-
Journal of Neurosurgery Aug 2019Surgical treatments for moyamoya disease (MMD) include direct revascularization procedures with proven efficacy, for example, superficial temporal artery (STA) to middle...
Surgical treatments for moyamoya disease (MMD) include direct revascularization procedures with proven efficacy, for example, superficial temporal artery (STA) to middle cerebral artery (MCA) bypass, STA to anterior cerebral artery bypass, occipital artery (OA) to MCA bypass, or OA to posterior cerebral artery bypass. In cases with poor development of the parietal branch of the STA, the posterior auricular artery (PAA) is often developed and can be used as the bypass donor artery. In this report, the authors describe double direct bypass performed using only the PAA as the donor in the initial surgery for MMD.In the authors' institution, MMD is routinely treated with an STA-MCA double bypass. Some patients, however, have poor STA development, and in these cases the PAA is used as the donor artery. The authors report the use of the PAA in the treatment of 4 MMD patients at their institution from 2013 to 2016. In all 4 cases, a double direct bypass was performed, with transposition of the PAA as the donor artery. Good patency was confirmed in all cases via intraoperative indocyanine green angiography and postoperative MRA or cerebral angiography. The mean blood flow measurement during surgery was 58 ml/min. No patients suffered a stroke after revascularization surgery.
PubMed: 31443070
DOI: 10.3171/2019.5.JNS19173 -
The Laryngoscope Mar 2020Primary tracheal resection in appropriately selected patients with tracheal stenosis achieves >90% success rate. Risk factors for complications have been identified,...
OBJECTIVES/HYPOTHESIS
Primary tracheal resection in appropriately selected patients with tracheal stenosis achieves >90% success rate. Risk factors for complications have been identified, making some patients high risk for this procedure. Herein is a review and discussion of a novel treatment method for tracheal stenosis utilizing a prefabricated composite auricular cartilage graft embedded in a supraclavicular artery island flap (pSCAIF) for tracheal reconstruction in high-risk patients.
STUDY DESIGN
Retrospective case series.
METHODS
After institutional review board approval, cases were analyzed after data collection. Between 2014 and 2016, eight patients underwent airway reconstruction using an auricular cartilage graft prefabricated within a supraclavicular artery island flap reconstruction; all of these were included in the study. Each case was reviewed, and relevant details of patient and disease characteristics, operative course, postoperative course, decannulation, and status at last follow-up were isolated and reported.
RESULTS
Seven of eight patients were female. The most common cause of stenosis was iatrogenically induced multilevel stenosis (7/8 patients). All patients had undergone prior airway procedures, were high risk based on comorbid conditions, and underwent grafting and reconstruction with a composite supraclavicular island flap. All patients continue to follow up in a multidisciplinary clinic, and at last follow-up, eight of eight patients were successfully decannulated.
CONCLUSIONS
The pSCAIF is a novel method for tracheal reconstruction. The analysis of the prefabricated locoregional approach cohort supports its utility for tracheal reconstruction in patients with complicated multilevel stenosis and adverse comorbidities and characteristics.
LEVEL OF EVIDENCE
4 Laryngoscope, 130:641-648, 2020.
Topics: Arteries; Clavicle; Ear Cartilage; Female; Humans; Male; Middle Aged; Plastic Surgery Procedures; Retrospective Studies; Surgical Flaps; Trachea; Tracheal Stenosis; Treatment Outcome
PubMed: 31112334
DOI: 10.1002/lary.28068 -
Journal of Neuroscience Methods Jan 2020Research using rat as an in-vivo model has played an important role in otological research. The rat ear anatomy has been described; however, detailed surgical procedures...
OBJECTIVES
Research using rat as an in-vivo model has played an important role in otological research. The rat ear anatomy has been described; however, detailed surgical procedures to access the temporal bone are limited. The authors present a technique to approach the inner ear of rat that was standardized by cadaveric dissections and later replicated in living animals.
METHODS
Adult Wistar albino rats were dissected via the post-auricular approach. The emphasis was on early identification of the facial nerve that formed a reliable landmark for the tympanic bulla, which in turn houses the round window and stapedial artery. The point of identification of facial nerve was postero-inferior to the external auditory meatus. The procedure was then repeated in living animals.
RESULTS
Seventeen cadaveric rats were dissected. Initially, the investigators attempted to identify the facial nerve at its crossing over the external auditory meatus. However, that method was found to be unsatisfactory. The facial nerve was then attempted to be identified in its course postero-inferior to the external auditory meatus. The technique improved drastically, and the facial nerve was identified promptly and reliably. The procedure was then repeated in seven living rats under general anaesthesia. The major issues encountered were bleeding from the stapedial artery, hematoma of the pinna in one rat.
