Can contact lenses do more than just correct sight? Perhaps extend our healthspan?
Image credit: https://www.pexels.com/photo/white-magnifying-glass-on-blue-table-5843417/
- correcting vision by:
- correcting refractive error
- correcting the presbyopia (inability to focus close objects)
- correcting the color deficiencies
- cosmetics (changing the eye color)
- protection and recovery (therapeutic lenses, lens bandages)
- Delivering healthspan or lifespan drugs to the eyes
- Non-invasive measurement of glucose levels
- Glaucoma progression-monitoring contact lens
- Telescopic/zooming contact lens to treat visual impairments
- Smart contact lenses with a camera to help blind people
Non-invasive measurement of glucose levels
The product idea
The underlying mechanism
- Non-enzyme system
- Easy to use
- Does not impact the vision
- 15 to 30 min time delay of the tear fluid level after glucose is transported from the blood level
Lin YR, Hung CC, Chiu HY, et al. Noninvasive Glucose Monitoring with a Contact Lens and Smartphone. Sensors (Basel). 2018;18(10):3208. Published 2018 Sep 22. doi:10.3390/s18103208
Lane JD, Krumholz DM, Sack RA, Morris C. Tear glucose dynamics in diabetes mellitus. Curr Eye Res. 2006 Nov;31(11):895-901. doi: 10.1080/02713680600976552. PMID: 17114114.
Glaucoma progression-monitoring contact lens
- sensor - a soft contact lens (Figure 1.)
- antenna - placed around the eye, receives the wireless signal from the lens
- portable recorder - stores the information
Dunbar GE, Shen BY, Aref AA. The Sensimed Triggerfish contact lens sensor: efficacy, safety, and patient perspectives. Clin Ophthalmol. 2017;11:875-882. Published 2017 May 8. doi:10.2147/OPTH.S109708
Delivering healthspan or lifespan drugs to the eyes
Kim, Joohee, Eunkyung Cha, and Jang‐Ung Park. "Recent advances in smart contact lenses." Advanced Materials Technologies 5.1 (2020): 1900728.
Contact lenses and the risk of eye infections and diseases
Cheng, Kam H., et al. "Incidence of contact-lens-associated microbial keratitis and its related morbidity." The Lancet 354.9174 (1999): 181-185.
Szczotka-Flynn, Loretta B., Eric Pearlman, and Mahmoud Ghannoum. "Microbial contamination of contact lenses, lens care solutions, and their accessories: a literature review." Eye & contact lens 36.2 (2010): 116.
Telescopic/zooming contact lens to treat visual impairments
Eric. J. Tremblay, Igor Stamenov, R. Dirk Beer, Ashkan Arianpour, and Joseph E. Ford, "Switchable telescopic contact lens," Opt. Express 21, 15980-15986 (2013)
Smart contact lenses with a camera to help blind people
Silicone hydrogel contact lenses as detectors of organic solvents
- although soft contact lenses absorb up to 90 times more trichloroethylene and xylene than physiologic saline, the concentrations of the chemicals released into the tear saline were low compared to direct exposure. Chemicals were primarily released into the air .
- lenses also protected the cornea from strong acids .
- contact lenses could be used as a standard company's personal protective equipment (PPE) .
- contact lenses could protect eyes from volatile agents .
- Lenses didn't worsen the effect of volatile solvents.
- Protection of the eyes depends on the chemical, but in the case of acetic acid, n-butylamine, acetone, and few others, it seems to be better to wear them than not.