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BACKGROUND: Breast implants may increase breast skin tension and interact with surrounding tissues to alter breast position and motion during dynamic activity. Reducing implant mass and changing implant location (submuscular/subglandular) may also affect breast kinematics and the subsequent loads on breast structures. OBJECTIVES: The aim of this pilot study was to describe the kinematics of breasts augmented with reduced-mass implants during standing, walking, and running, compared with natural breasts, and to provide insight into how implant location (submuscular/subglandular) alters breast kinematics. METHODS: Two breast augmentation participants (12-15 months postsurgery: 32AA presurgery, anatomical submuscular 255 cc B-Lite reduced-mass implant; 32A presurgery, anatomical subglandular 285 cc B-Lite reduced-mass implant) and 2 natural-breasted participants of similar breast size and anthropometrics were recruited. Nipple and torso positional data were recorded with electromagnetic sensors during standing, walking, and running. Nipple kinematics relative to the torso were calculated. RESULTS: The B-Lite participants both displayed greater nipple projection and elevation during standing and a 50% reduction in nipple acceleration during walking, when compared with their natural counterparts. During running, the B-Lite subglandular participant displayed decreased nipple kinematics compared with her natural counterpart and lower nipple kinematics compared with the B-Lite submuscular participant during walking and running. CONCLUSIONS: A combination of implant location (subglandular) and reduced mass minimized nipple kinematics during running. Reducing nipple kinematics during dynamic activity may decrease the loading on breast structures, helping to decrease ptosis and increase the longevity of procedure outcomes.
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Implantación de Mama , Implantes de Mama , Mamoplastia , Fenómenos Biomecánicos , Implantación de Mama/efectos adversos , Femenino , Humanos , Proyectos PilotoRESUMEN
Chlorpyrifos (CPF) and CPF-oxon (CPO) are known to inhibit neurite outgrowth but little is known about their ability to induce neurite retraction in differentiating neuronal cells. The aims of this study were to determine the ability of these compounds to destabilize neurites and to identify the key molecular events involved. N2a cells were induced to differentiate for 20h before exposure to CPF or CPO for 2-8h. Fixed cell monolayers labeled with carboxyfluorescein succinimidyl ester or immunofluorescently stained with antibodies to tubulin (B512) or phosphorylated neurofilament heavy chain (Ta51) showed time- and concentration-dependent reductions in numbers and length of axon-like processes compared to the control, respectively, retraction of neurites being observed within 2h of exposure by live cell imaging. Neurofilament disruption was also observed in treated cells stained by indirect immunofluorescence with anti-phosphorylated neurofilament heavy chain (NFH) monoclonal antibody SMI34, while the microtubule network was unaffected. Western blotting analysis revealed transiently increased levels of reactivity of Ta51 after 2h exposure and reduced levels of reactivity of the same antibody following 8h treatment with both compounds, whereas reactivity with antibodies to anti-total NFH or anti-tubulin was not affected. The alteration in NFH phosphorylation at 2h exposure was associated with increased activation of extracellular signal-regulated protein kinase ERK 1/2. However, increased levels of phosphatase activity were observed following 8h exposure. These findings suggest for the first time that organophosphorothionate pesticide-induced neurite retraction in N2a cells is associated with transient increases in NFH phosphorylation and ERK1/2 activation.
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Cloropirifos/toxicidad , Insecticidas/toxicidad , Sistema de Señalización de MAP Quinasas , Neuritas/efectos de los fármacos , Proteínas de Neurofilamentos/metabolismo , Animales , Diferenciación Celular , Línea Celular Tumoral , Ratones , FosforilaciónRESUMEN
Breast asymmetry is common in females, despite a similar driving force; dynamic activity may result in asymmetrical breast motion. This preliminary study investigated how breast categorisation (left/right or dominant/non-dominant) may affect breast support recommendations and its relationship with breast pain. Ten females ran on a treadmill at 10 kph in three breast supports (no bra, everyday bra, sports bra). Five reflective markers on the thorax and nipples were tracked using infrared cameras (200 Hz) during five running gait cycles in each breast support. Multiplanar displacements of both breasts were calculated relative to the thorax. Although the maximum individual participant difference was 2.4 cm (mediolaterally) between the left and right breast, no left/right differences were found in any direction or support condition. Notably, correlations between breast pain and anterioposterior breast displacement were stronger with the left breast (r = 0.614) and moderate with the right breast (r = 0.456). Following participant categorisation according to the greatest magnitude of superioinferior breast displacement (dominant breast), results showed significant differences in displacement for all directions across different breast supports. When using breast kinematic data to examine relationships with breast pain or to recommend breast support requirements, data on both breasts should be collected.
