Search Results (119)

Background: Vascular dysfunction is increasingly recognized as a shared contributor to both cognitive impairment and late-life depression (LLD). However, the combined diagnostic value of cerebral hemodynamics, neuroimaging markers, and neuropsychological outcomes remains underexplored. This study aimed to investigate the associations be-tween transcranial Doppler (TCD) ultrasound parameters, cognitive performance, and depressive symptoms in older adults with mild cognitive impairment (MCI) and LLD. Importantly, we evaluated the integrative value of TCD-derived indices alongside MRI-confirmed white matter lesions (WMLs) and standardized neurocognitive and affective assessments. Methods: In this cross-sectional study, 96 older adults were enrolled including 78 cognitively unimpaired individuals and 18 with MCI. All participants underwent structured clinical, neuropsychological, and imaging evaluations including the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Geriatric Depression Scale (GDS-15), MRI-based Fazekas scoring of WMLs, and TCD ultrasonography of the middle cerebral artery. Hemodynamic variables included mean blood flow velocity (MBFV), end-diastolic velocity (EDV), pulsatility index (PI), and resistive index (RI). Logistic regression and receiver operating characteristic (ROC) analyses were used to identify independent predictors of MCI. Results: Participants with MCI showed significantly lower MBFV and EDV, and higher PI and RI (p < 0.05 for all) compared with cognitively unimpaired participants. In multivariate analysis, lower MBFV (OR = 0.64, p = 0.02) and EDV (OR = 0.70, p = 0.03), and higher PI (OR = 3.2, p < 0.01) and RI (OR = 1.9, p < 0.01) remained independently associated with MCI. ROC analysis revealed excellent discriminative performance for RI (AUC = 0.919) and MBFV (AUC = 0.879). Furthermore, PI correlated positively with depressive symptom severity, while RI was inversely related to the GDS-15 scores. Conclusions: Our findings underscore the diagnostic utility of TCD-derived hemodynamic parameters—particularly RI and MBFV—in identifying early vascular contributions to cognitive and affective dysfunction in older adults. The integration of TCD with MRI-confirmed WML assessment and standardized cognitive/mood measures represents a novel and clinically practical multi-modal approach for neurovascular profiling in aging populations. Full article

Background: Patients with chronic kidney disease (CKD) have a substantially higher risk of developing cognitive impairment (CI) than the general population. Patients with CKD undergoing haemodialysis (HD) treatment also have an elevated risk of developing cerebrovascular and cardiovascular diseases. This study aims to investigate the relationship between the cognitive performance of haemodialysis patients and cerebral and carotid haemodynamic indices. Methods: This study was a non-interventional observational study; the sample consisted of 32 patients (age 65 ± 12 years) undergoing chronic HD treatment. The patients underwent neuropsychological and haemodynamic instrumental investigations, including Supra-Aortic Trunk Echodoppler (SAT) and Transcranial Doppler (TCD). Results: Patients were 17% deficient at Montreal Cognitive Assessment (MoCA), 45% deficient at Frontal Assessment Battery (FAB), 55% deficient at Trail-Making Test-A (TMT-A) and 65% deficient at TMT-B. The TCD investigation detected a decrease in flow (MFV) and an increase in Breath Hold Index (BHI) predominantly in the right cerebral arterial district. The SAT investigation revealed an altered IMT, plaques and the presence of severe carotid stenosis. A strong association between cerebral and carotid indices and cognitive scores was also observed. Correlation analyses reported statistically significant correlations between TMT-A and TMT-B and cerebral flow indices. Conclusions: Among haemodialysis patients, there is a high percentage of cognitive impairment associated and correlated with alterations in cerebral and carotid haemodynamics. Cerebral haemodynamics are a factor to be taken into consideration as a possible pathological mechanism underlying cognitive impairment in haemodialysis. Full article

