Search results for "Resonance"

Hemostasis in brain tumor surgery using the Aquamantys system

2014

Background: Adequate hemostasis in cranial and spinal tumor surgery is of paramount importance in neurosurgical practice. Generalized ooze bleeding from the surgical walls cavity, coming from neoplastic vessels or nervous tissue, may be problematic. Recent technical advances have dramatically reduced intraoperative complications related to blood loss. Several techniques are usually employed to control hemostasis in tumor surgery, including preoperative embolization, intraoperative hypotension, electrical coagulation, and local application of fibrin sealants or hemostatic matrix, which influence coagulation. Material/Methods: Our aim in this study was to evaluate the efficacy and the safety …

Changes in the Spectral Characteristics of Ventricular Fibrillation in Lesions Produced by Radiofrequency Ablation. An Experimental Study

2008

INTRODUCTION AND OBJECTIVES Although electro- physiological databases contain information about changes in the time domain in lesions produced by radiofrequency ablation, very few data on changes in the frequency domain are available. The aim of this study was to investigate changes in the spectral characteristics of ventricular fibrillation in zones with radiofrequency lesions. METHODS Recordings of ventricular fibrillation were obtained in 11 isolated perfused rabbit heart preparations using a multiple epicardial electrode located on the left ventricular free wall. Spectral parameters derived by Fourier analysis before and after the creation of transmural radiofrequency lesions were compa…

Unexpected Persistent Dentocentral Synchondrosis of C2.

2017

Background The persistence of synchondrosis in adulthood can confound diagnostic decisions made during patient management. Case Description A 59-year-old woman who presented neck pain, acute headache, and acute cervical myelopathy symptoms after suffering whiplash grade 3 in a car rear-end impact underwent a conventional radiologic study that revealed no fracture and no anatomic spine variations. The magnetic resonance imaging study revealed no spinal cord intensity signal changes, but it showed a persistent (remnant) dentocentral synchondrosis that was undetected in a previous conventional radiographic evaluation. Conclusions The localization and level of the remnant of the dentocentral sy…

Misdiagnosis of Thoracolumbar Posterior Ligamentous Complex Injuries and Use of Radiographic Parameter Correlations to Improve Detection Accuracy

2019

Study Design Retrospective study. Purpose To evaluate radiological parameters as indicators for posterior ligamentous complex (PLC) injuries in the case of limited availability of magnetic resonance imaging. Overview of Literature Traumatic thoracolumbar spinal fractures with PLC injuries can be misdiagnosed on X-rays or computed tomography scans. This study aimed to retrospectively assess unrecognized PLC injuries and evaluate radiographic parameters as indicators of PLC injuries requiring surgery. Methods In total, 314 patients with type A and type B2 fractures who underwent surgical treatment between 2001 and 2010 were included. The frequency of misdiagnosis was reassessed, and radiograp…

Coronary artery and bypass flow measurement—basic methodology and current status

1998

The starry sky liver: multiple biliary hamartomas on MR cholangiopancreatography

2018

The starry sky liver: multiple biliary hamartomas on MR cholangiopancreatography

The “geographic” liver

2018

Common pitfalls when using the Liver Imaging Reporting and Data System (LI-RADS): lessons learned from a multi-year experience

2018

The goal of the Liver Imaging Reporting and Data System (LI-RADS) is to standardize the interpretation and reporting of liver observations on contrast-enhanced CT and MR imaging of patients at risk for hepatocellular carcinoma. Although LI-RADS represents a significant achievement in standardization of the diagnosis and management of cirrhotic patients, complexity and caveats to the algorithm may challenge correct application in clinical practice. The purpose of this paper is to discuss common pitfalls and potential solutions when applying LI-RADS in practice. Knowledge of the most common pitfalls may improve the diagnostic confidence and performance when using the LI-RADS system for the in…

Ventrolateral Compression of the Brain Stem in Essential Hypertension: MR Angiography Study

1997

Our purpose was to evaluate neurovascular compression at the level of ventrolateral medulla and NVC with the IXth and the Xth cranial nerves in patients with essential hypertension and in healthy volunteers using high resoluted Spoiled Recalled Gradient Echo (SPGR) sequences, allowing the detection of stationary tissues and moving spins. Thirty patients (19 men and 11 women) with essential hypertension were examined. Patient's ages ranged from 24 to 64 years-old (mean age was 48 y.o.). Patients older than 65 were excluded. The average of systolic blood-pressure of hypertensive patients was 183 ± 10 mmHg, while the diastolic pressure was 98 ± 10.5 mmHg. In conclusion, we consider axial sing…

The Role of Magnetic Resonance Imaging in Central Hearing Deficits: Beyond the Acoustic Schwannoma

1997

Acoustic schwannoma is assumed to be the most common cause of sensory-neural hearing loss (SNHL), and many papers have described the role of magnetic resonance imaging (MRI) in the diagnosis of cerebello-pontine angle (CPA) tumours, particularly schwannoma. We retrospectively examined 72 patients complaining of different clinical syndromes and SNHL or different kinds of acoustic impairment who underwent MRI brain study excluding the presence of acoustic schwannoma and other CPA masses. In conclusion, although acoustic schwannoma is the most common cause of acquired HD, a lesion involving the neural centers of the acoustic pathway can also determine SNHL or HD. Considering the high sensitiv…