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Srisombut T, Ittipanichpong P, Arjkongharn N, Tangon D, Kreesang R, Kemchoknatee P. Factors predictive of poor visual outcome in indirect traumatic optic neuropathy: A retrospective cohort study. Injury 2024; 55:111238. [PMID: 38091645 DOI: 10.1016/j.injury.2023.111238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 11/16/2023] [Accepted: 11/24/2023] [Indexed: 01/29/2024]
Abstract
INTRODUCTION The gold standard treatment for indirect traumatic optic neuropathy (ITON) has not yet been conclusively established, and it is essential to gain an understanding of visual prognosis and to counsel patients regarding the predictive risk factors of poor visual outcomes. Currently, there is limited information regarding ITON in Thai populations; therefore, this study aimed to determine the risk factors of poor visual outcome in patients with this condition. METHODS A retrospective review was conducted of all ITON cases diagnosed at Rajavithi Hospital and Sawanpracharak Hospital between January 2016 and December 2022 in order to determine clinical characteristics and evaluate associated risk factors of poor visual prognosis using binary logistic regression analysis. RESULTS The mean age of this cohort of 101 patients was 36.17 years, with a male predominance of 73.3 %. Motor vehicle accidents were the most common cause of ITON, with a statistically significant 79.2 % of cases. The patients were categorized into an "improved group" of 29 patients and an "unimproved group" of 72. The unimproved group had a significantly older mean age and poorer initial visual acuity of 20/200 (p-values 0.001 and p < 0.001 respectively). There was no significant difference between Computed Tomography (CT) findings in the two groups. The improved group had significantly better visual acuity (VA) at 1-month and final follow-up visit than the unimproved group (both p < 0.001). Differences between gender, Glasgow coma score, associated underlying diseases, and duration from trauma to intravenous glucocorticoids therapy in the two groups were not statistically significant. Multivariable logistic regression analysis identified patient age of 40 years or more (Odds ratio (OR) 3.447, 95 % CI, 1.085-10.955, p = 0.036) and poor baseline VA (OR 6.628, 95 % Confidence Interval (CI), 2.308-19.036, p < 0.001) as significant risk factors for poor visual outcome in ITON patients. CONCLUSIONS No clear benefit was found of intravenous glucocorticoids in treatment of ITON. Patients aged 40 years or more and/or with poor baseline visual status should be advised that they are at increased risk of poor final visual outcomes.
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Affiliation(s)
- Thansit Srisombut
- Department of Surgery, Sawanpracharak Hospital, 3 Attakavee, Pak Nam Pho, Mueang Nakhon Sawan, Nakhon Sawan, 60000, Thailand
| | - Paradee Ittipanichpong
- Department of Ophthalmology, Sawanpracharak Hospital, 3 Attakavee, Pak Nam Pho, Mueang Nakhon Sawan, Nakhon Sawan, 60000, Thailand
| | - Niracha Arjkongharn
- Department of Ophthalmology, Rangsit University, Rajavithi Hospital, 2, Phaya Thai Rd, Thung Phaya Thai, Ratchathewi, 10400, Thailand
| | - Duanghathai Tangon
- Faculty of Medicine, Rangsit University, Rajavithi Hospital, 2, Phaya Thai Rd, Thung Phaya Thai, Ratchathewi, Bangkok, 10400, Thailand
| | - Rinrada Kreesang
- Department of Surgery, Sawanpracharak Hospital, 3 Attakavee, Pak Nam Pho, Mueang Nakhon Sawan, Nakhon Sawan, 60000, Thailand
| | - Parinee Kemchoknatee
- Department of Ophthalmology, Rangsit University, Rajavithi Hospital, 2, Phaya Thai Rd, Thung Phaya Thai, Ratchathewi, 10400, Thailand.