Background: Intracranial pressure (ICP) monitoring is crucial in managing acute brain injury (ABI) to prevent secondary brain injury. While invasive techniques remain the gold standard, they can carry notable risks, such as infection and hemorrhage. Non-invasive techniques are increasingly used, but their inter-modality correlation and concordance have not been systematically evaluated. This study aimed to assess the correlation and concordance among four commonly used non-invasive neuromonitoring tools in patients with ABI undergoing invasive ICP monitoring. Methods: This was a secondary analysis of prospectively collected data from 100 adult patients admitted to the intensive care unit with traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), or intracerebral hemorrhage (ICH) who underwent invasive ICP monitoring. Simultaneous assessments using optic nerve sheath diameter (ONSD), transcranial Doppler-derived pulsatility index (PI), estimated ICP (eICP), and the neurological pupil index (NPi) were performed. Correlation between modalities was assessed using Spearman’s correlation coefficient (ρ), and concordance was evaluated with Cohen’s kappa coefficient (k). Results: We found weak correlations between ONSD and PI (ρ = 0.29), ONSD and NPi (ρ = −0.33), and PI and NPi (ρ = −0.33); moderate correlations between ONSD and eICP (ρ = 0.54) and PI and eICP (ρ = 0.48); and a strong inverse correlation between eICP and NPi (ρ = −0.71; all p < 0.05). Concordance was generally low, with the highest agreement between PI and eICP (k = 0.69). Most other tool pairings showed poor-to-fair concordance (k ≤ 0.30). Conclusions: Non-invasive neuromonitoring tools show variable correlation and limited agreement, suggesting they are not interchangeable. Each modality captures different aspects of cerebral physiology, supporting the use of a multimodal approach to improve accuracy in ICP estimation. Full article

Artificial intelligence (AI) is revolutionizing the field of medical imaging, offering unprecedented capabilities in data analysis, image interpretation, and decision support. Transcranial Doppler (TCD) and Transcranial Color-Coded Doppler (TCCD) are widely used, non-invasive modalities for evaluating cerebral hemodynamics in acute and chronic conditions. Yet, their reliance on operator expertise and subjective interpretation limits their full potential. AI, particularly machine learning and deep learning algorithms, has emerged as a transformative tool to address these challenges by automating image acquisition, optimizing signal quality, and enhancing diagnostic accuracy. Key applications reviewed include the automated identification of cerebrovascular abnormalities such as vasospasm and embolus detection in TCD, AI-guided workflow optimization, and real-time feedback in general ultrasound imaging. Despite promising advances, significant challenges remain, including data standardization, algorithm interpretability, and the integration of these tools into clinical practice. Developing robust, generalizable AI models and integrating multimodal imaging data promise to enhance diagnostic and prognostic capabilities in TCD and ultrasound. By bridging the gap between technological innovation and clinical utility, AI has the potential to reshape the landscape of neurovascular and diagnostic imaging, driving advancements in personalized medicine and improving patient outcomes. This review highlights the critical role of interdisciplinary collaboration in achieving these goals, exploring the current applications and future directions of AI in TCD and TCCD imaging. This review included 41 studies on the application of artificial intelligence (AI) in neurosonology in the diagnosis and monitoring of vascular and parenchymal brain pathologies. Machine learning, deep learning, and convolutional neural network algorithms have been effectively utilized in the analysis of TCD and TCCD data for several conditions. Conversely, the application of artificial intelligence techniques in transcranial sonography for the assessment of parenchymal brain disorders, such as dementia and space-occupying lesions, remains largely unexplored. Nonetheless, this area holds significant potential for future research and clinical innovation. Full article

Functional transcranial Doppler (fTCD) ultrasound can detect cerebral blood flow lateralization to the left/right hemisphere during different tasks. This study aims to test the effectiveness of neurofeedback in improving the individual capacity to lateralize blood flow with mental activity. Bilateral monitoring of blood velocity (CBV) in the middle cerebral arteries was performed in 14 subjects engaged in 15 min of training, followed by a 15 min test in each of four sessions. A ball, displayed on a screen, moved right or left, according to the current right/left difference in normalized CBVs, thus providing a visual neurofeedback of lateralization. The subjects were invited to control the left/right movement of the depicted ball by appropriately orienting their mental activity, freely exploring different strategies. These attempts were completely free and unsupervised during training, while during the test, the subjects were required to follow randomized left/right cues lasting 35 s. Performance was assessed using receiver operating characteristic (ROC) analysis. With training, responses to left and right cues diverged more rapidly and consistently. Accuracy improved significantly from 0.51 to 0.65, and the area under the ROC increased from 0.55 to 0.69. These results demonstrate the effectiveness of neurofeedback in improving lateralization capacity, with implications for the development of fTCD-based brain–computer interfaces. Full article

