Cervical internal carotid artery fenestration: a rare cause of lumen "dissection''.

PURPOSE: To highlight the clinical and diagnostic importance of correctly identifying cervical internal carotid artery fenestration (fcICA), an extremely rare vascular anomaly, and to present a case where fcICA was initially misdiagnosed as a dissection in a patient with fibromuscular dysplasia (FMD). METHODS: A 47-year-old woman with pulsatile tinnitus underwent computed tomography angiography (CTA) and digital subtraction angiography (DSA) to differentiate between fenestration and dissection of the internal carotid artery. RESULTS: CTA revealed a fusiform dilatation of the distal C1 segment of the right internal carotid artery (ICA) with a linear filling defect, suggesting either fenestration or dissection. DSA confirmed the presence of a fenestrated right ICA segment composed of two symmetrical, smooth-walled limbs without a dissection flap, along with signs of FMD in the proximal vessel. The patient's symptoms were attributed to local flow perturbations induced by fcICA and FMD. CONCLUSION: This case illustrates that fcICA can be a true anatomical variant rather than a result of dissection, emphasizing the need for accurate imaging and diagnosis to avoid unnecessary treatments. The coexistence of fcICA with FMD increases the risk of dissection, necessitating careful monitoring. The distinction between fenestration and pseudofenestration remains challenging, requiring comprehensive imaging and close collaboration between radiologists and vascular neurologists.

The Experience of a Tertiary Reference Hospital in the Study of Rare Neurological Diseases.

Background and Objectives: Rare diseases (RDs) are life-threatening or chronically impairing conditions that affect about 6% of the world's population. RDs are often called 'orphan' diseases, since people suffering from them attract little support from national health systems. Aim: The aim of this study is to describe the clinical characteristics of, and the available laboratory examinations for, patients who were hospitalized in a tertiary referral center and finally received a diagnosis associated with a Rare Neurological Disease (RND). Materials and Methods: Patients that were hospitalized in our clinic from 1 January 2014 to 31 March 2022 and were finally diagnosed with an RND were consecutively included. The RND classification was performed according to the ORPHAcode system. Results: A total of 342 out of 11.850 (2.9%) adult patients admitted to our department during this period received a diagnosis associated with an RND. The most common diagnosis (N = 80, 23%) involved an RND presenting with dementia, followed by a motor neuron disease spectrum disorder (N = 64, 18.7%). Family history indicative of an RND was present in only 21 patients (6.1%). Fifty-five (16%) people had previously been misdiagnosed with another neurological condition. The mean time delay between disease onset and diagnosis was 4.24 ± 0.41 years. Conclusions: Our data indicate that a broad spectrum of RNDs may reach a tertiary Neurological Center after a significant delay. Moreover, our data underline the need for a network of reference centers, both at a national and international level, expected to support research on the diagnosis and treatment of RND.

CADASIL in Greece: Mutational spectrum and clinical characteristics based on a systematic review and pooled analysis of published cases.

BACKGROUND: Differences have been noted in the clinical presentation and mutational spectrum of CADASIL among various geographical areas. The aim of the present study was to investigate the mode of clinical presentation and genetic mutations reported in Greece. METHODS: After a systematic literature search, we performed a pooled analysis of all published CADASIL cases from Greece. RESULTS: We identified 14 studies that reported data from 14 families comprising 54 patients. Migraine with aura was reported in 39%, ischemic cerebrovascular diseases in 68%, behavioral-psychiatric symptoms in 47% and cognitive decline in 60% of the patients. The mean (±SD) age of onset for migraine with aura, ischemic cerebrovascular diseases, behavioral-psychiatric symptoms and cognitive decline was 26.2 ± 8.7, 49.3 ± 14.6, 47.9 ± 9.4 and 42.9 ± 10.3, respectively; the mean age at disease onset and death was 34.6 ± 12.1 and 60.2 ± 11.2 years. With respect to reported mutations, mutations in exon 4 were the most frequently reported (61.5% of all families), with the R169C mutation being the most common (30.8% of all families and 50% of exon 4 mutations), followed by R182C mutation (15.4% of all families and 25% of exon 4 mutations). CONCLUSIONS: The clinical presentation of CADASIL in Greece is in accordance with the phenotype encountered in Caucasian populations, but differs from the Asian phenotype, which is characterized by a lower prevalence of migraine and psychiatric symptoms. The genotype of Greek CADASIL pedigrees is similar to that of British pedigrees, exhibiting a high prevalence of exon 4 mutations, but differs from Italian and Asian populations, where mutations in exon 11 are frequently encountered.

