58 - Prognostic Utility of Neuroimaging in Infants with Cramped Synchronized General Movements

Publication Number: 1051.58

Santina Zanelli, University of Virginia, Charlottesville, VA, United States; Presley S. Volkema, Valley Health, Winchester, VA, United States; Lisa Letzkus, University of Virginia School of Medicine, Earlysville, VA, United States; Kristen Heinan, University of Virginia Medical Center, Charlottesville, VA, United States; Marcus Hook, University of Virginia School of Medicine, Charlottesville, VA, United States; David A. Joyner, University of Virginia School of Medicine, Charlottesville, VA, United States; Mark R. Conaway, University of Virginia School of Medicine, Charlottesville, VA, United States

Background: Early detection of cerebral palsy (CP) is critical to improve outcome. The presence of cramped synchronized general movements (CSGM) on the General Movement Assessment (GMA) is associated with increased CP risk. While brain MRI is the gold-standard for detailed evaluation of brain abnormalities, it is expensive, may require sedation, and is challenging to interpret. Head ultrasound (HUS), a more accessible and cost-effective modality, represents a potential alternative. Enlarged subarachnoid space (ESS), measurable by sinocortical width (SCW) has been suggested as a potential surrogate marker of white matter volume loss. Whether ESS is present in infants with CSGM is unknown, as is the prognostic utility of HUS vs. brain MRI in these infants.

Objective: To assess the reliability of SCW measurement on HUS, compare ESS detection on HUS vs. MRI, and evaluate the association between ESS and neurodevelopmental outcomes, including CP, in infants with CSGM.

Design/Methods: We conducted a single-center, retrospective study in a level IV NICU, of all infants with CSGM from 2019-2024. SCW on HUS at term-corrected age was measured by 4 readers and ESS was defined as SCW >3.5 mm (Fig. 1). MRI were scored using the Kidokoro scoring system. Infants were followed for up to age 24 months to assess neurodevelopmental outcomes. Pearson correlations and standard methods using ANOVA on the random rater model were used to assess the intra- and inter-rater reliability.

Results: 23 infants were included (mean gestational age of 26.4±3.4 weeks; mean birth weight of 947.4±527.9g, Table 1). ESS was identified in 47.8% and 60.9% of cases on HUS and MRI, respectively with concordance in 73% of cases (Table 2). Intra- and inter-rater reliability for SCW measurement was excellent (r = 0.957-0.996 and 0.896-0.953, respectively). Additional MRI abnormalities were detected in the majority of cases, though most patient had normal or mild global brain scores (Table 2). Follow-up data was available in 17 patient (74%) and a neurodevelopmental impairment was identified in 76.5% of patients (Table 2). Patients with ESS on HUS had a CP diagnosis in 62.5% of cases vs. 44.4% of cases in patients with dilated CSF spaces on brain MRI.

Conclusion(s): ESS is common in infants with CSGM, and most have abnormal neurodevelopmental outcomes. While MRI identified anomalies in more patients with CSGM, it was not superior to ESS on HUS in identifying those who went on to have a diagnosis of CP. These results suggests that ESS on HUS may be clinically useful in identifying patients at risk for CP. Work is ongoing to confirm these findings in a larger cohort.

Cohort Demographics
Table 1_demographics.pdfGA- gestational age; HUS - head ultrasound; IVH - intraventricular hemorrhage

Neuroimaging and follow-up results
Table 2_neuroimaging_ESS_FINAL.pdfASD - autism spectrum disorder; CSF - cerebral spinal fluid; CP - cerebral palsy; ESS - enlarged subarachnoid space (defined as sinocortical width > 3.5 mm); HUS - head ultrasound; MRI - magnetic resonance imaging; NDI - neurodevelopmental impairment

Measurement of sinocortical width on head ultrasound
Panel A: Linear coronal view of a head ultrasound obtained at 44 weeks postmenstrual age (PMA) in an infant born at 25 5/7 weeks illustrating normal sinocortical width (SCW, 0.99 mm). Panel B: Linear coronal image of a head ultrasound obtained at 35 6/7 weeks PMA in an infant born at 25 6/7 weeks illustrating enlargement of the subarachnoid space with a SCW of 6.23 mm. Of note, all the measurement of SCW were obtained at the level of the foramen of Monro for standardization.