NDVI-Based Lacunarity Texture for Improving Identification of Torreya Using Object-Oriented Method

Normalized Difference Vegetation Index （NDVI） is a very useful feature for differentiating vegetation and non-vegetation in remote sensed imagery. In the light of the function of NDVI and the spatial patterns of the vegetation landscapes, we proposed the lacunarity texture derived from NDVI to characterize the spatial patterns of vegetation landscapes concerning the ＂gappiness＂ or ＂emptiness＂ characteristics. The NDVI-based lacunarity texture was incorporated into object-oriented classification for improving the identification of vegetation categories, especially Torreya which was the targeted tree species in the present research. A three-level hierarchical network of image objects was defined and the proposed texture was integrated as potential sources of information in the rules base. A knowledge base of rules created by classifier C5.0 indicated that the texture could potentially be applied in object-oriented classification. It was found that the addition of such texture improved the identification of every vegetation category. The results demonstrated that the texture could characterize the spatial patterns of vegetation structures, which could be a promising approach for vegetation identification.

Spatial Structure Characteristics Detecting of Landform based on Improved 3D Lacunarity Model

The spatial structure characteristics of landform are the foundation of geomorphologic classification and recognition.This paper proposed a new method on quantifying spatial structure characteristics of terrain surface based on improved 3D Lacunarity model.Lacunarity curve and its numerical integration are used in this model to improve traditional classification result that different morphological types may share the close value of indexes based on global statistical analysis.Experiments at four test areas with different landform types show that improved 3D Lacunarity model can effectively distinguish different morphological types per texture analysis.Higher sensitivity in distinguishing the tiny differences of texture characteristics of terrain surface shows that the quantification method by 3D Lacu-narity model and its numerical integration presented in this paper could contribute to improving the accuracy of land-form classifications and relative studies.

Fractal lacunarity of trabecular bone and magnetic resonance imaging:New perspectives for osteoporotic fracture risk assessment

Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern even in aging men. Screening of the population at risk for bone degeneration and treatment assessment of osteoporotic patients to prevent bone fragility fractures represent useful tools to improve quality of life in the elderly and to lighten the related socio-economic impact. Bone mineral density(BMD) estimate by means of dual-energy X-ray absorptiometry is normally used in clinical practice for osteoporosis diagnosis. Nevertheless, BMD alone does not represent a good predictor of fracture risk. From a clinical point of view, bone microarchitecture seems to be an intriguing aspect to characterize bone alteration patterns in aging and pathology. The widening into clinical practice of medical imaging techniques and the impressive advances in information technologies together with enhanced capacity of power calculation have promoted proliferation of new methods to assess changes of trabecular bone architecture(TBA) during aging and osteoporosis. Magnetic resonance imaging(MRI) has recently arisen as a useful tool to measure bone structure in vivo. In particular, high-resolution MRI techniques have introduced new perspectives for TBA characterization by non-invasive non-ionizing methods. However, texture analysis methods have not found favor with clinicians as they produce quite a few parameters whose interpretation is difficult. The introduction in biomedical field of paradigms, such as theory of complexity, chaos, and fractals, suggests new approaches and provides innovative tools to develop computerized methods that, by producing a limited number of parameters sensitive to pathology onset and progression, would speed up their application into clinical practice. Complexity of living beings and fractality of several physio-anatomic structures suggest fractal analysis as a promising approach to quantify morphofunctional changes in both aging and pathology. In this particular context, fractal lacunarity seems to be the proper tool to characterize TBA texture as it is able to describe both discontinuity of bone network and sizes of bone marrow spaces, whose changes are an index of bone fracture risk. In this paper, an original method of MRI texture analysis, based on TBA fractal lacunarity is described and discussed in the light of new perspectives for early diagnosis of osteoporotic fractures.

Extraction of lacunarity variation index for revealing the slope pattern in the Loess Plateau of China

