We absolutely love the ease and convenience of shopping for deals online; however, when it comes to glasses, it’s not so simple. Glasses must be custom-made to your prescription and facial measurements. Since they are Class I medical devices, they must also meet ANSI (American National Standards Institute) and ISO (International Organization for Standardization) requirements, which are rarely regulated online. So, when patients ask for our opinions on purchasing online, we warn them of the following dangers.
Prescription Issues. Glasses must be made accurate to the prescription, with acceptable limits of error. Not only must the strength be right, but the center of the lens must also sit in front of the eye’s pupil. This relies on having a correct pupillary distance (PD) measurement. A PD that is off by even 1 mm can create ‘prismatic effects’ which change the prescription. This can lead to eyestrain, headache, blur, and double vision. In a Canadian study assessing popular online retailers, 81% of glasses had the wrong prescription.
Fit Issues. Frames should never squeeze your temples, leave uncomfortable imprints on your nose, sit too close or too far, fit too wide or narrow, tilt at an odd angle, or slip down your face. Their shape should complement and enhance your face. And these days, a trendy pair of glasses are a fashion statement! Virtual fitting simply does not compare to trying on frames in-store, with the input and advice from a certified optician or optometrist. 70% of frames purchased online do not meet basic comfort and position criteria.
Safety Issues. All lenses must meet a minimum thickness for safety reasons. In cases where shatter-resistance is required, these standards are even more strict – the lenses must be even thicker and only certain lens materials provide maximum protection. Again, there is no guarantee of these standards being met by online retailers. One study showed that 23% of eyewear ordered online failed impact testing, compared to <0.5% failure rate for lenses produced by ophthalmic labs that undergo regular inspection.
Coating Quality Issues. There are many different types of anti-reflective, scratch-resistant, and blue light coatings. Low-quality coatings damage easily, and are also much harder to clean. Everyone knows how frustrating it is to constantly clean dirty fingerprint-covered lenses! Ordering online also does not guarantee that you get what you ask for – many lenses end up being sent with missing coatings.
Accountability Issues. We strongly believe that you should never be stuck with a pair of glasses that you can’t use. If something goes wrong with either the prescription or frame, it’s important that there is someone who can help problem-solve through the issue. Your glasses should have a dependable warranty that includes the ability to change the prescription if you are unable to adapt to it.
The bottom line? Protect yourself by ensuring that your glasses have been inspected to meet medical standards. We encourage ordering your glasses from a reputable retailer with a physical store and trained staff. When it comes to vision, it is well worth investing in glasses with high-quality materials and coatings so that you can see your best.
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Written by: Dr. Natalia Fong
Photo Credit: Photo by John Schnobrich
References:
https://optometrists.sk.ca/wp-content/uploads/2016/08/OnlineEyewearEvaluation.pdf
https://www.ncbi.nlm.nih.gov/pubmed/21871395