Ultra-low-field portable MRI for assessing ventricular size in pediatric hydrocephalus: a feasibility study

Hydrocephalus, characterized by abnormal CSF accumulation, poses diagnostic and management challenges, especially in pediatric patients. Timely and accurate diagnosis is crucial for effective treatment. The aim of this study was to investigate the feasibility of using ultra-low-field portable MRI (pMRI) as a supplementary tool for assessing ventricular caliber and radiographic features of hydrocephalus, rather than as a stand-alone diagnostic modality.

A single-blind prospective design across three tertiary care centers evaluated the ultra-low-field pMRI for determination of ventricular size in patients with a diagnosis of hydrocephalus or ventriculomegaly. Participants undergoing MRI using standardized protocols were consecutively recruited from neurosurgery and pediatric neurology clinics as well as the emergency department. Radiographic features were collected from both experimental and standard imaging modalities to assess ventricular morphology and diagnose hydrocephalus. The study adhered to ethical guidelines, ensuring participant privacy, confidentiality, and informed consent, with rigorous protection of protected health information and compliance with HIPAA regulations.

A total of 153 patients were enrolled, 53.59% of whom were male and 46.4% were female. The mean age was 9.55 ± 6.39 years. Etiologies were most commonly posthemorrhagic (27.45%), myelomeningocele (15.03%), or aqueductal stenosis (15.03%). Bland-Altman plots showed near congruent agreement between pMRI and standard of care for the Evans index and frontal occipital horn ratio (FOHR). Lin's concordance correlation coefficient showed substantial agreement between pMRI and standard-of-care imaging for both Evans index (0.922, 95% CI 0.8941-0.9428) and FOHR (0.9419, 95% CI 0.9206-0.9576).

This study highlights the promise of low-field pMRI machines in assessing ventricular size and morphology in pediatric patients. However, pMRI should not be viewed as a stand-alone diagnostic modality for hydrocephalus but rather as a complementary tool in managing specific aspects of the condition. Further research is needed to optimize pMRI use in pediatric neuroimaging, but the accessibility, safety, and diagnostic accuracy of low-field MRI suggest that it could become a valuable addition to current imaging tools.