Deep brain stimulation effect in genetic dyskinetic cerebral palsy: The case of ADCY5- related disease

BACKGROUND

Cerebral Palsy (CP) represents a frequent cause of disability in childhood. Early in life, genetic disorders may present with motor dysfunction and diagnosed as CP. Establishing the primary, genetic etiology allows more accurate prognosis, genetic counselling, and planning for symptomatic interventions in homogeneous etiological groups. Deep brain stimulation (DBS) is recommended in refractory movement disorders, including isolated pediatric dystonias. For dystonia evolving in more complex associations in genetic CP, the effect of DBS is still understudied and currently only sporadically described.

OBJECTIVES

To report the effect of DBS applied to the globus pallidus pars interna (GPi) in children with complex movement disorders caused by pathogenic ADCY5 variants, diagnosed as dyskinetic CP previous to genetic diagnostic.

METHODS

We conducted a retrospective study on evolution of treatment with DBS in ADCY5-related disease. A standardized proforma including the different type of movement disorders and associated neurological signs was completed at each follow-up time, based on video recordings, as well as functional assessments used in children with CP.

RESULTS

Four children (mean of age, 13 ± 2.9 years) received GPi-DBS. The same de novo pathogenic missense variant (c.1252C > T, p.R418W) was identified in three out of four and a splice site variant (c.2088 + 2G > T) in one subject. Developmental delay and overlapping features including axial hypotonia, chorea, dystonic attacks, myoclonus, and cranial dyskinesia were present. The median age at DBS was 9 years and follow-up with DBS, 2.6 years. We identified a pattern of clinical response with early suppression of dystonic attacks, followed by improvement of myoclonus and facial dyskinesia. Effect on chorea was delayed and more limited. Two patients gained notable functional benefit related to sitting, standing, gait, use of upper limbs and speech.

CONCLUSION

ADCY5-related disease may benefit from GPi-DBS. The most significant clinical response relates to the early and sustained benefit on dystonic attacks and a variable but still positive response on the other hyperkinetic features. Genetic etiology of CP will contribute to further elucidate genotype-phenotype correlations and to refine DBS indication as network-related symptomatic interventions.

Localised impedance monitoring device for the remote clinical assessment of home-based dialysis patients

BioImpedance Spectroscopy (BIS) has been clinically used to determine the hydrational status of patients undergoing haemodialysis (HD). In the present project we are developing a calf-localised, integrated impedimetric device to periodically and conveniently measure and transmit information on the hydrational status of home-based patients to a remote clinic. Surprisingly, we have found that simple postural changes before or during measurement lead to significant fluid shifts in the lower leg that are as important and as long lasting as the effects of haemodialysis. These must be taken into account if potentially hazardous errors are not to be made in assessing a patient's hydrational status.

Effect of compression stockings on cutaneous microcirculation: Evaluation based on measurements of the skin thermal conductivity

Objective

To study of the microcirculatory effects of elastic compression stockings.

Materials and methods

In phlebology, laser Doppler techniques (flux or imaging) are widely used to investigate cutaneous microcirculation. It is a method used to explore microcirculation by detecting blood flow in skin capillaries. Flux and imaging instruments evaluate, non-invasively in real-time, the perfusion of cutaneous micro vessels. Such tools, well known by the vascular community, are not really suitable to our protocol which requires evaluation through the elastic compression stockings fabric. Therefore, we involve another instrument, called the Hematron (developed by Insa-Lyon, Biomedical Sensor Group, Nanotechnologies Institute of Lyon), to investigate the relationship between skin microcirculatory activities and external compression provided by elastic compression stockings. The Hematron measurement principle is based on the monitoring of the skin’s thermal conductivity. This clinical study examined a group of 30 female subjects, aged 42 years ±2 years, who suffer from minor symptoms of chronic venous disease, classified as C0s, and C1s (CEAP).

Results

The resulting figures show, subsequent to the pressure exerted by elastic compression stockings, an improvement of microcirculatory activities observed in 83% of the subjects, and a decreased effect was detected in the remaining 17%. Among the total population, the global average increase of the skin’s microcirculatory activities is evaluated at 7.63% ± 1.80% ( p < 0.0001).

