Visualizing traumatic brain injury:ocular clues for diagnosis and assessment

Traumatic brain injury (TBI) is defined as damage to the brain resulting from an external sudden physical force or shock to the head.It is considered a silent public health epidemic causing significant death and disability globally.There were 64,000 TBI related deaths reported in the USA in 2020,with about US$76 billion in direct and indirect medical costs annually.

Necroptosis plays a crucial role in the exacerbation of retinal injury after blunt ocular trauma

Retinal injury after blunt ocular trauma may directly affect prognosis and lead to vision loss.To investigate the pathological changes and molecular mechanisms involved in retinal injury after blunt ocular trauma,we established a weight drop injury model of blunt ocular trauma in male Beagle dogs.Hematoxylin-eosin staining,immunofluorescence staining,western blotting,and TUNEL assays were performed to investigate retinal injury within 14 days after blunt ocular trauma.Compared with the control group,the thicknesses of the inner and outer nuclear layers,as well as the number of retinal ganglion cells,gradually decreased within 14 days after injury.The number of bipolar cells in the inner nuclear layer began to decrease 1 day after injury,while the numbers of cholinergic and amacrine cells in the inner nuclear layer did not decrease until 7 days after injury.Moreover,retinal cell necroptosis increased with time after injury;it progressed from the ganglion cell layer to the outer nuclear layer.Visual electrophysiological findings indicated that visual impairment began on the first day after injury and worsened over time.Additionally,blunt ocular trauma induced nerve regeneration and Müller glial hyperplasia;it also resulted in the recruitment of microglia to the retina and polarization of those microglia to the M1 phenotype.These findings suggest that necroptosis plays an important role in exacerbating retinal injury after blunt ocular trauma via gliosis and neuroinflammation.Such a role has important implications for the development of therapeutic strategies.

Acute Bacillus cereus endophthalmitis caused by ocular perforation injury and occult intravitreal cilium implantation:a case report

Dear Editor,We present a case of acute Bacillus cereus(B.cereus)endophthalmitis in a patient with an intraocular perforation injury combined with occult intravitreal cilium implantation.B.cereus endophthalmitis is a severe intraocular infection commonly caused by post-traumatic injuries.It often leads to significant vision loss or even eye loss within 12-48h[1].The presence of an intraocular foreign body(IOFB)increases the risk of infection,while early surgical removal of IOFBs can prevent endophthalmitis,some IOFBs are difficult to detect preoperatively.The Medical Ethics Review Board of West China Hospital of Sichuan University waived application for a clinical study because this was a retrospective report of a single patient based on imaging and because no human experimentation was involved.The patient provided written informed consent to use the imaging data for publication.

Epidemiology and etiology of chemical ocular injury:A brief review

Chemical ocular injury is one of the common ophthalmologic emergencies that can cause vision loss and serious complications.Despite all protective measures,it continues to be a serious public health problem,especially in young male patients.Although it is known that injuries occur most frequently in the workplace and in young male patients,there is a variable frequency and distribution in different regions around the world.In addition,with the coronavirus disease 2019 pandemic,there are changing trends in ocular chemical injuries.This review aims to specify an update on the epidemiological and etiological features of ocular chemical injuries.

Neuroprotective effect of mesenchymal stem cellderived extracellular vesicles on optic nerve injury in chronic ocular hypertension

Mesenchymal stem cells have neuroprotective effects that limit damage to the retina and photoreceptors,and which may be mediated by extracellular vesicles(or exosomes)released by mesenchymal stem cells.To investigate the neuroprotective effect of extracellular vesicles derived from umbilical cord mesenchymal stem cells on glaucoma,we established rat models of chronic ocular hypertension by injecting conjunctival fibroblasts into the anterior chamber to mimic optic nerve injury caused by glaucoma.One week after injury,extracellular vesicles derived from umbilical cord-derived mesenchymal stem cells were injected into the vitreous cavity.We found that extracellular vesicles derived from mesenchymal stem cells substantially reduced retinal damage,increased the number of retinal ganglion cells,and inhibited the activation of caspase-3.These findings suggest that mesenchymal stem cell-derived extracellular vesicles can help alleviate optic nerve injury caused by chronic ocular hypertension,and this effect is achieved by inhibiting cell apoptosis.

