Table 2.

MoCA scores and changes in MRI findings.

First Author, Year	Average MoCA Post-RT (Range, Bonus Point)	Pre-MRI Findings	Post-MRI Findings	Study Limitations
Ma Q, 2016 [36]	24.2 (22–27)		45 altered FC compared to untreated NPC group	Heterogeneous treatment protocol, combined both non-irradiated and irradiated subjects, varied sample size, lack of new and larger sample, and between-subject variance
Qiu Y, 2017 [29]	NR	Functional network connectivity for NPC patients pre- and post-RT shared similar connectivity	Weaker intra-network connectivity with lower mean connectivity correlation than baseline	Heterogeneous treatment protocols, between-subject variance
Ma Q, 2017 [42]	24.2 (22–27)		Altered FC between cerebellar seeds and relative brain clusters	Heterogeneous treatment protocol, combined both non-irradiated and irradiated subjects, varied sample size, lack of new and larger sample, and between-subject variance
Guo Z, 2018 [40]	<26	No differences in cerebral volume of pre-NPC to controls	Decrease in brain macrostructural volume	Combined both non-irradiated and irradiated subjects, short time interval, and varied sample size
Lv X, 2018 [41]	NR	No significant differences in volumes of hippocampus and hippocampal subfields between groups	Significant volume reductions in bilateral hippocampus and hippocampal subfields	Combined both non-irradiated and irradiated subjects and varied sample size
Ren WT, 2019 [39]	27 (24–29)	No significant changes in regional cerebral and connectivity before RT	Reduced regional cerebral and neural network functions	Comparison to healthy controls and small sample size, short time interval
Wu G, 2020 [37]	<26 (<12 years education and >65 years age)	Baseline of kurtosis and diffusivity does not show significant difference	Significantly lower kurtosis and diffusivity of white matter	Heterogeneous treatment protocols, comparison between different marker groups, and between subject-variance