Human Male Body Size Predicts Increased Knockout Power, Which Is Accurately Tracked by Conspecific Judgments of Male Dominance.

Humans have undergone a long evolutionary history of violent agonistic exchanges, which would have placed selective pressures on greater body size and the psychophysical systems that detect them. The present work showed that greater body size in humans predicted increased knockout power during combative contests (Study 1a-1b: total N = 5,866; Study 2: N = 44 openweight fights). In agonistic exchanges reflective of ancestral size asymmetries, heavier combatants were 200% more likely to win against their lighter counterparts because they were 200% more likely to knock them out (Study 2). Human dominance judgments (total N = 500 MTurkers) accurately tracked the frequency with which men (N = 516) knocked out similar-sized adversaries (Study 3). Humans were able to directly perceive a man's knockout power because they were attending to cues of a man's body size. Human dominance judgments-which are important across numerous psychological domains, including attractiveness, leadership, and legal decision-making-accurately predict the likelihood with which a potential mate, ally, or rival can incapacitate their adversaries.

"If I am alive, I am happy": Defining quality of care from the perspectives of key maternal and newborn health stakeholders in Papua New Guinea.

Quality maternal and newborn healthcare is essential to improve experiences and health outcomes for mothers and babies. In many low to middle income countries, such as Papua New Guinea, there are initiatives to increase antenatal care attendance and facility births. To develop and implement initiatives that are appropriate, relevant, and contextualised to a community, it is important to understand how quality of care is perceived and defined by different maternal and newborn healthcare stakeholders. The aim of this study was to understand how women, their partners, healthcare professionals, healthcare managers, and provincial health administrators in East New Britain, Papua New Guinea define quality of pregnancy, childbirth, and immediate postnatal care. An exploratory qualitative study underpinned by a partnership-defined quality approach was undertaken. In total, 42 participants from five different healthcare facilities in East New Britain, Papua New Guinea, were interviewed. These included women, partners, healthcare professionals, healthcare managers, and provincial health administrators. Interviews were analysed using thematic analysis, assisted by NVivo computer software. Four themes were identified aligning with the journey a woman takes throughout the health system. These included (I) Ensuring Access: Arriving at the health centre, (II) Experiencing Positive Care: What the staff do, (III) Having the Bare Minimum: Resources available to the service, and (IV) Meeting Expectations: Outcomes of care. Stakeholder groups had significant overlap in how quality of care was defined, however women and partners focussed more on elements relating to experience of care, while clinical stakeholders focussed on elements relating to provision of care. There is a gap in how stakeholders define quality maternal and newborn healthcare, and the quality of the care which is administered and received.

Impact of Distinct Anti-Androgen Exposures on the Plasma Metabolome in Feminizing Gender-Affirming Hormone Therapy.

CONTEXT: The plasma metabolome is a functional readout of metabolic activity and is associated with phenotypes exhibiting sexual dimorphism, such as cardiovascular disease. Sex hormones are thought to play a key role in driving sexual dimorphism. OBJECTIVE: Gender-affirming hormone therapy (GAHT) is a cornerstone of transgender care, but longitudinal changes in the plasma metabolome with feminizing GAHT have not been described. METHODS: Blood samples were collected at baseline and after three and six months of GAHT from transgender women (n = 53). Participants were randomized to different anti-androgens, cyproterone acetate or spironolactone. NMR-based metabolomics was used to measure 249 metabolic biomarkers in plasma. Additionally, we used metabolic biomarker data from an unrelated cohort of children and their parents (n = 3,748) to identify sex- and age-related metabolite patterns. RESULTS: We identified 43 metabolic biomarkers altered after six months in both anti-androgen groups, most belonging to the very low- or low-density lipoprotein subclasses, with all but one showing a decrease. We observed a cyproterone acetate-specific decrease in glutamine, glycine, and alanine levels. Notably, of the metabolic biomarkers exhibiting the most abundant 'sex- and age-related' pattern (higher in assigned female children and lower in assigned female adults, relative to assigned males), 80% were significantly lowered after GAHT, reflecting a shift toward the adult female profile. CONCLUSION: Our results suggest an anti-atherogenic signature in the plasma metabolome after the first six months of feminizing GAHT, with cyproterone acetate also reducing specific plasma amino acids. This study provides novel insight into the metabolic changes occurring across feminizing GAHT.

