In normal aging ventricular system never attains pathological values of Evans' index

Frequency of brain ventricular enlargement among patients with diabetes mellitus

AIMS

To determine the prevalence of dilated ventricles and concomitant high blood glucose measures.

METHODS

We retrieved blood glucose measures from the emergency department database and selected a subgroup of individuals having both the radiological marker Evans' index (EI) values and blood glucose measures.

RESULTS

Out of 1221 consecutive patients submitted to axial Computed Tomography scans, a blood glucose measure was detected in 841 individuals. 176 scans (21 %) showed an EI > 0.30. According to the blood glucose categorization, diabetic patients were 104 (12 %), 25 of them (24 %) were dilated (mean EI 0.33). The age difference between dilated and not-dilated ventricles is about ten years in not-diabetic participants, whereas it is five years in diabetic participants. The age difference between dilated and not-dilated ventricles is about 10 years in diabetic men, whereas it zero in diabetic women.

CONCLUSIONS

Pathological ventricular enlargement is more frequent in men and in the elderly. In diabetic patients (especially women), the cerebral ventricles enlarge faster than in non-diabetic individuals. Age, sex, and diabetes may interact in determining how cerebral ventricle size changes over time, especially in diabetic women, making routine brain imaging advisable in these patients after the age of 70 years.

Prognostic Role of Ventricular Size and Its Dynamics in Patients With Leptomeningeal Metastasis From Solid Tumors

BACKGROUND AND OBJECTIVES

Hydrocephalus is a common radiologic sign in patients with leptomeningeal metastasis (LM) from solid tumors which can be assessed using the Evans index (EI). Here, we explored the prognostic value of ventricular size in LM.

METHODS

We identified patients with LM from solid tumors by chart review at 3 academic hospitals to explore the prognostic associations of the EI at diagnosis, first follow-up, and progression.

RESULTS

We included 113 patients. The median age was 58.3 years (interquartile range [IQR] 46.1-65.8), 41 patients (36%) were male, and 72 patients (64%) were female. The most frequent cancers were lung cancer (n = 39), breast cancer (n = 36), and melanoma (n = 23). The median EI at baseline was 0.28 (IQR 0.26-0.31); the EI value was 0.27 or more in 67 patients (59%) and 0.30 or more in 37 patients (33%). Among patients with MRI follow-up, the EI increased by 0.01 or more in 16 of 31 patients (52%), including 8 of 30 patients (30%) without and 10 of 17 patients (59%) with LM progression at first follow-up. At LM progression, an increase of EI of 0.01 or more was noted in 18 of 34 patients (53%). The median survival was 2.9 months (IQR 1-7.2). Patients with a baseline EI below 0.27 had a longer survival than those with an EI of 0.27 or more (5.3 months, IQR 2.4-10.8, vs 1.3 months, IQR 0.6-4.1) (HR 1.70, 95% CI 1.135-2.534, p = 0.0099). The median survival was 3.7 months (IQR 1.4-8.3) with an EI below 0.30 vs 1.8 months (IQR 0.8-4.1) with an EI of 0.30 or more (HR 1.40, 95% CI 0.935-1.243, p = 0.1113). Among patients with follow-up scans available, the overall survival was 9.4 months (IQR 5.6-21.0) for patients with stable or decreased EI at first follow-up as opposed to 5.6 months (IQR 2.5-10.5) for those with an increase in the EI (HR 1.08, 95% CI 0.937-1.243; p = 0.300).

DISCUSSION

The EI at baseline is prognostic in LM. An increase of EI during follow-up may be associated with inferior LM progression-free survival. Independent validation cohorts with larger sample size and evaluation of confounding factors will help to better define the clinical utility of EI assessments in LM.

Prevalence of idiopathic normal pressure hydrocephalus in patients with vertebral compression fractures

Background

Patients with idiopathic normal pressure hydrocephalus (iNPH) may be more prone to all fracture types due to falls. Vertebral compression fractures (VCFs) are a global burden that temporarily or permanently affects millions of elderly people. This study aimed to investigate the prevalence of iNPH in patients with VCFs.

