Early versus Delayed Timing of Primary Repair after Open-Globe Injury: A Systematic Review and Meta-analysis.

TOPIC: The timing of primary repair of open-globe injury is variable in major trauma centers worldwide, and consensus on optimal timing is lacking. CLINICAL RELEVANCE: Surgery is the mainstay of open-globe injury management, and appropriate timing of surgical repair may minimize the risk of potentially blinding complications such as endophthalmitis, thereby optimizing visual outcomes. METHODS: A systematic literature review was performed following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines (International Prospective Register of Systematic Reviews identifier, CRD42023442972). The Cochrane Central Register of Controlled Trials, MEDLINE, Embase, and ISRCTN registries and ClinicalTrials.gov were searched from inception through October 29, 2023. Prospective and retrospective nonrandomized studies of patients with open-globe injury with a minimum of 1 month of follow-up after primary repair were included. Primary outcomes included visual acuity at last follow-up and the proportion of patients with endophthalmitis. Certainty of the evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. RESULTS: Fifteen studies met inclusion criteria, reporting a total of 8497 eyes. The most common injury types were penetrating and intraocular foreign body (IOFB). Meta-analysis found that primary repair less than 24 hours after open-globe injury was associated with 0.30 odds of endophthalmitis compared with primary repair conducted more than 24 hours after trauma (odds ratio, 0.39; 95% confidence interval [CI], 0.19-0.79; I2 = 95%; P = 0.01). No significant difference was found in reported visual outcomes between patients whose open-globe injuries were repaired more than, compared with less than, 24 hours after trauma (odds ratio, 0.89; 95% CI, 0.61-1.29; I2 = 70%; P = 0.52). All included studies were retrospective and nonrandomized, demonstrating an overall low certainty of evidence on GRADE assessment. DISCUSSION: Only retrospective data exist around the effect of timing of open-globe repair, resulting in low certainty of the available evidence. However, this review of current evidence, predominantly including penetrating and IOFB injuries, suggests that primary repair performed less than 24 hours after open-globe injury is associated with a reduced endophthalmitis rate compared with longer delays, consistent with delay to primary repair increasing endophthalmitis risk. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

The Risk of Sympathetic Ophthalmia Associated with Open-Globe Injury Management Strategies: A Meta-analysis.

TOPIC: Sympathetic ophthalmia (SO) is a sight-threatening granulomatous panuveitis caused by a sensitizing event. Primary enucleation or primary evisceration, versus primary repair, as a risk management strategy after open-globe injury (OGI) remains controversial. CLINICAL RELEVANCE: This systematic review was conducted to report the incidence of SO after primary repair compared with that of after primary enucleation or primary evisceration. This enabled the reporting of an estimated number needed to treat. METHODS: Five journal databases were searched. This review was registered with International Prospective Register of Systematic Reviews (identifier, CRD42021262616). Searches were carried out on June 29, 2021, and were updated on December 10, 2022. Prospective or retrospective studies that reported outcomes (including SO or lack of SO) in a patient population who underwent either primary repair and primary enucleation or primary evisceration were included. A systematic review and meta-analysis were carried out in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Random effects modelling was used to estimate pooled SO rates and absolute risk reduction (ARR). RESULTS: Eight studies reporting SO as an outcome were included in total. The included studies contained 7500 patients and 7635 OGIs. In total, 7620 OGIs met the criteria for inclusion in this analysis; SO developed in 21 patients with OGI. When all included studies were pooled, the estimated SO rate was 0.12% (95% confidence interval [CI], 0.00%-0.25%) after OGI. Of 779 patients who underwent primary enucleation or primary evisceration, no SO cases were reported, resulting in a pooled SO estimate of 0.05% (95% CI, 0.00%-0.21%). For primary repair, the pooled estimate of SO rate was 0.15% (95% CI, 0.00%-0.33%). The ARR using a random effects model was -0.0010 (in favour of eye removal; 95% CI, -0.0031 [in favor of eye removal] to 0.0011 [in favor of primary repair]). Grading of Recommendations, Assessment, Development, and Evaluations analysis highlighted a low certainty of evidence because the included studies were observational, and a risk of bias resulted from missing data. DISCUSSION: Based on the available data, no evidence exists that primary enucleation or primary evisceration reduce the risk of secondary SO. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

A Case of Bing-Neel Syndrome Presenting Like Giant Cell Arteritis.