Effect of Feminizing Hormone Therapy on QTc Interval: A Secondary Analysis of a Randomized Clinical Trial.

This secondary analysis of a randomized clinical trial investigates the effect of spironolactone and cyproterone acetate hormone therapy on the QT interval corrected for heart rate among transgender women and nonbinary or transfeminine individuals.

A disrupted FOXP3 transcriptional signature underpins systemic regulatory T cell insufficiency in early pregnancy failure.

Regulatory T (Treg) cell defects are implicated in disorders of embryo implantation and placental development, but the origins of Treg cell dysfunction are unknown. Here, we comprehensively analyzed the phenotypes and transcriptional profile of peripheral blood Treg cells in individuals with early pregnancy failure (EPF). Compared to fertile subjects, EPF subjects had 32% fewer total Treg cells and 54% fewer CD45RA+CCR7+ naive Treg cells among CD4+ T cells, an altered Treg cell phenotype with reduced transcription factor FOXP3 and suppressive marker CTLA4 expression, and lower Treg:Th1 and Treg:Th17 ratios. RNA sequencing demonstrated an aberrant gene expression profile, with upregulation of pro-inflammatory genes including CSF2, IL4, IL17A, IL21, and IFNG in EPF Treg cells. In silico analysis revealed 25% of the Treg cell dysregulated genes are targets of FOXP3. We conclude that EPF is associated with systemic Treg cell defects arising due to disrupted FOXP3 transcriptional control and loss of lineage fidelity.

Disruption of gender-affirming health care, and COVID-19 illness, testing, and vaccination among trans Australians during the pandemic: a cross-sectional survey.

OBJECTIVES: To assess rates of disruption of gender-affirming health care, of coronavirus disease 2019 (COVID-19) illness, testing, and vaccination, and of discrimination in health care among Australian trans people during the COVID-19 pandemic. DESIGN, SETTING: Online cross-sectional survey (1-31 May 2022); respondents were participants recruited by snowball sampling for TRANSform, an Australian longitudinal survey-based trans health study, 1 May - 30 June 2020. PARTICIPANTS: People aged 16 years or older, currently living in Australia, and with a gender different to their sex recorded at birth. MAIN OUTCOME MEASURES: Proportions of respondents who reported disruptions to gender-affirming health care, COVID-19 illness, testing, and vaccination, and positive and negative experiences during health care. RESULTS: Of 875 people invited, 516 provided valid survey responses (59%). Their median age was 33 years (interquartile range, 26-45 years); 193 identified as women or trans women (37%), 185 as men or trans men (36%), and 138 as non-binary (27%). Of 448 respondents receiving gender-affirming hormone therapy, 230 (49%) reported disruptions to treatment during the pandemic; booked gender-affirming surgery had been cancelled or postponed for 37 of 85 respondents (44%). Trans-related discrimination during health care was reported by a larger proportion of participants than in a pre-pandemic survey (56% v 26%). COVID-19 was reported by 132 respondents (26%), of whom 49 reported health consequences three months or more after the acute illness (37%; estimated Australian rate: 5-10%). Three or more COVID-19 vaccine doses were reported by 448 participants (87%; Australian adult rate: 70%). CONCLUSIONS: High rates of COVID-19 vaccination among the trans people we surveyed may reflect the effectiveness of LGBTIQA+ community-controlled organisation vaccination programs and targeted health promotion. Training health care professionals in inclusive services for trans people could improve access to appropriate health care and reduce discrimination.

Ecological engineering of iron ore tailings into useable soils for sustainable rehabilitation.

Ecological engineering of soil formation in tailings is an emerging technology toward sustainable rehabilitation of iron (Fe) ore tailings landscapes worldwide, which requires the formation of well-organized and stable soil aggregates in finely textured tailings. Here, we demonstrate an approach using microbial and rhizosphere processes to progressively drive aggregate formation and development in Fe ore tailings. The aggregates were initially formed through the agglomeration of mineral particles by organic cements derived from microbial decomposition of exogenous organic matter. The aggregate stability was consolidated by colloidal nanosized Fe(III)-Si minerals formed during Fe-bearing primary mineral weathering driven by rhizosphere biogeochemical processes of pioneer plants. From these findings, we proposed a conceptual model for progressive aggregate structure development in the tailings with Fe(III)-Si rich cements as core nuclei. This renewable resource dependent eco-engineering approach opens a sustainable pathway to achieve resilient tailings rehabilitation without resorting to excavating natural soil resources.

