PhD Scientific Days 2022

Clinical Medicine V. (Poster discussion will take place in the Aula during the Coffee Break)

The predictive value of MRI scoring systems for neurodevelopmental outcome in infants with hypoxic ischemic encephalopathy

Text of the abstract

Introduction: Several MRI scoring systems are used to quantify brain injury in infants with hypoxic-ischemic encephalopathy (HIE). The Barkovich score system relies on conventional MRI sequences to assess injury in the basal ganglia, thalamus and watershed areas. Recently, Weeke et al. has developed a scoring system assessing brain injury of grey matter, white matter, cortex and cerebellum using diffusion weighted images (DWI) and proton magnetic resonance spectroscopy (H-MRS).

Aims: Our objective was to compare the predictive value of two MRI scoring systems for adverse outcome (severe disabilities or death) in infants receiving hypothermia for HIE.

Method: This single center retrospective cohort study included infants who received hypothermia for HIE between 2013 and 2019. Post-rewarming brain MRI images were evaluated according to the two MRI scoring systems developed by Barkovich (total score 9) and Weeke et al. (total score 55). Follow-up was performed using Bayley- II Scales of Infant Development at 18-24 months of age. Adverse outcome was defined as death or severe disabilities if Bayley II score was  70 in any domain. Receiver Operating Characteristics (ROC) curve was used to calculate area under the curve (AUC), with the DeLong- test for comparison of AUCs.

Results: A total of 163 infants were included. The rate of death was 5.6% and severe disabilities occurred in 27.3% (44/162) of the cases. MRI studies were carried out at a median 4.7 days of life [IQR 3.5; 6.2]. Brain injury was detected with higher frequency using Weeke score compared to Barkovich (71% vs. 35%, p0.001). The area under the ROC curve was 0.81 [95%CI 0.74; 0.88] with the optimal cutoff point of 12 (Sensitivity 57%, Specificity 93%) for adverse outcome using the Weeke score. The AUC was 0.73 [95%CI 0.66; 0.81] with the optimal cutoff point of 2 (Sensitivity 57%, Specificity 88%) based on the Barkovich score. DeLong- test showed a significant difference between the two AUCs (p= 0.0012).

Conclusion: Our findings confirm that a more detailed scoring system incorporating DWI and H-MRS has a better predictive value for adverse outcome in infants with HIE. MRI can serve as a bridging biomarker and a surrogate end point for neurodevelopmental outcome, so it is crucial to quantify brain injuries based on standardized scoring systems.

Funding: ÚNKP-21-4-II-SE-12