Bicaudate Ratio Research Articles

Differences in Brain Atrophy Pattern between People with Multiple Sclerosis and Systemic Diseases with Central Nervous System Involvement Based on Two-Dimensional Linear Measures.

Conventional brain magnetic resonance imaging (MRI) in systemic diseases with central nervous system involvement (SDCNS) may imitate MRI findings of multiple sclerosis (MS). In order to better describe the MRI characteristics of these conditions, in our study we assessed brain volume parameters in MS (n = 58) and SDCNS (n = 41) patients using two-dimensional linear measurements (2DLMs): bicaudate ratio (BCR), corpus callosum index (CCI) and width of third ventricle (W3V). In SDCNS patients, all 2DLMs were affected by age (CCI p = 0.005, BCR p < 0.001, W3V p < 0.001, respectively), whereas in MS patients only BCR and W3V were (p = 0.001 and p = 0.015, respectively). Contrary to SDCNS, in the MS cohort BCR and W3V were associated with T1 lesion volume (T1LV) (p = 0.020, p = 0.009, respectively) and T2 lesion volume (T2LV) (p = 0.015, p = 0.009, respectively). CCI was associated with T1LV in the MS cohort only (p = 0.015). Moreover, BCR was significantly higher in the SDCNS group (p = 0.01) and CCI was significantly lower in MS patients (p = 0.01). The best predictive model to distinguish MS and SDCNS encompassed gender, BCR and T2LV as the explanatory variables (sensitivity 0.91; specificity 0.68; AUC 0.86). Implementation of 2DLMs in the brain MRI analysis of MS and SDCNS patients allowed for the identification of diverse patterns of local brain atrophy in these clinical conditions.

Predictive value of brain atrophy, serum biomarkers and information processing speed for early disease progression in multiple sclerosis.

Multiple sclerosis (MS) is a chronic autoimmune-mediated demyelinating disease of the central nervous system (CNS). A clinical presentation of the disease is highly differentiated even from the earliest stages of the disease. The application of stratifying tests in clinical practice would allow for improving clinical decision-making including a proper assessment of treatment benefit/risk balance. This prospective study included patients with MS diagnosed up to 1 year before recruitment. We analyzed serum biomarkers such as CXCL13, CHI3L1, OPN, IL-6, and GFAP and neurofilament light chains (NfLs); brain MRI parameters of linear atrophy such as bicaudate ratio (BCR), third ventricle width (TVW); and information processing speed were measured using the Symbol Digit Modalities Test (SDMT) during the 2 years follow-up. The study included a total of 50 patients recruited shortly after the diagnosis of MS diagnosis (median 0 months; range 0-11 months), and the mean time of observation was 28 months (SD = 4.75). We observed a statistically significant increase in the EDSS score (Wilcoxon test: Z = 3.06, p = 0.002), BCR (Wilcoxon test: Z = 4.66, p < 0.001), and TVW (Wilcoxon test: Z = 2.84, p = 0.005) after 2 years of disease. Patients who had a significantly higher baseline level of NfL suffered from a more severe disease course as per the EDSS score (Mann-Whitney U-test: U = 107, Z = -2,74, p = 0.006) and presence of relapse (Mann-Whitney U-test: U = 188, Z = -2.01, p = 0.044). In the logistic regression model, none of the parameters was a significant predictor for the achieving of no evidence of disease activity status (NEDA). In the model considering all assessed parameters, only the level of NfL had a significant impact on disease progression, measured as the increase in EDSS (logistic regression: β = 0.002, p = 0.017). We confirmed that NfL levels in serum are associated with more active disease. Moreover, we found that TVW at the time of diagnosis was associated with an impairment in cognitive function measured by information processing speed at the end of the 2-year observation. The inclusion of serum NfL and TVW assessment early in the disease may be a good predictor of disease progression independent of NEDA.

