scholarly journals In vivo Visualization of Pig Vagus Nerve “Vagotopy” Using Ultrasound

2021 ◽  
Vol 15 ◽  
Author(s):  
Megan L. Settell ◽  
Aaron C. Skubal ◽  
Rex C. H. Chen ◽  
Maïsha Kasole ◽  
Bruce E. Knudsen ◽  
...  

Background: Placement of the clinical vagus nerve stimulating cuff is a standard surgical procedure based on anatomical landmarks, with limited patient specificity in terms of fascicular organization or vagal anatomy. As such, the therapeutic effects are generally limited by unwanted side effects of neck muscle contractions, demonstrated by previous studies to result from stimulation of (1) motor fibers near the cuff in the superior laryngeal and (2) motor fibers within the cuff projecting to the recurrent laryngeal.Objective: Conventional non-invasive ultrasound, where the transducer is placed on the surface of the skin, has been previously used to visualize the vagus with respect to other landmarks such as the carotid and internal jugular vein. However, it lacks sufficient resolution to provide details about the vagus fascicular organization, or detail about smaller neural structures such as the recurrent and superior laryngeal branch responsible for therapy limiting side effects. Here, we characterize the use of ultrasound with the transducer placed in the surgical pocket to improve resolution without adding significant additional risk to the surgical procedure in the pig model.Methods: Ultrasound images were obtained from a point of known functional organization at the nodose ganglia to the point of placement of stimulating electrodes within the surgical window. Naïve volunteers with minimal training were then asked to use these ultrasound videos to trace afferent groupings of fascicles from the nodose to their location within the surgical window where a stimulating cuff would normally be placed. Volunteers were asked to select a location for epineural electrode placement away from the fascicles containing efferent motor nerves responsible for therapy limiting side effects. 2-D and 3-D reconstructions of the ultrasound were directly compared to post-mortem histology in the same animals.Results: High-resolution ultrasound from the surgical pocket enabled 2-D and 3-D reconstruction of the cervical vagus and surrounding structures that accurately depicted the functional vagotopy of the pig vagus nerve as confirmed via histology. Although resolution was not sufficient to match specific fascicles between ultrasound and histology 1 to 1, it was sufficient to trace fascicle groupings from a point of known functional organization at the nodose ganglia to their locations within the surgical window at stimulating electrode placement. Naïve volunteers were able place an electrode proximal to the sensory afferent grouping of fascicles and away from the motor nerve efferent grouping of fascicles in each subject (n = 3).Conclusion: The surgical pocket itself provides a unique opportunity to obtain higher resolution ultrasound images of neural targets responsible for intended therapeutic effect and limiting off-target effects. We demonstrate the increase in resolution is sufficient to aid patient-specific electrode placement to optimize outcomes. This simple technique could be easily adopted for multiple neuromodulation targets to better understand how patient specific anatomy impacts functional outcomes.

2020 ◽  
Author(s):  
Megan L. Settell ◽  
Maisha Kasole ◽  
Aaron C. Skubal ◽  
Bruce E. Knudsen ◽  
Evan N. Nicolai ◽  
...  

AbstractBackgroundPlacement of the clinical vagus nerve stimulating cuff is a standard surgical procedure based on anatomical landmarks, with limited patient specificity in terms of fascicular organization or vagal anatomy. As such, the therapeutic effects are generally limited by unwanted side effects of neck muscle contractions, demonstrated by previous studies to result from stimulation of 1) motor fibers near the cuff in the superior laryngeal and 2) motor fibers within the cuff projecting to the recurrent laryngeal.ObjectiveThe use of patient-specific visualization of vagus nerve fascicular organization could better inform clinical cuff placement and improve clinical outcomes.MethodsThe viability of ultrasound, with the transducer in the surgical pocket, to visualize vagus nerve fascicular organization (i.e. vagotopy) was characterized in a pig model. Ultrasound images were matched to post-mortem histology to confirm the utility of ultrasound in identifying fascicular organization.ResultsHigh-resolution ultrasound accurately depicted the vagotopy of the pig vagus nerve intra-operatively, as confirmed via histology. The stereotypical pseudo-unipolar cell body aggregation at the nodose ganglion was identifiable, and these sensory afferent fascicular bundles were traced down the length of the vagus nerve. Additionally, the superior and recurrent laryngeal nerves were identified via ultrasound.ConclusionsIntraoperative visualization of vagotopy and surrounding nerves using ultrasound is a novel approach to optimize stimulating cuff placement, avoid unwanted activation of motor nerve fibers implicated in off-target effects, and seed patient-specific models of vagal fiber activation to improve patient outcomes.


2016 ◽  
Vol 4 (1) ◽  
pp. 9 ◽  
Author(s):  
Aneta Tomescu ◽  
Rodica Sîrbu ◽  
Stelian Paris ◽  
Emin Cadar ◽  
Cristina Luiza Erimia ◽  
...  

