Purpose
To characterize a large single-center series of retinal injuries in children secondary to handheld laser devices, with emphasis on potential prognostic factors.
Design
Retrospective case series.
Methods
Sixteen children (24 eyes) with retinal injuries secondary to handheld lasers were identified from our electronic patient record system. Case notes, digital fundus photography, and spectral-domain optical coherence tomography images were reviewed.
Results
The mean age of affected children was 12.7 years (range 9–16 years), with 12 male and 4 female subjects. Mean follow up was 5.4 months (range 1–23 months). Five children (31%) were referred as suspected retinal dystrophies. The mean logMAR visual acuity at presentation was 0.30 (20/40) (range −0.20 [20/12.5] to 1.6 [20/800]). Eleven children (69%; 15 eyes) had “mild” injuries with focal retinal disruption confined to the photoreceptor and ellipsoid layers; such injuries were associated with a better prognosis, the mean visual acuity at presentation being 0.10 (20/25). “Moderate” injuries were seen in 3 eyes of 2 children, with retinal disruption confined to the outer retinal layer but diffuse rather than focal in nature. Three patients (4 eyes) had “severe” injuries, with subfoveal outer retinal architecture loss and overlying hyperreflective material in inner retinal layers.
Conclusion
Retinal injuries secondary to handheld laser devices may be difficult to diagnose and are likely underreported. It is important that such data are in the public domain, so regulatory authorities recognize the importance of laser retinopathy as an avoidable cause of childhood visual impairment and take steps to minimize the incidence and impact of laser injuries.
There are increasing reports of retinal injuries secondary to handheld lasers, with cases found across the world. These handheld lasers often resemble laser pointers, although they are commonly marketed as toys. Although certain safeguards exist to protect consumers (ie, Food and Drug Administration [FDA] safety notification in the United States and BS EN 60825-1:2014 in the United Kingdom), these are difficult to police, as devices are often purchased outside the country of use, and often from an online retailer. Moreover, labeling of laser devices may be misleading.
Most descriptions of retinal injuries secondary to handheld laser devices come from single case reports, or relatively small case series, so the retinal damage is not well characterized. Additionally, such laser devices are attractive to children, who may give a vague history following an injury or deliberately withhold information for fear of being punished. The diagnosis may be missed unless specific questions about access to such lasers are asked.
In the acute phase, several reports describe a “vitelliform-like” maculopathy, resolving to leave a laser “scar.” Alsulaiman and associates describe 17 patients who sustained macular holes following exposure to high-power blue handheld lasers, while Yiu and associates describe preretinal macular haemorrhages. The visual impact of these retinal laser injuries is variable, with some reports describing severe, long-term effects on visual function, while other injuries resolve to near-normal levels of visual acuity, although more subtle visual deficits may remain.
The aim of this study was to characterize a relatively large series of children seen at a single center, who sustained retinal injuries secondary to handheld laser devices. We describe common features in the presentation of patients and the clinical spectrum of injury, as well as the appearance of injuries on spectral-domain optical coherence tomography (OCT) and the visual outcome. Our findings should aid early diagnosis, improve patient counseling and advice on prognosis, and provide data that regulatory authorities might use to better protect children from retinal damage and potential long-term visual impairment.
Methods
Approval to undertake this observational case series was obtained by our institutional review board at Moorfields Eye Hospital NHS Foundation Trust. In line with our institutional policy, consent was not specifically sought, owing to the retrospective nature of the study and the fact that all data were anonymized. Patients with retinal injuries secondary to handheld laser devices were identified by searching our electronic patient record system at Moorfields Eye Hospital (London, UK) between January 1, 2011 and June 30, 2015. A retrospective case-notes review was undertaken for patients identified, as well as a review of retinal imaging. Patients underwent pupillary dilation before OCT and fundus autofluorescence (FAF) imaging, using a Spectralis FAF + OCT device (Heidelberg Engineering, Heidelberg, Germany). Statistical analysis was undertaken using an Excel spreadsheet.