The value of ventricular measurements in the prediction of shunt dependency after aneurysmal subarachnoid hemorrhage

ObjectiveChronic hydrocephalus requiring shunt placement is a common complication of aneurysmal subarachnoid hemorrhage (SAH). Different risk factors and prediction scores for post-SAH shunt dependency have been evaluated so far. We analyzed the value of ventricle measurements for prediction of the need for shunt placement in SAH patients.MethodsEligible SAH cases treated between 01/2003 and 06/2016 were included. Initial computed tomography scans were reviewed to measure ventricle indices (bifrontal, bicaudate, Evans’, ventricular, Huckman’s, and third ventricle ratio). Previously introduced CHESS and SDASH scores for shunt dependency were calculated. Receiver operating characteristic analyses were performed for diagnostic accuracy of the ventricle indices and to identify the clinically relevant cut-offs.ResultsShunt placement followed in 221 (36.5%) of 606 patients. In univariate analyses, all ventricular indices were associated with shunting (all: p<0.0001). The area under the curve (AUC) ranged between 0.622 and 0.662. In multivariate analyses, only Huckman’s index was associated with shunt dependency (cut-off at ≥6.0cm, p<0.0001) independent of the CHESS score as baseline prediction model. A combined score (0–10 points) containing the CHESS score components (0–8 points) and Huckman’s index (+2 points) showed better diagnostic accuracy (AUC=0.751) than the CHESS (AUC=0.713) and SDASH (AUC=0.693) scores and the highest overall model quality (0.71 vs. 0.65 and 0.67), respectively.ConclusionsVentricle measurements are feasible for early prediction of shunt placement after SAH. The combined prediction model containing the CHESS score and Huckman’s index showed remarkable diagnostic accuracy regarding identification of SAH individuals requiring shunt placement. External validation of the presented combined CHESS-Huckman score is mandatory.

Identification of PMD subgroups using a myelination score for PMD.

The clinical spectrum of Pelizaeus-Merzbacher disease (PMD), a common hypomyelinating leukodystrophy, ranges between severe neonatal onset and a relatively stable presentation with later onset and mainly lower limb spasticity. In view of emerging treatment options and in order to grade severity and progression, we developed a PMD myelination score. Myelination was scored in 15 anatomic sites (items) on conventional T2-and T1w images in controls (n=328) and 28 PMD patients (53 MRI; n=5 connatal, n=3 transitional, n=10 classic, n=3 intermediate, n=2 PLP0, n=3 SPG2, n=2 female). Items included in the score were selected based on interrater variability, practicability of scoring and importance of scoring items for discrimination between patients and controls and between patient subgroups. Bicaudate ratio, maximal sagittal pons diameter, and visual assessment of midsagittal corpus callosum were separately recorded. The resulting myelination score consisting of 8 T2-and 5 T1-items differentiates patients and controls as well as patient subgroups at first MRI. There was very little myelin and early loss in severely affected connatal and transitional patients, more, though still severely deficient myelin in classic PMD, ongoing myelination during childhood in classic and intermediate PMD. Atrophy, present in 50% of patients, increased with age at imaging. The proposed myelination score allows stratification of PMD patients and standardized assessment of follow-up. Loss of myelin in severely affected and PLP0 patients and progressing myelination in classic and intermediate PMD must be considered when evaluating treatment efficacy.

Two-dimensional measurements with cut-off values are useful for assessing brain volume, physical disability, and processing speed in multiple sclerosis

BackgroundTwo-dimensional (2D) measures have been proposed as potential proxy measures for whole-brain volume in multiple sclerosis (MS); however, cut-off values that determine the degree of brain volume loss (BVL) have not been established. Since we had previously developed a system to categorize MS patients into clusters with significantly different degrees of BVL, we tried to identify cut-off values for 2D measurements that can discriminate MS patients on the basis of disease severity associated with brain atrophy. MethodsIn this cross-sectional analysis, ninety-one consecutive Japanese MS patients—clinically isolated syndrome (5%), relapsing-remitting MS (78%) and progressive MS (17%)—were categorized into two clusters (CL1 and CL2) with a significantly different degree of BVL using the method described in our previous study. MS patients were also evaluated for 2D measurements, namely, third ventricle width, lateral ventricle width (LVW), bicaudate ratio (BCR), and corpus callosum index (CCI). Thereafter, we performed receiver operating characteristic analysis to determine the cut-off values of the 2D measurements for categorizing the MS patients into two clusters. ResultsWe identified optimal cut-off values for each 2D measure with high specificity and sensitivity. The cut-off values for LVW, BCR, and CCI divided the MS patients into two subgroups, in which whole-brain and grey matter volume, EDSS, and processing speed were significantly different. ConclusionLVW, BCR, and CCI with particular cut-off values are useful to discriminate MS patients with decreased brain volume, physical disability, and processing speed.

