Objective: To describe hyperintense vessels sign (HVS) in patients with acute stroke on fluid-attenuated inversion recovery (FLAIR) MRI and determine its clinical significance and utility. Background: Enhancement of vessels on postcontrast MRI in patients with acute stroke is considered an indicator of early brain ischemia. Recently, the FLAIR technique has shown promise in earlier and better detection of ischemic brain parenchymal lesions. Methods: Two observers retrospectively reviewed 304 MRI of patients with stroke and identified 30 patients with acute middle cerebral artery stroke and HVS on FLAIR obtained within 24 hours of symptom onset. These patients were evaluated with contrast-enhanced MRI (n = 9), MR angiography of carotid and intracranial circulation (n = 30), cerebral angiography (n = 8), transcranial Doppler (n = 17), and SPECT (n = 16). The extent of HVS was compared with final infarct size and NIH Stroke Scale score. Results: HVS on FLAIR was seen in 10% of the patients with acute stroke. HVS was associated with large vessel occlusion or severe stenosis (>90%). Intravascular enhancement on contrast MRI was observed in vessels that were hyperintense on FLAIR. Both cortical and subcortical infarcts demonstrated HVS. MR angiographic and cerebral angiographic findings of large vessel occlusion or severe stenosis (>90%), slow flow, low velocities by transcranial Doppler, and hypoperfusion on SPECT correlated with HVS. HVS was the earliest ischemic change in three patients scanned within 3 hours of ictus. Final infarct size was smaller than the area showing HVS in all patients. Conclusion: HVS on FLAIR MRI is an indicator of slow flow and early ischemia as a result of large vessel occlusion or stenosis and inadequacy of collateral circulation. HVS does not mean that infarction has occurred but indicates brain tissue at risk of infarction. It should prompt consideration of revascularization and flow augmentation strategies.
Attention-deficit hyperactivity disorder (ADHD) is a neurological and neurodevelopmental childhood-onset disorder characterized by a persistent pattern of inattentiveness, impulsiveness, restlessness, and hyperactivity. These symptoms may continue in 55–66% of cases from childhood into adulthood. Even though the precise etiology of ADHD is not fully understood, it is considered as a multifactorial and heterogeneous disorder with several contributing factors such as heritability, auxiliary to neurodevelopmental issues, severe brain injuries, neuroinflammation, consanguineous marriages, premature birth, and exposure to environmental toxins. Neuroimaging and neurodevelopmental assessments may help to explore the possible role of genetic variations on ADHD neuropsychobiology. Multiple genetic studies have observed a strong genetic association with various aspects of neuropsychobiological functions, including neural abnormalities and delayed neurodevelopment in ADHD. The advancement in neuroimaging and molecular genomics offers the opportunity to analyze the impact of genetic variations alongside its dysregulated pathways on structural and functional derived brain imaging phenotypes in various neurological and psychiatric disorders, including ADHD. Recently, neuroimaging genomic studies observed a significant association of brain imaging phenotypes with genetic susceptibility in ADHD. Integrating the neuroimaging-derived phenotypes with genomics deciphers various neurobiological pathways that can be leveraged for the development of novel clinical biomarkers, new treatment modalities as well as therapeutic interventions for ADHD patients. In this review, we discuss the neurobiology of ADHD with particular emphasis on structural and functional changes in the ADHD brain and their interactions with complex genomic variations utilizing imaging genetics methodologies. We also highlight the genetic variants supposedly allied with the development of ADHD and how these, in turn, may affect the brain circuit function and related behaviors. In addition to reviewing imaging genetic studies, we also examine the need for complementary approaches at various levels of biological complexity and emphasize the importance of combining and integrating results to explore biological pathways involved in ADHD disorder. These approaches include animal models, computational biology, bioinformatics analyses, and multimodal imaging genetics studies.
Objective: To assess the knowledge of stroke in the general public in the Gulf Cooperation Council (GCC) countries. Background: The Arabian Gulf is a rapidly developing part of the world with major changes in the lifestyle that can increase the risk of stroke. To design effective stroke treatment and prevention strategies, an assessment of the public knowledge of stroke is required. Methods: A cross-sectional community-based survey was conducted at primary health care centers (PHCs), in urban and semi-urban areas, of the GCC countries (Qatar, Saudi Arabia, Kuwait, Bahrain, the United Arab Emirates, Oman) on the level of stroke awareness in the general public. Health care workers completed 3,750 face-to-face interviews. Results: 1,089 (29.0%) were familiar with the term ‘stroke’, and 29.3% considered the age group 30–50 at the highest risk for stroke. The commonest risk factors identified were hypertension (23.1%) and smoking (27.3%). People who did not know the term stroke had a higher incidence of diabetes, hypertension, and had more than one risk factor (p < 0.05). The most frequently identified stroke symptoms were weakness (23%) and speech problems (21.7%). Of those who recognized stroke, blockage of blood vessels was identified as the commonest cause of stroke (22%) followed by tension/worrying (20%). Doctors and nurses were regarded as the best source of stroke information (70%). In the univariate comparison, younger age (p < 0.001), higher level of education (p < 0.001), and female gender (p = 0.008) better predicted stroke recognition. In a multivariate logistic regression analysis, the level of education, monthly income and smoking were independent variables predicting stroke knowledge. Conclusion: The majority of the patients had not even heard the term stroke. Stroke knowledge was poorest among the groups that were at the highest risk for stroke. Stroke education has to focus on the high-risk groups, particularly the younger population. The health care workers at the PHCs and hospitals will need instructions on providing stroke information to the public. The level of knowledge of stroke risk factors and symptoms emphasizes the need for stroke education efforts in the community.