Conclusion

The results from this study show that the pressure effects of elastic compression stockings has a direct influence on the skin’s microcirculation within this female sample group having minor chronic venous insufficiency signs. Further investigations are required for a deeper understanding of the elastic compression stockings effects on the microcirculatory activity in venous diseases at other stages of pathology.

A portable heat flux sensor

Nowadays monitoring physiological signals in real situations is essential to get the best diagnosis on patients. In this study we focus on the heat flux generated by the human body. We are developing a portable heat flux sensor using specific thermal materials.

Wearable sensor systems: the challenges

Given the soaring costs associated with the treatment of ever more prevalent chronic disease, it is widely agreed that a revolution is required in health care provision. It is often thought that the necessary technology already exists for the home-based monitoring of such patients and that it is other factors which are holding back the more widespread clinical uptake of these new tools. The authors suggest that the necessary sensor-related technologies are often not as advanced as may first appear; certainly they are generally not adequate for the robust, long-term monitoring of patients under real-life conditions. An additional problem is the evident efforts to apply a given sensor and related technology platform to any and all monitoring scenarios without sufficient consideration of patient needs and the clinical requirements. The authors review the key sensing platforms and suggest the applications for which they are best suited.

Thermal parameters measurement on fire fighter: improvement of the monitoring system

Real time monitoring of the thermal parameters on firefighter when operating is one of the ProeTEX project goals. The newly developed equipments in the framework of this project, integrate one temperature sensor and one heat flux sensor in the rescuer's outer garment. The environment in which firefighters operate is dangerous and the thermal risks can occur everywhere. Consequently the heat flux is so not necessarily symmetrical. To improve the thermally at risk situation detection, a modified platinum sensors array was integrated in the jacket in order to monitor simultaneously heat flux and temperature surrounding the rescuer. The sensors were placed in the most exposed area (shoulders and chest) to monitor thermal parameter in different directions. The heat flux is calculated from the temperature difference. This sensors array enables the detection of temperature increases and heat flux even when the heat source is localized on one side.

Thermal parameters measurement on fire fighter during intense fire exposition

To improve rescuer safety, coordination and efficiency, the European program ProeTEX aims at developing new equipment for the intervention staff. This equipment is based on micro and nanotechnologies and consisted of smart textile integrated sensor to monitor physiological parameters, environment of the rescuer but also acquisition module and communication module. Thermal parameters are of primer interest. Internal temperature, external temperature and heat flux are relevant parameters to prevent heat stroke in fire fighter when exposed to intense fire. These parameters are recorded during fire exposition and highlight, on one hand, that the outer garment of fire fighters' equipment insulates the fire fighter from the external environment, and on the other hand, that the thermal monitoring is relevant.

An integrated platform to assess driver's physiological and functional states

Physiological signals like Heart Rate, Respiration and Skin Resistance are relevant indicators to evaluate driver's mental state. Therefore, most methods based on physiological signals measurements have been improved on driving simulators or in experimental laboratories under carefully controlled conditions and rigorous protocols. To study driver's behavior in actual conditions, we have developed an in-vehicle system which could record contextual driving information, drivers' actions and physiological signals related to them. Recordings from the driver and the vehicle may give valuable information for a close estimation of driver's functional state, its evolution across time and thus a better understanding of driver's behavior. This system provides specific patterns related to the driver's functional state, according to the driving context. This paper is aimed to present the design and implementation of this system, well adapted to ergonomics.

A non invasive wearable sensor for the measurement of brain temperature

As the thermoregulation centres are deep in the brain, the cerebral temperature is one of the most important markers of fever, circadian rhythms physical and mental activities. However due to a lack of accessibility, the brain temperature is not easily measured. The axillary, buccal, tympanic and rectal temperatures do not reflect exactly the cerebral temperature. Nevertheless the rectal temperature is used as probably the most reliable indicator of the core body temperature. The brain temperature can be measured using NMR spectroscopy, microwave radiometry, near infrared spectroscopy, ultra-sound thermometry. However none of those methods are amenable to long term ambulatory use outside of the laboratory or of the hospital during normal daily activities, sport, etc. The brain core temperature "BCT" sensor, developed by the Biomedical Microsensors dpt of LPM at INSA-Lyon is a flexible active sensor using "zero-heat-flow" principle. The sensor has been used for experimental measurement: brain temperature during mental activity, and in hospital for the study of circadian rhythms. The results are in agreement with the measurement by the rectal probe. There are 2 versions of this sensor: a non ambulatory for the use in hospitals, and an ambulatory version using teletransmission. We are working for improving the autonomy of the ambulatory version up to several days. This wearable biomedical sensor (WBS) can be used for circadian assessment for chronobiology studies and in medical therapies.

