Ocular air-gun injury: 19 cases

A series of 777 pellet gun ocular injuries over a 4-month period in Kashmir

Purpose

To examine the incidence, clinical findings and management of pellet gun-related ocular injuries that occurred during protests in Kashmir region.

Methods

This retrospective study included records from 777 patients diagnosed with pellet gun-related ocular injuries admitted to a tertiary hospital in Srinagar, India, between July and November 2016. By reviewing the clinical records, the following data were collected: demographics, clinical information pertaining to the injury, imaging reports including computer tomography and ultrasonography B-scan, management in the emergency setting, and follow-up treatment.

Results

Mean age was 22.3 ± 7.2 years and majority patients were male (97.7%). In terms of laterality, 94.3% and 5.7% of the patients sustained monocular and binocular injuries, respectively. In terms of the nature of injury, 76.3% of the eyes had open globe injury while 23.7% of the eyes had closed eye injury. Emergency surgical exploration was performed in 67.7% of closed globe injuries while emergency primary repair was done in 91.1% of open globe injuries. The vast majority of patients (98.7%) who required surgery underwent surgical intervention on the day of admission or the next day. Final best-corrected visual acuity (BCVA) after treatment was counting fingers or worse in 82.4% of the eyes.

Conclusion

Pellet gun-related ocular injuries resulted in significant ocular morbidity, mostly manifesting as open globe injuries. Treatment often required surgical interventions, but despite expeditious management, visual prognosis remained poor for most of the patients.

Pathomimia in a practice of an ophthalmologist

Non-suicidal self-inflicted injuries are encountered in the practice of doctors of all specialties. Within the framework of this article, a case of surgical treatment of a female patient with pathomimia and lagophthalmos will be presented.

Finite Element Analysis of Changes in Tensile Strain by Airsoft Gun Impact on Eye and Deformation Rate in Eyes of Various Axial Lengths

Purpose

We have carried out three-dimensional finite element analysis (FEA) to determine the physical and mechanical response in several ocular injuries. We applied this FEA model to evaluate an airsoft gun impact on an eye and the deformation rate of eyes of various axial lengths at various velocities.

Methods

This study was carried out on a human eye model using an FEA program created by Nihon, ESI Group. The airsoft gun pellet was set to impact the eye at initial velocities of 45, 60 and 75 m/s with the addition of variation in axial length of 20 mm (hyperopia), 22 mm (emmetropia), 24 mm (myopia) and 26 mm (high myopia). Deformation of the eye was calculated as the decrease rate of the volume of the eyeball and the decrease rate of the axial length.

Results

In all emmetropic cases, the cornea reached its strain threshold during the impact, and scleral strain showed a patchy strength distribution in the simulation. The deformation was most evident in the anterior segment, while deformation of the posterior segment was less. The decrease rate of the volume of the eyeball and decrease rate of the axial length were highest in the hyperopic eye, followed by the emmetropic eye and myopic eye, and the high myopic eye showed the lowest decrease rates among the four axial lengths in all impact velocity simulations.

Conclusion

These results suggest that hyperopic eyes are most susceptible to deformation by an airsoft gun impact compared with other axial length eye models in this simulation. The considerable deformation by an airsoft gun impact shown in this study might indicate the necessity of ocular protection to avoid permanent eye injury. FEA using a human eyeball model might be a useful method to analyze and predict the mechanical features of ocular injury by an airsoft gun.

Finite Element Analysis of Air Gun Impact on Post-Keratoplasty Eye

Purpose

Due to the mechanical vulnerability of eyes that have undergone penetrating keratoplasty (PKP), it is clinically important to evaluate the possibility of corneal wound dehiscence by blunt impact. We have previously developed a simulation model resembling a human eye based on information obtained from cadaver eyes and applied three-dimensional finite element analysis (FEA) to determine the physical and mechanical response to an air gun impact at various velocities on the post-PKP eye.

Methods

Simulations in a human eye model were performed with a computer using a FEA program created by Nihon, ESI Group. The air gun pellet was set to impact the eye at three-different velocities in straight or 12° up-gaze positions with the addition of variation in keratoplasty suture strength of 30%, 50% and 100% of normal corneal strength.

