Case Series of Retinal Damage Caused by Laser Pointer

The threshold for laser-induced retinal damage is dependent primarily upon the laser wavelength and the exposure duration. The study of the wavelength dependence of the retinal damage threshold has been greatly enhanced by the availability of tunable lasers. The Optical Parametric Oscillator (OPO), capable of providing useful pulse energy throughout a tuning range from 400 nm to 2200 nm, made it possible to determine the wavelength dependence of laser-induced retinal damage thresholds for q-switched pulses throughout the visible and NIR spectrum. Studies using the a tunable TI:Saph laser and several fixed-wavelength lasers yielded threshold values for 0.1 s exposures from 440 nm to 1060 nm. Laser-induced retinal damage for these exposure durations results from thermal conversion of the incident laser irradiation and an action spectrum for thermal retinal damage was developed based on the wavelength dependent transmission and absorption of ocular tissue and chromatic aberration of the eye optics. Long (1-1000s) duration exposures to visible laser demonstrated the existence of non-thermal laser-induced retinal damage mechanisms having a different action spectrum. This paper will present the available data for the wavelength dependence of laser-induced thermal retinal damage and compare this data to the maximum permissible exposure levels (MPEs) provided by the current guidelines for the safe use of lasers.

Retinal damage induced by mechanical trauma, ischemia or laser photocoagulation increases considerably by secondary degeneration processes. The spread of damage may be ameliorated by neuroprotection that is aimed at reducing the extent of the secondary degeneration and promote healing processes. Hyperbaric oxygen (HBO) treatment consists of inspiration of oxygen at higher than one absolute atmospheric pressure. Improved neural function was observed in patients with acute brain trauma or ischemia treated with HBO. This study was designed to evaluate the neuroprotective effect of hyperbaric oxygen (HBO) on laser induced retinal damage in a rat model. Standard argon laser lesions were created in 25 pigmented rats divided into three groups: Ten rats were treated immediately after the irradiation with HBO three times during the first 24 hr followed by 12 consecutive daily treatments. Five rats received a shorter treatment regimen of 10 consecutive HBO treatments. The control group (10 rats) underwent the laser damage with no additional treatment. The retinal lesions were evaluated 20 days after the injury. All outcome measures were improved by the longer HBO treatment (P<0.01). The shorter HBO treatment was less effective, showing an increase only in nuclei density at the central area of lesion (P< 0.01). Hyperbaric oxygen seems to exert a neuroprotective effect on laser-induced retinal damage in a rat model. In the range of HBO exposures studied, longer exposure provides more neuroprotection. These results encourage further evaluation of the potential therapeutic use of hyperbaric oxygen in diseases and injuries of the retina.

Objective: To describe the phenotypes associated with laser-induced retinal damage in children.Methods: Five patients with maculopathy and reduced visual acuity associated with laser pointer use were evaluated. Best-corrected visual acuity, retinal structure, and function were monitored with color fundus, infrared (IR), and red-free images, fundus autofluorescence (AF), spectral domain-optical coherence tomography (SD-OCT), and full-field electroretinography (ERG).Results: All five laser pointer injury patients had retinal lesions resembling a macular dystrophy (one bilateral and four unilateral). These lesions were irregular in shape but all had a characteristic dendritic appearance with linear streaks radiating from the lesion. Photoreceptor damage was present in all patients, but serial OCT monitoring showed that subsequent photoreceptor recovery occurred over time in the eyes of at least four patients. One patient also had bilateral pigment epithelial detachments (PED). Both hyper- and hypoautofluorecence were observed in the laser damage area.Conclusions: In general, OCT and IR images are quite useful to diagnose laser damage, but AF is not as sensitive. Laser pointer damage in children can occasionally be misdiagnosed as a macular dystrophy disease, but the distinctive lesions and OCT features are helpful for differentiating laser damage from other conditions.

