129 research outputs found
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Imaging techniques in ALS.
Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease characterized by degeneration of both upper and lower motor neuron located in the spinal cord and brainstem. Diagnosis of ALS is predominantly clinical, nevertheless, electromyography and Magnetic Resonance Imaging (MRI) may provide support. Several advanced MRI techniques have been proven useful for ALS diagnosis and, indeed, the combination of different MRI techniques demonstrated an improvement in sensitivity and specificity as far as 90%. This review focus on the imaging techniques currently used in the diagnosis and management of ALS with brief considerations on future applications
Multiple sclerosis: changes in microarchitecture of white matter tracts after training with a video game balance board
Purpose: To determine if high-intensity, task-oriented, visual feedback training with a video game balance board (Nintendo Wii) induces significant changes in diffusion-tensor imaging (DTI) parameters of cerebellar connections and other supratentorial associative bundles and if these changes are related to clinical improvement in patients with multiple sclerosis.Conclusion: Despite the low statistical power (35%) due to the small sample size, the results showed that training with the balance board system modified the microstructure of superior cerebellar peduncles. The clinical improvement observed after training might be mediated by enhanced myelinationrelated processes, suggesting that high-intensity, taskoriented exercises could induce favorable microstructural changes in the brains of patients with multiple sclerosis.Materials and Methods: The protocol was approved by local ethical committee; each participant provided written informed consent. In this 24-week, randomized, two-period crossover pilot study, 27 patients underwent static posturography and brain magnetic resonance (MR) imaging at study entry, after the first 12-week period, and at study termination. Thirteen patients started a 12-week training program followed by a 12-week period without any intervention, while 14 patients received the intervention in reverse order. Fifteen healthy subjects also underwent MR imaging once and underwent static posturography. Virtual dissection of white matter tracts was performed with streamline tractography; values of DTI parameters were then obtained for each dissected tract. Repeated measures analyses of variance were performed to evaluate whether DTI parameters significantly changed after intervention, with false discovery rate correction for multiple hypothesis testing.Results: There were relevant differences between patients and healthy control subjects in postural sway and DTI parameters (P <.05). Significant main effects of time by group interaction for fractional anisotropy and radial diffusivity of the left and right superior cerebellar peduncles were found (F2,23 range, 5.555-3.450; P = .036-.088 after false discovery rate correction). These changes correlated with objective measures of balance improvement detected at static posturography (r = 20.381 to 0.401, P < .05). However, both clinical and DTI changes did not persist beyond 12 weeks after training
Periventricular Lesions Help Differentiate Neuromyelitis Optica Spectrum Disorders from Multiple Sclerosis
Objective. To compare periventricular lesions in multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOsd). Materials and Methods. Sagittal and axial fluid attenuated inversion recovery (FLAIR) sequences of 20 NMOsd and 40 group frequency-matched MS patients were evaluated by two neuroradiologists. On axial FLAIR, periventricular area was characterized as free of lesions/smooth-bordered (“type A”) or jagged-bordered (“type B”) pattern. On sagittal FLAIR, the images were evaluated for presence of “Dawson's fingers.” Results. Type A pattern was observed in 80% of NMOsd patients by Reader 1 and 85% by Reader 2 but only in 5% MS patients by either Reader. Type B was seen in 15% NMOsd patients by Reader 1 and 20% by Reader 2 and in 95% MS patients by either Reader. Dawson's fingers were observed in no NMOsd patients by Reader 1 and 5% by Reader 2. In MS, Dawson's fingers were seen in 92.5% patients by Reader 1 and 77.5% by Reader 2. The differences in periventricular patterns and Dawson's finger detection between NMOsd and MS were highly significant (P < 0.001). Conclusions. Dawson's fingers and “jagged-bordered” periventricular hyperintensities are typical of MS and almost never seen in NMOsd, which suggests a practical method for differentiating the two diseases
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In and around the optic chiasm: a pictorial review of neuroimaging