Usefulness of two-dimensional measurements for the evaluation of brain volume and disability in multiple sclerosis.

BackgroundTwo-dimensional (2D) measures have been proposed as potential proxies for whole-brain volume in multiple sclerosis (MS).ObjectiveTo verify whether 2D measurements by routine MRI are useful in predicting brain volume or disability in MS.MethodsIn this cross-sectional analysis, eighty-five consecutive Japanese MS patients—relapsing-remitting MS (81%) and progressive MS (19%)—underwent 1.5 Tesla T1-weighted 3D MRI examinations to measure whole-brain and grey matter volume. 2D measurements, namely, third ventricle width, lateral ventricle width (LVW), brain width, bicaudate ratio, and corpus callosum index (CCI), were obtained from each scan. Correlations between 2D measurements and 3D measurements, the Expanded Disability Status Scale (EDSS), or processing speed were analysed.ResultsThe third and lateral ventricle widths were well-correlated with the whole-brain volume (p < 0.0001), grey matter volume (p < 0.0001), and EDSS scores (p = 0.0001, p = .0004, respectively).The least squares regression model revealed that 78% of the variation in whole-brain volume could be explained using five explanatory variables, namely, LVW, CCI, age, sex, and disease duration. By contrast, the partial correlation coefficient excluding the effect of age showed that the CCI was significantly correlated with the EDSS and processing speed (p < 0.0001).ConclusionVentricle width correlated well with brain volumes, while the CCI correlated well with age-independent (i.e. disease-induced) disability.

The Integrity of Retinal Morphology in Non-immunocompromised People Living with HIV on Antiretroviral Therapy.

Non-immunocompromised people living with HIV (NIPLHIV) share a similar immunocompetence to non-HIV (HIV) people with an elevated cluster of differentiation 4 (CD4) count in the era of antiretroviral therapy (ART). This has reduced the incidence of HIV retinopathy, thus raising the question of the integrity of the retinal morphology in NIPLHIV with longer life expectancy. The study assessed the retinal thickness and volume of NIPLHIV without retinitis on ART and attempted to find associations with linear parameters of cerebral atrophy. The study was conducted at a public hospital in South Africa. All people living with HIV were on ART with CD4 counts above 350 cells/mm3 and viral loads less than 10,000 copies/mL. The Heidelberg Spectralis ocular coherence tomographer assessed the retinal thickness and volume for comparison between 30 NIPLHIV and 30 HIV-negative participants. A subset of the HIV group obtained a computed tomography scan to determine the bicaudate ratio and the sylvian fissure ratio to assess cerebral atrophy. Independent t tests were performed to identify differences in retinal thickness and volume. Multivariate linear regressions measured associations between retinal thickness and volume with cerebral atrophy. The NIPLHIV group had a thicker mean global temporal subfields at Early Treatment Diabetic Retinopathy Study (ETDRS) 3 mm (P = .047) and ETDRS 6 mm (P = .03). The mean global temporal subfield volume at ETDRS 3 mm was also increased in the NIPLHIV group (P = .02). Nasal macula retinal nerve fiber layer thickness and the inferior inner nuclear layer macula volume were directly related to the bicaudate ratio, whereas the volumes at the outer retinal layer subfields of the macula were inversely related to sylvian fissure ratio in NIPLHIV. Macula thickness and volumetric differences do exist in NIPLHIV. Practitioners should keep NIPLHIV under retinal morphometric surveillance because they live longer. Associations of cerebral atrophy with retinal morphology may be used to monitor cerebral atrophy in NIPLIV on ART.

Activation-Induced Rigidity in Neurologically and Cognitively Healthy Individuals Aged 18-90 Years: A Cross-Sectional Study.