The laser bioeffects team at Brooks Air Force Base has extensively studied the mechanisms for retinal damage to laser exposures shorter than one nanosecond. This regime, called the ultrashort regime, has novel new mechanisms for retinal damage. In previous work in the nanosecond regime we have shown that the threshold for laser-induced breakdown is higher than the threshold for ophthalmoscopically visible retinal damage. But, as the pulse duration is reduced into the femtosecond regime, the laser-induced breakdown threshold and retinal damage threshold approach each other. We discuss the most recent data collected for sub-50 fs laser induced breakdown thresholds and retinal damage thresholds. With these short pulse durations, the chromatic dispersion effect on pulse chirp should be considered to gain a full understanding of the mechanisms for damage. We discuss the most likely damage mechanisms operative in this pulse width regime and discuss relevance to laser safety.The laser bioeffects team at Brooks Air Force Base has extensively studied the mechanisms for retinal damage to laser exposures shorter than one nanosecond. This regime, called the ultrashort regime, has novel new mechanisms for retinal damage. In previous work in the nanosecond regime we have shown that the threshold for laser-induced breakdown is higher than the threshold for ophthalmoscopically visible retinal damage. But, as the pulse duration is reduced into the femtosecond regime, the laser-induced breakdown threshold and retinal damage threshold approach each other. We discuss the most recent data collected for sub-50 fs laser induced breakdown thresholds and retinal damage thresholds. With these short pulse durations, the chromatic dispersion effect on pulse chirp should be considered to gain a full understanding of the mechanisms for damage. We discuss the most likely damage mechanisms operative in this pulse width regime and discuss relevance to laser safety.

Increasing Eye Injuries Following Exposure to Laser Beams, the Silent Epidemic

NAP is the smallest active element of activity-dependent neuroprotective protein (ADNP) in the non-myelinated neural tissue. This study evaluated the neuroprotective effect of NAP in reducing the spread of laser-induced retinal damage in rat. Laser lesions were created in 72 DA pigmented rats. Two groups were treated by one intravenous or intravitreal injection of NAP immediately after exposure to laser. Two control groups were similarly administered saline injection. Histological and morphometrical evaluations of the lesions were preformed 3, 20 and 60 days after photocoagulation. After intravitreal treatment with NAP, a significant reduction in the diameter of the laser-induced lesions was found 3 days after photocoagulation (p < 0.001) but not after 20 and 60 days while the systemic treatment significantly reduced lesion diameter 20 and 60 days after photocoagulation (p = 0.001). Significant difference in photoreceptor cell loss was found in eyes treated intravitreally only 3 days after photocoagulation (p = 0.002). In the systemically treated animals such effect was found only after 20 and 60 days (p < 0.001). Treatment with NAP ameliorates laser-induced retinal lesions. Intravitreal treatment had an early short-term effect while the effect of systemic administration was delayed and prolonged. This treatment may be of clinical significance in reducing laser-induced retinal injuries in humans.

In this paper, we describe a military laser accident case where bilateral Q-switched laser exposure resulted in bilateral macular damage with immediate visual acuity loss in one eye (OS) and delayed visual acuity loss in the other exposed eye (OD), where retinal damage appeared more parafoveal. At 6 weeks post exposure, OS had recovered to 20/17 and OD had dropped to 20/100 Snellen activity. Retinal nerve fiber damage was observed in both eyes at this time. Contrast sensitivity measurements made in OS were suppressed across all spatial frequencies, even though Snellen acuity measured in the normal range. More severe high spatial frequency loss in contrast was measured in the right eye as well as low spatial frequency loss. Both OS and OD revealed a parafoveal preferred retinal locus with scanning laser ophthalmoscopy contrast sensitivity measurements, suggesting parafoveal retinal compensatory processes.

In recent years, an increasing incidence of laser pointer-associated retinal injuries has been observed, likely due to easy access to incorrectly classified laser pointers, their labelling as toys, and lack of awareness concerning the associated risk. Laser pointer exposure can lead to irreversible retinal damage and associated vision loss, depending on the wavelength, radiation power, duration of exposure, localization, and spot size. Pronounced retinal laser damage is especially seen in children and teenagers. The structural appearance of retinal laser pointer damage varies and, in some cases, may be a diagnostic challenge. Besides often subtle findings on optical coherence tomography examination, characteristic alterations on near-infrared autofluorescence imaging may be valuable for the diagnosis of retinal laser pointer injuries and for differentiating other retinal lesions with similar appearance. The increase in laser pointer injuries indicates that regulatory actions and increased public awareness are required regarding the dangers of laser pointers.

