The role of eye protection in work-related eye injuries.

PURPOSE/BACKGROUND: A recent survey of general hospitals by the Victorian Injury Surveillance System found that ocular trauma represented 15% of work-related injuries. As circumstances surrounding occupational eye injuries have been poorly documented previously, their associations to occupation, industry and work-safety practices, including safety eyewear use, need to be identified to develop appropriate preventive strategies for high-risk groups. DESIGN AND SETTING: From a prospective cross-sectional survey of all eye injuries treated at the Royal Victorian Eye and Ear Hospital, work-related cases were analysed for demographic, occupational and safety eye-wear information. Hospital-based data were supplemented by information from WorkCover Authorities and Labour Force statistics to derive incidence and cost estimates. RESULTS: There were 9390 eye injuries during the 18-month survey period; 42% (n=3923) of total and 29% (n=52) of penetrating ocular injuries occurred at work. The most frequently injured were metal, automotive and building trades workers grinding and drilling (41% of outpatients) and hammering (53% of penetrating eye injuries). Automotive workers had the highest frequency for penetrating injuries, and most were exposed to hammering and were also the least likely to wear safety eye-wear. CONCLUSION: Eye injuries are frequent (10% of work-related injuries) and highly preventable by the correct use of safety eye-wear, a cost-effective intervention that may result in cost savings of $59 million for work-type activities in the occupational and domestic settings in Australia each year.

Eye injuries in Victoria, Australia.

OBJECTIVE: To outline the spectrum of eye injuries in the Victorian population. DESIGN AND SETTING: Prospective survey of all eye injuries treated at the Royal Victorian Eye and Ear Hospital; and a review of morbidity data from all Victorian hospitals to estimate the incidence of ocular trauma across the State. RESULTS: During a 12-month period, 6308 patients were treated at the hospital. Most had superficial injuries, but 401 (6%) were admitted for severe trauma. Most were male and young; children aged under 15 years comprised 25% of hospitalisations (severe injuries). The workplace accounted for 44% of all injuries and 19% of severe trauma, including ruptured globes and internal bleeding. Sports injuries accounted for 5% of all injuries, but 19% of severe injuries. The incidence estimate for penetrating eye injuries was 3.6 per 100,000 population. The incidence of eye injuries requiring hospitalisation was 15.2 per 100,000. Annual medical costs were estimated conservatively at $15.8 million a year for this hospital alone and projected at $39 million a year for 29,000 eye injuries in Victoria and $155 million a year for 116,000 cases nationwide. CONCLUSIONS: Most ocular trauma occurs in young people and could be prevented by proper use of safety eyewear.

Secondary hemorrhage in traumatic hyphema. Predictive factors for selective prophylaxis.

BACKGROUND: Treatment to decrease the rebleeding rate in traumatic hyphema remains controversial. Although antifibrinolytics recently have been shown to reduce secondary hemorrhage rates, their routine use has not been widely applied because of adverse side effects and the relatively low frequency of severe hyphema complications. Alternatively, their use may be restricted to patients at high risk, but prognostic factors for rebleeding have not been clearly identified. METHODS: From a prospective ocular trauma survey, 371 patients with traumatic hyphema were identified, and Fisher's exact test was applied to test for significant differences between patients who did and did not rebleed for various characteristics. Significant factors contributing to rebleeding were fitted into a multiple logistic regression model, and odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. RESULTS: Secondary hemorrhage occurred in 8% of patients and was significantly more frequent in those with visual acuities of 20/200 or less (OR = 3.1; 95% CI = 1.3,7.5), initial hyphema more than one third of the anterior chamber (OR = 2.8; 95% CI = 0.9,8.0), delayed medical attention more than 1 day after injury (OR = 2.9; 95% CI = 1.0,8.4), and elevated intraocular pressure at time of first examination (OR = 2.9; 95% CI = 1.1,7.9). The secondary hemorrhage rate rose from 5% without any of these specified factors to 15% with at least one factor present. No statistical associations were found for age, injury-related iris abnormalities, or aspirin usage. CONCLUSION: Using multivariate logistic regression in populations with low rates of secondary hemorrhage, a predictive model may be used to categorize patients who have higher rebleeding rates, for whom possible benefits may outweigh the risks of prophylactic treatment, and those with lower rebleeding rates, who may not necessarily benefit from treatment.

