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Converting a conventional wired-halogen illuminated indirect ophthalmoscope to a wireless-light emitting diode
Mihir Kothari1, Kedar Kothari, Sanjay Kadam
1Department of Clinical Optics and Biomedical Engineering, Jyotirmay Eye Clinic, Ocular Motility Laboratory, Thane, India.
Aim:
To report the "do it yourself" method of converting an existing wired-halogen indirect ophthalmoscope (IO) to a wireless-light emitting diode (LED) IO and report the preferences of the patients and the ophthalmologists.
Subjects And Methods:
In this prospective observational study, a conventional IO was converted to wireless-LED IO using easily available, affordable electrical components. Conventional and the converted IO were then used to perform photo-stress test and take the feedback of subjects and the ophthalmologists regarding its handling and illumination characteristics.
Results:
The cost of conversion to wireless-LED was 815/- rupees. Twenty-nine subjects, mean age 34.3 [formula in text] 10 years with normal eyes were recruited in the study. Between the two illumination systems, there was no statistical difference in the magnitude of the visual acuity loss and the time to recovery of acuity and the bleached vision on photo-stress test, although the visual recovery was clinically faster with LED illumination. The heat sensation was more with halogen illumination than the LED (P = 0.009). The ophthalmologists rated wireless-LED IO higher than wired-halogen IO on the handling, examination comfort, patient's visual comfort and quality of the image. Twenty-two (81%) ophthalmologists wanted to change over to wireless-LED IO.
Conclusions:
Converting to wireless-LED IO is easy, cost-effective and preferred over a wired-halogen indirect ophthalmoscope.