No published epidemiologic data on multiple sclerosis (MS) in Qatar exist. Our objectives were to determine the prevalence, demographics and clinical characteristics of MS in the Middle Eastern country of Qatar. We analyzed data for Qatari MS patients fulfilling the McDonald diagnostic criteria. A total of 154 patients fulfilled the inclusion criteria. On 31 April 2010, the crude prevalence of MS in Qatar was 64.57 per 100,000 inhabitants (95% CI: 58.31-70.37). The female-to-male ratio was 1.33:1. A positive family history was found in 10.4% of included MS patients. We conclude that Qatar is now a medium-to-high risk area for MS, with some important differences in clinical characteristics as compared to other countries in the region.
Objective To determine if pneumatic sequential compression devices (SCDs) combined with subcutaneous heparin and antiembolic hose reduce the risk of deep vein thrombosis (DVT) and pulmonary embolism (PE) in stroke patients. Background DVTs and PEs are serious complications among hospitalized stroke patients. Subcutaneous heparin and SCDs have both been used to prevent DVT. It is not known if SCDs combined with subcutaneous heparin can improve the protection afforded by heparin alone. Methods The study group was comprised of nonhemorrhagic stroke patients admitted to the neurology service from October 1988 through June 1996. From October 1988 through April 1991 (233 patients), and during February 1993 (16 patients), patients received 5,000 U subcutaneous heparin twice daily and antiembolic hose. From June 1991 through January 1993 and from March 1993 through June 1996 (432 patients) all nonambulatory stroke patients had SCDs applied to both legs in addition to subcutaneous heparin and antiembolic hose. Results Twenty-three of 249 patients (9.2%; 21 of 233 and two of 16 patients) treated with heparin alone developed DVT and six patients (2.4%) developed PE (six of 233 and zero of 16). Half the PE cases (three of six) were fatal and all PEs were in patients with DVT. Eighty-three of the 249 patients were nonambulatory. Twenty-two of the 23 DVTs and all the PEs developed in nonambulatory patients. Only one DVT (0.23%) and no PEs occurred among the 432 patients (148 nonambulatory) treated with SCDs as well as heparin. The addition of SCDs resulted in more than a 40-fold reduction in the risk of DVT. Conclusions Nonambulatory stroke patients have an increased risk for DVT and PE. Adding SCDs to treatment with subcutaneous heparin and antiembolic hose reduced the risks of DVTs and PEs. SCDs should be considered for adjunctive DVT prophylaxis in nonambulatory stroke patients.
1 July 2017 in Investigative Ophthalmology & Visual Science
Purpose: To evaluate whether corneal confocal microscopy (CCM) detects axonal degeneration and whether this is associated with retinal nerve fiber degeneration and clinical disability in patients with multiple sclerosis (MS). Methods: Twenty-five patients with MS and 25 healthy control subjects underwent CCM, optical coherence tomography (OCT), and assessment of neurological disability using the expanded disability status scale (EDSS) and MS severity score (MSSS). Results: In patients with MS compared with controls, there was a significant reduction in corneal nerve fiber density (CNFD), branch density (CNBD), and length (CNFL). There was no significant difference in CCM parameters between patients with optic neuritis (MS-ON) and without (MS-NON), or between relapsing-remitting (RRMS) and secondary-progressive MS (SPMS). There was significant thinning of the retinal nerve fiber layer (RNFL) in the global, temporal, temporal superior, and temporal inferior quadrants, with no difference between MS-ON and MS-NON. Patients with SPMS compared with RRMS had a significantly lower global, temporal superior, temporal inferior, nasal, and nasal superior RNFL. The EDSS and MSSS correlated significantly with CNBD, nasal, nasal superior, and nasal inferior RNFL and with CNBD and nasal inferior RNFL, respectively. Conclusions: CCM and OCT detect significant corneal and retinal nerve degeneration which relates to the severity of neurological deficits in patients with mild MS.