ABSTRACT: A 55-year-old woman presented with new-onset headache, scalp tenderness, shoulder arthralgias, night sweats, and loss of appetite. She was diagnosed with giant cell arteritis by her primary care physician and commenced on oral corticosteroids. However, her headache, scalp tenderness, and night sweats persisted. She then developed right Horner syndrome and trigeminal hypoesthesia. Extensive blood work-up revealed mildly elevated inflammatory markers and a paraproteinemia. Subsequent bone marrow biopsy showed lymphoplasmacytic lymphoma, with 10% of hemopoiesis, and staging led to the diagnosis of Waldenstrom macroglobulinemia without nodal or central nervous system (CNS) lesions. Immunohistochemical staining of a temporal artery biopsy showed perivascular lymphoplasmacytic cells and paraprotein deposits. She was diagnosed with CNS involvement of her macroglobulinemia-Bing-Neel syndrome (BNS). Identification of rare CNS involvement of lymphoma is challenging when a patient is already on steroid immunosuppression. In the absence of clear diagnostic criteria, the rare and heterogenous BNS remains a clinical diagnosis.

Visual deterioration in patients with photoreceptor loss after retinal reattachment surgery.

PURPOSE: Assess the relationship between photoreceptor degeneration and visual function after retinal reattachment surgery (RRS) in a prospective cohort. METHODS: Patients with rhegmatogenous retinal detachment (RRD) were reviewed before and 6 months after vitreoretinal surgery. Optical coherence tomographical thickness of the outer nuclear layer (ONL), outer retinal segment (ORS), retinal pigmented epithelium to ellipsoid zone (RPE-EZ) and external limiting membrane to EZ (ELM-EZ) were recorded 6 months post-operatively. These were compared to best corrected visual acuity (BCVA) and retinal sensitivity (Humphrey visual field). RESULTS: Thirteen macula-off and 8 macula-on RRD patients were included. The mean ONL thickness was higher after macula-on RRD compared to macula-off RRD (97.70 ± 3.62 µm vs. 73.10 ± 4.98 µm). In all RRD eyes, every 1 µm decrease in ONL thickness correlated with a 0.052 dB decrease and in retinal sensitivity and every 1 µm decrease in ORS thickness was associated with a 0.062 dB reduction in retinal sensitivity. ORS, ELM-EZ and RPE-EZ thickness did not correlate with BCVA post-RRS. CONCLUSION: There was greater ONL and ORS thinning following macula-off compared to macula-on RRD. Correlations between ONL and ORS thinning with decreased retinal sensitivity may be explained by RRD-induced photoreceptor death.

Comparing the Management of Eye Injuries by Coalition Military Surgeons during the Iraq and Afghanistan Conflicts.

PURPOSE: To compare incidences, ocular injury types, and treatment performed on United States and United Kingdom military service members and host nation civilians within the Iraq and Afghanistan conflicts to inform future military surgical training requirements and military medical planning. The United States routinely deployed ophthalmologists, whereas the United Kingdom did not. DESIGN: Retrospective cohort study of the United States and United Kingdom military Joint Theatre Trauma Registries. PARTICIPANTS: All patients with eye injuries treated at a deployed Military Treatment Facility between March 2003 and October 2011. METHODS: An adjusted multiple logistic regression model was performed using enucleation or evisceration and primary open-globe repair as dependent variables and casualty nationality, location, and the presence of an ophthalmic surgeon as independent variables. MAIN OUTCOME MEASURES: Incidence of eye removal (enucleation or evisceration) or primary repair for open globe injury. RESULTS: Five thousand seven hundred nineteen of 67 586 (8%) survivors or those who died of wounds were recorded to have sustained eye injuries. The most common eye injuries were open-globe injury without intraocular foreign body (3201/5719 [56%]). Adnexal injuries (eyelid lacerations and damage to lacrimal apparatus) were recorded in 1265 of 5719 patients (22%). The odds of undergoing evisceration or enucleation for open-globe injury was highest in host nation civilians (odds ratio [OR], 9.23; P < 0.001), but there was no evidence of a difference between United States and United Kingdom military service member casualties (P = 0.38). The presence of an ophthalmic surgeon (OR, 16.3; P < 0.001) significantly affected the odds of eye removal. CONCLUSIONS: Eye injuries were more likely to have been treated definitively in United States Medical Treatment Facilities (MTFs), reflecting the absence of ophthalmologists in most deployed United Kingdom MTFs. The Iraq and Afghan conflicts were notable for coalition air dominance; the shape of future conflicts may mandate delays in evacuation, which may affect visual outcomes negatively, particularly if primary repair of patients with open-globe injuries is delayed. This study provides evidence to support the maintenance of specialist ophthalmic surgical competencies in deployed coalition MTFs for future conflicts.