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Mama/fisiología , Carrera/fisiología , Vestuario , Femenino , Marcha , Humanos , Mastodinia/fisiopatología , Movimiento , Adulto JovenRESUMEN
Recommendations for breast support, dynamic breast pain assessment, and implications for sports performance have been made within breast biomechanics research; however, these studies have been based upon short exercise protocols (2-5 min). The aim of this study was to investigate the effect of breast support on multiplanar breast kinematics over a 5-kilometre run. Ten female participants (34D or 32DD) conducted two 5-kilometre runs, in a low and high breast support. Relative multiplanar breast kinematics were averaged over five gait cycles at six intervals of a 5-kilometre run. Increases in multiplanar breast kinematics were reported from the start to the end of the run, with the greatest rate of increase in breast kinematics reported within the first two kilometres of running. The greatest relative increases in breast range of motion (34%), velocity (33%), and acceleration (41%) were reported in the superioinferior direction at the fifth kilometre (33 min of running) in the high breast support. Key findings suggest that the run distance, and therefore run duration, employed for both fundamental research and product validation protocols should be carefully considered and it is suggested that running protocols for assessing breast biomechanics should exceed 7 min.
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Mama/fisiología , Vestuario , Carrera/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Movimiento/fisiología , Factores de Tiempo , Adulto JovenRESUMEN
The relationship between inappropriate breast support and upper-extremity kinematics for female runners is unclear. The purpose of this study was to investigate the effect of breast support and breast pain on upper-extremity kinematics during running. Eleven female recreational runners with larger breasts (UK D and E cup) completed a 7 min 20 s treadmill run (2.58 m · s(-1)) in a high and low breast support condition. Multi-planar breast and upper-extremity kinematic data were captured in each breast support condition by eight infrared cameras for 30 s towards the end of the run. Breast pain was rated at the end of each treadmill run using a numeric analogue scale. The high support bra reduced breast kinematics and decreased breast pain (P < 0.05). Upper-extremity kinematics did not differ between breast support conditions (P > 0.05), although some moderate positive correlations were found between thorax range of motion and breast kinematics (r = 0.54 to 0.73). Thorax and arm kinematics do not appear to be influenced by breast support level in female runners with large breasts. A high support bra that offers good multi-planar breast support is recommended for female runners with larger breasts to reduce breast pain.
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Mama/anatomía & histología , Mama/fisiología , Vestuario , Mastodinia/prevención & control , Carrera/fisiología , Extremidad Superior/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Movimiento , Torso/fisiologíaRESUMEN
Breast displacement has been investigated in various activities to inform bra design, with the goal of minimising movement; however, breast motion during swimming has yet to be considered. The aim was to investigate trunk and breast kinematics whilst wearing varying levels of breast support during two swimming strokes. Six larger-breasted females swam front crawl and breaststroke (in a swimming flume), in three breast support conditions while three video cameras recorded the motion of the trunk and right breast. Trunk and relative breast kinematics were calculated. Greater breast displacement occurred mediolaterally in the swimsuit condition (7.8, s = 1.5 cm) during front crawl and superioinferiorly in the bare-breasted condition (3.7, s = 1.6 cm) during breaststroke, with the sports bra significantly reducing breast displacements. During front crawl, the greatest trunk roll occurred in the sports bra condition (43.1, s = 8.3°) and during breaststroke greater trunk extension occurred in the swimsuit condition (55.4, s = 5.0°); however, no differences were found in trunk kinematics between the three breast support conditions. Results suggest that the swimsuit was ineffective as a means of additional support for larger-breasted women during swimming; incorporating design features of sports bras into swimsuits may improve the breast support provided.