Lacunarity analysis is frequently used in multiscale and spatial pattern studies.However,the explanation for the lacunarity analysis results is limited mainly at a qualitative description level.In other words,this approach can be used to judge whether the spatial pattern of the objective is regular,random or aggregated in space.The lacunarity analysis,however,cannot afford many quantitative information.Therefore,this study proposed the lacunarity variation index(LVI)to reflect the rates of variation of lacunarity with the resolution.In comparison with lacunarity analysis,the simulated experiments show that the LVI analysis can distinguish the basic spatial pattern of the geography objects more clearly and detect the scale of aggregated data.The experiment showed that different slope types in the Loess Plateau display aggregated patterns,and the characteristic scales of these patterns were detected using the slope pattern in the Loess Plateau as the research data.This study can improve the spatial pattern analysis and scale detecting methods,as well as provide a new method for landscape and vegetation community pattern analyses.Lacunarity analysis is frequently used in multiscale and spatial pattern studies.However,the explanation for the lacunarity analysis results is limited mainly at a qualitative description level.In other words,this approach can be used to judge whether the spatial pattern of the objective is regular,random or aggregated in space.The lacunarity analysis,however,cannot afford many quantitative information.Therefore,this study proposed the lacunarity variation index(LVI)to reflect the rates of variation of lacunarity with the resolution.In comparison with lacunarity analysis,the simulated experiments show that the LVI analysis can distinguish the basic spatial pattern of the geography objects more clearly and detect the scale of aggregated data.The experiment showed that different slope types in the Loess Plateau display aggregated patterns,and the characteristic scales of these patterns were detected using the slope pattern in the Loess Plateau as the research data.This study can improve the spatial pattern analysis and scale detecting methods,as well as provide a new method for landscape and vegetation community pattern analyses.

Cognitive impairment in cerebral small vessel disease induced by hypertension

Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension and cerebral small vessel disease remains unclear.Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease.Chronic hypertension and lifestyle factors are associated with risks for stro ke and dementia,and cerebral small vessel disease can cause dementia and stroke.Hypertension is the main driver of cerebral small vessel disease,which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction,leukoaraiosis,white matter lesions,and intracerebral hemorrhage,ultimately res ulting in cognitive decline and demonstrating that the brain is the to rget organ of hypertension.This review updates our understanding of the pathogenesis of hypertensioninduced cerebral small vessel disease and the res ulting changes in brain structure and function and declines in cognitive ability.We also discuss drugs to treat cerebral small vessel disease and cognitive impairment.

Vitamin D deficiency and increased inflammatory factor intercellular cell adhesion molecule-1 indicate severe leukoaraiosis in northern China

Background and objective:Commonly plaguing in the frigid zone of the world,vitamin D deficiency,as indicated by low levels of 25-hydroxyvitamin D,exacerbated inflammatory responses and impaired endothelial function.Leukoaraiosis(LA)is a prevalent cause of cognitive dysfunction in the elderly and is potentially associated with inflammatory responses.This study aimed to investigate the impact of vitamin D on the severity of LA.Methods:Patients with LA were categorized based on 3.0 T brain MRI findings into mild(N=43),moderate(N=40),or severe groups(N=29)using the Fazekas scale(scoring 1-6).A control group consisting of 41 healthy individuals was included.Serum fibrinogen C,homocysteine,plasma 25-hydroxyvitamin D,and intercellular cell adhesion molecule-1(ICAM-1)levels were measured using ELISA.Results:All LA severity groups exhibited lower plasma 25-hydroxyvitamin D levels compared to the control group,with a more pronounced decrease observed as LA severity increased.Low plasma 25-hydroxyvitamin D was identified as an independent risk factor for LA(P<0.05)according to Multiple logistic regression analysis.Additionally,a negative association was observed between 25-hydroxyvitamin D and vascular inflammatory factor ICAM-1.Conclusions:Disease severity positively correlated with levels of the inflammatory marker ICAM-1,worsening as plasma 25-hydroxyvitamin D concentration decreased.Low 25-hydroxyvitamin D emerged as an independent risk factor for LA,potentially exacerbating the inflammatory response.These findings suggest 25-hydroxyvitamin D supplementation as a potential therapeutic approach for LA.

Fractal Measures of Drainage Network to Investigate Surface Deformation from Remote Sensing Data: A Paradigm from Hindukush (NE-Afghanistan)