The impact of the first three months of the COVID-19 pandemic on the Australian trans community.

Background: Trans and gender diverse individuals (people who identify with a gender different to what was presumed for them at birth) are one of the most medically and socially marginalized groups in our community. The COVID-19 pandemic may compound preexisting depression and thoughts of self-harm or suicide. Aim: We aimed to explore the impact of the COVID-19 pandemic on the Australian trans community. Methods: An online cross-sectional survey was conducted between 1st May 2020 and 30th June 2020, amidst strict Australia-wide social restrictions. Australian trans people aged ≥16 years were eligible to participate. Survey questions explored the impact of the COVID-19 pandemic on living situation, employment, financial situation, and healthcare. Logistic regression to assess negative impacts due to COVID-19 on depression and thoughts of self-harm or suicide (measured by Patient Health Questionnaire-9 (PHQ-9) are presented as odds ratios (95% confidence interval)). Results: Of 1019 participants, 49.6% reported experiencing financial strain, 22% had reduced working hours, and 22.4% were unemployed (three times the national rate). Concerningly, 61.1% experienced clinically significant symptoms of depression (Patient Health Questionnaire-9 score ≥10), considerably higher than pre-COVID rates for the trans community and over twice the national rate. Moreover, 49% reported thoughts of self-harm or suicide (over three times the national rate) which was more likely if a person experienced cancelation or postponement of gender-affirming surgery (OR 1.56 (1.04, 2.35)), financial strain (OR 1.80 (1.36, 2.38)), or felt unsafe or afraid in their household (OR 1.96 (1.23, 3.08)). Discussion: Given rates of clinically significant depression and thoughts of self-harm or suicide are far higher in trans people than the general population, specific strategies to improve mental health in the trans community during the COVID-19 pandemic must be made a priority for policymakers, researchers, and health service providers to prevent suicide.Supplemental data for this article is available online at https://doi.org/10.1080/26895269.2021.1890659.

Regulatory T cells are paramount effectors in progesterone regulation of embryo implantation and fetal growth.

Progesterone (P4) is essential for embryo implantation, but the extent to which the pro-gestational effects of P4 depend on the maternal immune compartment is unknown. Here, we investigate whether regulatory T cells (Treg cells) act to mediate luteal phase P4 effects on uterine receptivity in mice. P4 antagonist RU486 administered to mice on days 0.5 and 2.5 postcoitum to model luteal phase P4 deficiency caused fewer CD4+Foxp3+ Treg cells and impaired Treg functional competence, along with dysfunctional uterine vascular remodeling and perturbed placental development in midgestation. These effects were linked with fetal loss and fetal growth restriction, accompanied by a Th1/CD8-skewed T cell profile. Adoptive transfer at implantation of Treg cells - but not conventional T cells - alleviated fetal loss and fetal growth restriction by mitigating adverse effects of reduced P4 signaling on uterine blood vessel remodeling and placental structure and by restoring maternal T cell imbalance. These findings demonstrate an essential role for Treg cells in mediating P4 effects at implantation and indicate that Treg cells are a sensitive and critical effector mechanism through which P4 drives uterine receptivity to support robust placental development and fetal growth.

Virtual reality-based interventions for the rehabilitation of vestibular and balance impairments post-concussion: a scoping review.

BACKGROUND: Concussions and mild traumatic brain injuries are the most common causes of physical and cognitive disability worldwide. Concussion can result in post-injury vestibular and balance impairments that can present up to five years post initial concussion event, ultimately affecting many daily and functional activities. While current clinical treatment aims to reduce symptoms, the developing use of technology in everyday life has seen the emergence of virtual reality. Current literature has failed to identify substantial evidence regarding the use of virtual reality in rehabilitation. The primary aim of this scoping review is to identify, synthesise, and assess the quality of studies reporting on the effectiveness of virtual reality for the rehabilitation of vestibular and balance impairments post-concussion. Additionally, this review aims to summarise the volume of scientific literature and identify the knowledge gaps in current research pertaining to this topic. METHODS: A scoping review of six databases (PubMed, Embase, CINAHL, ProQuest, SportDiscus, Scopus) and a grey literature (Google Scholar) was conducted using three key concepts (virtual reality, vestibular symptoms, and post-concussion). Data was charted from studies and outcomes were categorised into one of three categories: (1) balance; (2) gait; or (3) functional outcome measures. Critical appraisal of each study was conducted using the Joanna Briggs Institute checklists. A critical appraisal of each outcome measure was also completed utilising a modified GRADE appraisal tool to summarise the quality of evidence. Effectiveness was assessed using calculations of change in performance and change per exposure time. RESULTS: Three randomised controlled trials, three quasi-experimental studies, three case studies, and one retrospective cohort study were ultimately included, using a thorough eligibility criteria. All studies were inclusive of different virtual reality interventions. The ten studies had a 10-year range and identified 19 different outcome measures. CONCLUSION: The findings from this review suggests that virtual reality is an effective tool for the rehabilitation of vestibular and balance impairments post-concussion. Current literature shows sufficient but low level of evidence, and more research is necessary to develop a quantitative standard and to better understand appropriate dosage of virtual reality intervention.

