BEGIN:VCALENDAR VERSION:2.0 PRODID:Icfo X-PUBLISHED-TTL:P1W BEGIN:VEVENT UID:69db6a051aa48 DTSTART:20220429T080000Z SEQUENCE:0 TRANSP:OPAQUE LOCATION:ICFO Auditorium and Online (Teams) SUMMARY:ICFO | SUSANNA TAGLIABUE CLASS:PUBLIC DESCRIPTION:In the intensive care\, the multimodal monitoring of the patien t is crucial. The systemic physiology is routinely and comprehensively mon itored but the practical monitoring of the brain is lacking.\nHybrid diffu se optics (DO) has a potential to fill this gap by combining diffuse corre lation spectroscopy (DCS) and near-infrared spectroscopy (NIRS). DO measur es local\, microvascular cerebral perfusion/blood flow\, oxygen extraction fraction and cerebral metabolic rate of oxygen.\nTherefore\, the overarch ing purpose of this work was to boost the use of hybrid DO by validating i ts utility in clinical applications on the human brain\, especially in cri tically ill populations.\nTo achieve this goal\, new hybrid DO devices wer e constructed to enhance the data-rate and the quantification of the intra cerebral signals while synchronously acquiring data from clinical monitors . In particular\, a new platform combining time-resolved NIRS (TRS) and fa st (~40 Hz) DCS was constructed.\nThese were used in the fruitful collabor ations with the Vall d'Hebron hospital on different patient cohorts. In a population of patients undergoing surgeries the relationship with electrop hysiological assessment of cerebral metabolism\, the proprietary bispectra l index\, and the optically-derived parameters were investigated during pr opofol-induced anesthesia. This has shown that DO estimates of the oxygen metabolism correlate with this index. The additional DO information could be investigated to evaluate if it can help prevent brain damage due to ane sthesia.\nA cohort of children diagnosed with benign external hydrocephalu s undergoing invasive intracranial pressure (ICP) monitoring were monitore d during night sleep. This allowed the quantification of the cerebral hemo dynamics and metabolism during ICP waves that are indicative of future mor bidity in them. This has revealed that ICP waves are associated with hemod ynamic and metabolic oscillations. Furthermore\, these results have shown that the presence of ICP waves\, in particular B-waves\, can be observed b y DO monitoring which could\, in the future\, allow their noninvasive asse ssment in wider populations.\nAn important shortcoming for the routine cli nical use of DO has been that the results from commercial NIRS devices on clinical population are not reproducible\, often give physiologically inva lid results and differ between systems. Apart from the limitations due to the use of continuous-wave light\, one major culprit is brain heterogeneit y and underlying morphological and functional abnormalities. A comprehensi ve analysis was carried out using data from different cohorts of brain-inj ured patients to provide a set of examples and suggestions to \; estab lish quality control routines. \;\nHyperventilation is a relatively co mmon therapy\, where a decrease in blood carbon-dioxide is induced to caus e vasoconstriction in order to lower ICP. Since high ICP often leads to hy poperfusion and hypoxia\, this treatment is meant to be beneficial but the findings from clinical practice and large trials provide mixed results. I t is hypothesized that this is due to some patients suffering from misery perfusion (MP). Hybrid DO can evaluate whether the therapy causes MP. This was tested in a cohort of patients using advanced statistical methods. Th e findings indicate that MP \; is common in these patients and DO can characterize its frequency and magnitude. This paves the way for future cl inical-trials to validate the findings and evaluate the efficacy.\nOther p rotocols were also carried out as small pilot studies such as during blood transfusion. The results are reported and their potential significance is elucidated.\nOverall\, the versatility of the hybrid DO was demonstrated and new biomarkers were proposed to develop indices that are relevant to t he clinicians. \; These proof-of-principle studies will serve as a bac kbone for clinical trials and\, hopefully in the close future\, to the exp loitation of this technology in all intensive care units.\n \;\nThesis Director: Prof Dr. Turgut Durduran\nThesis Co-Director: Dr. Michal Kacprz ak DTSTAMP:20260412T094645Z END:VEVENT END:VCALENDAR