Rigidity is a key clinical feature of Parkinson's disease (PD), but in a very early phase of the disease it may be absent and can be enhanced through active movements of the arm contralateral to the one being tested. To evaluate in a large cohort of neurologically and cognitively healthy (NCH) subjects aged 18-90 years if activation-induced rigidity (AR) is present in all age classes, and if there are biological differences between subjects showing AR (AR+) and not showing AR (AR-). 2,228 NCH subjects categorized as young adult (18-44 years), adult (45-64 years), elderly (65-74 years), and old/oldest-old (75-90 years) were included in the analysis, and underwent brain MRI. White matter hyperintensities were assessed through two visual rating scales. Lacunes were also rated. Atrophy of the caudate nuclei and ventricular enlargement were assessed through the bicaudate ratio and the lateral ventricles to brain ratio. To elicit AR, the Froment's maneuver (FM) and the instructions of the UPDRS-ME were used. Among the sample, 1,689 (75.81%) subjects showed AR, of which 1,270 (57.00%) subjects showed AR by using FM, and 419 (18.81%) showed AR by using UPDRS-ME instructions. The latter subjects also showed AR by using FM. The number of AR+ subjects significantly increased with increasing age, regardless of the activation maneuver used. In each age class, the number of AR+ subjects was significantly higher by using the FM than the UPDRS-ME instructions. Our findings suggest that AR is likely to be one of the signs of the prodromal phase of PD.

APOE Genotypes and Brain Imaging Classes in Normal Cognition, Mild Cognitive Impairment, and Alzheimer's Disease: A Longitudinal Study.

To evaluate in 419 stroke-free cognitively normal subjects (CN) aged 45-82 years covering during a long prospective study (11.54 ± 1.47 years) the preclinical to dementia spectrum: 1) the distribution of small vessel disease (V) and brain atrophy (A) aggregated as following: V-/A-, V-/A+, V+/A-, V+/A+; 2) the relationship of these imaging classes with individual apolipoprotein E (APOE) genotypes; 3) the risk of progression to Alzheimer Disease (AD) of the individual APOE genotypes. Participants underwent one baseline (t0), and 4 clinical and neuropsychological assessments (t1,t2,t3, and t4). Brain MRI was performed in all subjects at t0, t2, t3 and t4.. White matter hyperintensities were assessed through two visual rating scales. Lacunes were also rated. Subcortical and global brain atrophy were determined through the bicaudate ratio and the lateral ventricle to brain ratio, respectively. APOE genotypes were determined at t0 in all subjects. Cox proportional hazard model was used to evaluate the risk of progression to AD. The imaging class of mixed type was very common in AD, and in non amnestic mild cognitive impaired APOE ε4 non carriers. In these subjects, frontal and parieto-occipital regions were most affected by small vessel disease. Our findings suggest that the APOE ε3 allele is probably linked to the brain vascular pathology.

Detrimental effects of hypercortisolism on brain structure and related risk factors

Brain structural abnormalities are often observed on magnetic resonance imaging (MRI) scans of Cushing's syndrome patients, but the pathogenesis is not fully understood. To understand the relationship between brain structural abnormalities and potential risk factors in active Cushing's disease (CD) patients, a total of 101 treatment-naïve CD patients and 95 sex-, age- and education matched controls with non-functioning adenomas (NFA) underwent clinical evaluation and MRI investigation, and the relative risk factors were analyzed. 14 patients in sustained remission after transsphenoidal surgery were followed. Compared with the NFA subjects, the patients with CD had more cortical (P < 0.01) and subcortical atrophy (P < 0.01) and a higher prevalence of white matter hyperintensity (WMH) (P < 0.01). WMH severity in CD patients positively correlated with age (r = 0.532, P = 0.000), disease course (r = 0.257, P = 0.009), postprandial glucose (r = 0.278, P = 0.005), frequency of left ventricular hypertrophy (r = 0.398, P = 0.001) and hypothyroidism (r = 0.246, P = 0.014). The markers of cortical and subcortical atrophy (sylvian fissure ratio, bifrontal ratio, bicaudate ratio and third ventricle width) were positively associated with the progression of WMH in the CD patients. In the follow-up of 14 patients with CD, brain atrophy and WMH was partially reversible after correction of hypercortisolism. In conclusions, brain atrophy and WMH were more likely to appear in CD patients and were possibly partially reversible following correction of hypercortisolism.