Pelvic Pain in Transgender People Using Testosterone Therapy.

Purpose: This descriptive study aimed to assess the characteristics of pelvic pain and explore predictive factors for pelvic pain in transgender (trans) individuals using testosterone therapy. Methods: An online cross-sectional survey was open between August 28, 2020, and December 31, 2020, to trans people presumed female at birth, using testosterone for gender affirmation, living in Australia, and >16 years of age. The survey explored characteristics of pelvic pain following initiation of testosterone therapy, type and length of testosterone therapy, menstruation history, and relevant sexual, gynecological, and mental health experiences. Logistic regression was applied to estimate the effect size of possible factors contributing to pain after starting testosterone. Results: Among 486 participants (median age = 27 years), 351 (72.2%)* reported experiencing pelvic pain following initiation of testosterone therapy, described most commonly as in the suprapubic region and as "cramping." Median duration of testosterone therapy was 32 months. Persistent menstruation, current or previous history of post-traumatic stress disorder, and experiences of pain with orgasm were associated with higher odds of pelvic pain after testosterone therapy. No association was observed with genital dryness, intrauterine device use, previous pregnancy, penetrative sexual activities, touching external genitalia, or known diagnoses of endometriosis, vulvodynia, vaginismus, depression, anxiety, or obesity. Conclusions: Pelvic pain is frequently reported in trans people following initiation of testosterone therapy. Given the association with persistent menstruation and orgasm, as well as the known androgen sensitivity of the pelvic floor musculature, further research into pelvic floor muscle dysfunction as a contributor is warranted.

The psychological sequelae of maxillofacial trauma: a scoping review of the literature.

Managing the physical sequelae of facial trauma is routine for the maxillofacial surgeon. However, managing the psychological consequences is more challenging. The often violent mechanism of injury, changes in appearance, altered self-perception, and self-confidence can significantly impact daily life. This review summarises the literature regarding post-traumatic stress disorder (PTSD) and facial trauma, highlighting evidence to guide clinical practice. PubMed and MEDLINE were searched for relevant keywords and MeSH headings. Articles between 2000-2022 were independently reviewed by two authors. Articles were excluded if the full text was not available in English, did not relate to facial trauma, or was not related to PTSD/psychological sequelae. A total of 211 articles were retrieved. The most common reasons for exclusion were papers not reporting psychological outcomes (n = 68) or not relating to facial trauma (n = 35). Articles were sub-categorised to enable evaluation of key themes. Categories included children and adolescents, cross sectional, longitudinal studies, and interventional studies. Whilst there were potential confounders such as socioeconomic factors, overall, patients who had experienced facial trauma (regardless of the mechanism of injury) had an increased risk of PTSD and anxiety/depression. PTSD following facial injury is increasingly recognised as an important issue. A robust evidence base is desirable to inform clinical practice and provide holistic care to often vulnerable patients. Identifying those at increased risk of negative psychological sequelae is essential. We have appraised the literature relevant to OMFS trauma clinicians.

Immune-Metabolic Interactions and T Cell Tolerance in Pregnancy.

Pregnancy depends on a state of maternal immune tolerance mediated by CD4+ regulatory T (Treg) cells. Uterine Treg cells release anti-inflammatory factors, inhibit effector immunity, and support adaptation of the uterine vasculature to facilitate placental development. Insufficient Treg cells or inadequate functional competence is implicated in infertility and recurrent miscarriage, as well as pregnancy complications preeclampsia, fetal growth restriction, and preterm birth, which stem from placental insufficiency. In this review we address an emerging area of interest in pregnancy immunology-the significance of metabolic status in regulating the Treg cell expansion required for maternal-fetal tolerance. We describe how hyperglycemia and insulin resistance affect T cell responses to suppress generation of Treg cells, summarize data that implicate a role for altered glucose metabolism in impaired maternal-fetal tolerance, and explore the prospect of targeting dysregulated metabolism to rebalance the adaptive immune response in women experiencing reproductive disorders.

