Maria Vittoria Spampinato, M.D Presentation No. eP-171 Fast Brain Magnetic Resonance Imaging for Non-Hydrocephalic Indications Gustavo M. Cervantes, M.D; Milad Yazdani, M.D; Thomas Larrew, M.D; Ramin Eskandari, M.D; Maria Vittoria Spampinato, M.D

Background Fast Brain MRI (FBMRI) Ultrafast T2-weighted technique utilizing HASTE (Half-Fourier Acquisition Single-Shot Turbo Spin-Echo) single pulse fast acquisition sequences to acquire axial, coronal and sagittal T2WI for the rapid brain evaluation of pediatric patients. By far, the most common indication for FBMRI in the pediatric population is for hydrocephalus or shunt follow up evaluation. Nevertheless, referral from providers to evaluate their patients for non-hydrocephalic indications are consistently increasing at our institution. 1. Overlap of imaging appearances often exists between CNS toxoplasmosis and PCNSL. Degree of overlap and variability makes differentiating the two disorders increasingly difficult. 2-3. SWI could identify a much higher frequency of hemorrhagic changes in such lesions, as SWI has proven to be significantly more sensitive than conventional MRI sequences in recognizing hemorrhagic lesions in various disorders. Accordingly to the American Academy of Neurology, a diagnostic stereotactic brain biopsy is warranted when a HIV/AIDS patient has two or more ring-enhancing lesions and failures to respond clinically and on radiographic imaging after 7-14 days. Of if there is a solitary lesion with negative IgG toxoplasma gondii serology.

Purpose Fast Brain MRI (FBMRI) To assess the performance of FBMRI in the pediatric population referred for indications other than known hydrocephalus or VP shunt follow up, by evaluating the following factors: Need for additional routine MR imaging of the brain due to equivocal findings on the FBMRI. MR sequence quality using a 5-point scoring system. Review of (fast or routine) brain MRI studies performed before or after the current FBMRI.

Material and Methods Retrospective IRB approved study Inclusion criteria Fast Brain MRI (FBMRI) Age: Pediatric patients (0-18 years old) Indication: Non-hydrocephalus conditions Study period: 14 months Exclusion criteria: History of known hydrocephalus or (VP) shunt procedure. FBMRI protocol obtained with the addition of non-T2 HASTE sequences (e.g. T1WI, FLAIR, DWI/ADC).

Material and Methods FBMRI quality assessment One reader assessment of a 5-point scoring system based on evaluation of all FBMRI sequences accordingly to: Overall degree of motion degradation artifacts Overall diagnostic quality of major anatomic details 1 Non-diagnostic Indiscernible anatomic details 2 Moderate motion Limited quality, multiple slices are degraded 3 Mild motion Good quality, not many slices degraded 4 Slight motion Very good quality, slight motion on few slices 5 No motion Excellent quality, no motion

Total no. FBMRI: 234 For all conditions and population ages Results Total no. FBMRI: 234 For all conditions and population ages Pediatric Non-hydrocephalus FBMRI n = 49 Imaging workup Only FBMRI available: 26/49 (51%) Additional imaging available: 24/49 (49%) *Required further routine MRI assessment n = 4/49 (8%) * No. of patients required to obtain a routine MRI the brain to assess for equivocal findings detected on the FBMRI.

Results Patient data 32 male and 17 female patients average age: 3 years old (0 m – 14 yo) 1 out of 49 FBMRI order was from the ER. a 11 yo girl who came for evaluation of possible development of hydrocephalus after head trauma, craniofacial fractures and epidural hematoma. 48/49 were for routine evaluation. 2 out of 49 patients required general anesthesia for the FBMRI. 47/49 required no sedation. a 2 month old infant and a 2 year old (31 months old) child.