Greater decline of acute stroke admissions compared with acute coronary syndromes during COVID-19 outbreak in Greece: Cerebro/cardiovascular implications amidst a second wave surge.

BACKGROUND AND PURPOSE: A remarkable decline in admissions for acute stroke and acute coronary syndrome (ACS) has been reported in countries severely hit by the COVID-19 pandemic. However, limited data are available from countries with less COVID-19 burden focusing on concurrent stroke and ACS hospitalisation rates from the same population. METHODS: The study was conducted in three geographically and demographically representative COVID-19 referral university hospitals in Greece. We recorded the rate of stroke and ACS hospital admissions during a 6-week period of the COVID-19 outbreak in 2020 and compared them with the rates of the corresponding period in 2019. RESULTS: We found a greater relative reduction of stroke admissions (51% [35 vs. 71]; incidence rate ratio [IRR]: 0.49, p = 0.001) compared with ACS admissions (27% [123 vs. 168]; IRR: 0.73, p = 0.009) during the COVID-19 outbreak (p = 0.097). Fewer older (>65 years) patients (stroke: 34.3% vs. 45.1%, odds ratio [OR]: 0.64, p = 0.291; ACS: 39.8% vs. 54.2%, OR: 0.56, p = 0.016) were admitted during the COVID-19 compared with the control period. CONCLUSIONS: Hospitalisation rates both for stroke and ACS were reduced during the COVID-19 outbreak in a country with strict social distancing measures, low COVID-19 incidence and low population mortality. Lack of triggers for stroke and ACS during social distancing/quarantining may explain these observations. However, medical care avoidance attitudes among cerebro/cardiovascular patients should be dissipated amidst the rising second COVID-19 wave.

"Radiologically Isolated" Spinal Cavernoma Associated with Familial Cerebral Cavernomatosis.

We describe a 45 year-old woman with a randomly discovered cavernous malformation of the cervical cord following investigation for neck injury. She had multiple brain cavernomas increasing in number over the following two years. She was finally diagnosed with familial cavernomatosis due to a PDCD10 mutation (CCM3).

Risk of major adverse cardiovascular events and stroke associated with treatment with GLP-1 or the dual GIP/GLP-1 receptor agonist tirzepatide for type 2 diabetes: A systematic review and meta-analysis.