New methodology for preventing pressure ulcers using actimetry and autonomous nervous system recording

Pressure ulcers constitute an important health problem. They affect lots of people with mobility disorder and they are difficult to detect and prevent because the damage begins on the muscle. This paper proposes a new approach to study pressure ulcers. We aim at developing a methodology to analyse the probability for a patient to develop a pressure ulcer, and that can detect risky situation. The idea is to relate the mobility disorder to autonomic nervous system (ANS) trouble. More precisely, the evaluation of the consequence of the discomfort on the ANS (stress induced by discomfort) can be relevant for the early detection of the pressure ulcer. Mobility is evaluated through movement measurement. This evaluation, at the interface between soft living tissues and any support has to consider the specificity of the human environment. Soft living tissues have non-linear mechanical properties making conventional rigid sensors non suitable for interface parameters measurement. A new actimeter system has been designed in order to study movements of the human body whatever its support while seating. The device is based on elementary active cells. The number of pressure cells can be easily adapted to the application. The spatial resolution is about 4 cm(2). In this paper, we compare activity measurement of a seated subject with his autonomic nervous system activity, recorded by E.motion device. It has been developed in order to record six parameters: skin potential, skin resistance, skin temperature, skin blood rate, instantaneous cardiac frequency and instantaneous respiratory frequency. The design, instrumentation, and first results are presented.

Interface pressure monitoring for a secured instrumented childbirth

Complications in forceps deliveries are rare but their consequences might be dramatics. This situation could be avoided if the obstetrician knows the information concerning symmetry of the obstetrical forceps position on the fetal head and the related interface pressure. Indeed, forceps delivery is an emergency gesture which is normally not expected. Our purpose is to determinate relevant parameters for a fast decision-making without any danger for the fetus. We have developed a new interface pressure measurement system in order to study pressure distribution of human body whatever its support (forceps, chair, bed...). This method has been adapted to measure the interface pressure between the fetal head and the forceps. This new system also provides information of forceps position symmetries. The aims of this system are: first, to prevent instrumented delivery accidents. Secondly, to provide a safe training of forceps technique. This paper presents results about experiments performed on phantoms of fetal head. Different forceps positions on phantom have been tested according to the classification of forceps application as per A.C.O.G 1981 (revised in 1991). These experiments have lead to the definition of relevant parameters in order to help the physician to validate the forceps positions before extraction.

Wrist ambulatory monitoring system and smart glove for real time emotional, sensorial and physiological analysis

Improvement of the quality and efficiency of the quality of health in medicine, at home and in hospital becomes more and more important Designed to be user-friendly, smart clothes and gloves fit well for such a citizen use and health monitoring. Analysis of the autonomic nervous system using non-invasive sensors provides information for the emotional, sensorial, cognitive and physiological analysis. MARSIAN (modular autonomous recorder system for the measurement of autonomic nervous system) is a wrist ambulatory monitoring and recording system with a smart glove with sensors for the detection of the activity of the autonomic nervous system. It is composed of a "smart tee shirt", a "smart glove", a wrist device and PC which records data. The smart glove is one of the key point of MARSIAN. Complex movements, complex geometry, sensation make smart glove designing a challenge. MARSIAN has a large field of applications and researches (vigilance, behaviour, sensorial analysis, thermal environment for human, cognition science, sport, etc...) in various fields like neurophysiology, affective computing and health monitoring.