Effect of Radiological Evidence of Kaplan Fiber Injury on the Clinical and Functional Outcomes After Acute Anterior Cruciate Ligament Reconstruction.

BACKGROUND: A paucity of information is available regarding the clinical outcomes of patients with radiological evidence of Kaplan fiber (KF) injury who undergo anterior cruciate ligament (ACL) reconstruction (ACLR). PURPOSE/HYPOTHESIS: The purpose was to compare clinical and functional outcomes in patients undergoing acute primary ACLR with and without magnetic resonance imaging (MRI) evidence of KF injury. The hypothesis was that there would be no difference in clinical or functional outcomes in patients with versus those without radiological evidence of KF injury. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: MRI analysis was conducted on patients in a longitudinal prospective study of ACL injury. Only patients who had an MRI scan and had undergone isolated primary ACLR within 60 days of injury were included. MRI was performed using standard knee protocols, and diagnostic criteria were applied to identify KF injury. A total of 32 patients with KF injury (mean age, 24.2 years; 21 male, 11 female) were identified and matched for sex, age, graft type, and preinjury activity with 90 patients who had intact KF. Patients were followed up at 12 months with KT-1000 arthrometer measurements of side-to-side difference in anterior knee laxity, single- and triple-hop limb symmetry index (LSI), Marx activity and International Knee Documentation Committee (IKDC) scores, and return to sport (RTS) rates at 12 months and 24 months. RESULTS: No differences were found in anterior knee laxity and single- and triple-hop LSI values between the KF-intact and KF-injured cohorts at 12 months. No differences in Marx and IKDC scores were found between the groups at 12 months and 2 years. The overall rate of RTS within 24 months was 75% (92/122), and 5 patients (2 KF-injured; 3 KF-intact) had a subsequent graft rupture. CONCLUSION: We found no difference in clinical or functional outcomes in patients with and without radiological evidence of KF injury who underwent acute primary ACLR. Based on these findings, the radiological presence of KF injury at the time of acute ACL injury should not be regarded as a risk factor for a negative prognosis after ACLR.

Regulatory T Cell Proportion and Phenotype Are Altered in Women Using Oral Contraception.

Regulatory T (Treg) cells are a specialized CD4+ T cell subpopulation that are essential for immune homeostasis, immune tolerance, and protection against autoimmunity. There is evidence that sex-steroid hormones estrogen and progesterone modulate Treg cell abundance and phenotype in women. Since natural oscillations in these hormones are modified by hormonal contraceptives, we examined whether oral contraception (OC) use impacts Treg cells and related T cell populations. T cells were analyzed by multiparameter flow cytometry in peripheral blood collected across the menstrual cycle from healthy women either using OC or without hormonal contraception and from age-matched men. Compared to naturally cycling women, women using OC had fewer Treg cells and an altered Treg cell phenotype. Notably, Treg cells exhibiting a strongly suppressive phenotype, defined by high FOXP3, CD25, Helios, HLADR, CTLA4, and Ki67, comprised a lower proportion of total Treg cells, particularly in the early- and mid-cycle phases. The changes were moderate compared to more substantial differences in Treg cells between women and men, wherein women had fewer Treg cells-especially of the effector memory Treg cell subset-associated with more T helper type 1 (Th1) cells and CD8+ T cells and lower Treg:Th1 cell and Treg:CD8+ T cell ratios than men. These findings imply that OC can modulate the number and phenotype of peripheral blood Treg cells and raise the possibility that Treg cells contribute to the physiological changes and altered disease susceptibility linked with OC use.

Zinc finger RNA binding protein 2 (ZFR2) is not required for male fertility in the mouse.

