scholarly journals Differences in Microstructural Alterations of the Hippocampus in Alzheimer Disease and Idiopathic Normal Pressure Hydrocephalus: A Diffusion Tensor Imaging Study

2010 ◽  
Vol 31 (10) ◽  
pp. 1867-1872 ◽  
Author(s):  
Y.J. Hong ◽  
B. Yoon ◽  
Y.S. Shim ◽  
A.H. Cho ◽  
S.C. Lim ◽  
...  
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Andreas Eleftheriou ◽  
Ida Blystad ◽  
Anders Tisell ◽  
Johan Gasslander ◽  
Fredrik Lundin

AbstractIdiopathic normal pressure hydrocephalus (iNPH) is a disorder with unclear pathophysiology. The diagnosis of iNPH is challenging due to its radiological similarity with other neurodegenerative diseases and ischemic subcortical white matter changes. By using Diffusion Tensor Imaging (DTI) we explored differences in apparent diffusion coefficient (ADC) and fractional anisotropy (FA) in iNPH patients (before and after a shunt surgery) and healthy individuals (HI) and we correlated the clinical results with DTI parameters. Thirteen consecutive iNPH-patients underwent a pre- and post-operative clinical work-up: 10 m walk time (w10mt) steps (w10ms), TUG-time (TUGt) and steps (TUGs); for cognitive function MMSE. Nine HI were included. DTI was performed before and 3 months after surgery, HI underwent DTI once. DTI differences analyzed by manually placing 12 regions-of-interest. In patients motor and balance function improved significantly after surgery (p = 0.01, p = 0.025). Higher nearly significant FA values found in the patients vs HI pre-operatively in the thalamus (p = 0.07) accompanied by an almost significant lower ADC (p = 0.08). Significantly FA and ADC-values were found between patients and HI in FWM (p = 0.02, p = 0.001) and almost significant (p = 0.057) pre- vs postoperatively. Postoperatively we found a trend towards the HIs FA values and a strong significant negative correlation between FA changes vs. gait results in the FWM (r = −0.7, p = 0.008). Our study gives a clear indication of an ongoing pathological process in the periventricular white matter, especially in the thalamus and in the frontal white matter supporting the hypothesis of a shunt reversible thalamo-cortical circuit dysfunction in iNPH.


2019 ◽  
Vol 33 (1) ◽  
pp. 66-74
Author(s):  
Irene Grazzini ◽  
Francesco Redi ◽  
Karima Sammartano ◽  
Gian Luca Cuneo

Purpose Diffusion tensor imaging is a magnetic resonance technique that provides information about the orientation and anisotropy of the white matter tracts. The aim of this study was to analyse diffusion tensor imaging quantitative parameters in idiopathic normal pressure hydrocephalus patients, in order to determine whether this method could correlate to clinical scores and cerebrospinal fluid flowmetry data. Methods and materials Fifteen consecutive patients with idiopathic normal pressure hydrocephalus and 15 age-matched controls underwent cerebrospinal fluid flowmetry and diffusion tensor imaging using a 1.5 Tesla system. Fractional anisotropy, mean diffusivity, axial diffusivity and radial diffusivity values were calculated using region of interest atlas-based tract-mapping in nine cerebral areas and compared among the two groups. In addition, for idiopathic normal pressure hydrocephalus patients, diffusion tensor imaging parameters were correlated to clinical scores (mini mental state examination and frontal assessment battery) and cerebrospinal fluid flowmetry data. Results Mean fractional anisotropy was significantly lower for the idiopathic normal pressure hydrocephalus group than for the control group in the forceps minor and motor cortex; the idiopathic normal pressure hydrocephalus group had significantly higher mean axial diffusivity for the genu of the corpus callosum and forceps minor. We did not find significant correlation between diffusion tensor imaging parameters and cerebrospinal fluid flowmetry and mini mental state examination, while we observed a correlation between forceps minor fractional anisotropy and frontal assessment battery; no correlation between flowmetry and clinical scores was found. Conclusion Our findings suggest that diffusion tensor imaging provides a non-invasive biomarker of white matter changes in idiopathic normal pressure hydrocephalus patients. Forceps minor is the best site to analyse. As diffusion tensor imaging offers a better correlation to clinical status than cerebrospinal fluid flowmetry, it should be included in the routine idiopathic normal pressure hydrocephalus protocol.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Hajime Yokota ◽  
Arvind Vijayasarathi ◽  
Milos Cekic ◽  
Yoko Hirata ◽  
Michael Linetsky ◽  
...  

