Differentiation of normal pressure hydrocephalus from hypoxico-ischemic patients by the quantitative analysis of PC-MRI of the CSF at the aqueduct of Sylvius Poster No.: C-0418 Congress: ECR 2012 Type: Authors: Keywords: DOI: Scientific Exhibit J. Forner Giner 1, R. Sanz-Requena 1, N. Florez 2, L. Martí- Bonmatí 1 ; 1 Valencia/ES, 2 Bucaramanga/CO Neuroradiology brain, Head and neck, Computer applications, MR, Diagnostic procedure, Computer Applications-Detection, diagnosis, CAD, Cerebrospinal fluid, Dementia, Hemodynamics / Flow dynamics 10.1594/ecr2012/C-0418 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 7
Purpose Normal pressure hydrocephalus (NPH) is clinically comprised of dementia, gait instability and urinary incontinence (Hakim triad). It can be potentially treated with ventricular shunting, but it is difficult to diagnose accurately, as many conventional MRI findings can either be found in NPH or small vessel cerebrovascular disease (CVD) (ventricular dilatation, white matter infarcts). Furthermore, there is not a gold standard diagnosis for NPH. The aim of this work is to evaluate if the quantitative assessment of PC-MR images can help to discriminate between initial and established and NPH and CVD patients. Methods and Materials 37 patients were included in the study and classified into CVD (19) or NPH (28) using clinical and follow up criteria (acute/progressive or insidious/fluctuating disease course, cognitive impairment, ataxia, cardiovascular risk factors and response to ventricular derivation). NPH patients were further separated into initial (15) or established (13), following a conventional MRI-derived score system, taking into account Evans index, flow void at the aqueduct of Sylvius and normal/increased subarachnoid space. All patients underwent a single-slice PC-MRI study with transversal location to the aqueduct (figure 1). A fixed encoding velocity of 15 cm/s was used and any aliasing artefacts were automatically corrected during the post-processing stage. The aqueduct was semi-automatically segmentated, taking into account the laminar profile of the CSF fluid velocity, so that the central part of the aqueduct was used to calculated fluid velocity and the whole aqueduct was used to calculate flow (figure 2). Finally, CSF systolic and diastolic velocities, mean flow and stroke volume were calculated at the aqueduct of Sylvius. ANOVA tests were performed to assess differences among the groups. Images for this section: Page 2 of 7
Fig. 1: Slice location for the phase-contrast MR sequence Page 3 of 7
Fig. 2: Square ROI for the automatic detection of the aqueduct of Sylvius on a morphological image (left) and a PC image (right). Page 4 of 7
Results Figure 3 shows an example of a flow curve for a NPH patient. Mean flow and stroke volume showed excellent statistical significance to separate initial and established NPH from CVD patients (p<0.001 in all post-hoc comparisons) with less than 15% overlap. Obtained values for mean flow were 5.6±2.0, 14.1±4.5 and 22.9±4.9 ml/min for CVD, initial NPH and established NPH, respectively. Values for stroke volume were 40.4±14.5, 114.0±41.3 and 167.2±39.8 µl for CVD, initial NPH and established NPH, respectively. Images for this section: Fig. 3: Flow curve for a NPH patient. Page 5 of 7
Conclusion Quantitative PC-MRI is a useful tool for an objective early diagnosis of NPH patients and the differential diagnosis from patients with CVD brain changes. References Hakim S, Adams RD. The special clinical problem of symptomatic hydrocephalus with normal cerebrospinal fluid pressure. Observations on cerebrospinal fluid hydrodynamics. J Neurol Sci 1965;2:307-27. Florez YN, Moratal D, Forner J et al. Semiautomatic analysis of phase contrast magnetic resonance imaging of cerebrospinal fluid flow through the aqueduct of Sylvius. Magn Reson Mater Phy 2006;19:78-87. Relkin N, Marmarou A, Klinge P, et al. Diagnosing idiopathic normal-pressure hydrocephalus. Neurosurgery 2005;57:4-16. Bradley W. Normal pressure hydrocephalus and deep white matter ischemia: which is the chicken and which is the egg? AJNR Am J Neuroradiol 2001;22:1638-40. Bradley W. idiopathic normal pressure hydrocephalus: new findings and thoughts on etiology. AJNR Am J Neuroradiol 2008;29:1-3. Luetmer P, Huston J, Friedman J et al. Measurement of cerebrospinal fluid flow at the cerebral aqueduct by use of phase-contrast magnetic resonance imaging: technique validation and utility in diagnosing idiopathic normal pressure hydrocephalus. Neurosurgery 2002;50:534-43. Personal Information Contact information: Dr. Roberto Sanz-Requena Page 6 of 7
E-mail: rsanz.val@quiron.es www.cuantificacionquironvalencia.es Page 7 of 7