Ophthalmology is the medical specialty concerned with the eyes, their surrounding structures, and the visual apparatus in the brain. Although the specialty is often in the public eye due to media attention, it is glossed over in most undergraduate curricula, with the average medical student spending only 2 weeks on it in five years of training.
This can make it very difficult for legal professionals involved in a personal injury case to obtain useful reports from medical practitioners in ophthalmology cases.
Qualifications
The postgraduate exams in ophthalmology are either the FRCS (Fellowship of the Royal College of Surgeons) or the FRCOphth (Fellowship of the Royal College of Ophthalmologists). Entry in the specialist register of the General Medical Council (GMC) is required to become an NHS consultant in the UK.
Personal injury
The eyes are commonly involved in trauma. Injuries commonly occur at work, in assaults, or in motor vehicle accidents.
Causation
Sometimes this is straightforward, as encountered in cases of visual loss in direct eye injury, with documentary evidence of good vision before the incident. Often, however, causation must be assessed on a balance of probabilities. A good example of this is a recent case where, following at rear end vehicle shunt, a client was found to have a retinal vein occlusion. In this condition, a clot occurs in a vein draining blood from the eye, and visual loss occurs in the territory of the blocked vein. A literature search confirmed one case of impact causing this condition. The condition is much more commonly seen, however, in patients with high blood pressure. As the client had high blood pressure and, as reported cases of impact causing vein occlusion are so rare in the literature, it was felt that the chance of the impact causing the condition in his case was less than 1%; the case failed on causation.
Personal Injury at Work
The Management of Health and Safety at Work Regulations 1992 require employers to perform a risk assessment of the workplace.
Risk assessment should include the possibility of chemical splashes to the eyes, the number of employees likely to be affected, and the optimum sites for positioning of emergency eye wash stations. Training should be given to staff in the actions to be taken if they or their colleagues are injured. Training must be updated regularly. Immediate irrigation is the priority in chemical injuries, and can save sight.
In personal injury cases, it is important to determine whether risk assessment has been carried out, whether eye protection has been supplied by an employer, and whether it has been worn by the employee. It is also important to determine whether an employer has trained suitable first aiders, and provided first aid "eye wash" stations.
Workplace hazards and their effects are summarised in the Table. These include particles, chemicals, allergens, display screen equipment (DSE), lighting, lasers and trauma.
Fibres and dust (particles) in the atmosphere cause watering of the eyes (lacrimation), which can reduce visual acuity and be distracting. This may compromise safety in mining and working at height.
With chemical hazards, the mechanism of the injury depends on the chemical agent. While injury may be caused by splashing, the eye is also affected by the same gases which cause respiratory problems, such as ammonia. Acids commonly cause superficial effects, do not always penetrate the eye, and may be associated with a good visual prognosis. Alkali, in contrast, penetrates the eye, causing deeper internal burns and a poor outlook for vision.
In protecting workers from allergens, adequate ventilation may be more effective than eye protectors. ASHRAE (the American Society of Heating, Refrigeration and Air Conditioning Engineers) recommends environmental controls for animal rooms at 10-15 air changes per hour with 100% outdoor air, a relative humidity of 30-60%, and a temperature 61-84 degrees F. Good workplace hygiene reduces exposure to hair, dander, urine and saliva. Lab coats, gloves, face shields and respirators may be required, and emergency procedures should be in place for managing severe allergic reactions (anaphylaxis), including staff training in CPR and availability of epinephrine.
In animal handlers (vets, vet nurses, breeders, trainers, laboratory animal handlers and scientists) who develop allergic symptoms, 80% will report symptoms in the eyes and nose (rhino-conjunctivitis), 40% will have skin symptoms (dermatitis) and 30% will have a form of occupational asthma. In one study of attendees at an international conference, veterinary nurses were found to have a prevalence of allergic disorders of 39%.
With display screen equipment (DSE), temporary effects occur due to the inherent blur of the image. Blur is a stimulus to the accommodation reflex, and the eyes therefore undergo a constant focussing search, which is tiring and inaccurate. Concentrating on DSE also results in a reduction in blink rate, which can produce dry eye symptoms. Frequent work breaks are advised to avoid these temporary effects, particularly with visually demanding or repetitive work, and this is written into the Health and Safety (Display Screen) Regulations 1992.
Headaches attributed to eyestrain may in fact be due to ergonomic problems, such as poor posture and muscular strain. The Display Screen Regulations emphasise the importance of correct seating at workstations, with flexibility in the positioning of the screen, keyboard and source material, allowing the operator to adjust the workstation to meet their own visual requirements. Equipment should be properly maintained to avoid flicker, glare and reflection.
Normal reading spectacles are set for a working distance of 33cm and may not correct sight at the distance of DSE work (typically 75-100 cm). The EC Directive entitles "users" (people who use a screen several hours a day) to be tested periodically and makes the employer responsible for the provision of an optical correction necessary for the DSE task at the appropriate working distance. In terms of lighting, the MHSW Regulations 1992 require employers to have lighting which is suitable and adequate to meet the requirements of the workplace. An assessment must include whether lighting arrangements are satisfactory, whether they pose any significant risk to staff, and whether emergency lighting is required. Diffuse lighting is augmented by local lighting at each workstation, under the control of each employee; it is important to avoid this becoming a source of glare for other employees working in the vicinity.
