Radiological Features And Clinical Treatment In Idiopathic Normal Pressure Hydrocephalus

Part? Feasibility of simple linear measurements to determine ventricular enlargement in patients with idiopathic normal pressure hydrocephalus Objective: To evaluate the feasibility and reproducibility of linear measurements for determining ventricular enlargement in patients with idiopathic normal pressure hydrocephalus(i NPH)and their correlation to ventricular volume(VV).Methods: Pre-operative brain computed tomography(CT)scans were retrospectively evaluated in 36 patients with i NPH.The quantitative markers of Evan's index(EI),VV,frontal and occipital horn ratio(FOR),modified cella media index(m CMI),third ventricular width(TVW),temporal horn width(TPH),frontal horn width(FHW)in coronal plane,and callosal angle(CA)at the posterior commissure(PC)were independently measured by a neurosurgeon and a radiologist.Intraclass correlation coefficients(ICC)were calculated to establish inter-rater agreement among the reviewers.Pearson's correlation coefficients were used to assess the relationship of each linear measurement with total VV.Results: The overall inter-rater agreement among reviewers was almost perfect for EI,VV,FOR,m CMI,TVW,substantial for FHW in coronal plane and moderate for TPH and CA at PC.Pearson correlation coefficients showed excellent correlation between m CMI and VV.Moderate correlation were found between the VV and FHW,TVW,FOR,EI and CA at PC.Fair correlation was found between the VV and TPH.Conclusion: Simple linear measurements could serve as effective alternative to volumetric analysis to determine ventricular size in patients with i NPH.The quantitative marker of m CMI is more reasonable and accurate than factors of EI,FOR and other simple linear measurements.Part ? Feasibility of radiological markers in idiopathic normal pressure hydrocephalus Objective: Various radiological markers have been proposed for diagnostics in idiopathic normal pressure hydrocephalus(i NPH).We examined the usefulness of radiological markers in the diagnostics and prediction of shunt response in i NPH Methods: Pre-operative brain computed tomography(CT)scans were retrospectively evaluated in 68 patients with i NPH.The CT twelve imaging features investigated were the Evans index(EI)?Frontal-occipital horn ratio(FOR)?Modified cella media index(m CMI)Frontal horn width(FHW)?Temporal horn width(TPH)?Third ventricular width(TVW)?callosal angle(CA)at the posterior commissure(PC)?Dilation of the Sylvian fissure(DSF)?Narrow cerebrospinal fluid space at high convexity and high midline(Narrow CSF space at HC/M)?Disproportionately enlarged subarachnoid space hydrocephalus(DESH)?Periventricular hyperintensities(PVH)?Focally dilated sulci(FDS).In logistic regression models,with shunt outcome as a dependent variable,the ORs for the independent variables with imaging features.Results: In logistic regression models,DESH?Narrow CSF space at HC/M?CA at PC?TVW were significant(P<.05),both in univariate analyses and when adjusted for.age,sex,diabetes and hypertension Conclusion: DESH?Narrow CSF space at HC/M?CA at PC?TVW are common in patients with idiopathic normal pressure hydrocephalus and were significant predictors of a positive shunt outcome.These noninvasive and easily assessed radiologic markers could aid in the selection of candidates for shunt surgeryPart ? Changes of the volume of the ventricles and midbrain size following VP shunt in idiopathic normal-pressure hydrocephalus Objective: The purpose of the study was to investigate the correlation between midbrain or ventricular volume(VV)and classic clinical triad of symptoms in patients with Idiopathic normal pressure hydrocephalus(INPH),including dementia,urinary incontinence,and gait disturbance.Methods: Brain computed tomography(CT)scan was performed and clinical symptoms were assessed before and 1 year after surgery in 26 patients with gait improvement of INPH.Classic clinical triad of symptoms were assessed by the Timed Up and Go test,the i NPH Grading Scale and Montreal Cognitive Assessment(MOCA)Beijing Version,a validated assessment tool for i NPH symptoms.Anteroposterior,left-to-right diameter and cross-sectional areas of the midbrain were measured at the inferior collicular level of axial images in CT.Ventricular volume was measured using 3D Slicer in axial images CT.Intraclass correlation coefficients(ICC)were calculated to establish inter-rater agreement among the reviewers.Spearman's correlation was used for correlation analyses.Paired,two-tailed Student'st test was used for comparison of baseline and postoperative values of each measurement.Results: Clinical follow-up was assessed 1 year after shunt surgery.The change rates of the ventricular volume showed a significant correlation with changes in scores of the total i NPHGS,scores for the gait domain in the i NPHGS,and change rates related to time of turn around in the TUG test.Change rates in the Anteroposterior,left-toright diameter and cross-sectional areas of the midbrain did not show a significant correlation with changes in clinical parameters Conclusion: The decrease in ventricular volumes was significantly correlated with clinical improvement.In this study there were no findings to suggest involvement of the midbrain in the manifestation of gait disturbance in i NPH.