Subcortical Atrophy and Motor Outcomes in Pallidal Deep Brain Stimulation for Parkinson Disease

Appropriate patient selection is critical for successful deep brain stimulation (DBS) for Parkinson disease (PD). Subcortical atrophy is a possible determinant of postoperative DBS outcomes in patients with idiopathic PD, but it has not been well evaluated for DBS of the globus pallidus interna (GPi). We investigated perioperative subcortical atrophy measures in patients with PD and their relationship to postoperative motor response in bilateral GPi-targeted DBS. A retrospective cohort study examined correlations among indices of subcortical volumetry, disease duration, and age with postoperative outcomes at 6 months (Unified Parkinson's Disease Rating Scale Part III motor score quotient, levodopa equivalent daily dosing, and 39-item Parkinson's Disease Questionnaire mobility subscore). Subcortical volumetry was assessed by bicaudate ratio, Evans index, and third ventricular width on perioperative imaging. Linear regression models established correlations between preoperative variables and postoperative outcomes. Data from 34 patients with PD who were treated with GPi-targeted DBS were evaluated. Age was found to exhibit statistically significant positive correlations with all 3 measures of subcortical atrophy (P ≤ 0.002). None of the measures correlated with disease duration. Only Evans index and third ventricular width correlated with preoperative medication response (P < 0.05). Age and all 3 measures of atrophy exhibited statistically significant correlations with Unified Parkinson's Disease Rating Scale Part III motor score quotient (P ≤ 0.01), but not with levodopa equivalent daily dosing or 39-item Parkinson's Disease Questionnaire motor subscores (P > 0.05). Perioperative age and subcortical atrophy as measured in this study correlated with motor responsiveness at 6 months postoperatively among patients receiving bilateral GPi-targeted DBS stimulation for PD.

QTc Prolongation in Patients with Dementia and Mild Cognitive Impairment: Neuropsychological and Brain Imaging Correlations.

The QTc interval is the electrocardiographic manifestation of ventricular depolarization and repolarization. This marker is often prolonged in acute and chronic neurological conditions. The cause of the cerebrogenic QT prolongation remains unclear. The aim of the study was to analyze the relation between QTc interval and the degree of cognitive impairment and structural brain imaging changes in patients with dementia and mild cognitive impairment (MCI). To this aim, 269 patients were screened, of whom 61 met one or more exclusion criteria. The remaining 208 patients (56 control subjects, 44 patients with MCI, and 108 with dementia) were recruited. Eighty-five patients using drugs causing prolongation of QT interval were further excluded. The QT interval was measured manually in all 12 leads by a single blinded observer, assuming the longest QT value adjusted for heart rate by using the Bazett's formula. All patients underwent a structural brain imaging and the following measures were obtained: the bicaudate ratio and the periventricular hyperintensity and deep white matter hyperintensity using the modified Fazekas scale. Prolonged QTc interval was prevalent in 1) patients with dementia, especially in those with moderate-severe degree; 2) subjects with impairment of praxis and attention, low functional status, and behavioral symptoms; 3) patients with global and temporal atrophy and with higher scores on the Fazekas or leukoaraiosis scales. Degenerative and vascular processes might play a main role in QTc interval prolongation because of the damage to brain areas involved in the control of the autonomic cardiac nervous system.

Bi-caudate ratio as a MRI marker of white matter atrophy in multiple sclerosis and ischemic leukocencephalopathy

BackgroundBrain atrophy measurement is now a cornerstone in basic neuro-imaging science. While assessment of white matter atrophy by visual inspection is subjective, volumetric approaches are time-consuming and not often feasible. Bi-caudate ratio represents a linear surrogate parameter of brain volume that can be derived from standard imaging sequences. This study highlights the value of the bi-caudate ratio (BCR) as a MRI marker of white matter atrophy in patients with multiple sclerosis and ischemic leukoencephalopathy and set a cut-off value to differentiate between patients with white matter atrophy and normal subjects.ResultsA total of 115 patients (54 males and 61 females) diagnosed with white matter leukoencephalopathy (MS in 51 patients and ischemic leukoencephalopathy in 64 patients) were included. Another group of 60 subjects with a normal white matter signal was recruited as a control group. BCR for the patient group ranged from 0.13 to 0.27 (mean (± SD) = 0.16 ± 0.02), while for the control group, it ranged from 0.05 mm to 0.13 (mean (± SD) = 0.09 ± 0.01). The difference between the two groups was statistically significant (P value < 0.001). A cut-off value of 0.13 was used to differentiate between the BCR in both patients and control groups with sensitivity, specificity, and accuracy of 99.2%, 100%, and 99%, respectively. The difference in BCR for patients diagnosed with MS and ischemic leukoencephalopathy was also statistically significant (P value < 0.001).ConclusionThe bi-caudate ratio represents a linear measurement of subcortical atrophy that can be useful as a surrogate marker of global supra-tentorial white matter atrophy instead of the usually performed visual and therefore subjective assessment. It is an easily obtained measure that can be performed without complex time-consuming volumetric studies. Our findings also revealed that the BCR is higher in patients with ischemic leukoencephalopathy than in patients with MS.