Methods

We retrospectively reviewed 128 patients aged 60-102 years who underwent balloon kyphoplasty (BKP) for VCFs between November 1, 2017, and March 31, 2020. We also assessed the presence of the iNPH triad (i.e., gait disturbance, cognitive impairment, and urinary incontinence). Patients with Evans' index (EI) >0.3 and the iNPH triad were defined as having possible iNPH, those with clinical improvement after a cerebrospinal fluid tap test were defined as having probable iNPH, and those with clinical improvement after a shunt surgery were defined as having definite iNPH.

Results

Of the 128 patients, seven were excluded due to a history of intracranial disease that could cause ventricular enlargement or gait disturbance. Another 70 patients who did not undergo head computed tomography or magnetic resonance imaging one year before or after BKP were excluded from the study. Finally, 51 patients with a mean age of 78.9 years were enrolled. The mean EI value of these 51 patients was 0.28, with 18 patients showing EI >0.3. Moreover, 18 had possible iNPH, one had probable iNPH, and one had definite iNPH.

Conclusion

Screening for iNPH in elderly patients with VCFs can allow early diagnosis of iNPH and benefit them more from surgical treatment.

Predictors of Neurodevelopment in Microcephaly Associated with Congenital Zika Syndrome: A Prospective Study

The municipality of Salvador, situated in Brazil, distinguished itself as the epicenter of the emergence of microcephaly related to congenital manifestations of Zika syndrome. Despite the anticipated significant developmental setbacks in these children, research has indicated a varied range of outcomes, with certain instances even reflecting minimal developmental delay. Our objective was to pinpoint determinants that could forecast developmental anomalies in children diagnosed with microcephaly associated with congenital Zika syndrome (CZS).

METHODOLOGY

A forward-looking clinical and neurodevelopmental examination was conducted focusing on neonates diagnosed with microcephaly with CZS, birthed between September 2015 and April 2016 at the Hospital Geral Roberto Santos, in Salvador city. That infants were monitored up to their third year by a multiprofessional team. Child development was assessed using the composite Bayley III score. Undertaken by two blinded experts, cranial CT scan analysis was performed during the neonate period for the detection of brain abnormalities and to quantify ventricle enlargement, measured by Evans' index (EI).

RESULTS

Fifty newborns were evaluated with a median head circumference of 28 cm (interquartile range 27-31 cm). EI was associated with neurodevelopmental delay at three years and remained significant after adjustment for head circumference. A 0.1-point increase in EI was associated with a delay of 3.2 months in the receptive language (p = 0.016), 3.4 months in the expressive language (p = 0.016), 3.4 months in the cognitive (p = 0.016), 2.37 months in the gross motor (p = 0.026), and 3.1 months in the fine motor (p = 0.021) domains.

CONCLUSIONS

EI predicted neurodevelopmental delay in all Bayley domains in children with microcephaly associated with CZS.

Idiopathic normal pressure hydrocephalus possibly affects the occurrence of proximal femoral fracture

AIMS

The clinical triad of idiopathic normal pressure hydrocephalus (iNPH) includes gait disturbance, dementia, and urinary incontinence. These symptoms are also frequently observed in patients with proximal femoral fracture (PFF). The aim of this study was to investigate the relationship between PFF and iNPH retrospectively.

PATIENTS AND METHODS

Of the130 patients over 80-years-old with PFF included in this study, 48 were assigned to the PFF group. Forty-eight patients with peripheral vertigo matched with the PFF group for age and sex were included in the control group. We compared the Evans' index (EI), which is a head computed tomography finding of iNPH, and the percentages of patients with EI>0.3 between the two groups. The PFF group was further divided into two subgroups depending on whether EI was higher or lower than 0.3 (the higher or lower subgroup, respectively). We compared the patient's gait abilities before PFF, causes of PFF, cognitive functions, and occurrence of urinary incontinence between both groups.