This approach represents the relative susceptibility of the topography of the earth to active deformation by means of geometrical distinctiveness of the river networks. This investigation employs the fractal analysis of drainage system extracted from ASTER Global Digital Elevation Model (GDEM-30m resolution). The objective is to mark active structures and to pinpoint the areas robustly influenced by neotectonics. This approach was examined in the Hindukush, NE-Afghanistan. This region is frequently affected by deadly earthquakes and the modern fault activities and deformation are driven by the collision between the northward-moving Indian subcontinent and Eurasia. This attempt is based on the fact that drainage system is strained to linearize due to neotectonic deformation. Hence, the low fractal dimensions of the Kabul, Panjsher, Laghman, Andarab, Alingar and Kocha Rivers are credited to active tectonics. A comprehensive textural examination is conducted to probe the linearization, heterogeneity and connectivity of the drainage patterns. The aspects for these natural textures are computed by using the fractal dimension (FD), lacunarity (LA) and succolarity (SA) approach. All these methods are naturally interrelated, i.e. objects with similar FD can be further differentiated with LA and/or SA analysis. The maps of FD, LA and SA values are generated by using a sliding window of 50 arc seconds by 50 arc seconds (50" × 50"). Afterwards, the maps are interpreted in terms of regional susceptibility to neotectonics. This method is useful to pinpoint numerous zones where the drainage system is highly controlled by Hindukush active structures. In the North-Northeast of the Kabul block, we recognized active tectonic blocks. The region comprising, Kabul, Panjsher, Andrab, Alingar and Badakhshan is more susceptible to damaging events. This investigation concludes that the fractal analysis of the river networks is a bonus tool to localize areas vulnerable to deadly incidents influencing the Earth’s topography and consequently intimidate human lives.

Characterization of human retinal vessel arborisation in normal and amblyopic eyes using multifractal analysis

AIMTo characterize the human retinal vessel arborisation in normal and amblyopic eyes using multifractal geometry and lacunarity parameters.METHODSMultifractal analysis using a box counting algorithm was carried out for a set of 12 segmented and skeletonized human retinal images, corresponding to both normal (6 images) and amblyopia states of the retina (6 images).RESULTSIt was found that the microvascular geometry of the human retina network represents geometrical multifractals, characterized through subsets of regions having different scaling properties that are not evident in the fractal analysis. Multifractal analysis of the amblyopia images (segmented and skeletonized versions) show a higher average of the generalized dimensions (Dq) for q=0, 1, 2 indicating a higher degree of the tree-dimensional complexity associated with the human retinal microvasculature network whereas images of healthy subjects show a lower value of generalized dimensions indicating normal complexity of biostructure. On the other hand, the lacunarity analysis of the amblyopia images (segmented and skeletonized versions) show a lower average of the lacunarity parameter Λ than the corresponding values for normal images (segmented and skeletonized versions).CONCLUSIONThe multifractal and lacunarity analysis may be used as a non-invasive predictive complementary tool to distinguish amblyopic subjects from healthy subjects and hence this technique could be used for an early diagnosis of patients with amblyopia.

Structure Analysis and Classification of Precipitation Cells by Fractal Geometry

This paper analyzes the possibility to discriminate between convective precipitation and stratiform precipitation. This study aims to improve the measurement of rainfall from teledetection data obtained both on the ground and in space. For this, two parameters, fractal dimension and fractal lacunarity, are considered. To calculate the fractal dimension, we use the approach of box-counting and show that the fractal dimension differs between convectives cells and stratiforms ones. And then the fractal lacunarity parameter is calculated by using the sliding boxes algorithm. The study for all the regions shows that precipitation cells can be described by different lacunarities whatever the scale of analysis. We deduce that the two parameters, fractal dimension and fractal lacunarity, can be used to classify precipitations in convective regime and stratiform regime.

Structural Patterns of Immunoreactivity to Cytokeratin 18 in Normal Prostate and Benign Prostate Hyperplasia: Global and Local Differences

Background: Benign prostate hyperplasia (BPH) is the most common benign disease of the human prostate. The comparison between global versus local changes in spatial patterns of pathological lesions provoked a growing interest in some fields such as neuropathology. To date, there is little data on this subject in prostatic pathology. Given the interest of local parameters to distinguish between normal and pathological structures, the present study will apply first and second order stereological tools to find out if the cytokeratin18 (ck18) immunoexpression shows relevant local changes in BPH compared to normal prostate, independently if global estimates were similar in both groups. Methods: To verify if the global and local changes in immuno-expression of ck18 are relevant to ascertain differences between normal (CTR) and BPH cases, the following parameters will be applied: Volume fraction of epithelium immunostained for ck18 (VV ck18), both in global and local estimates;dispersion indices of VV ck18;estimates of local variance of VV ck18 (positional and of scale) using wavelet analysis;and lacunarity analysis to measure the tissue heterogeneity. Then, the set of values from the parameters studied that show significant differences between CTR and BPH will be employed to perform stepwise linear discriminant analyses to determine if locally estimated parameters were able to classify accurately the cases in CTR and BPH groups. Results and Conclusions: The findings of the present study indicate that changes in the expression of ck18 by the hyperplastic prostatic epithelium are not homogeneous. This limits the use of a single biopsy based markers to predict biological behavior in BPH. On the other hand, the local changes in the expression of ck18 are more evident in terms of VV ck18 and its local variability, whereas other parameters that are useful in other pathologies, such as lacunarity, are less relevant In prostatic hyperplasia.

