gms | German Medical Science

Objective: Modern hydrodynamic theories of hydrocephalus discuss CSF flow obstruction or disturbance of pulsatility as etiological factors for the development of hydrocephalus. Standard-MRI images are designed to detect brain tissue but not CSF space abnormalities. High-resolution (HR) MRI is a powerful tool to detect obstructive pathology in the CSF compartment. This study compares HR-T2 to standard T2 sequences regarding the detection rate of CSF pathway obstructions.

Method: We examined MRI scans of 56 children with hydrocephalus diagnosed within first year of life. Median age at time of MRI was 27,5 months, range 0 months –17 y. Standard multiplanar 3 mm T2-sequences were assessed and compared to multiplanar 1 mm true-fisp (n=49), CISS (n=2) and HR-T2 (n=5) sequences obtained at the same time. A senior neuroradiology (TN) and pediatric-neurosurgery consultant (MUS) rated 112 imaging series blinded and randomized.

Results: TN found obstructions in 51 children with standard and in 56 children with HR-MRI (p<0.05). MUS found obstructions in 40 children with standard and in 56 children with HR-MRI (p<0.05) The total number of obstruction sites in standard-T2 was 188 and 107 compared to 383 and 362 in HR-MRI according to TN and MUS respectively (p<0.005). Considerably more obstructions were detected at the aqueduct, the foramen of Luschkae and the basal cisterns.

Conclusions: HR-MRI classified all cases of pediatric hydrocephalus as obstructive in nature, with a 2–3 fold higher detection rate. Especially outflow obstruction from the 4^th ventricle and basal cistern obstruction could be visualized well. HR-MRI should become standard in diagnostic hydrocephalus imaging.