INTRODUCTION: Mounting evidence suggests that glucagon-like-peptide-1 receptor-agonists (GLP-1 RAs) attenuate cardiovascular-risk in type-2 diabetes (T2DM). Tirzepatide is the first-in-class, dual glucose-dependent-insulinotropic-polypeptide GIP/GLP-1 RA approved for T2DM. PATIENTS AND METHODS: A systematic review and meta-analysis of randomized-controlled clinical trials (RCTs) was performed to estimate: (i) the incidence of major adverse cardiovascular events (MACE); and (ii) incidence of stroke, fatal, and nonfatal stroke in T2DM-patients treated with GLP-1 or GIP/GLP-1 RAs (vs placebo). RESULTS: Thirteen RCTs (9 and 4 on GLP-1 RAs and tirzepatide, respectively) comprising 65,878 T2DM patients were included. Compared to placebo, GLP-1RAs or GIP/GLP-1 RAs reduced MACE (OR: 0.87; 95% CI: 0.81-0.94; p < 0.01; I2 = 37%), all-cause mortality (OR: 0.88; 95% CI: 0.82-0.96; p < 0.01; I2 = 21%) and cardiovascular-mortality (OR: 0.88; 95% CI: 0.80-0.96; p < 0.01; I2 = 14%), without differences between GLP-1 versus GIP/GLP-1 RAs. Additionally, GLP-1 RAs reduced the odds of stroke (OR: 0.84; 95% CI: 0.76-0.93; p < 0.01; I2 = 0%) and nonfatal stroke (OR: 0.85; 95% CI: 0.76-0.94; p < 0.01; I2 = 0%), whereas no association between fatal stroke and GLP-1RAs was uncovered (OR: 0.80; 95% CI: 0.61-1.05; p = 0.105; I2 = 0%). In secondary analyses, GLP-1 RAs prevented ischemic stroke (OR: 0.74; 95% CI: 0.61-0.91; p < 0.01; I2 = 0%) and MACE-recurrence, but not hemorrhagic stroke (OR: 0.92; 95% CI: 0.51-1.66; p = 0.792; I2 = 0%). There was no association between GLP-1RAs or GIP/GLP-1 RAs and fatal or nonfatal myocardial infarction. DISCUSSION AND CONCLUSION: GLP-1 and GIP/GLP-1 RAs reduce cardiovascular-risk and mortality in T2DM. While there is solid evidence that GLP-1 RAs significantly attenuate the risk of ischemic stroke in T2DM, dedicated RCTs are needed to evaluate the efficacy of novel GIP/GLP-1 RAs for primary and secondary stroke prevention.

Paraneoplastic Neurological Syndromes as Initial Presentation of Tumors: An Eight-Year Single-Center Experience.

BACKGROUND: Paraneoplastic Neurological Syndromes (PNS) comprise a diverse group of disorders propagated by immune-mediated effects of malignant tumors on neural tissue. METHODS: A single-center longitudinal study was performed including consecutive adult patients treated at a tertiary academic hospital between 2015 and 2023 and diagnosed with PNS. PNS were ascertained using the 2004 and the revised 2021 PNS-Care diagnostic criteria. RESULTS: Thirteen patients who fulfilled the 2004 definite PNS criteria were included. PNS comprise diverse neurological syndromes, with neuromuscular junction disorders (54%) and limbic encephalitis (31%) being predominant. PNS-related antibodies were detected in 85% of cases, including anti-AChR (n = 4), anti-P/Q-VGCC (n = 3), anti-Hu (n = 3), anti-Yo (n = 1), anti-Ma (n = 1), anti-titin (n = 1), anti-IgLON5 (n = 1), and anti-GAD65 (n = 1). Thymoma (31%), small-cell lung cancer (23%), and papillary thyroid carcinoma (18%) were the most frequent tumors. Imaging abnormalities were evident in 33% of cases. Early immunotherapy within 4-weeks from symptom onset was associated with favorable outcomes. At a mean follow-up of 2 ± 1 years, two patients with anti-Hu and anti-Yo antibodies died (18%). Four and three patients fulfilled the 2021 PNS-Care diagnostic criteria for definite and probable PNS, respectively. CONCLUSIONS: This study highlights the clinical heterogeneity of PNS, emphasizing the need for early suspicion and prompt treatment initiation for optimal outcomes.

CSF and plasma biomarkers in cerebral amyloid angiopathy: A single-center study and a systematic review/meta-analysis.

