Subcortical Vascular Encephalopathy Research Articles

Genomic analysis identify a new EIF2B3 gene variant detected in an uncertain case of CADASIL disease

Vanishing white matter disease (VWM) is an autosomal recessive leukodystrophy caused by mutations genes encoding the translational initiation factor 2B: EIF2B1-EIFB5. It is a heterogeneous neurological disorder with prominent cerebellar ataxia and spasticity in childhood-onset form and behavioural changes, dementia and seizures in adult-onset form (̴15% of cases). We present the case of a 60 years old patient, MTHFR homozygous, presenting white matter lesions and a subcortical vascular encephalopathy being diagnosed.

What are the Main Pathogenetic Features of Vascular Cognitive Impairment?

The term vascular cognitive impairment designates a heterogenous group of disorders ranging from mild cognitive impairment to full-blown dementia - vascular dementia - resulting from cerebrovascular lesions involving various brain areas. Current clinical criteria show moderate sensitivity (50-56%) and variable specifi city (range 64-98%). The prevalence in autopsy series ranges from 0.03 to 58% (mean 8-15% in Western series, 22-35% in Japan). Major morphological types - multiinfarct and subcortical vascular encephalopathy, strategic infarct dementia, lacunar state, granular atrophy (rare), and ischemic encephalopathy-are caused by atherosclerosis of major cerebral arteries and small vessel disease, resulting from systemic, cardiac and local vascular disease or cerebral amyloid angiopathy.

Gait disorders in adults and the elderly : Aclinical guide.

SummaryHuman gait depends on a complex interplay of major parts of the nervous, musculoskeletal and cardiorespiratory systems. The individual gait pattern is influenced by age, personality, mood and sociocultural factors. The preferred walking speed in older adults is a sensitive marker of general health and survival. Safe walking requires intact cognition and executive control. Gait disorders lead to a loss of personal freedom, falls and injuries and result in a marked reduction in the quality of life. Acute onset of a gait disorder may indicate a cerebrovascular or other acute lesion in the nervous system but also systemic diseases or adverse effects of medication, in particular polypharmacy including sedatives. The prevalence of gait disorders increases from 10 % in people aged 60–69 years to more than 60 % in community dwelling subjects aged over 80 years. Sensory ataxia due to polyneuropathy, parkinsonism and frontal gait disorders due to subcortical vascular encephalopathy or disorders associated with dementia are among the most common neurological causes. Hip and knee osteoarthritis are common non-neurological causes of gait disorders. With advancing age the proportion of patients with multiple causes or combinations of neurological and non-neurological gait disorders increases. Thorough clinical observation of gait, taking a focused patient history and physical, neurological and orthopedic examinations are basic steps in the categorization of gait disorders and serve as a guide for ancillary investigations and therapeutic interventions. This clinically oriented review provides an overview on the phenotypic spectrum, work-up and treatment of gait disorders.

Patient with rapidly evolving neurological disease with neuropathological lesions of Creutzfeldt‐Jakob disease, Lewy body dementia, chronic subcortical vascular encephalopathy and meningothelial meningioma

We report a case of rapidly evolving neurological disease in a patient with neuropathological lesions of Creutzfeldt-Jakob disease (CJD), Lewy body dementia (LBD), chronic subcortical vascular encephalopathy and meningothelial meningioma. The coexistence of severe multiple pathologies in a single patient strengthens the need to perform accurate clinical differential diagnoses in rapidly progressive dementias.

Joseph Haydn's encephalopathy: new aspects.