The optic chiasm is a key anatomical structure along the visual pathway, situated at the crossroads between optic nerves and tracts. A wide range of diseases can affect the optic chiasm and its surrounding strategic region at the base of the brain. Management strategies for optic chiasm abnormalities vary substantially, depending on the abnormalities revealed on neuroimaging. Scant attention has been paid to date to comprehensive classification of neuroimaging manifestations of optic chiasm abnormalities. We comprehensively review and present the imaging findings in a wide spectrum of pathologies originating from or involving the optic chiasm. This review will aid in differentiating the many neuroimaging appearances of lesions in this region
Association between carotid artery and abdominal aortic aneurysm plaque
The correlation between AAA and carotid artery plaque is unknown and a common etiology and pathophysiology is suspected by some authors. The purpose of this work was to explore the association between the features of a) carotid artery plaque and b) abdominal aortic aneurysm (AAA) plaques using multi-detector-CT Angiography (MDCTA). Forty-eight (32 males; median age 72 years) patients studied using a 16-detectors CT scanner were retrospectively analyzed. A region of interest (ROI) ≥ 2 mm2 was used to quantify the HU value of the plaque by two readers independently. Inter-observer reproducibility was calculated and Pearson correlation analysis was performed. The Bland-Altman plots showed the inter-observer reproducibility to be good. The Pearson correlation was 0.224 (95 % CI = 0.071 to 0.48), without statistically significant association between HU measured in the carotid artery plaque and in the AAA plaques (p = 0.138); after exclusion of the calcified plaques from the analysis, the rho values resulted 0.494 (95 % CI = 0.187 to 0.713) with a statistically significant association (p = 0.003). In this study, we found an association between the features of the non calcific carotid plaque and the features of AAA plaque
Intrasaccular Flow Disruptor-Assisted Coiling of Intracranial Aneurysms Using the Novel Contour Neurovascular Systems and NEQSTENT: A Single-Center Safety and Feasibility Study
Brain aneurysms; Endovascular treatment; Intrasaccular devicesAneurismas cerebrales; Tratamiento endovascular; Dispositivos intrasacularesAneurismes cerebrals; Tractament endovascular; Dispositius intrasacularsBackground: Intrasaccular flow disruptors (IFD) have been introduced in the treatment of intracranial aneurysms (IAs) to overcome the low aneurysm occlusion rate and the high recanalization rate of the coiling technique. Among them, the Contour Neurovascular System (CNS) and the Neqstent (NQS) were designed to reconstruct the aneurysmal neck and both can be used as assisting coiling devices. We aimed to report our preliminary experience with the flow disruptor-assisted coiling (IFD-AC) technique. Methods: We performed a retrospective analysis of prospectively collected data of all patients with IAs treated with the IFD-AC. Results: Between February 2021 and April 2022, we treated 15 IAs with the IFD-AC: 10 ruptured and 5 unruptured. The IFD-AC was successfully performed in 13 cases, with a post-operative RROC 1 in 12 cases (92.3%) and RROC 2 in 1 case (7.7%). There was one ischemic event (6.7%) and no hemorrhagic complications. Twelve patients underwent a mid-term radiologic follow-up: Ten IAs (83.4%) presented an adequate occlusion, while 2 (16.7%) had a recurrence. Conclusions: The IFD-AC, both with the CNS and the NQS, seems a safe technique with promising efficacy profile. The IFD-AC has proved to be safe without antiplatelet therapy in ruptured cases. Further studies are needed to confirm our preliminary results
fMRI in Bell's Palsy: cortical activation is associated with clinical status in the acute and recovery phases
BACKGROUND: Using functional MRI (fMRI), we explored cortical activation in patients with acute
Bell’s palsy (BP) and analyzed its correlates with clinical status in the acute phase, and with 6-monthoutcome.
METHODS: 24 right-handed patients with acute BP within 15 days of onset and 24 healthy controls
underwent fMRI during performance of unilateral active (hemi-smiling) and passive lip movement tasks
with both the paretic and the normal lip. The degree of paresis was evaluated during the acute stage and
at the 6-month follow-up using the House-Brackmann (HB) grading scale. Complete recovery was
defined as HB grade II or less at the end of the 6-month period. The difference in the HB grade (ΔHB)
between the acute stage and the 6-month follow up was used to evaluate clinical improvement.
RESULTS: There were 24 patients with unilateral acute BP. HB grades ranged from III to VI. At six
months, 11 patients (46%) had completely recovered and 12 (50%) were partially improved. Compared
with healthy subjects, BP patients had a significantly greater activation of the frontal areas and the insula
ipsilateral to the paretic side. In BP patients, there was an inverse correlation between the activation of
the ipsilateral hemisphere when moving the paretic side and the degree of paresis at baseline. An
association was also observed between activation and clinical outcome (both complete recovery and
ΔHB).