RESULTS

The mean value of EI in the PFF group was significantly higher than that in the control group (PFF group, 0.301; control group, 0.284; p=0.008). The percentages of patients with EI>0.3 in the PFF and control groups were 62.5% and 35.4%, respectively (p=0.014). In subgroup analyses, the gait ability before injury was worse in the higher subgroup than that in the lower subgroup and was prominent among individuals who could walk only with human assistance (p=0.018). There were no significant differences in other parameters.

CONCLUSION

Elderly patients with PFF may have underlying idiopathic normal pressure hydrocephalus.

LEVEL OF EVIDENCE

III; case-control comparative study.

Imaging Markers for Normal Pressure Hydrocephalus: An Overview

Idiopathic bormal pressure hydrocephalus (iNPH) is a neurological syndrome that clinically presents with Hakim's triad, namely cognitive impairment, gait disturbances, and urinary incontinence. The fact that iNPH is potentially reversible makes its accurate and early diagnosis of paramount importance. Its main imaging characteristic is the dilation of the brain's ventricular system and the imaging parameters are also included in its diagnostic criteria along with clinical data. There is a variety of different modalities used and a great number of imaging markers that have been described while assessing iNPH patients. The present literature review attempts to describe the most important of these imaging markers and to shed some light on their role in diagnosis, differential diagnosis, and possibly prognosis of this potentially reversible neurological syndrome.

Examining for Cavum Septum Pellucidum and Ventricular Enlargement in Retired Elite-Level Rugby League Players

Objective

A cavum septum pellucidum (CSP) has been reported as a visible brain anomaly in normal individuals as well in some former combat and collision sport athletes. The appearance of CSP with fenestrations and ventricular enlargement are considered associated features of the neuropathological diagnosis of chronic traumatic encephalopathy. The current study examined CSP anatomic features and lateral ventricle size in retired elite rugby league players and controls.

Methods

Forty-one retired rugby league players and 41 healthy community controls, similar in age and education, underwent structural MRI scans. CSP grade, CSP length, corpus callosum septal length, and Evans' ratio (for lateral ventricle size) were rated by two of the current study authors. All participants also self-reported concussion exposure histories, depressive symptoms, daytime sleepiness, and impulsivity. They completed a neuropsychological test battery assessing premorbid intellectual functioning, attention, processing speed, language, visuospatial skills, memory, and aspects of executive functioning.

Results

The two raters had high agreement for CSP grade (Cohen's κ = 0.80), CSP length [intraclass correlation (ICC) = 0.99], corpus callosum septal length (ICC = 0.73), the CSP/septal ratio (ICC = 0.99), and the Evans' ratio (ICC = 0.75). Twenty-five retired players (61.0%) had an abnormal CSP compared to 17 controls [41.5%; χ(1, 82)2 = 3.12, p = 0.08, odds ratio = 2.21]. The CSP/septal ratio was larger for retired players than for the controls. The Evans' ratio did not differ between the two groups. In the retired rugby league players (n = 41), those with normal (n = 16) and abnormal (n = 25) CSP grades did not differ across age, age of first exposure to collision sport, years of sport exposure, concussion history, or 23 clinical and cognitive variables.

Conclusion

This study revealed a difference in the size of the CSP between retired professional rugby league players and controls. There was no significant difference in the size of the ventricles between the two groups. There were no significant differences between those with vs. without an abnormal CSP on age of first exposure to rugby league, years of exposure to repetitive neurotrauma, number of lifetime concussions, depression, impulsivity, perceived cognitive decline, or on any neuropsychological test.

