The specialists at Miranza recommend an annual check-up for people with myopia, including taking intraocular pressure, examining the retina and optic nerve, measuring corneal thickness and visual field. This check-up is key to preventing glaucoma.
Certain aspects of glaucoma are more or less well known, such as its silent progression, the loss of peripheral visual field it entails or the fact that high intraocular pressure is the main risk factor and the only one that can currently be fought against.
However, the close relationship of this disease with some systemic diseases, such as diabetes or hypertension, or eye disorders, such as myopia, is less well known. In this regard, Dr Aitor Fernández, a glaucoma specialist at our Miranza IOA clinic, reminds us that all of these are important risk factors and that the same attention must be paid to all of them in order to prevent vision loss due to glaucoma, which, at first, goes unnoticed: “People with myopia should be aware that they are part of a significant risk group, just like the elderly and those with a family history or with high IOP”, he concludes.
Attention to glaucoma with myopia, especially if you have more than 6 dioptres
When asked whether any myopia carries this associated risk, Dr Elena Arrondo, a specialist at IMO Grupo Miranza, explains that “although the risk affects any myopic person, it increases as the degree of myopia rises and can affect 12% of myopic people with 6 or more dioptres and reach 80% in the case of very high myopia, according to some studies and what we actually see during our examinations on a daily basis”, explains the specialist.
Thus, our ophthalmologists call for people with myopia, especially above 6 dioptres, to undergo regular check-ups that include all the necessary tests to diagnose or rule out the existence of glaucoma.
Dra. M. Jesús Chaves at Vissum Grupo Miranza, specifies that “myopic patients should have their intraocular pressure, fundus (retina and optic nerve), pachymetry (corneal thickness) and campimetry (visual field) checked regularly.” According to the specialist, “the follow-up of these patients is often focused on retinal lesions that are typical of high myopia, and it is easy for people to forget about glaucoma prevention. In fact, it is our fellow retina specialists who often refer these at-risk patients to us for monitoring and follow-up.”
The doctor places special emphasis on highly myopic people who have undergone refractive surgery, since “although they no longer need glasses, their eye is still anatomically myopic; thus, they should also have check-ups and undergo tests for glaucoma.” The ophthalmologist notes that it is in these patients “that we often detect the most advanced cases of glaucoma, because they have stopped their check-ups after undergoing surgery.”
Difficult diagnosis of glaucoma in myopic patients
Moreover, if early diagnosis of glaucoma is difficult in itself, since the disease does not have any obvious symptoms for the patient at an early stage, its diagnosis is complicated when myopia is involved.
According to Dr Arrondo, “in these patients, the pressure may be normal and, whereas their optic nerve is difficult to assess, due to the often high pathology of the eye fundus, which adds more difficulty to the diagnosis.”
The ophthalmologist explains that the visual field of these patients “may have alterations due to myopia that can also mislead us, while the retina may suffer alterations that are apparently the cause of the patient’s visual loss, even if they are not the cause of the loss of vision, which often delays the diagnosis.”
Furthermore, imaging tests, such as Optical Coherence Tomography or OCT of the optic nerve, are also a confusing factor, because these tests are not designed for myopic eyes, as they are based on the comparison of the optic nerve with “standard” patterns, which do not correspond to those of the optic nerve of a myopic patient. For all the above, according to Dr Chaves, “glaucoma associated with high myopia is one of the most underdiagnosed diseases in ophthalmology.”
The challenge: improving the diagnosis and control of glaucoma
However, technological advances suggest that this trend could change. According to Dr Aitor Fernández, thanks to the possibilities offered by artificial intelligence, deep learning and big data, “all the information we have gathered or are gathering now about the eyes of these patients – campimetry, optical coherence tomography, retinographies, etc. – will not have been in vain in a few years, when a great ophthalmological algorithm will be able to discern patterns, observe differences and make classifications, where we are not able to do so now, due to the large amount of data that the human brain is incapable of handling.”
“Soon, with just a photograph of the optic nerve, the ophthalmologist will have a higher probability of providing a correct diagnosis than at present and with an intrapersonal bias of 0, given that patient-oriented technology will support us in the screening process and will allow us to increase the rate of diagnosed patients, with this data having an impact on improving people’s visual health from the onset”, he concludes.
Be it as it may, it is important that patients with myopia take this risk factor into account and undergo regular check-ups. “They are patients who also evolve much faster and with more central defects than other patients and who are controlled at very low intraocular pressures, which is often difficult to achieve, even with surgery”, warns Dr Arrondo.
Therefore, early diagnosis and treatment of these patients in time and exhaustive monitoring of their evolution can be key, due to the diagnostic difficulty and the progression of myopia, which often causes them to continue losing vision at normal pressure levels, which does not occur in other glaucoma patients.
Some basic aspects about glaucoma
- Glaucoma is a progressive neurodegenerative disease that affects the optic nerve.
- The prevalence in Spain is estimated to be around 2%, although only half of the cases are diagnosed.
- The importance of early diagnosis lies in the fact that, once the damage is established, it is irreversible and our efforts as ophthalmologists are focused on preventing the damage from progressing.
- Treatments, which are all aimed at lowering intraocular pressure, the main risk factor for glaucoma, are increasingly varied and effective in slowing down vision loss.
- It is possible to live with glaucoma, even if you have lost vision. Central vision is usually not affected if action is taken in time and the patient commits to chronic treatment and follow-up.