Diss. (sammanfattning) Linköping : Linköpings universitet, 2008. / Härtill 4 uppsatser.

No description available.

A quimioterapia e a radioterapia são modalidades terapêuticas não cirúrgicas aplicadas a pacientes com neoplasias malignas. A mucosite oral (MO) é uma inflamação da mucosa oral decorrente destas terapias antineoplásicas, manifestando-se por atrofia, inchaço, eritema e úlcera, comprometendo a qualidade de vida. A patogênese da mucosite oral envolve uma cascata de eventos de natureza inflamatória que culminam em alterações no epitélio e no tecido conjuntivo. Dentre estas modificações destacam-se as alterações na microvascularização, as quais precedem as alterações epiteliais na mucosa oral induzida por radiação e pelos agentes quimioterápicos. A Fluxometria Laser Doppler é um método não invasivo que permite avaliar parâmetros clínicos da microcirculação através do monitoramento do fluxo continuamente, em tempo real. O objetivo deste estudo foi avaliar a fluxo sanguíneo na região geniana em pacientes sob radioterapia de cabeça e pescoço ou quimioterapia através da técnica de Fluxometria Laser Doppler e comparar a graduação de mucosite oral e dor com dados obtidos na avaliação do fluxo sanguíneo. Este estudo observacional e prospectivo teve uma amostra de 14 pacientes oncológicos que foram avaliados antes do início da terapia antineoplásica e durante a fase intensiva da radioterapia de cabeça e pescoço ou quimioterapia, em 7 momentos. Para esta avaliação foi utilizado o Fluxômetro Laser Doppler para o registro do fluxo sanguíneo; as escalas da OMS (Organização Mundial da Saúde) e OMAS (Oral Mucositis Assessment Scale) para a avaliação do grau de mucosite; e Escala Visual Analógica (EVA) para a avaliação da dor em mucosa oral. Ao se comparar o fluxo sanguíneo nos tempos T1, T2, T3, T4, T5 e T6 com o T0, para os pacientes submetidos a radioterapia de cabeça e pescoço, não houve diferença estatística (p>0,05). Para os pacientes sob quimioterapia, houve diferença estatística nos tempo T1 (p=0,033) e T6 (p=0,043). Houve correlação positiva fraca entre as escalas para avaliação de mucosite oral (OMS (p=0,031) e OMAS (p=0,009)) e o fluxo sanguíneo. Não houve grau de relação entre dor induzida por mucosite oral e fluxo sanguíneo (p>0,05). A Fluxometria Laser Doppler permitiu a observação da dinâmica microvascular da região geniana da face em pacientes sob terapia antineoplásica e com risco de desenvolvimento de mucosite oral. Nos pacientes sob quimioterapia, houve aumento de perfusão cutânea na face nos tempos iniciais da MO, com progressiva redução do fluxo no decorrer do ciclo de quimioterapia. / Chemotherapy and radiotherapy are non surgical therapeutic modalities to malignancies. Oral mucositis is a inflammation of the oral mucosa due to these cancer therapy, typically manifesting as atrophy, swelling, erythema and ulceration compromising the quality of life. The pathogenesis of oral mucositis (OM) involves a cascade of inflammation events that result in changes in the epithelial layer and connective tissue, including microvascular modifications. These modifications precede epithelial changes induced by radiation therapy and chemotherapeutic agents, thereby modifications in blood flow may be a predictive factor of the severity of oral mucositis. Laser Doppler flowmetry (LDF) is a non invasive method enabling the monitoring of microvascular blood flow continuously in real time. The aim of this study was to evaluate the blood flow in the genius region in patients undergoing head and neck radiation and/or chemotherapy by Laser Doppler Flowmetry and compare the degree of oral mucositis and pain with data obtained in the evaluation of blood flow. This prospective observational study had a sample of 14 oncologic patients who were evaluated before and during the intensive phase of head and neck radiotherapy or chemotherapy in 7 times. For this evaluation, we used the Laser Doppler Flowmeter to measure blood flow; WHO scale (World Health Organization) and OMAS (Oral Mucositis Assessment Scale) for assessing the severity of mucositis; and Visual Analogue Scale (VAS) for pain assessment in oral mucosa. When we compare blood flow in T1, T2, T3,T4, T5 and T6 with T0, for patients undergoing radiotherapy for head and neck, there was no statistical difference (p> 0.05). For patients undergoing chemotherapy, there was a statistical difference in time T1 (p = 0.033) and T6 (p = 0.043). There was a weak positive correlation between the scale for assessing oral mucositis (WHO (p = 0.031) and OMAS (p = 0.009)) and blood flow. There was no relation degree pain induced oral mucositis and blood flow (p>0.05). Laser Doppler flowmetry allowed the observation of microvascular dynamics in the genian region of the face in patients undergoing antineoplastic therapy and risk of developing mucositis. In patients undergoing chemotherapy, there was an increase of skin perfusion in the face in the early days of the OM, with progressive reduction in flow during the course of chemotherapy.