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Mama/fisiología , Vestuario , Natación/fisiología , Torso/fisiología , Adulto , Fenómenos Biomecánicos , Mama/anatomía & histología , Femenino , Humanos , MovimientoRESUMEN
More and more studies are emerging reporting breast kinematics. These studies rarely present effect sizes, power, and variance in the data. Important inferences are drawn from these data, including applications to product design, breast pain assessment, sports performance effects, and more. The aim of the study was to explore the within-participant variance in breast kinematic data during a 5 km run. Multiplanar breast kinematics and within-participant variance, defined by the coefficient of variation, for 10 female participants wearing a low and high level breast support were calculated during a 5 km run. Greater within-participant variance was reported in the high level (mean=15%) breast support compared with the low level (mean=12%). Within-participant variance in breast kinematics did not change over the 5 km run. Differences in the magnitude of within-participant variance in breast kinematics were reported between directions of breast movement, with greater levels in the anteroposterior direction compared with mediolateral and vertical. It is important for the progression of this research area that the presence and sources of within-participant variance in breast kinematics are quantified and acknowledged, ensuring that the margin for meaningful differences can be reported.
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Mama/fisiología , Vestuario , Carrera/fisiología , Fenómenos Biomecánicos , Prueba de Esfuerzo , Femenino , Humanos , Adulto JovenRESUMEN
Lead (Pb) is a toxic nonessential metal, known mainly for causing poisoning of humans and wild birds. However, little is known about Pb exposure and its associated health effects in wild mammals. We conducted a global systematic literature review to identify peer-reviewed studies published on Pb exposure in wild mammalian species and the health effects they identified. In total, 183 studies, conducted in 35 countries and published over 62 yr (1961-2022), were included in the review. Only 6% (11/183) of the studies were conducted in developing countries. Although 153 mammalian species were studied, most studies focused on species that are easy to access (i.e., hunted species and small mammals that are easy to trap). Therefore, carnivores and scavengers were less frequently studied than herbivores and omnivores. Despite all studies reporting Pb concentrations, only 45 (25%) studies investigated health effects and, of these 45 studies, only 28 (62%) found any health effect in 57 species. All health effects were negative and ranged from subclinical effects to fatality. Methodologies of Pb sampling and quantification and reporting of results varied widely across the studies, making both Pb concentrations and health effects difficult to compare and evaluate. Thus, there is a need for more research on Pb exposure and its health effects on wild mammals, especially as carnivores and scavengers could be used as sentinels for ecosystem health.
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Ecosistema , Plomo , Humanos , Animales , Plomo/toxicidad , Aves , Mamíferos , Animales SalvajesRESUMEN
This study aimed to use a musculoskeletal model to predict changes in spinal moments following simulated breast surgery. A female full body musculoskeletal model with a fully articulated thoracolumbar spine and independent moveable breast segments was customised for this study. Key findings suggest that the simulated removal of breast tissue (750 g to 1501 g) can reduce the magnitude of lumbar spine extensor moments by >0.05 Nm/kg during walking and jogging. A customised female whole-body musculoskeletal model is capable of providing a first approximation of changes in spinal loading following simulated breast surgery.
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Retained foreign bodies in small bowel diverticula are a rare occurrence. Batteries and battery containing products can cause bowel perforation, and when retained in diverticula, retrieval methods may need to be considered. We present a novel case of a hearing aid powered by lithium battery getting stuck in a jejunal diverticulum, and outline an approach to retrieval.
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Stepping between static and moving surfaces presents a locomotor challenge associated with increased injury frequency and severity in older adults. The current study evaluates younger and older adults' behaviours when overcoming challenges sampling moving walkway and escalator environments. Twelve younger adults (18-40 years, Male = 8) and 15 older adults (60-81 years, Male = 5) were examined using an integration of optoelectronic motion capture and mobile eye-tracking. Participants were investigated approaching and stepping onto a flat conveyor belt (static or moving; with or without surface (demarcation) lines). Specifically, the four conditions were: (i) static surface without demarcation lines; (ii) static surface with demarcation lines; (iii) moving surface without demarcation lines; and (iv) moving surface with demarcation lines. A two (age group) x two (surface-condition) x two (demarcation-condition) linear mixed-model revealed no main or interaction effects (p > .05) for perturbation magnitude, indicating participants maintained successful locomotion. However, different adaptive behaviours were identified between conditions with moving and accuracy demands (e.g., moving surfaces increased step length, demarcations reduced step length). Between subject effects identified differences between age groups. Older adults utilised different behaviours, such as earlier gaze transfer from the final approach walkway step location. Overall, the current study suggests that adaptive behaviours emerge relative to the environment's specific demands and the individual's action capabilities.
