Katya Rozovsky MD, Presenter: Nothing to Disclose

Enrique C. G. Ventureyra, Abstract Co-Author: Nothing to Disclose

Jorge Davila, Abstract Co-Author: Nothing to Disclose

Elka Miller MD, Abstract Co-Author: Nothing to Disclose

Fast brain MRI imaging is a promising study for young children that require anesthesia. Initially, it was used for shunt assessment, but now it is successfully used for nonhydrocephalic indications. Most common protocols use T2 weighted sequences with very short acquisition time (20-40 seconds). The advantages of this method, including avoiding the need to obtain CT images and/or sedating the child for an MRI, are widely described in neurosurgical literature. However, the poor contrast resolution and the use of a type of pulse; carries potential pitfalls and limitations. Purpose: To review, analyze and document pitfalls and limitations of "fast" brain MRI in non-sedated children.  

50 T2 weighted "short sequence" studies were performed on 30 non-sedated pediatric patients (1day -5 years; mean: 18 months). Indications for the MRI included: status post shunt insertion/revision (n=11), follow up of shunt-dependent hydrocephalus (n=9), non-shunt postoperative follow-up (n=9), complications of prematurity (n=6), macrocephaly (n=5), congenital malformations (n=4), and follow up of isolated ventriculomegaly (n=6). The radiological findings and clinical charts were retrospectively reviewed by two pediatric radiologists. All "fast" MR studies were compared to the most recent MRI or CT study.

"Fast sequences" MRI provided a satisfactory practical answer to the clinical question in all cases. VP shunt position and ventricular size were properly evaluated. However, in 6/11 patients after shunt insertion there were additional undetected or underestimated pathological findings: undetected sinus vein thrombosis (n=1), subdural hematoma (n=5). In 2/9 postoperative cases there was limited differentiation between subarachnoid and subdural collections.

Radiologists reading "fast brain MRI’s" should be aware of the “weak points” of this study that can potentially alter the treatment strategy and be underestimated due to the type of imaging. Modification of the MR protocol should be considered for each individual case depending on the clinical indication.

Radiologists reading "fast brain MRI” for non sedated children need to be aware of the limitations of this sequence. Modification of the MR protocol should be considered for each individual case.

Rozovsky, K, Ventureyra, E, Davila, J, Miller, E, What the Radiologist Should Know about "Fast-Brain MRI" in Nonsedated Young Children: The Experience at Children's Hospital of Eastern Ontario.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11001139.html