Medical opticshttp://hdl.handle.net/2117/237782024-03-28T23:19:09Z2024-03-28T23:19:09ZCerebral and systemic physiological effects of wearing face masks in young adultsFischer, Jonas B.Frisk, Lisa KobayashiScholkmann, FelixDelgado-Mederos, RaquelMayos, MercedesDurduran, Turguthttp://hdl.handle.net/2117/3566712022-05-19T11:19:31Z2021-11-18T12:16:39ZCerebral and systemic physiological effects of wearing face masks in young adults
Fischer, Jonas B.; Frisk, Lisa Kobayashi; Scholkmann, Felix; Delgado-Mederos, Raquel; Mayos, Mercedes; Durduran, Turgut
The COVID-19 pandemic led to widespread mandates requiring the wearing of face masks, which led to debates on their benefits and possible adverse effects. To that end, the physiological effects at the systemic and at the brain level are of interest. We have investigated the effect of commonly available face masks (FFP2 and surgical) on cerebral hemodynamics and oxygenation, particularly microvascular cerebral blood flow (CBF) and blood/tissue oxygen saturation (StO2), measured by transcranial hybrid near-infrared spectroscopies and on systemic physiology in 13 healthy adults (ages: 23 to 33 y). The results indicate small but significant changes in cerebral hemodynamics while wearing a mask. However, these changes are comparable to those of daily life activities. This platform and the protocol provides the basis for large or targeted studies of the effects of mask wearing in different populations and while performing critical tasks
2021-11-18T12:16:39ZFischer, Jonas B.Frisk, Lisa KobayashiScholkmann, FelixDelgado-Mederos, RaquelMayos, MercedesDurduran, TurgutThe COVID-19 pandemic led to widespread mandates requiring the wearing of face masks, which led to debates on their benefits and possible adverse effects. To that end, the physiological effects at the systemic and at the brain level are of interest. We have investigated the effect of commonly available face masks (FFP2 and surgical) on cerebral hemodynamics and oxygenation, particularly microvascular cerebral blood flow (CBF) and blood/tissue oxygen saturation (StO2), measured by transcranial hybrid near-infrared spectroscopies and on systemic physiology in 13 healthy adults (ages: 23 to 33 y). The results indicate small but significant changes in cerebral hemodynamics while wearing a mask. However, these changes are comparable to those of daily life activities. This platform and the protocol provides the basis for large or targeted studies of the effects of mask wearing in different populations and while performing critical tasksBlood flow response to orthostatic challenge identifies signatures of the failure of static cerebral autoregulation in patients with cerebrovascular diseaseGregori-Pla, ClaraMesquita, Rickson C.Favilla, Christopher G.Busch, David R.Blanco, IgorZirak, PeymanLisa Kobayashi, FriskAvtzi, StellaMaruccia, FedericaGiacalone, GiacomoCotta, GianlucaCamps-Renom, PolMullen, Michael T.Martí-Fàbregas, JoanPrats-Sánchez, LuísMartínez-Domeño, AlejandroKasner, Scott E.Greenberg, Joel H.Zhou, ChaoEdlow, Brian L.Putt, Mary E.Detre, John A.Yodh, Arjun G.Durduran, TurgutDelgado-Mederos, Raquelhttp://hdl.handle.net/2117/3475082022-05-22T10:45:48Z2021-06-18T08:35:17ZBlood flow response to orthostatic challenge identifies signatures of the failure of static cerebral autoregulation in patients with cerebrovascular disease
Gregori-Pla, Clara; Mesquita, Rickson C.; Favilla, Christopher G.; Busch, David R.; Blanco, Igor; Zirak, Peyman; Lisa Kobayashi, Frisk; Avtzi, Stella; Maruccia, Federica; Giacalone, Giacomo; Cotta, Gianluca; Camps-Renom, Pol; Mullen, Michael T.; Martí-Fàbregas, Joan; Prats-Sánchez, Luís; Martínez-Domeño, Alejandro; Kasner, Scott E.; Greenberg, Joel H.; Zhou, Chao; Edlow, Brian L.; Putt, Mary E.; Detre, John A.; Yodh, Arjun G.; Durduran, Turgut; Delgado-Mederos, Raquel
Background
The cortical microvascular cerebral blood flow response (CBF) to different changes in head-of-bed (HOB) position has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS) technique. However, the relationship between these relative ΔCBF changes and associated systemic blood pressure changes has not been studied, even though blood pressure is a major driver of cerebral blood flow.