With increasing age, Joseph Haydn complained of progressive forgetfulness preventing him from composing for about the last 8 years of his life. He spent his days more and more inactive and immobilized, suffering from a disabling gait disturbance. Still, most biographers consider diffuse atherosclerosis and congestive heart failure to be reasons for Haydn's medical condition and physical decline during the last years of his life. A more sophisticated and detailed inspection of documents and sources, however, leads to the diagnosis of subcortical vascular encephalopathy (SVE), caused by progressive cerebral small vessel disease. Important features of the disease are mood changes, urinary symptoms, and in particular a characteristic gait disturbance, while dementia is only mild and occurs later in the course. Haydn was severely disabled by the symptoms of SVE for several years and often reported difficulties in the completion of his last oratorio "Die Jahreszeiten" (The Seasons). Subsequently, the disease prevented him from composing another large oratorio, "Das jüngste Gericht" (The last judgement), which had been already drafted. Finally, the progress of SVE stopped his long career as a composer and conductor at the age of 73 years.

Vascular dementia: Different forms of vessel disorders contribute to the development of dementia in the elderly brain

The diagnosis of vascular dementia (VaD) describes a group of various vessel disorders with different types of vascular lesions that finally contribute to the development of dementia. Most common forms of VaD in the elderly brain are subcortical vascular encephalopathy, strategic infarct dementia, and the multi infarct encephalopathy. Hereditary forms of VaD are rare. Most common is the cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Sporadic forms of VaD are caused by degenerative vessel disorders such as atherosclerosis, small vessel disease (SVD) including small vessel arteriosclerosis, arteriolosclerosis, and lipohyalinosis, and cerebral amyloid angiopathy (CAA). Less frequently inflammatory vessel disorders and tumor-associated vessel lesions (e.g. angiocentric T-cell or angiotropic large cell lymphoma) can cause symptoms of dementia. Here, we review and discuss the impact of vessel disorders to distinct vascular brain tissue lesions and to the development of dementia in elderly individuals. The impact of coexisting neurodegenerative pathology in the elderly brain to VaD as well as the correlation between SVD and CAA expansion in the brain parenchyma with that of Alzheimer's disease (AD)-related pathology is highlighted. We conclude that “pure” VaD is rare and most frequently caused by infarctions. However, there is a significant contribution of vascular lesions and vessel pathology to the development of dementia that may go beyond tissue damage due to vascular lesions. Insufficient blood blow and alterations of the perivascular drainage mechanisms of the brain may also lead to a reduced protein clearance from extracellular space and subsequent increase of proteins in the brain parenchyma, such as the amyloid β-protein, and foster, thereby, the development of AD-related neurodegeneration. As such, it seems to be important for clinical practice to consider treatment of potentially coexisting AD pathology in cognitively impaired patients with vascular lesions.

Direct Diagnosis is Superior to Risk Factor Prediction Tools for Management of Vessel Wall Disease

