scholarly journals Effects of pulse parameters on the temperature distribution of a human head exposed to the electromagnetic pulse

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shan Wang ◽  
Zhongguo Song ◽  
Yanning Yuan ◽  
Guozhen Guo ◽  
Jianjun Kang

AbstractThe presence of blood–brain barrier (BBB) is a major obstacle to effectively deliver therapeutics to the central nervous system (CNS); hence, the outcomes following treatment of CNS diseases remain unsatisfactory. Fortunately, electromagnetic pulses (EMPs) provide a non-invasive method to locally open the BBB. To obtain the optimal pulse parameters of EMP-induced BBB opening to ensure the effective delivery of CNS drugs, it is particularly important to measure and assess the effects of pulse parameters on the temperature distribution in the human head exposed to EMPs. In this paper, the specific anthropomorphic mannequin phantom was adopted and the temperature increase in the human head induced by EMPs of different parameters was estimated in the software “COMSOL Multiphysics”. The results show that the temperature distribution profiles with different EMP parameters have almost similar characteristics, the highest temperature increase values in the human head are positively correlated with variations of EMP parameters, and potential hazards to the human head may occur when EMP parameters exceed the safety threshold, which will provide theoretical basis for seeking the optimal EMP parameters to open the BBB to the greatest extent within a safe range.

1970 ◽  
Vol 8 (2) ◽  
pp. 257-260 ◽  
Author(s):  
P Sharma ◽  
S Neupane ◽  
M Shrestha ◽  
R Dwivedi ◽  
K Paudel

Background: Cysticercosis in humans is infection with the larval form (cysticercus cellulosae) of the pork tapeworm T. solium. Encystment of larvae can occur in almost any tissue. The location of cysts in order of frequency is the central nervous system, subcutaneous tissue and striated muscle, vitreous humour of the eye and, rarely, other tissues. High resolution ultrasound can be used in the diagnosis of muscular and soft tissue cysticercosis. Objective: The aim of this study is to evaluate the ultrasonographic findings in cases of muscular and soft tissue cysticercosis. Materials and methods: It was a retrospective review of the cases of muscular and soft tissue cysticercosis which were diagnosed by ultrasound during June 2007 to May 2009 in the department of Radiology and Imaging, Nepalgunj Medical College Teaching Hospital. A total of six patients were evaluated. Result: There were four males and two females. Age of the patient ranged from 18 to 50 years. All of the patients presented with a swelling with pain in five of them. There was a wide variation in the location of the cysts. In all cases ultrasound revealed a cystic lesion with an echogenic eccentric pedunculated nodule attached to the wall. The mean diameter of the cyst was 6mm. Smooth wall was present in five cases whereas one of the cysts revealed irregular wall. Pericystic inflammatory changes were seen in the adjacent muscles. Conclusion: Ultrasound is a safe and non-invasive method that can be used in the diagnosis of muscular and soft tissue cysticercosis. Key words: Muscular and soft tissue cysticercosis; ultrasound. DOI: 10.3126/kumj.v8i2.3571 Kathmandu University Medical Journal (2010), Vol. 8, No. 2, Issue 30, 257-260


Author(s):  
Atulya. M. ◽  
Angel Alex ◽  
Jesil Mathew. A

The drug discovery and pharmacokinetic studies of drugs of the central nervous system depend on the successful collection of cerebrospinal fluid from lab animal models. Many a time, the treatment regime and management of diseases depends on the penetration and distribution of medicaments across the blood-brain barrier and for which a non-contaminated cerebrospinal fluid sample is essential. The present study was to simplify the cerebrospinal fluid collection from cisterna magna of rat, maximizing the quantity and minimizing the contamination. The rat is anaesthetized with Xylazine Ketamine combination intravenously and was kept on an inverted polypropylene tray with its head down at 45° angle. A depressible surface which look like a rhomb between occipital protuberances and the spine of the atlas becomes noticeable. A butterfly needle attached to a syringe was introduced into the cisterna magna, and cerebrospinal fluid is aspirated. The method is non-invasive and doesn’t require any sophisticated equipment and lessens the chance of contamination of the sample with blood. The technique is also less time consuming and easy to perform.


2012 ◽  
Vol 31 (04) ◽  
pp. 224-230 ◽  
Author(s):  
Leonardo Christian Welling ◽  
Eberval Gadelha Figueiredo ◽  
Fábio Santana Machado ◽  
Almir Ferreira Andrade ◽  
Vinicius Monteiro Guirado ◽  
...  