Methods
Transcranial DCS data from four studies measuring bilateral frontal microvascular cerebral blood flow in healthy controls (n = 15), patients with asymptomatic severe internal carotid artery stenosis (ICA, n = 27), and patients with acute ischemic stroke (AIS, n = 72) were aggregated. DCS-measured CBF was measured in response to a short head-of-bed (HOB) position manipulation protocol (supine/elevated/supine, 5 min at each position). In a sub-group (AIS, n = 26; ICA, n = 14; control, n = 15), mean arterial pressure (MAP) was measured dynamically during the protocol.
Results
After elevated positioning, DCS CBF returned to baseline supine values in controls (p = 0.890) but not in patients with AIS (9.6% [6.0,13.3], mean 95% CI, p < 0.001) or ICA stenosis (8.6% [3.1,14.0], p = 0.003)). MAP in AIS patients did not return to baseline values (2.6 mmHg [0.5, 4.7], p = 0.018), but in ICA stenosis patients and controls did. Instead ipsilesional but not contralesional CBF was correlated with MAP (AIS 6.0%/mmHg [− 2.4,14.3], p = 0.038; ICA stenosis 11.0%/mmHg [2.4,19.5], p < 0.001).
Conclusions
The observed associations between ipsilateral CBF and MAP suggest that short HOB position changes may elicit deficits in cerebral autoregulation in cerebrovascular disorders. Additional research is required to further characterize this phenomenon.
2021-06-18T08:35:17ZGregori-Pla, ClaraMesquita, Rickson C.Favilla, Christopher G.Busch, David R.Blanco, IgorZirak, PeymanLisa Kobayashi, FriskAvtzi, StellaMaruccia, FedericaGiacalone, GiacomoCotta, GianlucaCamps-Renom, PolMullen, Michael T.Martí-Fàbregas, JoanPrats-Sánchez, LuísMartínez-Domeño, AlejandroKasner, Scott E.Greenberg, Joel H.Zhou, ChaoEdlow, Brian L.Putt, Mary E.Detre, John A.Yodh, Arjun G.Durduran, TurgutDelgado-Mederos, RaquelBackground
The cortical microvascular cerebral blood flow response (CBF) to different changes in head-of-bed (HOB) position has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS) technique. However, the relationship between these relative ΔCBF changes and associated systemic blood pressure changes has not been studied, even though blood pressure is a major driver of cerebral blood flow.
Methods
Transcranial DCS data from four studies measuring bilateral frontal microvascular cerebral blood flow in healthy controls (n = 15), patients with asymptomatic severe internal carotid artery stenosis (ICA, n = 27), and patients with acute ischemic stroke (AIS, n = 72) were aggregated. DCS-measured CBF was measured in response to a short head-of-bed (HOB) position manipulation protocol (supine/elevated/supine, 5 min at each position). In a sub-group (AIS, n = 26; ICA, n = 14; control, n = 15), mean arterial pressure (MAP) was measured dynamically during the protocol.
Results
After elevated positioning, DCS CBF returned to baseline supine values in controls (p = 0.890) but not in patients with AIS (9.6% [6.0,13.3], mean 95% CI, p < 0.001) or ICA stenosis (8.6% [3.1,14.0], p = 0.003)). MAP in AIS patients did not return to baseline values (2.6 mmHg [0.5, 4.7], p = 0.018), but in ICA stenosis patients and controls did. Instead ipsilesional but not contralesional CBF was correlated with MAP (AIS 6.0%/mmHg [− 2.4,14.3], p = 0.038; ICA stenosis 11.0%/mmHg [2.4,19.5], p < 0.001).
