20.500.12556/RUL-166345 Ultrasound speckle tracking method based on gradient optical flow to quantify small longitudinal displacement, shear and longitudinal strain in peripheral nerves Objective: This study aimed to develop, validate and test the clinical feasibility of ultrasound (US) speckle tracking method based on gradient optical flow for quantifying small longitudinal displacements, shear and strain in peripheral nerves. Methods: The speckle tracking method was validated using seven thawed, fresh-frozen isolated cadaveric forearms. Longitudinal motion of the median nerve was captured using a high-frequency 22 MHz linear probe. An air bubble marker was inserted as a reference point for manual measurement comparison. The precision and accuracy of the method were assessed by comparing manual and automatic measurements. Clinical feasibility was tested on eight healthy subjects, measuring the longitudinal displacement of the median nerve during elbow extension and shoulder anteflexion. Results: The method demonstrated linearity, high precision and accuracy, particularly with a backtrace of five frames, reducing the displacement underestimation to 4%. In cadaveric models, the highest shear strain was observed at the nerve-tissue interfaces. In healthy subjects, the mean displacement of the median nerve was 3.3 ± 1.0 mm, with good inter-rater reliability (intraclass correlation coefficient = 0.87). Conclusion: The US speckle tracking method based on gradient optical flow effectively quantifies small longitudinal displacements and shear strain in peripheral nerves, with high precision and accuracy. However, the method could not detect longitudinal strain in nerves within the range of tested displacements. Future studies should investigate its applicability to smaller and deeper nerves and its usefulness in different pathological conditions. gradient optical flow high-resolution ultrasound peripheral nerve displacement shear strain quantification speckle tracking gradientni optični tok ultrazvok visoke ločljivosti premik perifernega živca kvantifikacija strižne deformacije pegasto sledenje true false true Angleški jezik Slovenski jezik Članek v reviji 2025-01-08 09:00:21 2025-01-08 09:00:27 2025-01-09 03:58:00 0000-00-00 00:00:00 2025 0 0 Str. 280-287 iss. 2 Vol. 51 2025 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 616-07 0301-5629 10.1016/j.ultrasmedbio.2024.10.002 214411267 1-s2.0-S0301562924003855-main.pdf 1-s2.0-S0301562924003855-main.pdf 1 9B448C7BA41E94D77B8B717878AEB2F5 a664e0240e2d29d6c4c26fd6e7a5b1fd3bc26dd18d4177da407619e31e1953fc a6a616b1-cd96-11ef-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=197889 https://www.sciencedirect.com/science/article/pii/S0301562924003855 0 9e3067cc-cd96-11ef-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=197888 https://www.umbjournal.org/article/S0301-5629(24)00385-5/fulltext 1 e9754820-cd95-11ef-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=197887 Medicinska fakulteta 0 0 0