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CASE REPORT
Photoretinitis: an
underestimated occupational
injury?
N. Magnavita
Institute of Occupational Medicine, Catholic University School of Medicine, Largo Gemelli 8,
00168 Roma, Italy
Non-ionizing radiation, which is produced in large amounts by welding arcs, may
induce photophthalmia, keratoconjunctivitis and cataracts. Retinal injuries resulting
from exposure to electric welding arcs have been reported, but such injuries are
not commonly seen and may be misdiagnosed. A case is described of bilateral
maculopathy in a millwright exposed to metal arc inert gas-shielded welding and
oxygen lance light. Insurance adjudicators denied his claim, as they did not
acknowledge the cause-and-effect relationship between welding and retinopathy.
Welding emits a wide spectrum of radiation, ranging from IR to UV and beyond. UV
and far-IR radiation are adsorbed by the cornea and the lens, whereas visible light
and near-IR radiation penetrate to the retina. According to the intensity and time of
exposure, they may cause thermal or photochemical retinal damage, which may
be permanent and sight-threatening. Workers covered by compulsory collective
insurance should be eligible for compensation in every case of welding light-induced
retinal damage.
Key words: IR light; occupational exposure; retinal injury; visible light; welding.
Received 18 September 2001; revised 26 March 2002; accepted 30 April 2002
Introduction
Traditionally, the ocular hazards of arc welding have been
primarily considered to be photophthalmia (welder’s
flash), keratoconjunctivitis and cataracts caused by UV
radiation, which is produced in large amounts by welding
arcs [1].
Retinal injuries resulting from exposure to electric
welding arcs have been reported [1–7], but such injuries
are not commonly seen. Here we report a case of welding
arc maculopathy which failed to attain compensation
from the Italian National Insurance Institute (INAIL),
owing to supposed lack of a causative relationship.
Subject
The patient was a 45-year-old male who had been
Correspondence to: N. Magnavita, Istituto di Medicina del Lavoro,
Università Cattolica del Sacro Cuore, Largo Gemelli 8, 00168 Roma,
Italy. Tel: +39 347 3300367; fax: +39 06 3054481; e-mail: nmagnavita@
rm.unicatt.it
working for >25 years in industrial building framing,
using electric arc welders, metal arc inert gas-shielded
(MIG) and submerged arc welders, and oxygen lances.
He was a skilled welder and had frequently suffered
ocular pain from keratoconjunctivitis, or foreign bodies
penetrating the eye. He never reported sick for such
common eye problems.
In September 1996, he complained of acute ocular pain
while working at a welding arc. In the days that followed,
when in the dark, he became aware of a persistent bright
spot near the centre of his vision. He could not go on
working, because he was unable to see the welding spots.
He went to his general practitioner and was referred on to
an ophthalmic hospital, still complaining of a positive
scotoma affecting the lower part of his central field in
both eyes, blurred vision (‘a tightly woven net, like a
cobweb’) and photophobia.
Ophthalmoscopic examination of the fundus revealed
a circular bright-yellow foveal oedematous lesion in
both eyes. The changes were most evident in the left eye.
Computer-aided field examination showed scotoma in
Occup. Med. Vol. 52 No. 4, pp. 223–225, 2002
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Occup. Med. Vol. 52, 2002
the nasal region of the left eye and remarkable sensitivity
reduction in the corresponding area of the right eye.
Anterior eye segments were normal. Visual evoked
potentials (VEPs) were normal.
The patient claimed worker compensation; INAIL
declared that the worker was entitled to income lost
through acute injury, but rejected the claim of permanent
disability, asserting that there was no cause-and-effect
relationship between the employment and the retinal
lesion. Owing to visual impairment, the worker’s occupational performance significantly worsened and he was
subsequently discharged from his job.
Four years later, in February 2000, the patient came
to our occupational health outpatient department, and
underwent examination and further investigations at the
university clinic. At the time, instead of the pain, a slight
gritty feeling was present and visual acuity was reduced
in both eyes. Pigmented foveal changes in locations
corresponding to the retinal lesions and lack of foveal
reflex were seen in the right eye, while chorioretinic paramacular atrophy was shown in the left eye. On automated
static perimetry, visual field analysis showed enlargement
of the blind spot in the left (22 absolute defects) and right
eye (13 defects). VEPs were confirmed to be normal.
Discussion
Welding emits a wide spectrum of radiation, from IR
to UV light and beyond. UV and far-IR radiation are
adsorbed by the cornea and the lens, whereas visible light
(VL) and near-IR radiation penetrate to the retina [1,4].
The cornea is sensitive to the effects of UV light and
can suffer both acute and chronic toxicity.