Conclusions
The observed associations between ipsilateral CBF and MAP suggest that short HOB position changes may elicit deficits in cerebral autoregulation in cerebrovascular disorders. Additional research is required to further characterize this phenomenon.Neurodevelopmental profile in children with benign external hydrocephalus syndrome. A pilot cohort studyMaruccia, FedericaGomáriz, LauraRosas, KatiuskaDurduran, TurgutParedes-Carmona, FernandoSahuquillo, JuanPoca, Maria A.http://hdl.handle.net/2117/3464462022-05-22T04:29:20Z2021-06-01T08:58:47ZNeurodevelopmental profile in children with benign external hydrocephalus syndrome. A pilot cohort study
Maruccia, Federica; Gomáriz, Laura; Rosas, Katiuska; Durduran, Turgut; Paredes-Carmona, Fernando; Sahuquillo, Juan; Poca, Maria A.
The management of children with benign external hydrocephalus (BEH) remains controversial. Most BEH children do well in the long-term, but a substantial number have temporary or permanent psychomotor delays. The study aims to assess the prevalence and pattern of neurodevelopmental delay in a cohort of children with BEH.
2021-06-01T08:58:47ZMaruccia, FedericaGomáriz, LauraRosas, KatiuskaDurduran, TurgutParedes-Carmona, FernandoSahuquillo, JuanPoca, Maria A.The management of children with benign external hydrocephalus (BEH) remains controversial. Most BEH children do well in the long-term, but a substantial number have temporary or permanent psychomotor delays. The study aims to assess the prevalence and pattern of neurodevelopmental delay in a cohort of children with BEH.Cerebral oxygenation and blood flow in normal term infants at rest measured by a hybrid near-infrared device (BabyLux)Andresen, BjørnCarli, Agnese DeFumagalli, MonicaGiovannella, MartinaDurduran, TurgutWeigel, Udo MichaelContini, DavideSpinelli, LorenzoTorricelli, AlessandroGreise, Gormhttp://hdl.handle.net/2117/1655422020-07-23T23:31:30Z2019-07-03T13:15:16ZCerebral oxygenation and blood flow in normal term infants at rest measured by a hybrid near-infrared device (BabyLux)
Andresen, Bjørn; Carli, Agnese De; Fumagalli, Monica; Giovannella, Martina; Durduran, Turgut; Weigel, Udo Michael; Contini, Davide; Spinelli, Lorenzo; Torricelli, Alessandro; Greise, Gorm
2019-07-03T13:15:16ZAndresen, BjørnCarli, Agnese DeFumagalli, MonicaGiovannella, MartinaDurduran, TurgutWeigel, Udo MichaelContini, DavideSpinelli, LorenzoTorricelli, AlessandroGreise, GormLiquid phantoms for near-infrared and diffuse correlation spectroscopies with tunable optical and dynamic propertiesCortese, LorenzoPresti, Giuseppe LoPagliazzi, MarcoContini, DavideMora, Alberto DallaPifferi, AntonioVenkata Sekar, Sanathana KonugoluSpinelli, LorenzoTaroni, PaolaZanoletti, MartaWeigel, Udo M.Fraguier, Sixte deNguyen-Dihn, AnRosinski, BogdanDurduran, Durduranhttp://hdl.handle.net/2117/1160202022-05-17T11:53:36Z2018-04-06T11:51:02ZLiquid phantoms for near-infrared and diffuse correlation spectroscopies with tunable optical and dynamic properties
Cortese, Lorenzo; Presti, Giuseppe Lo; Pagliazzi, Marco; Contini, Davide; Mora, Alberto Dalla; Pifferi, Antonio; Venkata Sekar, Sanathana Konugolu; Spinelli, Lorenzo; Taroni, Paola; Zanoletti, Marta; Weigel, Udo M.; Fraguier, Sixte de; Nguyen-Dihn, An; Rosinski, Bogdan; Durduran, Durduran
We present the recipe and characterization for preparing liquid phantoms that are suitable for both near-infrared spectroscopy and diffuse correlation spectroscopy. The phantoms have well-defined and tunable optical and dynamic properties, and consist of a solution of water and glycerol with fat emulsion as the scattering element. The recipe takes into account the effect of bulk refractive index changes due to the addition of glycerol, which is commonly used to alter the sample viscosity.
