Japanese Regulatory Considerations for Interoperability of Medical Devices.

With the rapid technological innovations of the Internet of Things (IoT), the situation surrounding medical devices and medical systems has been changing. Interoperable medical devices-medical devices capable of interoperating in a clinically significant way with other medical devices-have been developed, and interoperable medical systems consisting of two or more interconnected interoperable medical devices are being used in clinical settings. However, general points that need to be considered to ensure safe and effective interoperability have yet to be fully established in Japan.

Rotors anchored by refractory islands drive torsades de pointes in an experimental model of electrical storm.

Background: Electrical storm (ES) is a life-threatening emergency in patients at high risk of ventricular tachycardia/ventricular fibrillation (VF), but the pathophysiology and molecular basis are poorly understood.

Objective: The purpose of this study was to explore the electrophysiological substrate for experimental ES.

Methods: A model was created by inducing chronic complete atrioventricular block in defibrillator-implanted rabbits, which recapitulates QT prolongation, torsades des pointes (TdP), and VF episodes.

Quantitative analysis of the anatomical changes in the scalp and hair follicles in androgenetic alopecia using magnetic resonance imaging.

Background: Although the structural changes of the scalp in androgenetic alopecia (AGA) have been reported, these changes have been poorly understood. It is expected that modern MRI would visualize the scalp anatomy in vivo. This study aimed to explore whether AGA causes (a) changes in the thickness of the scalp, (b) anatomical changes in the hair follicles, and (c) changes in the signal intensity of MRI.

MR Imaging of Hair and Scalp for the Evaluation of Androgenetic Alopecia.

Purpose: Although androgenetic alopecia (AGA) is a common cause of hair loss, little is known regarding the magnetic resonance imaging (MRI) of the AGA or scalp. This study aimed to analyze whether MRI for hair and scalp (MRH) can evaluate anatomical changes in the scalp caused by AGA.

Methods: Twenty-seven volunteers were graded for the severity of AGA using the Hamilton-Norwood Scale (HNS), commonly used classification system.

Interaction of phase singularities on the spiral wave tail: reconsideration of capturing the excitable gap.

The action mechanism of stimulation toward spiral waves (SWs) owing to the complex excitation patterns that occur just after point stimulation has not yet been experimentally clarified. This study sought to test our hypothesis that the effect of capturing excitable gap of SWs by stimulation can also be explained as the interaction of original phase singularity (PS) and PSs induced by the stimulation on the wave tail (WT) of the original SW. Phase variance analysis was used to quantitatively analyze the postshock PS trajectories.

Mechanism of Traumatic Brain Injury at Distant Locations After Exposure to Blast Waves: Preliminary Results from Animal and Phantom Experiments.

Purpose Primary blast-induced traumatic brain injury (bTBI) is the least understood of the four phases of blast injury. Distant injury induced by the blast wave, on the opposite side from the wave entry, is not well understood. This study investigated the mechanism of distant injury in bTBI.

Detection Algorithm of Phase Singularity Using Phase Variance Analysis for Epicardial Optical Mapping Data.

Objective: Spiral reentry is a recognized cause of tachycardia. Detection and tracking of the spiral core are essential for understanding the spiral wave dynamics. The core of the spiral corresponds to a phase singularity (PS), which can be identified in an optical mapping image by a kernel convolution method.

Pulsed Laser-induced Liquid Jet System for Treatment of Sellar and Parasellar Tumors: Safety Evaluation.

Objective: The pulsed laser-induced liquid jet (LILJ) system is an emerging surgical instrument intended to assist both maximal removal of the lesion and functional maintenance through preservation of fine vessels and minimal damage to the surrounding tissue. The system ejects the minimum required amount of pulsed water through a handy bayonet-shaped catheter. We have already shown a significant increase in removal rate, in addition to a noteworthy reduction of intraoperative blood loss and procedure time in the treatment of large pituitary and skull base tumors in a single-institution series.

Hypothermia in victims of the great East Japan earthquake: a survey in Miyagi prefecture.

Objective: A survey was conducted to describe the characteristics of patients treated for hypothermia after the Great East Japan Earthquake.