Diseases of the arteries cause more morbidity and mortality than most other non-communicable diseases, including cancer. Atherosclerosis, the most prevalent vasculopathy, leads to myocardial infarction, stroke, or occlusions of peripheral arteries, but also causes slowly progressive disorders such as subcortical vascular encephalopathy or chronic kidney disease. A patient not presenting with a vascular event is typically assessed for atherosclerosis indirectly by cardiovascular risk factor prediction tools, rather than directly by imaging of the vessel wall for primary prevention (Goldstein et al., 2011). Only after a clinical event such as a stroke, the arteries are imaged by ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), digital subtraction angiography (DSA). We suggest that, in primary prevention, a diagnostic paradigm that includes vascular imaging studies yields greater clinical benefits than assessing risk factors alone. Such an approach would provide an opportunity for customized therapy. The Framingham study provided evidence supporting a causative role of risk factors, such as hypertension, diabetes, and altered blood lipid profiles, for vascular events (Dawber et al., 1951). Based on these results, management strategies for the control of these risk factors were developed (Dawber et al., 1951; Bitton and Gaziano, 2010). Risk monitoring tools currently available include the Framingham risk score (FRS) and the University of Minnesota 10 Point Risk Scoring System (Cohn et al., 2003). Imaging techniques, such as measuring intimal medium thickness (IMT) in carotid ultrasound, assessing coronary calcium content by CT, vessel volume measurements by MRI, and pulse wave velocity (PWV) index for monitoring arterial compliance are available to identify generalized (systemic) atherosclerosis and can be used to follow the progression of the disease (Rao and Sriram, 2010). Recent studies utilizing CT and MRI have demonstrated that the FRS may fail to identify up to 30% of individuals with atherosclerotic vascular disease (Johnson and Dowe, 2010). One emerging technique to identify and track the progression (or regression) of carotid plaques is 3D ultrasound (Spence et al., 2002). Studies from the Robarts Research Institute in London, Ontario, have demonstrated that similar to total IMT measurements, total plaque volume (TPV), or total plaque area (TPA) measurements can be used to monitor the progression of atherosclerosis (Landry et al., 2004, 2005). Furthermore, these studies have demonstrated that aggressive lipid lowering using drugs such as atorvastatin can reduce the TPV significantly within 3 months. This technique has been shown to be sensitive enough to monitor diet or drug-induced changes in TPV. However, 3D ultrasound studies have also demonstrated that TPV may increase even after significant lowering of lipid levels, suggesting the need for additional therapies, such as antihypertensive therapy that has been shown to reduce plaque volume (Nissen et al., 2004). Although serial IMT measurement is more established, it is insensitive to drug-induced alterations in the TPV or TPA. Further studies of characterization of the morphology and composition of the plaque may enhance risk prediction. For decades, the FRS has been considered the gold standard for cardiovascular risk prediction. Cohn et al. (2003) demonstrated that the University of Minnesota 10 Point Scale, which combines laboratory and physiologic measurements, is superior to the FRS at predicting clinical events over a 6-year follow-up. However, newer techniques such as IMT and cardiac calcium scoring may replace indirect risk scoring systems. Recent 3D ultrasound techniques can monitor plaque volume, plaque progression, and plaque regression (Fenster et al., 2004, 2006; Landry et al., 2004, 2005, 2007; Ainsworth et al., 2005). Further studies on the morphology and composition of plaques will provide the ability to predict the nature of the plaque such as stability or vulnerability. There is an urgent need for the development of high-resolution, super-sensitive ultrasound systems that can monitor the atherosclerotic plaque in regional vascular beds of both small- and medium-sized vessels, so that the progression of the disease as well as the effectiveness of management of the disease with appropriate treatment modalities can be followed. We believe that the use of modern imaging techniques – especially of predilection sites of atherosclerosis, i.e., the carotids and the coronaries – as screening and monitoring tools in the primary prevention of vascular disease in addition to risk factor prediction could form the basis for a paradigm shift in vascular medicine from diagnosing risk factors to identifying the individual disease burden (see Table ​Table1).1). However, such new techniques need to show their predictive value for vascular events and progression of chronic vascular disease before they can be uniformly recommended. Table 1 Risk factors for modeling versus disease identification strategy.

Higher level gait disorders in subcortical chronic vascular encephalopathy: a single photon emission computed tomography study

the so-called higher level gait disorders include several types of gait disorders in which there are no major modifications in strength, tone, sensitivity, coordination and balance. Brain activation sites related to walking have been investigated using SPECT in humans. The aim of the study was to investigate brain activation during walking in subjects with high-level gait disorders due to chronic subcortical vascular encephalopathy. twelve patients with a chronic vascular encephalopathy were enrolled in the study. Seven subjects had apraxic gait while in the other five the gait was normal. All patients had undergone a recent cerebral magnetic resonance that revealed diffused chronic ischemic lesions within the white matter. all 12 patients underwent a regional cerebral blood flow (rCBF) brain SPECT study with (99m)Tc-Bicisate on two separate days and under two different conditions: at rest (baseline) and while walking (functional). the rCBF increase induced by the treadmill test (functional-baseline), bilaterally in the medial frontal gyrus and in the anterior lobes of the cerebellum, resulted significantly (P < 0.001) lower in patients with gait apraxia versus those without it. this study of the brain with SPECT records the areas of perfusion deficit that appear in apraxic subjects when they walk, compared with the recordings obtained with the same investigation performed at rest.

