scholarly journals Validation of noninvasive photoacoustic measurements of sagittal sinus oxyhemoglobin saturation in hypoxic neonatal piglets

2018 ◽  
Vol 125 (4) ◽  
pp. 983-989 ◽  
Author(s):  
Jeeun Kang ◽  
Emad M. Boctor ◽  
Shawn Adams ◽  
Ewa Kulikowicz ◽  
Haichong K. Zhang ◽  
...  

We hypothesize that noninvasive photoacoustic imaging can accurately measure cerebral venous oxyhemoglobin saturation (So2) in a neonatal model of hypoxia-ischemia. In neonatal piglets, which have a skull thickness comparable to that of human neonates, we compared the photoacoustic measurement of sagittal sinus So2 against that measured directly by blood sampling over a wide range of conditions. Systemic hypoxia was produced by decreasing inspired oxygen stepwise (i.e., 100, 21, 19, 17, 15, 14, 13, 12, 11, and 10%) with and without unilateral or bilateral ligation of the common carotid arteries to enhance hypoxia-ischemia. Transcranial photoacoustic sensing enabled us to detect changes in sagittal sinus O2 saturation throughout the tested range of 5–80% without physiologically relevant bias. Despite lower cortical perfusion and higher oxygen extraction in groups with carotid occlusion at equivalent inspired oxygen, photoacoustic measurements successfully provided a robust linear correlation that approached the line of identity with direct blood sample measurements. Receiver-operating characteristic analysis for discriminating So2 <30% showed an area under the curve of 0.84 for the pooled group data, and 0.87, 0.91, and 0.92 for hypoxia alone, hypoxia plus unilateral occlusion, and hypoxia plus bilateral occlusion subgroups, respectively. The detection precision in this critical range was confirmed with sensitivity (87.0%), specificity (86.5%), accuracy (86.8%), positive predictive value (90.5%), and negative predictive value (81.8%) in the combined dataset. These results validate the capability of photoacoustic sensing technology to accurately monitor sagittal sinus So2 noninvasively over a wide range and support its use for early detection of neonatal hypoxia-ischemia. NEW & NOTEWORTHY We present data to validate the noninvasive photoacoustic measurement of sagittal sinus oxyhemoglobin saturation. In particular, this paper demonstrates the robustness of this methodology during a wide range of hemodynamic and physiological changes induced by the stepwise decrease of fractional inspired oxygen to produce hypoxia and by unilateral and bilateral ligation of the common carotid arteries preceding hypoxia to produce hypoxia-ischemia. This technique may be useful for diagnosing risk of neonatal hypoxic-ischemic encephalopathy.

Cureus ◽  
2018 ◽  
Author(s):  
Lexian J McBain ◽  
Joe Iwanaga ◽  
Rod J Oskouian ◽  
Marios Loukas ◽  
R. Shane Tubbs

Circulation ◽  
2014 ◽  
Vol 129 (suppl_1) ◽  
Author(s):  
Steven C Masley ◽  
Richard Roetzheim ◽  
Timothy P McNamara ◽  
Lucas V Masley ◽  
Douglas D Schocken

Introduction: Cardiovascular disease (CVD) remains the number one cause of mortality in the western world. Carotid intimal media thickness (carotid IMT) is a safe and reliable predictor of future CVD risk. Hypothesis: The study aims to assess the hypothesis that lifestyle factors impact carotid IMT, and determine which nutrition and fitness risk factors best predict mean carotid IMT scores. Methods: A prospective cross-sectional analysis of 592 men and women undergoing health and cardiovascular risk screening. This study reflects the first visit of these subjects, age 23 to 65 (mean = 48.2), who are followed longitudinally and who were participants at a “wellness” oriented program for patients who are generally well-educated and mostly in good health. Measurements were made of fitness using VO2max stress testing and push-up and sit-up scores following the American College of Sports Medicine testing protocols, diet intake using a 3-day dietary intake survey and computerized analyses. Mean carotid IMT scores were obtained using high resolution B-mode ultrasonography of the common carotid arteries. Each subject had ≥10 images collected from the far wall of the right and left distal 1 cm of the common carotid arteries at end diastole. The carotid intimal thickness was measured as a continuous variable, using both multivariate linear and bivariate linear regression. Multivariate analyses adjusted for potential confounders using multiple linear regression and included measures of body composition, blood pressure, fasting lipid and glucose levels, and statin use. Results: Multivariate analyses show that higher mean carotid IMT values are associated with increasing age (p<0.0001), male gender (p<.0.0001), lower aerobic capacity (p=0.0045), lower intake of fish (p=0.05), and lower intake of zinc (p=0.0002). Bivariate analyses controlling for age and gender, with and without statin use, showed higher mean carotid IMT scores were statistically associated with lower levels of aerobic fitness, (p = 0.0007), lower intake of fiber (p=0.02) and lower intake of magnesium (p=0.019). Intake of protein, carbohydrate, and fat as percent of calories; as well as intake of saturated fat, sodium, calcium, potassium, and vitamin K; measures of strength (assessed with push-up and sit-up testing); and self-reported exercise minutes per week were not associated with mean carotid IMT scores. Conclusions: In this database, aerobic fitness and dietary intake of fiber, fish, magnesium, and zinc are associated with lower carotid IMT scores. Further studies are warranted to explore the impact of emerging lifestyle factors on cardiovascular risk and clinical outcomes.


