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Comparison of the effects of operating microscopes with light emitting diode and halogen light source on the eye: a
Bahri Aydın1, Armagan Ozgur2, Huseyin Baran Ozdemir1
1Medical School, Department of Ophthalmology, Gazi University, Ankara, Turkey.
Purpose:
To evaluate the potential toxicity of operation microscopes with halogen and light emitting diode (LED) light source on the rabbit eyes.
Materials And Methods:
Thirty-two eyes of 16 male New Zealand pigmented rabbits were involved in the study. The rabbits were divided into two groups according to the type of light source applied. Only one eye of each rabbit was exposed to illumination light, unexposed fellow eyes served as the control group. Experimental groups included group 1 exposed to halogen light for 2 h and evaluated 1 day and 1 week after the illumination, group 2 exposed to LED light for two hours and evaluated 1 day and 1 week after the illumination. On the first and seventh days after exposing the light, we evaluated the rabbit corneas using in vivo confocal microscopy (IVCM). At the end of the seventh day, the Hematoxylin-eosin staining and TUNEL staining were performed to investigate the presence of apoptosis in the retina and retina pigment epithelium.
Results:
Early IVCM findings revealed corneal epithelial cell ovalization and indistinct intercellular borders in the halogen light group. We also observed more increase in the keratocyte density index (23.7% vs 14.1%, p = 0.001, respectively) and the Bowman reflectivity index (12.4% vs 4.1%, p = 0.001, respectively) at first day of the light exposure in halogen light group compared to LED light group. However, late IVCM indicated that these findings disappeared one week later. No apoptosis was observed in the corneal and retinal layers in early and late examination groups.
Conclusion:
The present experimental study demonstrated that both halogen and LED lights, which were commonly used for microscopic eye surgery, had no sustained adverse effect on the cornea and retina of the rabbits; however, halogen light had a temporary adverse effect on corneal epithelium and stroma, which resolved within 1 week.
Insights
This study found that while both halogen and LED lights used in microscopic eye surgery caused temporary corneal changes in rabbits, neither light source resulted in lasting damage or apoptosis. Halogen light showed transient effects on the corneal epithelium and stroma.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Toxicology
Background:
- Microscopic eye surgery utilizes various light sources, including halogen and light-emitting diode (LED) technologies.
- Assessing the ocular toxicity of these light sources is crucial for patient safety during ophthalmic procedures.
Purpose of the Study:
- To evaluate the potential toxicity of halogen and LED light sources from operation microscopes on rabbit eyes.
- To compare the short-term and long-term effects of these light sources on ocular tissues.
Main Methods:
- The study involved 32 rabbit eyes, divided into two groups: one exposed to halogen light and the other to LED light for 2 hours.
- Corneal evaluations were performed using in vivo confocal microscopy (IVCM) at 1 day and 1 week post-exposure.
- Hematoxylin-eosin and TUNEL staining were used to assess apoptosis in retinal and retinal pigment epithelium layers at 1 week.
Main Results:
- Early IVCM revealed transient corneal epithelial cell ovalization and indistinct intercellular borders in the halogen group.
- The halogen group showed significantly higher keratocyte density and Bowman reflectivity indices compared to the LED group at day 1 (p<0.001).
- These corneal changes resolved within 1 week, and no apoptosis was detected in any ocular layer for either group.
Conclusions:
- Both halogen and LED lights used in microscopic eye surgery demonstrated no sustained adverse effects on rabbit corneas and retinas.
- Halogen light induced temporary adverse effects on the corneal epithelium and stroma, which were fully reversible within a week.
- The findings suggest that current microscopic illumination technologies are safe for ocular tissues with short-term exposure.
