Ultrasound guidance

INTRODUCTION: A novel 3-dimensional (3D) guidance system was developed to aid accurate needle placement during ablation. METHODS: Five novices and 5 experienced hepatobiliary surgeons were recruited. Using an agar block with analog tumor, participants targeted under 4 conditions: in-line with the ultrasound plane using ultrasound, in-line using 3D guidance, 45° off-axis using ultrasound, and off-axis using 3D guidance. Time to target the tumor, number of withdrawals, and the National Aeronautics and Space Administration Task Load Index were collected...

PURPOSE: To evaluate the safety and efficacy of the clinical application of hydrodissection under ultrasound (US) guidance for assisting percutaneous microwave ablation (MWA) for the treatment of renal cell carcinomas (RCCs) adjacent to the intestinal tract. MATERIALS AND METHODS: From April 2014 to December 2016, clinical data from 24 patients with 25 RCCs were retrospectively analysed. Percutaneous MWA under the assistance of US-guided hydrodissection were performed to treat RCCs with a mean maximal diameter of 3...

The current commonly used treatments for cesarean scar pregnancy (CSP) include multiple treatments such as medication, uterine artery embolization, curettage and surgery, and their combinations. However, every treatment option has risks of excessive hemorrhage from uterus. In this study, we retrospectively analyzed the risk factors for intraoperative hemorrhage of different treatments for CSP patients, with the hope to provide the guidance for CSP treatment.Fifty-eight cases of CSP patients who were treated with curettage after medication, curettage after uterine artery embolization, or surgery were retrospectively analyzed and compared for the clinical efficacy, length of hospital stay, and hemorrhage rate...

Background: The aim of this study was to investigate specific bleeding volume after percutaneous renal biopsy (PRB) and the correlation between bleeding volume and clinical parameters. Methods: A retrospective study of 252 consecutive patients (153 male patients and 99 female patients) who underwent PRB at the Department of Nephrology, Japanese Red Cross Ishinomaki Hospital, between July 2013 and January 2016 was conducted. PRB was performed under ultrasound guidance using an automated spring-loaded biopsy device and a 16-cm, 16-gauge needle...

BACKGROUND: Scar pregnancy is an extremely rare type of ectopic pregnancy, where there is implantation of the gestational sac onto the anterior wall of the uterus at the site of previous LSCS scar in a multipara female. Due to a poor vascular supply to the lower uterine segment, caesarean scars may heal improperly predisposing it to be a site of improper implantation of the gestational sac. RESULTS: The characteristic features are empty uterus and cervix, gestational sac in the anterior part of lower uterine segment with a history of painless vaginal bleeding...

BACKGROUND: Complex regional pain syndrome (CRPS) comprises a group of conditions characterized by severe, debilitating pain that is disproportionate to any inciting event and is not distributed in a specific nerve distribution or dermatome. CASE REPORT: A 42-year-old female with a 2-year history of right upper extremity CRPS type I refractory to conventional management underwent an ultrasound-guided and fluoroscopy confirmed percutaneous peripheral nerve stimulation trial with a lead extending from the C6 to the T3 level to cover the cervical and upper thoracic sympathetic chain...

In ultrasound-guided central venous catheterization, there is no standard technique either for the needle tip visualization or for the adequate needle angle and entry to the skin with short-axis view under out-of-plane technique. In the present study, we propose a novel technique named "stepwise flashing with triangulation", and the efficacy of this technique is assessed. Before and after a didactic session in which the technique was explained, 12 novice residents were asked to position the needle tip on or into the imitation vessels and to avoid deeper penetration by using an agar tissue phantom with ultrasound guidance...

Visualization of the catheter during ultrasound-guided continuous nerve block performance may be difficult but is an essential skill for regional anesthesiologists. The objective of this in vitro study was to evaluate 2 newer catheters designed for enhanced echogenicity and compare them to a widely used catheter not purposely designed for ultrasound guidance. Outcomes were the numbers of first-place rankings among all 3 catheters and scores on individual echogenicity criteria as assessed by 2 blinded reviewers...

Ultrasonography is increasingly being viewed as an everyday tool in obstetric anesthesia. For the administration of spinal or epidural anesthesia, it reduces needle redirection attempts in patients with difficult anatomy. In the less frequent scenario of a collapsed patient, it helps with assessment in the form of transthoracic echocardiography. Abdominal blocks require ultrasound guidance for safe and anatomically correct placement. Accurate assessment of gastric volume status with ultrasound would be a useful everyday skill if it is adopted into mainstream practice...

OBJECTIVE: To compare the effectiveness of ultrasound- and electrostimulation-guided nerve blocks of the brachial plexus and to determine whether ultrasound guidance is feasible in conscious dogs. STUDY DESIGN: Blinded, crossover, experimental study. ANIMALS: Six clinically healthy adult Beagle dogs. METHODS: The nerves of the brachial plexus of the right thoracic limb were blocked under ultrasound guidance (UNB) in conscious dogs and under electrostimulation guidance (ENB) in anesthetized dogs with bupivacaine (0...

