Modulation of motor responses and neural activities with transcranial ultrasound stimulation based on closed-loop control / 生物医学工程学杂志

Closed-loop transcranial ultrasound stimulation technology is based on real-time feedback signals, and has the potential for precise regulation of neural activity. In this paper, firstly the local field potential (LFP) and electromyogram (EMG) signals of mice under different intensities of ultrasound stimulation were recorded, then the mathematical model of ultrasound intensity and mouse LFP peak/EMG mean was established offline based on the data, and the closed-loop control system of LFP peak and EMG mean based on PID neural network control algorithm was simulated and built to realize closed-loop control of LFP peak and EMG mean of mice. In addition, using the generalized minimum variance control algorithm, the closed-loop control of theta oscillation power was realized. There was no significant difference between the LFP peak, EMG mean and theta power under closed-loop ultrasound control and the given value, indicating a significant control effect on the LFP peak, EMG mean and theta power of mice. Transcranial ultrasound stimulation based on closed-loop control algorithms provides a direct tool for precise modulation of electrophysiological signals in mice.

Transcranial Ultrasound in Evaluation of Hypoxic-Ischemic Encephalopathy and Bleed in Preterm Neonates

Aims and Objectives: The aim of the study was to study ultrasound feature of hypoxic-ischemic encephalopathy (HIE) andintracranial hemorrhage.Materials and Methods: It was a non-interventional prospective cross-sectional observational study done over a period of1.5 years in the Department of Radiodiagnosis of Seth Gordhandas Sunderdas Medical College and King Edward MemorialHospital.Results: A total of 66 cases were evaluated during the study. There were a total of 36 male (54.5%) and 30 female (45.5%)neonates. The difference between a number of males and females was not found to be statistically significant. About 69.7% ofthe neonates were in the category of very low birth weight (LBW), which was significantly higher than that of LBW (P < 0001).In cases of intracranial bleed, the sensitivity and specificity of transcranial ultrasound were found to be 88.89% and 95.83%,respectively, with a diagnostic accuracy of 93.94%. The mean gestational age in patients with intracranial bleed was 29.83± 2.20 weeks. Early gestational age was significantly associated with intracranial bleed in neonates. In cases of HIE, thesensitivity and specificity of transcranial ultrasound were 83.33% and 92.59%, respectively, with a diagnostic accuracy of90.91%. Prevalence of preeclampsia in the mother was highest among the preterm neonates, which suggest that preeclampsiais a significant risk factor for prematurity. The proportion of cases that had vaginal delivery was significantly higher than that ofthose born through lower segment cesarean section (LSCS) in preterm neonates. The neonatal risk factors that were found tobe significantly associated with intracranial bleed and hypoxic encephalopathy were LBW, prematurity, and Apgar score is <6at 1 min and 5 min after birth. Preeclampsia and intrauterine growth restriction were found to be important maternal risk factorsfor intracranial bleed in preterm neonates. Preeclampsia and LSCS as the mode of delivery were observed to be importantmaternal risk factors for HIE in preterm neonates.Conclusion: Although the sensitivity and specificity of transcranial ultrasonography (USG) are less than that of magneticresonance imaging, (which is the gold standard in detecting HIE and intracranial bleed in preterm neonates) considering itssensitivity and specificity it can be still considered as the first-line imaging modality of choice for screening preterm neonatesfor HIE and intracranial bleed. Transcranial ultrasound can, therefore, be used as a routine screening imaging modality forpreterm neonates born before 37 weeks of gestational age. The ideal timing for first transcranial USG is on day 3 of life.Follow-up scans should be done on days 7, 14, and 30 to detect persistently abnormal periventricular echogenicity, and cysticchanges in HIE. In intracranial bleed follow-up, scans are needed to detect the resolution or progression of hemorrhage andventricular enlargement.