Licentiatavhandling (sammanfattning) Linköping : Linköpings universitet, 2009. / Härtill 2 uppsatser.

[Truncated abstract] Purpose: To improve our ability to interpret and validate Heidelberg Retina Flowmeter (HRF) flow images by recording flow measurements from specific regions of the retinal vasculature in in-vitro and in-vivo eye models in which retinal blood flow can be manipulated. Methods: The first experiments utilised an isolated perfused pig eyes perfused with a 50%/50% Krebs/RBC solution at known flow rates ranging from zero to 300 μl/min. After HRF image acquisition, the retinal vasculature was perfused with fluorescein isothiocyanate (FITC), for fluorescence microscopy. Using the standard HRF software and a 10×10 pixel measurement window, flow rates were measured from a retinal artery, vein, arteriole, venule, and the retinal capillary bed and a capillary-free-zone. The relationship between HRF measured flow and perfusion flow in the different measurement regions was determined. For the second study, HRF flow images were acquired at retinal sites in Brown Norway rats over a range of focus levels before and after cessation of retinal blood flow by laser-induced central retinal artery occlusion. Using the 10×10 pixel and 4×4 pixel measurement windows, HRF measured flow was performed in retinal artery, vein, arteriole, capillary and choroidal vessel locations. The relationship between HRF measured flow and focus depth was determined for each location before and after central retinal artery occlusion. At the conclusion of each experiment the effect of reduction of systemic blood pressure (by exsanguination) on HRF flow measurements in choroidal vessels and in locations without visible choroidal vessels was assessed. Finally, HRF flow measurements were acquired after euthanasia, to determine the HRF flow signal which was still present under zero biological flow conditions (the zerooffset). Results: In the isolated perfused pig eye experiments it was found that the HRF flow response varied according to vascular location. At zero perfusate flow, HRF flow was consistently greater than zero at all locations, averaging 171.9 ± 44.7 AU (n=97), representing background noise. Arteries and veins yielded the highest HRF measured flow values, but the relationship between HRF measured flow and perfusate flow was not linear. In arterioles the HRF flow was more linear over a broader range of perfusate flow rates but the peak flow signal was an order of magnitude smaller than that in arteries and veins. Both the linearity and magnitude of the flow signal in venules was less than that in arterioles.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2005. / Härtill 4 uppsatser.

abstract: Objective: Examine cardiovascular response to OMT via central and peripheral measurements. Methods: Central and peripheral cardiovascular signals of asymptomatic human subjects were monitored during a procedure with alternating rest and active phases. Active phases included systemic perturbations and application of controlled vertebral pressure (OMT) by an experienced osteopathic physician. Pulse plethysmograph and laser Doppler flow sensors measured peripheral flow from index and middle fingers bilaterally. A three-lead EKG monitored cardiac activity. The biosignals were recorded continuously, in real time, and analyzed in time and frequency domains. Results from the control group (n=11), without OMT, and active group (n=16), with OMT, were compared. Peripheral (n=5) and central responders (n=6), subsets of the active group showing stronger peripheral or central response, were examined. In an additional effort, a modified clinical device recorded spectral Doppler ultrasound signals of the radial and dorsalis pedis arteries of clinically asymptomatic human subjects. Controlled physiologic provocations (limb occlusion and elevation), were performed. Time domain and spectral analyses were completed. Results: In the human subject study, the time wave characteristics and spectral analysis resulted in similar trends. Peripheral blood flow attenuated in the control group over time, while it was maintained in the active group, and increased specifically during OMT in the responder groups. Heart rate remained around 65 BPM in the control group, fluctuated between 64-68 BPM in the active group, and dropped 4 and 3 BPM in the peripheral and central responder groups, respectively. The effect in the OMT group was statistically significant compared to no-OMT, however, was not statistically significant within-groups. For the preliminary spectral ultrasound Doppler study, segmental flow was successfully monitored. A prototype "Quick Assessment" tool was developed, providing instant post-processing results for clinical use. Conclusions: OMT along the vertebral column may influence autonomic processes that regulate heart rate and peripheral vascular flow. / Dissertation/Thesis / Masters Thesis Bioengineering 2014