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Locomoción , Caminata , Humanos , Masculino , AncianoRESUMEN
Background: The food industry is responding to a rising demand for plant-based foods by developing and marketing an ever-wider range of vegan and vegetarian products under the banner of "plant-based." Understanding the nutritional properties of these products is critical. Objectives: To assess the number, meal type, and nutritional content of products marketed as plant-based (MaPB) from the perspective of the consumer across multiple sectors in the United States, United Kingdom, and Canada. Methods: An online search for products MaPB was performed across supermarkets, restaurants, food manufacturers, and plant-based meal delivery companies in the United Kingdom, the United States, and Canada using the terms: "vegan," "vegetarian," and "plant-based." Online nutrition data were extracted, and whole meals that comprised >50% of ingredients such as fruits, vegetables, legumes, nuts, and seeds were identified. The nutritional content of dishes MaPB in restaurants was also directly compared with meat-containing dishes. Results: Further, 3488 unique products were identified, of which 962 were whole meals and 1137 were a replacement for the main protein component in a meal, including 771 meat alternatives. Across all sectors, 45% of whole meals had >15-g protein, 70% had <10% kcal from saturated fat; 29% had >10-g fiber per meal, and 86% had <1000 mg sodium. At restaurants, 1507 meat-containing dishes were identified and compared with 191 vegetarian and 81 vegan dishes. The meat-containing dishes were higher in protein [35.4 g (24.0-51.4)] compared with vegetarian [19.0 g (13.0-26.1)] and vegan [16.2 g (10.5-23.2) dishes (P < 0.001)]. The vegan dishes were low in saturated fat and sodium (SFA: 6.3 g ± 6.4, Sodium: 800 mg (545.0-1410.0) compared with both meat [SFA: 11.6 g ± 10.0; Sodium: 1280 mg (820.0-1952.0)] and vegetarian [SFA: 9.4 g ± 7.6; Sodium: 1011 mg (603.0-1560.0)] options (P < 0.001 for all comparisons). Conclusions: Products MaPB tend to have lower concentrations of saturated fat and sodium than their meat-containing counterparts, but improvements are needed to optimize their nutritional composition.
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Improving the accuracy and enabling traceable measurements of volume, flow, and pressure in existing drug delivery devices and in-line sensors operating at very low flow rates is essential in several fields of activities and specially in medical applications. This can only be achieved through the development of new calibrationmethods and by expanding the existing metrological infrastructure to perform micro-flow and nano-flow measurements. In this paper, we will investigate new traceable techniques for measuring flow rate, from 5 nL/min to 1,500 nL/min and present the results of an inter-comparison between nine laboratories for the calibration of two different flow meters and a syringe pump.
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Sistemas de Liberación de Medicamentos , Flujómetros , CalibraciónAsunto(s)
Densidad de la Mama , Neoplasias de la Mama/diagnóstico por imagen , Mamografía/normas , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Modelos Teóricos , Valores de Referencia , Estudios Retrospectivos , Adulto JovenRESUMEN
Integrating mobile eye tracking and optoelectronic motion capture enables point of gaze to be expressed within the laboratory co-ordinate system and presents a method not commonly applied during research examining dynamic behaviors, such as locomotion. This paper examines the quality of gaze data collected through the integration. Based on research suggesting increased viewing distances are associated with reduced data quality; the accuracy and precision of gaze data as participants (N = 11) viewed floor-based targets at distances of 1-6â m was investigated. A mean accuracy of 2.55 ± 1.12° was identified, however, accuracy and precision measures (relative to targets) were significantly (p < .05) reduced at greater viewing distances. We then consider if signal processing techniques may improve accuracy and precision, and overcome issues associated with missing data. A 4th-order Butterworth lowpass filter with cut-off frequencies determined via autocorrelation did not significantly improve data quality, however, interpolation via Quintic spline was sufficient to overcome gaps of up to 0.1â s. We conclude the integration of gaze and motion capture presents a viable methodology in the study of human behavior and presents advantages for data collection, treatment, and analysis. We provide considerations for the collection, analysis, and treatment of gaze data that may help inform future methodological decisions.
