Assessment of Alleged Retinal Laser Injuries

SPECIAL ARTICLE Assessment of Alleged Retinal Laser Injuries

Martin A. Mainster, PhD, MD; Bruce E. Stuck, MS; Jeremiah Brown, Jr, MD, MS

ccidental retinal laser injuries are easily diagnosed when there are known laser sources, typical macular injuries, and visual deficits consistent with retinal findings. Decisions are more difficult when retinal findings are subtle or absent, despite reported visual problems and somatic complaints. Inaccurate diagnosis of an ocular laser injury can precipi- tateA a costly, lengthy sequence of medical and legal problems. Analysis of laser-tissue interactions and the characteristics of unambiguous retinal laser injuries provide 6 key questions to facilitate difficult diagnoses. Case reports demonstrate the usefulness of answering these questions before making diagnostic decisions. Retinal laser lesions that cause serious visual problems are readily apparent ophthalmoscopically and angiographically. Accidental, intentional, or clinical retinal laser lesions do not cause chronic eye, face, or head pains. Diagnosis of a retinal laser injury should be evidence based, not a matter of conjecture or speculation. Arch Ophthalmol. 2004;122:1210-1217

It is well understood that accidental momen- tion (700-10000 nm) can damage the eye.6-9 tary exposure to an ordinary flashlight beam Transmission and absorption of optical ra- is annoying but safe. Accidental momentary diationbyocularmediadependonthewave- exposure to a low-power laser pointer beam length of the incident UV radiation, visible is also annoying but safe, yet it can evoke fear light, or infrared radiation.10 Wavelength, or outrage in some people.1-5 Untoward re- pulse duration, spot size, and irradiance sponses to real or imagined laser exposures (power density, or laser power divided by can have complex social and psychiatric ex- area) determine the magnitude and lateral planations or more practical fiscal motiva- extent of temperature rises in exposed tis- tions. Ophthalmologists may be called on sue produced by incident laser beams.11,12 to determine whether a retinal laser injury is responsible for symptoms that reportedly CME available at follow an actual or perceived laser exposure www.archophthalmol.com incident. The proper analysis of those situ- ations requires a clear understanding of the Cornea and lens refraction produce retinal organic and psychophysical consequences irradiances for laser beams that are up to 105 ofactuallaserinjuries,particularlywhenreal timesgreaterthantheircornealirradiances.13 butunrelatedophthalmicandsystemicprob- Laser radiation can damage the eye by pho- lems are present to confound the analysis. tomechanical,photothermal,orphotochemi- cal mechanisms.8,9,14-16 It is useful to differ- LASER EFFECTS entiatebetweenthesemechanisms,butmore than one effect may be involved in any par- ExposuretoUVradiation(200-400nm),vis- ticular injury. ible light (400-700 nm), and infrared radia- Photomechanical injuries are caused by extremely high laser irradiances in very brief laser exposures ranging from hun- From the Department of Ophthalmology, University of Kansas Medical School, Kansas −15 City (Dr Mainster); the United States Army Medical Research Detachment, Walter dreds of femtoseconds (10 seconds) to −6 Reed Army Institute of Research, Brooks Air Force Base, Tex (Mr Stuck and microseconds (10 seconds). Tissue is Dr Brown); and Ophthalmology Associates, Nix Medical Center, San Antonio, Tex fragmented, perforated, or distorted im- (Dr Brown). The authors have no relevant financial interest in this article. mediately by a photomechanical injury.

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Figure 1. A mild accidental laser injury. A 21-year-old female technician accidentally looked into the exit aperture of a repetitively pulsed infrared Nd:YAG 1064-nm target designation laser. The technician reported seeing 2 or 3 yellowish flashes at the time of the laser exposure. Visual acuity in her left eye was 20/50 a few hours after the accident and 20/200 two days later; visual acuity returned to 20/15 two months after the injury. A, Four days after the accident, there is foveal edema, surrounding subretinal hemorrhage, and several small, hypopigmented retinal pigment epithelium lesions. B, One month after the accident, foveal edema and subretinal hemorrhage have resolved, and a small area of foveal retinal pigment epithelium degeneration has developed.

