CO_(2)BOLD assessment of moyamoya syndrome:Validation with single photon emission computed tomography and positron emission tomography imaging

AIM To compare the assessment of cerebrovascular reserve(CVR) using CO_2 BOLD magnetic resonance imaging(MRI) vs positron emission tomography(PET) and single photon emission computed tomography(SPECT) as reference standard.METHODS Ten consecutive patients(8 women, mean age of 41 ± 26 years) with moyamoya syndrome underwent 14 presurgical evaluations for external-internal carotid artery bypass surgery. CVR was assessed using CO_2 BOLD and PET(4)/SPECT(11) with a maximum interval of 36 d, andevaluated by two experienced neuroradiologists.RESULTS The inter-rater agreement was 0.81 for SPECT(excellent), 0.43 for PET(fair) and 0.7 for CO_2 BOLD(good). In 9/14 cases, there was a correspondence between CO_2 BOLD and PET/SPECT. In 4/14 cases, CVR was over-estimated in CO_2 BOLD, while in 1/14 case, CVR was underestimated in CO_2 BOLD. The sensitivity of CO_2 BOLD was 86% and a specificity of 43%. CONCLUSION CO_2 BOLD can be used for pre-surgical assessment of CVR in patients with moyamoya syndrome and combines the advantages of absent irradiation, high availability of MRI and assessment of brain parenchyma, cerebral vessels and surrogate CVR in one stop.