{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:37:05Z","timestamp":1760233025865,"version":"build-2065373602"},"reference-count":29,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,15]],"date-time":"2022-12-15T00:00:00Z","timestamp":1671062400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Erlangen Graduate School in Advanced Optical Technologies"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Numerous diseases such as hemorrhage, sepsis or cardiogenic shock induce a heterogeneous perfusion of the capillaries. To detect such alterations in the human blood flow pattern, diagnostic devices must provide an appropriately high spatial resolution. Shifted position-diffuse reflectance imaging (SP-DRI) has the potential to do so; it is an all-optical diagnostic technique. So far, SP-DRI has mainly been developed using Monte Carlo simulations. The present study is therefore validating this algorithm experimentally on realistic optical phantoms with thread structures down to 10 \u03bcm in diameter; a SP-DRI sensor prototype was developed and realized by means of additive manufacturing. SP-DRI turned out to be functional within this experimental framework. The position of the structures within the optical phantoms become clearly visible using SP-DRI, and the structure thickness is reflected as modulation in the SP-DRI signal amplitude; this performed well for a shift along the x axis as well as along the y axis. Moreover, SP-DRI successfully masked the pronounced influence of the illumination cone on the data. The algorithm showed significantly superior to a mere raw data inspection. Within the scope of the study, the constructive design of the SP-DRI sensor prototype is discussed and potential for improvement is explored.<\/jats:p>","DOI":"10.3390\/s22249880","type":"journal-article","created":{"date-parts":[[2022,12,16]],"date-time":"2022-12-16T03:55:39Z","timestamp":1671162939000},"page":"9880","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Experimental Validation of Shifted Position-Diffuse Reflectance Imaging (SP-DRI) on Optical Phantoms"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9852-1212","authenticated-orcid":false,"given":"Moritz","family":"Sp\u00e4th","sequence":"first","affiliation":[{"name":"Institute of Photonic Technologies, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, 91052 Erlangen, Germany"},{"name":"Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen, Germany"}]},{"given":"Alexander","family":"Romboy","sequence":"additional","affiliation":[{"name":"Institute of Photonic Technologies, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, 91052 Erlangen, Germany"}]},{"given":"Ijeoma","family":"Nzenwata","sequence":"additional","affiliation":[{"name":"Institute of Photonic Technologies, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, 91052 Erlangen, Germany"}]},{"given":"Maximilian","family":"Rohde","sequence":"additional","affiliation":[{"name":"Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen, Germany"},{"name":"Department of Oral and Maxillofacial Surgery, University Hospital Erlangen, 91054 Erlangen, Germany"}]},{"given":"Dongqin","family":"Ni","sequence":"additional","affiliation":[{"name":"Institute of Photonic Technologies, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, 91052 Erlangen, Germany"},{"name":"Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3846-3273","authenticated-orcid":false,"given":"Lisa","family":"Ackermann","sequence":"additional","affiliation":[{"name":"Institute of Photonic Technologies, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, 91052 Erlangen, Germany"},{"name":"Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen, Germany"}]},{"given":"Florian","family":"Stelzle","sequence":"additional","affiliation":[{"name":"Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen, Germany"},{"name":"Department of Oral and Maxillofacial Surgery, University Hospital Erlangen, 91054 Erlangen, Germany"}]},{"given":"Martin","family":"Hohmann","sequence":"additional","affiliation":[{"name":"Institute of Photonic Technologies, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, 91052 Erlangen, Germany"},{"name":"Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7864-7419","authenticated-orcid":false,"given":"Florian","family":"Kl\u00e4mpfl","sequence":"additional","affiliation":[{"name":"Institute of Photonic Technologies, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, 91052 Erlangen, Germany"},{"name":"Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"576","DOI":"10.1007\/s00101-002-0341-6","article-title":"\u201cOrthogonal polarization spectral imaging\u201d: Eine neue klinische Methode f\u00fcr das Monitoring der Mikrozirkulation","volume":"51","author":"Schaudig","year":"2002","journal-title":"Der Anaesthesist"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1813","DOI":"10.1007\/s00134-010-2005-3","article-title":"Monitoring the microcirculation in the critically ill patient: Current methods and future approaches","volume":"36","author":"Salgado","year":"2010","journal-title":"Intensive Care Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"244","DOI":"10.1159\/000179025","article-title":"Functional capillary density: An indicator of tissue perfusion?","volume":"15","author":"Nolte","year":"1995","journal-title":"Int. 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