Clinical examples include photodis- Photochemical injuries occur Laser eye injuries can be pre- ruption in Nd:YAG laser capsu- when prolonged optical radiation ex- vented by appropriate laser safety lotomy, photoablation in excimer la- posure causes phototoxic chemical eyewear use. Unfortunately, laser ser keratorefractive surgery, and reactions in affected tissues8,16,35-37 or safety glasses or goggles partially re- photovaporization in holmium: when a previously administered ex- strict vision, interfering with visu- YAG laser thermokeratoplasty for ogenous photosensitizer is acti- ally demanding laboratory, indus- hyperopia. Powerful Q-switched in- vated by an appropriate light trial, or military tasks. In addition, dustrial or military lasers can cause source.38 Clinical examples include laser safety goggles can be uncom- severe retinal injuries when their solar and operating microscope fortable and can fog in hot and hu- radiation is absorbed in the retinal maculopathy and verteporfin pho- mid environments. Most industrial pigment epithelium (RPE) and un- todynamic therapy for age-related accidents occur when a misfired la- derlying choroid.17-23 In typical, ac- macular degeneration. Viewing in- ser beam enters an unshielded by- cidental retinal injuries, rapid tis- tense light is very uncomfortable. stander’s eye. Military injuries typi- sue expansion causes hemorrhage Natural protective responses, such cally occur when a laser rangefinder and prominent, permanent retinal as squinting, pupillary constric- or target designator beam is inad- scars. tion, and looking away from uncom- vertently or inappropriately viewed Thermal laser injuries are pro- fortably brilliant light sources, pro- by an unprotected user or onlooker duced by high laser irradiances in tect people from phototoxic retinal (Figure 1 and Figure 2).46,47 An brief exposures ranging from micro- injuries, except in highly unusual, ordinary laser pointer is safe, un- seconds to several seconds. Tissue prolonged viewing circumstances, less a user chooses to stare at its un- protein coagulation often causes im- such as unprotected solar eclipse ob- comfortable brilliant light for more mediate or delayed blanching of the servation or welding arc viewing with than 10 seconds at close range, de- laser impact site and adjacent tis- a defective protective filter.6,9,39 spite eye hazard labels warning us- sue. Clinical examples include ar- ers to avoid eye exposure.1-5 Ante- gon laser panretinal photocoagula- ACCIDENTS rior segment eye injuries from lasers tion and trabeculoplasty. Barely are rare because UV and infrared la- visible retinal photocoagulation le- It is estimated that fewer than 15 reti- sers that produce radiation with con- sions are associated with retinal tem- nal injuries worldwide each year are siderable corneal or crystalline lens perature increases of 10°C.12,24-28 caused by industrial and military la- absorption are typically used in well- Typical clinical photocoagulation le- sers.17,22,40-44 In most actual laser eye controlled medical or industrial de- sions are associated with much injuries, the laser source is known, vices or environments. Most ocular higher retinal temperature in- typical chorioretinal damage oc- laser accidents are caused by pow- creases (40°C-60°C).12,24,27,28 Acci- curs, there is an unambiguous tem- erful Q-switched lasers that pro- dental cornea, iris, and crystalline poral relationship between a laser in- duce serious retinal injuries.19,20,22,42 lens injuries have been reported in cident and the onset of visual 29-34 clinical photocoagulation. Acci- abnormalities that are well corre- SYMPTOMS AND FINDINGS dental retinal laser lesions that pro- lated with retinal findings, and reti- duce substantial vision loss are nal abnormalities remodel after the The severity of initial vision loss af- apparent ophthalmoscopically or incident in a manner commensu- ter a retinal laser injury depends on angiographically.17-23 rate with their severity. the distance of the laser impact site