Assessment of necroptosis in the retina in a repeated primary ocular blast injury mouse model.

Primary blast injury (caused by the initial rapid increase in pressure following an explosive blast) to the retina and optic nerve (ON) causes progressive visual loss and neurodegeneration. Military personnel are exposed to multiple low-overpressure blast waves, which may be in quick succession, such as during breacher training or in combat. We investigated the necroptotic cell death pathway in the retina in a mouse repeated primary ocular blast injury (rPBI) model using immunohistochemistry. We further evaluated whether intravitreal injections of a potent necroptosis inhibitor, Necrostatin-1s (Nec-1s), protects the retina and ON axons by retinal ganglion cells (RGC) counts, ON axonal counting and optical coherence tomography (OCT) analysis of vitreous haze. Receptor interacting protein kinase (RIPK) 3, increased in the inner plexiform layer 2 days post injury (dpi) and persisted until 14 dpi, whilst RIPK1 protein expression did not change after injury. The number of degenerating ON axons was increased at 28 dpi but there was no evidence of a reduction in the number of intact ON axons or RNA-binding protein with multiple splicing (RBPMS)+ RGC in the retina by 28 dpi in animals not receiving any intravitreal injections. But, when intravitreal injections (vehicle or Nec-1s) were given there was a significant reduction in RBPMS+ RGC numbers, suggesting that rPBI with intraocular injections is damaging to RGC. There were fewer RGC lost after Nec-1s than vehicle injection, but there was no effect of Nec-1s or vehicle treatment on the number of degenerating axons. OCT analysis demonstrated no effect of rPBI on vitreous haze, but intravitreal injection combined with rPBI increased vitreous haze (P = 0.004). Whilst necroptosis may be an active cell death signalling pathway after rPBI, its inhibition did not prevent cell death, and intravitreal injections in combination with rPBI increased vitreous inflammation and reduced RBPMS+ RGC numbers, implying intravitreal injection is not an ideal method for drug delivery after rPBI.

Influence of Optic Nerve Appearance on Visual Outcome in Pediatric Idiopathic Intracranial Hypertension.

OBJECTIVES: To determine whether optic disc hemorrhages (ODH) and cotton wool spots (CWS) at presentation are associated with worse visual outcomes in pediatric patients with idiopathic intracranial hypertension (IIH). METHODS: Retrospective institutional review of 100 eyes of 50 consecutive pediatric IIH patients (aged 16 years or less) who had baseline optic disc photographs before or within 30 days of their diagnostic lumbar puncture and initiation of medical treatment. Optic disc photographs were independently graded by three ophthalmologists in a standardized manner. Visual function was assessed using visual acuity (VA) and visual field grade (VFG). RESULTS: At least one ODH was found in 41% of eyes, at least one CWS was found in 27% of eyes, and 20% of eyes had both ODH and CWS. At presentation, Frisén grade was associated with the presence of CWS (p = 0.013) and showed no association with ODH (p = 0.060). When controlling for Frisén grade, ODH and CWS were not associated with worse VA or VFG at final follow-up. Severe ODH were associated with worse VA and VFG at presentation (p < 0.03), but not at final follow-up. Severe CWS at presentation was strongly associated with a worse Humphrey mean deviation of 5.0 dB (95% confidence interval 1.6-8.3) at final follow-up (p = 0.002). CONCLUSION: When controlling for the severity of papilledema, ODH do not provide any additional prognostic value in pediatric IIH patients. Frisén grade and severe CWS at presentation were independently associated with worse visual outcomes at the final follow-up.

Self-Reported Weight and Height Among Idiopathic Intracranial Hypertension Patients.