INTRODUCTION: There are limited data regarding cerebrospinal fluid (CSF) and plasma biomarkers among patients with Cerebral Amyloid Angiopathy (CAA). We sought to investigate the levels of four biomarkers [ß-amyloids (Aß42 and Aß40), total tau (tau) and phosphorylated tau (p-tau)] in CAA patients compared to healthy controls (HC) and patients with Alzheimer Disease (AD). PATIENTS AND METHODS: A systematic review and meta-analysis of published studies, including also a 5 year single-center cohort study, with available data on CSF and plasma biomarkers in symptomatic sporadic CAA versus HC and AD was conducted. Biomarkers' comparisons were investigated using random-effects models based on the ratio of mean (RoM) biomarker concentrations. RoM < 1 and RoM > 1 indicate lower and higher biomarker concentration in CAA compared to another population, respectively. RESULTS: We identified nine cohorts, comprising 327 CAA patients (mean age: 71 ± 5 years; women: 45%) versus 336 HC (mean age: 65 ± 5 years; women: 45%) and 384 AD patients (mean age: 68 ± 3 years; women: 53%) with available data on CSF biomarkers. CSF Aß42 levels [RoM: 0.47; 95% CI: 0.36-0.62; p < 0.0001], Aß40 levels [RoM: 0.70; 95% CI: 0.63-0.79; p < 0.0001] and the ratio Aß42/Aß40 [RoM: 0.62; 95% CI: 0.39-0.98; p = 0.0438] differentiated CAA from HC. CSF Aß40 levels [RoM: 0.73; 95% CI: 0.64-0.83; p = 0.0003] differentiated CAA from AD. CSF tau and p-tau levels differentiated CAA from HC [RoM: 1.71; 95% CI: 1.41-2.09; p = 0.0002 and RoM: 1.44; 95% CI: 1.20-1.73; p = 0.0014, respectively] and from AD [RoM: 0.65; 95% CI: 0.58-0.72; p < 0.0001 and RoM: 0.64; 95% CI: 0.57-0.71; p < 0.0001, respectively]. Plasma Aß42 [RoM: 1.14; 95% CI: 0.89-1.45; p = 0.2079] and Aß40 [RoM: 1.07; 95% CI: 0.91-1.25; p = 0.3306] levels were comparable between CAA and HC. CONCLUSIONS: CAA is characterized by a distinct CSF biomarker pattern compared to HC and AD. CSF Aß40 levels are lower in CAA compared to HC and AD, while tau and p-tau levels are higher in CAA compared to HC, but lower in comparison to AD patients.

Quality metrics in the management of acute stroke in Greece during the first 5 years of Registry of Stroke Care Quality (RES-Q) implementation.

Introduction: Establishment of a prospective stroke registry may promote the documentation and improvement of acute stroke care. We present the status of stroke management in Greece using the Registry of Stroke Care Quality (RES-Q) dataset. Methods: Consecutive patients with acute stroke were prospectively registered in RES-Q registry by contributing sites in Greece during the years 2017-2021. Demographic and baseline characteristics, acute management, and clinical outcomes at discharge were recorded. Stroke quality metrics, with a specific interest in the association between acute reperfusion therapies and functional recovery in ischemic stroke patients are presented. Results: A total of 3590 acute stroke patients were treated in 20 Greek sites (61% men, median age 64 years; median baseline NIHSS 4; 74% ischemic stroke). Acute reperfusion therapies were administered in almost 20% of acute ischemic stroke patients, with a door to needle and door to groin puncture times of 40 and 64 min, respectively. After adjustment for contributing sites, the rates of acute reperfusion therapies were higher during the time epoch 2020-2021 compared to 2017-2019 (adjusted OR 1.31; 95% CI 1.04-1.64; p < 0.022; Cochran-Mantel-Haenszel test). After propensity-score-matching, acute reperfusion therapies administration was independently associated with higher odds of reduced disability (one point reduction across all mRS scores) at hospital discharge (common OR 1.93; 95% CI 1.45-2.58; p < 0.001). Conclusions: Implementation and maintenance of a nationwide stroke registry in Greece may guide the stroke management planning, so that prompt patient transportation, acute reperfusion therapies, and stroke unit hospitalization become more widely accessible, improving the functional outcomes of stroke patients.

Advances in Noninvasive Carotid Wall Imaging with Ultrasound: A Narrative Review.

