How to avoid false positive hyperdense middle cerebral artery sign detection in ischemic stroke

Objectives: The aim of the study was to find how to differentiate hyperdense middle cerebral artery sign (HMCAS) in stroke patients from asymmetric hyperdensity not related to stroke, by comparison of the CT density values typical for HMCAS to the values in normal or atherosclerotic middle cerebral artery (MCA). Methods: The group analyzed consisted of 100 patients with ischemic stroke, presenting HMCAS on the admission CT. Density measurements in HU were performed in the hyperdense segment of the involved MCA, contralateral MCA, brain cortex adjacent to the hyperdense MCA. The control group consisted of 100 patients with no symptoms of cerebral stroke. Density measurements in HU were performed: in the M1 segment of right and left MCA, brain cortex adjacent to the more dense from right or left MCA. Results: In the stroke group the median values obtained were: in the hyperdense MCA 59 HU, contralateral MCA 41 HU, brain cortex 36 HU. In the control group the median values obtained were: in the more dense MCA 43 HU, contralateral MCA 40 HU, brain cortex 34 HU. The range of HMCAS/contralateral MCA density ratios in stroke only slightly overlapped the range of more dense MCA/contralateral MCA density ratios in non-stroke patients. Conclusion: The ratio of hyperdense MCA CT density/contralateral density is a good tool to differentiate HMCAS from asymmetric hyperdensity not related to stroke. The threshold ≥1.16 provided 100% sensitivity and 97% specificity, whereas ≥1.22 provided 94% sensitivity and 100% specificity

Hyperdense middle cerebral artery sign as the only radiological manifestation of hyperacute ischemic stroke in computed tomography

Objectives: The main aim of the study was to find the effect of hyperdense middle cerebral artery sign (HMCAS), as the only admission computed tomography (CT) manifestation of ischemic stroke involving middle cerebral artery (MCA) region, on the extent of stroke measured by Alberta Stroke Program Early CT score (ASPECTS) in the follow-up CT. The secondary aim was to determine the correlation between length of hyperdense MCA segment on admission CT and ASPECTS in follow-up CT. Methods: The group analyzed consisted of 118 patients with ischemic MCA region stroke, with no early signs of brain tissue ischemia on admission CT, but infarcts confirmed in follow-up CT, with extent evaluated using ASPECTS. For the subgroups: 66 patients with HMCAS present and 52 with HMCAS absent, median ASPECTS values were compared. In the subgroup with HMCAS present, length of hyperdense segment was measured and correlation with ASPECTS was determined. Results: The median ASPECTS 6 (min. 0, max. 9) in the subgroup with HMCAS present was significantly lower, compared to the score 8.5 (min. 0, max. 9) in the subgroup with HMCAS absent. Moderate correlation between the length of hyperdense segment and ASPECTS was found (R = -0.45). Conclusion: In patients with ischemic stroke involving MCA region and no early signs of brain tissue ischemia on the admission CT, HMCAS is associated with significantly lower ASPECTS in the follow-up CT. There is moderate correlation between the length of hyperdense MCA segment and ASPECTS

The effect of software post-processing applications on identification of the penumbra and core within the ischaemic region in perfusion computed tomography

Purpose: Assessment of software applications designed for post-processing of CT imaging data and perfusion maps in terms of their ability to consistently define the penumbra and core in an ischemic area. Material and methods: This study is based on measurements conducted in a group of 65 patients with neurological symptoms suggestive of ischaemia in the area of the MCA within 12 hours following onset of the first symptoms. Non-contrast and perfusion CT were performed during an emergency duty. The acquired data were processed using various programs to obtain defined ischaemic areas and parameters. Finally, the results obtained were compared to the distribution of penumbra and core within the ischaemic area received from different perfusion mapping programs. Results: The programs designed to convert the acquired data and to map the distribution of perfusion were also assessed for their viability in dividing the ischaemic zone into penumbra and core. There was a statistically strong correlation (0.784-0.846) between results obtained by processing of imaging data with two different packages, and then by post-processing with one package, and a poor correlation (0.315-0.554) between results obtained by processing of data with the same package, and post-processing with two different packages designed for measuring penumbra and core areas. Conclusions: The results obtained by processing of imaging data with different software applications and by post-processing with one program developed for identifying penumbra and core areas show a strong correlation. However, the results obtained by processing imaging data with the same software application and by post-processing with different programs measuring penumbra and core areas reveal poor correlation