Sports-related eye injuries.

OBJECTIVE: To: (i) determine the magnitude and describe the spectrum of sports-related eye injuries; (ii) compare the sporting profile variations within Australia and overseas; and (iii) provide recommendations to help decrease the frequency and severity of eye injuries in sports. DESIGN AND SETTING: Descriptive study of sports-related eye injuries identified from a cross-sectional survey of ocular trauma treated in an eye hospital during a two-year period from November 1989 to October 1991. RESULTS: Although sports injuries comprised only 5% of all eye trauma, they accounted for a disproportionately high ocular morbidity, representing 22% of hospital admissions. Most patients were admitted for hyphaema (81%), but there were eight ruptured globes and 20 other cases required surgical repair. For those hospitalised for serious injuries, 19% were legally blind (visual acuity < or = 6/60) and 10% had visual acuity between 6/18 and 6/36 initially, with 29% of patients recording a visual loss in excess of 50% incapacity (< or = 6/18) at three months after injury. CONCLUSION: Eye injuries were most frequently caused by squash, badminton, Australian Rules football and cricket, a sports profile distinctly different from those of the United States and United Kingdom. That none of the players in may study had worn correct eye protection offers a wide scope for preventing injuries in what should be safe recreational pastimes.

Detection of hepatitis B virus DNA in tears by polymerase chain reaction.

OBJECTIVE: To assess the possibility of transmission of hepatitis B virus (HBV) via tears. METHODS: Tear and plasma specimens were collected from 36 carriers of HBV, and the presence of HBV DNA was investigated using the polymerase chain reaction (PCR). RESULTS: Ten (29.4%) of the 34 carriers of chronic HBV and one of the two patients with acute hepatitis B had plasma specimens that were positive for HBV DNA using PCR. Sixteen (47.1%) of the 34 carriers of chronic HBV had tear specimens that were repeatedly positive for HBV DNA using PCR, 10 (29.4%) had tear specimens that were repeatedly negative, and the remaining eight (23.5%) had tear specimens that were equivocal. Both of the patients with acute hepatitis B had tear specimens that were positive for HBV DNA using PCR. CONCLUSION: Hepatitis B virus DNA can be demonstrated in the tears of carriers, even those who were asymptomatic.

Immunopathology of scleritis.

Conjunctival and scleral biopsies from 25 patients with necrotizing scleritis and 5 patients with recurrent nonnecrotizing scleritis were studied by histopathologic, immunofluorescence, and immunoperoxidase techniques. Vasculitis with fibrinoid necrosis and neutrophil invasion of the vessel wall was present in 75% of the scleral and 52% of the conjunctival specimens. Vascular immunodeposits were found in 93% of the scleral and 79% of the conjunctival tissue tested by immunofluorescence techniques. A dramatic increase in the number of inflammatory cells over normal controls was detected in both tissues by immunoperoxidase techniques. In the conjunctival epithelium, there were significantly more T-helpers, macrophages, and B cells. In the conjunctival substantia propria, there were significantly more T cells of all types, macrophages, and B cells. Likewise, scleral specimens showed an increase over controls of T cells of all types and macrophages. HLA-DR expression was dramatically increased in both tissues. Immune-complex-mediated vasculitis plays a pivotal role in the pathogenesis of necrotizing scleritis and recurrent nonnecrotizing scleritis. Induced HLA-DR expression on ocular nonimmune cells and T cell controlled responses also may participate.

Cataract surgery and intraocular lens implantation in patients with uveitis.