CONCLUSION
This study suggests that the post-auricular approach is a feasible and less time consuming route for round window drug delivery experiments in Wistar albino rats. Recognition of anatomical landmarks, particularly the facial nerve is the key to surgery.
Topics: Animals; Carotid Artery, Internal; Facial Nerve; Humans; Models, Animal; Neurosurgical Procedures; Rats; Round Window, Ear; Stapes
PubMed: 31669291
DOI: 10.1016/j.jneumeth.2019.108481 -
Veterinary Anaesthesia and Analgesia Sep 2021To use American College of Veterinary Internal Medicine (ACVIM) criteria to evaluate a high-definition oscillometric (HDO) blood pressure monitoring device versus...
Agreement between invasive and oscillometric arterial blood pressure measurement using a high-definition oscillometric device in normotensive New Zealand White rabbits using two different anaesthetic protocols.
OBJECTIVE
To use American College of Veterinary Internal Medicine (ACVIM) criteria to evaluate a high-definition oscillometric (HDO) blood pressure monitoring device versus invasive blood pressure (IBP) measurement in normotensive rabbits anaesthetized with two different anaesthetic protocols.
STUDY DESIGN
Prospective experimental study.
ANIMALS
A group of 20 healthy adult New Zealand White rabbits weighing 4.36 ± 0.37 kg (mean ± standard deviation).
MATERIALS AND METHODS
Rabbits were premedicated with butorphanol 0.5 mg kg and midazolam 0.5 mg kg subcutaneously (SC, group BMA) or ketamine 25 mg kg and medetomidine 0.4 mg kg SC (group KM). Anaesthesia was induced with alfaxalone administered intravenously (group BMA) or isoflurane by face mask (group KM) and maintained with isoflurane in oxygen. IBP was measured from the central auricular artery. The cuff for the HDO monitor was placed distal to the left elbow and distal to the left tarsus. Agreement between invasive and HDO measurements was evaluated using Bland-Altman method.
RESULTS
In group KM there was better agreement between the HDO device and IBP when the cuff was placed on the thoracic limb, with 100% and 91% of the readings for mean (MAP) and diastolic arterial pressure (DAP), respectively, within 10 mmHg of the IBP measurements. The agreement, although worse, also met the ACVIM criteria for systolic arterial pressure (SAP; 53% of the readings within 10 mmHg). In group BMA, the device met the criteria with the cuff on the thoracic limb only, and only for MAP and DAP (73% and 75% of the measurements within 10 mmHg of the IBP, respectively) but not for SAP (12%).
CONCLUSION AND CLINICAL RELEVANCE
The HDO device met most of the ACVIM criteria for noninvasive blood pressure measurement in anaesthetized rabbits, specifically when the cuff was placed distal to the elbow and the anaesthetic protocol included ketamine and medetomidine.
Topics: Anesthetics; Animals; Arterial Pressure; Arteries; Blood Pressure; Blood Pressure Determination; Blood Pressure Monitors; Prospective Studies; Rabbits
PubMed: 34364790
DOI: 10.1016/j.vaa.2021.03.016 -
ESC Heart Failure Dec 2022Our previous study proved that low-level tragus nerve stimulation (LL-TS) could improve left ventricular remodelling by cardiac down-stream mechanisms. However, the...
AIMS
Our previous study proved that low-level tragus nerve stimulation (LL-TS) could improve left ventricular remodelling by cardiac down-stream mechanisms. However, the cardiac up-stream mechanisms remain unknown.
METHODS AND RESULTS
Twenty-eight adult beagle dogs were randomly divided into an MI group (myocardial infarction was induced by permanent ligation of the left coronary artery, n = 10), an LL-TS group (MI plus intermittent LL-TS treatment, n = 10), and a control group (sham ligation with the same stimulation as the LL-TS group, n = 8). Auricular tragus nerve was bilaterally delivered to the tragus via ear-clips connected to a custom-made stimulator. The voltage slowing sinus rate was used as the threshold to set the LL-TS 80% below this level. At the end of 4 weeks post-MI, LL-TS could significantly increase atrial ganglion plex (GP) activity, decreased left stellate ganglion (LSG) activity, reduced LV dilation, and improved ventricular functions. Chronic intermittent LL-TS treatment significantly attenuated left ventricular remodelling via the up-regulation of α7nAChR expression and the down-regulation of MMP-9 level in post-MI LV tissue. The elevated protein and mRNA of MMP-9 levels in remote areas were significantly ameliorated by LL-TS treatment.