Correlación de la desviación de la línea media por ultrasonido transcraneal y tomografía axial computarizada / Correlation of average line division by transcraneal ultrasound and computerized axial tomography / Correlação do desvio da linha média por ultrassom transcraniano e tomografia axial computadorizada

Resumen: Introducción: La ultrasonografía realizada por especialistas no radiólogos es una herramienta que contribuye al diagnóstico y monitoreo de los pacientes neurocríticos, además es económica, precisa, no invasiva y puede efectuarse a la cabecera del paciente, considerando que la gran mayoría de los pacientes neurocríticos se encuentran en inestabilidad hemodinámica. El ultrasonido se define como una serie de ondas mecánicas, generalmente longitudinales, originadas por la vibración de un cuerpo elástico (cristal piezoeléctrico) y propagadas por un medio material (tejidos corporales), cuya frecuencia supera a la del sonido audible por el humano: 20,000 ciclos/segundo o 20 kilohercios (20 KHz). Algunos de los parámetros que se utilizan a menudo en ultrasonido son: frecuencia, velocidad de propagación, interacción del ultrasonido con los tejidos, ángulo de incidencia, atenuación y frecuencia de repetición de pulsos. Objetivo: Correlacionar la medición de la desviación de la línea media cerebral por ultrasonido (USG), con el «estándar de oro¼, la tomografía axial computarizada (TAC). Material y métodos: Se realizó un estudio observacional, prospectivo, longitudinal, comparativo y analítico. Se obtuvo la medición en 22 pacientes de la desviación de la línea media cerebral por TAC y USG con diferentes patologías neurológicas. Resultados: Se obtuvo una medición media de 6.81 mm de desviación de la línea media cerebral de pacientes a quienes se les midió por técnica de ultrasonido y una media de 6.63 mm de pacientes medidos por tomografía axial computarizada de cráneo. Se correlacionó por Pearson, obteniendo una correlación de 0.774 (95% IC), lo cual es significativo. Discusión: Se propone la medición de la desviación de la línea media cerebral por ultrasonido transcraneal como método rápido a la cabecera del paciente, la cual genera bajos costos y puede sustituir la falta de tomografía. Puede incluirse como una medida rápida para decidir manejo quirúrgico si existiese efecto de masa, cráneo hipertensivo o focalización neurológica cuando no se cuente con tomografía. La implicación contraria a esta acepción es que el personal debe tener entrenamiento previo para realizar ultrasonido transcraneal, ya que es «operador¼ dependiente. Conclusión: La medición de la línea media por ultrasonido y tomografía de cráneo se correlacionan de forma significativa, por lo que el uso de ultrasonido transcraneal puede ser un instrumento de valoración en caso de no contar con tomógrafo, aunque se requieren estudios más amplios para ser concluyentes.

Abstract: Background: Ultrasonography performed by non-radiological specialists is a tool that contributes to the diagnosis and monitoring of neurocritical patients, as well as being an economic, precise, non-invasive tool that can be performed at the head of the patient, considering that the vast majority of neurocritical patients are in hemodynamic instability. Ultrasound is defined as a series of mechanical waves, usually longitudinal, originated by the vibration of an elastic body (piezoelectric crystal) and propagated by a material medium (body tissues), whose frequency exceeds that of the audible sound by the human: 20,000 cycles/second or 20 kilohertz (20 KHz). Some of the parameters that are often used in ultrasound are: frequency, velocity of propagation, interaction of ultrasound with tissues, angle of incidence, attenuation and frequency of repetition of pulses. Objective: To correlate, the measurement of the deviation of the cerebral midline by ultrasound (USG), with the «standard gold¼, computed axial tomography (CT). Material and methods: An observational, prospective, longitudinal, comparative, analytical study was performed. The measurement was obtained in 22 patients of the mean deviation of the cerebral line by CAT and USG with different neurological pathologies. Results: A mean of 6.81 mm of mean deviation of the cerebral midline was obtained for patients who were measured by ultrasound technique and mean of 6.63 mm for patients measured by computerized axial computed tomography. It was correlated by Pearson obtaining a correlation of 0.774 (95% CI) which is significant. Discussion: We propose the measurement of the deviation of the cerebral midline by transcranial ultrasound as a rapid method, at the head of the patient, which generates few costs and can replace the lack of a CT. It can be included as a quick measure to decide on surgical management if there is mass effect, hypertensive skull or neurological targeting and we do not have available tomography. The implication contrary to this meaning is that there must be a previous training of the personnel for the realization of transcranial ultrasound since it is a «dependent¼ operator. Conclusion: The measurement of the midline by ultrasound and cranial tomography are significantly correlated, so the use of transcranial ultrasound can be an instrument of assessment in case of not having a tomograph, although a larger number is required of studies to be conclusive.