Carotid atherosclerosis is a major cause for stroke, with significant associated disease burden morbidity and mortality in Western societies. Diagnosis, grading and follow-up of carotid atherosclerotic disease relies on imaging, specifically ultrasound (US) as the initial modality of choice. Traditionally, the degree of carotid lumen stenosis was considered the sole risk factor to predict brain ischemia. However, modern research has shown that a variety of other imaging biomarkers, such as plaque echogenicity, surface morphology, intraplaque neovascularization and vasa vasorum contribute to the risk for rupture of carotid atheromas with subsequent cerebrovascular events. Furthermore, the majority of embolic strokes of undetermined origin are probably arteriogenic and are associated with nonstenosing atheromas. Therefore, a state-of-the-art US scan of the carotid arteries should take advantage of recent technical developments and should provide detailed information about potential thrombogenic (/) and emboligenic arterial wall features. This manuscript reviews recent advances in ultrasonographic assessment of vulnerable carotid atherosclerotic plaques and highlights the fields of future development in multiparametric arterial wall imaging, in an attempt to convey the most important take-home messages for clinicians performing carotid ultrasound.

Off-label intravenous thrombolysis for early recurrent brain embolism associated with aortic arch thrombus.

Safety data of intravenous thrombolysis (IVT) in presence of aortic arch thrombus is scant. Furthermore, IVT is debatable in patients with prior recent stroke. We present a 51-year-old woman with recurrent major infarction 5 days after a minor left MCA territory stroke. She had a floating aortic arch thrombus and she was treated safely and effectively with off-label IVT. Patients with small infarct volumes and mild/no residual neurological deficits after an initial stroke might be considered for IVT in case of early recurrence. IVT may be reasonable in a context of acute severely disabling stroke associated with aortic arch thrombus.

Long-Term Efficacy Outcomes of Natalizumab vs. Fingolimod in Patients With Highly Active Relapsing-Remitting Multiple Sclerosis: Real-World Data From a Multiple Sclerosis Reference Center.

Background: Natalizumab (NTZ) and fingolimod (FTY) are second-line disease modifying treatments (DMTs) approved for Relapsing - Remitting Multiple Sclerosis (RRMS). Few studies are available on a direct comparison between NTZ and FTY, based on post-marketing experience, with conflicting results and reporting relatively short follow-up period. Aim: We hereby report real-world experience of a MS Center with respect to NTZ vs. FTY comparison in terms of efficacy and safety, referencing long-term follow-up. Methods: We used retrospective data for all patients that received 2nd-line treatment NTZ (since May 2007) or FTY (since September 2011). Primary endpoints were, among others, annual EDSS score (mean change from baseline), time to disability worsening or improvement, Annualized Relapse Rate (ARR) after 12 and 24 months and upon total treatment duration, time to first relapse and time to radiological progression. Results: A total of 138 unmatched patients, 84 treated with NTZ and 54 treated with FTY were included. Following Propensity Score (PS) matching, 31 patients in each group were retained. Mean follow-up period for NTZ- and FTY-treated patients was 4.43 ± 0.29 and 3.59 ± 0.32 years (p = 0.057), respectively. In the matched analysis, time to disability improvement and time to disability worsening was comparable between groups. A higher proportion of patients remained free of relapse under NTZ, compared to FTY (Log Rank test p = 0.021, HR: 0.25, 95% CI: 0.08-0.8), as well as free of MRI activity (Log Rank test p = 0.006, HR: 0.26, 95% CI: 0.08-0.6). Treatment discontinuation due to MRI activity was significantly higher for FTY-treated patients compared to NTZ (Log Rank test p = 0.019, HR: 0.12, 95% CI: 0.05-0.76). Conclusion: Our results indicate toward NTZ superiority with respect to relapse and MRI activity outcomes. The fact that NTZ-treated patients may achieve long-standing clinical and radiological remission points toward the need for long follow-up data.

Persistent decline of hospitalizations for acute stroke and acute coronary syndrome during the second wave of the COVID-19 pandemic in Greece: collateral damage unaffected.