BACKGROUND: Idiopathic intracranial hypertension (IIH) mostly affects overweight and obese women. Severe obesity is associated with poorer visual outcomes in IIH, and weight gain can precipitate IIH and increase the risk of recurrence. Conversely, weight loss can decrease intracranial pressure and is an effective IIH treatment. Therefore, accurate monitoring of weight and body mass index (BMI) is important to help guide the management of IIH patients. Our goal was to compare estimated and measured BMI among patients with presumed IIH and non-IIH controls to determine whether these vital signs should be systematically measured when evaluating patients for IIH. METHODS: A retrospective chart review was performed of consecutive patients with reported and measured weight and height seen in one ophthalmology-based neuro-ophthalmology clinic for IIH between January 2, 2018 and September 10, 2018. Patients with IIH or presumed IIH were compared to non-IIH controls, matched according to age (±5 years), BMI (±5 kg/m unless ≥40 kg/m), sex, and race. Patients with confirmed IIH were asked to self-report their weight when seen in follow-up and they were weighed to compare their self-reported vs measured percent weight change. RESULTS: We included 379 subjects (140 patients; 239 controls) among whom 75 of the IIH patients were matched to non-IIH controls. Patients with presumed or definite IIH accurately estimated their height and generally underestimated their weight by a median of 1.8 kg (4 lb), resulting in a median BMI underestimate of 0.9 kg/m. There was no difference in BMI underestimation when comparing presumed or definite IIH patients to matched non-IIH controls while controlling for insurance status, smoking, diabetes, and vascular disease (P = 0.66). As BMI increased, all subjects underestimated their BMI more (by 0.9% per 10 measured BMI unit increase), when controlling for age, sex, and race (P < 0.003). Sixteen confirmed IIH patients were seen in follow-up. At initial neuro-ophthalmology consultation, these subjects underestimated their weight by a mean of 3.2%. At last follow-up they underestimated their weight by only 1.2% (P = 0.03). CONCLUSIONS: There was no evidence that IIH or presumed IIH patients had a different perception of their weight than non-IIH controls at initial neuro-ophthalmology consultation. Both patients and matched controls tended to underestimate their weight by the same amount, resulting in an overall BMI underestimation of approximately 1% per 10 measured BMI unit increase. Heavier subjects tended to underestimate their body weight and resultant BMI more, and IIH patients tended to estimate their weight more accurately at follow-up. Our results emphasize the need to systematically objectively measure the weight of presumed IIH patients seen in an ophthalmology clinic.

TGF-ß-induced IOP elevations are mediated by RhoA in the early but not the late fibrotic phase of open angle glaucoma.

Purpose: Elevations in intraocular pressure (IOP) are associated with the development of glaucoma and loss of sight. High transforming growth factor-ß (TGF-ß) 1 levels in the eye's anterior chamber can lead to dysfunctional contractions through RhoA signaling in trabecular meshwork (TM) cells and IOP spikes. Sustained high TGF-ß levels leads to TM fibrosis and sustained increases in IOP. We investigated whether inhibiting RhoA, using a siRNA-mediated RhoA (siRhoA), controls IOP by altering TM expression of fibrosis and contractility-related proteins in a rodent model of glaucoma. Methods: TGF-ß was injected intracamerally twice a week into adult Sprague Dawley rats, and IOP was recorded with tonometry. Animals were euthanized on day 7 and 35 with TM expression of fibrosis and contractility-related proteins, as well as survival of retinal ganglion cells (RGCs) assessed with immunohistochemistry. siRNA against RhoA or enhanced green fluorescent protein (EGFP) was also injected intracamerally into select animals. Successful RhoA knockdown was determined with quantitative reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry, and the effects of the knockdown on the parameters above analyzed. Results: TGF-ß caused increased TM contractile proteins and IOP spikes by day 7, sustained increases in IOP from day 15, and TM fibrosis at day 35. siRhoA abolished the transient 7 day IOP rise but not the later sustained IOP increase (due to fibrosis). At 35 days, TGF-ß-related RGC loss was not prevented with siRhoA treatment. Conclusions: We conclude that RhoA signaling mediates the early IOP rise induced by TM cellular changes associated with contractility but not the sustained IOP elevation caused by TM fibrosis. Thus, RhoA therapies offer a clinically relevant opportunity for IOP management, likely through the modulation of TM contractility, but appear to be ineffective in the amelioration of fibrosis.

Optical coherence tomography retinal ganglion cell complex analysis for the detection of early chiasmal compression.