A quimioterapia e a radioterapia são modalidades terapêuticas não cirúrgicas aplicadas a pacientes com neoplasias malignas. A mucosite oral (MO) é uma inflamação da mucosa oral decorrente destas terapias antineoplásicas, manifestando-se por atrofia, inchaço, eritema e úlcera, comprometendo a qualidade de vida. A patogênese da mucosite oral envolve uma cascata de eventos de natureza inflamatória que culminam em alterações no epitélio e no tecido conjuntivo. Dentre estas modificações destacam-se as alterações na microvascularização, as quais precedem as alterações epiteliais na mucosa oral induzida por radiação e pelos agentes quimioterápicos. A Fluxometria Laser Doppler é um método não invasivo que permite avaliar parâmetros clínicos da microcirculação através do monitoramento do fluxo continuamente, em tempo real. O objetivo deste estudo foi avaliar a fluxo sanguíneo na região geniana em pacientes sob radioterapia de cabeça e pescoço ou quimioterapia através da técnica de Fluxometria Laser Doppler e comparar a graduação de mucosite oral e dor com dados obtidos na avaliação do fluxo sanguíneo. Este estudo observacional e prospectivo teve uma amostra de 14 pacientes oncológicos que foram avaliados antes do início da terapia antineoplásica e durante a fase intensiva da radioterapia de cabeça e pescoço ou quimioterapia, em 7 momentos. Para esta avaliação foi utilizado o Fluxômetro Laser Doppler para o registro do fluxo sanguíneo; as escalas da OMS (Organização Mundial da Saúde) e OMAS (Oral Mucositis Assessment Scale) para a avaliação do grau de mucosite; e Escala Visual Analógica (EVA) para a avaliação da dor em mucosa oral. Ao se comparar o fluxo sanguíneo nos tempos T1, T2, T3, T4, T5 e T6 com o T0, para os pacientes submetidos a radioterapia de cabeça e pescoço, não houve diferença estatística (p>0,05). Para os pacientes sob quimioterapia, houve diferença estatística nos tempo T1 (p=0,033) e T6 (p=0,043). Houve correlação positiva fraca entre as escalas para avaliação de mucosite oral (OMS (p=0,031) e OMAS (p=0,009)) e o fluxo sanguíneo. Não houve grau de relação entre dor induzida por mucosite oral e fluxo sanguíneo (p>0,05). A Fluxometria Laser Doppler permitiu a observação da dinâmica microvascular da região geniana da face em pacientes sob terapia antineoplásica e com risco de desenvolvimento de mucosite oral. Nos pacientes sob quimioterapia, houve aumento de perfusão cutânea na face nos tempos iniciais da MO, com progressiva redução do fluxo no decorrer do ciclo de quimioterapia. / Chemotherapy and radiotherapy are non surgical therapeutic modalities to malignancies. Oral mucositis is a inflammation of the oral mucosa due to these cancer therapy, typically manifesting as atrophy, swelling, erythema and ulceration compromising the quality of life. The pathogenesis of oral mucositis (OM) involves a cascade of inflammation events that result in changes in the epithelial layer and connective tissue, including microvascular modifications. These modifications precede epithelial changes induced by radiation therapy and chemotherapeutic agents, thereby modifications in blood flow may be a predictive factor of the severity of oral mucositis. Laser Doppler flowmetry (LDF) is a non invasive method enabling the monitoring of microvascular blood flow continuously in real time. The aim of this study was to evaluate the blood flow in the genius region in patients undergoing head and neck radiation and/or chemotherapy by Laser Doppler Flowmetry and compare the degree of oral mucositis and pain with data obtained in the evaluation of blood flow. This prospective observational study had a sample of 14 oncologic patients who were evaluated before and during the intensive phase of head and neck radiotherapy or chemotherapy in 7 times. For this evaluation, we used the Laser Doppler Flowmeter to measure blood flow; WHO scale (World Health Organization) and OMAS (Oral Mucositis Assessment Scale) for assessing the severity of mucositis; and Visual Analogue Scale (VAS) for pain assessment in oral mucosa. When we compare blood flow in T1, T2, T3,T4, T5 and T6 with T0, for patients undergoing radiotherapy for head and neck, there was no statistical difference (p> 0.05). For patients undergoing chemotherapy, there was a statistical difference in time T1 (p = 0.033) and T6 (p = 0.043). There was a weak positive correlation between the scale for assessing oral mucositis (WHO (p = 0.031) and OMAS (p = 0.009)) and blood flow. There was no relation degree pain induced oral mucositis and blood flow (p>0.05). Laser Doppler flowmetry allowed the observation of microvascular dynamics in the genian region of the face in patients undergoing antineoplastic therapy and risk of developing mucositis. In patients undergoing chemotherapy, there was an increase of skin perfusion in the face in the early days of the OM, with progressive reduction in flow during the course of chemotherapy.