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Suh A, Lam M, Shokrollahi Y, Dong P, Gu L, Suh D. Quantifying the efficacy of protective eyewear in pediatric soccer-induced retinal injury. J AAPOS 2023; 27:131.e1-131.e6. [PMID: 37187408 DOI: 10.1016/j.jaapos.2023.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 02/09/2023] [Accepted: 02/20/2023] [Indexed: 05/17/2023]
Abstract
BACKGROUND Ocular injury is common in children playing sports. Sports-related eye injuries, if severe enough, can lead to permanent vision impairment. Soccer, the most popular sport in the world, is a sport in which players rarely use protective eyewear. The purpose of this study was to determine how eye injuries are induced by a soccer ball impact and to evaluate whether eye protection influences the effects of impact. METHODS A finite element (FE) computer simulation was used to simulate soccer ball trauma on a model of the eye with and without eye protection. Protective eyewear of different materials (polycarbonate and acrylic) was modeled to investigate the optimal medium for eye protection. Stress and strain experienced by the eyeball was quantified by the FE computer simulation in each model. RESULTS Protective eyewear was found to be effective in lowering ocular stress and strain by absorbing and redirecting energy from the ball. Compared to the unprotected eye model, polycarbonate eyewear reduced the average stress the retina experienced by 61%, whereas the acrylic model reduced the average stress by 40%. Polycarbonate and acrylic eyewear also reduced the maximum strain experienced by the retina by 69% and 47%, respectively, reducing the severity of deformations of the eye on impact. CONCLUSIONS These findings suggest that wearing protective eyewear, especially when made of polycarbonate, can be an effective means of reducing injury-inducing retinal stress. The use of eye protection is thus recommended for pediatric patients participating in soccer.
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Affiliation(s)
- Andrew Suh
- Tulane University, New Orleans, Louisiana
| | - Matthew Lam
- Creighton University School of Medicine, Omaha, Nebraska
| | - Yasin Shokrollahi
- Department of Biomedical and Mechanical Engineering, Florida Institute of Technology, Melbourne, Florida
| | - Pengfei Dong
- Department of Biomedical and Mechanical Engineering, Florida Institute of Technology, Melbourne, Florida
| | - Linxia Gu
- Department of Biomedical and Mechanical Engineering, Florida Institute of Technology, Melbourne, Florida
| | - Donny Suh
- Gavin Herbert Eye Institute, University of California Irvine, Department of Ophthalmology and Visual Sciences, Irvine, California.
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Ma H, Gao Y, Li JM, Bao YK, Nie C, Yin P, Lyu X, Ding XY, Lu R. Analysis of retinal vasculature changes in indirect traumatic optic neuropathy using optic coherence tomography angiography. Int J Ophthalmol 2022; 15:1344-1351. [PMID: 36017033 DOI: 10.18240/ijo.2022.08.18] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 08/20/2021] [Indexed: 11/23/2022] Open
Abstract
AIM To assess the retinal vasculature alterations in indirect traumatic optic neuropathy (ITON) patients following craniofacial trauma by optic coherence tomography angiography (OCTA). METHODS Patients diagnosed of monocular ITON were recruited from August 2016 to May 2020. OCTA was performed using the AngioVue OCT-A system for two cube scans centered at the optic nerve head and fovea. OCTA data included thicknesses of peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC), as well as proportion of capillary perfusion and data were analyzed for correlation with post-injury timepoints: within 7, 8-30, 31-90, and 91-365d. RESULTS A total of 73 ITON patients were studied. Significant thinning of RNFL and GCC layers and attenuation of microvascular perfusion were observed in ITON eyes as compared to contralateral unaffected eyes (for most of the analyzed sectors and quadrants, P<0.05). Without respect to surgical intervention and vision recovery, the decrease in retinal layer thicknesses and microvascular perfusion was time-dependent, and most significant within three months (P<0.001). CONCLUSION ITON presents with time-dependent thinning of retinal layers and attenuation of microvasculature, indicating possible degeneration of retinal ganglion cells due to reduced retinal blood supply.