Endothelial progenitor cells, potential biomarkers for diagnosis and prognosis of ischemic stroke: protocol for an observational case-control study

Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cells involved in both vasculogenesis and angiogenesis,may be a potential therapeutic target.After a stroke,EPCs migrate to the site of ischemic injury to repair cerebrovascular damage,and their numbers and functional capacity may determine patients'outcome.This study aims to determine whether the number of circulating EPCs and their functional aspects may be used as biomarkers to identify the type(cortical or lacunar)and/or severity of ischemic stroke.The study will also investigate if there are any differences in these characteristics between healthy volunteers over and under 65 years of age.100 stroke patients(50 lacunar and 50 cortical strokes)will be recruited in this prospective,observational case-controlled study.Blood samples will be taken from stroke patients at baseline(within 48 hours of stroke)and days 7,30 and90.EPCs will be counted with flow cytometry.The plasma levels of pro-and anti-angiogenic factors and inflammatory cytokines will also be determined.Outgrowth endothelial cells will be cultured to be used in tube formation,migration and proliferation functional assays.Primary outcome is disability or dependence on day 90 after stroke,assessed by the modified Rankin Scale.Secondary outcomes are changes in circulating EPC numbers and/or functional capacity between patient and healthy volunteers,between patient subgroups and between elderly and young healthy volunteers.Recruitment started in February 2017,167 participants have been recruited.Recruitment will end in November 2019.West Midlands-Coventry&Warwickshire Research Ethics Committee approved this study(REC number:16/WM/0304)on September8,2016.Protocol version:2.0.The Bayraktutan Dunhill Medical Trust EPC Study was registered in ClinicalTrials.gov(NCT02980354)on November 15,2016.This study will determine whether the number of EPCs can be used as a prognostic or diagnostic marker for ischemic strokes and is a step towards discovering if transplantation of EPCs may aid patient recovery.

Microbleeds in fronto-subcortical circuits are predictive of dementia conversion in patients with vascular cognitive impairment but no dementia

Cerebral small vessel disease（CSVD） is a common etiology of vascular cognitive impairment with no dementia（V-CIND）. Studies have revealed that cerebral microbleeds（CMBs）, a feature of CSVD, contribute to cognitive impairment. However, the association between CMBs and dementia conversion in individuals with V-CIND is still unclear. Here, we analyzed the predictive role of CMBs in the conversion from V-CIND to dementia in CSVD patients. We recruited and prospectively assessed 85 patients with CSVD and V-CIND. V-CIND was evaluated using a series of comprehensive neuropsychological scales, including the Chinese version of the Montreal Cognitive Assessment and the Clinical Dementia Rating. MRI assessments were used to quantify lacunar infarcts, white matter hyperintensities, CMBs, and medial temporal lobe atrophy. Eighty-two of the 85 patients completed the assessment for dementia conversion at a 1-year follow-up assessment. Multivariate logistic regression analyses were conducted to examine independent clinical and MRI variables associated with dementia conversion. Twenty-four patients（29.3%） had converted to dementia at the 1-year follow-up, and these individuals had significantly more CMBs in the fronto-subcortical circuits. Multivariate logistic regression analyses revealed that the patients with CMBs in the fronto-subcortical circuits（odds ratio = 4.4; 95% confidence interval： 1.602-12.081, P = 0.004） and 5 or more CMBs overall（odds ratio = 17.6, 95% confidence interval： 3.23-95.84, P = 0.001） had a significantly increased risk of dementia at the 1-year follow-up. These findings indicate that CMBs in the fronto-subcortical circuits may be predictive of dementia conversion in CSVD patients with V-CIND, and thus extend the clinical significance of CMBs.