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BACKGROUND: This study aimed to identify the predictor variables which account for neutral breast position variance using a full independent variable dataset (the gravity-loaded breast position, age and anthropometrics, and magnetic resonance imaging breast composition data), and a simplified independent variable dataset (magnetic resonance imaging breast composition data excluded). METHODS: Breast position (three-dimensional neutral and static gravity-loaded), age, anthropometrics and magnetic resonance imaging breast composition data were collected for 80 females (bra size 32A to 38D). Correlations between the neutral breast position and the gravity-loaded breast position, age, anthropometrics, and magnetic resonance imaging breast composition data were assessed. Multiple linear and multivariate multiple regression models were utilised to predict neutral breast positions, with mean absolute differences and root mean square error comparing observed and predicted neutral breast positions. FINDINGS: Breast volume was the only breast composition variable to contribute as a predictor of the neutral breast position. While ≥69% of the variance in the anteroposterior and mediolateral neutral breast positions were accounted for utilising the gravity-loaded breast position, multivariate multiple regression modelling resulted in mean absolute differences >5 mm. INTERPRETATION: Due to the marginal contribution of breast composition data, a full independent variable dataset may be unnecessary for this application. Additionally, the gravity-loaded breast position, age, anthropometrics, and breast composition data do not successfully predict the neutral breast position. Incorporation of the neutral breast position into breast support garments may enhance bra development. However, further identification of variables which predict the neutral breast position is required.
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Mama , Gravitación , Mama/diagnóstico por imagen , Femenino , HumanosRESUMEN
The acanthocephalan parasite Polymorphus minutus induces both physiological and behavioural effects in its intermediate host, Gammarus pulex. The net effect of parasite infection is to increase the likelihood of transmission to the definitive host. Osmoregulation is an energetically expensive mechanism that allows G. pulex to survive in dilute media. Any factor influencing osmoregulation is thus likely to affect the allocation of resources to other areas. This study investigated whether P. minutus infection alters sodium regulation in G. pulex. Haemolymph sodium concentration, water permeability and sodium fluxes were measured over the salinity acclimation range of G. pulex. Water permeability was unaltered by either acclimation salinity or parasite infection. Acclimation to 12 significantly raised the haemolymph sodium concentration, reduced the sodium influx, and increased the sodium efflux, to the same extent in both uninfected and infected G. pulex. However, parasite infection induced a significant increase in haemolymph sodium concentration in G. pulex acclimated to 6, which was not observed in uninfected G. pulex acclimated to the same salinity. Also, both sodium influx and sodium efflux were significantly lower in parasitized G. pulex acclimated to 6, when compared to uninfected G. pulex acclimated to the same salinity. It was concluded that the parasite induced disturbances to sodium regulation in G. pulex acclimated to 6 were a functional consequence of the manipulative strategy employed to alter behaviour, rather than a primary target.