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Affiliation(s)
- Huan Ma
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Yang Gao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Jin-Miao Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Yue-Kun Bao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Cong Nie
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Pan Yin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Xi Lyu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Xiao-Yan Ding
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Rong Lu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
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Shokrollahi Y, Dong P, Kaya M, Suh DW, Gu L. Rapid Prediction of Retina Stress and Strain Patterns in Soccer-Related Ocular Injury: Integrating Finite Element Analysis with Machine Learning Approach. Diagnostics (Basel) 2022; 12:1530. [PMID: 35885436 PMCID: PMC9319813 DOI: 10.3390/diagnostics12071530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 06/15/2022] [Accepted: 06/20/2022] [Indexed: 11/16/2022] Open
Abstract
Soccer-related ocular injuries, especially retinal injuries, have attracted increasing attention. The mechanics of a flying soccer ball have induced abnormally higher retinal stresses and strains, and their correlation with retinal injuries has been characterized using the finite element (FE) method. However, FE simulations demand solid mechanical expertise and extensive computational time, both of which are difficult to adopt in clinical settings. This study proposes a framework that combines FE analysis with a machine learning (ML) approach for the fast prediction of retina mechanics. Different impact scenarios were simulated using the FE method to obtain the von Mises stress map and the maximum principal strain map in the posterior retina. These stress and strain patterns, along with their input parameters, were used to train and test a partial least squares regression (PLSR) model to predict the soccer-induced retina stress and strain in terms of distributions and peak magnitudes. The peak von Mises stress and maximum principal strain prediction errors were 3.03% and 9.94% for the frontal impact and were 9.08% and 16.40% for the diagonal impact, respectively. The average prediction error of von Mises stress and the maximum principal strain were 15.62% and 21.15% for frontal impacts and were 10.77% and 21.78% for diagonal impacts, respectively. This work provides a surrogate model of FE analysis for the fast prediction of the dynamic mechanics of the retina in response to the soccer impact, which could be further utilized for developing a diagnostic tool for soccer-related ocular trauma.
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Affiliation(s)
- Yasin Shokrollahi
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA; (Y.S.); (P.D.); (M.K.)
| | - Pengfei Dong
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA; (Y.S.); (P.D.); (M.K.)
| | - Mehmet Kaya
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA; (Y.S.); (P.D.); (M.K.)
| | - Donny W. Suh
- Gavin Herbert Eye Institute (GHEI), University of California at Irvine, Irvine, CA 92697, USA;
| | - Linxia Gu
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA; (Y.S.); (P.D.); (M.K.)
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Ocular biomechanics during improvised explosive device blast: A computational study using eye-specific models. Injury 2022; 53:1401-1415. [PMID: 35144807 PMCID: PMC8940691 DOI: 10.1016/j.injury.2022.02.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/27/2022] [Accepted: 02/03/2022] [Indexed: 02/02/2023]
Abstract
BACKGROUND Eye injuries comprise 10-13% of civilian improvised explosive device (IED) injuries. The bomb blast wave induces a normal and shear forces on the tissues, causing a large acute IOP elevation. This study calculated the biomechanical stresses and strains in the eye due to IED explosion via eye-specific fluid-structure interaction (FSI) models. METHODS Blast occurred at 2, 3, and 4 m from the front and side of the victim and the weights of the IED were 1 and 2 kg. The ground was covered with the deformable soil to mimic the realistic IED explosion condition and reflect the blast wave. RESULTS The IOP elevation of ∼6,000-48,000 mmHg was observed in the eyes while the highest IOP was occurred with the IED weight and distance of 2 kg and 2 m (front) and the lowest was occurred with the IED weight and distance of 1 kg and 4 m (side). Our findings suggest the importance of the victim location and orientation concerning the blast wave when it comes to ocular injury assessment. IOP elevation of ∼2900 and ∼2700 mmHg were observed in ∼1.6 ms after the blast for the IEDS weight of 2 kg and a victim distance of 2 m in front and side blasts, respectively, in consistence with the literature. Nonetheless, IOPs were considerably higher after ∼1.6 ms due to the merging of the bomb blast wave and its reflection off the ground. CONCLUSIONS The stresses and strains were highest for the frontal blast. Both side and frontal blasts caused higher stresses and strains at the rectus muscle insertions where the sclera is thinnest and prone to rupture. Blast angle has no considerable role in the resultant IOP. Front blast with a heavier IED resulted a higher stresses and deformations in the eye connective tissues compared to the side blast.
