Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Review
Transcranial Doppler and Transcranial Color Duplex in Defining Collateral Cerebral Blood Flow.
In an acute stroke setting, transcranial Doppler (TCD) and transcranial color-coded duplex (TCCD) have an important diagnostic utility in the monitoring of an arterial occlusion and microemboli detection. In addition, TCD has proven to be a very useful tool in the detection and progression of cerebral vasospasm in patients with subarachnoid hemorrhage. ⋯ It is a noninvasive technique and can be utilized repeatedly allowing for changes in the blood flow dynamics as treatment is delivered. In this review, we outlined the evolving role of TCD/TCCD in defining CF in patients with an acute ischemic stroke, predicting clinical outcome and monitoring the treatment's efficacy of the CF augmentation.
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Review
Emotional Processing in the First 2 Years of Life: A Review of Near-Infrared Spectroscopy Studies.
Emotional stimuli processing during childhood helps us to detect salient cues in our environment and prepares us for our social life. In early childhood, the emotional valences of auditory and visual input are salient and relevant cues of social aspects of the environment, and it is of special interest to understand how exactly the processing of emotional stimuli develops. Near-infrared spectroscopy (NIRS) is a noninvasive neuroimaging tool that has proven valuable in studying emotional processing in children. ⋯ Our review provides an overview of the database on emotional processing in children up to 2 years of age. Furthermore, it demonstrates the need to include the less-studied age range of 1 to 2 years, and suggests the use of combined audio-visual stimuli and longitudinal studies for future research on emotional processing in children. Thus, NIRS might be a vital tool to study the associations between the early pattern of neural responses and socioemotional development later in life.
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Glossopharyngeal neuralgia causes extreme paroxysmal pain in the posterior pharynx, tonsillar region, base of tongue, or deep ear, that is, the distribution of the glossopharyngeal nerve. Some cases of glossopharyngeal neuralgia are associated with neurovascular conflict, usually by the posterior inferior cerebellar artery. Such symptomatic compression occurs only in proximal, centrally myelinated portions of the glossopharyngeal nerve near the brainstem. Microvascular decompression provides effective and durable pain relief for properly selected patients with medically refractory glossopharyngeal neuralgia. The purpose of this study is to describe a tailored MRI evaluation of neurovascular conflict in glossopharyngeal neuralgia to improve candidate selection for microvascular decompression. ⋯ A tailored glossopharyngeal neuralgia imaging evaluation protocol is presented. We believe this approach has helped improve microvascular decompression outcomes and reduce unnecessary procedures at our institution. Further research may elucidate whether clinical and imaging features, including neurovascular conflict severity, predict surgical outcome for glossopharyngeal neuralgia.
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Neuroinflammation has been implicated in the pathophysiology of Parkinson's disease (PD), which might be influenced by successful neuroprotective drugs. The uptake of [11 C](R)-PK11195 (PK) is often considered to be a proxy for neuroinflammation, and can be quantified using the Logan graphical method with an image-derived blood input function, or the Logan reference tissue model using automated reference region extraction. The purposes of this study were (1) to assess whether these noninvasive image analysis methods can discriminate between patients with PD and healthy volunteers (HVs), and (2) to establish the effect size that would be required to distinguish true drug-induced changes from system variance in longitudinal trials. ⋯ Although not necessarily reflecting absolute values, these noninvasive image analysis methods can discriminate between PD patients and HVs. We see a difference of 24% in the substantia nigra between PD and HV with a repeatability coefficient of 13%, showing that it will be possible to estimate responses in longitudinal, within subject trials of novel neuroprotective drugs.
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Comparative Study
Comparative Analysis of Markers of Mass Effect after Ischemic Stroke.
Midline shift determined on magnetic resonance imaging (MRI) or computed tomography (CT) images is a well-validated marker of mass effect after large hemispheric infarction and associated with mortality. In this study, we targeted a population with moderately sized strokes. We compared midline shift to other imaging markers and determined their ability to predict long-term outcome. ⋯ The ratio of ipsilateral to contralateral hemisphere volume, baseline lesion volume and lesional swelling volume best predicted poor outcome across a spectrum of stroke sizes.