Reliability of the ocular trauma score for the predictability of traumatic and post-traumatic retinal detachment after open globe injury

AIM: To elucidate the question of whether the ocular trauma score(OTS) and the zones of injury could be used as a predictive model of traumatic and post traumatic retinal detachment(RD) in patients with open globe injury(OGI).METHODS: A retrospective observational chart analysis of OGI patients was performed. The collected variables consisted of age, date, gender, time of injury, time until repair, mechanism of injury, zone of injury, injury associated vitreous hemorrhage, trauma associated RD, post traumatic RD, aphakia at injury, periocular trauma and OTS in cases of OGI. RESULTS: Totally 102 patients with traumatic OGI with a minimum of 12 mo follow-up and a median age at of 48.6 y(range: 3-104 y) were identified. Final best corrected visual acuity(BCVA) was independent from the time of repair, yet a statistically significant difference was present between the final BCVA and the zone of injury. Severe trauma presenting with an OTS score Ⅰ(P<0.0001) or Ⅱ(P<0.0001) revealed a significantly worse BCVA at last follow up when compared to the cohort with an OTS score >Ⅲ. OGI associated RD was observed in 36/102 patients(35.3%), whereas post traumatic RD(defined as RD following 14 d after OGI) occurred in 37 patients(36.3%). OGI associated RD did not correlate with the OTS and the zone of injury(P=0.193), yet post traumatic RD correlated significantly with zone Ⅲ injuries(P=0.013). CONCLUSION: The study shows a significant association between lower OTS score and zone Ⅲ injury with lower final BCVA and a higher number of surgeries, but only zone Ⅲ could be significantly associated with a higher rate of RD.

Ocular injury resulting in eye removal at a large tertiary care center in China

AIM:To investigate the risk factors for eye removal following ocular trauma at a major ophthalmology department in China.METHODS:A retrospective study of patients who underwent eye removal surgery following ocular trauma was completed.Clinical outcomes were consulted in detail through the hospital’s computed medical data system.Patients’information including age,gender,cause of ocular trauma,affected eye,and education level was collected and recorded in a standardized database.Chi-squared test,Student’s t-test,Fisher’s exact test,and bivariate correlation analysis were used for statistical comparisons.RESULTS:The present study included 1675 removal eyes from 1674 patients over the 20-year period.Patients included 80.5%males and 19.5%females,with mean age of 38y.The majority of the patients(70.7%)were blue-collar workers(physical laborers),and 1098 patients(65.6%)did not receive high school education.Work-related injuries were the most common reason for eye removal(n=739,44.1%),of which 441 cases(59.7%)were related to metal/nail wounds.The most frequent injury type in males was work-related injuries(49.7%),whereas the most frequent injury type in females was home-related injuries(25.8%).CONCLUSION:Work-related injuries are a leading cause of severe ocular injury resulting in eye removal.In addition,men and undereducated patients are more likely to undergo eye removal surgery following ocular trauma.This study identified multiple high-risk factors leading to eye removal following ocular trauma,which is of great importance for preventing severe eye injuries.

Establishment of an acute extraocular muscle injury model in cats

AIM： To describe an acute extraocular muscle injury model in cats. METHODS： Seventy-two cats were randomly divided into 6 groups（12 cats per group）. Cats＇ left lateral recti were clamped using a surgical needle holder with a clamping strength of 2（Groups A and D）, 4（Groups B and E） and 6 kg（Groups C and F）. The right lateral recti were treated as controls. On the 4^（th） and 7^（th） days, hematoxylin eosin（HE） staining, immunohistochemical staining for proliferating cell nuclear antigen（PCNA）, muscle force measurements and ocular alignment changes were performed to evaluate the extent of injuries. RESULTS： The morphological changes were graded as mild, moderate or severe by HE staining in all experiment groups. PCNA immunohistochemical staining indicated repairment of muscle fibers in the damaged area. On the 4^（th） and 7^（th） days after clamping, the injured lateral muscle exhibited an elevated threshold for electric stimulation. The muscle forces among groups 2, 4 and 6 kg injury at 4 d（Groups A, B and C） were statistically significant（P0.05）, respectively. In addition, medial deviation in ocular alignment was also present to various degrees in all groups. CONCLUSION： A cat model of acute extraocular muscle injury can be established by rectus clamping. Different clamping strengths can make different degrees of muscle injury. This model may help the future study in the acute extraocular muscle injury.