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Gao Y, Li J, Ma H, Nie C, Lv X, Lin X, Shi J, Lu R. Endoscopic trans-ethmosphenoid optic canal decompression is an optimal choice to save vision for indirect traumatic optic neuropathy. Acta Ophthalmol 2022; 100:e491-e501. [PMID: 34180149 PMCID: PMC9290745 DOI: 10.1111/aos.14951] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 05/12/2021] [Accepted: 05/31/2021] [Indexed: 11/27/2022]
Abstract
Purpose To evaluate and compare the effectiveness of endoscopic trans‐ethmosphenoid optic canal decompression (ETOCD) and steroid pulse therapy (SPT) for indirect traumatic optic neuropathy (ITON). Design Prospective interventional case series. Methods Total 140 monocular ITON patients from January 2017 to June 2019 were recruited, including 100 patients received ETOCD (56 patients received ETOCD only and 44 patients received ETOCD combined with SPT before surgery), and 40 patients received SPT only. Their visual acuity (VA) and visual evoked potential (VEP) were analysed before and after treatments. Initial VA, lag time, causes of injuries and age were analysed for evaluating prognosis of treatment. Results In contrast with patients received SPT only (15/40 = 38%), the effective rate of patients received ETOCD only and patients received ETOCD combined with SPT were both significantly better (46/56 = 82%, p < 0.001 and 30/44 = 68%, p = 0.005). Whether with SPT before ETOCD or not, after ETOCD, patients with VA improvement showed no significant difference. And 59/76 (77.6%) patients showed improvement within 24 hours. Patients who had residual visions achieved higher effective rate than those with no light perception (56/58 = 97% and 20/42 = 48%; p < 0.001) after ETOCD. For patients with long lag time of 21–90 days, 23/32 (72%) patients presented with vision improvement. Moreover, VEP was significantly improved after ETOCD. No severe complications were observed. Conclusions Endoscopic trans‐ethmosphenoid optic canal decompression (ETOCD) is an effective and safe therapy for ITON, which is more effective than SPT. Even for patients with failure in responding to SPT, the successfully physical decompression is the most effective way to rescue optical nerve from permanent damage.
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Affiliation(s)
- Yang Gao
- State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐Sen University Guangzhou China
| | - Jinmiao Li
- State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐Sen University Guangzhou China
| | - Huan Ma
- State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐Sen University Guangzhou China
| | - Cong Nie
- State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐Sen University Guangzhou China
| | - Xi Lv
- State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐Sen University Guangzhou China
| | - Xiaofeng Lin
- State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐Sen University Guangzhou China
| | - Jianbo Shi
- Otorhinolaryngology Hospital The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
| | - Rong Lu
- State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐Sen University Guangzhou China
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Subramaniam DR, Unnikrishnan G, Sundaramurthy A, Rubio JE, Kote VB, Reifman J. Cerebral Vasculature Influences Blast-Induced Biomechanical Responses of Human Brain Tissue. Front Bioeng Biotechnol 2021; 9:744808. [PMID: 34805106 PMCID: PMC8599150 DOI: 10.3389/fbioe.2021.744808] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/18/2021] [Indexed: 11/13/2022] Open
Abstract
Multiple finite-element (FE) models to predict the biomechanical responses in the human brain resulting from the interaction with blast waves have established the importance of including the brain-surface convolutions, the major cerebral veins, and using non-linear brain-tissue properties to improve model accuracy. We hypothesize that inclusion of a more detailed network of cerebral veins and arteries can further enhance the model-predicted biomechanical responses and help identify correlates of blast-induced brain injury. To more comprehensively capture the biomechanical responses of human brain tissues to blast-wave exposure, we coupled a three-dimensional (3-D) detailed-vasculature human-head FE model, previously validated for blunt impact, with a 3-D shock-tube FE model. Using the coupled model, we computed the biomechanical responses of a human head facing an incoming blast wave for blast overpressures (BOPs) equivalent to 68, 83, and 104 kPa. We validated our FE model, which includes the detailed network of cerebral veins and arteries, the gyri and the sulci, and hyper-viscoelastic brain-tissue properties, by comparing the model-predicted intracranial pressure (ICP) values with previously collected data from shock-tube experiments performed on cadaver heads. In addition, to