CONCLUSIONS
Chronic LL-TS increased GP neural activity and improved ventricular remodelling possibly via α7nAChR/MMP-9 axis.
Topics: Animals; Dogs; alpha7 Nicotinic Acetylcholine Receptor; Heart Atria; Matrix Metalloproteinase 9; Myocardial Infarction; Ventricular Remodeling
PubMed: 36085552
DOI: 10.1002/ehf2.14146 -
Materials Science & Engineering. C,... Feb 2021The present study aimed to develop a new drug delivery system with efficient drug loading and sustained drug release for potential application in transarterial...
The present study aimed to develop a new drug delivery system with efficient drug loading and sustained drug release for potential application in transarterial chemoembolization (TACE). The porous polyvinyl alcohol microspheres (PPVA MS) were prepared by a combination of inverse emulsification and thermal-induced phase separation (TIPS) method, this was followed by the grafting polymerization of sodium 4-styrene sulfonate (SSS) onto the PPVA MS to obtain the grafted PPVA-g-PSSS MS. The prepared PPVA MS showed a well-defined spherical shape with 'honeycomb-like' porous structure, which could be readily tailored by adjusting the quenching temperature. In vitro biocompatibility analysis indicated the non-cytotoxic and hemocompatible nature of PPVA MS. The porous structure and presence of ionically charged groups in the PPVA-g-PSSS MS favoured the loading of cationic doxorubicin (DOX) onto the MS through ionic-interactions and demonstrated a sustained drug release pattern. Moreover, the cytotoxicity of DOX-loaded PPVA-g-PSSS (DOX@PPVA-g-PSSS) MS against HepG2 cells and the intracellular uptake of DOX demonstrated the potent in vitro antitumor activity. Furthermore, the central auricular artery embolization in rabbits showed that both the PPVA-g-PSSS and DOX@PPVA-g-PSSS MS could occlude the auricular arteries and induced superior embolization effects, such as progressive ear appearance changes, irreversible parenchymal damage and fibrosis, and ultrastructural alternations in endothelial cells. Besides, the DOX fluorescence was distributed around the embolized arteries, without decreasing its intensity when prolonged embolization up to 15 days. These findings suggest that the newly developed DOX@PPVA-g-PSSS MS could be employed as a promising drug-loaded embolic agent for the treatment of hepatocellular carcinoma.
Topics: Animals; Carcinoma, Hepatocellular; Chemoembolization, Therapeutic; Doxorubicin; Drug Delivery Systems; Endothelial Cells; Liver Neoplasms; Microspheres; Pharmaceutical Preparations; Polyvinyl Alcohol; Porosity; Rabbits
PubMed: 33579501
DOI: 10.1016/j.msec.2021.111889 -
Journal of Neurological Surgery. Part... Oct 2023There are some cases where a radial artery (RA) graft is needed for a high-flow extracranial to intracranial (EC-IC) bypass as the external carotid artery (ECA)...
BACKGROUND
There are some cases where a radial artery (RA) graft is needed for a high-flow extracranial to intracranial (EC-IC) bypass as the external carotid artery (ECA) cannot be utilized as a donor artery. In this report, we describe two cases of extracranial vertebral artery (VA) to middle cerebral artery (MCA) high-flow bypass using an RA graft with an artificial vessel as an alternative bypass technique.
METHODS
The patient was placed supine with a head rotation of 80 degrees. After frontotemporal craniotomy, another C: -shaped skin incision was made at the retroauricular region and the V3 portion of the VA was exposed at the suboccipital triangle. Prior to attempting the high-flow bypass, the superficial temporal artery (STA) was anastomosed to the M4 portion of the MCA as an insurance bypass. The RA graft was anastomosed to the V3 portion of the VA that traveled under the periosteum at the supra-auricular region through an artificial vessel. After RA-M2 anastomosis, an alternative EC-IC bypass, the V3-RA-M2 bypass, was achieved.
RESULTS
Postoperative angiography demonstrated successful graft patency and no perioperative complications were observed in both cases.
CONCLUSIONS
In the cases where a high-flow bypass is required, the V3 portion of the VA is a suitable alternative proximal anastomosis site when the ECA is not a candidate donor. Furthermore, an artificial vessel shows satisfactory protection against graft complications.
PubMed: 37832591
DOI: 10.1055/s-0043-1775989 -
Frontiers in Neuroscience 2022The objective of this pilot study was to identify frequency-dependent effects of respiratory-gated auricular vagus afferent nerve stimulation (RAVANS) on the regulation...