Abnormalities of brain imaging in patients after left ventricular assist device support following explantation

The potential impact of long-term left ventricular assist device (LVAD) support on the brain remains unclear. This study aimed to investigate cerebral microvascular damage in patients after long-term LVAD implantation using magnetic resonance imaging (MRI). We reviewed the medical records of patients after continuous-flow LVAD implantation in our hospital from 2006 to 2016, who underwent brain MRI after LVAD explantation for either transplantation or recovery. Age- and sex-matched healthy controls and patients with chronic heart failure (CHF) were collected from our pooled MRI database. The presence of cerebral microbleeds (CMBs) and cortical superficial siderosis and the severity of white matter hyperintensity (WMH) and cerebral atrophy were compared between patients with prior LVAD and 2 control groups. This study included 49 patients with prior LVAD, 49 healthy controls, and 45 patients with CHF. CMBs and cortical superficial siderosis were detected in 98% (p < 0.001) and 31% (p < 0.001) of patients with prior LVAD, respectively. The number of CMBs was higher in patients with prior LVAD than in the 2 control groups. The severity of the WMH was higher in patients with prior LVAD than in healthy controls but similar to that in patients with CHF. Quantitative analyses of cerebral atrophy revealed a significantly higher bicaudate ratio and cella media index in patients with prior LVAD than in the 2 control groups. Patients after long-term LVAD support showed a higher prevalence of CMBs and cortical superficial siderosis and more severe cerebral atrophy than did controls. These findings may indicate cerebral microvascular damages in long-term LVAD support patients.

Isolated, Subtle Neurological Abnormalities in Mild Cognitive Impairment Types.

Isolated, subtle neurological abnormalities (ISNA) are commonly seen in aging and have been related to cerebral small vessel disease (SVD) and subcortical atrophy in neurologically and cognitively healthy aging subjects. To investigate the frequency of ISNA in different mild cognitive impairment (MCI) types and to evaluate for each MCI type, the cross-sectional relation between ISNA and white matter hyperintensities (WMH), lacunes, caudate atrophy, and ventricular enlargement. One thousand two hundred fifty subjects with different MCI types were included in the analysis and underwent brain magnetic resonance imaging. WMHs were assessed through two visual rating scales. Lacunes were also rated. Atrophy of the caudate nuclei and ventricular enlargement were assessed through the bicaudate ratio (BCr) and the lateral ventricles to brain ratio (LVBr), respectively. Apolipoprotein E (APOE) genotypes were also assessed. The routine neurological examination was used to evaluate ISNAs that were clustered as central-based signs, cerebellar-based signs, and primitive reflexes. The items of Part-III of the Unified Parkinson's Disease Rating Scale were used to evaluate ISNAs that were clustered as mild parkinsonian signs. Associations of ISNAs with imaging findings were determined through logistic regression analysis. The ISNAs increase with the age and are present in all MCI types, particularly in those multiple domains, and carrying the APOE ϵ4 allele, and are associated with WMH, lacunes, BCr, and LVBr. This study demonstrates that cortical and subcortical vascular and atrophic processes contribute to ISNAs. Long prospective population-based studies are needed to disentangle the role of ISNAs in the conversion from MCI to dementia.

Mild Parkinsonian Signs in a Hospital-based Cohort of Mild Cognitive Impairment Types: A Cross-sectional Study.