Stroke and sleep-disordered breathing: A relationship under construction

The association between sleep-disordered breathing(SDB) and cardiovascular risk has been the focus of attention in recent years.Sleep disorders are emerging risk factors for cardiovascular disease and have been related to the whole spectrum of stroke,including transient ischemic attack,ischemic cerebral infarction and intracerebral haemorrhage.It has been shown that lacunar stroke or lacunar infarctions affecting the internal capsule or the protuberance are associated with a higher frequency of SDB.Acute stroke patients with associated SDB have a worse prognosis and a higher mortality as compared to patients with first-ever stroke without SDB.Preliminary studies provide evidence of the usefulness of treatment with continuous positive airway pressure when SDB is present in stroke patients.

Sodium ozagrel and atorvastatin for type 2 diabetes patients with lacunar cerebral infarction

BACKGROUND The main pathological factor of cerebral infarction is atherosclerosis,which is the pathological process of chronic inflammatory diseases such as vascular smooth muscle hyperplasia,inflammatory cell infiltration,extracellular matrix increase,and thrombosis.At present,the focus of clinical treatment is anti-platelet aggregation and improving blood status,and current research is limited to improving symptoms only.AIM To observe the effect of sodium ozagrel and atorvastatin on type 2 diabetes patients with lacunar cerebral infarction.METHODS Eighty-two patients with type 2 diabetes and lacunar cerebral infarction admitted to our hospital from January 2018 to February 2020 were equally categorized into two groups according to their treatment method.The control group was administered atorvastatin,and the observation group was administered sodium ozagrel combined with atorvastatin.The National Institutes of Health stroke scale(NIHSS)score,activities of daily living(ADL)score,blood glucose,lipid levels,inflammatory factors,high-mobility group box 1(HMGB1)levels,paraoxonase-1(PON-1)levels,erythrocyte sedimentation rate(ESR),and macrophage migration inhibitory factor(MIF)levels were recorded before and after treatment.The total effective rate and adverse reaction rate of the two groups were analyzed.RESULTS The total effective rate of the observation group(94.00%)was significantly higher than that of the control group(80.00%)(χ2=3.998;P=0.046).The blood glucose indexes,total cholesterol levels,triglyceride levels,low-density lipoprotein cholesterol levels,high-sensitivity C-reactive protein levels,interleukin-1βlevels,tumor necrosis factor-αlevels,HMGB1 Levels,ESR,MIF levels,platelet aggregation rates,and plasma viscosity of the two groups decreased after treatment;however,high-density lipoprotein cholesterol and PON-1 Levels increased after treatment.After treatment,the blood glucose indexes;blood lipid indexes;inflammatory factors;HMGB1,PON-1,and MIF levels;ESR;platelet aggregation rate;and plasma viscosity of the observation group were better than those of the control group(P<0.05).After treatment,all patients in the observation group had higher ADL scores and lower NIHSS scores than those in the control group(P<0.05).CONCLUSION Sodium ozagrel with atorvastatin can reduce inflammatory reactions;regulate ESR and HMGB1,PON-1,and MIF levels;control blood glucose and lipid indexes;and alleviate nerve injury without increasing adverse effects of atorvastatin alone.

Lacunar infarction with leukoaraiosis may aggravate cognitive dysfunction

This study semi-quantitatively analyzed the effects of leukoaraiosis.Patients with moderate or severe lacunar infarction were found to exhibit low scores on the Montreal Cognitive Assessment Scale （F=12.02,P=0.000）,and prolonged P300 Cz2.0 latency （F=16.04,P=0.000）.Correlation analysis revealed that the occurrence of leukoaraiosis was negatively correlated with Montreal Cognitive Assessment scores （r=-0.416,P=0.000）,and positively correlated with P300 Cz2.0 latency （r=0.538,P=0.000）.These findings indicate that leukoaraiosis aggravates cognitive impairment in patients with lacunar infarction,such that more severe leukoaraiosis is associated with more severe cognitive decline.

Association of ALOX5AP and PDE4D with the risk of lacunar infarct in people from Jiangsu Province,China

The genes for 5-1ipoxygenase activating protein （ALOX5AP） and phosphodiesterase 4D （PDE4D） have been demonstrated as susceptibility genes for lacunar in the Icelandic and Pakistani populations, but little is known about the role of these genes in Chinese populations. The present study utilized polymerase chain reaction and ligase detection reaction to detect single nucleotide polymorphisms （SNPs） in 280 consecutive stroke patients and 258 unrelated population-based controls from Nanjing, Jiangsu Province, China. The allele frequency, genotypes, and haplotypes of the two SNPs （rs456009 and rs966221） in PDE4D were similar between the two groups. However, A allele frequency of rs4073259 （A/G） and rs4769055 （A/C） in the ALOX5AP gene exhibited differences in two groups, and especially the haplotype of the SNP was significantly different between the two groups. Results suggested that the ALOX5AP gene might be involved in lacunar infarct, while PDE4D gene was not a risk factor for lacunar infarct in individuals from Jiangsu Province, China.