BACKGROUND
The objective of this pilot study was to identify frequency-dependent effects of respiratory-gated auricular vagus afferent nerve stimulation (RAVANS) on the regulation of blood pressure and heart rate variability in hypertensive subjects and examine potential differential effects by sex/gender or race.
METHODS
Twenty hypertensive subjects (54.55 ± 6.23 years of age; 12 females and 8 males) were included in a within-person experimental design and underwent five stimulation sessions where they received RAVANS at different frequencies (i.e., 2 Hz, 10 Hz, 25 Hz, 100 Hz, or sham stimulation) in a randomized order. EKG and continuous blood pressure signals were collected during a 10-min baseline, 30-min stimulation, and 10-min post-stimulation periods. Generalized estimating equations (GEE) adjusted for baseline measures were used to evaluate frequency-dependent effects of RAVANS on heart rate, high frequency power, and blood pressure measures, including analyses stratified by sex and race.
RESULTS
Administration of RAVANS at 100 Hz had significant overall effects on the reduction of heart rate (β = -2.03, = 0.002). It was also associated with a significant reduction of diastolic (β = -1.90, = 0.01) and mean arterial blood pressure (β = -2.23, = 0.002) in Black hypertensive participants and heart rate in female subjects (β = -2.83, = 0.01) during the post-stimulation period when compared to sham.
CONCLUSION
Respiratory-gated auricular vagus afferent nerve stimulation exhibits frequency-dependent rapid effects on the modulation of heart rate and blood pressure in hypertensive patients that may further differ by race and sex. Our findings highlight the need for the development of optimized stimulation protocols that achieve the greatest effects on the modulation of physiological and clinical outcomes in this population.
PubMed: 36570845
DOI: 10.3389/fnins.2022.1038339 -
CJC Open Jan 2022We report the case of an 83-year-old man with paroxysmal atrial fibrillation who underwent successful percutaneous left atrial appendage closure with the LAmbre device,...
We report the case of an 83-year-old man with paroxysmal atrial fibrillation who underwent successful percutaneous left atrial appendage closure with the LAmbre device, being in sinus rhythm at implantation. Suddenly, the patient experienced cardiac tamponade and died within a few minutes. Autopsy revealed a slight protrusion of the LAmbre device into the atrial appendage wall, and pulmonary artery laceration. This is the first published report of pulmonary artery perforation by the LAmbre device. This case highlights the need for a detailed imaging study before this procedure is performed, to assess left atrial appendage movement/contraction in patients in sinus rhythm.
PubMed: 35072032
DOI: 10.1016/j.cjco.2021.07.021 -
Frontiers in Veterinary Science 2023Measurement of arterial blood pressure is recommended in anaesthetized animals to guide perioperative treatment. Invasive blood pressure measurement is considered the...
BACKGROUND
Measurement of arterial blood pressure is recommended in anaesthetized animals to guide perioperative treatment. Invasive blood pressure measurement is considered the gold standard, however it is also technically challenging, requires specialised equipment and carries certain risks. For these reasons, non-invasive blood pressure measurement devices are commonly used and are expected to provide accurate and reliable results. This requirement is particularly true for rabbits, in whom peri-anaesthetic hypotension is commonly observed and in whom perioperative mortality remains disproportionally high. Several authors have compared different non-invasive devices with invasive measurements in rabbits and have reported contrasting results. However, to date no comparison between invasive measurements and the PetMAP device, that has been designed specifically for veterinary medicine, has been reported.
AIM AND HYPOTHESIS
The aim of the study was the comparison of invasive blood pressure measurement with PetMAP in rabbits. We hypothesised that PetMAP would show acceptable agreement with the invasive measurements according to the American College of Veterinary Internal Medicine guidelines.
MATERIALS AND METHODS
Sixteen client-owned rabbits presenting for various surgical interventions were included in the study. Invasive measurements were performed by cannulation of an auricular artery. The PetMAP cuff was applied distal to the elbow according to the manufacturer's guidelines. For each measurement with PetMAP, three invasive blood pressure values were recorded. The mean of the three invasive values was compared with one value measured with PetMAP.
RESULTS
Data collected from 16 rabbits were used for statistical analysis. In the clinical setting, the PetMAP device showed significant overestimation of systolic, diastolic and mean arterial pressure, which were measured in the auricular artery. In addition, the bias was not constant, implying that the device poorly predicted changes in blood pressure.
CONCLUSION
The PetMAP device did not meet any of the American College of Veterinary Internal Medicine recommendations.
PubMed: 37492435
DOI: 10.3389/fvets.2023.1141480