Cortical Brain Stimulation with Endovascular Electrodes.

Electrical stimulation of neural tissue and recording of neural activity are the bases of emerging prostheses and treatments for spinal cord injury, stroke, sensory deficits, and drug-resistant neurological disorders. Safety and efficacy are key aspects for the clinical acceptance of therapeutic neural stimulators. The cortical vasculature has been shown to be a safe site for implantation of electrodes for chronically recording neural activity, requiring no craniotomy to access high-bandwidth, intracranial EEG. This work presents the first characterization of endovascular cortical stimulation measured using cortical subdural surface recordings. Visual stimulation was used to verify electrode viability and cortical activation was compared with electrically evoked activity. Due to direct activation of the neural tissue, the latency of responses to electrical stimulation was shorter than for that of visual stimulation. We also found that the center of neural activation was different for visual and electrical stimulation indicating an ability of the stentrode to provide localized activation of neural tissue.

A bioinspired soft manipulator for minimally invasive surgery.

This paper introduces a novel, bioinspired manipulator for minimally invasive surgery (MIS). The manipulator is entirely composed of soft materials, and it has been designed to provide similar motion capabilities as the octopus's arm in order to reach the surgical target while exploiting its whole length to actively interact with the biological structures. The manipulator is composed of two identical modules (each of them can be controlled independently) with multi-directional bending and stiffening capabilities, like an octopus arm. In the authors' previous works, the design of the single module has been addressed. Here a two-module manipulator is presented, with the final aim of demonstrating the enhanced capabilities that such a structure can have in comparison with rigid surgical tools currently employed in MIS. The performances in terms of workspace, stiffening capabilities, and generated forces are characterized through experimental tests. The combination of stiffening capabilities and manipulation tasks is also addressed to confirm the manipulator potential employment in a real surgical scenario.

[The reliability of different groups of sample teeth in assessing the status of periodontal disease in epidemiological studies]. / Attendibilità di diversi gruppi di denti campione nel valutare lo stato di malattia parodontale negli studi epidemiologici.

The possibility of evaluating periodontal disease status in a given population by examining a limited number of sample teeth is of undoubted value in epidemiological studies. To this end, a cross-section study was performed to assess whether the dental sample proposed by Ramfjord effectively reflects the entire dentition status in terms of the main Clinical Indices of Periodontal Disease, in particular pocket depth. In addition, two randomly selected samples of six teeth were also evaluated using the same criteria. On the basis of their findings, the Authors confirm the epidemiological validity of Ramfjord's dental sample and stress that different groups of sample teeth may be efficaciously used to assess the periodontal disease status of the entire dentition in epidemiological studies.