====== Prominent vessel sign ======


The prominent vessel sign (PVS) on [[SWI]] refers to asymmetric multiple [[hypointense]] vessels in the area of [[cerebral ischemia]]
((Chen, C. Y., Chen, C. I., Tsai, F. Y., Tsai, P. H. & Chan, W. P. Prominent vessel sign on susceptibility-weighted imaging in acute stroke: prediction of infarct growth and clinical outcome. PLoS ONE 10, e0131118 (2015).))
((Liang, J. et al. Susceptibility-weighted imaging in post-treatment evaluation in the early stage in patients with [[acute ischemic stroke]]. J. Int. Med. Res. 47, 196–205 (2019).)).

It is widely accepted that the PVS is caused by the increased [[oxygen extraction fraction]]. In [[acute ischemic stroke]], when [[blood flow]] is significantly decreased, the oxygen extraction fraction of the involved [[brain tissue]] is elevated, leading to an increase in [[deoxyhemoglobin]] in veins and capillaries. Deoxyhemoglobin is a paramagnetic substance with high magnetic susceptibility, which shows the PVS on SWI
((Hermier, M. & Nighoghossian, N. Contribution of susceptibility-weighted imaging to acute stroke assessment. Stroke 35, 1989–1994 (2004).))
((Geisler, B. S. et al. Blood-oxygen-level-dependent MRI allows metabolic description of tissue at risk in acute stroke patients. Stroke 37, 1778–1784 (2006).))
((Xia, S. et al. Decreased oxygen saturation in asymmetrically prominent cortical veins in patients with cerebral ischemic stroke. Magn. Reson. Imaging 32, 1272–1276 (2014).))
((Kesavadas, C., Santhosh, K. & Thomas, B. Susceptibility weighted imaging in cerebral hypoperfusion-can we predict increased oxygen extraction fraction?. Neuroradiology 52, 1047–1054 (2010).))
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To determine the value of [[susceptibility weighted imaging]] ([[SWI]]) for collateral estimation and for predicting [[functional outcome]]s after [[acute ischemic stroke]]. To identify independent [[predictor]]s of favorable functional outcomes, age, sex, [[risk factor]]s, baseline National Institutes of Health Stroke Scale ([[NIHSS]]) score, baseline diffusion-weighted imaging ([[DWI]]) lesion [[volume]], site of steno-occlusion, SWI collateral grade, mode of treatment, and successful [[reperfusion]] were evaluated by multiple [[logistic regression]] analyses. A total of 152 participants were evaluated. A younger age (adjusted [[odds ratio]] (aOR), 0.42; 95% [[confidence interval]] (CI) 0.34 to 0.77; P < 0.001), a lower baseline NIHSS score (aOR 0.90; 95% CI 0.82 to 0.98; P = 0.02), a smaller baseline DWI lesion volume (aOR 0.83; 95% CI 0.73 to 0.96; P = 0.01), an intermediate collateral grade (aOR 9.49; 95% CI 1.36 to 66.38; P = 0.02), a good collateral grade (aOR 6.22; 95% CI 1.16 to 33.24; P = 0.03), and successful reperfusion (aOR 5.84; 95% CI 2.08 to 16.42; P = 0.001) were independently associated with a favorable functional outcome. There was a linear association between the SWI collateral grades and functional outcome (P = 0.008). Collateral estimation using the [[prominent vessel sign]] on SWI is clinically reliable, as it has prognostic value
((Lee HJ, Roh HG, Lee SB, Jeon YS, Park JJ, Lee TJ, Jung YJ, Choi JW, Chun YI, Ki HJ, Cho J, Lee JS, Kim HJ. Collateral estimation by susceptibility-weighted imaging and prediction of functional outcomes after acute anterior circulation ischemic stroke. Sci Rep. 2021 Nov 1;11(1):21370. doi: 10.1038/s41598-021-00775-9. PMID: 34725373.)).