On a humid afternoon a few days ago, I was seated in my black swivel chair at my study table. My mind was just wandering as I pondered the events that had occurred in the entirety of 2021 and the first week and a half of 2022. What an adventure it has been. As I sat down and glanced around my bedroom, I noticed my glasses lying on the surface of the table. It is one of the few items I absolutely cannot live without.
My journey with glasses began when I was a Primary Three student. Despite being positioned at one of the first few rows in the classroom, I needed to squint to accurately note the fine details that lay on the whiteboard. It did not help that sometimes, the teachers’ handwriting would be quite tiny.
My dad realised that I needed glasses, and I had my first ever pair of prescription glasses made when I was Primary Three. I was officially diagnosed with myopia.
Myopia is better known as short-sightedness. Its pathophysiology is characterised by abnormally increased ocular axial length, or less commonly, by actual increased refractive power (either at the level of the cornea, or the natural lens embedded within the eye). In either case, the resulting focal point becomes anterior to the retina. For human beings to see a clear image, the resulting focal point should correspond nicely to the retina’s surface. Even if the focal point is just a little too anterior or posterior, the resulting image will be visually distorted. The extent of the distortion will depend on the extent to which the focal point is displaced from the level of the retinal surface. The clinical features of myopia are that of the patient reporting clear vision for near objects, and relatively blurred vision for far objects. On general observation of the patient, it is common to see patients having to squint when trying to focus on details that are far. How does this work?
Well, when one is squinting, one effectively reduces the effective surface area for which light rays are incident on the lens. The effect of this is that only a small amount of focused central light rays are incident on the eye. Pinhole glasses work on this same principle. By shielding our eyes from the unfocused peripheral light rays, less of such unfocused light rays reaches the retina, resulting in better vision. But of course, there is a downside to this. The consequence of squinting or using pinhole glasses is that peripheral vision is hindered (you are effectively preventing unfocused peripheral light rays from reaching the retina after all). The brightness will also be lower (due to having fewer light rays reach the retina). As such, caution should be exercised when using devices such as pinhole glasses. It certainly should not be used when one is driving, due to the dramatic effect it has on one’s peripheral vision. The benefit associated with the mild alleviation of one’s myopia likely doesn’t outweigh the harms associated with the decreased peripheral vision and the decreased brightness.
The poorer the patient’s visual acuity, (visual acuity needs to be assessed independently for each eye), the greater the functional limitation on the patient, resulting in a greater reduction in the quality of life of the patient. It is thus important to address the disease entity – myopia. Survey after survey has found that of all the five senses, people consistently rate sight as the most important. Sight is something that is so easy to take for granted. Just try walking with your eyes closed in your very own humble abode!
The most common way of managing myopia is via prescription lenses. This is not surprising given that it is non-invasive and doesn’t involve the use of topical drugs or invasive refractive surgery which both have their adverse effects and associated risks. As such, the most common first-line treatment of myopia involves one trying a diverging lens with refractive power such that it would diverge the incoming rays of light. This effectively weakens the overall refractive power of the eye and causes the resulting focal point to move posteriorly, back to the retinal surface where it should belong. And of course, a natural question would be – how do we know the strength of the diverging lens to use by determining how much to move the focal point posteriorly by?
For that, we need to go back to the pathophysiology of myopia. The answer is that we can first determine the current focal point for each eye of the patient, and we in turn accomplish that by having the patient undergo a visual acuity test for each eye. That’s how we figure out the corresponding prescription lens to use for each eye. One thing I should just quickly say is that if you (for those of us who have our prescription) look at your prescription, you may see something presented in the same format as this (this is my latest prescription, for those of you who are wondering):
OD: -2.75 -1.75 10
OS: -3.00 -2.25 155
‘OD’ and ‘OS’ are short forms for ‘oculus dextra’ and ‘oculus sinistra’, which are Latin terms for right eye and left eye respectively. As for the numbers in the three columns, ignore the second and third columns for the purposes of this article. Let’s just focus on the first column.
The number in the first column denotes the spherical error. If the number is a negative number, that means the patient needs a lens which weakens the refractive power of the eye (i.e. a diverging prescription lens). You can hence infer from this that the patient is myopic. In this case, the patient’s right eye requires a diverging lens of -2.75 D (D stands for dioptres). Colloquially, at least in Singapore, laymen don’t know and don’t use the term ‘dioptres’. They always talk about ‘degrees’, which is essentially just the magnitude of the spherical error multiplied by a factor of 100. So, if we use the data from the example I have given above, then most people in the local context would say that their right eye is 275 ‘degrees’.