Mild Parkinsonian Signs (MPS) have been associated with Mild Cognitive Impairment (MCI) types with conflicting results. To investigate the association of individual MPS with different MCI types using logistic ridge regression analysis, and to evaluate for each MCI type, the association of MPS with caudate atrophy, global cerebral atrophy, and the topographical location of White Matter Hyperintensities (WMH), and lacunes. A cross-sectional study was performed among 1,168 subjects with different types of MCI aged 45-97 (70,52 ± 9,41) years, who underwent brain MRI. WMH were assessed through two visual rating scales. The number and location of lacunes were also rated. Atrophy of the caudate nuclei and global cerebral atrophy were assessed through the bicaudate ratio, and the lateral ventricles to brain ratio, respectively. Apolipoprotein E (APOE) genotypes were also assessed. Using the items of the motor section of the Unified Parkinson's Disease Rating Scale, tremor, rigidity, bradykinesia, and gait/balance/axial dysfunction were evaluated. Bradykinesia, and gait/balance/axial dysfunction were the MPS more frequently encountered followed by rigidity, and tremor. MPS were present in both amnestic and non-amnestic MCI types, and were associated with WMH, lacunes, bicaudate ratio, and lateral ventricles to brain ratio. MPS are present in both amnestic and non-amnestic MCI types, particularly in those multiple domain, and carrying the APOE ε4 allele. Cortical and subcortical vascular and atrophic processes contribute to MPS. Long prospective studies are needed to disentangle the contribution of MPS to the conversion from MCI to dementia.

Image Guidance for Ventricular Shunt Surgery: An Analysis of Ventricular Size and Proximal Revision Rates.

Image guidance is a promising technology that could lead to lower rates of premature shunt failure by decreasing the rate of inaccurate proximal catheter placement. To perform a detailed radiographic analysis of ventricular size using 3 well-described methods and compare proximal revision rates. Our shunt surgery research database was queried to identify procedures (new placement or revision) where frameless stereotactic electromagnetic neuronavigation was used (January 2010-June 2016). A randomly selected cohort of surgeries done without image guidance during the same time period served as the comparison group. A radiographic analysis utilizing the following indices was used to classify ventricular size: bifrontal, bicaudate, and frontal-occipital horn ratio. The primary outcome was shunt failure due specifically to proximal catheter malfunction at 90 and 180 days. A total of 108 stereotactic and 95 free-hand cases were identified. Overall, there was no difference in ventricular size between the 2 groups. Neuronavigation yielded improved accuracy rates (73% grade 1; P<.001). Although there was no statistically significant difference in proximal revision rates when all patients were analyzed, there was a clinically beneficial reduction in the 90- and 180-day failure rates across all radiographic indices in children with small-to-moderate ventricular sizes when using image guidance. Electromagnetic neuronavigation results in more accurate placement of catheters, but did not result in an overall reduction in proximal shunt failure at 90 and 180days after the index surgery. However, subgroup analysis suggests a clinically important benefit in those patients with harder to cannulate ventricles.

Normal tension vs high tension glaucoma: an - overview.

The study provides an up-to-date overview of pathogenesis, functional and structural changes in normal tension glaucoma (NTG) and its differences from high tension glaucomas (HTG). The authors point to less known facts which make both diagnostic groups different. First of all, there are electrophysiological findings that verify pathology in the complete visual pathway in HTG in contrast to NTG where the retinal ganglion cell response is relatively normal but the abnormalities are in the visual pathway. This corresponds to the findings of functional magnetic resonance imaging of the brain with asignificant decrease in activity in HTG compared to NTG. We found ahigher decrease in activity in HTG following application of the colour paradigm compared to NTG where we did not see asimilar difference. We also investigated the central corneal thickness (CCT) in both diagnostic groups. We did not find astatistically significant difference. However, we found the effect of CCT on progression of the changes in visual fields in HTG. In relation to suspicion of abnormally low cerebrospinal pressure and apossible cerebrovascular fluid flow disturbance in NTG, we examined the optic nerve thickness (OND) and optic nerve sheath diameter (OSD) at adistance of 4, 8, 16 and 20mm from the posterior pole of the eye. In the comparison with the healthy population, we did not find any abnormalities except for the width of the optic chiasma that was markedly lower in NTG. In relation to apossible impairment of cerebral perfusion we determined the degrees of cerebral atrophy using magnetic resonance imaging by measuring the bicaudate ratio (BCR) and white matter lesions using the Fazekas scale. We did not find adifference between HTG and NTG in BCR. We found statistically significant changes in BCR which correlated with the changes in visual fields. The higher values of the pattern defect were associated with increased brain atrophy (BCR). We did not detect similar relations in the Fazekas scale. We found asignificant difference in this parameter among NTG, HTG and acontrol group. We found the most advanced changes in the patients with HTG. Conclusion: In HTG, impairment of retinal ganglion cells and subsequently also their axons, including visual cortex occurs because of ahigh intraocular pressure. In NTG, the retinal ganglion cells are relatively normal like the visual cortex, but alteration occurs in their axons. The cause is not ahigh intraocular pressure but most probably ischemia.