Results Most common indications and results for the FBMRI Total FBMRI Indications (n = 49) 19 Macrocephaly 6 Epidural hematoma 4 Subdural hematoma 3 Arachnoid cyst Chiari 1 Germinal matrix hemorrhage 2 Dandy-Walker Total FBMRI Results (n = 49) 11 Normal brain Benign enlargement of the subarachnoid spaces 6 Subdural hematoma 5 Epidural hematoma 4 Chiari 1 3 Benign brain cysts 2 Arachnoid cyst Others: 1. 4th ventricle ependymoma 1. Asymmetry of lateral ventricles 1. Cerebellar hypoplasia 1. Cerebritis 1. Colloid cyst 1. Colpocephaly 1. Lumbar spine malformation 1. Meningocele 1. Pseudomeningocele Others: 1. Germinal matrix hemorrhage 1. Infectious cerebellitis 1. Lipoma of the scalp 1. Periventricular leukomalacia 1. Post-op, 4th ventricle ependymoma 1. Post-op, traumatic brain injury 1. Rhomboencephalosynapsis

Results FBMRI Quality Assessment Based on a 5-point visual scoring system % FBMRI Exams (n=49) FBMRI Quality Categories

T2 HASTE Imaging axial, coronal and sagittal planes, rating score: 5 (excellent quality) TR: 2000 ms; TE: 81 ms; DFOV 150 mm; 5mm slice thk/6mm gap; acquisition time 4 minutes

T2 HASTE Imaging axial, coronal and sagittal planes, rating score: 2 (limited quality) TR: 2000 ms; TE: 81 ms; DFOV 150 mm; 5mm slice thk/6mm gap; acquisition time 4 minutes

Results 4 out 49 (8%) FBMRIs had shown equivocal findings. Routine follow-up brain MRI confirmed the equivocal abnormality on the FBMRI, and more accurately suggested the diagnosis.

Results 4 diagnosis were incompletely evaluated out of the 49 FBMRIs and required a routine brain MRI for clarification. Asymmetric temporal horn enlargement with heterogeneous T2 signal. Routine brain MRI confirmed the presence of intraventricular blood products, and a mass lesion was excluded. Bilateral extra-axial hematomas of indeterminate age. Routine brain MRI confirmed the diagnosis of extra-axial hematomas and revealed additional presence of subarachnoid blood products. Incomplete division of the cerebellar hemispheres. Routine brain MRI confirmed rhombencephalosynapsis and additional evidence of partial absence of the vermis. Left posterior scalp thickening without evidence of meningocele. Routine brain MRI demonstrated lipoma of the scalp.

Results FBMRI was deemed of very good to excellent quality in 68% of the studies 22% of the FBMRI had a good quality score 10% of the FBMRI had limited quality score 0 studies were non-diagnostic

Conclusion In our series, FBMRI was appropriate for rapid evaluation of nonhydrocephalus conditions. Most common conditions sought for FBMRI Macrocephaly, epidural and subdural hematoma, arachnoid cyst, Chiari I, Dandy-Walker and germinal matrix hemorrhage Most common results: Normal brain and benign enlargement of the subarachnoid spaces Follow up full brain MRI protocol was needed in 8% of the cases. In 51% of the cases, FBMRI represented the entire imaging work up and no additional studies were deemed necessary.

References Niederhauser BD et al. Retrospective review of rapid pediatric brain MR imaging at an academic institution including practice trends and factors affecting scan times. AJNR Am J Neuroradiol. 2013 Sep;34(9):1836-40 Missios S et al. Quick-brain magnetic resonance imaging for nonhydrocephalus indications. J Neurosurg Pediatr. 2008 Dec;2(6):438-44. O'Neill BR et al. Rapid sequence magnetic resonance imaging in the assessment of children with hydrocephalus. World Neurosurg. 2013 Dec;80(6):e307-12. Patel DM et al. Fast-sequence MRI studies for surveillance imaging in pediatric hydrocephalus. J Neurosurg Pediatr. 2014 Apr;13(4):440-7. Rozovsky K et al. Fast-brain MRI in children is quick, without sedation, and radiation-free, but beware of limitations. J Clin Neurosci. 2013 Mar;20(3):400-5.