Frequency of silent brain infarction in transient global amnesia

Background and purpose To determine the frequency and distribution pattern of acute DWI lesions outside the hippocampus in patients clinically presenting with Transient Global Amnesia (TGA). Methods Consecutive patients clinically presenting with TGA between January 2010 and January 2017 admitted to our hospital were retrospectively evaluated. All patients fulfilled diagnostic criteria of TGA. We analyzed imaging and clinical data of all patients undergoing MRI with high-resolution diffusion-weighted imaging within 72 h from symptom onset. Results A total of 126 cases were included into the study. Fifty-three percent (n = 71/126) presented with one or more acute lesions in hippocampal CA1-area. Additional acute DWI lesions in other cortical regions were found in 11% (n = 14/126). All patients with DWI lesions outside the hippocampus presented with neurological symptoms typical for TGA (without additional symptoms.) Conclusions In a relevant proportion of clinical TGA patients, MRI reveals acute ischemic cerebral lesions. Therefore, cerebral MRI should be performed in patients with TGA to identify a possible cardiac involvement and to detect stroke chameleons.

Relationship between Retinal Microvasculature, Cardiovascular Risk and Silent Brain Infarction in Hypertensive Patients

Objective: The aims of this study are to analyze the role of artery-vein ratio AVR assessment using VesselMap 2 software (Imedos Systems) and cardiovascular risk evaluation by means of REGICOR in the prediction of silent brain infarction (SBI) in middle-age hypertensive patients from the ISSYS study. Material and Methods: A cross-sectional study with 695 patients with hypertension aged 50 to 70 years who participated in the project Investigating Silent Strokes in HYpertensives: a Magnetic Resonance Imaging Study (ISSYS), was conducted in two Primary Care Centres of Barcelona. Participants agreed to a retinography and an MRI to detect silent brain infarction (SBI). The IMEDOS software was used for the semiautomatic caliber measurement of retinal arteries and veins, and the AVR was considered abnormal when <0.66. The REGICOR score was calculated for all patients. Results: Multivariate logistic regression analysis was used to evaluate the impact of AVR and REGICOR scores on SBI. The OR (odds ratio) for a high REGICOR score and an abnormal AVR were 3.16 and 4.45, respectively. When analysing the interaction of both factors, the OR of an abnormal AVR and moderate REGICOR score was 3.27, whereas with a high REGICOR score it reached 13.07. Conclusions: The measurement of AVR in patients with hypertension and with a high REGICOR score can contribute to the detection of silent brain infarction.

Endocan: A Novel Predictor of Endothelial Dysfunction in Silent Brain Infarction

Silent brain infarction (SBI) has been considered as a subclinical risk factor for symptomatic possible future stroke. We investigated the association between serum inflammatory markers and SBI. Patients (n = 54) diagnosed with SBI as the study group and 52 individuals as the control group were included in this study. Silent brain infarction is defined as a hyperintense lesion that was ≥3 mm in 1 dimension on fluid-attenuated inversion recovery T2-weighted magnetic resonance image, if the patient had normal neurological examination or had an abnormality that was not consistent with the brain lesion locations, after being evaluated by a neurologist. Serum endocan levels ( P = .036) and high-sensitivity C-reactive protein (hsCRP; P = .022) were significantly higher in patients with SBI than the controls. Pentraxin 3, erythrocyte sedimentation rate, white blood count, lymphocyte, monocyte, neutrophil, low-density lipoprotein, and triglyceride levels were not significantly different when comparing the groups with and without SBI. There was a significant correlation ( r = −0.196; P = .16) between hsCRP and endocan levels in the SBI group. Endocan, a novel biomarker of endothelial pathology, was significantly increased in patients with SBI and may be useful to predict the future risk of stroke.

The 3’-UTR Polymorphisms in the Thymidylate Synthase (TS) Gene Associated with The Risk of Ischemic Stroke and Silent Brain Infarction

Thymidylate synthase (TS) is a key gene involved in the repair of DNA damage and DNA synthesis that plays an important role in vascular development and recovery. In particular, TS gene polymorphisms play a major role in the progression of vascular disease and cancer metastasis. Therefore, the aim of this study was to investigate the association of three TS polymorphisms (1100T>C [rs699517], 1170A>G [rs2790], and 1494ins/del [rs151264360]) with ischemic stroke and silent brain infarction (SBI) in Koreans. A total of 1299 participants (507 stroke patients, 383 SBI patients, and 409 controls) were enrolled in the study. Genotyping of the three TS polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis. To examine the association between TS gene polymorphisms and the diseases, we performed statistical analyses, including multivariable logistic regression and Fisher’s exact tests. We found that TS 1100T>C and 1170A>G genotypes were strongly associated with ischemic stroke and SBI susceptibility. More specifically, the TS 1100T > C polymorphism was associated with the likelihood of ischemic stroke (TT vs. CC: AOR = 2.151, 95% CI = 1.275–3.628, P = 0.004) and SBI (TT vs. TC+CC: AOR = 1.443, 95 % CI = 1.009–2.063, P = 0.045). In contrast, the TS 1170A > G polymorphism exhibited lower correlation with the risk of stroke (AA vs. GG: AOR = 0.284, 95% CI = 0.151–0.537, P < 0.0001) and SBI (AA vs. GG: AOR = 0.070, 95% CI = 0.016–0.298, P = 0.0002). Furthermore, we confirmed that the TS 1100T > C polymorphism was synergistic with low folic acid levels (AOR = 6.749, P < 0.0001). Altogether, these results suggest that TS 1100T > C and 1170A > G polymorphisms are associated with the risk of ischemic stroke and SBI, and our study provides the first evidence that 3′-UTR variants in TS are potential biomarkers in ischemic stroke and SBI.:

Effect of Methylenetetrahydrofolate Reductase (MTHFR) gene mutations and oxidative stress in silent brain infarction

Ischemic infarctions occur under the influence of genetic and environmental factors. In our study, the role of ischemia-modified albumin and thiol balance, which are new markers in determining oxidative damage together with MTHFR gene mutations and homocysteine levels, in the development of SBI was investigated. White matter lesions in the magnetic resonance imaging (MRI) results of the patients were evaluated according to the Fazekas scale and divided into groups (Grade 0, 1, 2, and 3). Homocysteine, folate, B12, IMA, total thiol, and native thiol were measured by biochemical methods. The mutations in MTHFR genes were investigated by the RT-PCR method. According to our results, a significant difference was found between the groups in age, homocysteine, folate, IMA, total thiol, and native thiol parameters (p<0.05). When we compared the groups in terms of genotypes of the C677T gene, we found a significant difference in TT genotype between grades 0/3 and 1/3 (p<0.05). We determined that homocysteine and IMA levels increased and folate levels decreased in CC/TT and CT/TT genotypes in the C677T gene (p<0.05). Considering our results, the observation of homocysteine and IMA changes at the genotype level of the MTHFR C677T gene and between the groups, and the deterioration of thiol balance between the groups suggested that these markers can be used in the diagnosis of silent brain infarction.