2018-04-06T11:51:02ZCortese, LorenzoPresti, Giuseppe LoPagliazzi, MarcoContini, DavideMora, Alberto DallaPifferi, AntonioVenkata Sekar, Sanathana KonugoluSpinelli, LorenzoTaroni, PaolaZanoletti, MartaWeigel, Udo M.Fraguier, Sixte deNguyen-Dihn, AnRosinski, BogdanDurduran, DurduranWe present the recipe and characterization for preparing liquid phantoms that are suitable for both near-infrared spectroscopy and diffuse correlation spectroscopy. The phantoms have well-defined and tunable optical and dynamic properties, and consist of a solution of water and glycerol with fat emulsion as the scattering element. The recipe takes into account the effect of bulk refractive index changes due to the addition of glycerol, which is commonly used to alter the sample viscosity.Cerebral vasoreactivity in response to a headof-bed position change is altered in patients with moderate and severe obstructive sleep apneaGregori-Pla, ClaraCotta, GianlucaBlanco, IgorZirak, PeymanGiovannella, MartinaMola, AnnaFortuna, AnaDurduran, TurgutMayos, Mercedeshttp://hdl.handle.net/2117/1152842022-05-17T13:01:36Z2018-03-16T12:19:20ZCerebral vasoreactivity in response to a headof-bed position change is altered in patients with moderate and severe obstructive sleep apnea
Gregori-Pla, Clara; Cotta, Gianluca; Blanco, Igor; Zirak, Peyman; Giovannella, Martina; Mola, Anna; Fortuna, Ana; Durduran, Turgut; Mayos, Mercedes
Obstructive sleep apnea (OSA) can impair cerebral vasoreactivity and is associated with an
increased risk of cerebrovascular disease. Unfortunately, an easy-to-use, non-invasive, portable
monitor of cerebral vasoreactivity does not exist. Therefore, we have evaluated the
use of near-infrared diffuse correlation spectroscopy to measure the microvascular cerebral
blood flow (CBF) response to a mild head-of-bed position change as a biomarker for the
evaluation of cerebral vasoreactivity alteration due to chronic OSA. Furthermore, we have
monitored the effect of two years of continuous positive airway pressure (CPAP) treatment
on the cerebral vasoreactivity.
2018-03-16T12:19:20ZGregori-Pla, ClaraCotta, GianlucaBlanco, IgorZirak, PeymanGiovannella, MartinaMola, AnnaFortuna, AnaDurduran, TurgutMayos, MercedesObstructive sleep apnea (OSA) can impair cerebral vasoreactivity and is associated with an
increased risk of cerebrovascular disease. Unfortunately, an easy-to-use, non-invasive, portable
monitor of cerebral vasoreactivity does not exist. Therefore, we have evaluated the
use of near-infrared diffuse correlation spectroscopy to measure the microvascular cerebral
blood flow (CBF) response to a mild head-of-bed position change as a biomarker for the
evaluation of cerebral vasoreactivity alteration due to chronic OSA. Furthermore, we have
monitored the effect of two years of continuous positive airway pressure (CPAP) treatment
on the cerebral vasoreactivity.Transcranial diffuse optical assessment of the microvascular reperfusion after thrombolysis for acute ischemic strokeDelgado-Mederos, RaquelGregori Pla, ClaraZirak, PeymanBlanco, IgorDinia, LaviniaMarín, RebecaDurduran, TurgutMartí-Fàbregas, Joanhttp://hdl.handle.net/2117/1143612022-07-13T07:34:26Z2018-02-22T09:20:06ZTranscranial diffuse optical assessment of the microvascular reperfusion after thrombolysis for acute ischemic stroke
Delgado-Mederos, Raquel; Gregori Pla, Clara; Zirak, Peyman; Blanco, Igor; Dinia, Lavinia; Marín, Rebeca; Durduran, Turgut; Martí-Fàbregas, Joan
In this pilot study, we have evaluated bedside diffuse optical monitoring combining diffuse correlation spectroscopy and near-infrared diffuse optical spectroscopy to assess the effect of thrombolysis with an intravenous recombinant tissue plasminogen activator (rtPA) on cerebral hemodynamics in an acute ischemic stroke. Frontal lobes of five patients with an acute middle cerebral artery occlusion were measured bilaterally during rtPA treatment. Both ipsilesional and contralesional hemispheres showed significant increases in cerebral blood flow, total hemoglobin concentration and oxy-hemoglobin concentration during the first 2.5 hours after rtPA bolus. The increases were faster and higher in the ipsilesional hemisphere. The results show that bedside optical monitoring can detect the effect of reperfusion therapy for ischemic stroke in real-time.