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Anfípodos/metabolismo , Agua Dulce , Enfermedades Parasitarias/sangre , Sodio/sangre , Anfípodos/parasitología , Animales , Hemolinfa/metabolismoRESUMEN
BACKGROUND: Poor standing posture has been reported in women with larger breasts, increasing the risk of back pain. Whilst breast reduction surgery can improve posture, conservative measures such as special bras may offer short or long-term relief of symptoms without surgical intervention. RESEARCH QUESTION: This study aimed to utilise a multi-study intervention to investigate the short and long-term kinematic effects of wearing a posture bra. METHODS: Study one utilised biomechanics and physiotherapy expertise to modify the design of a prototype bra to improve posture and breast kinematics; resulting in a second-generation posture bra. To test this bra, 24 females were randomly assigned to control and intervention groups. The control group wore their everyday bra; the intervention group wore the generation 2 posture bra in place of their everyday bra for three months. Pre and post intervention, posture (spine curvature, scapula position, whole body alignment) and breast kinematics were assessed during sitting, standing and walking. Short-term effects of the posture bra were compared to an everyday bra and no bra (study two), whilst the long-term effects were compared using the no bra condition (study three). RESULTS: Biomechanical intervention improved posture and breast kinematics in a prototype posture bra resulting in a second-generation prototype. Pre-intervention, the generation 2 posture bra significantly improved scapula retraction by 6° during both sitting and standing, but also increased deviation of whole body alignment compared to everyday bra and no bra conditions. During walking the posture bra reduced breast motion by 17 % compared to the everyday bra. Following the three-month wearer intervention, scapula depression significantly improved in the intervention group. SIGNIFICANCE: A biomechanically informed posture bra was able to effectively support the breasts and improve scapula position without compromising spinal curvature, reducing the risk of musculoskeletal pain associated with poor posture.
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Fenómenos Biomecánicos/fisiología , Mama/anomalías , Mama/crecimiento & desarrollo , Hipertrofia/terapia , Equilibrio Postural/fisiología , Posición de Pie , Adulto , Femenino , Humanos , Adulto JovenRESUMEN
This study aimed to investigate: (1) the prevalence and magnitude of breast movement asymmetry, (2) the interaction between static and dynamic breast asymmetry and (3) the influence of sports bras on breast asymmetry during running. Position data were collected from 167 females whilst treadmill running and then a sub-group of 12 participants in different bra conditions. Breast movement asymmetry existed in 89% of participants, with resultant static breast position asymmetry larger in participants displaying dynamic asymmetry. Asymmetry was most commonly caused (60% to 75%) by greater movement of the left breast. No significant relationships were found between asymmetry and bra size or breast pain. Sports bras reduced asymmetry prevalence from 75% to 33% of participants in the antero-posterior direction but only from 75% to 67% of participants in the infero-superior direction. The magnitude of range-of-motion asymmetry reduced from 67 mm with no bra to between 6 and 64 mm in-bra in the infero-superior direction, with the best performing bra incorporating encapsulating cups and adjustable straps and underband. It is recommended that sports bras allow underband and strap adjustment to facilitate individual breast support and that asymmetry is considered when designing and fitting bras, which could utilise resultant asymmetry measured statically.
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Mama/fisiología , Vestuario , Diseño de Equipo , Mastodinia/prevención & control , Carrera/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Adulto JovenRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) is responsible for 1% of deaths worldwide, and the incidence continues to increase. Despite surveillance programs, 70% of HCC patients are not suitable for curative options at diagnosis, and therefore, non-curative treatments are essential to modern clinical practice. There are many novel treatments, though their roles are not well defined. This study aimed to contrast Selective Internal Radiation Therapy (SIRT) and Drug Eluting Bead Transarterial Chemoembolisation (DEB-TACE) to further define their roles. METHODS: This was a retrospective multicentre cohort study. Factors included for analysis were type of HCC treatment, number of lesions, lesion size, multiple disease severity scores, cirrhosis and vascular invasion. The primary endpoint was transplant-free survival. RESULTS: Transplant-free survival was similar between the two cohorts (p = 0.654), despite a variation in median lesion size, SIRT: 54.5 mm, DEB-TACE: 34 mm (p ≤ 0.001). A univariate Cox proportional hazard model utilising treatment modality as the covariate showed no significant difference in survival (DEB-TACE HR 1.4 (95%CI 0.85-2.15 p = 0.207). The size of the largest lesion was the best predictor of 3-year survival (p = 0.035). Lesion size was inversely associated with survival (HR 1.01 (95%CI 1-1.02, p = 0.025)) on multivariate analysis. CONCLUSION: This study is the first to catalogue the experience of using SIRT in HCC in a real-world Australian population. It has demonstrated no difference in survival outcomes between DEB-TACE and SIRT. Further, it has shown SIRT to be a reasonable alternative to DEB-TACE especially in larger lesions and has demonstrated that DEB-TACE has a role in select patients with advanced disease.