Electrical cataract formation in the rabbit model.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
S R Hamiel
Publications and source records attributed to S R Hamiel.
Evaluation of the Hall-effect sensor for determination of eyelid closure in vivo.
A small device to detect eyelid closure was designed on the basis of a Hall-effect sensor. Accurate sensing of normal eyelid closure is required to develop a prosthetic eyelid closure device for patients with paralyzed orbicularis oculi muscles. In this study, six rabbits had the sensors surgically implanted. A Hall-effect sensor, a small device that measures magnetic fields, was implanted in the inferior eyelid near the ciliary margin. An opposing magnet was implanted in the upper eyelid. Thus, as the eyelid closes, the output of the Hall-effect sensor will increase. This output voltage was monitored weekly. During the first 5 weeks the output of the Hall-effect sensor decreased slightly but then reached a steady state for the duration of the experiment. This study suggests that the Hall-effect sensor could be used to detect normal eyelid closure in an implantable facial reanimation device.
Animals↗
Determination of palpebral closure using a Hall sensor magnet pair.
A small device that can detect eyelid closure was designed using a Hall sensor and magnet. The ability of the sensor to differentiate blinks from saccadic motion is of vital interest in development of a device to alleviate complications of facial nerve paralysis. Twelve physically normal human subjects were used in this study. A small Hall sensor (3 x 2.5 x 1.1 mm), a device that detects magnetic fields, was attached to the lower eyelid near the lid margin, and an opposing small magnet (3 x 2 x 1 mm) was attached to the upper eyelid, also near the lid margin. Output potentials from the Hall sensor were monitored during eye blinks and saccadic eye movements to correlate sensor potentials with eye movements. Results indicate that the Hall sensor is effective at determining palpebral closure and discriminating eye closure from other eye movements. Therefore, we conclude that the Hall sensor is a reliable means for determining palpebral closure and is ideally suited for use in a facial prosthesis that uses the normal blink as a trigger to reanimate the contralateral paralyzed eyelid.
Adult↗