2017 ◽  
Vol 17 (2) ◽  
pp. 95-101 ◽  
Author(s):  
Mohamed Ibrahim ◽  
Bushra Hussein A. Malik ◽  
Moawia Gameraddin

1992 ◽  
Vol 114 (1) ◽  
pp. 147-149 ◽  
Author(s):  
C. G. Caro ◽  
C. L. Dumoulin ◽  
J. M. R. Graham ◽  
K. H. Parker ◽  
S. P. Souza

The blood flow in arteries affects both the biology of the vessels and the development of atherosclerosis. The flow is three dimensional, unsteady, and difficult to measure or to model computationally. We have used phase-shift-based magnetic resonance angiography to image and measure the flow in the common carotid arteries of a healthy human subject. There was curvature of the vessels and thin-slice dynamic flow imaging showed evidence of the presence of secondary motions. Flexing the cervical spine straightened the vessels and reduced the asymmetry of the flow.


2015 ◽  
Vol 120 (10) ◽  
pp. 982-988
Author(s):  
Abolhassan Shakeri ◽  
Mojtaba Varshochi ◽  
Naser Atapour ◽  
Masoud Nemati ◽  
Manoochehr Khoshbaten ◽  
...  

2020 ◽  
Author(s):  
Jeeun Kang ◽  
Raymond C. Koehler ◽  
Shawn Adams ◽  
Ernest M. Graham ◽  
Emad M. Boctor

AbstractWe present a light-emitting diode (LED)-based transcranial photoacoustic measurement (LED-trPA) of oxyhemoglobin (HbO2) saturation at superior sagittal sinus (SSS) in hypoxic neonatal piglets. The optimal LED imaging wavelengths and frame averaging scheme were determined based on in vivo characterization of transcranial sensitivity. Based on the framework (690/850 nm with >20 frame averaging), graded hypoxia was successfully identified in neonatal piglets in vivo with less than 10.0 % of root mean squared error (RMSE). This preclinical study suggests the feasibility of a rapid, cost-effective, and safe LED-trPA monitoring of perinatal hypoxia-ischemia and prompt interventions for clinical use.


2015 ◽  
Vol 12 (3) ◽  
pp. 30-33
Author(s):  
L V Melnikova ◽  
L F Bartosh ◽  
O A Grechishkina

Aim. To study changes in structural and functional features of the common carotid arteries and central hemodynamic parameters under the influence of fosinopril at hypertensive patients depending on achieving target blood pressure.Material and methods. The study included 116 patients with essential hypertension. All patients underwent a general clinical study, an ultrasound scan of the common carotid arteries (CCA ) with the assessment of the structure and intravascular blood flow, and echocardiography with the definition of the parameters of central hemodynamic and intravascular, ambulatory blood pressure monitoring (ABPM) before the study and after 24 weeks of antihypertensive therapy angiotensin - converting enzyme fosinopril. Two groups of patients: the first group consisted of 74 people with the achievement of the targets of blood pressure (BP), the second 42 people who have not been achieved target BP levels.Results. In the first group there was a statistically significant decrease in the proportion of peripheral resistance, increased systolic index, distensibility coefficient of the common carotid arteries peak flow velocity. In the second group specific peripheral resistance was significantly increased, the thickness of the intima-media increased, decreased peak flow velocity.Conclusion. Effectiveness depends on fosinopril initial state total peripheral resistance, cardiac output, structural and functional features elastic arteries.


2020 ◽  
Vol 39 (1) ◽  
pp. 79-84
Author(s):  
Oluwagbemiga O. Ayoola ◽  
Rahman A. Bolarinwa ◽  
Oluwatoyin H. Onakpoya ◽  
Stephen O. Onigbinde ◽  
Christianah M. Asaleye ◽  
...  

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