How to avoid false positive hyperdense middle cerebral artery sign detection in ischemic stroke

Objectives The aim of the study was to find how to differentiate hyperdense middle cerebral artery sign (HMCAS) in stroke patients from asymmetric hyperdensity not related to stroke, by comparison of the CT density values typical for HMCAS to the values in normal or atherosclerotic middle cerebral artery (MCA). Methods The group analyzed consisted of 100 patients with ischemic stroke, presenting HMCAS on the admission CT. Density measurements in HU were performed in the hyperdense segment of the involved MCA, contralateral MCA, brain cortex adjacent to the hyperdense MCA. The control group consisted of 100 patients with no symptoms of cerebral stroke. Density measurements in HU were performed: in the M1 segment of right and left MCA, brain cortex adjacent to the more dense from right or left MCA. Results In the stroke group the median values obtained were: in the hyperdense MCA 59 HU, contralateral MCA 41 HU, brain cortex 36 HU. In the control group the median values obtained were: in the more dense MCA 43 HU, contralateral MCA 40 HU, brain cortex 34 HU. The range of HMCAS/contralateral MCA density ratios in stroke only slightly overlapped the range of more dense MCA/contralateral MCA density ratios in non-stroke patients. Conclusion The ratio of hyperdense MCA CT density/contralateral density is a good tool to differentiate HMCAS from asymmetric hyperdensity not related to stroke. The threshold ≥1.16 provided 100% sensitivity and 97% specificity, whereas ≥1.22 provided 94% sensitivity and 100% specificity

Hyperdense middle cerebral artery sign as the only radiological manifestation of hyperacute ischemic stroke in computed tomography

Objectives The main aim of the study was to find the effect of hyperdense middle cerebral artery sign (HMCAS), as the only admission computed tomography (CT) manifestation of ischemic stroke involving middle cerebral artery (MCA) region, on the extent of stroke measured by Alberta Stroke Program Early CT score (ASPECTS) in the follow-up CT. The secondary aim was to determine the correlation between length of hyperdense MCA segment on admission CT and ASPECTS in follow-up CT. Methods The group analyzed consisted of 118 patients with ischemic MCA region stroke, with no early signs of brain tissue ischemia on admission CT, but infarcts confirmed in follow-up CT, with extent evaluated using ASPECTS. For the subgroups: 66 patients with HMCAS present and 52 with HMCAS absent, median ASPECTS values were compared. In the subgroup with HMCAS present, length of hyperdense segment was measured and correlation with ASPECTS was determined. Results The median ASPECTS 6 (min. 0, max. 9) in the subgroup with HMCAS present was significantly lower, compared to the score 8.5 (min. 0, max. 9) in the subgroup with HMCAS absent. Moderate correlation between the length of hyperdense segment and ASPECTS was found (R=−0.45). Conclusion In patients with ischemic stroke involving MCA region and no early signs of brain tissue ischemia on the admission CT, HMCAS is associated with significantly lower ASPECTS in the follow-up CT. There is moderate correlation between the length of hyperdense MCA segment and ASPECTS

Computed tomography assessment of brain atrophy in centenarians

The aim of our study was to compare the degree of brain atrophy in centenarians and in seniors 70–99 years old. The study group consisted of 23 patients aged 100–106 years. The control group consisted of 90 patients, 30 in each age subgroup 90–99, 80–89, 70–79. In all the patients, the brain atrophy linear parameters were measured on computed tomography scans, in relation to both “subcortical atrophy”, evaluated as progressive widening of the ventricular system, and “cortical atrophy”, defined as widening of subarachnoid space. Secondary indices based on the parameters were calculated. Correlations between the above parameters/indices and age were tested. Significantly different values between the centenarians and the control group were found in the brain atrophy parameters: A, B, C, E, FI, ICR, ICL, SW, CFW, F/A ‘frontal horn index’, A/G ‘Evans index’, D/A ‘ventricular index’, H/E ‘cella media Schiersmann index’, A+B ‘Huckman number’. Correlations between parameter/index and age were found for: A, B, C, FI, ICR, ICL, SW, F/A ‘frontal horn index’, A/G ‘Evans index’, D/A ‘ventricular index’, H/E ‘cella media Schiersmann index’, A+B ‘Huckman number’. Brain atrophy associated with aging is a continuously advancing process, affecting centenarians even more than people before the “magic” threshold of 100 years.centenariansbrain atrophycomputed tomograph

