Voxel-based analysis of the metabolic asymmetrical and network patterns in hypermetabolism-associated crossed cerebellar diaschisis

Crossed cerebellar diaschisis (CCD) has been widely investigated in patients with supratentorial hypometabolism, however, the available evidence about the metabolic feature of CCD in patients with contralateral supratentorial hypermetabolism is lacking. This study aimed to assess the metabolic asymmetrical profile, network pattern and predisposing factors for the hypermetabolism-associated CCD, by using voxel-based asymmetry index (AI) and brain network analyses. Seventy CCD positive (CCD+) and 99 CCD negative (CCD-) patients with unilateral supratentorial hypermetabolism were introduced. Among different brain regions with AI(max) or AI(min), striatum & thalamus was accompanied by the highest positive rate of CCD (85.7% or 70.1%, respectively). CCD+ group had significantly greater AI(max) (median [IQR], 0.62 [0.44–0.84] vs. 0.47 [0.35–0.61]), supratentorial hypermetabolic volume (1183.5 [399.3–3026.8] vs. 386.0 [152.0–1193.0]) and hypometabolic volume (37796.5 [24741.8–53278.0] vs. 3337.0 [1020.0–17193.0]), and lower AI(min) (−0.85 [-1.05–−0.73] vs. −0.49 [−0.68–−0.35]) compared with CCD- group (all P < 0.001). Logistic regression analysis manifested that patients with AI(min) located at striatum & thalamus were 16.4 times more likely to present CCD than those at frontal lobe (OR = 16.393; 95% CI, 4.463–60.207; P < 0.001), and the occurrence of CCD was also associated with AI(max) (OR = 49.594; 95% CI, 5.519–445.653; P < 0.001) and AI(min) (OR = 3.133 × 10(−4), 95% CI, 1.693 × 10(−5)–5.799 × 10(−3), P < 0.001). Brain network analysis indicated that the relative hypermetabolism in the contralateral supplementary motor cortex (SMC) and precuneus gyrus were constant in the CCD related patterns. These results demonstrated that the greater AI(max), lower AI(min) and AI(min) located at striatum & thalamus should be predisposing factors for CCD in patients with unilateral supratentorial hypermetabolism. Relative increased activities in the contralateral SMC and precuneus gyrus might be attributed to a compensatory mechanism for the abnormal brain network related to CCD.