Results
We identified 16 children (24 affected eyes), with retinal injuries secondary to laser devices. Of these, 12 (75%) were male and 4 were female. The mean age was 12.7 years (range 9–16 years). There were 8 (50%) bilateral cases. All affected children were from the United Kingdom, although 5 of the cases (31%) were injuries sustained abroad; in 2 cases the exposure occurred in China, 1 case in Greece, and 1 in France, with the fifth case documented only as “abroad.” Clinical findings are summarized in the Table .
| Clinical Feature | Finding (N =16 Children) |
|---|---|
| Sex | 12 male (75%); 4 female (25%) |
| Laterality | Unilateral 8 (50%); bilateral 8 (50%) |
| Age (range) of affected children | 12.7 years (range 9–16 years) |
| Laser exposure | Admitted direct exposure 8 (50%); admitted indirect exposure 7 (44%); denied laser exposure 1 (6%) |
| Wavelength of laser device | Green 5 (31%); red 1 (6%); unknown 10 (63%) |
| Clinical symptoms | Central scotoma 11 (69%); blurred vision 3 (19%); asymptomatic 2 (12%) |
Features in the Clinical History
A delay in the diagnosis of a laser injury was a common feature among our patients. Five children (31%) were referred for a specialist opinion with suspected retinal dystrophies. Best disease was thought to be the likely diagnosis in 3 cases and Stargardt disease was suspected in 1 child. One child had been seen in an ocular genetics clinic but had not received any formal diagnosis. Furthermore, children frequently denied exposing themselves to a laser pointer or having a laser shone into their eyes when asked, with only 8 (50%) children admitting this (in 1 case this admission occurred 7 months after first consultation). A further 7 children admitted that they had played with a laser toy, or their parents admitted that they had kept a laser toy in the house. One child, with a retinal appearance that strongly suggested a laser injury ( Figure 1 ), to date has denied laser exposure. In 5 cases (31%), the causative laser was a green laser; in 1 other known case the causative laser was red.
The most commonly encountered symptom was a central scotoma (11 children, 69%), followed by blurred vision (3 children, 19%). Two children (12%) were asymptomatic and referred because their optometrist noted macular changes. The mean follow-up period was 5.4 months (range 1–23 months).
Examination and Imaging Findings
The mean logMAR visual acuity at presentation was 0.30 (20/40) (range −0.20 [20/12.5] to 1.6 [20/800]). A wide spectrum of retinal appearances was encountered. OCT imaging was available for 15 patients (94%); 1 child was seen in our emergency department with a retinal laser injury that had been diagnosed in another department and no OCT images were taken at this visit. Thus in 2 eyes OCT classification of the injury was not possible.
Injuries were classified as “mild” if they were focal in nature, with small discrete outer retinal and retinal pigment epithelium (RPE) disturbance at the macula; a typical macular appearance is shown in Figure 2 . OCT imaging in these injuries confirmed the presence of focal retinal disruption confined to the photoreceptor and ellipsoid layers. Eleven children (69%), corresponding to 15 eyes, had mild injuries. The mean visual acuity in this subset was 0.10 (20/25) (range −0.20 [20/12.5] to 0.60 [20/80]). One patient in this group with a unilateral injury had a “microhole” appearance with focal loss of subfoveal photoreceptors; the visual acuity was 0.20 (20/32) in this child. The majority of injuries in this category were unilateral (8, 80%). One child with a mild retinal injury in 1 eye had a “severe” retinal injury in the other.
Injuries were considered “moderate” if retinal disruption was confined to the outer retinal layer but diffuse rather than focal in nature ( Figure 3 ). Three eyes of 2 children had a moderate-severity injury. One child had bilateral moderate-severity injury. This child was resident in China at the time of injury, but returned to the United Kingdom for further management. When he was seen in our unit, his visual acuities were 0.48 (20/60) and 0.96 (20/180) in the right and left eyes, respectively. The other child had a moderate-severity injury in the left eye with a logMAR visual acuity of 1.14 (20/320) and a severe injury in the other eye (see below).
Three patients (4 eyes) had severe injuries, with subfoveal loss of outer retinal architecture and overlying hyperreflective material in inner retinal layers ( Figure 4 ). These injuries were associated with worse vision, the mean logMAR visual acuity being 1.1 (20/250) (range 0.80 [20/125] to 1.6 [20/800]). One patient had bilateral severe injuries, 1 child had a severe injury in 1 eye and a moderate injury in the other ( Figure 1 ) and 1 child had a severe injury in the left eye with a visual acuity of 1.6 (20/800) and a mild injury in the other eye with a visual acuity of 0.0 (20/20).