Resumo: Introdução: A ultrassonografia realizada por especialistas que não são radiologistas é uma ferramenta que contribui para o diagnóstico e acompanhamento de pacientes neurocríticos, além de ser uma ferramenta não invasiva, de baixo custo e precisa, que pode ser realizada à beira do leito, considerando que a grande maioria de pacientes neurocríticos estão em instabilidade hemodinâmica. O ultra-som é definido como uma série de ondas mecânicas, geralmente longitudinais, originadas pela vibração de um corpo elástico (cristal piezoelétrico) e propagadas por um meio material (tecidos corporais), cuja frequência excede a do som audível pelo humano: 20.000 ciclos/segundo ou 20 quilohertz (20 KHz). Alguns dos parâmetros mais utilizados na ultrassonografia são: freqüência, velocidade de propagação, interação do ultrassom com os tecidos, ângulo de incidência, atenuação e frequência de repetição de pulsos. Objetivo: Correlacionar a medida do desvio da linha média cerebral por ultrassonografia (USG) com o «padrão ouro¼, a tomografia axial computadorizada (TAC). Material e métodos: Realizou-se um estudo observacional, prospectivo, longitudinal, comparativo, analítico. A medida foi obtida em 22 pacientes com o desvio médio da linha cerebral por TAC e USG com diferentes patologias neurológicas. Resultados: Obteve-se uma medida média de 6.81 mm de desvio da linha média cerebral, para pacientes que foram medidos pela técnica de Ultrassonografia e média de 6.63 mm para pacientes medidos por Tomografia Axial Computadorizada de crânio. Foi correlacionado por Pearson obtendo uma correlação de 0.774 (IC 95%) que é significativa. Discussão: Propomos a medida do desvio da linha média cerebral pela ultra-sonografia transcraniana como método rápido, à beira do leito, o que gera poucos custos e pode substituir a falta de uma tomografia. Ele pode ser incluído como uma medida rápida para decidir o tratamento cirúrgico se houver um efeito de massa, um crânio hipertensivo ou uma focalização neurológica e não tivermos disponibilidade de tomografia. A implicação contrária a esse significado é que deve haver um treinamento prévio do pessoal para o ultrassom transcraniano, uma vez que ele é dependente do «operador¼. Conclusões: A mensuração da linha média pela ultrassonografia e pela tomografia craniana são significativamente correlacionadas, de modo que o uso da ultrassonografia transcraniana pode ser uma ferramenta de valoração no caso de não possuir um tomógrafo, embora seja necessário um número maior de estudos para ser conclusivo.

Effect of transcranial ultrasound stimulation on transcranial magneto-acoustic stimulation / 医疗卫生装备

Objective To explore the effect of the transcranial ultrasound stimulation(TUS)on transcranial magneto-acoustic stimulation(TMAS).Methods The healthy mice and Parkinson's disease(PD)mice were contrastively stimulated by TMAS and TUS.A TMAS group,a TUS group and a control group were established,and then the behavior and the electrophysiology results were analyzed and compared in the three groups. Results Both the chronic TMAS treatment and TUS treatment improved the motor ability and learning ability of the healthy mice and the PD mice. In addition, the TMAS-group mice showed better performances than the TUS-group mice and the ones in the control group.Conclusion TMAS has its effects promoted by TUS and mechanism explained in detail,which is actually a combined stimulation of coupling electric field and ultrasonic field.[Chinese Medical Equipment Journal,2018,39(5):17-21,49]

Effects of Transcranial Ultrasound Therapy on Balance and Walking in Children with Dyskinetic Cerebral Palsy / 中国康复理论与实践

Objective To observe the effects of transcranial ultrasound (TU) therapy on balance function and walking ability in children with dyskinetic cerebral palsy (CP). Methods From June, 2015 to February, 2016, 51 children with dyskinetic CP were randomly divided in-to control group (n=25) and TU group (n=26). All the children accepted routine rehabilitation, while TU group accepted TU in addition, 1.2 W/cm2 for 20 minutes per day, 5 times a week, for three weeks. They were evaluated with Pediatric Balance Scale (PBS), walking speed, step length and step width with footprint analysis before and after intervention. Results The PBS score, step length and walking speed im-proved in both groups after intervention (Z>4.112, t>3.338, P2.038, P<0.05). Conclusion TU therapy can improve balance function and walking ability in children with dyskinetic CP.