Purpose. To investigate the pathological change of the glymphatic system in idiopathic normal pressure hydrocephalus (iNPH) using diffusion tensor imaging (DTI) analysis. Materials and Methods. 24 right-handed patients were referred to our hydrocephalus clinic for assessment of ventriculomegaly and gait impairment. 12 of 24 were diagnosed as pseudo-iNPH (piNPH) based on assessment by a neurologist. Diffusivity maps in the direction of the x-axis (right-to-left) (Dx), y-axis (anterior-to-posterior) (Dy), and z-axis (inferior-to-superior) (Dz) were computed. The diffusion map was coregistered to International Consortium for Brain Mapping (ICBM) DTI-81 atlas. The analysis along the perivascular space (ALPS) index was defined as mean (Dxpro, Dypro)/mean (Dypro, Dzasc), where Dxpro and Dxasc are Dx values in the projection and association fiber areas, respectively. Evans index and callosal angle were also assessed on each case. Results. ALPS indexes of the control, piNPH, and iNPH cases were 1.18 ± 0.08, 1.08 ± 0.03, and 0.94 ± 0.06, respectively, and there were significant differences among the groups (control vs. piNPH, P = 0.003; control vs. iNPH P < 0.001; piNPH vs. iNPH, P < 0.001). Area under curve (AUC) was 0.92, 1.00, and 1.00 on control vs. piNPH, control vs. iNPH, and piNPH vs. iNPH on ROC analysis. Between piNPH and NPH, ALPS index has higher diagnostic performance than Evans index and callosal angle (AUC = 1.00 vs. 0.84, P = 0.028; AUC = 1.00 vs. 0.74, P = 0.016). Conclusion. Atlas-based ALPS index using the DTI method differentiated among iNPH, piNPH, and controls clearly.


2020 ◽  
pp. 197140092097515
Author(s):  
Irene Grazzini ◽  
Duccio Venezia ◽  
Gian Luca Cuneo

Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome that comprises a triad of gait disturbance, dementia and urinary incontinence, associated with ventriculomegaly in the absence of elevated intraventricular cerebrospinal fluid (CSF) pressure. It is important to identify patients with iNPH because some of its clinical features may be reversed by the insertion of a CSF shunt. The diagnosis is based on clinical history, physical examination and brain imaging, especially magnetic resonance imaging (MRI). Recently, some papers have investigated the role of diffusion tensor imaging (DTI) in evaluating white matter alterations in patients with iNPH. DTI analysis in specific anatomical regions seems to be a promising MR biomarker of iNPH and could also be used in the differential diagnosis from other dementias. However, there is a substantial lack of structured reviews on this topic. Thus, we performed a literature search and analyzed the most recent and pivotal articles that investigated the role of DTI in iNPH in order to provide an up-to-date overview of the application of DTI in this setting. We reviewed studies published between January 2000 and June 2020. Thirty-eight studies and four reviews were included. Despite heterogeneity in analysis approaches, the majority of studies reported significant correlations between DTI and clinical symptoms in iNPH patients, as well as different DTI patterns in patients with iNPH compared to those with Alzheimer or Parkinson diseases. It remains to be determined whether DTI could predict the success after CSF shunting.


Sign in / Sign up

Export Citation Format

Share Document