To explore the clinical features of laser pointer-related retinal injuries among children and gain insight into the general public awareness around laser pointer use. This was a retrospective case series of 9 children (12 eyes) with laser pointer-related retinal injury from a United Kingdom tertiary ophthalmology unit and a prospective survey of laser pointer use and awareness among children and parents presenting to the hospital eye service for other eye conditions. Within the case series, 67% of patients were asymptomatic on presentation. A mean follow-up of 25.6 months showed that structural changes persisted in all cases, and in one case, there was progression in the macular lesion size. One case presented with secondary choroidal neovascular membrane, requiring intravitreal anti-vascular endothelial growth factor injections. A survey showed that 9% of children admitted to having played with laser pointers and 13% of parents were aware of their children playing with laser pointers. Only one-third of children and parents were aware of laws regulating laser pointers. Most parents (96%) agreed that there needs to be increased awareness regarding laser pointers' effect on vision. This study has highlighted that although children may be asymptomatic at presentation, there is usually permanent structural damage to the macula, and complications such as secondary choroidal neovascular membrane can develop years later. The survey found a relatively high incidence of laser pointer use with little awareness of the regulation laws. There is an urgent need to establish more robust measures to improve public awareness and regulations around laser pointers. [J Pediatr Ophthalmol Strabismus. 2023;60(1):52-59.].

The retinal damage induced by laser photocoagulation increases considerably by the secondary degeneration process whereby tissues adjacent to the primary lesion are destroyed. As the neuroprotective effect of immunization by PN-277 was previously demonstrated in models of retina, optic nerve, brain, and spinal cord lesions, it may be used also for reducing retinal damage induced by laser. The aim of this study was to evaluate the neuroprotective effect of immunization with PN-277 in reducing the spread of laser-induced retinal damage. Standard argon laser lesions were created in 36 DA pigmented rats. Seven days before exposure to laser, the rats were divided into a test group (n = 18) that was pre-immunized with intraperitoneal injection of PN-277 and control group (n = 18) treated with saline. Histological and morphometrical evaluations of the retinal lesions were preformed 3, 20, and 60 days after the injury. Significant ameliorative effect was demonstrated in the retinas of the pre-immunized animals 60 days after exposure to laser. The diameter of the lesion was 356 microm as compared with 406 microm (P < 0.01), the cell density of the photoreceptor cell bodies measured in the whole lesion was 72.4% of normal as compared with 64.5% (P = 0.01), and at the center of the lesion it was 57.3% of normal as compared with 38.2% (P < 0.01) (treated and control groups, respectively). Immunization with PN-277 has an ameliorative effect in neural tissue such as the retina. This type of immunization may be of clinical significance in reducing laser-induced retinal injuries in humans.

For over five decades, laser-induced retinal damage (LIRD) was thought to be the necessary cost of all therapeutic effects of laser treatment for the most important causes of irreversible visual loss, the chronic progressive retinopathies (CPRs). The development of modern retinal laser therapy with the discovery of “low-intensity/high-density subthreshold micropulse” laser (SDM) showed that the supposed need for LIRD represented a case of confusing association with causation. This revealed that LIRD was unnecessary and detrimental to clinical outcomes, and thus, contraindicated as the most severe complication of retinal laser treatment. SDM allowed for an understanding of the mechanism of retinal laser treatment as a physiologic reset effect, triggered by heat-shock protein (HSP) activation upregulating the unfolded protein response and restoring proteostasis by increasing protein repair by 35% in dysfunctional cells via a thermally sensitive conformational change in the K10 step of HSP activation kinetics. Because HSP activation kinetics are catalytic, even low levels (the “reset” threshold) of HSP activation result in a maximal treatment response. SDM and the study of HSP activation kinetics in the retina show that the therapeutic effects of retinal laser treatment can be fully realized without any degree of LIRD. Besides LIRD, all effects of retinal laser treatment are restorative and therapeutic, without any known adverse treatment effects. Without LIRD, the benefits of retinal laser treatment are infinitely renewable and direct treatment of the fovea is possible. Elimination of LIRD from retinal laser treatment has revolutionized the clinical potential of retinal laser treatment to broaden treatment indications to permit, for the first time, effective early and preventive treatment to reduce visual loss from the most frequent causes of irreversible visual loss worldwide, the CPRs.