AbstractComputed tomography is essential in head injuried patients for the detection of structural damage to the brain. However, the ability of CT scanning to predict the presence or absence of intracranial hypertension has been debated in the literature. Since the optic nerve is part of the central nervous system and in case of raised pressure in the cerebrospinal fluid its sheath inflates. Based in this hypothesis the authors reviewed the role of the optic nerve sheat diameter in diagnosis intracranial hypertension after traumatic brain injury. This non-invasive method is useful to predict the risk of intracranial hypertension and select patients to ICP monitoring, especially in those with normal CT scans.


Author(s):  
Calligari Dalila ◽  
Corvaglia Martina ◽  
Stringile Michela ◽  
Colombo Giovanni ◽  
Assirelli Angela

The introduction of velocity-sensitive sequences, such as those based on the phase-contrast technique, has recently established a lure for the evaluation of the dynamics of CSF in MRI because it is the only non-invasive method for the study of the CSF flow. These sequences add to the classic anatomical study of brain, a qualitative functional analysis of his cerebrospinal fluid system studied with sequences acquired in the sagittal plane, maintaining high spatial and temporal resolution despite the small size of the analyzed section and the low speed of the circulating liquor. The aim of this paper is to illustrate the importance of using amplitude and phase (Phase Contrast) images in Cine-RM, in healthy subjects and in patients with intra-cranial and cervical district diseases.


2001 ◽  
Vol 12 (1) ◽  
pp. 8-14
Author(s):  
Gertraud Teuchert-Noodt ◽  
Ralf R. Dawirs

Abstract: Neuroplasticity research in connection with mental disorders has recently bridged the gap between basic neurobiology and applied neuropsychology. A non-invasive method in the gerbil (Meriones unguiculus) - the restricted versus enriched breading and the systemically applied single methamphetamine dose - offers an experimental approach to investigate psychoses. Acts of intervening affirm an activity dependent malfunctional reorganization in the prefrontal cortex and in the hippocampal dentate gyrus and reveal the dopamine position as being critical for the disruption of interactions between the areas concerned. From the extent of plasticity effects the probability and risk of psycho-cognitive development may be derived. Advance may be expected from insights into regulatory mechanisms of neurogenesis in the hippocampal dentate gyrus which is obviously to meet the necessary requirements to promote psycho-cognitive functions/malfunctions via the limbo-prefrontal circuit.


Author(s):  
Patrick Veit-Haibach ◽  
Martin W. Huellner ◽  
Martin Banyai ◽  
Sebastian Mafeld ◽  
Johannes Heverhagen ◽  
...  

Abstract Objectives The purpose of this study was the assessment of volumetric CT perfusion (CTP) of the lower leg musculature in patients with symptomatic peripheral arterial disease (PAD) before and after interventional revascularisation. Methods Twenty-nine consecutive patients with symptomatic PAD of the lower extremities requiring interventional revascularisation were assessed prospectively. All patients underwent a CTP scan of the lower leg, and hemodynamic and angiographic assessment, before and after intervention. Ankle-brachial pressure index (ABI) was determined. CTP parameters were calculated with a perfusion software, acting on a no outflow assumption. A sequential two-compartment model was used. Differences in CTP parameters were assessed with non-parametric tests. Results The cohort consisted of 24 subjects with an occlusion, and five with a high-grade stenosis. The mean blood flow before/after (BFpre and BFpost, respectively) was 7.42 ± 2.66 and 10.95 ± 6.64 ml/100 ml*min−1. The mean blood volume before/after (BVpre and BVpost, respectively) was 0.71 ± 0.35 and 1.25 ± 1.07 ml/100 ml. BFpost and BVpost were significantly higher than BFpre and BVpre in the treated limb (p = 0.003 and 0.02, respectively), but not in the untreated limb (p = 0.641 and 0.719, respectively). Conclusions CTP seems feasible for assessing hemodynamic differences in calf muscles before and after revascularisation in patients with symptomatic PAD. We could show that CTP parameters BF and BV are significantly increased after revascularisation of the symptomatic limb. In the future, this quantitative method might serve as a non-invasive method for surveillance and therapy control of patients with peripheral arterial disease. Key Points • CTP imaging of the lower limb in patients with symptomatic PAD seems feasible for assessing hemodynamic differences before and after revascularisation in PAD patients. • This quantitative method might serve as a non-invasive method, for surveillance and therapy control of patients with PAD.


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