Epidemiology

Scope Of The Problem

Eye injury is a significant disabling American health problem. The National Research Council reported that "Injury is probably the most under-recognized major health problem facing the nation today. The study of injury presents unparalleled opportunities for reducing morbidity and for realizing significant savings in both financial and human terms." The American Medical Association's Guides to the Evaluation of Permanent Impairment rate permanent impairment to the visual system on an almost equal rate of impairment as to the "whole man" ( "a total loss of vision in one eye equals a 25% Impairment of Visual System and a 24% Impairment of Whole Man"

Data from the National Center for Health Statistics' Health Interview Survey, conducted in 1977, estimated that nearly 2.4 million eye injuries occur in the United States annually. This report calculated that nearly one million Americans have permanent significant visual impairment due to injury, with more than 75% of these individuals being monocularly blind. Eye injury is a leading cause of monocular blindness in the United States, and is second only to cataract as the most common cause of visual impairment. USEIR estimates that 500,000 years of lost eyesight occur annually in the United States. Injury is the leading cause for eye-related hospital admissions.

While no segment of society escapes the risk of eye injury, the victims primarily at risk are the young. The majority of all eye injuries occur in persons under thirty years of age. Trauma is considered the most common cause of enucleation in children over three years of age. The toll of injury in such significant proportions, in terms of human suffering, as well as long-term disabilities, loss of productivity, and economic impact, can at present only be imagined.

Current information regarding the public cost of eye injuries is limited to specific types of injuries and specific geographic regions. These figures, if extrapolated to the known frequency of eye injuries in America, offer a perspective on the enormity of the total cost. The National Safety Council estimates that job-related (approximately one-third of all eye injuries) eye trauma costs amount to $300 million annually. This figure includes medical and hospital bills, workmen's compensation, and lost production time. A six-month, hospital-based study conducted in a single urban emergency department in 1985 conservatively estimated costs at $5 million annually. Less than three cents of every dollar spent on eye research supports investigations primarily related to ocular trauma, despite the hundreds of millions of dollars in costs associated with eye injury. In 1988, the Committee to Review the Status and Progress of the Injury Control Program at the Centers for Disease Control recognized that "injury research should be considered an investment that will more than pay for itself by reducing the economic burden of injury and disability." Both eye trauma victims and society bear a large, potentially preventable burden.

The National Society to Prevent Blindness (now Prevent Blindness America) estimates that 90% of all eye injuries are preventable. Through public education campaigns and use of appropriate safety equipment, where available, significant impact upon the incidence of some injuries can be achieved. Impressive reductions in eye trauma incidence of ice hockey injuries through the mandatory use face guards in youth league play, through the cooperative efforts of American and Canadian ophthalmologists, is an example of such a success story. Data collection leads to the identification of particularly prominent preventable causes of eye trauma, to help target specific causes. Continued progress in addressing the public health aspect of eye injury also depends on the adequate collection of data concerning incidence, prevalence, demographics, and causative factors.

Dramatic improvements in the surgical management of ocular trauma have evolved over the past two decades. However, persistent inadequacy in the standardized documentation of eye injury morbidity and treatment outcome limits the development and widespread introduction of techniques for preventing and improving the prognosis of serious eye trauma. Again, the USEIR project has an important role to play as a widespread common platform to describe injuries and outcomes to retrospectively determine which treatments may be best for particular injuries. This information may then serve as a foundation upon which to build a prospective clinical trial to improve medical and surgical care.

Only eight eye injury surveys were published in the United States from 1986 to 1990. Of these surveys, the Eye Injury Registry of Alabama published the sole prospective study including both initial and six-month follow-up visual function. The majority of published surveys are retrospective and hospital-based. Acknowledged limitations of hospital-based studies include "the inability to code more than four secondary diagnoses, the inability to account for multiple admissions for the same injury, errors in diagnostic coding, and limited information on the circumstances under which the injury occurred." Any interpretation of data collected from hospital-based studies must also take into consideration the fact that the criteria for hospital admission may skew the statistics to specific types of severe injuries, omitting a wide range of serious injuries, including nonpenetrating contusion injuries and injuries with late-developing complications. Therefore, the USEIR database complements single-center reports, helps place such reports in the perspective of nationwide prevalence, and also serves as a more broad-based source of information. Participation of individual treating ophthalmologists is critical to the development of comprehensive epidemiologic eye injury data. Documentation of each serious eye injury is important work, and, through this cooperative effort, will ultimately benefit all patients and physicians.