Regional Brain Volume, Brain Reserve and MMSE Performance in Healthy Aging From the NEUROAGE Cohort: Contributions of Sex, Education, and Depression Symptoms

Objective: The aim of this study was twofold. First, to investigate the relationship between age, gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) volumes, brain reserve (BR), and specific regions of interest (ROIs) with global cognitive function in healthy older adults participating in a longitudinal study on aging in the island country of Cyprus. Second, to assess the contribution of important demographic and psychosocial factors on brain volume. Specifically, the effects of sex and years of education and the association between depression symptoms on brain volume were also explored in this Mediterranean cohort.

Methods: Eighty-seven healthy older adults (males = 37, females = 50) scoring ≥24 on the Mini-Mental State Examination (MMSE) were included, with a mean age of 72.75 years and a mean educational level of 10.48 years. The Geriatric Depression Scale was used to assess depression. T1-weighted magnetic resonance images were used to calculate global and regional volumes.

Results: Age was negatively correlated with GM, WM, BR, MMSE scores, and ROIs, including the hippocampus, amygdala, entorhinal cortex, prefrontal cortex, anterior cingulate gyrus, and positively with CSF. Higher MMSE scores positively correlated with GM volume. Women exhibited greater levels of depression than men. Depression was also negatively correlated with GM volume and MMSE scores. Men had greater ventricular size than women and participants with higher education had greater ventricular expansion than those with fewer years in education.

Conclusions: The reported structural changes provide evidence on the overlap between age-related brain changes and healthy cognitive aging and suggest that these age changes affect certain regions. Furthermore, sex, depressive symptomatology, and education are significant predictors of the aging brain. Brain reserve and higher education accommodate these changes and works against the development of clinical symptoms.

The association of disproportionately enlarged subarachnoid space hydrocephalus with cognitive deficit in a general population: the Ohasama study

Disproportionately enlarged subarachnoid space hydrocephalus (DESH) is the characteristic feature of idiopathic normal pressure hydrocephalus. We aimed to characterize the prevalence, development, and association of DESH to cognitive deficit in a large population. We reviewed the data of 1384 subjects eligible for the present study among 1590 participants who underwent magnetic resonance imaging (MRI) in the Ohasama Study, a population-based study in Ohasama, Japan. The participants with Mini-Mental State Examination (MMSE) score <  = 25 were assumed to have cognitive deficit and DESH was evaluated by reviewing the MRIs. We assessed the association between DESH, Evans index (EI), and cognitive deficit using multivariate logistic regression models adjusted for relevant confounders. Furthermore, we evaluated the new development of DESH and the deterioration of cognitive function in the participants with DESH. There were nine participants with DESH (0.65%), seven of whom showed cognitive deficit. DESH was significantly associated with cognitive deficit in multivariate regression analyses (odds ratio; 8.50 [95% confidence interval: 1.61–44.88]). In the 669 participants who underwent follow-up MRI, we found four participants newly presenting with DESH; the development of DESH was observed before/after the presence of EI > 0.3. We also found two participants with existing DESH showing no remarkable worsening in MMSE and EI. The present study demonstrated a positive association between the presence of DESH and cognitive deficit. DESH can develop independently of EI > 0.3, and ventricular enlargement in combination with DESH may be an important factor in the worsening of cognitive deficit.

Evans index among adult Ghanaians on normal head computerized tomography scan

Introduction

Normal-Pressure Hydrocephalus (NPH) is a neurological condition which is made up of a clinical triad of gait disturbance, dementia and urinary incontinence and can be reversed by ventricular shunting. Currently, some guidelines suggest the use of Evans' index (EI) for diagnosis of hydrocephalus radiologically. Most of the studies are based on the Western population data. None of these studies have been performed in the Ghanaian population setting yet. The aim of this study was to quantitatively establish normal borderline value for Evans Index in the Ghanaian adult population with respect to age and sex.

Methods

This study was retrospectively conducted on normal enhanced head CT scan images of 266 males and 241 females. EI was calculated as the linear ratio of Maximum Anterior Horn Width (MAHW) of the frontal horns of the lateral ventricles at the level of foramina of Monroe and the Maximum Intracranial Diameter (MICD) of the inner skull. Student T-test, ANOVA and Pearson's correlation were used to analyze the data. A test for a relationship was performed with a scatter plot and a linear regression was performed based on age, sex and different EI of ventricular size.

