Portable MRI for Pediatric Hypoxic Ischemic Brain Injury

Standard brain magnetic resonance imaging (MRI) is the gold-standard to diagnose acute ischemic brain injuries; however, it is not always feasible to obtain this standard MRI due to risks and contraindications. Some of the most common risks can include transport to the radiology department, especially with critically ill patients on life-saving medical devices, exposure to ionizing radiation, and contraindications can include incompatible surgical hardware in patients' bodies, amongst others.

Our institution has an FDA-cleared portable MRI (pMRI) by Hyperfine Research, Inc. (HRI). This device addresses many of the conventional MRI challenges by:

1. Operating at very low magnetic field strengths strength (less than 0.2 T or approximately 10 times less than the field strength of conventional devices) and eliminating the need for special rooms or shielding. Family members and staff can remain at the patient's bedside.
2. Minimizing conditions such as claustrophobia and anxiety with an open concept, transparent "helmet" to rest the head in during the exam.
3. Portable and can maneuver through hospital environments and wheeled directly to a patient's bedside.
4. Noise levels are substantially lower than conventional MRI systems, so hearing protection is optional for the patient. The sounds are described as vibrations that produce rhythmic tones.

• Portable MRI (Device): Enrolled subjects will undergo a portable, ultralow-field MRI (pMRI) at the bedside in the ICU location within +/- 24 hours of a clinically obtained, conventional MRI and/or head CT
• Scavenged Sample Collection (Other): Remaining blood or cerebrospinal fluid samples from clinical testing will be scavenged at timepoints correlating to the radiology imaging.

Primary outcomes

• Determine the sensitivity and specificity of pMRI for detection of acute pediatric focal ischemic brain injuries. [During intensive care admittance, an average of 1 month]: Perform pMRI on pediatric ICU patients within +/- 24 hours of a clinically obtained, conventional MRI. Compare detection rates and severity of ischemia and cerebral edema by pMRI vs conventional MRI to determine sensitivity and specificity.
• Establish the sensitivity and specificity of pMRI relative to head CT for detection of cerebral edema and ischemic brain injury in critically ill patients deemed unstable for standard MRI. [During intensive care admittance, an average of 1 month]: Perform pMRI on pediatric ICU patients within +/- 24 hours of a clinically obtained, conventional head CT obtained for acute neurologic changes. Compare detection rates and severity of cerebral edema and ischemia by pMRI vs head CT to establish sensitivity and specificity.
• Calculate the sensitivity and specificity of pMRI for detection of acute pediatric global hypoxic-ischemic brain injuries [During intensive care admittance, an average of 1 month]: Perform pMRI on pediatric ICU patients within +/- 24 hours of a clinically obtained, conventional MRI that demonstrates acute global hypoxic-ischemic brain injury as read by a clinical neuroradiologist. Compare detection rates and severity of acute global hypoxic-ischemic brain injury by pMRI vs conventional MRI to calculate sensitivity and specificity.

Secondary outcomes

• Assess the association of imaging findings and rates of clinical neurologic events [From ICU admission until final neuroimaging during active study participation]: The rate of seizures, pupillary changes, focal neurologic deficits, and other clinical neuromonitoring data will be assessed for correlation to and type of acute brain injury diagnosed on neuroimaging.

Sex: All, ages: any to 17 Years

Inclusion Criteria:

* Patients hospitalized in the Pediatric Intensive Care Unit, Cardiac Intensive Care Unit, or the Neonatal Intensive Care Unit
* Ages 0-17 years at study enrollment
* Acute neurologic deficit suspected secondary to Hypoxic Ischemic Brain Injury (HIBI) or patients at high risk for HIBI

Exclusion Criteria:

* Pregnancy
* Any patient who has a contraindication to having an MRI

Patients with a passive or active implant will:

* First be reviewed on MRISafety.com to determine MR conditionality
* If the device is listed as Conditional or Unsafe for a 1.5T or a 3T, the device will then be reviewed by the MRI Safety Officer or MRI Physician Section chief to determine true conditionality for the portable MRI

• Jessica S Wallisch, MD, Principal investigator, Children's Mercy Kansas City