Search results for "ACOUSTIC"
showing 10 items of 1590 documents
Management of intralabyrinthine schwannomas
2006
Abstract Objectives Our protocol to manage the intralabyrinthine schwannoma (ILS). Methods Retrospective chart review of 7 consecutive patients managed for ILS. Results Five patients underwent surgical removal of the lesions and none experienced significant complications or recurrent disease. One patient refused surgical treatment and was closely followed by serial MRI scans with no signs of tumor growth. One patient is presently managed conservatively due to a good hearing. Conclusions Diagnosis of ILS is based on high resolution MRI scans and should be included in the differential diagnosis of patients investigated for cochleovestibular symptoms. Treatment modality of ILS is controversial…
Perihepatic lymph nodes and antiviral response in chronic HCV-associated hepatitis.
2003
To identify predictive factors of response to interferon alpha (IFN-alpha) plus ribavirin therapy in patients with chronic hepatitis C (CHC), the presence of lymphadenopathy (LyA) of the hepatoduodenal ligament and other variables were investigated. A total of 110 patients with histologically proven CHC were enrolled in this study. Ultrasound (US) was performed at the start and end of therapy and 6 months after stopping therapy. At baseline, LyA was present in 35 (43.7%) of 80 patients with alanine aminotransferase (ALT) values and grading was significantly higher than in the LyA-negative group. LyA was more frequent in nonresponders (nonR) than in relapsers (relR) or sustained responders (…
Analysis of Internal Jugular Vein Insufficiency—A Comparison of Two Ultrasound Methods
2006
Abstract Jugular venous valve insufficiency is a contributing factor to different pathologic conditions. For assessment of insufficiency, two ultrasound techniques have been developed, that are based on very different methodology (direct Doppler assessment versus air contrast ultrasound venography [ACUV]). This study was conducted to compare these two methods to improve comparability of existing studies and diagnostic accuracy in future studies. The function of 40 valves was determined in 20 individuals during a Valsalva maneuver. For direct Doppler assessment, valvular competence was assessed on basis of Doppler recordings, following recently established criteria. Valvular insufficiency in…
Acute effects of transient vertical whole-body vibration
1991
The question as to whether shock-type whole-body vibration causes increasingly acute strain was investigated. Random vibrations were superimposed with shocks differing in amplitude and in number per unit of time in a systematic manner. The weighted root mean square (rms) acceleration was kept constant in all over the varied experiments. A total of 17 men were exposed to vibration from an electrohydraulic simulator. The following strain criteria were used: biodynamic behavior of the trunk and the head, electrical activity of the muscles of the back and the neck, subjective sensation, skin temperature in the lumbar area and visual and tracking performance. It was found that increasing shock a…
ERP and EOG responses elicited by deviant tones when presented with and without standard tones to reading subjects
2002
Event-related potentials (ERPs) and horizontal electro-oculograms (HEOGs) were recorded in 11 subjects to infrequently presented spatially deviant tones (oddball-deviants) embedded in a series of frequently presented standard tones and also to these deviant tones when presented without the standard tones (alone-deviants). Subjects were instructed to read a self-selected book during the stimulus presentation. The mismatch negativity (MMN), a component of the ERP, was elicited by the oddball-deviants, whereas ERPs to the alone-deviants were characterized by a prominent N1. In an additional counting condition (subjects counting the oddball-deviants), the MMN to the oddball-deviants was followe…
Cochlear origin of early hearing loss in vestibular schwannoma.
2007
Objective: To test whether early hearing loss (HL) is cochlear in origin in patients with vestibular schwannoma (VS). Study Design: Retrospective case review in an academic tertiary referral center. Methods: A group of 19 VS patients with normal/symmetrical hearing and a group of 20 VS patients with mild HL (threshold at any tested frequency better than 45 dB HL) on the tumor ear side. Differences of the amplitudes of the distortion products of otoacoustic emissions (DPOAEs) between the tumor ear and the nontumor ear were studied at frequencies of 1, 1.4, 2, 2.8, and 4 kHz. The Wilcoxon test was used to compare the ears for both groups and to test for possible differences in tumor size betw…
From spatial acoustic changes to attentive behavioral responses within 200 ms in humans
1999
Human event-related potentials (ERPs) and electro-oculograms (EOGs) were recorded in 14 subjects presented with spatially deviant tones in a series of standard tones. In separate sessions, they were instructed to read a book, to count the deviant tones, and to respond to the deviant tones by shifting the eyes towards them from the standard tone source. When reading a book, the mismatch negativity (MMN) of ERP, reflecting pre-attentive detection of acoustic changes, was elicited to the deviant tones at approximately 105-180 ms. No deviance related EOGs were observed in the reading or counting conditions. When the subjects responded behaviorally to the deviant tones, EOGs revealed that the ey…
Effect of Corticosteroids on Facial Function after Cerebellopontine Angle Tumor Removal: A Double-Blind Study versus Placebo
2015
The aim of this study was to assess the effect of corticosteroids administered intra- and postoperatively on the occurrence of facial palsy after a cerebellopontine angle (CPA) tumor resection, and to investigate pre- and intraoperative prognostic factors. A multicenter, prospective, randomized, double-blind and versus-placebo study was conducted between 2006 and 2010. Three hundred and ten patients operated on for a CPA tumor (96% vestibular schwannomas, 4% miscellaneous) were included by five participating centers. The population was stratified into patients with small (≤15 mm CPA on axial MRI views) and large tumors. In each group, patients were randomized to receive corticosteroid (1 mg…
Comparison of electronystagmography results with dynamic posturography findings in patients with vestibular schwannoma.
2007
Condition-5-score (C5S) and condition-6-score (C6S) of computerized dynamic platform posturography (CDPP) can detect the presence of a functional deficit of the lateral semicircular canal (and the superior vestibular nerve), irrespective of the central vestibular compensatory status, in vestibular schwannoma (VS) patients.To test whether CDPP findings differ between VS patients with and without asymmetry on caloric and/or rotational ENG studies.This was a retrospective review of 216 consecutive patients with VS. C5S and C6S of CDPP (Equitest) were compared among patients with normal caloric and rotational studies, patients with asymmetry on caloric studies and normal rotational studies, and…
Dynamic posturography findings predict balance status in vestibular schwannoma patients.
2007
OBJECTIVE To test whether condition 5 score (C5S) and condition 6 score (C6S) of the sensory organization test of computerized dynamic platform posturography (CDPP) differ between vestibular schwannoma (VS) patients with and without vestibular symptoms. STUDY DESIGN Retrospective review of prospectively collected data. SETTING Tertiary academic referral center. PATIENTS Two hundred and sixteen consecutive patients with a histological diagnosis of a VS (103 women; 113 men; age range, 18-78 years; median, 54 years) who had been preoperatively evaluated by CDPP. A hundred and twelve patients had a history of vertigo, dizziness, and/or imbalance, and 104 patients had neither present nor past ve…