Our study is a rewiew of Methotrexate therapy in obstetrica? diseases such us: hydatidiform mole, and medical abortion. In the medical world, methotrexate is a citostatic drug used in neoplastic diseases. The clinical pharmacology data regarding methotrexate is presented, alongside route of administration and therapeutic effects in malignant disease, hydatiform mole, and medical abortion. The use of methotrexate in medical abortion and ectopic pregnancy is a great accomplishment, as it replaces a surgical intervention marred by characteristic side effects, with similar results.


2016 ◽  
Vol 2 (1) ◽  
pp. 9 ◽  
Author(s):  
Aneta Tomescu ◽  
Rodica Sîrbu ◽  
Stelian Paris ◽  
Emin Cadar ◽  
Cristina Luiza Erimia ◽  
...  

Our study is a rewiew of Methotrexate therapy in obstetrica? diseases such us: hydatidiform mole, and medical abortion. In the medical world, methotrexate is a citostatic drug used in neoplastic diseases. The clinical pharmacology data regarding methotrexate is presented, alongside route of administration and therapeutic effects in malignant disease, hydatiform mole, and medical abortion. The use of methotrexate in medical abortion and ectopic pregnancy is a great accomplishment, as it replaces a surgical intervention marred by characteristic side effects, with similar results.


2015 ◽  
pp. 80-85
Author(s):  
Van Anh Nguyen ◽  
Van Nhan Le ◽  
Nguyen Nhu Phuong Phan

Objectives: To investigate and evaluate the therapeutic effects of Hoe hoa tan II in the treatment of internal haemorroids grade I, II and III. Ingredients of the remedy include: Hoe Hoa (Styphonolonium japonicum), Chi xac (Fructus citri Aurantii), Hau phac (Magnolia offinalis), Tran bi (Citrus deliciosa Tenore), Thuong thuat (Atractylodes lancea), O mai (Armeniaca vulgaris Lamk), Cam thao (Clycyrrhiza uralensis), Duong quy (Radix Angelicae Sinensis). Subjects and methods: Randomised controlled study (RCT) has been conducted on 60 patients which were divided into two groups, i.e. the first 30 patient group were treated with Hoe hoa tan II remedy 20 g, and the second 30 patient group were treated with Daflon 500 mg in the course of 14 days. Results: Study showed that Hoe hoa tan II has helped improve symptoms of internal haemorroids grade I, II and III such as bleeding, anal exudation, pain, reducing the size of the haemorroid tissues. The remedy has been shown to have the most significant effect on relieving constipation which is typical in haemorroids. The study also revealed no unwanted effects caused by this formula. Conclusion: Hoe hoa tan II can be therapeutically used to treat internal haemorroids grade I, II and III without causing any serious side effects. Key words: Hoe hoa tan II, internal haemorroids grade I, II, III.


2020 ◽  
Vol 6 (3) ◽  
pp. 284-287
Author(s):  
Jannis Hagenah ◽  
Mohamad Mehdi ◽  
Floris Ernst

AbstractAortic root aneurysm is treated by replacing the dilated root by a grafted prosthesis which mimics the native root morphology of the individual patient. The challenge in predicting the optimal prosthesis size rises from the highly patient-specific geometry as well as the absence of the original information on the healthy root. Therefore, the estimation is only possible based on the available pathological data. In this paper, we show that representation learning with Conditional Variational Autoencoders is capable of turning the distorted geometry of the aortic root into smoother shapes while the information on the individual anatomy is preserved. We evaluated this method using ultrasound images of the porcine aortic root alongside their labels. The observed results show highly realistic resemblance in shape and size to the ground truth images. Furthermore, the similarity index has noticeably improved compared to the pathological images. This provides a promising technique in planning individual aortic root replacement.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wan Fatin Amira Wan Mohd Zawawi ◽  
M. H. Hibma ◽  
M. I. Salim ◽  
K. Jemon

AbstractBreast cancer is the most common cancer that causes death in women. Conventional therapies, including surgery and chemotherapy, have different therapeutic effects and are commonly associated with risks and side effects. Near infrared radiation is a technique with few side effects that is used for local hyperthermia, typically as an adjuvant to other cancer therapies. The understanding of the use of near NIR as a monotherapy, and its effects on the immune cells activation and infiltration, are limited. In this study, we investigate the effects of HT treatment using NIR on tumor regression and on the immune cells and molecules in breast tumors. Results from this study demonstrated that local HT by NIR at 43 °C reduced tumor progression and significantly increased the median survival of tumor-bearing mice. Immunohistochemical analysis revealed a significant reduction in cells proliferation in treated tumor, which was accompanied by an abundance of heat shock protein 70 (Hsp70). Increased numbers of activated dendritic cells were observed in the draining lymph nodes of the mice, along with infiltration of T cells, NK cells and B cells into the tumor. In contrast, tumor-infiltrated regulatory T cells were largely diminished from the tumor. In addition, higher IFN-γ and IL-2 secretion was observed in tumor of treated mice. Overall, results from this present study extends the understanding of using local HT by NIR to stimulate a favourable immune response against breast cancer.