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©2004 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/02/2021 from the center of the fovea, the ex- A tent of chorioretinal disruption, and the amount of chorioretinal bleed- ing. Victims of visually significant retinal laser injuries typically expe- rience sudden, severe decreased vision in one or, less commonly, both eyes. They usually notice a bright flash of light even with invisible laser beams, followed by an immediate decrease in the vision of affected eyes. They occasionally hear a loud popping sound during a Q-switched chorioretinal laser injury. Vision may improve over several days to months. Visual prognosis is excellent if retinal findings are minor or do not in- volve the fovea. If the results of Am- sler grid testing are abnormal, findings stabilize within a few months. These findings are consistent, stable, and well correlated with retinal findings B in cooperative patients. Momentary pain may occur at the time of ocular laser injury, but only rarely. This pain does not persist, just as it does not persist after clinical retinal photocoagulation. Noninjurious laser exposures and most laser injuries are painless, but rubbing an eye after a laser exposure can cause a painful transient corneal abrasion that individuals may attribute to laser exposure. Self- inflicted corneal abrasions are responsible for reported painful vision losses in children after laser pointer exposures.5 The most common initial clinical finding after an industrial or military Q-switched laser injury is prominent vitreous and/or chorioretinal hemorrhage from blood ves- C sels ruptured by tissue distortion (Figure 2).17,20-22,40 The number and size of blood vessels damaged at the laser impact site determine the extent of initial hemorrhage.23 The location of the vessels and the structural integrity of adjacent tissue determine how effectively blood is tamponaded locally.23 Large retinal areas can be rendered dysfunc- Figure 2. A severe accidental laser injury. A 20-year-old male technician deliberately viewed the output of a laser rangefinder despite reading warning labels and undergoing laser safety training. He reported tional if blood spreads laterally into immediate vision loss in his right eye, with some improvement after 5 minutes. He sought medical subhyaloid, subretinal, or sub-RPE assistance 18 hours after the injury, at which time visual acuity was 20/150 OD, where there was a macular spaces. Persistence of hemorrhage and vitreous hemorrhage. The vitreous hemorrhage cleared, and his visual acuity returned to 20/70 during into subretinal spaces can cause pho- the next month. After the accident, visual acuity was 20/40 OD at 1 year and 20/30 OD at 2 years. A, Ten 48 weeks after the injury, there is a full-thickness macular hole with surrounding retinal pigment epithelium toreceptor deterioration. Retinal depigmentation in the right eye. B, Fluorescein angiography documents a prominent foveal window defect holes and scarring can occur at the due to retinal pigment epithelium atrophy. C, Optical coherence tomography documents a macular hole with impact site (Figures 1 and 2).17,20-22,40 increased reflectivity at its base. This increased reflectivity is a characteristic of laser-induced macular holes.45 It is caused by choriocapillaris scarring, so the prognosis for visual improvement after macular Fundus photography, fluores- surgery may be worse for laser-induced than idiopathic macular holes.45 cein angiography, and optical co-

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©2004 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/02/2021 herence tomography are invalu- able for determining whether retinal Six Questions That Facilitate the Diagnosis of Alleged Retinal Laser Injuries injury is present after a laser incident and, if so, whether visual com- 1. Are there ocular abnormalities that could have been caused by a known laser-tissue interaction at the time of the reported incident? plaints are consistent with documented retinal abnormalities. Acute 2. If the answer to 1 is “yes,” have those abnormalities been documented by a reliable technique, such as fundus photography, fluorescein angiography, or optical coherence tomography? photomechanical injuries typically 3. If the answers to 1 and 2 are “yes,” do findings from ophthalmoscopy and retinal imaging evolve produce a hypofluorescent spot at after the incident in a manner consistent with a laser injury? the laser impact site caused by vit- 4. If the answer to 1 is “yes” and substantial visual or somatic complaints are present, is there any reous or associated chorioretinal scientific evidence that the objective ocular findings could cause the reported subjective hemorrhage. As the hemorrhage re- complaints? solves, a hyperfluorescent window 5. If the answer to 1 is “yes” and substantial visual complaints are present, is the location of defect may develop at the site ow- Amsler grid or visual field defects stable and consistent with the location of the retinal ing to RPE damage (Figure 2), with abnormalities supposedly responsible for causing them? hyperfluorescent staining of any fi- 6. If the laser source involved in the alleged injury is available or known, is it capable of producing