Exogenously induced retinopathies can be caused by consumation of stimulating substances, systemic or ocular medications, vaccinations, light or irradiation. Some of the effects are transient, whereas other effects induce irreversible toxic reactions. Retinal damage may develop either acutely with obvious relation to the damaging cause, but often may take a long duration of repeated use of a substance or medication. External stimulants (e.g. nicotine, alcohol, poppers, methanol) are the most frequent cause of exogenously induced retinal damage. Side effects from systemic drugs (e.g. hydroxychloroquine, ethambutol, MEK-, ERK-, FLT3-, checkpoint inhibitors, didanosin, pentosanpolysulfat sodium) or intravitreally applied drugs (e.g. antibiotics, VEGF-inhibitors) are less frequent. Ocular side effects associated with vaccinations are rare. Ambient light sources induce no damaging effects on the retina. Incorrect use of technical or medical light sources (e.g. laser pointers) without adherence to safety recommendations or unshielded observation of the sun might induce permanent retinal damage. Local or external irradiation might induce retinal vascular damage resulting in radiation retinopathy.

Bilateral macular hole from a handheld laser pointer

Purpose: Laser pointer retinopathy is a condition increasing in prevalence due to poor education of proper laser use at the childhood/teenage level and poor awareness of risks and complications of laser pointers among the adult population. Eye care physicians can serve as an important bridge among these populations to help increase awareness and promote and educate patients on the potentially damaging retinal effects associated with laser pointer viewing/exposure. Pathophysiology, signs and symptoms, multimodal imaging interpretation, and treatment management options of laser pointer retinopathy are reviewed through a case study. Background: A 19-year-old male presented to the eye clinic without any ocular or visual complaints for a routine eye examination. Fundus examination revealed yellow subfoveal scarring in the left eye and corresponding damage to the foveal ellipsoid zone on optical coherence tomography imaging. Amsler grid findings further confirmed metamorphopsia that was present only in the left eye. Further questioning determined the foveal damage to be laser pointer retinopathy secondary to extended laser pointer viewing. Conclusions: Laser pointer retinopathy is an increasingly prevalent retinal finding in younger populations. In most cases vision loss slowly improves with time, but the retinal damage has often been reported to be irreversible. Considering this information, it is imperative for optometrists to educate school staff, parents and children of the permanent ocular damage that can occur with laser pointer viewing and promote safe practices. CE Notification: This article is available as a COPE accredited CE course. You may take this course for 1-hour credit. Read the article and take the qualifying test to earn your credit. Click here to Enroll (https://www.crojournal.com/laser-pointer-retinopathy-a-case-report-and-review)

Laser pointers were banned in a Wisconsin public school district after a teacher and student “suffered serious eye injuries.1 ” A female student reportedly could no longer see the color red in one eye, and a male teacher reported serious vision loss in one eye as a result of direct ocular exposure to the laser beam. Laser pointers are available from many vendors and are commonly used in educational institutions and industry by persons who have little understanding of the potential for laser injury. The results of further investigation into this particular incident will be presented.Laser pointers were banned in a Wisconsin public school district after a teacher and student “suffered serious eye injuries.1 ” A female student reportedly could no longer see the color red in one eye, and a male teacher reported serious vision loss in one eye as a result of direct ocular exposure to the laser beam. Laser pointers are available from many vendors and are commonly used in educational institutions and industry by persons who have little understanding of the potential for laser injury. The results of further investigation into this particular incident will be presented.