The authors reviewed the outcome of extracapsular cataract extraction (ECCE) in 44 eyes of 38 patients with uveitis. Thirty-two of the 44 eyes received a posterior chamber lens implant; 87% of these achieved a stable visual acuity of 20/40 or better. Sixty-seven percent (8 of the 12 eyes) not receiving an implant achieved this level. The authors' results and current literature suggest that absolute control, preoperatively and postoperatively, of all uveitis inflammation and careful selection of patients as lens implant candidates are crucial for successful cataract surgery in uveitis patients. Complete removal of lens cortex and placement of an all-PMMA posterior chamber lens within the capsular bag are also believed to be important.

Microbial keratitis complicating penetrating keratoplasty.

A retrospective review of 68 consecutive episodes of microbial keratitis complicating 66 penetrating keratoplasties (PKs) showed major risk associations: suture-related problems (50%), contact lens wear (26%), previous herpes simplex infection (15%), graft failure (15%), and persistent epithelial defects (15%). Topical steroid (85%) and antibiotic (59%) usage were common iatrogenic factors. Half the infections occurred more than 1 year after grafting. Bacterial infections involving gram-positive organisms (59%) predominated, except for patients with extended-wear hydrophilic contact lenses, which usually involved gram-negative bacilli. The incidence of fungal infections (6%) was relatively low. Recommendations to minimize microbial keratitis include prompt attention to exposed, broken, or loose sutures, and preventive and therapeutic management of epithelial defects. The inadequacy of low-dose antibiotics in precluding microbial infection in many cases and the propensity to develop infections with resistant organisms suggest that guidelines for using postoperative and prophylactic topical antibiotics require reevaluation.

Corneal infection in mucosal scarring disorders and Sjögren's syndrome.

We reviewed 69 episodes of microbial keratitis occurring over an 11-year period in 56 patients with a mucosal scarring disorder or Sjögren's syndrome. Gram-positive bacterial isolates were the most common cause of infection, and accounted for almost all cases in patients with Sjögren's syndrome. Trichiasis (cicatricial pemphigoid), topical corticosteroids, bandage contact lenses, and corneal surgery were the main predisposing factors in the development of the corneal infection. In patients with ocular cicatricial pemphigoid, infection was much less common after chemotherapeutic control had been achieved. Recurrent infections were relatively frequent. There was a high rate of major complications, particularly in microbial keratitis complicating Sjögren's syndrome.

Episodic conjunctival inflammation after Stevens-Johnson syndrome.

The authors studied the histopathologic, ultrastructural, and immunopathologic characteristics of conjunctiva from patients with Stevens-Johnson syndrome (SJS). A small subset of SJS patients with recurrent conjunctival inflammation unassociated with external factors such as lid margin keratinization, sicca syndrome, trichiasis, or entropion was identified. The ultrastructural and immunopathologic characteristics of the conjunctiva from these patients were distinctly different from those of the conjunctiva from SJS patients without recurrent conjunctivitis, and suggested an active, immunologically mediated inflammation. Vasculitis or perivasculitis, immunoreactant deposition in vessel walls, vascular basement membrane disruption, thickening, and reduplication, and a preponderance of helper T-lymphocytes, macrophages, and Langerhans' cells were the notable distinguishing features in those patients with recurrent conjunctival inflammation. This rare clinical syndrome may represent the ocular counterpart to recurrent dermal or oral mucosal erythema multiforme.

Corneo-scleral rim cultures: donor contamination a case of fungal endophthalmitis transmitted by K-Sol stored cornea.

This retrospective study of 549 corneo-scleral rim cultures shows that gentamicin, used in MK and K-Sol medium storage at 4 degrees C, has decreased donor contamination from 43% in whole-globe storage to 13%, but failed to eliminate coagulase negative staphylococci (37%), streptococci (28%) and fungi (28%). Donor-to-host transmitted staphylococcal and streptococcal endophthalmitis have been reported previously. We present the first documented case of donor-to-recipient transmitted fungal endophthalmitis following corneal transplantation using corneas stored in MK or K-Sol solution at 4 degrees C; Candida albicans was isolated. Recommendations are made to assess critically the true incidence of donor fungal contamination and the necessity of adding anti-mycotic agents to preservation medium for 4 degrees C storage. In the absence of ideal antimicrobial cover for corneal preservation solutions, stringent prophylactic measures to reduce contamination and continued monitoring of corneo-scleral rim cultures are warranted, if the poor visual consequences of donor-to-host transmitted endophthalmitis are to be avoided.