brosis that develops after the in- the observed clinical findings under the reported exposure conditions? jury. An RPE discontinuity or eleva- tion is commonly seen on optical coherence tomograms immedi- ing, whereas an ordinary window de- of diagnosing an actual laser injury ately after and subsequent to pho- fect on an angiogram performed is directly proportional to its sever- tomechanical injuries (Figure 2). within a week of a laser incident is ity. The answers to 6 facilitating ques- Acute photocoagulation lesions typi- more likely to be due to previous tions are useful for diagnosing less se- cally have a hypofluorescent center trauma, inflammation, or other natu- vere or absent injuries after a real or with a surrounding ring of faint hy- ral processes. The possibility of pre- imagined laser accident (Table). If perfluorescence. If a photocoagula- existing or concurrent eye or sys- the answer to question 1 is “no,” then tion lesion is sufficiently small, there temic problems makes it important no visually significant laser injury has may be only a tiny hyperfluores- to obtain a complete medical his- occurred. If the answers to all 6 ques- cent spot at the injury site. Fluores- tory and review of systems in cases tions are “yes,” then a laser injury has cein leakage in the form of staining of possible retinal laser injury, in ad- almost certainly occurred. or pooling of dye at photocoagula- dition to carefully reviewing copies Proper evaluation of a laser in- tion sites in late angiogram frames of past medical records and retinal jury demands an exhaustive review is common immediately after an in- imaging if available. of systems and medical history to jury. Acute photochemical lesions Incidental angiographic find- rule out ocular or systemic causes for may have no angiographic abnor- ings should not be overinterpreted. the ophthalmic and somatic com- malities (as in mild solar maculopa- For example, tiny RPE window de- plaints ascribed to a purported la- thy) or early hyperfluorescence with fects occur routinely in angiograms ser exposure. In suggestible or oth- late leakage (as in operating micro- with normal findings. In a small se- erwise susceptible individuals, pain scope injuries).9 Visually signifi- ries of 50 consecutive fluorescein an- can represent an individual’s soma- cant phototoxic lesions eventually giograms reviewed by one of us tization of a perceived although not produce angiographically apparent (M.A.M.), two thirds of the contra- organic ocular injury. Differentiat- RPE abnormalities. lateral normal eyes of individuals with ing the psychiatric, financial, or Retinal photography and fluo- unilateral retinal problems had 1 or other origins of nonorganic disor- rescein angiography should be per- more tiny RPE window defects. The ders is a challenging problem,49-60 but formed as soon as possible after a RPE is its own record of a lifetime of perceived ocular injuries with no de- suspected laser injury because there infection, trauma, inflammation, and monstrable tissue damage are not may be subvisible lesions if laser ex- other natural events. A few scat- real laser injuries. posure variables are below thresh- tered RPE imperfections are neither olds for ophthalmoscopically appar- surprising nor conclusively diagnos- CASE REPORTS ent lesions. These tests are also tic of laser injury. important for dating chorioretinal CASE 1 findings and for determining DIAGNOSIS whether concurrent systemic dis- History ease rather than laser injury could The diagnosis of a laser injury can be their cause. Indocyanine green have considerable legal, financial, and An 11-year-old girl stared at a red la- angiography may also be useful, par- medical consequences. It should be ser pointer beam held close to her ticularly if it is performed using scan- based on objective medical evi- right eye for more than 10 seconds ning laser ophthalmoscopy. dence rather than on unscientific to satisfy the curiosity of class- If there is no vitreous and/or speculation. Medicolegal problems mates on a school bus who wanted chorioretinal hemorrhage to ob- arise when an injury is alleged but ob- to know if her pupil would con- scure the site, an acute laser injury jective findings are absent, within strict.61 She experienced no pain but is likely to produce a lesion with normal limits, or explainable by un- developed decreased vision and a some fluorescein pooling or stain- related medical problems. The ease central scotoma immediately in her