PURPOSE: To report patients with sellar tumors and chiasmal compression with normal visual fields, who demonstrate damage to the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) on optical coherence tomography (OCT). METHODS: Seven patients with sellar tumors causing mass effect on the optic chiasm without definite visual field defect, but abnormal GCC are described. GCC/RNFL analyses using Cirrus-OCT were classified into centiles based on the manufacturer's reference range. RESULTS: In seven patients with radiologic compression of the chiasm by a sellar tumor, OCT-GCC thickness detected compressive chiasmopathy before visual defects became apparent on standard automated visual field testing. Without OCT, our patients would have been labelled as having normal visual function and no evidence of compressive chiasmopathy. With only OCT-RNFL analysis, 3/7 patients would still have been labelled as having no compression of the anterior visual pathways. CONCLUSIONS: These patients show that OCT-GCC analysis is more sensitive than visual field testing with standard automated perimetry in the detection of compressive chiasmopathy or optic neuropathy. These cases and previous studies suggest that OCT-GCC analysis may be used in addition to visual field testing to evaluate patients with lesions compressing the chiasm.

Mesenchymal stromal cell-mediated neuroprotection and functional preservation of retinal ganglion cells in a rodent model of glaucoma.

BACKGROUND AIMS: Glaucoma is a leading cause of irreversible blindness involving loss of retinal ganglion cells (RGC). Mesenchymal stromal cells (MSC) have shown promise as a paracrine-mediated therapy for compromised neurons. It is, however, unknown whether dental pulp stem cells (DPSC) are effective as a cellular therapy in glaucoma and how their hypothesized influence compares with other more widely researched MSC sources. The present study aimed to compare the efficacy of adipose-derived stem cells, bone marrow-derived MSC (BMSC) and DPSC in preventing the loss of RGC and visual function when transplanted into the vitreous of glaucomatous rodent eyes. METHODS: Thirty-five days after raised intraocular pressure (IOP) and intravitreal stem cell transplantation, Brn3a(+) RGC numbers, retinal nerve fibre layer thickness (RNFL) and RGC function were evaluated by immunohistochemistry, optical coherence tomography and electroretinography, respectively. RESULTS: Control glaucomatous eyes that were sham-treated with heat-killed DPSC had a significant loss of RGC numbers, RNFL thickness and function compared with intact eyes. BMSC and, to a greater extent, DPSC provided significant protection from RGC loss and RNFL thinning and preserved RGC function. DISCUSSION: The study supports the use of DPSC as a neuroprotective cellular therapy in retinal degenerative disease such as glaucoma.

Traumatic optic neuropathy management: a systematic review.

BACKGROUND: Traumatic optic neuropathy is classically described in up to 8% of patients with traumatic brain injury (TBI), but subclinical or undiagnosed optic nerve damage is much more common. When more sensitive testing is performed, at least half of patients with moderate to severe TBI demonstrate visual field defects or optic atrophy on examination with optical coherence tomography. Acute optic nerve compression and ischaemia in orbital compartment syndrome require urgent surgical and medical intervention to lower the intraocular pressure and diminish the risk of permanent optic nerve dysfunction. Other manifestations of traumatic optic neuropathy have more variable treatments in international practice. METHODS: We conducted a systematic review of traumatic optic neuropathy treatments in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. RESULTS: We included three randomised controlled trials of intravenous methylprednisolone (IVMP), erythropoietin, and levodopa-carbidopa combination, with no evidence of benefit for any treatment. In addition, large studies in TBI have found strong evidence of increased mortality in patients treated with megadose IVMP. CONCLUSIONS: There is therefore no evidence of benefit for any medical treatment and strong evidence of harm from IVMP. There is also no evidence of benefit for optic canal decompression for traumatic optic neuropathy. Orbital compartment syndrome is a separate entity that requires both medical and surgical interventions to prevent visual loss.

Management of open globe injury: a narrative review.