quantify the influence of including a more comprehensive network of brain vessels, we compared the biomechanical responses of our detailed-vasculature model with those of a reduced-vasculature model and a no-vasculature model for the same blast-loading conditions. For the three BOPs, the predicted ICP values matched well with the experimental results in the frontal lobe, with peak-pressure differences of 4-11% and phase-shift differences of 9-13%. As expected, incorporating the detailed cerebral vasculature did not influence the ICP, however, it redistributed the peak brain-tissue strains by as much as 30% and yielded peak strain differences of up to 7%. When compared to existing reduced-vasculature FE models that only include the major cerebral veins, our high-fidelity model redistributed the brain-tissue strains in most of the brain, highlighting the importance of including a detailed cerebral vessel network in human-head FE models to more comprehensively account for the biomechanical responses induced by blast exposure.
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Affiliation(s)
- Dhananjay Radhakrishnan Subramaniam
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, United States Army Medical Research and Development Command, Fort Detrick, MD, United States
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Ginu Unnikrishnan
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, United States Army Medical Research and Development Command, Fort Detrick, MD, United States
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Aravind Sundaramurthy
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, United States Army Medical Research and Development Command, Fort Detrick, MD, United States
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Jose E. Rubio
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, United States Army Medical Research and Development Command, Fort Detrick, MD, United States
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Vivek Bhaskar Kote
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, United States Army Medical Research and Development Command, Fort Detrick, MD, United States
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Jaques Reifman
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, United States Army Medical Research and Development Command, Fort Detrick, MD, United States
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Karimi A, Razaghi R, Girkin CA, Downs JC. Ocular biomechanics due to ground blast reinforcement. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2021; 211:106425. [PMID: 34598082 PMCID: PMC8577623 DOI: 10.1016/j.cmpb.2021.106425] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 09/14/2021] [Indexed: 05/24/2023]
Abstract
BACKGROUND AND OBJECTIVE Bomb blast injuries exerts a shearing force on the air-tissue interfaces, causing devastating ocular injury from the blast wave. Improvised explosive devices (IEDs) are usually placed at different heights from the ground to induce more severe injury through ground blast reinforcement (GBR). However, there is still a lack of knowledge of the role of GBR and IED height from the ground on ocular biomechanics, and how they can affect the intraocular pressure (IOP) in the eye. This study aimed to estimate the IOP due to frontal IED explosion at different heights from the ground using a fluid-structure interaction model with and without GBR effects. METHODS A 2 kg IED was placed within 5 m of the victim at 5 different heights from the ground, including 0, 0.42, 0.85, 1.27, and 1.70 m. Two different blast formulations were used to simulate the IED explosion: (a) spherical airburst, with no amplification of the initial shock wave due to interaction with the ground-surface, and (b) hemispherical surface-burst, where the initial blast wave is immediately reflected and reinforced by the ground (GBR). RESULTS Results revealed that the blast wave due to GBR reaches to the skull prior to the IED blast itself. The GBR also reached to the skull ∼ 0.6 ms earlier when the IED was on the ground compared to the height of 1.70 m. The highest and lowest IOPs of ∼ 17,000 and ∼ 15,000 mmHg were observed at the IED heights of 1.70 and 0 m from the ground considering GBR. However, when the role of the GBR is ignored, IOP of ∼ 9,000 mmHg was observed regardless of the IED height from the ground. The deformation in the apex of the cornea was higher when considering the GBR (∼ 0.75 cm) versus no GBR (∼ 0.65 cm). Considering GBR led to higher stresses and strains in the sclera. CONCLUSIONS When the role of GBR was ignored, the results showed similar patterns and magnitudes of stresses and deformations in the skull and eye regardless of the height of the IED from the ground, which was not the case when GBR was considered. The findings of this study suggest the critical role of GBR in ocular blast simulations.