Correlative factors of cognitive impairment in patients with lacunar infarcts

Objective To study the relationships between cognitive impairment in patients with lacunar infarcts and quantitative CT measures and to determine the independent correlative factors of cognitive impairment.Methods Neuropsychological examination was conducted for 128 patients with acute lacunar infarct.Number,location,and volume of infarcts,cerebral atrophy index and severity of white matter lesions(WMLs) were measured and recorded.Results The number of lacunar infarcts in cognitive impairment (CI) group was significantly larger than that in cognitive normal(CN) group.Mean width of sulcus and sylvian fissure,index of frontal horn and ventricular-brain ratio(VBR) were significantly different in both groups.There were more patients with 3 grades or 4 grades WMLs in CI group(62%) than those in CN group(22%).The total volume of lacunar infarcts showed no statistically significant difference.Logistic regression analysis indicated that the number of lacunar infarcts in frontal subcortex and thalamus,the volume of infarcts in anterior periventricular white matter,width of cerebral sulcus and sylvian fissure were correlated with cognitive impairment respectively.Additionally,age and education were correlative factors of cognitive impairment in patients with lacunar infarct.Conclusion Correlative factors of cognitive impairment in patients with lacunar infarct are not merely one feature,but a combination of infarct features(number,location,and volume),cortical atrophy and host factors(age and education).

Correlation of ischemic ophthalmopathy with lacunar infarction

AIM:To investigate the correlation of ischemic ophthalmopathy(IO)with lacunar infarction(LI),an ischemic lesions in the cerebrovascular system.METHODS:Totally 204 cases of IO without any nervous system symptom and previously diagnosed LI served as the observational group.All 204 cases without IO,nervous system symptoms and previous LI served as the control group.Age and sex between the two groups matched well.LI was diagnosed by magnetic resonance imaging(MRI)and the results of the two groups were statistically analyzed and compared.RESULTS:IO included 174 eyes of 156 patients with non-arteritis anterior ischemic optic neuropathy(NAION),42 eyes of 36 patients with central retinal artery occlusion(CRAO)or branch retinal artery occlusion(BRAO)and 12 eyes of 12 patients with ocular ischemia syndrome(OIS).The detection rate of LI(72.54%)in IO group was obviously higher than that(15.68%)in the control group(P<0.001).IO was positively correlated with LI(r=0.573,P<0.05).In addition,most infarction sites located in the basal ganglia(67.57%),which were not the vital areas of cerebrum and not easy to be found due to their small size.The majority of those first visited IO patients(72.54%)without nervous system symptom and previously diagnosed LI had already suffered from LI.CONCLUSION:According to our studies,there is a positive correlation between IO and LI.IO can be used as an important predictor for the present of LI,especially obvious signs of the patient.

The relation between prognosis and nocturnal blood pressure variation in hypertensive patients with lacunar infarct

Objective We conducted a study using MRI and ambulatory blood pressure monitoring(ABPM) to determine whether an in-apporpriately low nocturnal blood pressure, or an excess fall in nocturnal blood pressure, might be responsible for lacunar infarct. Method ABPM and Casul blood pressure(CBP) were examined in 35 hypertentives with lacunar infarct(LI)and 33 hypertentives without lacunar infarct as control group. Results There is no significant difference of CBP between two groups. But the mean nighttime systolic blood pressure (nSBP) and diastolic blood pressure (nDBP) in patients with lacunar infarct were significantly smaller than in patients without lacunar infarct. The ratio of nSBP/dSBP and nDBP/dDBP in SI were smaller than in control group respectively. Conclusions The results indicate that an inap-propriately low nocturnal blood pressure, or an excessive fall in nocturnal blood pressure, is associated with lacunar infarct. It is necessary not only to control high blood pressure but also to pay attention to circadian changes of blood pressure during the course of anti-hypertensive treatment.

A case of paradoxical brain embolism presenting as a typical lacunar stroke

A 59 year old white male presented with a clinical picture typical of lacunar stroke. However, a thorough diagnostic work up showed that the most probable mechanism of stroke was paradoxical brain embolism through a patent foramen ovale. The clinical-neuroradiological mismatch that ultimately lead to the correct interpretation is discussed.