Epidemiology of Child’s Ocular Globe Injury: A Retrospective Study at the University Teaching Hospital-Campus of Lomé(Togo)

Aim: To study clinical and epidemiological characteristics of child’s ocular injuries. Patients and Method: Retrospective study on medical records of children suffering from traumatic injuries of the ocular globe presented to the Campus Teaching Hospital (CHU Campus) of Lomé from 3 January 2015 to 30 June 2016 (18 months). Age, sex, nature of the traumatising agent, consultation delay and the width of the injury (zone I, II or III), the classification of ocular trauma, according to “Birmingham Eye Trauma Terminology (BETT) system”, connected lesions have been studied. Results: Twenty children about 46.51% children presented for ocular trauma have been suffering from a globe injury. The average age was 6.68 years with the extremes of 1 year and 12 years;the age bracket of 0 - 5 years was more represented (45%);predominance was more from the female with a sex-ratio = 0.67. Eighty percent of the children were from rural areas while twenty from urban areas. The delay of consultation was less than 24 hours in 40% of cases and 15% consulted between 24 h and 72 h after the trauma. Traumatisms were entirely unilateral and penetrating within a majority of 15 (75%) cases of which a “stick” is the traumatising agent of the most frequent (40%). The seat of the injury was the zone I (85.71%) and zone II (14.29%). Connected lesions were dominated by iris hernia 7 (35%) and traumatic cataract 6 (30%). Conclusion: children’s traumas were high predominantly and they came in majority from rural zones. Prevention through awareness remains the best treatment.

Does high intraocular pressure exclude an open globe injury?

Dear Sir,Ocular trauma is a topic of unresolved controversies and there are continuous controversial and debatable diagnostic and management strategies for open-globe injuries[1].Amongst many types of ocular trauma,the open globe injury is the most serious due to its very poor visual prognosis and young population of patients are mostly affected[2].The treatment outcome may be improved by prompt diagnosis,and immediate surgical repair performed to high standard[3].Amongst the other clinical signs the intraocular pressure(IOP)is found to be particularly reduced and conventionally this is considered as a very reliable indicator of occult globe

Mechanisms of vascular injury in neurotrauma: A critical review of the literature

One in every two individuals will experience a traumatic brain injury in their lifetime with significant impacts on the global economy and healthcare system each year.Neurovascular injury is a key aspect of neurotrauma to both the brain and the spinal cord and an important avenue of current and future research seeking innovative therapies.In this paper,we discuss primary and secondary neurotrauma,mechanisms of injury,the glymphatic system,repair and recovery.Each of these topics are directly connected to the vasculature of the central ner-vous system,affecting severity of injury and recovery.Consequently,neurova-scular injury in trauma represents a promising target for future therapeutics and innovation.

Blast injury risks to humans within a military trench

In land warfare,trenches serve as vital defensive fortifications,offering protection to soldiers while engaging in combat.However,despite their protective function,soldiers often sustain injuries within these trenches.The lack of corresponding blast data alongside empirical injury reports presents a significant knowledge gap,particularly concerning the blast pressures propagating within trench spaces following nearby explosions.This absence hinders the correlation between blast parameters,trench geometry,and reported injury cases,limiting our understanding of blast-related risks within trenches.This paper addresses the critical aspect of blast propagation within trench systems,essential for evaluating potential blast injury risks to individuals within these structures.Through advanced computational fluid dynamics(CFD)simulations,the study comprehensively investigates blast injury risks resulting from explosions near military trenches.Employing a sophisticated computational model,the research analyzes the dynamic blast effects within trenches,considering both geometrical parameters and blast characteristics influenced by explosive weight and scaled distance.The numerical simulations yield valuable insights into the impact of these parameters on blast injury risks,particularly focusing on eardrum rupture,lung injury,and traumatic brain injury levels within the trench.The findings elucidate distinct patterns of high-risk zones,highlighting unique characteristics of internal explosions due to confinement and venting dynamics along the trench.This study underscores the significance of detailed numerical modeling in assessing blast injury risks and provides a novel knowledge base for understanding risks associated with explosives detonating near military trenches.The insights gained contribute to enhancing safety measures in both military and civilian contexts exposed to blast events near trench structures.

Connecting cellular mechanisms and extracellular vesicle cargo in traumatic brain injury

Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial activation and neuroinflammation, edema, ischemia, vascular injury, energy failure, and peripheral immune cell infiltration. The timing of these events post injury has been linked to injury severity and functional outcome. Extracellular vesicles are membrane bound secretory vesicles that contain markers and cargo pertaining to their cell of origin and can cross the blood-brain barrier. These qualities make extracellular vesicles intriguing candidates for a liquid biopsy into the pathophysiologic changes occurring at the cellular level post traumatic brain injury. Herein, we review the most commonly reported cargo changes in extracellular vesicles from clinical traumatic brain injury samples. We then use knowledge from animal and in vitro models to help infer what these changes may indicate regrading cellular responses post traumatic brain injury. Future research should prioritize labeling extracellular vesicles with markers for distinct cell types across a range of timepoints post traumatic brain injury.