CONCLUSIONS: In patients with Bell’s palsy, fMRI may represent a useful tool to predict long-term
outcome, guide therapeutic approach, and monitor treatment response
Longitudinal study on low-dose aspirin versus placebo administration in silent brain infarcts: the silence study
Background. We investigated low-dose aspirin (ASA) efficacy and safety in subjects with silent brain infarcts (SBIs) in preventing new cerebrovascular (CVD) events as well as cognitive impairment. Methods. We included subjects aged ≥45 years, with at least one SBI and no previous CVD. Subjects were followed up to 4 years assessing CVD and SBI incidence as primary endpoint and as secondary endpoints: (a) cardiovascular and adverse events and (b) cognitive impairment. Results. Thirty-six subjects received ASA while 47 were untreated. Primary endpoint occurred in 9 controls (19.1%) versus 2 (5.6%) in the ASA group (p=0.10). Secondary endpoints did not differ in the two groups. Only baseline leukoaraiosis predicts primary [OR 5.4 (95%CI 1.3-22.9, p=0.022)] and secondary endpoint-A [3.2 (95%CI 1.1-9.6, p=0.040)] occurrence. Conclusions. These data show an increase of new CVD events in the untreated group. Despite the study limitations, SBI seems to be a negative prognostic factor and ASA preventive treatment might improve SBI prognosis. EU Clinical trial is registered with EudraCT Number: 2005-000996-16; Sponsor Protocol Number: 694/30.06.04
Evidence of impaired brain activity balance after passive sensorimotor stimulation in multiple sclerosis
Objectives
Examination of sensorimotor activation alone in multiple sclerosis (MS) patients may not yield a comprehensive view of cerebral response to task stimulation. Additional information may be obtained by examining the negative BOLD response (deactivation). Aim of this work was to characterize activation and deactivation patterns during passive hand movements in MS patients.
Methods
13 relapsing remitting-MS patients (RRMS), 18 secondary progressive-MS patients (SPMS) and 15 healthy controls (HC) underwent an fMRI study during passive right-hand movements. Activation and deactivation contrasts in the three groups were entered into ANOVA, age and gender corrected. Post-hoc analysis was performed with one-sample and two-sample t-tests. For each patient we obtained lesion volume (LV) from both T1- and T2-weighted images.
Results
Activations showed a progressive extension to the ipsilateral brain hemisphere according to the group and the clinical form (HC<RRMS<SPMS). Significant deactivation of the ipsilateral cortical sensorimotor areas was reduced in both patient groups with respect to HC. Deactivation of posterior cortical areas belonging to the default mode network (DMN), was increased in RRMS, but not in SPMS, with respect to HC. The amount of activation in the contralateral sensorimotor cortex was significantly correlated with that of deactivation in the DMN in HC and RRMS, but not in SPMS. Both increased activation and decreased deactivation patterns correlated with LV.
Conclusion
In RRMS patients, increased cortical activation was associated with increased deactivation of the posterior cortex suggesting a greater resting-state activity in the DMN, probably aimed at facilitating sensorimotor circuit engagement during task performance. In SPMS the coupling between increased sensorimotor activation/increased DMN deactivation was not observed suggesting disorganization between anticorrelated functional networks as a consequence of a higher level of disconnection
Letter: Thrombotic Neurovascular Disease in COVID-19 Patients.
Although the respiratory system is the primary target of the coronavirus, studies have demonstrated a strong tropism to the central nervous system (CNS).1,2 The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects cells by binding to the angiotensin-converting enzyme 2 (ACE2) receptor. This receptor is also found in the CNS and plays a crucial role in autoregulating cerebral perfusion pressure.3,4 Additionally, epidemiological data demonstrated increased mortality due to cardiovascular and cerebrovascular diseases during flu pandemics due to a hypercoagulable state.5,6 The triad of neuroinvasion of SARS-CoV-2, induction of hypercoagulable state,5-9 and the inhibition of ACE2 blocking the formation of Angiotensin (1-7) serve as the pathophysiology for neurovascular insults.3,4 We present a case series of coronavirus disease 2019 (COVID-19) patients from 2 health systems developing cerebrovascular insult
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