Open globe injuries are a significant global cause of visual loss, including unilateral and bilateral blindness. Prognosis is predicted by injury severity, with lower presenting visual acuity and more posterior injuries associated with poor visual outcomes, although even the most severely injured eyes with no perception of light vision may regain some visual function. In addition to severity of the primary injury, the secondary injuries and complications causing poor outcomes include proliferative vitreoretinopathy (PVR) and endophthalmitis. Endophthalmitis is common after open globe injury, affecting up to 16.5% of patients. Systemic antibiotic prophylaxis is commonly used, with a limited evidence base, while intraocular antibiotics are less commonly used but have stronger supporting evidence of efficacy. Endophthalmitis rates are also reduced by prompt primary repair, which may also support recovery of visual acuity. PVR is not prevented or treated by any pharmacologic interventions in current clinical practice, but the incidence of post-traumatic PVR may be reduced by early vitrectomy within the first 4-7 days after injury. Ocular trauma training is often limited in Western ophthalmic surgical training programmes, and patients with ocular trauma often require the input of multiple subspecialists. In this context, it is important that patients have an overview and coordination of the different aspects of their care, with ownership by one lead clinician.

Oculomic stratification of COVID-19 patients' intensive therapy unit admission status and mortality by retinal morphological findings.

To investigate if retinal thickness has predictive utility in COVID-19 outcomes by evaluating the statistical association between retinal thickness using OCT and of COVID-19-related mortality. Secondary outcomes included associations between retinal thickness and length of stay (LoS) in hospital. In this retrospective cohort study, OCT scans from 230 COVID-19 patients admitted to the Intensive Care Unit (ITU) were compared with age and gender-matched patients with pneumonia from before March 2020. Total retinal, GCL + IPL, and RNFL thicknesses were recorded, and analysed with systemic measures collected at the time of admission and mortality outcomes, using linear regression models, Pearson's R correlation, and Principal Component Analysis. Retinal thickness was significantly associated with all-time mortality on follow up in the COVID-19 group (p = 0.015), but not 28-day mortality (p = 0.151). Retinal and GCL + IPL layer thicknesses were both significantly associated with LoS in hospital for COVID-19 patients (p = 0.006 for both), but not for patients with pneumonia (p = 0.706 and 0.989 respectively). RNFL thickness was not associated with LoS in either group (COVID-19 p = 0.097, pneumonia p = 0.692). Retinal thickness associated with LoS in hospital and long-term mortality in COVID-19 patients, suggesting that retinal structure could be a surrogate marker for frailty and predictor of disease severity in this group of patients, but not in patients with pneumonia from other causes.

Understanding how traumatic brain injury-related changes in fluid biomarkers affect quality of life outcomes in veterans: a prospective observational trial protocol (UNTANGLE).

INTRODUCTION: Traumatic brain injury (TBI) is a major cause of disability, with annual global incidence estimated as 69 million people. Survivors can experience long-term visual changes, altered mental state, neurological deficits and long-term effects that may be associated with mental illness. TBI is prevalent in military personnel due to gunshot wounds, and blast injury. This study aims to evaluate the relationship between evolving visual, biochemical and mental health changes in both military veterans and civilians, suffering from TBI, and detect preliminary indicators of prognosis for TBI recovery, and quality-of-life outcomes. METHODS AND ANALYSIS: UNTANGLE is a 24-month prospective observational pilot study recruiting three patient groups: civilians with acute moderate-severe TBI, military veterans with diagnosis of a previous TBI and a control group of civilians or veterans with no history of a previous TBI. Patients will undergo visual, biochemical and mental health assessments, as well as patient-reported quality of life outcome measures over the course of a 1-year follow-up period. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Health Research Authority and Health and Care Research Wales with a REC reference number of 23/NW/0203. The results of the study will be presented at scientific meetings and published in peer-reviewed journals, including both civilian and military-related publications. We will also present our findings at national and international meetings of learnt neuroscience and neuropsychiatry and military societies. We anticipate that our pilot study will inform a larger study on the long-term outcomes of TBI and quality of life, specific to military veterans, such that potential interventions may be accessed as quickly as possible. TRIAL REGISTRATION NUMBER: ISRCTN13276511.

A systematic review of optical coherence tomography findings in adults with mild traumatic brain injury.