Utilidad del ultrasonido transcraneal en Neurología y Neuropsiquiatría

Entre los sistemas dopaminérgicos que se modifican durante la evolución humana y que, en ciertas condiciones de conectividad y neurotransmisión anormal, desencadenan cambios patológicos en la adolescencia y adultez, se encuentra el mesolímbico basal. En adultos el ultrasonido transcraneal se realiza por la escama del hueso temporal con un equipamiento con transductor sectorial y focal de 1,8 a 2,8 MHz. Los puntos de evaluación ecográficos fundamentales son el mesencéfalo, el área de la sustancia negra, el rafe, el cuerpo estriado y los tálamos, el tercer ventrículo y los sectores orbitofrontales. A pesar del acceso anatómico limitado, es uno de los métodos de Neuroimágenes que cuantifica la ecogenicidad (de 0 a 3) y el área de sección de la sustancia negra (normal hasta 0,2 cm² ), lo cual se correlaciona con el empeoramiento de los síntomas motores parkinsonianos. Además, se evalúa y mensura el rafe (normal: 1 mm), que se correlaciona con el humor o la apatía según corresponda. Los otros hallazgos evaluables son los cambios en el espesor del tegmentum mesenfálico (ángulo interpeduncular menor o mayor de 60º), el aumento de la ecogenicidad de los tálamos y los cuerpos estriados, y la dilatación del tercer ventrículo (mayor de 5 mm). Su presencia colabora en el diagnóstico, clasificación, tratamiento y seguimiento de distintas patologías, como enfermedad de Parkinson, parálisis supranuclear progresiva, distonías, degeneración córtico-basal, esquizofrenia, depresiones, trastorno bipolar y autismo.

The basal mesolimbic system is among the dopaminergic systems that undergo changes during human evolution and that, under certain conditions, connectivity and abnormal neurotransmission trigger pathological changes during adolescence and adulthood. Transcranial ultrasound in adults is performed through the temporal squama with equipment that has a focal sectorial transducer from 1.8 to 2.8 MHz. The key points of the ultrasound evaluation are mesencephalon, substantia nigra area, raphe, striatum and thalamus, third ventricle, and orbitofrontal sectors. Despite its limited anatomical access, it is one of the neuroimaging methods that quantifies the echogenicity (0-3) and the sectional area of the substantia nigra (normal up to 0.2 cm²), which correlates with the worsening of Parkinsonian motor symptoms. It also evaluates and measures the raphe (normal 1 mm) which correlates with humour or apathy. Thickness changes of the mesencephalic tegmentum (interpeduncular angle, smaller or greater than 60º), thalamus and striatum increased echogenicity, and the third ventricle dilation (greater than 5 mm), are other possible findings. These are used to corroborate the diagnosis, classification, treatment and monitoring of different pathologies, like Parkinson's disease, supranuclear progressive palsy, dystonias, cortico-basal degeneration, schizophrenia, depression, bipolar disorder, and autism.

Observation on effects of transcranial ultrasound to arterial recanalization in acute ischemic stroke patients / 中国医学装备

Objective:To investigate the clinical effects of transcranial ultrasound to arterial recanalization in acute ischemic stroke patients.Methods: Eighty cases of patients with acute ischemic stroke from February 2010 to May 2013 in our hospital were chosen as the experimental objects, and were divided into experimental group and control group randomly. The control group were treated with urokinase and transcranial ultrasound, the experimental group were treated with urokinase and placebo. The clinical effects of each group were compared.Results: The experimental group in the 2h and 24h when the recanalization rate was obviously higher than the control group, and the difference is statistically significant(x2=8.916,x2=8.155,P<0.05). Symptoms improved rate of patients in the 2h and 24h in the experimental group was obviously higher than that of the control group, and the difference was statistically significant. The experimental group prognostic good rate was 56.09%, while the control group was 23.08%, the difference was statistically significant(x2=9.081,P<0.05). The two groups had no statistically significant difference in mortality(x2=0.005,P<0.05). Conclusion: Patients with acute ischemic stroke with transcranial ultrasound treatment can significantly improve the prognosis of the patients condition, improve the rate of recanalization.

