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Editor,—Flitcroft’s recent commentary1 asserts “myopia clearly represents the failure of the normal emmetropisation mechanisms” but that “myopia may represent a physiological adaptation to prolonged near work with the mechanisms of the emmetropisation regulating eye growth to a state that minimises retinal image blur for near”. These two apparently contradictory views beg the question as to what is normality in the context of refractive status.
Ophthalmology has embraced the current trend in medicine towards using quality of life measures as outcome indicators. Indeed, such measures have been used to evaluate outcomes of laser correction of myopia.2 3 It is said that to become myopic has a potentially negative impact on self esteem, career choice, and ocular health.4
However, we have been unable to identify baseline studies which indicate whether myopes themselves feel they have a significantly impaired quality of life, and if so, at what degree of myopia problems can be expected. Before committing further resources in efforts to treat myopia, it should surely be more clearly demonstrated that there is a patient driven demand for such intervention.
Without this evidence, it could be argued that we fail to recognise that the increase in the prevalence of myopia5is nothing more than the adaptation of an increasingly literate, predominantly urbanised populus who may use near vision for a large proportion of their waking hours. Furthermore, treatments which “cure” myopia may deprive middle aged moderate myopes of the ability to perform near work without optical correction. Increased longevity means that for many people their life expectancy is such that the majority of their years will be in a presbyopic state.
While we recognise that innovative refractive procedures are a natural development of microsurgical techniques and they are likely to gain a justified place in the treatment of high degrees of refractive error, we feel that there is need for more information about those myopes (about 20% of the population) who are as yet not putting themselves forward for anything other than conventional optical management.
Reply
Editor,—Rose and Tullo suggest that we need more evidence that there is a real demand from myopes for methods of treatment before committing resources to research in this field. Certainly no ophthalmologist should be encouraging contented myopes to undergo any form of intervention be it surgical, pharmacological, or behavioural. Equally, the contentedly myopic should not assume that other myopes share their contentment. The number of people who willingly undergo refractive procedures and express high levels of satisfaction afterwards is surely an indication of demand.
Rose and Tullo also raise the issue that with increased longevity treatment of myopia will merely compound the inconvenience of presbyopia. Although presbyopia may be inconvenient to the emmetropic, myopia is also linked with other degenerative conditions affecting the peripheral retina and macula that carry the risk of significant visual deficits. Understanding the physiological basis of the abnormal patterns of ocular growth that lead to myopia may allow us to prevent some of these associated conditions and the associated visual morbidity. Clearly such benefits will not arise from developments in refractive surgery but from a better understanding of the aetiology of myopia that will allow preventive strategies to be developed.
Management of the complications of myopia unquestionably falls within the current remit of ophthalmologists. The increased levels of myopia most notably seen in the Far East represent an increase in both the incidence and degree of myopia. While research on the demand among myopes for treatment strategies would be welcome, much more pressing are data relating to the implications of an increasingly long lived and myopic population for ocular morbidity. This will allow ophthalmologists to anticipate the increased demands on their services that will be the likely consequence of increased levels of myopia.
In the final analysis, arguing that myopia is an acceptable consequence of an increasingly literate urbanised population appears to me to be the equivalent of regarding a disabling condition of the legs as an acceptable consequence of an increasingly sedentary society.