BACKGROUND: An alarming cerebro/cardiovascular collateral damage, reflected by a decline in admissions for acute stroke (AS) and acute coronary syndrome (ACS), was observed during the initial phase of the COVID-19 pandemic, thereby leading to a re-design of public campaigns. However, there are limited data regarding the AS and ACS hospitalization rates during the second wave of the pandemic, which was followed by re-imposition of lockdowns. METHODS: We calculated the rate of AS and ACS hospitalizations from three representative tertiary care hospitals in Greece during a 2-month period (November-December 2020) of the second wave of the COVID-19 pandemic compared with the corresponding control period in 2019 from three representative tertiary care hospitals in Greece. This was a follow-up study with identical design to our previous report evaluating AS and ACS hospitalizations during the first wave of the pandemic (March-April 2020). RESULTS: Compared with 2019, there was a 34% relative reduction of AS hospitalizations [incidence rate ratio (IRR): 0.66, 95% confidence interval (CI): 0.48-0.92, p = 0.013] and 33% relative reduction of ACS hospitalizations (IRR: 0.67, 95% CI: 0.54-0.83, p < 0.001) during the second wave of the COVID-19 pandemic. The relative reduction was smaller and did not reach the level of statistical significance for the respective syndromes (haemorrhagic stroke: IRR 0.87, 95% CI: 0.41-1.82, p = 0.71; ST-elevation myocardial infarction: IRR 0.81, 95% CI: 0.57-1.14, p = 0.22). CONCLUSION: AS and ACS hospitalizations were persistently reduced during the second wave of the COVID-19 pandemic compared with 2019 in Greece. This decline was similar to the observations during the first wave despite the large differences in the epidemiological COVID-19 burden. Lockdowns, a common characteristic in both waves, appear to have a detrimental indirect impact on cerebro/cardiovascular diseases in the general population.

Prevalence of patent foramen ovale in the Greek population is high and impacts on the interpretation of the risk of paradoxical embolism (RoPE) score.

BACKGROUND: The risk of paradoxical embolism (RoPE) score calculates the probability that patent foramen ovale (PFO) is causally related to stroke (PFO attributable fraction, PFOAF), based on PFO prevalence in patients with cryptogenic stroke (CS) compared with that in the general population. The latter has been estimated at 25%; however, PFO prevalence in nonselected populations varies widely. METHODS: Since PFO prevalence in Greece remains unknown, we evaluated it and we calculated PFOAF stratified by RoPE score in a cohort of patients with CS ⩽55 years old. PFO was detected according to the international consensus transcranial Doppler (TCD) criteria in 124 healthy subjects (H), in 102 patients with CS, and in 56 patients with stroke of known cause (nonCS). Each subject underwent unilateral middle cerebral artery recording after infusion of agitated saline, at rest, and after a controlled Valsalva maneuver. We characterized PFO as large (>20 microbubbles or curtain), moderate (11-20), and small (⩽10). RESULTS: PFO was detected in 42.7% of H, 49% of CS, and 25% of nonCS (p = 0.013). Large PFOs were numerically higher in CS [28.4% (29/102)] compared with H [19.3% (24/124); p = 0.1] and to nonCS [7.1% (4/56), p = 0.04]. The median RoPE score in patients with CS and PFO was seven. Even patients with very high RoPE score (9-10) had moderate PFOAF (57%). For any individual stratum up to RopE score 8, PFOAF was <33%. CONCLUSIONS: PFO prevalence in the Greek population is much higher than the widely accepted 25%. PFO may be the cause of stroke in one out of nine Greek patients with CS. Among Greek CS patients who harbor a PFO, the latter is causal in one out of five. The established RoPE score cutoff of ⩾7 for having a probable PFO-associated stroke may overestimate the probability in patients deriving from populations with high PFO prevalence.

Epidemiology of Patent Foramen Ovale in General Population and in Stroke Patients: A Narrative Review.

