Cerebral Hemodynamic and Metabolic Abnormalities in Neonatal Hypocalcemia: Findings from Advanced MRI.

Background and purpose: Neonatal hypocalcemia is the most common metabolic disorder, and whether asymptomatic disease should be treated with calcium supplements remains controversial. We aimed to quantify neonatal hypocalcemia's global CBF and cerebral metabolic rate of oxygen (CMRO₂) using physiologic MR imaging and elucidate the pathophysiologic vulnerabilities of neonatal hypocalcemia.

Materials and methods: A total of 37 consecutive patients with neonatal hypocalcemia were enrolled. They were further divided into subgroups with and without structural MR imaging abnormalities, denoted as neonatal hypocalcemia-a (n = 24) and neonatal hypocalcemia-n (n = 13). Nineteen healthy neonates were enrolled as a control group. Brain physiologic parameters determined using phase-contrast MR imaging, T2-relaxation-under-spin-tagging MR imaging, and brain volume were compared between patients with neonatal hypocalcemia (their subgroups) and controls. Predictors for neonatal hypocalcemia-related brain injuries were identified using multivariate logistic regression analysis and expressed as ORs with 95% CIs.

Results: Patients with neonatal hypocalcemia showed significantly lower CBF and CMRO₂ compared with controls. Furthermore, the neonatal hypocalcemia-a subset (versus controls or neonatal hypocalcemia-n) had significantly lower CBF and CMRO₂. There was no obvious difference in CBF and CMRO₂ between the neonatal hypocalcemia-n subset and controls. CBF and CMRO₂ were independently associated with neonatal hypocalcemia. The ORs were 0.80 (95% CI, 0.65-0.99) and 0.97 (95% CI, 0.89-1.05) for CBF and CMRO₂, respectively.

Conclusions: Neonatal hypocalcemia with structural damage may exhibit lower hemodynamics and cerebral metabolism. CBF may be useful in assessing the need for calcium supplementation in asymptomatic neonatal hypocalcemia to prevent brain injury.