Results

The mean and median value of EI was 0.24 ± 0.02. There was no statistically significant difference in the EI values between males and females, (p-value = 0.61). A steady increase in EI with age was observed. There was a strong correlation coefficient r = 0.89 of EI and age, which suggested a strong linear relationship between EI and Age. The overall linear relationship model was EI = 0.1879 + 0.0011∗Age.

Conclusions

The mean EI of 0.24 ± 0.02 in our study agrees with adapted international guidelines cut-off value for normal adult patients of (<0.30) and can be a useful tool in determining ventricular enlargement particularly in resource limited settings.

Screening for idiopathic normal pressure hydrocephalus in the elderly after falls

OBJECTIVE

Many patients with idiopathic normal pressure hydrocephalus (iNPH) have reportedly fallen prior to diagnosis. However, there are no previous reports on the iNPH prevalence among the elderly with history of falls. This study investigated the effectiveness of screening for iNPH in elderly patients presenting after a fall.

METHODS

We retrospectively assessed the Evans' index (EI) of 235 consecutive patients aged 60-89 who presented after falls between May and October 2020. We also assessed the presence of the iNPH triad (gait disturbance, cognitive impairment, and urinary incontinence). Patients with EI > 0.3 and with all 3 triad were defined as having possible iNPH; those with clinical improvement after a cerebrospinal fluid (CSF) tap test as having probable iNPH; and those with clinical improvement after a shunt surgery as having definite iNPH. We also examined the 235 patients' EI, and performed a case-control study of EI using sex- and age-matched control patients.

RESULTS

Among the included 235 cases presenting after falls, 44 (18.7%) were diagnosed with possible iNPH, 29 (12.3%) with probable iNPH, and 25 (10.6%) with definite iNPH. The mean EI of these 235 patients was significantly larger than that of controls (0.30 ± 0.04 vs 0.26 ± 0.02, p < 0.0001). The proportion of possible iNPH in the cases was 44 out of 235 (18.7%), significantly higher than that of the controls (0%, p < 0.0001).

CONCLUSION

Screening for iNPH in the elderly presenting after falls can possibly identify iNPH patients in the earlier stage who may benefit more from surgical treatments.

Novel multi-linear quantitative brain volume formula for manual radiological evaluation of brain atrophy

Objectives

The brain atrophy commonly occurs in elderly and in some childhood conditions making the techniques for quantifying brain volume needful. Since the automated quantitative methods of brain volume assessment have limited availability in developing countries, it was the purpose of this study to design and test an alternative formula that is applicable to all healthcare levels.

Methods

The multi-linear diagonal brain fraction formula (DBF) was designed from dimensions of brain relative to skull and ventricles. To test a developed formula, a total of 347 subjects aged between 0 and 18 years who had brain CT scans performed recruited and subjected to a systematic measurement of their brains in a diagonal brain fashion.

Results

Out of 347 patients evaluated, 62 subjects (17.8 %) were found to be cases of brain atrophy. The three radiological measurements which included sulcal width (SW), ventricular width (VW) and Evans Index (EI) were concurrently performed. SW and VW showed good age correlation. Similar tests were extended to diagonal brain fraction (DBF) and skull vertical horizontal ratio (VHR) in which DBF showed significant age correlation.

Conclusions

The DBF formula shows significant ability of differentiating changes of brain volume suggesting that it can be utilized as an alternative brain fraction quantification method bearing technical simplicity in assessing gross brain volume.

Advances in knowledge

The designed formula is unique in that it captures even the possible asymmetrical volume loss of brain through diagonal lines. The proposed scores being in term of ratios give four grades of brain atrophy.