A comprehensive look at the psychoneuroimmunoendocrinology of spinal cord injury and its progression: mechanisms and clinical opportunities

Spinal cord injury(SCI)is a devastating and disabling medical condition generally caused by a traumatic event(primary injury).This initial trauma is accompanied by a set of biological mechanisms directed to ameliorate neural damage but also exacerbate initial damage(secondary injury).The alterations that occur in the spinal cord have not only local but also systemic consequences and virtually all organs and tissues of the body incur important changes after SCI,explaining the progression and detrimental consequences related to this condition.Psychoneuroimmunoendocrinology(PNIE)is a growing area of research aiming to integrate and explore the interactions among the different systems that compose the human organism,considering the mind and the body as a whole.The initial traumatic event and the consequent neurological disruption trigger immune,endocrine,and multisystem dysfunction,which in turn affect the patient's psyche and well-being.In the present review,we will explore the most important local and systemic consequences of SCI from a PNIE perspective,defining the changes occurring in each system and how all these mechanisms are interconnected.Finally,potential clinical approaches derived from this knowledge will also be collectively presented with the aim to develop integrative therapies to maximize the clinical management of these patients.

Feasibility of smart intraocular lens

Dear Editor,Wearable biosensors are monitoring implantable devices that provide real-time detection of biomarkers by means of non-invasive measurements[1].There is a high demand for novel sensors that can be comfortably used by the patients for clinical monitoring of ocular diseases.Transducers implanted into eyes have been improved and they have the capacity to monitor parameters such as intraocular pressure(IOP),and also have the possibility of recording lactic acid,glucose or cortisol levels[2-3].

Guiding function of positron emission tomographycomputed tomography examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma

AIM:To explore the role of positron emission tomographycomputed tomography(PET-CT)examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma(OAML).METHODS:The general clinical data,postoperative PET-CT results,treatment regimens,and the prognosis of 21 histopathologically confirmed OAML patients between October 2017 and September 2021 were collected.Among the 21 patients,five patients underwent surgical treatment alone,13 patients underwent surgical treatment combined with radiotherapy,and three patients underwent surgical treatment combined with chemotherapy.RESULTS:The follow-up period ranged from 8 to 79mo,with four cases of recurrence and no deaths.Through PETCT examination,two patients exhibited both local ocular metabolic elevation and systemic metastasis,and one of these patients had cervical lymph node metastasis,while the other had submandibular and parotid gland metastasis.Nine patients showed only local ocular metabolic elevation,while 10 patients had no abnormal metabolic activity locally.CONCLUSION:PET-CT examination plays a crucial role in detecting residual lesions and recurrence following tumor resection,aiding in precise disease staging,and facilitating the development of personalized treatment plans,ultimately improving patient prognosis.

Identification of injury type using somatosensory and motor evoked potentials in a rat spinal cord injury model

The spinal cord is at risk of injury during spinal surgery.If intraoperative spinal co rd injury is identified early,irreve rsible impairment or loss of neurological function can be prevented.Different types of spinal cord injury result in damage to diffe rent spinal cord regions,which may cause diffe rent somatosensory and motor evoked potential signal res ponses.In this study,we examined electrophysiological and histopathological changes between contusion,distra ction,and dislocation spinal cord injuries in a rat model.We found that contusion led to the most severe dorsal white matter injury and caused considerable attenuation of both somatosensory and motor evoked potentials.Dislocation resulted in loss of myelinated axons in the lateral region of the injured spinal cord along the rostrocaudal axis.The amplitude of attenuation in motor evoked potential responses caused by dislocation was greater than that caused by contusion.After distraction injury,extracellular spaces were slightly but not significantly enlarged;somatosensory evoked potential res ponses slightly decreased and motor evoked potential responses were lost.Correlation analysis showed that histological and electrophysiological findings we re significantly correlated and related to injury type.Intraope rative monitoring of both somatosensory and motor evoked potentials has the potential to identify iatrogenic spinal cord injury type during surgery.