Biostimulants and microorganisms boost the nutritional composition of buckwheat ("Fagopyrum esculentum" Moench) sprouts

This study investigated the influence of biological control agents and plant growth promoters on the chemical composition of the cultivars Panda and Kora buckwheat sprouts. Before sowing, seeds were soaked in solutions containing Bacillus subtilis bacteria, Pythium oligandrum oospores, Ecklonia maxima algae extract, and/or nitrophenols. The sprouts of the Panda displayed higher levels of protein, fat, and dietary fiber fractions than the Kora. Measurable effects of biological control agents (BCAs) and plant growth promoters (PGPs) on the chemical composition of sprouts were also confirmed. Soaking the seeds in a solution containing P. oligandrum oospores resulted in a decrease in the level of crude ash in sprouts, while the addition of nitrophenols increased the level of both crude ash and protein. We also found statistically significant effects of interactions between the cultivar and BCA and/or PGP for each of the examined components

Microorganisms and Biostimulants Impacton the Antioxidant Activity of Buckwheat (Fagopyrum esculentum Moench) Sprouts

The study analyzes the influence of plant growth promoters and biological control agents on the chemical composition and antioxidant activity (AA) in the sprouts of buckwheat. The AA of cv. Kora sprouts was higher than cv. Panda, with 110.0 µM Fe2+/g (FRAP—Ferric Reducing Antioxidant Power), 52.94 µM TRX (Trolox)/g (DPPH—1,1-diphenyl-2-picrylhydrazyl), 182.7 µM AAE (Ascorbic Acid Equivalent)/g (Photochemiluminescence—PCL—ACW—Water-Soluble Antioxidant Capacity) and 1.250 µM TRX/g (PCL—ACL—Lipid-Soluble Antioxidant Capacity). The highest AA was found in the sprouts grown from seeds soaked in Ecklonia maxima extract and Pythium oligandrum (121.31 µM Fe2+/g (FRAP), 56.33 µM TRX/g (DPPH), 195.6 µM AAE/g (PCL—ACW) and 1.568 µM TRX/g (PCL—ACL). These values show that the antioxidant potential of buckwheat sprouts is essentially due to the predominant hydrophilic fraction of antioxidants. The AA of the sprouts was strongly correlated with total polyphenol content

The Effect of Bioaugmentation with Archaea on the Oxygen Uptake Rate in a Sequencing Batch Reactor

The aim of this study was to evaluate the effect of bioaugmentation with Archaea domain organisms on the activated sludge (AS) expressed by the oxygen uptake rate (OUR) in a laboratory sequencing batch reactor (SBR). The influence of depletion of the external substrate in bioaugmented (SBR-A) and non-bioaugmented (SBR-B) activated sludge during aerobic stabilization was investigated. The experiment was divided into two steps. First, the OUR was measured in the standard conditions of biological treatment. Second, AS was only aerated in the absence of the substrate. It was observed that bioaugmentation with Archaea had an increasing effect on the endogenous and exogenous OUR of the sludge in both phases. In the first phase, the average endogenous OUR was 28.70 ± 2.75 and 21.63 ± 0.9 mgO2·dm−3·h−1 in the SBR-A and SBR-B, respectively. Regarding the exogenous OUR, the average values were 95.55 ± 11.33 and 57.15 ± 24.56 mgO2·dm−3·h−1 for the SBR-A and SBR-B, respectively. Archaea enhancing its biological activity, expressed as the OUR, exert a stabilizing effect on this parameter of AS and ensure its lower sensitivity to changes in the process conditions, substrate supply disruption and prolonged aeration