Results

Furthermore to little damage in the case of 100% strength, in cases of lower strength in a straight-gaze position, wound rupture seemed to occur in the early phase (0.04-0.06 ms) of impact at low velocities, while regional break was observed at 0.14 ms after an impact at high velocity (75 m/s). In contrast, wound damage was observed in the lower quadrant of the suture zone and sclera in 12° up-gaze cases. Wound damage was observed 0.08 ms after an impact threatening corneoscleral laceration, and the involved area being larger in middle impact velocity (60 m/s) simulations than in lower impact velocity simulations, and larger damaged area was observed in high impact velocity cases and leading to corneoscleral laceration.

Conclusion

These results suggest that the eye is most susceptible to corneal damage around the suture area especially with a straight-gaze impact by an air gun, and that special precautionary measures should be considered in patients who undergo PKP. FEA using a human eyeball model might be a useful method to analyze and predict the mechanical features of eyes that undergo keratoplasty.

Gun-related eye injuries: A primer

Gun-related eye injuries are relatively common in the context of gunshot wounds to the head and neck. Many of the fundamental principles of gunshot wound management apply to the care of these patients, but the complex anatomy and functional relationships of the periocular region do pose special challenges. We provide a focused primer for physicians seeking a more in-depth understanding of gun-related eye injuries and present 3 representative cases outlining the spectrum of pathology, provide a focused review of the relevant ballistics concepts, and discuss the management of injuries to the periocular soft tissues, orbital structures, and globe. We found that good cosmetic and functional results can often be achieved with appropriate early intervention, but visual prognosis may remain guarded despite optimal treatment.

Airsoft gun-related ocular injuries: long-term follow-up

PURPOSE

To describe the long-term ocular effects of airsoft gun pellet injuries.

METHODS

The present study extends by 7-10 years the results of a 2010 study on the acute ocular findings related to airsoft gun pellet injuries in 59 patients, wherein we found a variety of anterior and posterior segment injuries, including hyphema (66%), corneal edema (61%), corneal erosions (59%), and traumatic mydriasis (25%), as well as retinal edema in (22%), retinal hemorrhages and mild vitreous hemorrhage in (2.1%), and, in 1 patient, elevated intraocular pressure and traumatic cataract.

RESULTS

Of the 59 patients in the original study, up-to-date medical records were available for 26 (44%; 20 males). The mean follow-up time was 8 years (range, 7.2-10.3 years); the mean age, 17.1 years. Persistent abnormal findings included traumatic cataract in 3 cases (11.5%) and iris dialysis in 1 case (3.8%). In all traumatic cataract cases, cataract was not present at the time of initial examination after injury. Final mean best-corrected visual acuity was 0.92 (range 0.67-1.0), logMAR 0.03 (range 0.18-0).

CONCLUSIONS

While most acute airsoft gun-related ocular injuries are transient, some patients may develop significant and potentially sight-threatening ocular damage, even in the absence of significant pathologic findings at the time of the injury. Long-term follow-up on these patients is advisable.

Pellet gun injury as a source of ocular trauma; a retrospective review of one hundred and eleven cases

Purpose

To report the demographic data, treatment methods, and outcomes among patients with pellet gun eye injuries.

Methods

This study was a retrospective review of all pellet gun eye injuries coming to Farabi Eye Hospital, a referral ocular trauma center in Iran, from February 2009 to November 2013. Patients' demographics, type of injury, choice of management, complications, and post-treatment visual acuity were recorded.

Results

One hundred eleven patients with a mean age of 25.7 ± 15.6 years entered the study. The most common age group was younger adults (16–45 years old) (61.3%). The mean uncorrected visual acuity after treatment was 2.05 (20/2240) ±1.5 logMAR. The most prevalent ocular zone was zone III (38.7%), and an intraocular foreign body was present in 97 patients (87.4%). Lid laceration and periocular tissue damage were present in 27 patients (24.3%). Lensectomy and vitrectomy were the most common treatment (31.5%). In most patients (87.4%), the injury was non-deliberate, and the most common time of hospitalization was the same day (45.0%). The only statistically significant indicator of post-treatment visual acuity was ocular trauma score (OTS) at admission (P < 0.001). At the end of follow-up, enucleation was performed for 20 patients (18%), and thirty-six patients (32%) had no light perception (NLP) in vision.

Conclusion

Pellet gun injuries were more common among young male patients, and the only statistically significant indicator of post-treatment visual acuity was OTS at admission.

Auditory risk of air rifles

OBJECTIVE

To characterize the impulse noise exposure and auditory risk for air rifle users for both youth and adults.