OBJECTIVE: The objective of this study was to characterize the technique and to report the results of double prepuncture used during complex radiofrequency ablation (RFA) in cases of treating multiple incompetent veins or encountering focal obstruction to catheter advancement. METHODS: A double prepuncture technique was applied in patients requiring endovascular ablation of multiple veins and patients with great saphenous vein cannulation failure. We treated 13 limbs in 12 patients during a 24-month period with RFA in which the double prepuncture technique was used...

BACKGROUND AND OBJECTIVE: Needle-based confocal laser endomicroscopy (nCLE) under endoscopic ultrasound guidance is a newly developed imaging technique for pancreatic lesions and lymph nodes, enabling a subcellular level of resolution. The confocal miniprobe is an invasive instrument designed to be reused up to 10 times. Therefore, a method that ensures the complete elimination of microbial contaminants on the device is necessary. We studied the bactericidal efficacy of the Stella™ system, which purports to achieve this objective...

The objective of this study was to extend an ultrasound surface wave elastography (USWE) technique for noninvasive measurement of ocular tissue elastic properties. In particular, we aim to establish the relationship between the wave speed of cornea and the intraocular pressure (IOP). Normal ranges of IOP are between 12 and 22mmHg. Ex vivo porcine eye balls were used in this research. The porcine eye ball was supported by the gelatin phantom in a testing container. Some water was pour into the container for the ultrasound measurement...

PURPOSES: The purpose of this study was to compare the effects of lateral abdominal transversus abdominis plane block (TAP block) and iliohypogastric/ilioinguinal nerve block (IHINB) under ultrasound guidance for postoperative pain management of inguinal hernia repair. Secondary purposes were to compare the complication rates of the two techniques and to examine the effects of TAP block and IHINB on chronic postoperative pain. METHODS: This was a prospective randomized controlled open-label study...

BACKGROUND: Past catheter-based and focused ultrasound renal denervation studies have indicated that procedure efficacy is related to the number of ablations performed or the amount of energy used for the ablation. This study extends those prior results and investigates energy level effects on the efficacy of MR guided focused ultrasound renal denervation performed in a porcine model. METHODS: Twenty-four normotensive pigs underwent unilateral denervation at three intensity levels...

BACKGROUND: Metastatic tumors to the pancreas are rarely encountered and diagnostically challenging. We aspired to determine the incidence and origin of all metastases to the pancreas at our institution, and to examine their clinicopathologic and cytomorphologic features. We also sought to ascertain the effect of endoscopic ultrasound (EUS) guidance implementation. METHODS: A search of our database was undertaken to review all pancreatic FNA and/or CNB examined from January 2000 through December 2014...

Photoacoustic (PA) and thermoacoustic (TA) effects have been explored in many applications, such as bio-imaging, laser-induced ultrasound generator, and sensitive electromagnetic (EM) wave film sensor. In this paper, we propose a compact analytical PA/TA generation model to incorporate EM, thermal and mechanical parameters, etc. From the derived analytical model, both intuitive predictions and quantitative simulations are performed. It shows that beyond the EM absorption improvement, there are many other physical parameters that deserve careful consideration when designing contrast agents or film composites, followed by simulation study...

Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is a reliable and commonly established technique, enabling real-time guidance of transbronchial needle aspiration of mediastinal and hilar structures and parabronchial lung masses. As EBUS-TBNA became more available and adopted by clinicians, questions emerged about the optimal performance of the procedure. Although EBUS is considered safe, there are few complications that could occur during the test, correlated with both the procedure itself and the patient's characteristics...

In recent years, endobronchial ultrasound-guided TBNA (EBUS-TBNA) has emerged as an innovative technique for diagnosis and staging of lung cancer and has been successfully introduced into daily clinical practice with several advantages including minimally invasive approach, safe, cost-effective, real time image guidance, broad sampling capability, and rapid on-site evaluation (ROSE). Both cytological and histological approach could be useful to have material for diagnosis, immunohistochemical and molecular analyses which may be very important for targeted therapy with successful rate ranging from 89% to 98%...

The precise placement of recording electrodes at the relevant myotome is mandatory while performing pedicle screw stimulation (PSS) during spine surgery; however, their placement at trunk muscles is challenging. This study aimed to determine whether ultrasound guidance is useful for trunk muscle localization for PSS during spine surgery. A retrospective clinical study was conducted from a prospective database. Eighty-four patients eligible for spine surgery were recruited. Ultrasound was used to localize the intercostal, rectus abdominis, and internal oblique and psoas muscles if pedicle screw placement was performed at T3 to L1...