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©2004 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/02/2021 right eye. Three weeks later, a reti- perature rises for small-spot, 10- pensive lens that collimates its di- nal evaluation revealed central fo- second laser pointer and large-spot, ode laser’s divergent, astigmatic veal pigment mottling with corre- 60-second transpupillary thermo- beam. Assuming that a laser pointer sponding faint hyperfluorescence on therapy exposures are compa- beam has a full 5-mW output and a fluorescein angiography. These find- rable.11,24,62 Thus, the most likely standard beam divergence of 1.5 mil- ings became less prominent during mechanism for the documented reti- liradian, only 7% of the laser beam the next 3 months as her scotoma nal damage caused by this laser would enter a 4-mm-diameter pu- resolved, and her uncorrected vi- pointer exposure is threshold transpupil at a distance of 9 m. This expo- sual acuity returned to 20/25 OD, the pillary thermotherapy–type photo- sure would produce a physiologic same as in her unaffected left eye. coagulation. In this case, the an- retinal temperature rise of only She had no other ocular abnormali- swers to all 6 diagnostic questions 0.4°C, which could not cause reti- ties in her right eye. In addition, this given in the Table are “yes,” and this nal injury. Furthermore, at a dis- patient had no recent history of in- episode is a case of laser injury. tance of 9 m from an artificial pu- fection, inflammation, or mechani- pil, a laser pointer can be aimed cal trauma and no contributory past CASE 2 through a 7-mm aperture at best systemic or ocular history. only 25% of the time (B.E.S., D. J. History Lund, BS, H. Zwick, PhD, D. A. Analysis Stamper, MS, P. R. Edsall, BS, J. W. A prankster with a laser pointer mo- Molchany, BS, unpublished data, This 11-year-old girl probably expe- mentarily exposed a middle-aged 1999). Normal head movements and rienced a 5-mW, 10-second, 50-µm worker to the beam of an ordinary hand movements reduce any reti- retinal spot diameter exposure that laser pointer from a distance of 9 m. nal exposure even more, so a laser produced a 6° to 10° retinal tempera- The worker’s visual acuity after the pointer injury from a distance of 9 ture rise with a retinal irradiance of incident was 20/20 OU. In the 4 m is impossible without pupillary di- 160 W/cm2 of diode 635-nm red years after the episode, the worker lation and mechanically restrain- light.5,62 In comparison, clinical pho- developed headaches, progressive ing and aligning both the laser tocoagulation for diabetic retinopa- photophobia, and severe sharp and pointer aperture and the observer’s thy can be performed with a 200- longer-lasting dull eye pains. His pupil for more than 10 seconds. mW, 0.2-second, 200-µm retinal spot photophobia was disabling even We could find only a single ar- diameter exposure that produces a when wearing sunglasses at ordi- ticle66 in the medical literature on 40° to 60° retinal temperature rise nary indoor illumination levels. Vi- photo-oculodynia syndrome, which with a retinal irradiance of 325 W/cm2 sual field tests initially docu- is described as “a category of chronic of argon laser 514-nm green radia- mented unilateral hemianopsia, eye pain triggered by even minor tion.62 Subvisible lesion transpupil- although findings from magnetic ocular trauma, when there is no evi- lary thermotherapy for occult cho- resonance imaging were normal. dence of ongoing tissue damage or roidal neovascularization in age- Fluorescein angiography and eye ex- inflammation.” The term was pro- related macular degeneration can be aminations by numerous ophthal- posed as an alternative to the stan- performed with an 800-mW, 60- mologists immediately after and sub- dard term “photophobia.”66 Only 6 second, 3-mm retinal spot diameter sequent to the episode did not individuals with this condition were exposure that produces a 10° retinal identify organic disease other than described in the article,66 3 of whom temperature rise with a retinal irra- dry eye syndrome. The worker was reported less discomfort after cer- diance of 7.5 W/cm2 of diode laser then seen by a neuro-ophthalmolo- vical sympathetic ganglion block. 