Dataset Information

Quantification of whole-brain oxygenation extraction fraction and cerebral metabolic rate of oxygen consumption in adults with sickle cell anemia using individual T₂ -based oxygenation calibrations.

ABSTRACT:

Purpose

To evaluate different T₂ -oxygenation calibrations for estimating venous oxygenation in people with sickle cell anemia (SCA).

Methods

Blood T₂ values were measured at 3 T in the internal jugular veins of 12 healthy volunteers and 11 SCA participants with no history of stroke, recent transfusion, or renal impairment. T₂ -oxygenation relationships of both sickled and normal blood samples were calibrated individually and compared with values generated from published models. After converting venous T₂ values to venous oxygenation, whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen were calculated.

Results

Sickle blood samples' oxygenation values calculated from our individual calibrations agreed well with measurements using a blood analyzer, whereas previous T₂ calibrations based on normal blood samples showed 13%-19% underestimation. Meanwhile, oxygenation values calculated from previous grouped T₂ calibration for sickle blood agreed well with experimental measurement on averaged values, but showed up to 20% variation for several individual samples. Using individual T₂ calibrations, the whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen of SCA participants were 0.38 ± 0.08 and 172 ± 42 µmol/min/100 g, respectively, which were comparable to those values measured on healthy volunteers.

Conclusion

Our results confirm that sickle blood T₂ values not only depend on the hematocrit and oxygenation values, but also on other hematological factors. The individual T₂ calibrations minimized the effect of heterogeneity of sickle blood between different SCA populations and improved the accuracy of T₂ -based oximetry. The measured oxygen extraction fraction and cerebral metabolic rate of oxygen of this group of SCA participants were found to not differ significantly from those of healthy individuals.

SUBMITTER: Li W

PROVIDER: S-EPMC6879787 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Publications

Quantification of whole-brain oxygenation extraction fraction and cerebral metabolic rate of oxygen consumption in adults with sickle cell anemia using individual T<sub>2</sub> -based oxygenation calibrations.

Li Wenbo W Xu Xiang X Liu Peiying P Strouse John J JJ Casella James F JF Lu Hanzhang H van Zijl Peter C M PCM Qin Qin Q

Magnetic resonance in medicine 20190904 3

<h4>Purpose</h4>To evaluate different T<sub>2</sub> -oxygenation calibrations for estimating venous oxygenation in people with sickle cell anemia (SCA).<h4>Methods</h4>Blood T<sub>2</sub> values were measured at 3 T in the internal jugular veins of 12 healthy volunteers and 11 SCA participants with no history of stroke, recent transfusion, or renal impairment. T<sub>2</sub> -oxygenation relationships of both sickled and normal blood samples were calibrated individually and compared with values g ...[more]

PMID: 31483528

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