Striatal lesions in delusional parasitosis revealed by magnetic resonance imaging

Introduction Delusional parasitosis (DP) is a syndrome characterized by the firm conviction that small living beings infest the skin. The etiology can be primary and secondary. Structural brain abnormalities in DP have only been reported in case reports often subcortical vascular encephalopathy and right-hemisphere strokes in the temporo-parietal cortex. Systematic brain imaging studies are lacking. We aimed to identify a brain region with structural lesions in patients with DP in order to better understand the pathophysiology of DP. Methods Nine consecutive patients with DP in a psychiatric outpatient department were assessed clinically and by means of cranial magnetic resonance imaging (MRI). Results Five of the nine cases were diagnosed as having DP as psychotic disorders due to a general medical condition while three had DP arising from pre-existing psychiatric illness and one suffered from a delusional disorder, somatic type (primary form). Four of the five DP cases secondary to a general medical condition (one case could not be analyzed) had striatal lesions predominantly in the putamen. Thalamic or cortical lesions were found in one case, respectively. In the primary DP case and all cases secondary to another psychiatric disorder basal ganglia and subcortical gray matter lesions were absent. In all medical (secondary) DP cases subcortical white matter lesions were found mainly in the centrum semiovale. Three of the five medical DP cases showed severe generalized brain atrophy which was absent in the primary DP case and in the cases secondary to other psychiatric disorders. Discussion/conclusion We present the findings of the first structural MRI study in DP. Our results suggest a possible relevance of structural lesions in the striatum, predominantly the putamen, in the medical (secondary) DP-subgroup. Our findings are in line with other studies demonstrating that the putamen, in addition to its role in motor regulation, represents a brain area that mediates visuo-tactile perception. Disturbed functioning of the putamen and associated brain areas of the somatic/dorsal striato–thalamo–cortical loop might therefore play an important role in the pathophysiology of DP, which is characterized by somatic delusions, tactile misperceptions and sometimes also visual hallucinations. The involvement of the striatum and the efficacy of antidopaminergic antipsychotics indicate dopaminergic dysfunction in DP. Evidence from DP in intoxication with substances influencing the dopamine transporter (DAT) (e.g. cocaine, methylphenidate, bupropion) further supports this observation. Further neuroimaging studies in larger samples are needed to expand our preliminary knowledge obtained from this case-series study.

Differential pattern of hand‐tapping compromise in vascular versus idiopathic parkinsonism: A study based on computerized movement analysis

We tested the characteristics and the differential pattern of upper extremity motor compromise, comparing hand tapping in patients with subcortical vascular encephalopathy (SVE; n = 18), idiopathic Parkinson's disease (PD; n = 18), and in healthy controls (n = 18). Both patient groups showed significant compromise in hand tapping compared with that in controls, with higher coefficients of variability (CV) regarding tapping amplitude and angular velocity, determined using a computerized movement analysis system. A differential tapping pattern in both patient groups could be demonstrated in that patients with PD showed lower tapping amplitudes than patients with SVE. Both patient groups displayed abnormalities in tapping rhythmicity compared with that in the control group.

From trepidant abasia to motor network failure—gait disorders as a consequence of subcortical vascular encephalopathy (SVE): Review of historical and contemporary concepts

Gait disorders in progressive subcortical vascular encephalopathy (SVE) and their impact on the burden of disability in the growing elderly population are underrepresented in medical scientific literature. The absence of a clear framework for the diagnosis and classification for gait disorders on the basis of SVE has multiple reasons: (1) neither movement disorder specialists nor stroke specialists are truly familiar with this topic and feel responsible for its treatment, (2) the existing terminology lacks a clear concept and a consistent classification, and (3) only in recent years have large prospective trials started to address the natural course of SVE. This article reviews the classical descriptions of gait disturbances with preferential view to our present concept of SVE, and comments on historical and current nosology of gait disorders aiming to propose for a new classification.