Over the years, as I progressed from Primary Three through Six, secondary school, and even through junior college, I have had to update the lenses on my prescription glasses every two to three years on average. This was because my visual acuity for both eyes deteriorated gradually, albeit at slightly different rates. Normally, when the lenses were changed, I would also take the opportunity to change the frames. However, recently I have decided to maintain the same frames because I truly relish my current pair of glasses.
Allow me to give some background.
I enlisted for full-time national service (a local euphemism for military training lol) in January 2016. In view of that, I decided to update my prescription lenses a month prior to that. So, in December 2015, I went to the optometrists whose services my family has used for the longest of time (Mee Mee Optics, the branch at Bukit Timah Plaza). On that occasion, in addition to updating my prescription lenses, I decided to have these updated prescription lenses in two totally new frames. One frame would have to be a black full-rimmed one in order to comply with the military regulations. For the entire duration of my full-time national service, I would have to don this particular frame. However, I also made another pair of glasses (the MYKITA ‘Rafael’ glasses), which I would wear whenever I was not in camp. In fact, I enjoyed the look of the Rafael so much that I would bring the Rafael to camp, despite having to wear the black full-rimmed glasses most of the time while in the military camp. Nevertheless, whenever I left the camp in civilian attire, I would don the Rafael!
NB: The ‘Rafael’ glasses of the MYKITA No. 1 collection is no longer being manufactured. Its successor is the ‘Dennis’. So I guess you could say that my ‘Rafael’ glasses are limited edition! The images below are taken directly from the MYKITA website, and they show the ‘Dennis’ glasses, which bears an uncanny resemblance to its predecessor (trust me on this one).
For this second pair of glasses, it was specifically a pair of navy blue MYKITA No. 1 ‘Rafael’ glasses which were specially handmade in Berlin. According to the MYKITA website, “Collection NO1 laid the foundation for MYKITA. Fashioned from stainless steel sheets, the frames are made into a three-dimensional structure through a series of bending and folding steps, similar to the Japanese art of origami. The modern principle behind the openly displayed spiral hinge represents the design approach that has informed all subsequent MYKITA collections: the technical solution must also be an aesthetic one.
All the tinted lenses of the NO1 collection come with an antireflective coating on the reverse side and offer total defence from UVA and UVB rays as well as maximum glare protection.”
The ‘Rafael’ model is half-rimmed, and I just think that this lightweight pair of glasses looks incredibly sophisticated. The generally rectangular shape of the lenses complements my face shape a lot. Having a dark colour for the rims and temples of the glasses also complements my dark hair. So, although this purchase was on the relatively pricey end, I was and remain absolutely satisfied by the purchase. Price is what we pay, but value is what we get. I enjoyed it so much that even when I decided to update my prescription lenses in June last year (shortly after I had returned to Singapore for good upon acceptance of the offer to transfer to NUS Medicine), I decided to retain this frame. For now at least, I intend to use these frames indefinitely. I have no intention of changing these frames.
Another relatively piece of good news is that my myopia progression seems to have somewhat stabilised, which is good, considering that my visual acuity could be considered to be at the threshold between mild and moderate myopia. Classifying myopia by severity is clinically significant because it is well known that one’s risk for a retinal detachment is much greater if one’s myopia is severe!
At this juncture, some of you might be wondering what happened to the black full-rimmed glasses. Well, given that I finished my full-time military service obligation for good in November 2017, and that I have not had to go back for military duties, I have not worn those glasses for a long time… Also, unlike my current MYKITA glasses, those black full-rimmed glasses do not have transition lenses, which is something I do appreciate a lot!
In essence, all is well, and I am still wearing the same frame for my glasses even after 6 years! On many occasions, I can’t help but marvel at how technology that has been refined over several millennia has enabled us to develop corrective lenses to treat myopia. I am so grateful that such a treatment option exists. With these corrective prescription lenses, I, along with millions of other people worldwide with varying severity of myopia, have been granted the ability to see normally, and function at our best in contemporary society. Engaging in healthy eye care practices and habits is so underrated.
Take care of your vision (speak to your doctor, optometrist, or ophthalmologist for personalised medical advice), and stay safe even as we get battle the Omicron variant of SARS-CoV-2!
15 January 2022