TY - JOUR A1 - Juratli, Mazen A. A1 - Menyaev, Yulian A. A1 - Sarimollaoglu, Mustafa A1 - Siegel, Eric R. A1 - Nedosekin, Dmitry A. A1 - Suen, James Y. A1 - Melerzanov, Alexander V. A1 - Juratli, Tareq A. A1 - Galanzha, Ekaterina I. A1 - Zharov, Vladimir P. T1 - Real-time label-free embolus detection using in vivo photoacoustic flow cytometry T2 - PLoS One N2 - Thromboembolic events are one of the world’s leading causes of death among patients. Embolus or clot formations have several etiologies including paraneoplastic, post-surgery, cauterization, transplantation, or extracorporeal circuits. Despite its medical significance, little progress has been made in early embolus detection, screening and control. The aim of our study is to test the utility of the in vivo photoacoustic (PA) flow cytometry (PAFC) technique for non-invasive embolus detection in real-time. Using in vivo PAFC, emboli were non-invasively monitored in the bloodstream of two different mouse models. The tumor-free mouse model consisted of two groups, one in which the limbs were clamped to produce vessel stasis (7 procedures), and one where the mice underwent surgery (7 procedures). The melanoma-bearing mouse model also consisted of two groups, one in which the implanted tumor underwent compression (8 procedures), and one where a surgical excision of the implanted tumor was performed (8 procedures). We demonstrated that the PAFC can detect a single embolus, and has the ability to distinguish between erythrocyte–rich (red) and leukocyte/platelet-rich (white) emboli in small vessels. We show that, in tumor-bearing mice, the level of circulating emboli was increased compared to tumor-free mice (p = 0.0013). The number of circulating emboli temporarily increased in the tumor-free control mice during vessel stasis (p = 0.033) and after surgical excisions (signed-rank p = 0.031). Similar observations were noted during tumor compression (p = 0.013) and after tumor excisions (p = 0.012). For the first time, it was possible to detect unlabeled emboli in vivo non-invasively, and to confirm the presence of pigmented tumor cells within circulating emboli. The insight on embolus dynamics during cancer progression and medical procedures highlight the clinical potential of PAFC for early detection of cancer and surgery-induced emboli to prevent the fatal thromboembolic complications by well-timed therapy. Y1 - 2016 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/41305 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-413057 SN - 1932-6203 N1 - Copyright: © 2016 Juratli et al. This is an open access article distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/ , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. VL - 11 IS - (5): e0156269 SP - 1 EP - 14 PB - PLoS CY - Lawrence, Kan. ER -