810-nm infrared radiation.62 gist, who diagnosed him as having There is no scientific basis for the Laser pointers sold in the United photo-oculodynia syndrome66 and neuro-ophthalmologist’s specula- States are required to have an output attributed the origin of his pain, pho- tion that a complex ocular pain syn- power less than 5 mW.1,2,5,63 Acciden- tophobia, and headaches to previ- drome could be induced by brief, tal momentary laser pointer expo- ous laser pointer exposure. The nondamaging light exposure. If that sure is safe because it is terminated in prankster’s foolishness, the neuro- were the case, there would be mil- less than 0.25 second by normal aver- ophthalmologist’s speculation that lions of people with photo-oculo- sion responses to uncomfortably bril- momentary laser pointer exposure dynia syndrome due to flash pho- liant light.1,2,5,64,65 Prolonged view- can cause photo-oculodynia syn- tography and laser eye surgery. In ing of a laser pointer beam for more drome, and the worker’s excellent this case, the answers to diagnostic than 10 seconds is potentially harm- employment record and reported ab- questions 1 and 6 in the Table are ful,1 which is the reason that these de- sence of health or occupational prob- “no,” and this episode is not a case vices have warning labels. Retinal ir- lems before the incident probably in- of laser injury. radiance produced by a laser pointer fluenced the defendant to settle this held close to the eye is high because worker’s damage claims out of court. CASE 3 much of its power enters the eye and is concentrated into a small retinal Analysis History spot. Conversely, heat conduction cools small retinal spots more effec- Laser pointers are poor optical de- A young male soldier viewing the tively than large ones, so retinal tem- vices that contain a simple, inex- exit aperture of a laser rangefinder

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©2004 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/02/2021 that he was holding accidentally ex- est lateral extent. A foveal fleck was headaches, photophobia, blurred vi- posed his right eye to several pow- present in both eyes. Early fluores- sion, and nighttime driving and read- erful Q-switched, 1064-nm laser cein angiogram frames documented ing difficulties. He reported epi- pulses.20 He reported no pain but no- that the flecks had central hypofluo- sodes of monocular diplopia. He also ticed an immediate decrease in vi- rescence with a surrounding zone of reported a constellation of terrible, sion in his right eye. Ophthalmic ex- hyperfluorescence. The hyperfluo- intermittently disabling, periodic, amination 24 hours later revealed rescence faded in later images. and chronic eye and face pains. The vitreous hemorrhage overlying 2 initial retina specialist ascribed all retinal holes in his right fovea. Fluo- Analysis these symptoms to laser injury. He rescein angiography 5 days after the also diagnosed a laser exposure in incident documented 3 prominent The soldier did not undergo a thor- one of the photographer’s compan- chorioretinal lesions with surround- ough retinal examination or retinal ions present at the incident who re- ing hyperfluorescence. Central imaging studies until 9 years after the ported similar symptoms but had macular scarring progressed in his tank observation incident. At that completely normal findings on reti- right eye, and his visual acuity 18 time, ophthalmoscopy and fluores- nal examination and fluorescein an- months after the laser exposure was cein angiography documented pat- giograms. 20/400 OD. tern RPE dystrophy.67-69 We know of A review of the photogra- no scientific evidence to suggest that pher’s voluminous medical history Analysis this problem is caused or acceler- several years after the episode re- ated by light exposure. The tank that vealed dry eye syndrome, map-dot- Military Q-switched laser rangefind- the soldier observed was probably fingerprint corneal dystrophy, tem- ers and target designators are haz- equipped with a Q-switched ruby la- poromandibular joint syndrome, ardous devices with radiation out- ser (694.3-nm, red) rangefinder. Q- iritis, conjunctivitis, migratory ar- puts that far exceed maximum switched retinal laser injuries typi- thritis, plantar fasciitis, chronic low permissible exposure levels.20,44,63 In- cally cause immediate vision loss and back pain, epididymitis, and recur- juries to users and bystanders con- a prominent, permanent chorioreti- rent diarrhea. Most of the systemic tinue to occur infrequently despite nal scar. The soldier did not have vi- problems predated the purported la- careful precautions and safety train- sion loss after the incident or a cho- ser incident. New RPE defects de- ing. In this case, the answers to all rioretinal scar consistent with laser veloped after the incident. The pho- 6 diagnostic questions in the Table injury. Furthermore, the type of ruby tographer had not been diagnosed are “yes,” and this episode is a case laser rangefinder known to be on the previously as having reactive arthri- of laser injury. kind of tank he observed produces tis (Reiter syndrome),71 which can a retinal exposure far below inter- produce small RPE defects.72,73 No CASE 