Natural history of ventriculomegaly in adults: a cluster analysis

OBJECTIVE

Chronic ventriculomegaly in the absence of raised intracranial pressure (ICP) is a known entity in adult hydrocephalus practice. The natural history and indication for treatment is, however, poorly defined. A highly heterogeneous group, some adults with ventriculomegaly are asymptomatic, while others have life-threatening deteriorations. The authors hypothesized that the various presentations can be subtyped and represent different stages of decompensation. A cluster analysis was performed on a cohort of patients with chronic ventriculomegaly with the aim of elucidating typical clinical characteristics and outcomes in chronic ventriculomegaly in adults.

METHODS

Data were collected from 79 patients with chronic ventriculomegaly referred to a single center, including demographics, presenting symptoms, and 24-hour ICP monitoring (ICPM). A statistical cluster analysis was performed to determine the presence of subgroups.

RESULTS

Four main subgroups and one highly dissimilar group were identified. Patients with ventriculomegaly commonly have a perinatal event followed by one of four main presentations: 1) incidental ventriculomegaly with or without headache; 2) highly symptomatic presentation (including reduced consciousness) and raised ICP; 3) early presenting with symptoms of headache and nausea (with abnormal pulsatility); and 4) late presenting with features common to normal pressure hydrocephalus. Each symptomatic group has characteristic radiological features, ICPM, and responses to treatment.

CONCLUSIONS

Cluster analysis has identified subgroups of adult patients with ventriculomegaly. Such groups may represent various degrees of decompensation. Surgical interventions may not be equally effective across the subgroups, presenting an avenue for further research. The identified subtypes provide further insight into the natural history of this lesser studied form of hydrocephalus.

The Ventricular System Enlarges Abnormally in the Seventies, Earlier in Men, and First in the Frontal Horn: A Study Based on More Than 3,000 Scans

Objectives: To detect on computed tomography (CT) brain scans the trajectories of normal and abnormal ventricular enlargement during aging.

Methods: For each 1-year age cohort, we assessed in 3,193 axial CT scans the Evans’ index (EI) in the anterior frontal horns and the parieto-occipital (POR) and temporal ratio (TR) in the posterior and inferior horns. Cut-off values for abnormal enlargement were based on previous clinical studies.

Results: The mean age associated with normal linear measures was 71 years. Values for all three measures increased with age, showing a linear relationship below—but not above—each cut-off value. The mean age of participants with abnormal enlargement on CT progressed from 79 years for EI to 83 years for POR to 87 years for TR. These results suggested that ventricular dilatation progresses in an age–location relationship. First comes enlargement of the frontal horns (13.8% of scans), followed by the parieto-occipital horns (15.1% of scans) and then temporal horn enlargement (6.8% of scans). Scans from men displayed abnormal values earlier than scans from women (on average 6 years). Risk increased 5.1% annually for abnormal EI, 9.0% for abnormal POR, and 11% for abnormal TR (all p < 0.001). The most frequent agreement between categories (normal–abnormal) for values of neuroimaging measures was identified for POR–TR.

Conclusion: The results of this large radiological study suggest that the ventricular system enlarges progressively during aging, and in a subset of patients follows an abnormal consecutive geometric dilatation, influenced by age and sex.

Delayed clearance of cerebrospinal fluid tracer from entorhinal cortex in idiopathic normal pressure hydrocephalus: A glymphatic magnetic resonance imaging study