Dementia in idiopathic Parkinson?s syndrome

Approximately 25% of patients with idiopathic Parkinson's disease (IPD) later develop dementia, with the typical characteristics as detailed in ICD-10 and DSM-IV. Differential diagnosis has to exclude dementia due to Lewy bodies, subcortical vascular encephalopathy and subcortical dementia due to progressive supranuclear paralysis or corticobasal degeneration. Several studies showed promising results for cholinesterase inhibitors such as donepezile, rivastigmine and galantamine. The demented Parkinsonian patients then present with improvement in cognitive function while motor skills do not deteriorate.

Amantadine Increases Gait Steadiness in Frontal Gait Disorder due to Subcortical Vascular Encephalopathy: A Double-Blind Randomized Placebo-Controlled Trial Based on Quantitative Gait Analysis

In a randomized, double-blind placebo-controlled trial, 40 patients diagnosed as subcortical vascular encephalopathy (SVE) were given a daily dose of 500 ml i.v. amantadine vs. placebo for 5 days. Both groups were treated with physiotherapy on a daily basis. Quantitative gait analyses were performed at days 1 and 6 to evaluate gait steadiness from cadence, length of heel-to-toe movements, variability of centre of gravity (COG) and double support time. Both placebo- and amantadine-receiving patient groups showed mild improvement in gait parameters after study, which failed to show the superiority of amantadine, when comparing drug-induced changes between both groups. However, analysing the treatment effects from day 0 to day 6 in both groups separately, statistically significant changes could be found in the amantadine group for cadence, length of heel-to-toe movements in single support phase as well as for variability in double support phase and double support time (two-tailed paired t-test, p < 0.05), whereas in the placebo group, a statistically significant effect could only be seen for double support time (p < 0.05). In this small pilot study, amantadine tends to improve gait steadiness as evaluated by cadence, length of heel-to-toe movements in single support phase, variability in double support phase and double support time, in patients with moderate frontal gait disorder due to SVE. Improvements in the placebo group can be interpreted as physiotherapy effect, which improved gait steadiness slightly, however, this was statistically significant only for double support time.

Elevated Levels of Fragmented DNA Nucleosomes in Native and Activated Lymphocytes Indicate an Enhanced Sensitivity to Apoptosis in Sporadic Alzheimer’s Disease

Apoptotic cell death is thought to be the most likely mechanism of cell death contributing to neurodegeneration in Alzheimer’s disease (AD). Here, we provide evidence that in sporadic AD cases the vulnerability of peripheral cells to undergo apoptosis is increased compared to non-demented elderly controls and, very importantly, to patients with subcortical vascular encephalopathy (SVE) as another, but demented control group. Quiescent ‘native’ and ‘activated’ lymphocytes from AD patients that were predisposed to commit apoptotic cell death by priming the cells with interleukin-2, are shown to accumulate apoptosing cells to a significantly higher extent in spontaneous and in oxidative stress-induced in vitro apoptosis. Our results demonstrate robust differences in cell death sensitivity between AD and vascular dementia. In none of the conditions investigated, lymphocytes from SVE patients were significantly different from non-demented controls. The comparable findings of a higher extent of apoptotic features in neurons and in peripheral blood cells of AD patients are remarkable and may suggest a rather general modulation of apoptotic mechanisms by the disease, which even can be picked up at the level of peripheral lymphocytes under specific in vitro conditions.

Homocysteine in Cerebrovascular Disease: an Independent Risk Factor for Subcortical Vascular Encephalopathy

Hyperhomocysteinemia is a risk factor for obstructive large-vessel disease. Here, we studied plasma concentrations of homocysteine and vitamins in patients suffering from subcortical vascular encephalopathy (SVE), a cerebral small-vessel disease leading to dementia. These results were compared to the homocysteine and vitamin plasma concentrations from patients with cerebral large vessel disease and healthy control subjects. Plasma concentrations of homocysteine, vascular risk factors and vitamin status (B6, B12, folate) were determined in 82 patients with subcortical vascular encephalopathy, in 144 patients with cerebral large-vessel disease and in 102 control subjects. Patients with SVE, but not those with cerebral large-vessel disease, exhibited pathologically increased homocysteine concentrations in comparison with control subjects without cerebrovascular disease. Patients with SVE also showed lower vitamin B6 values in comparison to subjects without cerebrovascular disease. Logistic regression analysis showed that homocysteine is associated with the highest risk for SVE (odds ratio 5.7; CI 2.5-12.9) in comparison to other vascular risk factors such as hypertension, age and smoking. These observations indicate that hyperhomocysteinemia is a strong independent risk factor for SVE.