DESIGN

Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit and LAeq75 exposure limit suggested by the World Health Organization (1999) for children.

STUDY SAMPLE

Impulses were generated by nine pellet air rifles and one BB air rifle.

RESULTS

None of the air rifles generated peak levels that exceeded the 140 dB peak limit for adults, and eight (80%) exceeded the 120 dB peak SPL limit for youth. In general, for both adults and youth, there is minimal auditory risk when shooting fewer than 100 unprotected shots with pellet air rifles. Air rifles with suppressors were less hazardous than those without suppressors, and the pellet air rifles with higher velocities were generally more hazardous than those with lower velocities.

CONCLUSION

To minimize auditory risk, youth should utilize air rifles with an integrated suppressor and lower velocity ratings. Air rifle shooters are advised to wear hearing protection whenever engaging in shooting activities in order to gain self-efficacy and model appropriate hearing health behaviors necessary for recreational firearm use.

Airgun shot wound to the orbit with retention of pellet. Case report and review of the literature

Shot wounds become a growing clinical concern in the civilian setting, due to increasing popularity of air guns among minors. We present a pediatric case of a shot wound to the orbit with sparing of the eyeball and retention of airgun pellet in the retrobulbar space. The pellet was removed 3 months after injury via lateral orbitotomy. Pathophysiology and ballistics of shot wounds are briefly reviewed and current views on the management strategy of shot wounds with retained projectile are discussed.

The early management of gunshot wounds Part II: the abdomen, extremities and special situations

The management of gunshot wounds of the abdomen and extremities is evolving with centres who treat large volumes of such injuries tending to the application of a policy of selective non-operative management. This article discusses the management of gunshot wounds to the abdomen and extremities and reviews the evidence supporting these changing practices. Special situations such as wounding by shotguns or air rifles are also examined as are the special considerations needed when dealing with the gunshot injured pregnant women or in a child.

The epidemiology and etiology of pediatric ocular trauma

Eighteen million people worldwide have uniocular blindness from traumatic injury. Injuries occur disproportionally commonly in childhood. Every year a quarter of a million children present with serious ocular trauma. For the vast majority the injury is preventable. We review the international literature that identifies high-risk circumstances.

Airsoft gun-related ocular injuries: novel findings, ballistics investigation, and histopathologic study

PURPOSE

To describe the ocular injuries related to airsoft gun bullets, investigate the ballistics of airsoft bullets, record real-time impact of the bullets on an eye, and investigate the histopathologic changes within the cornea after being hit by an airsoft gun bullet.

DESIGN

Retrospective, interventional case series and experimental animal study.

METHODS

All consecutive cases of patients with airsoft gun-related ocular injuries during 2006 to 2008 were included in this study. Porcine eyes were used for high-speed video photographs of bullet impacts. Rabbit eyes were used for the histopathologic investigation. All patients were treated in the Department of Ophthalmology at Soroka University Medical Center, Beer-Sheva, Israel. Laboratory investigations were performed at Ben-Gurion University of the Negev, Beer-Sheva, Israel. The main outcome measures were ocular injuries of the patients, ballistics of the airsoft bullets, nature of corneal deformation upon impact, and corneal histopathologic changes after the hit.

RESULTS

Fifty-nine patients with a mean age of 9.8 +/- 3.8 years (range, 2.8 to 26 years) were examined; 49 were male (83.1%). The ocular injuries included hyphema, corneal edema, corneal erosion, traumatic mydriasis, and posterior segment involvement. A novel, "donut" form of corneal erosion was seen and also demonstrated by the histopathologic investigation. Substantial anterior segment deformation was recorded in real-time using the high-speed video camera.

CONCLUSIONS

Airsoft gun injuries affect mainly young men and can be visually threatening. Typical ocular injuries along with a unique form of corneal erosion can be seen.

Ocular air gun injuries: a one-year surveillance study in the UK and Eire (BOSU). 2001-2002

AIMS

The vulnerability of the eye means that ocular air gun injuries figure prominently in the medical literature. This Study reports the results of the first ocular air gun injury surveillance study.

METHODS

Ocular air gun injuries were reported to the British Ophthalmic Surveillance Unit (BOSU; United Kingdom and Eire) for the period November 2001-December 2002 (13 months). Two questionnaires were used to collect demographic details, circumstances of injury, details of injuries, medical management and outcome.

