Search results for "hearing"
showing 10 items of 473 documents
Recessive hearing impairment in three birth cohort in western Sicily
1999
Sudden sensorineural hearing loss
2019
Sudden sensorineural hearing loss (SSNHL), is an important otological disorder that affects up to 5-20 in 100,000 people. It is characterized by a rapid loss of the hearing, usually unilateral, with a sensorineural hearing loss greater than 30 dB over three consecutive frequencies, in less than 72 hours and can be associated with tinnitus and vertigo. It is a real sensorineural emergency that can become a permanent handicap if not adequately treated. Because of patients recovering rapidly or seeking no medical attention, the true figure might be higher, even if delaying SHL diagnosis and treatment may decrease the effectiveness of treatment. Sudden Hearing Loss can occur at any age but usua…
Screening e post-screening (Audiologia essenziale)
2014
Newborn hearing screening is a type of screening test for the early detection of hearing loss. It can recognize with good accuracy newborns affected by hearing impairment allowing an early diagnosis and intervention and avoiding cognitive and linguistic deficits [1,2,3,4,5,6]. The incidence of bilateral sensorineural hearing loss (SNHL) in Sicily is 2.35 cases per 1000 newborns; this value increases to 2.95 if we consider also unilateral SNHL [2,3] and to 10 cases per 1000 births among infants at risk [7,8,9]. A correct newborn hearing screening programme is based on different protocols depending on the presence/absence of audiologic risk factors: • Newborns without risk factors: [1,2,3] In…
TINNITUS PATIENTS: ETIOLOGIC, AUDIOLOGIC AND PSYCHOLOGICAL PROFILE
2013
Tinnitus represents one of the most frequent symptoms observed in the general population in association with different pathologies, although often its etiology remains unclear. Objective of this work is to evidence the main aspects concerning epidemiology, causes, audiological characteristics and psychological consequences of tinnitus.
Sensorineural hearing loss: Pathophysiology, diagnosis and treatment
2019
Hearing loss is one the commonest disabling diseases affecting populations of all ages worldwide. The impairment of hearing may be the cause of impaired language development in children, the cause of scholarly issues in adolescents, the cause of worsening of quality of life in the adults, and the cause of isolation of aged people. In this book, the authors present the hearing loss in all its facets, starting from the basis of pathophysiology and anatomy, passing through the clinical and instrumental diagnosis and, finally, describing the most important diseases causing hearing loss with reasonable treatment options. A section was dedicated to the imaging of the ear with about 100 original f…
Preface
2019
Auditory brain stem responses in patients with human immunotropic virus infection of different stages.
1992
Thirty patients (26 men, 4 women) with human immunotropic virus infection of different stages were examined. Eleven patients had a history of i.v. drug abuse, nine patients had a history of treated lues infection, and one patient suffered from Kaposi's sarcoma. At the time of the examination, opportunistic infections or acute encephalitis were not apparent in any patient. All patients underwent otoneurological examinations, including pure-tone audiometry, caloric vestibular testing, and recording of the auditory brain stem responses (ABR). Six patients reported onset of hearing impairment during the last 3 yr. Two of them had flat sensorineural hearing loss; in the other cases, pure-tone au…
Quantification and visualization of finite strain in 3D viscous numerical models of folding and overthrusting
2020
Abstract Finite strain analysis and three-dimensional (3D) numerical modeling are important methods to understand the deformation history of rocks. Here, we analyze finite strain in 3D numerical simulations of power-law viscous folding and overthrusting. Simulations with different and laterally varying detachment geometries cause a lateral transition from folding (for thicker detachments) to overthrusting. We compute the 3D finite strain tensor, the principal strain values and their orientations. We compute the Nadai strain, e S , and the Lode’s ratio, ν , representing the strain symmetry (constriction or flattening). We apply Hsu diagrams to visualize strain distribution in e S - ν space, …
Ice deformed in compression and simple shear: control of temperature and initial fabric
2012
AbstractLayered and polycrystalline ice was experimentally deformed in general shear involving axial compression (strain magnitude 0.5-17%) and simple shear (strain magnitude γ = 0.1-1.4). As the temperature is increased from -20°C to -2°C, there is at least a twofold enhancement in octahedral shear strain rate, which coincides with the onset of extensive dynamic recrystallization and a change in grain-size distribution at -15°C. Between -150C and -10°C the c-axis preferred orientation rapidly evolves with the initiation of two-maxima fabrics in shear zones. From -10°C to -2°C there is progressive evolution of a final c-axis pattern that is asymmetric with respect to the direction of shorte…
Granular packings and fault zones
2000
The failure of a two-dimensional packing of elastic grains is analyzed using a numerical model. The packing fails through formation of shear bands or faults. During failure there is a separation of the system into two grain-packing states. In a shear band, local ``rotating bearings'' are spontaneously formed. The bearing state is favored in a shear band because it has a low stiffness against shearing. The ``seismic activity'' distribution in the packing has the same characteristics as that of the earthquake distribution in tectonic faults. The directions of the principal stresses in a bearing are reminiscent of those found at the San Andreas Fault.