Introduction: Percutaneous closure of patent foramen ovale (PFO) in selected patients with cryptogenic cerebrovascular ischemic events (CEs) decreases the risk of recurrent stroke; however, optimal patient selection criteria are still under investigation. Candidates for PFO closure are usually selected from the pool of CE patients with a high risk of Paradoxical Embolism (RoPE) score. The RoPE score calculates the probability that PFO is causally related to stroke, based on PFO prevalence in patients with CE compared with that in healthy subjects. The latter has been set at 25% based on the average of autopsy and transesophageal echocardiography (TEE) studies. Methods: We conducted a comprehensive review of studies investigating PFO prevalence in general population and in patients with CE and non-CE using autopsy, TEE, transcranial Doppler (TCD) or transthoracic echocardiography (TTE). Studies were excluded if they (1) reported data from referred subjects with underlying cerebrovascular disease or (2) did not specify etiologically the events. Results: In healthy/control subjects, PFO prevalence was 24.2% (1,872/7,747) in autopsy studies, 23.7% (325/1,369) in TEE, 31.3% (111/355) in TCD, and 14.7% (186/1,267) in TTE studies. All diagnostic modalities included PFO prevalence was higher in CE compared with healthy/control population [odds ratio (OR) = 3.1, 95% confidence interval (CI) = 2.5-3.8] and compared with non-CE (OR = 2.3, 95% CI = 2.0-2.6). In patients with CE, PFO prevalence in the young compared to the old was higher when the diagnostic modality was TEE (48.9 vs. 27.3%, p < 0.0001, OR = 2.6 with 95% CI = 2.0-3.3) or TCD (58.1 vs. 41%, OR = 1.9, 95% CI = 1.6-2.5), but not TTE (53.3 vs. 37.5%, p = 0.16). Regarding non-CE, PFO prevalence in the young compared to the old was higher when the diagnostic modality was TEE (20 vs. 12.9%, OR = 1.7, 95% CI = 1.0-2.8) but not TTE (10.4 vs. 7.8%, p = 0.75) or TCD (22.8 vs. 20.1%, p = 0.56). Conclusions: Given the limitations of autopsy and TEE studies, there is good reason not to take a fixed 25% PFO prevalence for granted. The estimation of degree of causality may be underestimated or overestimated in populations with PFO prevalence significantly lower or higher than the established. Given the high sensitivity, non-invasive nature, low cost, and repeatability of TCD, future large-scale TCD-based studies should investigate potential heterogeneity in PFO prevalence in different healthy racial/ethnic populations.

Functional Neurosonology Reveals Impaired Cerebrovascular Reactivity in Multiple Sclerosis.

BACKGROUND AND PURPOSE: Vascular aspects like global cerebral hypoperfusion are frequently reported in patients with multiple sclerosis (MS). Although mechanistic question remains unanswered, this hemodynamic impairment may be caused by a widespread endothelial dysfunction. Furthermore, impaired cerebrovascular reactivity (CVR) has been described in patients with MS by means of hypercapnic perfusion magnetic resonance imaging (MRI). We sought to further evaluate potential hemodynamic restriction in patients with MS using functional sonographic methods. METHODS: We evaluated consecutive patients with MS and healthy controls with adequate bilateral transtemporal window. CVR was assessed by bilateral transcranial Doppler monitoring of proximal middle cerebral arteries. Mean flow velocities were recorded before and after 30 seconds of breath holding. Vasomotor response was quantified by breath holding index (BHI). RESULTS: A total of 42 patients with MS (mean age 39 ± 12 years; 69% women) were compared to 31 healthy controls (mean age 35 ± 11 years; 71% women). BHI was lower in patients with MS compared to healthy controls (.70 ± .43 vs. .93 ± .55; P = .006), documenting a lower cerebrovascular response to hypercapnia. There was no correlation between patient age (r = .1254; P = .277), expanded disability status scale (r = .1838; P = .109), and disease duration (r = .1882; P = .101) with BHI in patients with MS. CONCLUSIONS: These preliminary sonographic findings appear to independently corroborate the previously reported observation of impaired CVR on brain MRI in patients with MS. However, the underlying pathophysiological mechanisms as well as the clinical impact of this observation remain elusive.