Nociceptive Primitive Reflexes in Neurologically and Cognitively Healthy Aging Subjects.

To assess the prevalence of three nociceptive primitive reflexes (nPR), i.e., glabellar tap, snout reflex, and palmomental reflex, in neurologically and cognitively healthy (NCH) aging subjects. To investigate whether nPR are cross-sectionally associated with white matter hyperintensities (WMH), lacunes, atrophy of the caudate nuclei, and global brain atrophy. A total of 1246 NCH subjects aged 45-91 years were included in the study and underwent standard brain MRI. Atrophy of the caudate nuclei and global brain atrophy were assessed through the bicaudate ratio (BCr) and lateral ventricles to brain ratio (LVBr), respectively. WMH were assessed through visual rating scales. Lacunes were also rated. Association of nPR with vascular risk factors/diseases and imaging findings was evaluated using logistic regression analysis. nPR were exhibited by 33.1% of subjects and increased with age. Subjects with nPR performed less than subjects without nPR in tests evaluating global cognition, executive functions, attention, and language. Snout reflex was the most common nPR, followed by glabellar tap and palmomental reflex. Glabellar tap was associated with parieto-temporal WMH, BCr, and LVBr; snout reflex was associated with frontal lacunes, temporal WMH, BCr, and LVBr; palmomental reflex was associated with parieto-occipital WMH, basal ganglia lacunes, BCr, and LVBr. This study demonstrates that in NCH aging individuals, nPR are associated with WMH, lacunes, BCr, and LVBr and are probably a warning sign of incipient cognitive decline. Therefore, NCH subjects presenting nPR should manage their vascular risk factors/vascular diseases rigorously in order to prevent or delay progression of small vessel disease, and future neurological and cognitive disabilities.

Abstract TP186: Impact of Long-term Left Ventricular Assist Device Support on Human Brain: A Case-control Study Using MRI

Introduction: Left ventricular assist device (LVAD) implantation improves the prognosis of patients with severe heart failure; however, the potential impact of long-term LVAD support on the brain remains unclear. The aim of this case-control study was to examine the characteristics of brain MRI in patients after long-term LVAD support. Methods: We retrospectively reviewed consecutive adult patients who underwent continuous-flow LVAD implantation in our hospital from 2010 to 2017, and those who underwent brain MRI after successful LVAD explantation were enrolled in this study. Age- and sex-matched control subjects (1:1) were selected from a pool of normal subjects who underwent MRI examination for screening purposes. The number and location of cerebral microbleeds (CMBs) and superficial siderosis, and the severity of white matter hyperintensity (WMH) and cerebral atrophy were compared between LVAD patients and controls. Results: We enrolled 49 LVAD patients and 49 controls. In LVAD patients, cardiomyopathy (84%) was the most common underlying heart disease. Heart transplantation was performed in 46 patients (94%) and 3 removed LVAD due to myocardial recovery. The median age was 41 years (range 19-66), and the median LVAD support time was 32 months (4-52). Nineteen patients developed symptomatic stroke (10 ischemic and 10 hemorrhagic) during LVAD support. Except for one, almost all (98%) LVAD patients had one or more CMBs, and the number of CMBs was much higher in the LVAD patients (mean, IQR: 7, 3-11 vs 0, 0-0: p&lt;0.001) than controls. Superficial siderosis was positive in 15 (31%) of LVAD patients, but not in controls. The severity of WMH was significantly higher both in deep subcortical (p=0.01), and periventricular region (p=0.04) than controls. In quantitative analyses of cerebral atrophy, bicaudate ratio (0.105±0.023 vs 0.089±0.019: p&lt;0.001) and cella-media index (0.160±0.033 vs 0.141±0.024: p&lt;0.001) were significantly higher in LVAD patients than controls. Conclusions: Patients after long-term LVAD support showed a high prevalence of CMBs and superficial siderosis, and more severe WMH and cerebral atrophy compared to age- and sex-matched controls. Long-term LVAD support may cause cerebral small vessel disease.