2018-02-22T09:20:06ZDelgado-Mederos, RaquelGregori Pla, ClaraZirak, PeymanBlanco, IgorDinia, LaviniaMarín, RebecaDurduran, TurgutMartí-Fàbregas, JoanIn this pilot study, we have evaluated bedside diffuse optical monitoring combining diffuse correlation spectroscopy and near-infrared diffuse optical spectroscopy to assess the effect of thrombolysis with an intravenous recombinant tissue plasminogen activator (rtPA) on cerebral hemodynamics in an acute ischemic stroke. Frontal lobes of five patients with an acute middle cerebral artery occlusion were measured bilaterally during rtPA treatment. Both ipsilesional and contralesional hemispheres showed significant increases in cerebral blood flow, total hemoglobin concentration and oxy-hemoglobin concentration during the first 2.5 hours after rtPA bolus. The increases were faster and higher in the ipsilesional hemisphere. The results show that bedside optical monitoring can detect the effect of reperfusion therapy for ischemic stroke in real-time.Concurrent measurement of cerebral hemodynamics and electroencephalography during transcranial direct current stimulationGiovannella, MartinaIbañez, DavidGregori-Pla, ClaraKacprzak, MichalMitjà, GuillemRuffini, GiulioDurduran, Turguthttp://hdl.handle.net/2117/1135822022-05-17T17:12:25Z2018-02-01T16:35:43ZConcurrent measurement of cerebral hemodynamics and electroencephalography during transcranial direct current stimulation
Giovannella, Martina; Ibañez, David; Gregori-Pla, Clara; Kacprzak, Michal; Mitjà, Guillem; Ruffini, Giulio; Durduran, Turgut
Transcranial direct current stimulation (tDCS) is currently being used for research and treatment of some neurological and neuropsychiatric disorders, as well as for improvement of cognitive functions. In order to better understand cerebral response to the stimulation and to redefine protocols and dosage, its effects must be monitored. To this end, we have used functional diffuse correlation spectroscopy (fDCS) and time-resolved functional near-infrared spectroscopy (TR-fNIRS) together with electroencephalography (EEG) during and after stimulation of the frontal cortex. Twenty subjects participated in two sessions of stimulation with two different polarity montages and twelve also underwent a sham session. Cerebral blood flow and oxyhemoglobin concentration increased during and after active stimulation in the region under the stimulation electrode while deoxyhemoglobin concentration decreased. The EEG spectrum displayed statistically significant power changes across different stimulation sessions in delta (2 to 4 Hz), theta (4 to 8 Hz), and beta (12 to 18 Hz) bands. Results suggest that fDCS and TR-fNIRS can be employed as neuromonitors of the effects of transcranial electrical stimulation and can be used together with EEG.
2018-02-01T16:35:43ZGiovannella, MartinaIbañez, DavidGregori-Pla, ClaraKacprzak, MichalMitjà, GuillemRuffini, GiulioDurduran, TurgutTranscranial direct current stimulation (tDCS) is currently being used for research and treatment of some neurological and neuropsychiatric disorders, as well as for improvement of cognitive functions. In order to better understand cerebral response to the stimulation and to redefine protocols and dosage, its effects must be monitored. To this end, we have used functional diffuse correlation spectroscopy (fDCS) and time-resolved functional near-infrared spectroscopy (TR-fNIRS) together with electroencephalography (EEG) during and after stimulation of the frontal cortex. Twenty subjects participated in two sessions of stimulation with two different polarity montages and twelve also underwent a sham session. Cerebral blood flow and oxyhemoglobin concentration increased during and after active stimulation in the region under the stimulation electrode while deoxyhemoglobin concentration decreased. The EEG spectrum displayed statistically significant power changes across different stimulation sessions in delta (2 to 4 Hz), theta (4 to 8 Hz), and beta (12 to 18 Hz) bands. Results suggest that fDCS and TR-fNIRS can be employed as neuromonitors of the effects of transcranial electrical stimulation and can be used together with EEG.Time-resolved near infrared light propagation using frequency domain superpositionWojtkiewicz, StanislawDurduran, TurgutDehghani, Hamidhttp://hdl.handle.net/2117/1129382021-05-16T16:55:52Z2018-01-18T10:57:34ZTime-resolved near infrared light propagation using frequency domain superposition
Wojtkiewicz, Stanislaw; Durduran, Turgut; Dehghani, Hamid
Time-resolved temporal point spread function (TPSF) measurement of near infrared spectroscopic (NIRS) data allows the estimation of absorption and reduced scattering properties of biological tissues. Such analysis requires an iterative calculation of the theoretical TPSF curve using mathematical and computational models of the domain being imaged which are computationally complex and expensive. In this work, an efficient methodology for representing the TPSF data using a superposition of cosines calculated in frequency domain is presented. The proposed method is outlined and tested on finite element realistic models of the human neck and head. Using an adult head model containing ~140k nodes, the TPSF calculation at each node for one source is accelerated from 3.11 s to 1.29 s within an error limit of ± 5% related to the time domain calculation method.
