Chemical injury, ocular

No international or national databases were found that specifically collect data on ocular chemical injuries. There are individual publications detailing bums in general or chemical biuns (including eye and/or skin bums) in a region or country and case series from bum centers, hospitals, or groups of hospitals. Occupational bum data are usually regional in nature or are case series. National Poison Center databases such as the US American Association of Poison Centers National Poison Data System (NPDS) collect data on the annual number of eye exposures, but do not contain specific information... 

In a 5-year retrospective study of 383 patients with eye injuries (397 eyes involved) in Croatia, 13.6% sustained chemical injuries [7], Of the total patients with burned eyes, 54 required hospital admission [7], A 7-year retrospective study of 60 hospitalized cases of pediatric eye injuries in Hong Kong found that 10% were ocular chemical bums [8],... 

The US Bureau of Labor Statistics collects data annually regarding workplace injuries. The latest data at the time of this writing are from 2006. While these data are quite nonspecific and difficult to relate directly to the epidemiology of ocular chemical injuries, they do provide some insight into the scope of the problem. All of the following data refer to private industry and cases ofnonfatal injuries or illnesses resulting in lost work days. 

In a retrospective study of 148 cases of occupational eye injuries in Germany, ocular bums (not specified as chemical or other etiology) comprised 15.5% of the total [10]. In another German study of 101 patients with 131 severely burned eyes, 72.3% of the injuries were work-related, 84.2% were chemical injuries, and 79.8% of these were due to alkalis [11], Of 42 cases of alkali ocular bums admitted to a German eye clinic between 1985 and 1992, 73.8% involved industrial accidents [19]. In Finland in 1973,11.9% of all industrial accidents were ocular injuries and bums comprised 3.6% of these (chemical or other injury mechanism not specified) [12]. A 7-year retrospective Australian study of 182 industrial bums found that 5.5% were ocular bums due to chemicals, gas explosions, and electric flashes (percentages not specified) [30]. In a 4-year hospital-based study in Taiwan, of 486 patients with eye injuries, 39.9% were work-related [20]. Chemical ocular bums accounted for 19.6% of these injuries [20],... 

Saini and Sharma [30] reported a series of 145 chemical eye injuries in 102 patients treated at a major referral center in India between 1984 and 1991 [30]. Bilateral injuries were seen in 42.1% of patients. Acids and alkalis accounted for 80% of chemical ocular injuries in this series. Two-thirds of the injuries occurred in young people working in laboratories and factories. Roper-Hall Grade III and IV injuries were seen in 52 eyes (35.9%). In total, 102 eyes (70.3%) recovered with a visual acuity of 6/60 or better. Ten eyes (6.9%) had no light perception. Phthis bulbi (a deformed eyeball with no light perception) occurred in 71.4% of the seven deliberate chemical assault victims but in only 3.6% of the accidental ocular chemical exposures. The final visual acuity was better in the eyes with less severe grades of chemical injuries on presentation [30],... 

Table 2.1 Some chemical substances reported to cause ocular chemical injury ...

Ocular chemical injuries are a significant problem. Existing published data on the epidemiology of such injuries are incomplete. Currently recommended decontamination with water or other commonly available solutions such as normal saline cannot always prevent serious eye injuries. Alternative active eye decontamination solutions should continue to be investigated. 

Herr, R.D., White, G.L., Bemhisel, K., Mamalis, N., Swanson, E. Clinical comparison of ocular irrigation fluids following chemical injury. Am J Emerg Med 9, 228-231 (1991)... 

At high concentrations, CN may result in chemical injury to the eye with corneal and conjunctival edema, erosion or ulceration, chemosis, and focal hemorrhages. CN-induced ocular effects on the rabbit eye following exposure to various formulations included lacrimation, chemosis, iritis, blepharitis, and keratitis, with severity dependent on the formulation. 

