Commentary: Demystifying the need of stringent visual standards for military duties

Military service demands the epitome of fitness from the soldiers and recruits. They have to perform in a very stringent and much different and wide spectrum of work environment spanning land, air, and maritime, compared to the nonmilitary duties in civil setup, that too, under very hostile environmental, occupational, and health conditions.[1] Troops have to remain fit to discharge their duties all the time in widely varying climatic conditions including extreme cold, high altitude, desert, or heavy rains. In the same way, working on ships, on board in a fighter plane, submarine, armored and artillery columns or space warfare, radar, and navigation duties demand excellent visual functions. Since visual functions are one of the most important aspects of medical fitness, visual standards have to be designed as per the need of different trades and professional arms and branches of all the three services of armed forces. These criteria also include adequate vision within the set standards. Various studies pertaining to military populations have been conducted in different countries.[1-4] However, studies on visual standards causing dismissal from military recruitments are limited. Optimum visual standards are the need of the hour as today’s technologically advanced battlefield may cost a soldier’s life if the standards are not met.[5-7]

Previous studies in the literature have found refractive errors, strabismus, and amblyopia to be the most common causes for military rejections.[5-7] This study found a slightly higher rate of trauma-related diseases as the most common cause of monocular legal blindness preventing military service, probably due to regional bias.

The permissible limit of Myopia upto 14.0 D in both eyes laid down by the Turkish Military as the selection criterion and discussed in this study for non selection of the candidates is of utmost importance as this high myopia entity makes the individual highly vulnerable to the trauma sustained during combat military training. However, most of the armed forces, including Indian armed forces, have laid down limits of myopia ranging from less than 0.50 D for flying branches to 5.50 D for legal and medical and allied professions. Refractive errors corrected with refractive laser procedures are included in suitable standards for entry into the armed forces world over.[8] To minimize the probabilities of any undue occurrence of sight-threatening ocular engagement like retinal detachment during the period of training or while performing military duties later on, certain restrictions and well-defined riders have been imposed on the criteria to accept post-refractive laser candidates in the military services. They include the criterion that the permissible age should be more than 20 years at the time of laser procedure. The axial length of the eye ball should not be less than 21 mm and more than 25.50–26 mm, respectively, in different services in the armed forces. The post-refractive laser limits of astigmatism of less than 2 D and a corneal thickness of less than 450 mm have also been laid down on the basis of scientific evidence to corroborate with the definition of pathological myopia, with the intention to rule out any possibilities of sight-threatening complications like retinal detachment during vigorous physical training and subsequent duties. Eyes with a previous history of surgery, trauma, significant retinal inflammations, congenital anomalies, or hereditary disorders like retinitis pigmentosa are invariably associated with poor visual status and compromised binocular visual potential during adverse working conditions. Such pathologies invariably lead to poor vision in adverse working conditions and endanger the life of the soldiers, particularly when combatants are deployed under conditions of compromised light and contrast sensitivities. Hence, recruits suffering from the above-mentioned elements are considered unsuitable for induction into the military services. Because of dissimilarity in national regulation policies in different countries, discrete methodology for ocular assessment may be used. This might bias the ocular findings.[2,5] Overall, the study has nicely attempted to categorize the etiology of different ocular conditions leading to rejection of candidates from military recruitment.