We recently demonstrated that ultra-high-speed real-time fMRI using multi-slab echo-volumar imaging (MEVI) significantly increases sensitivity for mapping task-related activation and resting-state networks (RSNs) compared to echo-planar imaging (Posse et al., 2012). In the present study we characterize the sensitivity of MEVI for mapping RSN connectivity dynamics, comparing independent component analysis (ICA) and a novel seed-based connectivity analysis (SBCA) that combines sliding-window correlation analysis with meta-statistics. This SBCA approach is shown to minimize the effects of confounds, such as movement, and CSF and white matter signal changes, and enables real-time monitoring of RSN dynamics at time scales of tens of seconds. We demonstrate highly sensitive mapping of eloquent cortex in the vicinity of brain tumors and arterio-venous malformations, and detection of abnormal resting-state connectivity in epilepsy. In patients with motor impairment, resting-state fMRI provided focal localization of sensorimotor cortex compared with more diffuse activation in task-based fMRI. The fast acquisition speed of MEVI enabled segregation of cardiac-related signal pulsation using ICA, which revealed distinct regional differences in pulsation amplitude and waveform, elevated signal pulsation in patients with arterio-venous malformations and a trend toward reduced pulsatility in gray matter of patients compared with healthy controls. Mapping cardiac pulsation in cortical gray matter may carry important functional information that distinguishes healthy from diseased tissue vasculature. This novel fMRI methodology is particularly promising for mapping eloquent cortex in patients with neurological disease, having variable degree of cooperation in task-based fMRI. In conclusion, ultra-high-real-time speed fMRI enhances the sensitivity of mapping the dynamics of resting-state connectivity and cerebro-vascular pulsatility for clinical and neuroscience research applications.

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Intractable hiccups are debilitating and usually a result of some underlying disease. Initial management includes vagal maneuvers and pharmacotherapy. When hiccups persist despite medical therapy, surgical intervention rarely is pursued. Cases described in the literature cite successful phrenic nerve blockade, crush injury, or percutaneous phrenic nerve pacing. The authors report on a case of intractable hiccups occurring after a posterior fossa stroke, Complete resolution of the spasms has been achieved to date following the placement of a vagus nerve stimulator.

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Summary: Purpose:To assess the effect of vagus nerve stimulation (VNS) on interictal epileptiform activity in the human hippocampus. Clinical studies have established the efficacy of vagus nerve stimulation in patients with epilepsy (VNS Study Group, 1995), although the electrophysiologic effects of VNS on the human hippocampus and mesial temporal lobe structures remain unknown.Methods: We report a case study in which a patient with an implanted VNS underwent intracranial electrode recording before temporal lobectomy for intractable complex partial seizures. Epileptiform spikes and sharp waves were recorded from a depth electrode placed in the patient's left hippocampus. Spike frequencies and sharp-wave frequencies before and during VNS were compared using both a 5-and a 30-Hz stimulus. Different stimulation rates were tested on different days, and all analyses were performed using a Student's t test.Results: We found no significant differences in spike frequency between baseline periods and stimulation at 5 and 30 Hz. In contrast, stimulation at 30 Hz produced a significant decrease in the occurrence of epileptiform sharp waves compared with the baseline, whereas stimulation at 5 Hz was associated with a significant increase in the occurrence of epileptiform sharp waves.Conclusions: VNS produces a measurable electrophysiologic effect on epileptiform activity in the human hippocampus. Although a clinical response to VNS did not occur in our patient before surgery, 30-Hz VNS suppressed interictal epileptiform sharp waves that were similar in appearance to those seen during the patient's actual seizures. In contrast, 5-Hz stimulation appeared to increase the appearance of interictal sharp waves. Key Words: Vagus nerve stimulationHippocampal depth electrodes-Epileptiform activitySpikes-Sharp waves.Vagus nerve stimulation (VNS) using the NeuroCybernetic Prosthesis (NCP; Cyberonics, Inc., Houston, TX, U.S.A.) was approved by the Food and Drug Administration (FDA) in July 1997 for use as an adjunctive therapy for adults or adolescents older than 12 years with medically refractory partial onset seizures. Although its efficacy is well established (1,2), the exact mechanism of action of VNS remains unknown. Animal studies have shown that stimulation of the cervical portion of the vagus nerve can terminate electrographic seizures caused by either topical cortical or systemic strychnine or pentylenetetrazol (PTZ) (3). VNS can also block the development of kindled seizures (4).McLachlan (5) found that electrical stimulation of the left vagus nerve reduced or abolished penicillin-induced interictal cortical spikes in Wistar rats during and immediately after stimulation. In his study, stimulation consisted of square-wave pulses of 0.01-1.2 mA at 20 or 50 Hz. Woodbury and Woodbury (6) studied the effects of different stimulus parameters and found that stimulation of unmyelinated (C) vagus nerve fibers in male SpragueDawley rats could inhibit electrically or chemically induced seizures. They concluded that the optimal stimulus ...