FOR SAFE: instrumented and secured obstetrical forceps

Operative vaginal deliveries represent a significant amount of vaginal deliveries. Operative delivery involves either forceps either vacuum extraction. Complications are frequent but rarely severe (cutaneaous lesions, facial palsy...). However, it is essential to limit these complications by helping the obstetrician to position his extraction instrument. It is the aim of the FOR SAFE device: provide a new instrumented forceps which performs the interface pressure measurement between the fetal head and the shanks of the forceps. Interface pressure evaluation requires interaction between the living tissue and the sensor, just like a man needs to touch an object with its fingertip to evaluate its compliance. The design of the sensor is "bio inspired". The sensor interacts with the matter, without modifying phenomenon to be measured.

Which techniques to improve the early detection and prevention of pressure ulcers?

Pressure ulcers are a serious health problem for people with mobility disorders, like elders in acute care, long-term care, and home care settings. It also concerns paraplegics, tetraplegics or persons with burned injuries. Pressure ulcers result in significant morbidity and mortality. Consequences are a high human suffering, with high cost in terms of treatment. Several risk factors have been identified for the development of pressure ulcers: they are classified into extrinsic and intrinsic factors. Extrinsic factors include interface pressure, shear forces, friction. Intrinsic factors are the nutritional state of the patient, its age, diseases. There is little information about the mechanism of the formation of pressure sores but it is agreed that it is a complex process. The difficulty of the prevention lies in the evaluation of these factors. It is an essential stage to optimize the preventative measures. Actually, no quantifiable parameters exist to predict the formation of a pressure ulcer. This article is aimed to propose new techniques developed for the early detection of pressure ulcers. First, extrinsic parameters as the interface pressure and its consequences on the mobility are investigated. A new actimeter is presented to monitor the movements of the patient. The second part is dedicated to the presentation of a new imaging technique which can help the physician to control tissue elasticity of the patient. The technique is called elastography, it is a 3D strain estimation of soft biological tissues. Finally, the last way of investigation is the combination of extrinsic and intrinsic factors evaluation for a most relevant earlier diagnosis. Before the description of these techniques, it is essential to understand the phenomenology associated to the development of pressure sores. Only in this way, new techniques can be developed.

New concepts and technologies in home care and ambulatory monitoring

The world is becoming more and more health conscious. Society, health policy and patients' needs are all changing dramatically. The challenges society is currently facing are related to the increase in the aging population, changes in lifestyle, the need for healthcare cost containment and the need for improvement and monitoring of healthcare quality. The emphasis is put on prevention rather than on treatment. In addition, patients and health consumers are waiting for non-invasive or minimally-invasive diagnosis and treatment methods, for home care, short stays in hospital, enhancement of rehabilitation, information and involvement in their own treatment. Progress in science and technology offers, today, miniaturization, speed, intelligence, sophistication and new materials at lower cost. In this new landscape, microtechnologies, information technologies and telecommunications are key factors. Telemedicine has also evolved. Used initially to exchange patients' files, radiographic data and other information between health providers, today telemedicine contributes to new trends in "hospital extension" through all-day monitoring of vital signs, professional activities, entertainment and home-based activities. The new possibilities for home care and ambulatory monitoring are provided at 4 levels: a) Microsensors. Microtechnologies offer the possibility of small size, but also of intelligent, active devices, working with low energy, wireless and non-invasive or minimally-invasive; b) Wrist devices are particularly user friendly and combine sensors, circuits, supply, display and wireless transmission in a single box, very convenient for common physical activities; c) Health smart clothes make contact with 90 % of the skin and offer many possibilities for the location of sensors. These sensors have to be thin, flexible and compatible with textiles, or made using textile technologies, such as new fibers with specific (mechanical, electrical and optical) properties; d) Health smart homes. The aim of this method is to improve the patient's living conditions and to avoid the cost of long hospitalization. "Exosensors" are used for measurement of the activity and behavior of the patient. The field of applications is very large, e.g. continuous monitoring of elderly populations, professional and military activities, athletes performance and condition, and people with disabilities. This new healthcare approach has to take into account lifestyle for improving prevention. For the patient to be more and more involved in his/her own therapy, new responsibilities and ethics have to be defined. A "societal health education" has to be provided to physicians and to patients to get all the benefits of this new context.