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Sodium MRI has the potential to depict cartilage health accurately, but synovial fluid can influence the estimation of sodium parameters of cartilage. Therefore, this study aimed to reduce the impact of synovial fluid to render the quantitative compositional analyses of cartilage tissue technically more robust. Two dedicated protocols were applied for determining sodium <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi mathvariant="normal">T</mi><mn>1</mn></msub></mrow></semantics></math></inline-formula> and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msubsup><mi mathvariant="normal">T</mi><mn>2</mn><mo>*</mo></msubsup></mrow></semantics></math></inline-formula> relaxation times. For each protocol, data were acquired from 10 healthy volunteers and one patient with patellar cartilage damage. Data recorded with multiple repetition times for <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi mathvariant="normal">T</mi><mn>1</mn></msub></mrow></semantics></math></inline-formula> measurement and multi-echo data acquired with an additional inversion recovery pulse for <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msubsup><mi mathvariant="normal">T</mi><mn>2</mn><mo>*</mo></msubsup></mrow></semantics></math></inline-formula> measurement were analysed using biexponential models to differentiate longitudinal relaxation components of cartilage (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi mathvariant="normal">T</mi><mrow><mn>1</mn><mo>,</mo><mi>car</mi></mrow></msub></mrow></semantics></math></inline-formula>) and synovial fluid (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi mathvariant="normal">T</mi><mrow><mn>1</mn><mo>,</mo><mi>syn</mi></mrow></msub></mrow></semantics></math></inline-formula>), and short (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msubsup><mi mathvariant="normal">T</mi><mrow><mn>2</mn><mi mathvariant="normal">s</mi></mrow><mo>*</mo></msubsup></mrow></semantics></math></inline-formula>) from long (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msubsup><mi mathvariant="normal">T</mi><mrow><mn>2</mn><mi mathvariant="normal">l</mi></mrow><mo>*</mo></msubsup></mrow></semantics></math></inline-formula>) transversal relaxation components. Sodium relaxation times and concentration estimates in patellar cartilage were successfully determined: <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi mathvariant="normal">T</mi><mrow><mn>1</mn><mo>,</mo><mi>car</mi></mrow></msub></mrow></semantics></math></inline-formula> = 14.5 ± 0.7 ms; <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi mathvariant="normal">T</mi><mrow><mn>1</mn><mo>,</mo><mi>syn</mi></mrow></msub></mrow></semantics></math></inline-formula> = 37.9 ± 2.9 ms; c(<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi mathvariant="normal">T</mi><mn>1</mn></msub></mrow></semantics></math></inline-formula>-protocol) = 200 ± 48 mmol/L; <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msubsup><mi mathvariant="normal">T</mi><mrow><mn>2</mn><mi mathvariant="normal">s</mi></mrow><mo>*</mo></msubsup></mrow></semantics></math></inline-formula> = 0.4 ± 0.1 ms; <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msubsup><mi mathvariant="normal">T</mi><mrow><mn>2</mn><mi mathvariant="normal">l</mi></mrow><mo>*</mo></msubsup></mrow></semantics></math></inline-formula> = 12.6 ± 0.7 ms; c(<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msubsup><mi mathvariant="normal">T</mi><mn>2</mn><mo>*</mo></msubsup></mrow></semantics></math></inline-formula>-protocol) = 215 ± 44 mmol/L for healthy volunteers. In conclusion, a robust determination of sodium relaxation times is possible at a clinical field strength of 3T to quantify sodium concentrations, which might be a valuable tool to determine cartilage health.