Mild traumatic brain injury (mTBI) is common with many patients suffering disabling long-term sequelae, with visual symptoms frequently reported. There are no objective biomarkers of mTBI that are routinely used in clinical practice. Optical coherence tomography (OCT) has been used in mTBI research, as it enables visualisation of the neuroretina, allowing measurement of the retinal nerve fibre layer and ganglion cell layer. This systematic review aims to appraise the available literature and assess whether there are significant changes within the retinal nerve fibre layer and ganglion cell layer in subjects after mTBI. A systematic review was carried out in accordance with PRISMA guidelines and registered with PROSPERO (Number: CRD42022360498). Four databases were searched for relevant literature published from inception until 1 September 2022. Abstracts and full texts were screened by three independent reviewers. Initial screening of databases yielded 341 publications, of these, three fulfilled all the criteria for inclusion. All three studies showed thinning of the retinal nerve fibre layer, whereas there were no significant changes in the ganglion cell layer. This systematic review demonstrated that thinning of the retinal nerve fibre layer (but not of the ganglion cell layer) is associated with mTBI. It provides preliminary evidence for the use of the retinal nerve fibre layer as a potential biomarker of damage to the visual system in mTBI. Further prospective longitudinal studies ensuring uniform diagnosis and accurate phenotyping of mTBI are needed to understand the effects on the visual system and potential of OCT as a prognostic biomarker.

Improving corneal permeability of dexamethasone using penetration enhancing agents: First step towards achieving topical drug delivery to the retina.

With an ever-increasing burden of vision loss caused by diseases of the posterior ocular segment, there is an unmet clinical need for non-invasive treatment strategies. Topical drug application using eye drops suffers from low to negligible bioavailability to the posterior segment as a result of static and dynamic defensive ocular barriers to penetration, while invasive delivery systems are expensive to administer and suffer potentially severe complications. As the cornea is the main anatomical barrier to uptake of topically applied drugs from the ocular surface, we present an approach to increase corneal permeability of a corticosteroid, dexamethasone sodium-phosphate (DSP), using a novel penetration enhancing agent (PEA). We synthesised a novel polyacetylene (pAc) polymer and compared its activity to two previously described cell penetrating peptide (CPP) based PEAs, TAT and penetratin, with respect to increasing transcorneal permeability of DSP in a rapid ex-vivo porcine corneal assay over 60 min. The transcorneal apparent permeability coefficients (Papp) for diffusion of pAc, and fluorescein isothiocyanate (FITC) conjugated TAT and penetratin were up to 5 times higher (p < 0.001), when compared to controls. When pAc was used in formulation with DSP, an almost 5-fold significant increase was observed in Papp of DSP across the cornea (p = 0.0130), a significant 6-fold increase with TAT (p = 0.0377), and almost 7-fold mean increase with penetratin (p = 0.9540). Furthermore, we investigated whether the PEAs caused any irreversible damage to the barrier integrity of the corneal epithelium by measuring transepithelial electrical resistance (TEER) and immunostaining of tight junction proteins using zonula occludens-1 (ZO-1) and occludin antibodies. There was no damage or structural toxicity, and the barrier integrity was preserved after PEA application. Finally, an in-vitro cytotoxicity assessment of all PEAs in human retinal pigment epithelium cells (ARPE-19) demonstrated that all PEAs were very well-tolerated, with IC50 values of 64.79 mM for pAc and 1335.45 µM and 87.26 µM for TAT and penetratin, respectively. Our results suggest that this drug delivery technology could potentially be used to achieve a significantly higher intraocular therapeutic bioavailability after topical eye drop administration, than currently afforded.

Optical coherence tomography angiography analysis methods: a systematic review and meta-analysis.

Optical coherence tomography angiography (OCTA) is widely used for non-invasive retinal vascular imaging, but the OCTA methods used to assess retinal perfusion vary. We evaluated the different methods used to assess retinal perfusion between OCTA studies. MEDLINE and Embase were searched from 2014 to August 2021. We included prospective studies including ≥ 50 participants using OCTA to assess retinal perfusion in either global retinal or systemic disorders. Risk of bias was assessed using the National Institute of Health quality assessment tool for observational cohort and cross-sectional studies. Heterogeneity of data was assessed by Q statistics, Chi-square test, and I2 index. Of the 5974 studies identified, 191 studies were included in this evaluation. The selected studies employed seven OCTA devices, six macula volume dimensions, four macula subregions, nine perfusion analyses, and five vessel layer definitions, totalling 197 distinct methods of assessing macula perfusion and over 7000 possible combinations. Meta-analysis was performed on 88 studies reporting vessel density and foveal avascular zone area, showing lower retinal perfusion in patients with diabetes mellitus than in healthy controls, but with high heterogeneity. Heterogeneity was lowest and reported vascular effects strongest in superficial capillary plexus assessments. Systematic review of OCTA studies revealed massive heterogeneity in the methods employed to assess retinal perfusion, supporting calls for standardisation of methodology.