Assessment of gait in subcortical vascular encephalopathy by computerized analysis: a cross-sectional and longitudinal study.

In subcortical vascular encephalopathy (SVE) gait disturbance is a common and early clinical sign which might be used to monitor disease progression. In the absence of reliable scales and with regard to the equivocal results of highly complex gait imaging devices we assessed the natural course of SVE in a prospective study, using a new straight forward technique to quantify and compare sequential gait studies. We report the results of 300 computerized gait analyses in 119 patients with SVE and 63 age-matched controls. Thirty-nine SVE patients were re-evaluated to monitor the natural course of the disease and to study the correlation of gait disturbances with MRI changes and neuropsychological findings. The system consists of a set of shoes containing 16 load sensors and a measuring-unit reading each sensor at 20-ms intervals. By off-line analysis we graded each recording on a Gait Disorder Score (GDS) with six variables indicating gait steadiness: step frequency, length of gait lines (which represent the movement of the centre of gravity during heel to toe movement), length of single support lines, variability of single and of double support lines, and double support time. In cross-sectional analysis, patients with SVE showed cadence (steps/min) to be reduced at 87.3 +/- 19.5 (96.4 +/- 7.8 in controls, P < 0.05). Length of gait lines was significantly less: 0.70 +/- 0.13 vs. 0.80 +/- 0.05 in controls, with length of single support gait lines reduced at 0.42 +/- 0.14 in SVE (0.58 +/- 0.06 in controls, P < 0.05). Variability of both single support lines (5.69 +/- 1.90%; 4.24 +/- 1.07% in controls, P < 0.05) and double support lines was elevated (3.59 +/- 1.62% vs. 2.54 +/- 0.59%), while duration of double support phases was increased (0.19 +/- 0.10 s vs. 0.13 +/- 0.02 s in controls, P < 0.05). The progressive character of the disease was demonstrated by increasing GDS values in 39 SVE patients with a frontal gait disorder who were re-investigated after a mean interval of 26 months (5.4 +/- 4.5 vs. 8.4 +/- 5.5, P < 0.05). This study shows the value of a new and practicable gait analysis system for the evaluation of gait disorders and it quantifies the deterioration of gait in SVE patients.

SPECT and PET imaging of the dopaminergic system in Parkinson's disease.

This paper gives an overview of the clinical importance of SPECT and PET imaging of the dopaminergic system in the differential diagnosis and for the determination of the progression rate of Parkinson's disease (PD). D2 receptor imaging can help to differentiate multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) from PD. In patients treated with neuroleptics it is possible to determine the rate of striatal D2 receptor blockade using this technique. This occupancy rate parallels the occurrence of parkinsonian side effects. Its measurement helps in the selection of newer atypical neuroleptics, which can be used to treat drug-induced psychosis in PD because they do not aggravate parkinsonian symptoms. Imaging of dopaminergic neurons with [123I]beta-CIT SPECT or [18F]DOPA PET is a way to visualize and quantify the nigrostriatal dopaminergic lesion in PD. Findings correlate with clinical rating scales and demonstrate the feasibility of detecting the preclinical lesion in patients with hemiparkinson or familial PD. [123I]beta-CIT SPECT can easily distinguish patients with essential tremor and patients with "lower body parkinsonism" due to a subcortical vascular encephalopathy. MSA and PSP cannot be separated from PD with this method alone. Longitudinal studies with [123I]beta-CIT SPECT and [18F]DOPA PET can quantify the progression rate in PD. SPECT results from our own group show a low rate of progression in patients with a long duration of disease and a more marked progression rate in patients with shorter disease duration. In the former group regions in the striatum with higher beta-CIT binding at the time of the first SPECT scan decline faster than regions with lower binding. These findings suggest a curvilinear course of progression which starts at different time points in different striatal regions and which levels off after several years of disease duration. These findings are in line with data from PET studies and underline the importance of an early start of neuroprotective strategies. Preliminary data from PET and SPECT studies in early PD suggest that dopamine agonists might have a slight neuroprotective effect and might slow down the rate of progression of the disease.

