Search results for "ULTRASOUND"
showing 10 items of 1259 documents
Intraoperative identification and neurophysiologic parameters to verify pelvic autonomic nerve function during total mesorectal excision for rectal c…
2003
Abstract Background Preservation of parasympathetic and sympathetic nerves is required to avoid urogenital function disturbances after total mesorectal excision (TME) for rectal carcinoma. This study sought to determine whether intraoperative stimulation of parasympathetic nerves with monitoring of bladder contraction is useful in meeting this demand. Study design In a prospective pilot study, 17 patients, 11 men and 6 women, underwent TME with pelvic autonomic nerve preservation performed by an experienced surgeon. The parasympathetic nerves were stimulated by an electrostimulation device (Screener 3625, Medronic), and the resulting bladder contraction was measured manometrically in all pa…
Optical Coherence Tomography Versus Intravascular Ultrasound to Evaluate Coronary Artery Disease and Percutaneous Coronary Intervention
2013
ObjectivesWe compared intravascular ultrasound (IVUS) and 2 different generations of optical coherence tomography (OCT)—time-domain OCT (TD-OCT) and frequency-domain OCT (FD-OCT)—for the assessment of coronary disease and percutaneous coronary intervention (PCI) using stents.BackgroundOCT is a promising light-based intravascular imaging modality with higher resolution than IVUS. However, the paucity of data on OCT image quantification has limited its application in clinical practice.MethodsA total of 227 matched OCT and IVUS pull backs were studied. One hundred FD-OCT and IVUS pull backs in nonstented (n = 56) and stented (n = 44) vessels were compared. Additionally, 127 matched TD-OCT and …
Blood-brain barrier disruption by low-frequency ultrasound.
2006
Background and Purpose— A recent study showed a dramatic increase in cerebral hemorrhage comprising atypical locations with low-frequency ultrasound–mediated recombinant tissue plasminogen activator–thrombolysis in humans. Here, we provide a possible explanation for this phenomenon by a side effect observed in a study using the similar ultrasound device. Methods— The study was originally undertaken to investigate by transcranial Doppler sonography, positron emission tomography and perfusion MRI whether transcranial application of wide-field low-frequency ultrasound (300 kHz) improves cerebral hemodynamics in patients with cerebral small vessel disease. Results— Showing no clear positive ef…
CT after enucleation of renal cell carcinoma.
1994
Computed tomography (CT) was performed in 28 patients 2 weeks to 120 months after enucleation of renal cell carcinoma. The postoperative defect could be exactly localized in all patients. A wedge-shaped (N = 11) or concave (N = 9) morphology was typical. No dependence between morphology of the defect and localization or size of the tumor or the operative technique was observed. The defects were smaller (1.9 cm) than the original prominent tumors (3.6 cm). Defect size was dependent on the operative technique: closure by suture of the renal capsule in smaller defects or by fat flap in larger ones. Postoperative hematomas or delayed perfusion in the adjacent parenchyma were seen in five patien…
Transrectal ultrasound guided implantation of the ProACT adjustable continence therapy system in patients with post-radical prostatectomy stress urin…
2006
Purpose: We evaluate the feasibility and potential advantages of ProACT system implantation using transrectal ultrasound rather than fluoroscopy for guidance. Materials and Methods: The transrectal ultrasound guided procedure was done between June and October 2005 in 7 patients with a mean age of 68.4 years (range 53 to 76) with mild to severe stress urinary incontinence after laparoscopic transperitoneal radical prostatectomy. Results: The ProACT system was successfully implanted in all cases without perioperative complications. Time needed to complete the overall procedure was 15 to 30 minutes. All transrectal ultrasound studies performed during the mean followup of 4.2 months (range 2 to…
Intraoperative ultrasound-assisted approach for endoscopic treatment of vesicoureteral reflux in children
2017
Purpose Despite minimal invasiveness and high success rate, guidelines still prescribe voiding Cystourethrogram (VCUG) after endoscopic treatment for vesicoureteral reflux (VUR) in children. The aim of this paper was to analyze whether intraoperative ultrasound (IO-US) could improve surgical accuracy and perioperative counseling, thus potentially decreasing the need for postoperative VCUG. Methods We selected children treated for moderate to high grade VUR, renal scarring or repeated infections under antibiotic prophylaxis from January to December 2015. Endoscopic injection was combined with IO-US to detect optimal needle placement and to guide mound formation. IO-US findings were compared …
A Survey of Prostate Segmentation Methodologies in Ultrasound, Magnetic Resonance and Computed Tomography Images
2012
Prostate segmentation is a challenging task, and the challenges significantly differ from one imaging modality to another. Low contrast, speckle, micro-calcifications and imaging artifacts like shadow poses serious challenges to accurate prostate segmentation in transrectal ultrasound (TRUS) images. However in magnetic resonance (MR) images, superior soft tissue contrast highlights large variability in shape, size and texture information inside the prostate. In contrast poor soft tissue contrast between prostate and surrounding tissues in computed tomography (CT) images pose a challenge in accurate prostate segmentation. This article reviews the methods developed for prostate gland segmenta…
Cardiovascular dysfunction and vitamin D status in childhood acute lymphoblastic leukemia survivors
2018
Vitamin D (25-OHD) has a role in bone health after treatment for cancer. 25-OHD deficiency has been associated with risk factors for cardiovascular disease, but no data focusing on this topic in childhood cancer survivors have been published. We investigated the 25-OHD status in children treated for acute lymphoblastic leukemia (ALL), and evaluated its influence on vascular function. 25-OHD levels were evaluated in 52 ALL survivors and 40 matched healthy controls. Patients were grouped according to 25-OHD level (< 20 ng/m or ≥ 20 ng/ml). Auxological parameters, biochemical and hemostatic markers of endothelial function (AD, HMW-AD, ET-1, vWFAg, TAT, D-dimers, Fbg, and hs-CRP), ultrasound ma…
Effect of large positioning holes on capsule fixation of plate-haptic intraocular lenses
2000
Abstract Purpose To compare the centration and fixation of silicone plate-haptic intraocular lenses (IOLs) with different-sized positioning holes. Setting Eye Clinic of the Johannes Gutenberg-University Mainz, Mainz, Germany. Methods In a prospective randomized study, 51 Chiroflex C10 and 56 Chiroflex C11 IOLs were implanted under standardized conditions by the same surgeon. The IOL position was documented at the end of surgery and by retroillumination on the first day and 5 months postoperatively. The positioning-hole area was evaluated by ultrasound biomicroscopy (50 MHz) 5 months postoperatively. Results One day postoperatively, no IOL in either group was decentered more than 1.0 mm. Aft…
Echocardiographic and lung ultrasound characteristics in ambulatory patients with dyspnea or prior heart failure.
2013
Purpose Lung ultrasound (LUS) represents a novel, noninvasive method in the assessment of extravascular lung water. We investigated the utility of LUS in ambulatory subjects with dyspnea or prior heart failure (HF). Methods We studied 81 ambulatory subjects with HF history or dyspnea who underwent transthoracic echocardiography (TTE) with LUS of 8 zones. Subjects with heart transplantation or pulmonary conditions known to interfere with LUS were excluded. A reviewer blinded to the clinical data performed echocardiographic measurements and quantified B-lines (reverberation artifacts arising from the pleural line). Results Of 81 subjects, 74 (91%) (median age 66 years, 39% men, median left ve…