Methods: Written questionnaires were distributed to 72 emergency medical hospitals in Miyagi Prefecture. Data were requested regarding inpatients with a temperature less than 36ºC admitted within 72 hours after the earthquake.

Reliability of telecommunications systems following a major disaster: survey of secondary and tertiary emergency institutions in Miyagi Prefecture during the acute phase of the 2011 Great East Japan Earthquake.

Introduction: Telecommunication systems are important for sharing information among health institutions to successfully provide medical response following disasters.

Hypothesis/problem: The aim of this study was to clarify the problems associated with telecommunication systems in the acute phase of the Great East Japan Earthquake (March 11, 2011).

Methods: All 72 of the secondary and tertiary emergency hospitals in Miyagi Prefecture were surveyed to evaluate the telecommunication systems in use during the 2011 Great Japan Earthquake, including satellite mobile phones, multi-channel access (MCA) wireless systems, mobile phones, Personal Handy-phone Systems (PHS), fixed-line phones, and the Internet.

Tissue dissection before direct manipulation to the pathology with pulsed laser-induced liquid jet system in skull base surgery--preservation of fine vessels and maintained optic nerve function.

Background: Most difficulties in skull base tumor removal are generally caused by adhesion of feeding arteries to the vital structures and cranial nerves. Water jet technology provides tissue dissectability with preservation of fine blood vessels both in experimental and clinical situations. However problems still remain regarding whether tumor removal with preservation of peripheral nerve function is possible or not.

Single camera system for multi-wavelength fluorescent imaging in the heart.

Optical mapping has been a powerful method to measure the cardiac electrophysiological phenomenon such as membrane potential(V(m)), intracellular calcium(Ca(2+)), and the other electrophysiological parameters. To measure two parameters simultaneously, the dual mapping system using two cameras is often used. However, the method to measure more than three parameters does not exist.

Clinical implications of intraoperative infrared brain surface monitoring during superficial temporal artery-middle cerebral artery anastomosis in patients with moyamoya disease.

Object: Surgical revascularization for moyamoya disease prevents cerebral ischemic attacks by improving cerebral blood flow (CBF). Symptomatic cerebral hyperperfusion is a potential complication of this procedure, but its treatment is contradictory to that for ischemia. Because intraoperative techniques to detect hyperperfusion are still lacking, the authors performed intraoperative infrared monitoring in moyamoya disease using a novel infrared imaging system.

Intraoperative infrared brain surface blood flow monitoring during superficial temporal artery-middle cerebral artery anastomosis in patients with childhood moyamoya disease.

Objective: To monitor patency of the bypass and to accomplish comprehensive visualized evaluation of brain surface hemodynamics in childhood moyamoya patients, we performed intraoperative monitoring using novel infrared imaging system.

Materials And Methods: Intraoperative monitoring of brain surface blood flow by IRIS V infrared imaging system has been conducted during superficial temporal artery-middle cerebral artery anastomosis on seven sides of five pediatric patients with moyamoya disease (man/woman = 2:3, 7-8 years old). The range of recipient artery was 0.

Intraoperative infrared brain surface blood flow monitoring during superficial temporal artery-middle cerebral artery anastomosis in a patient with moyamoya disease: clinical implication of the gradation value in postoperative clinical course--a case report.

Background: Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis is a safe and effective treatment for moyamoya disease. Symptomatic cerebral hyperperfusion is a potential complication of this procedure, especially in adult cases. Accurate diagnosis of postoperative hyperperfusion is important because its treatment is contradictory to that for ischemia.

Development of optical mapping system with real-time feedback stimulation in the heart.

Recent studies showed that electrical stimuli in the excitable gaps during ventricular fibrillation (VF) are important for defibrillation requiring low electrical energy. We developed an optical mapping system that measures action potentials and controls the timings and sites of electrical stimulus to verify the effectiveness of electrical stimulation in the excitable gaps. In this paper, the time delay of feedback algorithms with our optical mapping system was evaluated and the feedback stimulation protocols were operated using isolated rabbit hearts.