In the conjunctiva and cornea, sulfur mustard exposure causes loosening of epithelial cells accompanied by corneal edema and opacification (Warthin Weller, 1919). Even low-dose exposure of sulfur mustard to the eyes can be incapacitating (ocular ICt5o = 50 to 100 mg-min/m3). Only limited studies of sulfur mustard-induced eye injuries in animals are available (Kadar et al., 1996 Maumenee Scholz, 1948 Warthin Weller, 1919). These suggest that the microscopic pathology is similar to most chemical injuries with the exception of acid and alkali bums. 

Josset et al. [4] found that there were approximately 7,000 serious chemical splash injuries in France per year, with about half of these cases involving the eyes [4]. Chemical eye splashes made up about 9.9% of ocular trauma in the USA and 7.2% in a UK casualty department however, most were with rather innocuous substances such as hairsprays and shampoos [5]. Acid and base eye bums were 1.6% and 0.6%, respectively, of total eye injuries [5]. 

Ocular bums comprise about 7-18% of ocular trauma presenting to emergency departments in the USA and eye injuries account for about 3 % of total occupational injuries [6]. Most of these (approximately 84%) are chemical bums. About 15-20% of patients with facial bums also have ocular bums. The ratio of acid/alkali chemical ocular bums is 1 1-1 4 [6]. 

Amongst a series of 38 victims of chemical assault (acids) in Bangladesh, 10 (26%) had injuries of the eyeballs and 18 (47%) had injury of the eyelids [26]. Merle et al. [27] smdied 66 patients with alkali ocular bums (104 eyes) in Martinique (French West Indies) over a 4-year period, of which nearly half (45.5%) were due to deliberate chemical assault (the most frequently involved product was AlkalL 15.3% ammonia, pH 12.8) [27]. 

Cartotto et al. [34] reported a series of patients treated at the bum center in Toronto, Ontario, Canada [34], Of the total 24 chemical bum cases, there were 8 chemical eye splashes. Five of these eight patients were decontaminated at the scene (presumably with water). The three chemical eye splash patients who did not receive immediate decontamination developed severe ocular injuries. However, three of the five who had immediate decontamination developed comeal erosions and one patient with eye exposure to black liquor developed a very deep comeal erosion leading to blindness [34]. 

As an introduction to the field of chemical ocular bum lesions, an historical and epidemiological perspective has been reviewed by an historian, an ophthalmologist, and a medical toxicologist. Next, a section is presented covering an expanded review of the mechanisms of action and reactivity of chemicals which can cause ocular injuries, prepared by a group of chemists and physicians. 

Following this are two sections prepared by practicing ophthalmologists which discuss clinical evaluation and current surgical treatment of ocular chemical bum injuries. 

The book concludes with a section prepared by a chemist/physicist who conceived the innovative possibility of an active decontamination solution for ocular chemical splashes and an emergency physician who discuss specific decontamination measures and the emergent care of patients with ocular chemical bum injuries. 

This work will prove useful for medical students, physicians-in-training, occupational medicine physicians and nurses, and private practice or hospital-based ophthalmologists, as well as for occupational health and safety personnel who deal with prevention and first aid measures for ocular chemical splashes, and who wish to supplement or update their understanding of ocular chemical bum injuries. 

The authors goal is to promote the most beneficial care for patients with chemical ocular bum injuries by presenting the most precise and pertinent current information, and thus increasing communication and coordination between the various professionals involved in the prevention and treatment of such patients. 

A number of industrial chemicals were screened using AFNOR protocols with rabbits as the test systems. Information on the appearance and irritancy potential of different chemicals (and the classification thereof) offers valuable clues to the worker to avoid skin injury (Table 16-4). Certain drugs normally used by humans can cause adverse effects on eyes. The types of ocular disturbance are blurring of vision and diplopia, impairment of visual acuity, yellow vision (xanthopsia), corneal opacities, and lenticular opacities and drugs producing or precipitating the formation of cataract, which have been implicated with the use of candidate drugs. 

---