"Laser" is an acronym for light amplification by stimulated emission of radiation. Laser light is monochromatic (single wavelength), collimated (parallel), coherent (in-phase), and delivers high energy over a small area. Lasers are classified according to their energy level and risk of injury. Their thermal effects are retinal burns, which can cause permanent holes in the field of vision (scotomas). A burn has a more damaging effect if it is at the fovea, which occurs when the victim is looking directly at the laser source at the moment of discharge.
In addition to these acute laser eye injuries, there is a more chronic form of damage due to cumulative exposure. This causes diminished colour vision in workers using lasers over long periods, particularly with inadequate eye protection. Multiple types of eye-protecting filters exist to protect against laser-beam related eye injuries, and it is imperative that the eye protection worn by the worker contains a filter appropriate to the wavelength of the laser being used. Non-beam hazards of lasers include thermal injury, fire, smoke plume and electrical hazards.
Alleged laser injuries can result in legal claims, and evidence-based protocols for diagnosis and management of laser injuries should be ready in the workplace. Laser lesions causing serious visual problems are apparent on eye examination, and do not cause chronic pain without physical signs of injury.
In one study of all eye injuries over a one year period in Glasgow, it was found that 60% were due to work. The majority of work-related eye injuries were due to buffing and grinding, and in 83% of injuries the required eye protection was not being worn. In the Hong Kong construction industry, 85% of eye injuries occur when no eye protection has been worn. Eye protection must be part of a program of continuous staff training, within a culture of safety-consciousness. Standards exist for different forms of protection (for example, BS EN 166 for personal eye protection, BS EN 169 for personal eye protection used in welding). One supplier (Bunzl) offers over 200 different products for eye protection! These are selected based on the type of hazard, the type of protector (for example spectacle or facemask) and the type of lens.
This can take the form of blunt eye injury or of penetrating injury, particularly when glass has fragmented. Injuries encountered in the workplace include orbital fractures, lacerations and intra-ocular foreign body (IOFB). Contusion injuries of the eye may cause late traumatic cataract and glaucoma. Compressed air injuries are occasionally seen. Eye protection for agricultural workers should not be neglected. In fungal keratitis, implantation of spores into a corneal abrasion by vegetation or an animal matter causes sight-threatening infection.
Personal Injury in Assaults
The visual system is commonly involved in head injury cases. This ranges from serious penetrating head injury to focal brain injury with selective damage to language-processing centres. The client may develop problems with the visual field or with the movement of the eyes.
There may be associated facial fractures and lacerations. Facial fractures involving the nasal bones commonly cause watering of the eye due to damage to the naso-lacrimal ducts.
Blunt or penetrating eye injury can have late consequences, such as the development or acceleration of cataract and glaucoma. The vitreous jelly inside the eye may detach, causing floaters, or the retina may detach, necessitating multiple operations which may only partially correct the vision.
There have been instances of laser pointers being used in assaults by "laser louts" at sporting events and even in attempts to blind the pilots of landing aircraft.
Personal Injury in Motor Vehicle Accidents
Motor vehicle accidents can result in direct eye injury, and can also be associated with secondary injuries due to airbags and seatbelts. Airbags cause compression injuries of the cornea, and seatbelts compressing the chest can cause raised blood pressure within the eye with damage to the retinal circulation.
The author has one patient, a young child, who developed injury to one of the nerves controlling the movement of the eyes; when the nerve subsequently re-grew, it grew back onto the wrong muscles, producing bizarre eye movements which not only caused double vision but a severe cosmetic defect which was not amenable to surgery. This affects not only the education of the child but her future employability.
Post-traumatic migraine is well-recognized in the medical literature, and can take the form of new headaches or an exacerbation of pre-existing migraine. Migraine may also occur in the eye without headaches, and the author recently saw a client who had ocular migraine precipitated by over-breathing (hyperventilation) caused by panic attacks, which were in turn a feature of post-traumatic stress disorder due to a motor vehicle accident.
Blepharospasm has also been recognized, and was a prominent feature in two the author's most recent cases, one in a UK vehicle shunt, and one in a head injury due to a trip down the stairs of a Miami hotel. The latter case required several eye operations, and comprehensive medical reporting, culminating in videoconferencing facilities being used to give evidence to a jury trial in Florida; the case eventually settled in excess of US $1 million.
Particularly common in whiplash injuries is an acquired defect of the convergence of the eyes. The system for bringing the eyes together for close vision (as in reading) is damaged due to movement of the midbrain at the point of impact. If this is not directly measured, the client may be labeled as malingering. It is now quite clear in the medical literature that such problems are truly organic and do not always settle after compensation claims have been paid.
Conclusion
Ophthalmology is an interesting and complex medical specialty concerned with the eyes, their surrounding structures, and the visual apparatus in the brain. Medical students typically spend only 2 weeks on ophthalmology in their undergraduate curriculum.
Ophthalmology commonly gives rise to cases in personal injury claims at work, in assaults and in motor vehicle accidents. There are a variety of workplace hazards to the eyes. Employers should carry out a risk assessment and supply protection appropriate to the hazard, and employees should wear it.
A variety of injuries occur in assaults and in motor vehicle accidents including eye injury, head injury, post-traumatic migraine and accommodation-convergence defects due to whiplash.
Legal professionals may find it difficult to obtain useful reports from GP's in ophthalmology cases, and should make sure that they instruct an expert with a minimum of FRCOphth or FRCS, and an entry in the GMC's specialist register.
In the era of evidence-based medicine and judicial scrutiny of expert testimony, it is important that reports contain the results of a literature search and comment on the spectrum of opinion which exists on the topic.
