Objectives: Preclinical studies found that epidural motor cortex stimulation improved motor deficits after stroke, but a phase III trial in humans did not corroborate these results. The current retrospective analysis examined subjects randomized to stimulation in order to identify features distinguishing responders from nonresponders.Methods: Anatomic (MRI measures of gray matter thickness and of white matter tract injury) and physiologic methods (motor evoked responses) were examined as predictors of treatment response.Results: Among 60 subjects randomized to cortical stimulation, both anatomic and physiologic measures at baseline predicted behavioral response to therapy. Anatomically, those achieving the primary efficacy endpoint had a smaller fraction of the corticospinal tract injured by stroke compared to those who did not (44% vs 72%, p Ͻ 0.04), and rarely had severe tract injury. Physiologically, the primary efficacy endpoint was reached more often (67%) by those with preserved motor evoked responses (MER) upon cortical stimulation compared to those lacking MER (27%, p Ͻ 0.05). Those with an elicitable MER also had a lower rate of precentral gyrus injury (0% vs 33%, p Ͻ 0.05) by stroke, as compared to those lacking MER, and had higher gray matter volume compared to those lacking MER in regions including ipsilesional precentral gyrus. Conclusions:In this clinical stroke trial, the more that the physiologic integrity of the motor system was preserved, the more likely that a patient was to derive gains from subsequent therapy, consistent with preclinical models. Functional and structural preservation of key brain substrates are important to deriving gain from a restorative therapy. Neurology Stroke remains a major source of human disability. An emerging group of therapies aims to improve function in the chronic phase of stroke, when behavioral deficits are fixed.1 This is an issue of considerable impact, as at least 6.4 million such persons are alive in the United States alone.2 A major question is how to distinguish patients who are likely to respond to a restorative therapy from patients who are not.The current study considers this issue in relation to a phase III clinical trial 3,4 that examined behavioral effects of epidural cortical stimulation after stroke. Preclinical studies in rodents and in nonhuman primates suggested that this form of brain stimulation improved behavioral outcome.5-9 Together, these studies described a biological model whereby epidural motor cortex stimulation promotes motor cortex plasticity and, as a result, improves motor behavioral status.In the clinical trial, patients with chronic hemiparetic stroke underwent anatomic and physiologic assessment of the motor system and were then randomized to either epidural cortical stimulation plus physiotherapy or to no stimulation plus physiotherapy. The main study results were that the 2 treatment groups did not significantly differ in the proportion of subjects who From the

When healthy subjects undergo brain imaging, incidental findings are not rare. The optimal response to such findings has been the focus of considerable discussion. The current report describes the operations and results of a system that provides review of incidental findings by an appropriate medical professional. A web-based system was created whereby investigators performing brain MRI scans on healthy subjects could refer images with suspected concerns to a board certified radiologist who had a Certificate of Added Qualification in Neuroradiology. The specific details of this system are described. Among 27 scans suspected by an investigator of having a significant finding, all but one were referred by a researcher with a PhD. The most common concerns described by these investigators were for the possible presence of a cyst or of enlarged ventricles. The most common findings reported by the radiologist were Virchow-Robin spaces and cysts. Findings were generally of low clinical significance, with 1 major exception. Identifying the optimal response to incidental findings in neuroimaging research remains a challenge. The current report describes a system for providing expert assistance and so addresses these issues in the setting of suspected incidental findings. To our knowledge the current system is the first to provide a specific means for evaluation of incidental findings in neuroimaging research.

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