Early and late spectral domain optical coherence tomography features of acute welding maculopathy.

Electrical welding arcs emit an intense and extended spectrum of radiation ranging from infrared to ultraviolet. The cornea and lens absorb the ultraviolet range giving rise to painful keratoconjuntivitis.1-3 Radiation in the visible and near infrared range (400-1400 nm wavelength) penetrates deep into the eye and, if sufficient in intensity, may damage the retina.

Although welding induced photic retinal injury is rare, welders have a risk of phototoxic maculopathy. Infrared absorbing green glass filters placed within the welder's helmet protects ocular tissues from welding arc radiation.4

Some reports have already described optical coherence tomography (OCT) features of acute or chronic welding maculopathy.5-8 Herein, we report early and late spectral domain OCT (SD-OCT) features in a case of bilateral welding maculopathy.

A 25-year-old welder presented with visual blurring 3 days after arc welding. Past medical history was unremarkable. He had been exposed to welding arc light for a brief period of time, i.e. less than 30 seconds while using sunglasses, assuming that ordinary sunglasses are effective protection against welding light. Best corrected visual acuity was 5/10 in both eyes. The patient did not complain of ocular pain or injection. Dilated fundus examination revealed mild foveal pigmentary changes while other examinations were unremarkable.

SD-OCT revealed a preserved foveal contour and normal vitreoretinal interface. A region of hyporeflectivity was evident disrupting the inner segment/outer segment (IS/OS) line. This hyporeflectivity had created cyst like spaces between the external limiting membrane and the retinal pigment epithelium (RPE) in the left eye (Figure 1).

Figure 1

Upper and lower optical coherence tomography images (right and left eyes, respectively) show inner segment/outer segment disruption creating cyst like lesions in the left eye.

Six months later BCVA was 6/10 in both eyes and fundus examination revealed a round dark-yellow central macular lesion. SD-OCT at this time revealed disruption of the IS/OS line (Figure 2).

Figure 2

Fundus photography and optical coherence tomography images of the right and left eyes 6 months after welding induced maculopathy showing disruption of inner segment/outer segment line.

DISCUSSION

High resolution OCT in our patient revealed disruption in the IS/OS layer which correlated with decreased visual acuity. These findings are similar to our previous report on OCT findings in solar retinopathy.9

In contrast to our case, Choi and Cellini5,8 reported no OCT findings in acute welding retinopathy, which may be related to difference in light intensity and protection. After one month, hyperreflectivty in the external limiting membrane on OCT became apparent in their patients.8

Yang et al, reported OCT findings of chronic welding arc maculopathy as interruption in the IS/OS layer and the inner portion of the RPE in 30 welder eyes.6 Pilli et al, also reported discontinuity of photoreceptor IS/OS junction in welding arc maculopathy.7

Our case had only brief exposure to welding light using only ordinary sunglasses, assuming it was effective protection. Despite absorption of ultraviolet light by sunglasses protecting from actinic keratitis, the infrared spectrum of emitted light resulted in thermal and photochemical macular damage. This damage was clearly manifest on high resolution OCT images as IS/OS interruption.

This report emphasizes the importance of using standard protective devices for occupations exposed to high intensity light sources such as welding, even if exposure is very brief.