Simultaneous Bilateral Ocular Trauma: Clinical Presentation, Epidemiology and Patterns of Injury

Purpose This study aimed to determine the frequency, sociodemographic prole, clinical presentation, patterns of injury, treatment and outcomes of cases of simultaneous bilateral ocular trauma. Methods This retrospective study conducted from to The medical records of patients presenting with bilateral We found that major causes of simultaneous bilateral ocular trauma were assaults (including physical assault, acid attacks and gunshots injury) and sports or recreational activities (including cracker burn). Most of the victims had polytrauma and a multidisciplinary approach was required for management. Based on our ndings, it is recommended to use ocular protective measures during potentially dangerous activities, needs of modication of violent behavior and to resolve the conicts as early as possible.


Introduction
Ocular trauma is the leading cause of avoidable acquired blindness worldwide, with an estimated 55 million ocular injuries occurring annually, of which 19 million result in severe visual loss and blindness. [1] Worldwide, approximately 1.6 million people suffer from blindness arising from ocular injury and 2.3 million have bilateral visual impairment due to trauma. [2] While ocular trauma is a signi cant cause of monocular blindness, the simultaneous involvement of both eyes is rare. Bilateral ocular trauma is often associated with serious physical disability, dis gurement and visual loss, with the reported prevalence of bilateral blindness due to trauma ranging from 3.2-5.5%. [3] Road tra c injuries (RTIs), physical assault and blast injuries are frequent causes of severe bilateral ocular injuries. [4][5][6] Ocular trauma can have a signi cant psychological and socioeconomic impact on the affected individual, their family and society at large. [7] Moreover, the treatment of severe bilateral ocular trauma is often di cult and challenging, thereby requiring strategic management. As a result, it is important to identify the epidemiology and risk factors of this type of trauma. The objective of this study was therefore to determine the frequency, sociodemographic pro le, clinical presentation, patterns of injury, treatment and outcome of cases of simultaneous bilateral ocular trauma.

Methods
This retrospective study involved all patients with simultaneous bilateral ocular trauma who were diagnosed and managed between May 2015andApril 2019at the Sir Sunderlal Hospital, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India. The study was approved by the institutional ethical committee of Banaras Hindu University. All study procedures adhered to the recommendations of the revised Declaration of Helsinki. Patient privacy and con dentiality was maintained using a data abstraction form.
A review of the patients' hospital records and investigation reports was conducted to collect information regarding the patients' demographic pro le (i.e. age, gender, place of residence and socioeconomic status), injury pro le (i.e. time, place, session, circumstances and cause of injury and type of traumatic agent), clinical pro le (i.e. type, location, zone, severity and depth of injury, initial visual acuity, ocular trauma score [OTS] and associated injuries) and outcome (i.e. management modality, time to presentation, nal visual acuity and determinants for impaired vision or blindness).
Collected data were analysed using the Statistical Package for the Social Sciences (SPSS) software, version 15 (IBM Corp., Armonk, NY, USA). A student's two-tailed t-test was used to compare quantitative variables while a Chi-squared test was used to compare categorical variables. The level of statistical signi cance was set at p < 0.05.

Injury pro le
The majority of patients were injured in the afternoon (50.00%), followed by the morning (23.53%) and the evening (20.59%). The remaining two cases (5.88%) were elderly patients who were injured after falling from the roof late at night. Most injuries occurred in summer (50.00%) or during the rainy season (35.29%), with few cases occurring in winter (14.71%). The most common place of injury was away from home (64.71%), including in roads (32.36%), in playgrounds/at school (14.71%) and in the workplace (11.76%). Non-occupational trauma was most common (91.18%), including assault-related trauma (26.47%), rail related injury or RTI (20.59%), sports or recreational activities (17.65%) and domestic accidents (14.71%).
In the majority of cases, the traumatic agent was solid in form (41.18%), followed by particulate matter (20.59%), uid/gel (14.71%) and of indeterminate form (23.53%). The most common mode of injury was collision or impact (41.18%), followed by blasts or gunshots (20.59%), projectile objects (11.76%) and falling (11.76%). Three patients (8.82%) were injured due to animal bites. The majority of victims (82.35%) were not using protective devices at the time of injury and 38.24% had consumed alcohol. Table 2 shows the detailed injury pro le of the sample.  Table 3 summarises the injury patterns observed in the sample.

