Sparsity driven ultrasound imaging

An image formation framework for ultrasound imaging from synthetic transducer arrays based on sparsity-driven regularization functionals using single-frequency Fourier domain data is proposed. The framework involves the use of a physics-based forward model of the ultrasound observation process, the formulation of image formation as the solution of an associated optimization problem, and the solution of that problem through efficient numerical algorithms. The sparsity-driven, model-based approach estimates a complex-valued reflectivity field and preserves physical features in the scene while suppressing spurious artifacts. It also provides robust reconstructions in the case of sparse and reduced observation apertures. The effectiveness of the proposed imaging strategy is demonstrated using experimental data

Attention Deficit Hyperactivity Disorder

Objective: Attention deficit hyperactivity disorder (ADHD) and bipolar disorder are frequently comorbid diagnoses. Aim of this study was to compare the neurological soft signs in patients with bipolar disorder and in patients with comorbid ADHD to those in control subjects. This study helps us to understand the impact of ADHD on the soft neurological signs in bipolar disorder in adults.Methods: Sixty euthymic patients diagnosed with bipolar I disorder and 33 healthy control subjects were enrolled in the study. The Wender Utah Rating Scale, Adult ADHD Rating Scale and The Structured Clinical Interview for DSM-IV Disorders were administered to the participants. The subjects were classified into three study groups, namely, bipolar patients with comorbid ADHD (n=13), bipolar patients without comorbid ADHD (n=47) and controls. We performed the Neurological Evaluation Scale in the three groups.Results: Comorbid ADHD group showed poor performance on complex motor tasks such as fist-ring test and fist-edge-palm test, while bipolar group showed poor performance on Ozeretski test. Comorbid ADHD patients performed poorly on graphestesia, stereognosis and primitive reflexes.Conclusion: Abnormalities of repetitive motor performance and primitive reflexes observed in comorbid ADHD patients support the hypothesis that ADHD involves a deficit in fronto-striatal-thalamic neurocircuits. In contrast, impaired sequential motor performance in BP subjects shows deficits in dorsolateral prefrontal cortex. These results show that the pathophysiology of bipolar disorder and ADHD may be related to different areas, and comorbid ADHD may increase the severity of the soft neurological signs. (Archives of Neuropsychiatry 2011; 48: 107-13

Deficit Hyperactivity Disorder

Aim: The present study aimed to compare cognitive signs of bipolar disorder patients with that of adult attention-deficit/hyperactivity disorder (ADHD) patients.Method: The study comprised 66 bipolar disorder patients, 63 ADHD patients, and 58 healthy controls.Structured Clinical Interview for DSM-IV Axis-I Disorders (SCID-I), Wender Utah Rating Scale, and Adult Attention-Deficit/Hyperactivity Rating Scale were performed in all subjects, whereas bipolar disorder patients underwent additional Hamilton Depression Rating Scale and Young Mania Rating Scale. Subsequently, all participants underwent cognitive assessment including Digit Ordering Test, Verbal Memory Process Test, Wisconsin Card Sorting Test and Stroop Test.Results: Bipolar disorder, ADHD and control groups did not differ significantly from each other with regard to age, sex and duration of education. Bipolar patients displayed poorer performance in Digit Span Test, Verbal Memory Process Test, Wisconsin Card Sorting Test and Stroop Test as compared to the control group. ADHD patients were worse than the control subjects in Stroop Test (subtest of difference in times). Bipolar disorder patients were poorer than ADHD patients in cognitive tests except for Stroop Test.Conclusion: In general, bipolar disorder patients have much more severe cognitive impairment than ADHD patients in terms of verbal memory and executive functions. The results supports the idea of bipolar disorder and ADHD are different, at least in terms of cognitive performance