Neurovascular coupling (NVC) refers to the dynamic regulation of cerebral blood flow via neuronal activity, a mechanism crucial for maintaining normal brain function. This review elucidates the intricate physiological mechanisms underlying NVC, emphasizing the coordinated roles of neurons, glial cells, and vascular cells in mediating activity-induced changes in blood flow. We examine how NVC is impaired in neurological disorders such as Alzheimer’s disease and stroke, where the dysfunction of this coupling contributes to neurodegeneration and neurological deficits. A broad range of techniques for assessing NVC is discussed—encompassing the established modalities like transcranial Doppler, near-infrared spectroscopy, and functional magnetic resonance imaging (fMRI), as well as emerging technologies such as functional ultrasound imaging and miniaturized endoscopy that enable high-resolution monitoring in deep brain regions. We also highlight the computational modeling approaches for simulating NVC dynamics and identify the novel biomarkers of NVC dysfunction with potential utility in early diagnosis. Finally, emerging translational applications—including neuromodulation techniques and targeted pharmacological interventions—are explored as means to restore normal neurovascular function. These advancements underscore the clinical significance of NVC research, paving the way for improved diagnostic tools and therapeutic strategies in neurological disorders. Full article

Background: We observed a COVID-19 survivor with a ventriculoperitoneal shunt who developed increased intracranial pressure during hemodialysis. We hypothesized that post-SARS-CoV-2 infection, patients may have altered cerebral perfusion pressure regulation in response to intracranial pressure changes. Methods: From April to July 2021, we recruited dialysis patients with prior COVID-19 from two Madrid nephrology departments. We also recruited age- and sex-matched dialysis patients without prior SARS-CoV-2 infection. Transcranial Doppler ultrasound was used to measure the middle cerebral artery velocity before dialysis and 30, 60, and 90 min after the initiation of dialysis. Results: The final sample included 37 patients (16 post-COVID-19 and 21 without). The COVID-19 survivors showed a significant pulsatility index increase between 30 and 60 min compared to those without COVID-19. They also had lower heart rates. Conclusions: We propose two mechanisms: an increase in intracranial pressure or a decreased arterial elasticity. A lower heart rate was also observed in the COVID-19 survivors. This study highlights SARS-CoV-2’s multifaceted effects, including potential long-term vascular and cerebral repercussions. Full article

Background: Cerebral vasospasm after craniotomy tumor (CVACT) is a rare complication that can occur following tumor craniotomy and significantly affects the outcome of patients. Unfortunately, it is not well understood, leading to delayed and ineffective management. This study aims to investigate CVACT by examining the factors contributing to its occurrence, its underlying mechanisms, diagnostic approaches, management strategies, and outcomes. The goal is to identify the characteristics and risk factors associated with CVACT, its clinical symptoms, diagnostic methods, management options, and potential outcomes. Methods: A systematic search used relevant keywords to identify cases of “cerebral vasospasm” after tumor resection in PubMed and Science Direct databases. Relevant cross-references were added by manually searching the references of all retrieved articles. Result: We included 60 inclusion patients from 14 case reports and 13 case series with 33 (55%) females and 27 (45%) males with a mean age of 44.05 ± 16.8 years. The most common tumors were pituitary adenomas, which were found in 22 (36.66%), the most common tumor location was the middle cranial fossa (75%), and the most common surgery technique used was transsphenoidal surgery (50%). Most of those who experience vasospasm have a craniotomy with the TSS technique (50%) with complications of intraoperative bleeding. The range of onset of VS symptoms postoperatively was 0–30 days (mean 6.59 d). The symptoms included asymptomatic, headache, loss of vision, hemiparesis, diplopia, etc. The vascular involvement was mainly anterior circulation (78.33%). The diagnostic tools most commonly used were angiography and transcranial doppler (TCD). The most common management of VS from the included studies was pharmacology. The survival rate was 61.66%. We found the tumor location and vascular-affected vasospasm were significantly correlated with mortality rates: p = 0.015 and p = 0.02. Conclusions: Cerebral vasospasm after craniotomy tumor removal (CVACT) frequently arises in tumors situated in the medial cranial fossa, predominantly pituitary adenomas and meningiomas. The minimally invasive surgical approach of TSS may contribute to the mechanism of CVACT incidence. The existence of preoperative vascular pathology, as encasement or narrowing, appears to be a predictor alongside the incidence of intra- or postoperative hemorrhage. The vascular structures most susceptible to vasospasm are located in the anterior circulation of the Willis circle, which appears to correlate with the vascular problems that typically undergo preoperative encasement of the internal carotid artery (ICA). The most reliable and real time diagnostic instrument employed is TCD, while imaging continues to be the gold standard. Nimodipine treatment continues to be a viable therapeutic option that can enhance patient outcomes. Full article