The cerebral microcirculation consists of a complex network of small blood vessels that support nerve cells with oxygen and nutrition. The blood flow and oxygen delivery in the microcirculatory blood vessels are regulated through mechanisms which may be influenced or impaired by disease or brain damage resulting from conditions such as brain tumors, traumatic brain injury or subarachnoid hemorrhage (SAH). Monitoring of parameters relating to the microvascular circulation is therefore needed in the clinical setting. Optical techniques such as diffuse reflectance spectroscopy (DRS) and laser Doppler flowmetry (LDF) are capable of estimating the oxygen saturation (SO2) and tracking the microvascular blood flow (perfusion) using a fiber optic probe. This thesis presents the work carried out to adapt DRS and LDF for monitoring cerebral microcirculation in the human brain. A method for real-time estimation of SO2 in brain tissue was developed based on the P3 approximation of diffuse light transport and quadratic polynomial fit to the measured DRS signal. A custom-made fiberoptic probe was constructed for measurements during tumor surgery and in neurointensive care. Software modules with specific user interface for LDF and DRS were programmed to process, record and present parameters such as perfusion, total backscattered light, heart rate, pulsatility index, blood fraction and SO2 from acquired signals. The systems were evaluated on skin, and experimentally by using optical phantoms with properties mimicking brain tissue. The oxygen pressure (pO2) in the phantoms was regulated to track spectroscopic changes coupled with the level of SO2. Clinical evaluation was performed during intraoperative measurements during tumor surgery (n = 10) and stereotactic deep brain stimulation implantations (n = 20). The LDF and DRS systems were also successfully assessed in the neurointensive care unit for a patient treated for SAH. The cerebral autoregulation was studied by relating the parameters from the optical systems to signals from the standard monitoring equipment in neurointensive care. In summary, the presented work takes DRS and LDF one step further toward clinical use for optical monitoring of cerebral microcirculation.

Indiana University-Purdue University Indianapolis (IUPUI) / The purpose of this prospective, observational study was to determine if a technique used to detect early signs of small-fiber neuropathy (local skin heating) could detect signs of small-fiber taxane-induced peripheral neuropathy (TIPN) in breast cancer survivors (BCS) during the first 6 weeks of Taxol®. Aims of the study were to compare the mean size of (1) axon reflexes and (2) axon flares (both markers of small fiber nerve function) in BCS receiving Taxol® to the size of reflexes/flares in healthy female controls (HCs). A third aim was to determine whether the size of axon reflexes/flares correlated with (a) overall TIPN severity and (b) severity of individual signs/symptoms of TIPN during early Taxol®. Data for the study was collected from nine BCS and 20 HCs (N = 29). All BCS had first-time, non-metastatic cancer and received weekly or bi-weekly Taxol®. Data was collected at 3 time-points: Time 1 (day 0, before Taxol®), Time 2 (day 14), and Time 3 (day 42). Axon reflexes and flares were generated using a validated 40-minute skin heating protocol. Axon reflexes were measured using laser Doppler Flowmetry. Axon flares were measured using full-field laser perfusion imaging. TIPN was measured using the 5-item Short Form of the Total Neuropathy Score (Reduced Version). Results identified potential signs of small-fiber TIPN in BCS after 6 weeks of Taxol®. Contrary to expectation, axon reflexes were larger for BCS at Time 3 than HCs, suggesting that Taxol® may be associated with an increase in small-fiber nerve function like that seen in pre-clinical studies. Clinical signs/symptoms of TIPN were not significantly correlated with axon reflexes or axon flares at the same time point. Analyses of axon flare size were confounded by issues with the data. These results add to the growing body of evidence showing that Taxol® affects small-diameter sensory nerves and provides the first evidence in humans that changes in small-fiber nerve function may be detectable after just 6 weeks of Taxol® therapy. Studies in larger samples are needed to validate these findings.