The glymphatic system plays a key role for clearance of waste solutes from the rodent brain. We recently found evidence of glymphatic circulation in the human brain when using magnetic resonance imaging (MRI) contrast agent as cerebrospinal fluid (CSF) tracer in conjunction with multiple MRI acquisitions (gMRI). The present study explored the hypothesis that reduced glymphatic clearance in entorhinal cortex (ERC) may be instrumental in idiopathic normal pressure hydrocephalus (iNPH) dementia. gMRI acquisitions were obtained over a 24-48 h time span in cognitively affected iNPH patients and non-cognitively affected patients with suspected CSF leaks. The CSF tracer enrichment was determined as changes in normalized MRI T1 signal units. The study included 30 patients with iNPH and 8 individuals with suspected CSF leaks (i.e. reference individuals). Compared to reference individuals, iNPH patients presented with higher medial temporal lobe atrophy score and Evan's index and inferior ERC thickness. We found delayed clearance of the intrathecal CSF tracer gadobutrol from CSF, the ERC and adjacent white matter, suggesting impaired glymphatic circulation. Reduced clearance and accumulation of toxic waste product such as amyloid-β may be a mechanism behind dementia in iNPH. Glymphatic MRI (gMRI) may become a tool for assessment of early dementia.

Characterizing biomarker features of cognitively normal individuals with ventriculomegaly

INTRODUCTION

The clinical significance of ventriculomegaly in cognitively normal elderly individuals remains unclear.

METHODS

We selected cognitively normal individuals (n = 425) from the Alzheimer's Disease Neuroimaging Initiative database and calculated Evans index (EI) based on the ratio of the frontal horn and skull diameter. We defined ventriculomegaly as EI ≥ 0.30, and the participants were stratified into EI ≥ 0.30 group and EI < 0.30 group. Neuropsychological, imaging, and fluid biomarker profiles between the two groups were then compared using regression models.

RESULTS

A total of 96 (22.5%) individuals who had ventriculomegaly performed worse on the cognitive tests; showed smaller hippocampal volume but larger caudate, cingulate, and paracentral gyrus volumes; and displayed lower positron emission tomography [18F]fluorodeoxyglucose standardized uptake value ratio but higher amyloid burden represented by higher [18F]florbetapir standardized uptake value ratio and lower cerebrospinal fluid amyloid β 1-42 levels compared to those without ventriculomegaly.

DISCUSSION

Asymptomatic ventriculomegaly might be an early imaging signature of preclinical Alzheimer's disease and/or normal pressure hydrocephalus.

The Evans' Index revisited: New cut-off levels for use in radiological assessment of ventricular enlargement in the elderly

BACKGROUND AND PURPOSE

Assessment of ventricular enlargement is subjective and based on the radiologist's experience. Linear indices, such as the Evans Index (EI), have been proposed as markers of ventricular volume with an EI≥0.3 indicating pathologic ventricular enlargement in any subject. However, normal range for EI measured on magnetic resonance imaging (MRI) scans are lacking in healthy elderly according to age and sex. We propose new age and sex specific cut-off values for ventricular enlargement in the elderly population.

MATERIALS AND METHODS

534 participants (53% women) aged 65-84 years; 226 patients with Alzheimer's disease (AD), and 308 healthy elderly controls (CTR) from the AddNeuroMed and ADNI studies were included. The cut-off for pathological ventricular enlargement was estimated from healthy elderly categorized into age groups of 5 years range and defined as EI 97,5 percentile (mean+2SD). Cut-off values were tested on patients with Alzheimer's disease and a small sample of patients with probable idiopathic normal pressure hydrocephalus (iNPH) to assess the sensitivity.

RESULTS

The range of the EI in healthy elderly is wide and 29% of the CTR had an EI of 0.3 or greater. The EI increases with age in both CTR and AD, and the overall EI for women were lower than for men (p<0.001). New EI cut off values for male/female: 65-69 years 0.34/0.32, 70-74 years 0.36/0.33, 75-79 years 0.37/0.34 and 80-84 years 0.37/0.36. When applying the proposed cut-offs for EI in men and women aged 65-84, they differentiated between iNPH and CTR with a sensitivity of 80% and for different age and sex categories of AD and CTR with a sensitivity and specificity of 0-27% and 91-98%, respectively.

CONCLUSION

The range of the EI measurements in healthy elderly is wide, and a cut-off value of 0.3 cannot be used to differentiate between normal and enlarged ventricles in individual cases. The proposed EI thresholds from the present study show good sensitivity for the iNPH diagnosis.