The diagnosis of aneurysmal subarachnoid hemorrhage (aSAH) is most difficult in patients who are in good clinical condition with a small hemorrhage, especially when a ruptured aneurysm might not be considered, or if a computed tomographic (CT) scan is not obtained, or if when a CT is obtained, the findings are subtle and missed by an inexperienced reviewer. All acute onset (thunderclap) headaches should be considered ruptured aneurysms until proven otherwise. Treatment begins with immediate control of pain and blood pressure, placement of an external ventricular drain (EVD) in poor-grade patients and those with acute hydrocephalus on CT scanning, administration of antifibrinolytic tranexamic acid, and then repair of the aneurysm with either surgical clipping or endovascular techniques as soon as the appropriate treatment team can be assembled. After securing the aneurysm, aSAH patient treatment is focused on maintaining euvolemia and a favorable systemic metabolic state for brain repair. A significant and aneurysm-specific threat after aSAH is delayed arterial vasospasm and resulting cerebral ischemia, which is detected by vigilant bedside examinations for new-onset focal deficits or neurological decline, assisted with daily transcranial Doppler examinations and the judicious use of vascular imaging and cerebral perfusion studies with CT. The management of diagnosed symptomatic vasospasm is the prompt induction of hypertension with vasopressors, but if this fails to reverse deficits quickly after reaching a target systolic blood pressure of 200 mmHg, endovascular angioplasty is indicated, providing CT scanning rules out an established cerebral infarction. Balloon angioplasty should be considered early for all patients found to have severe angiographic vasospasm, with or without detectable signs of ischemic neurological deterioration due to either sedation or a pre-existing deficit. Full article

Background: Preeclampsia (PE) and eclampsia are characterized by changes in cerebral hemodynamics, which may result in serious and even life-threatening neurological complications. The aim of the present work was to compare cerebral hemodynamic changes during the roll-over test in women with mild and severe PE. Patients and methods: Healthy pregnant and PE women in their third trimester were studied. Transcranial Doppler (TCD) measurements of the right middle cerebral artery (MCA) were performed in the left lateral position and 5 min after turning to the supine position (roll-over test = ROT). Besides cerebral blood flow measurements, the blood pressure was measured in the right arm using a standard mercury sphygmomanometer. An independent gynecologist categorized the preeclamptic patients into mild and severe groups based on the clinical and laboratory results. The TCD assessors were unaware of the patient grouping while performing the TCD and blood pressure measurements. Results: A total of 21 healthy pregnant females (mean age: 26.1 ± 5.1 yrs), 11 females with mild PE (28.2 ± 6.8 yrs), and 18 females with severe PE (29 ± 7.4 yrs) were studied. A significant increase in the mean arterial pressure was observed in all of the groups during the roll-over test: healthy pregnant patients: from 106.3 ± 16.3 to 113.8 ± 15.9 mmHg; patients with mild PE: from 100 ± 11.2 to 110 ± 8.7 mmHg; and patients with severe PE: from 106.3 ± 16.3 to 113.8 ± 15.8 mmHg. The MCA mean blood flow velocities in the left lateral position were significantly lower in the control patients than in those with PE: MCAV control: 71.2 ± 12.7 cm/s; mild PE: 78.2 ± 19.4 cm/s; and severe PE: 96 ± 15.6 cm/s, p < 0.001. Turning to the supine position resulted in a decrease in the MCAV in all of the groups, but the differences between the groups remained unchanged: controls: 69.5 ± 9.1 cm/s; mild PE: 75.7 ± 17.5 cm/s; and severe PE: 85.7 ± 18.4 cm/s, respectively, p = 0.014. A slight but statistically insignificant increase in the pulsatility index was observed in all of the groups. Conclusions: This is the first study comparing cerebral hemodynamic changes in healthy pregnant females and in those with mild and severe PE during a roll-over test. Changing the posture did not result in changes in the cerebral blood flow velocities in the healthy and preeclamptic pregnant patients. Our results indicate that static cerebral autoregulation is preserved both in the mild and severe preeclamptic patients. Full article