BACKGROUND: Thousands of genes are expressed during spermatogenesis and male infertility has a strong genetic component. Within this study, we focus on the role of Zfr2 in male fertility, a gene previously implicated in human male fertility. To date, very little is known about the role of ZFR2 in either humans or mice. To this end, the requirement for ZFR2 in male fertility was assessed using a knockout mouse model. RESULTS: Zfr2 was found to be expressed in the testes of both humans and mice. Deletion of Zfr2 was achieved via removal of exon 2 using CRISPR-Cas9 methods. The absence of Zfr2 did not result in a reduction in any fertility parameters assessed. Knockout males were capable of fostering litter sizes equal to wild type males, and there were no effects of Zfr2 knockout on sperm number or motility. We note Zfr2 knockout females were also fertile. CONCLUSIONS: The absence of Zfr2 alone is not sufficient to cause a reduction in male fertility in mice.

Spawning and maturity traits of coexisting Platycephalidae (Platycephalus caeruleopunctatus, Platycephalus grandispinis, Platycephalus richardsoni) from southeast Australia.

Examination of the spawning and maturity traits of coexisting Platycephalus caeruleopunctatus, Platycephalus grandispinis and Platycephalus richardsoni (Pisces: Platycephalidae) in coastal waters of southeastern Australia identified many commonalities. Each species was gonochoristic, reproductively active for a prolonged period each year, displayed asynchronous oocyte development with indeterminate fecundity and thus likely spawned multiple times throughout each spawning season. Males of all three species matured at smaller total lengths and younger ages than females, with skewed sex ratios reflecting divergent growth characteristics between sexes. Reproductive isolation among species is likely maintained through behavioural and morphological factors as well as species-specific depth-related separation of reproductively active individuals. General similarities in the reproductive strategies of each species and with other sympatric coastal teleosts suggest similar ecological adaptations to a variable coastal environment.

Immune determinants of endometrial receptivity: a biological perspective.

Immune cells are essential for endometrial receptivity to embryo implantation and early placental development. They exert tissue-remodeling and immune regulatory roles-acting to promote epithelial attachment competence, regulate the differentiation of decidual cells, remodel the uterine vasculature, control and resolve inflammatory activation, and suppress destructive immunity to paternally inherited alloantigens. From a biological perspective, the endometrial immune response exerts a form of "quality control"-it promotes implantation success when conditions are favorable but constrains receptivity when physiological circumstances are not ideal. Women with recurrent implantation failure and recurrent miscarriage may exhibit altered numbers or disturbed function of certain uterine immune cell populations-most notably uterine natural killer cells and regulatory T cells. Preclinical and animal studies indicate that deficiencies or aberrant activation states in these cells can be causal in the pathophysiological mechanisms of infertility. Immune cells are, therefore, targets for diagnostic evaluation and therapeutic intervention. However, current diagnostic tests are overly simplistic and have limited clinical utility. To be more informative, they need to account for the full complexity and reflect the range of perturbations that can occur in uterine immune cell phenotypes and networks. Moreover, safe and effective interventions to modulate these cells are in their infancy, and personalized approaches matched to specific diagnostic criteria will be needed. Here we summarize current biological understanding and identify knowledge gaps to be resolved before the promise of therapies to target the uterine immune response can be fully realized.

Quantitative assessment of bony orbital volume symmetry: CT analysis in the uninjured caucasian population.

There is a surprising lack of evidence documenting the volumetric symmetry of the bony orbit. This paper establishes reference values for orbital volume (OV) and symmetry in the 25 - 40 year old caucasian population. Secondarily, this paper sets a landmark for the tolerances in OV that can be expected when reconstructing the bony defects which may occur from trauma. A standardised method of quantitative OV measurement was developed using CT sinus examinations acquired for indications unrelated to orbital trauma. Sex, ethnicity, age, right and left OV were recorded. Data for 100 patients was obtained (50 male, 50 female). Mean left OV was 23.1cm3 and mean right OV was 23.3cm3. Left and right OV were strongly positively correlated (correlation coefficient: 0.96). Mean female OV was 21.6cm3 and mean male OV was 24.8cm3. On average, male OV is 3.2cm3 larger than female OV. The mean difference between left and right OV was 0.5cm3 in females and 0.6cm3 in males. The intra-class coefficient score between the two assessors was 0.973 (excellent). There is strong positive correlation between left and right OV in this study population. Previous work suggests that orbital volume loss less than 1cm3 would not lead to significant clinical symptoms of orbital fracture. When orbital reconstruction is undertaken, this study suggests that a volume symmetry difference of <0.5cm3 in females and <0.6cm3 in males would be consistent with the variation seen in the study population of uninjured caucasian 25-40 year olds and is therefore a reasonable goal of surgical management.