Purpose or Case Report: To assess cerebral blood flow (CBF) in pediatric patients before and after an acetazolamide (Diamox) challenge using a 3D pseudo-continuous arterial spin labeling (pCASL) pulse sequence with a spiral-in/out k-space trajectory.
Methods & Materials: Exams were performed on a 3T Ingenia MR platform from Philips Healthcare, utilizing a 32-channel head array. Four patients have been studied: Patient 1-an 8y old girl with Moyamoya disease, Patient 2-a 14y boy with neurofibromatosis 1 migraines, Patient 3-a 21y old girl with an optic glioma, and Patient 4-a 13 months male with suspected Moyamoya Disease.

Diamox dosages were 490 mg, 800 mg, 780 mg, and 142 mg, respectively, for the four patients. pCASL was performed twice, immediately before and 15 minutes after Diamox injection. Spiral raw data were reconstructed offline and quantitative CBF maps were generated. White and gray matters voxels were extracted using FSL and Matlab software and a CBF histogram of the whole-brain was computed.
Results: In Patient 1, time-of-flight (TOF) angiography demonstrated impaired flow in both the right middle cerebral (MCA) and internal carotid arteries (ICA). The Moyamoya patient exhibited very little CBF change in response to Diamox (pre- CBF average: 59.5 ml/100g/min, post- CBF average: 59.4 ml/100g/min), suggesting limited CBF reserve. In Patient 2, the response to Diamox was moderate, with mean CBF increasing from 42.7 to 56.0 ml/100g/min. TOF confirms a marked narrowing of the right MCA, and dynamic susceptibility contrast imaging further corroborates decreased CBF in the affected brain parenchyma. Patient 3 exhibited significant flow voids in the right distal MCA and ICA. The patient demonstrated significant increase in CBF in response to Diamox, from 28.9 to 49.8 ml/100g/min. Patient 4 exhibited a 12% increase in CBF after Diamox administration. pCASL results corroborate TOF findings of narrowed MCA, ICA, and anterior cerebral artery.
Conclusions: 3D spiral pCASL provides a clinically useful quantitative approach to assess CBF in pediatric patients.