Transcranial ultrasound can improve sensory functioning in children with cerebral palsy / 中华物理医学与康复杂志

Objective To explore the effects of transcranial ultrasound (TU) on the sensory functioning of children with cerebral palsy (CP).Methods Sixty-seven children with CP were randomly divided into a TU group (n =33) and a control group (n =34).All of the children were given conventional rehabilitative treatment, but the children in the TU group also received TU stimulation at 1.2 W/cm2 for 20 min daily, 5 times a week.All the treatments continued for 3 weeks in both groups.Before and after the intervention, the latencies and amplitudes of N20 and P37 were recorded and the escape reflex threshold was measured using the Von-Frey method.Results Before the treatment there were no significant differences between the two groups.After the 3 weeks of treatment, significant differences were observed in the N20 and P37 amplitudes, but not in the latencies in the control group.In TU group, however, the N20 and P37 latencies were significantly shorter and the amplitudes were significantly improved after the treatment.So significant inter-group differences were found in terms of N20 latency and both N20 and P37 amplitude after the treatment.The average escape reflex threshold in the TU group was significantly lower than before treatment, but not significantly different from the control group's average.Conclusions Transcranial ultrasound can effectively shorten the latencies and increase the amplitudes of somatosensory evoked potentials, suggesting that it can improve somatosensory functioning in children with CP.

El ultrasonido con dispositivos portátiles es útil para el diagnóstico del ictus agudo / Portable ultrasound equipment of use in diagnosing acute ictus

La ecografía Doppler transcraneal (EDTC) y el dúplex carotídeo (DC) pueden realizarse mediante dispositivos portátiles, lo que permite su utilización junto a la cama del paciente en el Servicio de Urgencias y en la sala de neuro intervencionismo. Ambas técnicas permiten el diagnóstico del estado del árbol vascular cerebral y facilitan un diagnóstico rápido y una decisión terapéutica adecuada. Existe una creciente utilización del dúplex transcraneal (DuTC), que nos permite, además, la valoración del parénquima cerebral, lo que es especialmente útil en la monitorización de la evolución de las hemorragias cerebrales, el efecto masa intracraneal y la hidrocefalia. Finalmente, la EDTC tiene un efecto terapéutico, ya que potencia la recanalización con activador tisular del plasminógeno (tPA). La EDTC, el DuTC y el DC son herramientas diagnósticas excelentes que deberían utilizarse en la evaluación inmediata de todos los pacientes con ictus isquémico o hemorrágico agudo.

Transcranial Doppler (TCD) and carotid duplex (CD) can be used as portable tests, thus allowing for bedside use in the Emergency Service and Neurointerventional Room. Both tests broaden the abilities of the stroke neurologist to rapidly evaluate the vascular tree, facilitating a rapid diagnosis and appro-priate therapeutic decisions. There is a growing use of transcranial duplex (TCDu), which also allows assessment of the brain parenchyma, which is especially useful in monitoring the evolution of brain hemorrhage, intracranial mass effect and hydrocephalus. Finally, the TCD has a therapeutic effect be-cause it enhances arterial recanalization after tPA administration. The TCD, TCDu and CD are excellent diagnostic tools that should be used in all patients with ischemic or hemorrhagic stroke.

The contribution of transcranial ultrasound to arterial recanalization in acute ischemic stroke patients / 中华物理医学与康复杂志

Objective To study the effect of transcranial ultrasound (US) on arterial recanalization in acute ischemic stroke patients.Methods Patients with acute middle cerebral artery (MCA) main stem occlusion after 6 h were randomized into a target group receiving low-frequency,pulse-wave mode,transcranial US for 30 min or a control group.All were treated with intravenous urokinase for thrombolysis.Transcranial doppler sonography (TCD) was used to document vascular occlusion and confirm recanalization at 2 h and 24 h after treatment,and the patients were evaluated using the National Institutes of Health Stroke Scale ( NIHSS).Results Recanilization (complete or partial) after 2 hours was significantly higher in the US group (44.4％) compared with the control group ( 10.5％ ).Recanalization had occurred in 50％ of the US group 24 hours after treatment compared with 15.7％ of the controls.At 2 h after treatment,33.3％ of the US group and 5.5％ of the controls had improved at least 4 points on the NIHSS assessment.After 24 hours the figures were 44.4％ and 10.5％.After 3 months,11 subjects from US group (61.1％ ) had a modified Rankin score ≤2 compared with 4 subjects (21％) from the control group.Conclusions In acute ischemic stroke,transcranial US has positive effects on recanalization and neural function.