Date of Award

January 2023

Document Type

Thesis

Degree Name

Medical Doctor (MD)

Department

Medicine

First Advisor

Sam Payabvash

Abstract

Background: Transcranial ultrasound and magnetic resonance imaging (MRI) are both commonly used for evaluating brain structures and intracranial pathologies in neonatal intensive care units (NICUs). While transcranial ultrasound can identify certain conditions, MRI is considered more sensitive in detecting white matter disease. However, MRI has traditionally only been performed in term-equivalent infants that can be safely transferred to the MRI suite. A new 1-Tesla Embrace® point-of-care brain MRI technology has received FDA approval, enabling safe imaging in the NICU.Purpose: The purpose of the study is to evaluate the use of a point-of-care 1-Tesla MRI for evaluation of brain pathology of neonates and to compare the findings to other imaging technologies. Methods: Clinical findings and point-of-care 1-Tesla MRI imaging findings of patients in neonatal intensive care units (NICUs) were retrospectively reviewed and assessed over a year and a half at a single institution. These findings were compared to other imaging modalities and a greater discussion over the feasibility of the technology is also incorporated into the manuscript. Results: A total of 60 neonates underwent a point-of-care 1-Tesla MRI scan, with an average gestational age at scan time of 38.5 ± 2.3 weeks. 53 (88%) of the infants had additional brain imaging available for comparison, including transcranial ultrasound (n=46), 3-Tesla MRI (n=3), or both (n=4). The most common reasons for the 1-Tesla MRI scan were term corrected age scan for extremely preterm neonates (42%), intraventricular hemorrhage follow-up (33%), and suspected hypoxic injury (18%). The 1-Tesla scan could identify ischemic lesions in two infants with suspected hypoxic injury, which were confirmed by 3-Tesla MRI. However, two lesions were identified by 3-Tesla MRI that were not visualized on 1-Tesla scan. Nevertheless, 1-Tesla MRI could detect parenchymal microhemorrhages not seen on ultrasound. Seven (12%) patients had no other brain imaging available for comparison with the 1-Tesla scan. One of the 1-Tesla scans was prematurely terminated due to motion but was still included in the evaluation. Conclusion: Although limited by field strength, pulse sequences, and patient weight (4.5 kg)/head circumference (38 cm) restrictions, the Embrace® point-of-care 1-Tesla MRI can identify clinically relevant intracranial pathologies in infants within a NICU setting.

Comments

This thesis is restricted to Yale network users only. This thesis is permanently embargoed from public release.

Download

Share

COinS