method.

Diagnostic Techniques, Ophthalmological↗