Homer1a reduces inflammatory response after retinal ischemia/reperfusion injury

Elevated intraocular pressure(IOP)is one of the causes of retinal ischemia/reperfusion injury,which results in NRP3 inflammasome activation and leads to visual damage.Homerla is repo rted to play a protective role in neuroinflammation in the cerebrum.However,the effects of Homerla on NLRP3inflammasomes in retinal ischemia/reperfusion injury caused by elevated IOP remain unknown.In our study,animal models we re constructed using C57BL/6J and Homer1^(flox/-)/Homerla^(+/-)/Nestin-Cre^(+/-)mice with elevated IOP-induced retinal ischemia/repe rfusion injury.For in vitro expe riments,the oxygen-glucose deprivation/repe rfusion injury model was constructed with M uller cells.We found that Homerla ove rexpression amelio rated the decreases in retinal thickness and Muller cell viability after ischemia/reperfusion injury.Furthermore,Homerla knockdown promoted NF-κB P65^(Ser536)activation via caspase-8,NF-κB P65 nuclear translocation,NLRP3 inflammasome formation,and the production and processing of interleukin-1βand inte rleukin-18.The opposite results we re observed with Homerla ove rexpression.Finally,the combined administration of Homerla protein and JSH-23 significantly inhibited the reduction in retinal thickness in Homer1^(flox/-)Homer1a^(+/-)/Nestin-Cre^(+/-)mice and apoptosis in M uller cells after ischemia/reperfusion injury.Taken together,these studies demonstrate that Homer1a exerts protective effects on retinal tissue and M uller cells via the caspase-8/NF-KB P65/NLRP3 pathway after I/R injury.

Short-term fluctuation of intraocular pressure and influencing factors following intravitreal injection in patients with retinal vascular diseases

AIM:To investigate the patterns of short-term intraocular pressure(IOP)fluctuations and identify the contributing factors following intravitreal injection in patients with retinal vascular diseases.METHODS:Totally 81 patients were enrolled in this case control study.Eyes were categorized into 7 groups,including age-related macular degeneration(AMD),polypoidal choroidal vasculopathy(PCV),idiopathic choroidal neovascularization(CNV),proliferative diabetic retinopathy(PDR),diabetic macular edema(DME),macular edema secondary to branch(BVOME)and central(CVOME)retinal vein occlusion.IOP was measured in all patients using rebound tonometer at 7 preset time points perioperatively.Additionally,based on the administered medication,the eyes were classified into three treatment groups,including dexamethasone intravitreal implant(IVO),intravitreal conbercept(IVC),and intravitreal ranibizumab(IVR).To compare IOP values at various time points across groups,we employed one-way ANOVA,independent sample t-test or χ^(2) test and multivariate logistic regression analysis.RESULTS:Peak IOP values across all groups were observed at 40s,and 5min after intravitreal injection.Statistical differences in IOP were detected at the 5min among the 7 indication groups(F=2.50,P=0.029).When examing the impact of medications,the IVO group exhibited lower average IOP values at both 40s and 5min compared to the IVC and IVR groups(P<0.001;P=0.007).The IOP values at 40s and 5min were significantly higher in BVOME and CVOME group compared to non-retinal vein occlusionsecondary macular edema(RVOME)group(P<0.001).Multivariate logistic regression analysis further confirmed that IOP measurement at 40s was significantly higher in CVOME group than in non-RVOME group(OR=1.64,95%CI:1.09-2.47;P=0.018).CONCLUSION:Needle size plays a crucial role in the transient changes of IOP following intravitreal injection.Before administering intravitreal injection to patients with central retinal vein occlusion,it is essential to exclude any underlysing causes of increased IOP.

Effi cacy of partial and complete resuscitative endovascular balloon occlusion of the aorta in the hemorrhagic shock model of liver injury

BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic bleeding.However,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBOA)can alleviate ischemic burden;however,its security and eff ectiveness prior to operative hemorrhage control remains unknown.Hence,we aimed to estimate the effi cacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic gun.METHODS:Twenty Landrace pigs were randomized into control(no aortic occlusion)(n=5),intervention with complete REBOA(cREBOA)(n=5),continuous pREBOA(C-pREBOA)(n=5),and sequential pREBOA(S-pREBOA)(n=5)groups.In the cREBOA and C-pREBOA groups,the balloon was inflated for 60 min.The hemodynamic and laboratory values were compared at various observation time points.Tissue samples immediately after animal euthanasia from the myocardium,liver,kidneys,and duodenum were collected for histological assessment using hematoxylin and eosin staining.RESULTS:Compared with the control group,the survival rate of the REBOA groups was prominently improved(all P<0.05).The total volume of blood loss was markedly lower in the cREBOA group(493.14±127.31 mL)compared with other groups(P<0.01).The pH was significantly lower at 180 min in the cREBOA and S-pREBOA groups(P<0.05).At 120 min,the S-pREBOA group showed higher alanine aminotransferase(P<0.05)but lower blood urea nitrogen compared with the cREBOA group(P<0.05).CONCLUSION:In this trauma model with liver injury,a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure,despite persistent hemorrhage.Extended tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures,and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.