Impaired Vasoreactivity of the Basilar Artery System in Patients with Brainstem Lacunar Infarcts

Background and Purpose: Diminished vasoreactivity (VR) has been evidenced in patients with hemispheric small vessel disease, however, there is no data regarding vertebrobasilar (VB) territory VR changes in patients with subcortical vascular encephalopathy located in the brainstem. Therefore, we compared the cerebral blood flow velocity (CBFV) responses of the VB system during different vasoregulatory challenges in healthy volunteers to those in patients with brainstem lacunar infarcts. Methods: In 20 patients with brainstem lacunar infarcts and in 10 healthy volunteers the VR of the VB system was measured by analyzing the CBFV changes during different stimulation paradigms (ventilation, tilting and acetazolamide tests). During transcranial Doppler registration the systemic blood pressure and the expiratory partial CO₂ pressure were monitored. Results: During hypercapnia the VR was significantly higher in the control group than in the patient group (10.1 ± 4.9 vs. 3.4 ± 5.0 cm/s/kPa, p = 0.0025). In a subgroup of patients with mean baseline CBFV <25 cm/s the VR was 1.5 ± 2.4 cm/ s/kPa, while patients with mean baseline CBFV >25 cm/s showed a significantly higher value (7.8 ± 6.9 cm/s/kPa). Furthermore, in patients with mean baseline CBFV <25 cm/s the pulsatility index was significantly higher than in patients with mean baseline CBFV >25 cm/s (1.11 ± 0.26 vs. 0.86 ± 0.19, p = 0.0325), reflecting significantly higher vascular resistance in the former group. Although CBFV measurements during tilting and acetazolamide tests tended to support these findings, they showed no significant differences between patients and controls. Conclusion: Patients with cerebral microangiopathy involving the brainstem showed impaired VR in the VB flow territory in association with baseline CBFV.

Homocysteine in cerebral macroangiography and microangiopathy

Vascular dementia is the second most frequent cause of dementia in the elderly after Alzheimer's disease. Subcortical vascular encephalopathy (SVE), a distinct type of vascular dementia, is characterised by stepwise progressive memory deficits and cognitive decline, typical gait disorders, and incontinence.1 Sclerosis of small cerebral arteries and arterioles is responsible for the diffuse periventricular white-matter abnormalities and the central lacunar lesions evidenced in computed or magnetic resonance tomography.

Assessment of T2- and T1-weighted MRI brain lesion load in patients with subcortical vascular encephalopathy.

Previous cross-sectional studies in patients with subcortical vascular encephalopathy (SVE) have shown little or no correlation between brain lesion load and clinical disability, which could be due to the low specificity of T2-weighted MRI. Recent studies have indicated that T1-weighted MRI may be more specific than T2-weighted MRI for severe tissue destruction. We studied 37 patients with a diagnosis of SVE and 11 normal controls with standardised T1- and T2-weighted MRI. All patients underwent detailed clinical assessment including a neuropsychological test battery and computerised gait analysis. Both the T2- and T1-weighted total MRI lesion loads different between patients and controls different, particularly T1. The ratio of T2-/T1-weighted lesion load was lower in controls than in patients. There was no overall correlation of T1- or T2-weighted lesion load with clinical disability, but group comparison of patients with severe and mild clinical deficits showed different lesion loads. We suggest that T1- and T2-weighted MRI lesion loads demonstrate relevant structural abnormality in patients with SVE.