2018-01-18T10:57:34ZWojtkiewicz, StanislawDurduran, TurgutDehghani, HamidTime-resolved temporal point spread function (TPSF) measurement of near infrared spectroscopic (NIRS) data allows the estimation of absorption and reduced scattering properties of biological tissues. Such analysis requires an iterative calculation of the theoretical TPSF curve using mathematical and computational models of the domain being imaged which are computationally complex and expensive. In this work, an efficient methodology for representing the TPSF data using a superposition of cosines calculated in frequency domain is presented. The proposed method is outlined and tested on finite element realistic models of the human neck and head. Using an adult head model containing ~140k nodes, the TPSF calculation at each node for one source is accelerated from 3.11 s to 1.29 s within an error limit of ± 5% related to the time domain calculation method.Compact, multi-exposure speckle contrast optical spectroscopy (SCOS) device for measuring deep tissue blood flowDragojević, TanjaHollmann, Joseph L.Tamborini, DavidePortaluppi, DavideButtafava, MauroCulver, Joseph P.Villa, FedericaDurduran, Turguthttp://hdl.handle.net/2117/1129372021-05-16T16:50:25Z2018-01-18T10:09:33ZCompact, multi-exposure speckle contrast optical spectroscopy (SCOS) device for measuring deep tissue blood flow
Dragojević, Tanja; Hollmann, Joseph L.; Tamborini, Davide; Portaluppi, Davide; Buttafava, Mauro; Culver, Joseph P.; Villa, Federica; Durduran, Turgut
Speckle contrast optical spectroscopy (SCOS) measures absolute blood flow in deep tissue, by taking advantage of multi-distance (previously reported in the literature) or multi-exposure (reported here) approach. This method promises to use inexpensive detectors to obtain good signal-to-noise ratio, but it has not yet been implemented in a suitable manner for a mass production. Here we present a new, compact, low power consumption, 32 by 2 single photon avalanche diode (SPAD) array that has no readout noise, low dead time and has high sensitivity in low light conditions, such as in vivo measurements. To demonstrate the capability to measure blood flow in deep tissue, healthy volunteers were measured, showing no significant differences from the diffuse correlation spectroscopy. In the future, this array can be miniaturized to a low-cost, robust, battery operated wireless device paving the way for measuring blood flow in a wide-range of applications from sport injury recovery and training to, on-field concussion detection to wearables.
2018-01-18T10:09:33ZDragojević, TanjaHollmann, Joseph L.Tamborini, DavidePortaluppi, DavideButtafava, MauroCulver, Joseph P.Villa, FedericaDurduran, TurgutSpeckle contrast optical spectroscopy (SCOS) measures absolute blood flow in deep tissue, by taking advantage of multi-distance (previously reported in the literature) or multi-exposure (reported here) approach. This method promises to use inexpensive detectors to obtain good signal-to-noise ratio, but it has not yet been implemented in a suitable manner for a mass production. Here we present a new, compact, low power consumption, 32 by 2 single photon avalanche diode (SPAD) array that has no readout noise, low dead time and has high sensitivity in low light conditions, such as in vivo measurements. To demonstrate the capability to measure blood flow in deep tissue, healthy volunteers were measured, showing no significant differences from the diffuse correlation spectroscopy. In the future, this array can be miniaturized to a low-cost, robust, battery operated wireless device paving the way for measuring blood flow in a wide-range of applications from sport injury recovery and training to, on-field concussion detection to wearables.