Cryopreservation of the rabbit cornea: freezing with dimethyl sulphoxide in air or in medium.

There have been considerable difficulties in developing a satisfactory method for the cryopreservation of corneas. In this paper we describe the effect of two variables that appear to influence the effectiveness of preservation, the concentration of cryoprotectant and the medium that surrounds the cornea during freezing. Rabbit corneas were exposed to the cryoprotectant dimethyl sulphoxide (Me2SO) in concentrations of 1 or 2 mol/l in a high-potassium well-buffered solution, and then cooled to -196 degrees C either in air or surrounded by 5 ml of the Me2SO solution. After storage at -196 degrees C, thawing and removal of the Me2SO, survival was assessed by electron microscopy and measurement of stromal thickness during perfusion on the specular microscope. The least degree of damage was observed when corneas were equilibrated with 1M Me2SO and frozen in air. The evidence suggests that 2M may be an excessive concentration of Me2SO in this system and that damage to the stroma may be reduced by freezing the cornea in air rather than surrounded by the Me2SO solution.

Osmotic properties of the rabbit corneal endothelium and their relevance to cryopreservation.

The process of cryopreservation subjects cells to gross changes in the composition of the solution that surrounds them, changes that cause the cells first to shrink and then to swell by an osmotic mechanism. Empirical methods have been developed that permit many cells to survive freezing and thawing, but the cornea, which is crucially dependent upon the function of its endothelial monolayer, has proved quite refractory. In this paper we explore the osmotic response of the corneal endothelium of the rabbit to solutions ranging in osmolality from 0.25 to 8.6 X isotonic. Boyle van't Hoff behavior was observed between 0.43 and 8.6 X isotonic, and there was an apparent nonosmotic volume of 33.6%. However, ultrastructural damage was observed at the limits of this range, and it appeared that the tolerated range was 0.64-4.4 X isotonic. We show the extent to which dimethyl sulfoxide (Me2SO) would be expected to moderate changes in volume during freezing and suggest that its initial concentration should be at least 2M to prevent excessive shrinkage. We also show that cell swelling during removal of Me2SO is especially likely to be hazardous.

Cryopreservation of rabbit corneas: assessment by microscopy and transplantation.

Rabbit corneas were frozen and thawed by three methods and compared by full thickness transplantation as well as specular microscopy, histology, and transmission electron microscopy. Two of the methods used a recently described technique, in which the excised cornea was immersed in a potassium-rich buffered solution containing the cryoprotectant dimethyl sulphoxide (Me2SO, 2 mol/l). This solution was designed to restrict the loss of intracellular potassium and to prevent cell swelling at low temperatures. In one group the corneas were frozen and thawed surrounded by 5 ml of medium, while in the second group corneas were drained of excess fluid and frozen in air. The third group consisted of corneas cryopreserved by Capella and colleagues' method. All the cryopreserved corneas were damaged, but those that had been frozen in air after exposure to the new medium showed better structure and function than corneas frozen by either of the other two techniques.

Ophthalmic manifestations of pituitary apoplexy.

A case of pituitary apoplexy which occurred in a patient with prolactinoma is reported. The signs and symptoms on presentation were headache, loss of vision, sixth-nerve palsy, subarachnoid haemorrhage and fever. Physicians are alerted to the necessity of prompt and accurate diagnosis in this condition to allow urgent decompression of the anterior visual pathways.

Ocular toxicity of quinine.

A case of ocular toxicity of quinine is described. The effectiveness of a number of treatment modalities is evaluated in the light of its pathogenesis and potential for spontaneous recovery of sight.