Demonstration of periventricular brain motion during a Valsalva maneuver: description of technique, evaluation in healthy volunteers and first results in hydrocephalic patients

There has long been a need for a sensitive and predictive parameter in the evaluation of hydrocephalic patients. Our goal was to assess ventricular re sponse to a Valsalva maneuver as a potential method of studying patients wi th hydrocephalus. Twenty-five healthy volunteers and 5 patients with commun icating hydrocephalus were examined with an axial and 10 volunteers with an axial, coronal and sagittal true fast imaging steady precession (FISP) seq uence in a 1.5-T clinical MR scanner (TR 4.8 ms, TE 2.3 ins, flip angle 70 degrees, slice thickness 5 mm, field of view 330 mm, 3 slices). Images were assessed both as dynamic images in cine mode and by measuring lateral vent ricular size over time. All volunteers showed marked periventricular brain motion. The lateral ventricular area was reduced under the Valsalva maneuve r by an average of 18% (SD 7) in healthy volunteers, while remaining practi cally constant in the patient group. Differences were statistically signifi cant with a p < 0.0001. The Valsalva maneuver leads to periventricular brai n motion, which can be consistently detected by a true FISP sequence. Our m ethod proved to be an easy and reliable method with a capacity to identify hydrocephalic patients.