Temporary Keratoprosthesis and Primary Corneal Graft for Ocular Trauma: A Systematic Review and Meta-Analysis.

PURPOSE: When severe retinal and corneal injury occur together, a temporary keratoprosthesis (TKP) is often a last resort to allow posterior segment visualization to enable vitreoretinal surgery, followed by a penetrating keratoplasty (PKP) which can restore corneal clarity in a single operation. We aimed to assess visual outcomes following combined PKP and vitreoretinal surgery with the use of a TKP for cases of ocular trauma. DESIGN: A systematic literature review was performed following PRISMA guidelines (PROSPERO registration number: CRD42023423518). METHODS: CENTRAL, MEDLINE, Embase, ISRCTN registry, and ClinicalTrials.gov were searched from inception to 27 April 2023. Randomized and nonrandomized studies assessing visual outcomes after combined vitreoretinal surgery and PKP with the use of a TKP after ocular trauma were eligible for inclusion. Outcomes included change in best corrected visual acuity, corneal graft survival and retinal reattachment at final follow up. Proportional meta-analysis was used to estimate the overall rate of the primary outcomes. Risk of bias for nonrandomized studies was assessed using the Joanna Briggs Institute (JBI) critical appraisal checklist for case series. RESULTS: A total of 19 studies met inclusion criteria reporting a total of 352 eyes. All studies were retrospective and nonrandomized with follow up times ranging from 6 to 91 months, with at least 79% of outcomes reported after 6 months. After combined surgery the rate of corneal graft survival was 52% (95% CI 0.41-0.62; I2 60%) successful retinal attachment was 79% (95% CI 0.73-0.84; I2 0%). and improved visual acuity, when compared to no change or decrease in visual acuity, was 45% (95% CI 0.32-0.59; I2 66%). CONCLUSION: Patients with severe injury affecting the anterior and posterior segments have very limited treatment options. This systematic review found that when combined vitreoretinal surgery and PKP with a TKP are performed, approximately half of corneal grafts survive, anatomically successful retinal reattachment is likely, and a similar proportion of patients benefit in terms of improved visual acuity, compared to their preoperative function. This systematic review of the available literature may help inform surgeons of the benefits of using a TKP for cases of ocular trauma.

Visual outcomes after blunt ocular trauma.

OBJECTIVE: To describe the prognosis and retinal location in patients presenting with acute traumatic maculopathy and extramacular retinal injuries. DESIGN: Retrospective, noninterventional case series. PARTICIPANTS AND CONTROLS: All patients presenting with commotio retinae or sclopetaria retinae to the Birmingham Midland Eye Centre Eye Casualty from October 1, 2007, to February 23, 2011. METHODS: The notes of all patients presenting with ocular trauma in the specified time period were examined to identify suitable patients and demographic and injury data were extracted. MAIN OUTCOME MEASURES: Outcome was assessed by visual acuity (VA). RESULTS: For macular commotio retinae, 53 patients were identified, of whom 34 had adequate follow-up to determine final VA. The median presenting VA was 20/40; 25 patients (74%) recovered to ≥ 20/30. The median extent of visual recovery was 0.18 logarithm of the minimum angle of resolution (logMAR). For extramacular commotio retinae, 117 patients were identified, of whom 58 had adequate follow-up to determine final VA. The median presenting VA retinae was 20/30; 55 patients (95%) recovered to ≥ 20/30. The median extent of visual recovery was logMAR 0.076. There was 1 case of extramacular sclopetaria retinae. The 3 most common retinal locations of extramacular commotio retinae, in order of frequency, were inferotemporal (37%), temporal (17%), and superotemporal (17%); <5% of cases were in a nasal location. CONCLUSIONS: This is the first report on the prognosis of acute traumatic maculopathy and extramacular commotio retinae. After macular injury, 26% of patients were left with a VA of ≤ 20/30, although the proportion with visual impairment is higher than this because (1) a deterioration from 20/15 to 20/30 is significant to many patients; and (2) additional patients are visually impaired by symptomatic paracentral visual field defects despite a normal VA. Reduced VA after extramacular commotio retinae may represent occult macular injury or previously undiagnosed visual impairment in the affected eye. Extramacular commotio occurs mostly in an inferotemporal to temporal location, consistent with direct trauma to the sclera overlying the injured retina. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any of the materials discussed in this article.