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Affiliation(s)
- Alireza Karimi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, 1670 University Boulevard, VH 390A, Birmingham, AL 35294, United States.
| | - Reza Razaghi
- Research Department, Heel of Scene Ltd., 2 Chome-12-3 Honmachi, Shibuya City, Tokyo, Japan.
| | - Christopher A Girkin
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, 1670 University Boulevard, VH 390A, Birmingham, AL 35294, United States.
| | - J Crawford Downs
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, 1670 University Boulevard, VH 390A, Birmingham, AL 35294, United States.
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Hussain SF, Raza Z, Cash ATG, Zampieri T, Mazzoli RA, Kardon RH, Gomes RSM. Traumatic brain injury and sight loss in military and veteran populations- a review. Mil Med Res 2021; 8:42. [PMID: 34315537 PMCID: PMC8317328 DOI: 10.1186/s40779-021-00334-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 06/23/2021] [Indexed: 01/14/2023] Open
Abstract
War and combat exposure pose great risks to the vision system. More recently, vision related deficiencies and impairments have become common with the increased use of powerful explosive devices and the subsequent rise in incidence of traumatic brain injury (TBI). Studies have looked at the effects of injury severity, aetiology of injury and the stage at which visual problems become apparent. There was little discrepancy found between the frequencies or types of visual dysfunctions across blast and non-blast related groups, however complete sight loss appeared to occur only in those who had a blast-related injury. Generally, the more severe the injury, the greater the likelihood of specific visual disturbances occurring, and a study found total sight loss to only occur in cases with greater severity. Diagnosis of mild TBI (mTBI) is challenging. Being able to identify a potential TBI via visual symptoms may offer a new avenue for diagnosis.
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Affiliation(s)
- Syeda F. Hussain
- Research & Innovation, Blind Veterans UK, 12-14 Harcourt Street, London, W1H 4HD UK
- Bravo Victor, Research, 12-14 Harcourt Street, London, W1H 4HD UK
| | - Zara Raza
- Research & Innovation, Blind Veterans UK, 12-14 Harcourt Street, London, W1H 4HD UK
- Bravo Victor, Research, 12-14 Harcourt Street, London, W1H 4HD UK
| | - Andrew T. G. Cash
- Research & Innovation, Blind Veterans UK, 12-14 Harcourt Street, London, W1H 4HD UK
- Bravo Victor, Research, 12-14 Harcourt Street, London, W1H 4HD UK
| | - Thomas Zampieri
- Blinded Veterans Association, 1101 King Street, Suite 300, Alexandria, Virginia 22314 USA
| | - Robert A. Mazzoli
- Department of Ophthalmology, Madigan Army Medical Center, 9040 Jackson Avenue, Tacoma, Washington, 98431 USA
| | - Randy H. Kardon
- Iowa City VA Health Care System and Iowa City VA Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa 52246 USA
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa 52242 USA
| | - Renata S. M. Gomes
- Research & Innovation, Blind Veterans UK, 12-14 Harcourt Street, London, W1H 4HD UK
- Bravo Victor, Research, 12-14 Harcourt Street, London, W1H 4HD UK
- Northern Hub for Veterans and Military Families Research, Department of Nursing, Midwifery and Health, Faculty of Health and Life Sciences, Northumbria University, Newcastle, NE7 7XA UK
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Mozo Cuadrado M, Tabuenca Del Barrio L, Rodríguez Ulecia I, Urriza Mena J. Indirect traumatic optic neuropathy after blunt head trauma. J Fr Ophtalmol 2020; 43:e317-e320. [DOI: 10.1016/j.jfo.2019.11.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/19/2019] [Accepted: 11/20/2019] [Indexed: 10/23/2022]
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