Helen DeJong1, Steven Abbott2, Marilyn Zelesco2, Katrina Spilsbury3, Melanie Ziman4, Brendan F Kennedy5, Lisa Martin6, Fiona M Wood7. 1. Perth Scar and Pain Clinic, 2/5 Norfolk Street, Fremantle, Western Australia 6160, Australia; School of Medical and Health Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia; BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre Nedlands and Centre for Medical Research, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia; Fiona Wood Foundation, Fiona Stanley Hospital, 11 Robin Warren Dr, Murdoch, Western Australian 6150, Australia. Electronic address: info@perthspc.com.au. 2. Department of Medical Imaging, Fiona Stanley Hospital, 11 Robin Warren Dr, Murdoch, Western Australian, 6150, Australia. 3. Institute for Health Research, University of Notre Dame Australia, Fremantle, Western Australia, Australia. 4. School of Medical and Health Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia; School of Biomedical Science, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia. 5. BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre Nedlands and Centre for Medical Research, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia; Department of Electrical, Electronic and Computer Engineering, School of Engineering, The University of Western Australia, 35 Stirling Hwy, Crawley, 6009, Western Australia, Australia; Australian Research Council Centre for Personalised Therapeutics Technologies, Australia. 6. Fiona Wood Foundation, Fiona Stanley Hospital, 11 Robin Warren Dr, Murdoch, Western Australian 6150, Australia. 7. Fiona Wood Foundation, Fiona Stanley Hospital, 11 Robin Warren Dr, Murdoch, Western Australian 6150, Australia; Burn Injury Research Unit, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia; Burn Service of Western Australia, Fiona Stanley Hospital, 11 Robin Warren Dr, Murdoch, Western Australian 6150, Australia.
Abstract
Shear-wave elastography (SWE) is an ultrasound based technology that can provide reliable measurements (velocity) of scar stiffness. The aim of this research was to evaluate the concurrent validity of using both the measured velocity and the calculated difference in velocity between scars and matched controls, in addition to evaluating potential patient factors that may influence the interpretation of the measurements. METHODS: A cross-sectional study of 32 participants, with 48 burn scars and 48 matched contralateral control sites were evaluated with SWE, the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scale (POSAS) tactile sub-scores. RESULTS: Spearman's rho demonstrated high correlations (r > 0.7) between the measured scar velocity and both the POSAS and VSS pliability sub-scores, whereas moderate correlations (r > 0.6) were found with the calculated difference in velocity. Regression analysis indicated that the association of increased velocity in scars, varied by length of time after burn injury and gender. Body location and Fitzpatrick skin type also demonstrated significant associations with velocity, whereas age did not. CONCLUSION: SWE shows potential as a novel tool to quantify burn scar stiffness, however patient factors need to be considered when interpreting results. Further research is recommended on a larger variety of scars to support the findings.
Shear-wave elastography (SWE) is an ultrasound based technology that can provide reliable measurements (velocity) of scar stiffness. The aim of this research was to evaluate the concurrent validity of using both the measured velocity and the calculated difference in velocity between scars and matched controls, in addition to evaluating potential patient factors that may influence the interpretation of the measurements. METHODS: A cross-sectional study of 32 participants, with 48 burn scars and 48 matched contralateral control sites were evaluated with SWE, the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scale (POSAS) tactile sub-scores. RESULTS: Spearman's rho demonstrated high correlations (r > 0.7) between the measured scar velocity and both the POSAS and VSS pliability sub-scores, whereas moderate correlations (r > 0.6) were found with the calculated difference in velocity. Regression analysis indicated that the association of increased velocity in scars, varied by length of time after burn injury and gender. Body location and Fitzpatrick skin type also demonstrated significant associations with velocity, whereas age did not. CONCLUSION: SWE shows potential as a novel tool to quantify burn scar stiffness, however patient factors need to be considered when interpreting results. Further research is recommended on a larger variety of scars to support the findings.