UV keratoconjunctivitis, or ‘arc-eye’, is a painful
condition which is not considered a threat to sight in the
long term [1]. It is associated with relatively short exposures to light sources, such as welding arcs or tanning
lamps. The corneal effects are seen within a few hours
following exposure and typically will resolve within 72 h.
Chronic exposure to environmental UV light may lead
to a variety of ocular surface abnormalities that rarely
resolve in the absence of therapy [8–10]. Welding-arc-like
injury may lead to secondary subretinal neovascularization [8]. There is a high prevalence and incidence of
long-term changes in the outer part of the eye in welders
[9,10].
Radiation in the visible and near-IR spectrum
(400–1400 nm) penetrates the eye to be adsorbed by the
retina and may cause thermal or photochemical damage,
which may be permanent and sight-threatening, according to the intensity and duration of the exposure [4].
Retinal lesions induced by arc welding have been called
‘phototoxic maculopathy’ [3], ‘retinitis photoelectrica’
[4], ‘photic maculopathy’ [2] and ‘macular photoinjury’
[7]; all these definitions refer to identical pathology.
Early diagnosis may be difficult, because maculopathy
can be masked in the first few days by a phototoxic
keratitis [7]. In most cases, retinal injuries heal spontaneously without loss of vision [1,4,6]. Severe burns of
the macula, on the other hand, may lead to permanent
complete or partial loss of central vision [1,4,7].
The prevalence and seriousness of the illness depend
both on the intensity and characteristics of emitted
radiation, and the availability of protective measures.
Degenerative changes in the eye macula are very frequent
among East European welders [11]. On the other hand, in
Western countries, retinal lesions are infrequent and less
well known by occupational health specialists. Occupational cases are scattered in the literature: two cases have
been reported by Brittain [1] and three cases by Fich et al.
[4].
A study of routine eye examinations of a general
population showed that 0.14% of people who went to a
primary eye care provider had photic maculopathy [12];
15% of these were caused by looking at welding light
without eye protection and the remaining by sungazing,
substance abuse and psychiatric conditions [12].
MIG welding poses a greater threat to sight than other
types of welding, because light emission is brighter and
richer in VL and near-IR radiation than in a conventional
rod arc [1]. Oxygen lances are even brighter than MIG
welders. Protective lenses give no absolute protection
[13]. In fact, radiation may be reflected into conventional
welding helmets, thus causing undue exposure, even if
work is performed at the welding desk [14]. There is
anecdotal evidence that, in building yards, workers often
have to lie on the floor or stretch in unnatural positions
that do not allow the use of personal protective devices.
They therefore cannot avoid looking momentarily at the
intense light emitted from welders without any protection, especially when background light is insufficient.
Moreover, in crowded workplaces, a worker may be
exposed to the light emitted from another adjacent
welder.
Our patient sustained macular burns from MIG and/or
oxygen lance welding. The seriousness of the lesion was
not promptly recognized. The worker compensation
system allocated benefits for days off work, but denied
permanent disability, assuming that there was no causeand-effect relationship. The patient was recognized as
disabled on the basis of a court’s verdict only in 2001, i.e.
5 years after the accident—when he had already lost his
job.
Causation is frequently a critical issue in worker compensation and liability cases. The question usually arises
as to whether the condition was pre-existing or whether it
was caused by an accident or occurrence that is not a
subject of the claim in question. With an acute injury this
determination should be simple.
Before the injury, the worker had normal vision. He
N. Magnavita: Photoretinitis
had no other illnesses affecting the retina or other parts
of the eye. This means that there was a high probability
that retinal impairment arose as a result of the work
in question. The available information suggests, with a
reasonable degree of medical certainty, that exposure
to MIG and/or oxygen lance welding caused the
maculopathy.
Better physicians’ knowledge of such an occupational
injury would undoubtedly lead to early recognition of the
problem, so decreasing workers’ impairment and reducing legal claims.
A comprehensive approach to the management of
retinal lesions should acknowledge both the individual
and organizational levels of intervention. Preventive
strategies should include good welding equipment,
environmental background lighting, eye protection
redesign and training of workers. Workers should be
adequately informed about the danger of welding too
close to the eyes and of looking round the side of the visor,
even for a very short period. Workers should be advised to
avoid ingestion of photosensitizing drugs, such as hydrochlorothiazide, furosemide, allopurinol, benzodiazepines
[15] and fluphenazine [6], while welding. Early diagnosis
of radiation retinopathy may be useful in reducing
macular oedema by photocoagulation treatment [16], so
improving vision in eyes with welders’ maculopathy.
References
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1988; 72: 570–575.
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