Discussion
Ocular trauma is an under-recognised and under-reported cause of vision loss; moreover, while bilateral ocular trauma is comparatively uncommon, it can lead to severe visual impairment and long-term disability. [2,3,7] Unfortunately, little information is currently available regarding the magnitude, epidemiology and injury patterns of this condition. To our best knowledge, this is the third study to report clinical and epidemiological data regarding cases of simultaneous bilateral ocular trauma. These ndings provide insight into the epidemiology, clinical characteristics and outcomes of cases of simultaneous ocular injuries presenting to the largest tertiary referral hospital in Eastern Uttar Pradesh, India.
The incidence of bilateral ocular injuries depends on a wide variety of factors, including geographical location, climate, culture, social values, common occupations, rates of crime and violence and common types of trauma and traumatic agents. In our study, simultaneous bilateral injuries occurred in 8.46% of patients presenting with ocular trauma over a six-year period. Sabaci et al. reported bilateral involvement in 16 (7.55%) of 212 patients with weapon-related OGIs. [8] In a previous study carried out at the Sir Sunderlal Hospital, 22.9% of university students with ocular injuries were affected in both eyes, with ocular injuries most commonly attributed to assault, RTAs and recreational activities. [4] In contrast, other studies have reported lower rates of bilateral ocular injuries(0.69-3.0%). [5,9,10] In contrast, according to an interview-based survey in Nepal, the prevalence of trauma-related bilateral blindness was 20%. [7] There was a male predominance in the current study, with the male-to-female ratio being 2.4:1. This nding is comparable to that reported in other studies [6,10]. Moreover, young adults (i.e. 16-25 and 26-35 years old) and older children and adolescents (i.e. 6-15 years old) represented the most vulnerable age groups. In general, young men tend to spend more time outdoors, are often employed in occupations involving manual labour and are more likely to be involved in violence or risky behaviours, factors which place them at greater risk of injury and trauma. [11,12] In this study, the majority of patients resided in rural areas, demonstrated poor literacy and were of low socioeconomic status; furthermore, such patients were more likely to have poor outcomes due to a lack of eye protection and delays in seeking medical care. These individuals should therefore be considered a high-risk group in terms of prognosis.
The majority of bilateral ocular injuries in our study occurred during summer and the rainy season; similar results have been reported by other researchers. [13,14] In contrast, Canavan et al. reported that ocular injuries in Ireland usually transpired during the winter season as a result of the increased prevalence of dangerous sporting activities and domestic accidents. [15] Several reasons are proposed for the high incidence of injury in summer and low incidence in the winter season noted in the present study. Many college and university students engage in outdoor games and activities during their summer holidays, potentially making them more injury prone. Secondly, summer is culturally considered marriage season in India and people are therefore often exposed to reworks and travel-related injuries. Finally, the cold, foggy climate and the occurrence of annual college examinations in the winter season would limit involvement in outdoor activities.
In this study, most patients were injured in the afternoon between 12:00 and17.59 hours (50.00%); this is to be expected given that this interval represents the peak time for outdoor activities. In addition, the most common place of injury was away from home (64.71%), including in the street, at school/college and in the playground. This is consistent with results reported in other studies. [5,8,9,16] In comparison, the commonest place for monocular injuries is reportedly at home, particularly among children and women. [17][18][19][20][21]. However, Tok et al. reported that paediatric ocular injuries were less prevalent at home compared to elsewhere [22].
In our study, mechanical injuries (47.05%) accounted for the majority of simultaneous bilateral ocular injuries, with most cases being non-occupational in nature (91.18%). The most common cause of injury was assault (26.47%), including physical assault, acid attacks and gunshots. Similar incidence rates of assault-related ocular trauma have been previously reported (22-30%). [5,23,24] However, other researchers have reported much higher incidence rates of assault-related ocular injury (34-53%). [17,25,26] Other common causes of ocular injuries in the present study included RTIs (20.59%), Traumatic agents in the present study were mostly solid in nature (41.18%), with the most common mode of injury being collision/impact (41.18%), followed by blast/gunshots (20.59%). Over one-third of the victims (38.24%) were under the in uence of alcohol at the time of injury. Moreover, 82.35% were not using a protective device, a major risk factor for severe ocular injury. When analysing the period of time elapsed between injury and seeking medical care, the majority of the patients presented one day after injury (41.17%). Of the 14.71% of victims who reported to hospital several days after the traumatic incident, the majority came from rural backgrounds and were of low socioeconomic status. Previous studies have indicated that delayed hospital presentation is a major risk factor for poor visual outcomes in patients with serious ocular injuries. [28,29] The majority of our patients had polytrauma (58.82%),while 41.18% had isolated ocular trauma, thus indicating that the management of bilateral ocular trauma requires a multidisciplinary approach. In particular, assault, RTIs and falls were common causes of polytrauma; similar ndings have been reported previously [25,30]. In our study, the most common ocular structure involved was the periocular tissues and eyelid (63.24%), followed by the globe (44.12% OGIs with wound sizes of > 10 mm. [29] Our results demonstrated that zone III OGIs, poor initial visual acuity, the presence of associated intraocular haemorrhage (i.e. hyphaema and vitreous haemorrhage), injury to the lens or uveal tissue, retinal detachment and low OTS values (categories I or II) were poor prognostic factors. Similar observations have been reported in other studies. [22,[33][34][35][36][37][38][39].
The results of this study should be considered in light of certain limitations. The study was retrospective in nature and not randomised, with data collection limited to the information available in the patients' medical records. Moreover, the sample size was relatively small for the purposes of subgroup comparison. Finally, it is likely that the ndings underestimated the actual incidence of bilateral ocular injuries given that the study was restricted to cases treated at a single teaching hospital in North India.
Nevertheless, this study provides important demographic, clinical and epidemiological information regarding the frequency, presentation and outcomes of cases of simultaneous bilateral ocular trauma.

Conclusion
Simultaneous bilateral ocular trauma is rare. This study highlights the demographic characteristics, injury pro le, risk factors and visual outcomes of simultaneous bilateral ocular trauma cases presenting to a hospital in North India. Major causes of trauma included assault, RTIs, sports/recreational activities and crackers, with the victims being mostly young men. In light of the severe nature and poor outcomes associated with such injuries, the use of ocular protective measures during potentially dangerous activities is recommended.