Author(s):  
Azin Ayatollahi ◽  
Alireza Firooz ◽  
Ensieh Lotfali ◽  
Faraz Mojab ◽  
Azam Fattahi

Introduction: Dandruff and seborrheic dermatitis [SD] are similar skin conditions but have different severities. Because the current therapies are not able to completely remove dandruff, herbal extracts with better effectiveness and fewer side effects are being used in the pharmaceutical and cosmetic industries. Due to the adverse effects of chemical drugs, the use of natural products and traditional medicine has sharply increased over the past few decades. Therefore, in this review, we report herbs used as anti-dandruff agents in traditional medicine around the world. Methods: The review was conducted on the literature available on the medicinal utility of certain plants as antidandruff agents using PubMed and Google Scholar and the following search terms: Dandruff and Plants or Medicinal Plant and Dandruff treatment; and Essential oil and Dandruff. Results: Because the current therapies are not able to completely remove dandruff, herbal extracts with better effectiveness and fewer side effects are being used in the pharmaceutical and cosmetic industries. Nowadays, there are many different types of herbal antidandruff shampoo. They are effective and safe without the side effects of chemical agents. Recently, a large number of physicians have turned to herbal medicine. Clinical evidence of the therapeutic effects from herbal products has led to the study of many more herbs for their therapeutic roles. Conclusion: Herbal are now accepted to act a essential role in the development of favourable therapeutics, either alone or in combination with conventional antibiotics. However, the major challenges to this include finding compounds with satisfactorily lower MICs, low toxicity, and high bioavailability for effective and safe use in humans and animals.


2016 ◽  
Vol 28 (6) ◽  
pp. 1051-1052
Author(s):  
Craig D'Cunha ◽  
Christos Plakiotis ◽  
Daniel W. O'Connor

Electroconvulsive therapy (ECT) prescription rates rise with age, making it important that treatments be made as effective and safe as possible (Plakiotis et al., 2012). Older people are vulnerable to post-treatment confusion and to subsequent deficits in attention, new learning, and autobiographical memory (Gardner and O'Connor, 2008). Strategies to minimize cognitive side-effects include unilateral electrode placement and stimulus dose titration whereby electrical charge is individually calibrated to seizure threshold (Sackeim et al., 2000). It remains the case, however, that threshold levels typically rise over the treatment course, leading to an increase both in delivered charge and the risk of adverse sequelae.


2007 ◽  
Vol 4 (3) ◽  
pp. 71-73
Author(s):  
Sahbal Aras ◽  
Semih Semin

Recently, the use of psychostimulant medication in children with symptoms of attention-deficit hyperactivity disorder (ADHD) has been subject to extensive debate. The problems faced while assessing and diagnosing ADHD, unnecessary prescribing of psychostimulants, the possible side-effects of psychostimulants on the developing brain, the risk of drug dependency, and the risk of stigmatising children through medicalisation of normal life events are considered among the principal objections to the use of psychostimulant medications. On the other hand, what also need to be taken into account are the increasing evidence on the genetic, biochemical and diagnostic validity of the disorder, the data showing the therapeutic effects of psychostimulants and the rarity of the above-mentioned side-effects, as well as the ethical problems created by insufficient treatment of children because of the concerns of parents. A critical evaluation of these conflicting opinions by mental health professionals might contribute to the application of ethical principles. While making this kind of evaluation, it is important to pay regard to the specific sociocultural features of the country, as well as the prevailing worldwide discussion.


BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Yi Cao ◽  
Suwan Pan ◽  
Mengying Yan ◽  
Chongyang Sun ◽  
Jianyu Huang ◽  
...  

Abstract Background Although electrical stimulation of the peripheral and central nervous systems has attracted much attention owing to its potential therapeutic effects on neuropsychiatric diseases, its non-cell-type-specific activation characteristics may hinder its wide clinical application. Unlike electrical methodologies, optogenetics has more recently been applied as a cell-specific approach for precise modulation of neural functions in vivo, for instance on the vagus nerve. The commonly used implantable optical waveguides are silica optical fibers, which for brain optogenetic stimulation (BOS) are usually fixed on the skull bone. However, due to the huge mismatch of mechanical properties between the stiff optical implants and deformable vagal tissues, vagus nerve optogenetic stimulation (VNOS) in free-behaving animals continues to be a great challenge. Results To resolve this issue, we developed a simplified method for the fabrication of flexible and stretchable polymer optical fibers (POFs), which show significantly improved characteristics for in vivo optogenetic applications, specifically a low Young’s modulus, high stretchability, improved biocompatibility, and long-term stability. We implanted the POFs into the primary motor cortex of C57 mice after the expression of CaMKIIα-ChR2-mCherry detected frequency-dependent neuronal activity and the behavioral changes during light delivery. The viability of POFs as implantable waveguides for VNOS was verified by the increased firing rate of the fast-spiking GABAergic interneurons recorded in the left vagus nerve of VGAT-ChR2 transgenic mice. Furthermore, VNOS was carried out in free-moving rodents via chronically implanted POFs, and an inhibitory influence on the cardiac system and an anxiolytic effect on behaviors was shown. Conclusion Our results demonstrate the feasibility and advantages of the use of POFs in chronic optogenetic modulations in both of the central and peripheral nervous systems, providing new information for the development of novel therapeutic strategies for the treatment of neuropsychiatric disorders.


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