RESULTS

A total of 105 initial and 99 follow-up questionnaires were returned. Eighty-six ocular air gun injuries occurred during the last 12 months of surveillance yielding a corrected, estimated incidence of 91-115 injuries/year. Injuries were most frequent in August/September, and 90% (95/105) of victims were men with mean age of 17.5 years (74% under 18 years). In all, 40% (32/81) of injuries occurred at home and 53% (43/81) in a public place. 23% (19/84) of injuries were deliberate, 66% (69/104) of injuries were severe and 20% (21/105) resulted in ruptured globes. In all, 54% (48/89) required hospital admission and 41 required surgery. A total of 11% (12/105) of eyes were either enucleated or eviscerated. Final visual acuity was <or=counting fingers in 29% (26/91) but >6/12 (Snellen) in 65% (59/91). Moderate/significant cosmetic deformities were recorded in 10% (8/77) and restricted ocular movements in 5% (4/72).

CONCLUSIONS

Ocular air gun injuries damage sight and leave lasting morbidity. The demographics and circumstances of injury are well documented with access to, and unsupervised use of, air guns, appearing the principal risks for injury.

33 cases of airsoft gun pellet ocular injuries in Copenhagen, Denmark, 1998-2002

PURPOSE

To evaluate the incidence and ocular effects of blunt trauma due to injury from airsoft gun pellets.

METHODS

We conducted a non-comparative case series based on the files of 33 patients who suffered ocular injury from airsoft guns and were admitted to one university emergency eye clinic in Copenhagen during a 5-year period.

RESULTS

A total of 33 eyes in 33 patients were examined. Thirty male and three female patients were affected. Mean age was 13 years (range 3-49 years). Mean follow-up time was 6.5 days (range 1-540 days). On initial examination, we found: hyphaema (n = 28), corneal abrasion (n = 22), retinal oedema (n = 11), subconjunctival haemorrhage (n = 10), palpebral haemorrhage and/or oedema (n = 9), iris dialysis (n = 7), intraocular pressure (IOP) > 31 mmHg (n = 4), IOP < 9 mmHg (n = 4), vitreous haemorrhage (n = 2) and cataract (n = 1). One patient had brown corneal discoloration due to severe chronic hyphaema that required surgery. The final visual acuity was 1.0 in 20 patients and < or = 0.7 in five patients.

CONCLUSION

The airsoft gun trauma resulted in anterior and posterior segment ocular injuries that required acute medical intervention and for which some patients were hospitalized. Trauma mainly occurred in children and youths. A longterm risk of glaucoma is expected. Eye care professionals and parents as well as manufacturers of airsoft guns should advise participants to wear adequate protection when involved in this activity.

Self-inflicted eye injuries: a review

PURPOSE

To review the pathogenesis, clinical characteristics, and management of self-inflicted eye injuries.

METHODS

Review of the medical literature.

RESULTS

Psychiatric theories of pathogenesis for self-inflicted behaviour include religious and sexual ideation, symbolism, guilt, and displacement. Biological theories include disorders of serotonergic, dopaminergic, and opiate neurotransmitters. Clinical characteristics of self-mutilators include acute or chronic psychoses, drug-induced psychoses, other psychiatric conditions, and certain organic states. The majority are young-to-early middle-aged male subjects, though it can also rarely occur in children. Management of self-inflicted eye injury requires close cooperation between ophthalmologists and psychiatrists as well as other medical specialists, to ensure quick resuscitation of the patient, prompt diagnosis and treatment of any injuries, and treatment of the underlying behaviour that led to the injuries.

CONCLUSIONS

Self-inflicted eye injuries are a rare but important group of ophthalmic conditions that require close cooperation between different medical specialties to ensure optimum care of the often severely disturbed patient.

Trans-orbital intra-cranial air gun injury

PURPOSE

To describe a case of trans-orbital intra-cranial air gun injury with a discussion on air gun related morbidity and mortality.

METHODS

Case report and literature review.

RESULTS

The air gun pellet travelled through the orbit without penetrating the globe. It passed into the middle cranial fossa through the superior orbital fissure and lodged in the temporal lobe. The patient was managed conservatively with antibiotics and antiepilectis.

CONCLUSIONS

Air gun design has changed in recent years resulting in an increased morbidity and mortality. Stricter legislation on the sale and use of these weapons needs to be implemented.