Sepsis-associated encephalopathy (SAE) is linked to high mortality and impaired neurologic outcome. Brain ultrasonography (US) is a non-invasive tool for cerebral monitoring. A scoping review of the literature in three databases was performed to answer if brain perfusion is altered in sepsis, to determine the role of brain US in guiding resuscitation and its ability to predict the outcome. Randomized controlled trials, clinical trials, observational studies, and systematic reviews on adults with sepsis or septic shock in the ICU were included. A total of 625 articles were screened, and 34 included. There were 85% observational studies and 15% systematic reviews with or without meta-analysis. The majority of studies had a small sample size and used different metrics. The studies focused on cerebral blood flow (CBF) alterations reporting variable results (CBF increased, normal, or decreased). The findings showed a variable rate of cerebral autoregulation (CAR) impairment, with higher incidence in the early stages of sepsis and associations with poor neurological outcomes. However, the impact of CAR and CBF alterations on neurological outcomes and mortality was not clear. Very few studies were found on resuscitation. In conclusion, brain US can identify cerebral perfusions alterations and its usage in sepsis is promising. However, the current body of evidence for its usage is poor and lacks standardization. Full article

Background: Decreased cerebral oximetry (rSO₂) in cardiac surgery is associated with postoperative delirium (POD). However, interventions optimizing intraoperative rSO₂ are inconclusive. Methods: In this prospective observational cohort study, the relationship between rSO₂, middle cerebral artery blood flow velocity (MCAV), and processed EEG was assessed in cardiac surgery patients with and without POD. MCAV was continuously recorded by transcranial Doppler sonography (TCD), together with continuous rSO₂ and bispectral index (BIS) monitoring. Cardiopulmonary bypass (CPB) flow rate was adjusted according to body surface area. The cohort was divided into the POD and control groups, according to the postoperative results of the confusion assessment method (CAM/CAM-ICU), the 4A’s test (4AT), and the Delirium Observation Scale (DOS). A mixed model analysis was performed for intraoperative raw data. The cerebral autoregulation index was calculated from TCD, rSO₂, and arterial pressure values. Differences in impaired autoregulation were compared using the Mann–Whitney U test. Results: A total of 41 patients were included in this study. A total of 13 patients (36.11%) developed postoperative delirium. There were no significant differences in the baseline characteristics of patients with or without POD. Patients with POD had lower BIS values during CPB (adjusted mean difference −4.449 (95% CI [−7.978, −0.925])). RSO₂ was not significantly reduced in POD, (adjusted mean difference: −5.320, 95% CI [−11.508, 0.874]). In contrast, MCAV was significantly increased in POD (10.655, 95% CI [0.491, 20.819]). The duration of cerebral autoregulation impairment did not differ significantly for TCD and cerebral oximetry-derived indices (p = 0.4528, p = 0.2715, respectively). Conclusions: Our results suggest that disturbed cerebral metabolism reflects a vulnerable brain which may be more susceptible to overperfusion during CPB, which can be seen in increased MCAV values. These phenomena occur irrespectively of cerebral autoregulation. Full article

