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There are indications that endolymph homeostasis is controlled by intracellular cAMP levels in cells surrounding the scala media. Cholera toxin is a potent stimulator of adenylate cyclase, i.e. it increases cAMP levels. We hypothesized that perilymphatic perfusion of cholera toxin might increase
Ionic activities (K+, Na+, and Cl-) of the perilymph and endolymph of the basal turn were measured using ion-selective microelectrodes in experimentally induced endolymphatic hydrops of the guinea pig. Three months following the obstruction of the endolymphatic duct and sac, the endocochlear
Endolymphatic hydrops of the human inner ear may be localized focally in the pars inferior of the human inner ear.
Endolymphatic hydrops may be found in the human inner ear in patients who in life had suffered from Ménière's syndrome or a variety of other disorders. The degree of endolymphatic
The histologic features of the endolymphatic sac and duct in 23 serially sectioned temporal bones with idiopathic or secondary endolymphatic hydrops were blindly compared with 22 randomly selected, normal temporal bones. In idiopathic hydrops, the pars rugosa of the endolymphatic sac extended out of
OBJECTIVE
The presence of endolymphatic hydrops in the inner ear, which can be detected with gadolinium-enhanced magnetic resonance imaging (Gd-MRI), is widely recognized as the main pathological cause of Ménière's disease (MD). However, the precise mechanisms underlying the development of
OBJECTIVE
The preferential delayed enhancement of the perilymphatic space enables detection of the non-enhancing endolymphatic hydrops present in patients with Ménière's disease. The aim of this study was to evaluate the diagnostic utility of delayed postcontrast 3D FLAIR images and a color map of
The use of electrocochleography (ECochG) in the identification of endolymphatic hydrops in Menière's disease, using either trans-tympanic or extra-tympanic recording techniques, has become very popular. The presence of an enhanced summating potential (SP) component is considered to be a diagnostic
It is known that delayed endolymphatic hydrops (DEH) occurs in patients with unilateral and/or bilateral profound hearing loss. In the ipsilateral and bilateral types of DEH, no audiological tests can be performed on the affected ear because of profound deafness, although these tests can be done in
The evidence for the existence of secondary endolymphatic hydrops in patients with perilymphatic fistulas is reviewed and the indications for treatment of such hydrops in patients with fistulas are discussed. The indications for and results of combined fistula repair by middle ear exploration and
CONCLUSIONS
Using a guinea pig model of experimental endolymphatic hydrops, click sounds of altered polarity showed different latencies and amplitudes in hydropic compared with normal cochleae. Latency changes appeared as early as 1 week after endolymphatic obstruction. This method can help diagnose
OBJECTIVE
Nitric oxide (NO) is likely to be synthesized by nitric oxide synthase Type II (NOS II) action and may partake in the origin of changes of compound action potential (CAP) threshold observed in guinea pigs with induced endolymphatic hydrops. This study aimed to assess the action of a NOS II
Presented are ten cases of patients with perilymphatic fistula and/or endolymphatic hydrops who had tinnitus as a major complaint. Tinnitus and its degree of severity often correlate closely with the state of health or hydrodynamic integrity of the inner ear, as these cases illustrate.
An acute endolymphatic hydrops was induced by the injection of 1.1 mul of artificial endolymph into the scala media of guinea pig cochleas. This volume corresponds with an acute endolymphatic hydrops of 23%. During and after the injection, cochlear function was assessed by measuring the 2f(1)-f(2
A method for the diagnosis of labyrinthine hydrops is proposed that takes advantage of specific physiological features of internal ear functioning. Namely, the basal membrane of the inner ear exposed to a low-frequency tone undergoes synchronous sinusoidal oscillations along its entire length;
OBJECTIVE
Three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging of the inner ear after intratympanic injection of gadolinium, together with magnetic resonance imaging scoring of the perilymphatic space, were used to investigate the positive identification rate of hydrops