4 national safety standards at a 3-km evidence of laser injury was found viewing distance.63,70 In this case, the in the years after the incident by 17 History answers to questions 1 and 6 in the other ophthalmologists, including 5 Table are “no,” and this episode is neuro-ophthalmologists and 8 retina A 40-year-old male soldier ob- not a case of laser injury. specialists. A trial was held 5 years served 3 red light pulses emitted in after the incident in which the retina 3 seconds by a tank approximately CASE 5 specialist who made the initial di- 3 km from his helicopter. He re- agnosis steadfastly maintained that ported ocular discomfort for ap- History all the photographer’s symptoms proximately an hour after the mis- were due to retinal laser injury. A sion. These symptoms were relieved A middle-aged photographer had jury ruled against the photogra- by acetaminophen use and did not pain from a corneal abrasion after pher’s claim for damages against the recur. His visual acuity was 20/20 taking photographs of a ship. He sur- ship owner. OU after the incident and when mised that there had been a laser de- tested several times during the next vice on the ship and that a laser in- Analysis 5 years. The soldier experienced jury had caused his discomfort. His metamorphopsia 7 years after the visual acuity was 20/20 OU after the No laser was ever identified in this episode. He sought medical care 2 episode. A retina specialist found 3 case despite a search of the ship. A years later, concerned that he might tiny (10- to 20-µm) RPE window de- costly, time-consuming chain of be going blind from a laser expo- fects in one eye on a fluorescein an- events was precipitated by the ini- sure. When examined at that time, giogram and ascribed them to laser tial retina specialist’s (1) failure to his uncorrected visual acuity was injury. Findings from optical coher- attach significance to an associa- 20/20 OD and 20/50 OS, improv- ence tomography were normal. Am- tion between the photographer’s able to 20/20 OS, where his re- sler grid test results were highly vari- symptoms and his complex past sponses were slower. Findings from able, and the locations of grid medical history, (2) quick diagno- anterior segment examination were abnormalities and RPE defects were sis of a laser injury, (3) subsequent normal, but there were numerous inconsistent. attribution of the photographer’s yellow flecks in each macula, ap- During the next 5 years, the growing list of pains and visual com- proximately 50 to 100 µm in long- photographer developed chronic plaints to a laser injury, and (4) di-

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©2004 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/02/2021 agnosis of laser exposure in the pho- dants only when they support their REFERENCES tographer’s associate based on clients’ biases and best interests. symptoms in the absence of retinal Medical “experts” are hired to ad- or angiographic abnormalities. As vocate opinions that are often un- 1. Sliney DH, Dennis JE. Safety concerns about laser pointers. J Laser Appl. 1994;6:159-164. noted previously herein, the few tiny related to evidenced-based medical 2. Mainster MA, Timberlake GT, Warren KA, Sliney RPE defects on which the initial di- practice. Juries struggle to separate DH. Pointers on laser pointers. Ophthalmology. agnosis was based are common. reality from fiction. Attorneys may 1997;104:1213-1214. Even if these defects were due to craft convincing cases for “victims” 3. Rockwell RJ Jr, Ertle WJ, Moss CE. Safety rec- ommendation for laser pointers. 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New York, NY: Springer-Verlag NY Inc; 1993. diagnosis is proportional to the se- or months to complete authorita- 14. Mainster MA. Finding your way in the photofor- verity of the injury. In ambiguous tively. Hasty diagnoses should be est: laser effects for clinicians. Ophthalmology. cases, subtle retinal findings should avoided because they can create se- 1984;91:886-888. have excellent visual prognoses and rious and lengthy medical, legal, and 15. Marshall J. Structural aspects of laser-induced damage and their functional implications. Health clinical outcomes. Absence of a reti- social issues. The 6 key diagnostic Phys. 1989;56:617-624. nal lesion does not prove absence of questions given in the Table pro- 16. Glickman RD. Phototoxicity to the retina: mecha- laser exposure. Nonetheless, reti- vide a framework for evaluating po- nisms of damage. Int J Toxicol. 2002;21:473-490. nal laser lesions that cause serious tential laser injuries. The diagnosis 17. 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