In 2015, Catalonia introduced sickle cell disease (SCD) screening in its newborn screening (NBS) program along with standard-of-care treatments like penicillin, hydroxyurea, and anti-pneumococcal vaccination. Few studies have assessed the clinical impact of introducing NBS programs on SCD patients. We analyzed the incidence of SCD and related hemoglobinopathies in Catalonia and the change in clinical events occurring after introducing NBS. Screening 506,996 newborns from 2015 to 2022, we conducted a retrospective multicenter study including 100 screened (SG) and 95 unscreened (UG) SCD patients and analyzed SCD-related clinical events over the first six years of life. We diagnosed 160 cases of SCD, with an incidence of 1 in 3169 newborns. The SG had a significantly lower median age at diagnosis (0.1 y vs. 1.68 y, p < 0.0001), and initiated penicillin prophylaxis (0.12 y vs. 1.86 y, p < 0.0001) and hydroxyurea treatment earlier (1.42 y vs. 4.5 y, p < 0.0001). The SG experienced fewer median SCD-related clinical events (vaso-occlusive crisis, acute chest syndrome, infections of probable bacterial origin, acute anemia requiring transfusion, acute splenic sequestration, and pathological transcranial Doppler echography) per year of follow-up (0.19 vs. 0.77, p < 0.0001), a reduced number of annual emergency department visits (0.37 vs. 0.76, p < 0.0001), and fewer hospitalizations (0.33 vs. 0.72, p < 0.0001). SCD screening in Catalonia’s NBS program has effectively reduced morbidity and improved affected children’s quality of life. Full article

Background/Objectives The purpose of this study was to see whether there is a correlation between the behavior of autism spectrum disorder patients and brain abnormalities based on the velocity of blood flow in the MCA (middle cerebral artery). Methods: The use of HAP (High Altitude Protection) suits, which are used in aviation, to treat patients with ASD (autism spectrum disorder) causes significant changes in their functioning and physiological processes. These changes are not only noted in psychological tests but are observed in cerebral blood flow using transcranial Doppler ultrasound of the MCA. Results The results of this study made it possible to distinguish two groups with different flow velocities, which can be characterized as flows of less than 80 cm/s and flows of more than 80 cm/s. In addition, it was shown that in patients with elevated blood flow velocity, aggressive behaviors account for 86.96%, while self-aggressive behaviors account for 65.2%. On the other hand, in the case of patients with reduced flow velocity, i.e., less than 80 cm/s, the rate of aggressive behavior is 20% and that of self-aggressive behavior is 50%. The experiment showed that after therapy, there is a normalization of blood flow, which increased in the case of patients with a reduced flow rate below 80 cm/s and, in the case of elevated blood velocity after therapy, decreased towards normal levels. Conclusions The observed rate of normalization of flow velocities in the MCA translated into significant changes in the behavior and functioning of patients in the neurotypical direction, which was noticeable in the psychological tests conducted. Full article

We assessed the feasibility of concurrent monitoring of cerebral hemodynamics in adult, comatose out-of-hospital cardiac arrest (OHCA) patients admitted to the National University Heart Centre Singapore from October 2021 to August 2023. Patients underwent continuous near-infrared spectroscopy (NIRS) monitoring in the first 72 h after return of spontaneous circulation (ROSC) and 30-min transcranial Doppler ultrasound (TCD) monitoring at least once. With constant mechanical ventilatory settings and continuous electrocardiographic, pulse oximeter and end-tidal carbon dioxide monitoring, blood pressure was manipulated via vasopressors and cerebral autoregulation assessed by measuring changes in regional cerebral oxygenation (NIRS) and cerebral blood flow velocities (TCD) in response to changes in mean arterial pressure. The primary outcome was neurological recovery at hospital discharge. Amongst the first 16 patients (median age 61, 94% males), we observed four unique patterns: preserved cerebral autoregulation, loss of cerebral autoregulation, cardio-cerebral asynchrony and cerebral circulatory arrest. Patients with preserved cerebral autoregulation had lower levels of neuro-injury biomarkers (neurofilaments light and heavy) and the majority (86%) were discharged with good neurological recovery. Multi-modal assessment of cerebral hemodynamics after OHCA is feasible and derived patterns correlated with neurological outcomes. The between- and within-patient heterogeneity in cerebral hemodynamics calls for more research on individualized treatment strategies. Full article