Aminoglycoside antibiotics.

In the 50 years since their discovery, the aminoglycoside antibiotics have seen unprecedented use. Discovered in the 1940s, they were the long-sought remedy for tuberculosis and other serious bacterial infections. The side effects of renal and auditory toxicity, however, led to a decline of their use in most countries in the 1970s and 1980s.

The role of midfacial degloving in modern rhinological practice.

The midfacial degloving approach has been available for twenty five years and is slowly increasing in popularity in the management of extensive benign lesions of the sinonasal region, for selected malignancy in this area and to afford access to the nasopharynx and infra-temporal fossa. The advantages, applications and low complication rate are presented in a cohort of 86 patients, ranging from three to 79 years of age with a mean follow-up of 5.5 years.

Indications of different distortion product otoacoustic emission mechanisms from a detailed f1,f2 area study.

The primary site of generation on the basilar membrane for the 2f1-f2 distortion product (DP) is generally considered to be near where the higher-frequency stimulus tone peaks. This site has also been shown to be a source of DP otoacoustic emission (DPOAE) in the ear canal, but a second source of emission is known to exist in the region of the DP frequency place. The DPOAE phase versus frequency gradient provides a means of investigating the emission mechanisms.

Apoptotic death of hair cells in mammalian vestibular sensory epithelia.

Hair cell death was examined in cultured explants of vestibular organs from mature guinea pigs and gerbils. The effects of gentamicin were compared with those of staurosporine, a membrane-permeable kinase inhibitor that induces programmed cell death in almost all cell types. Under the conditions used staurosporine killed hair cells but supporting cells appeared unaffected, and a topographic pattern of differential sensitivity to staurosporine amongst hair cells, similar to that described for aminoglycoside antibiotics, was revealed.

A treatment algorithm for the management of epistaxis in hereditary hemorrhagic telangiectasia.

We examined the management options used for epistaxis of varying severity in patients with hereditary hemorrhagic telangiectasia (HHT) to develop a treatment algorithm. Fifty patients with HHT were studied from 1991 to 1997 to consider various treatment options and their relative efficacy. There were 28 females and 22 men; their ages ranged from 15 to 85.

Gap junctions and connexin expression in the inner ear.

Several different recessive mutations in the connexin26 (Cx26; beta 2) gene have been associated with non-syndromic hereditary deafness. This suggests gap junctions are important to cochlear function. Numerous large gap junctions are present between adjacent supporting cells in both the vestibular and auditory sensory epithelia of the mature inner ear.

Tinnitus after head injury: evidence from otoacoustic emissions.

Objective: Tinnitus may be caused by a lesion or dysfunction at any level of the auditory system. This study explores cochlear mechanics using otoacoustic emissions in patients with tinnitus after head injury, in whom there seems to be evidence to support dysfunction within the CNS.

Methods: The study included 20 patients with tinnitus and other auditory symptoms, such as hyperacusis and difficulty in listening in background noise, after head injury, in the presence of an "intact" auditory periphery (normal or near normal audiometric thresholds).

Presence of tinnitus indicated by variable spontaneous otoacoustic emissions.

Spontaneous otoacoustic emissions (SOAE) have been widely studied in normal subjects, and there is evidence of their high frequency stability in repeated recordings. A study to determine the frequency stability of SOAE in 53 of 100 consecutive patients, who presented with tinnitus and in whom SOAE were recordable, was undertaken. Patients were divided into five aetiologically homogeneous subgroups: (i) those with normal hearing and no identified pathology, (ii) those with sensorineural hearing loss of unknown origin, (iii) those with normal hearing, but complaining of tinnitus related to head injury, (iv) those with endolymphatic hydrops, and (v) those with noise exposure.

Hair cell recovery in the vestibular sensory epithelia of mature guinea pigs.

The progression of recovery of the vestibular sensory epithelia of guinea pigs after gentamicin-induced hair cell injury was assessed quantitatively and qualitatively. Evaluations were made of the number of cells bearing hair bundles by using scanning electron microscopy (SEM) and of identifiable hair cells in thin sections. Both assessment procedures showed that an initial loss of hair cells in utricular maculae is followed by significant recovery in the number of hair cells present.

Intercellular junctional maturation in the stria vascularis: possible association with onset and rise of endocochlear potential.

The postnatal maturation of intercellular junctions of marginal and basal cells of the stria vascularis was examined in the gerbil using thin sections and freeze fracture techniques. Immunohistochemical methods were used to determine the presence of Na,K-ATPase postnatally. The onset and growth of endocochlear potential (EP) was also measured.

Effect of fluticasone in severe polyposis.

Objectives: To investigate the effect of intranasal corticosteroids in the treatment of polyps in patients with severe polyposis listed for surgical treatment and to determine the treatment effect on the progression of the disease.

Design: A double-blind, randomized, parallel-group, placebo-controlled, 12-week study at a single center.

Setting: A tertiary referral center in London, England.

Craniofacial resection for tumors of the nasal cavity and paranasal sinuses--a 17-year experience.

Background: The rarity of sinonasal tumors has precluded long-term follow-up of large series of craniofacial resections until now.

Methods: A series of 209 patients suffering from a wide range of histologies who had undergone craniofacial resection for sinonasal neoplasia with up to 17 years' follow-up were analyzed.

Results: An overall actuarial survival of 51% at 5 years and 41% at 10 years was found for the cohort as a whole.

Postnatal maturation of the organ of Corti in gerbils: morphology and physiological responses.

The organ of Corti, the sensory epithelium of hearing in mammals, matures postnatally in the gerbil. Quantitative analyses of the postnatal development of the organ of Corti, including supporting cells and the basilar membrane, were carried out. The morphological study confirmed that maturation of the sensory cells proceeds with a base-to-apex gradient, with the outer hair cells appearing to mature before the inner hair cells.

Staging for rhinosinusitis.

Interest in the surgical treatment of chronic rhinosinusitis has increased, primarily because rigid endoscopy and, more particularly, computed tomographic scanning have facilitated the visualization of disease. At the same time it has become both scientifically and financially imperative to audit therapeutic outcome. Consequently, a staging system for nonneoplastic sinus disease is needed.

Loss and survival of spiral ganglion neurons in the guinea pig after intracochlear perfusion with aminoglycosides.

Loss of cochlear hair cells results in a loss of ganglion cells and further neurodegenerative changes throughout the auditory pathway. Understanding more about the early stages of ganglion cell loss in vivo may lead to ways of ameliorating or preventing the loss of these neurons. To examine these stages, the effects of intracochlear perfusion with aminoglycoside antibiotics on the organ of Corti and spiral ganglion cells were evaluated in young adult guinea pigs at survival periods ranging from 1 hour to 12 weeks, using immunocytochemical and ultrastructural techniques.

Morphological evidence for supporting cell to hair cell conversion in the mammalian utricular macula.

The possible origin of the immature hair cells that appear in the utricular maculae of guinea pigs following gentamicin-induced hair cell death was investigated. Guinea pigs were continuously infused with bromodeoxyuridine, to label proliferating cells and their progeny, for 2 weeks after inducing damage to the inner ear on one side with gentamicin. The opposite ear in each animal served as control.

Structural development of sensory cells in the ear.

The hair cells of the auditory and balance systems of the inner ear have precise structures and orientations related to function. Hair cells differentiate from a homogenous cell population with the initiation of afferent synaptogenesis and appearance of the apical hair bundle being the first definitive structural sign of hair cell development. The cytoskeletal network then develops and the intercellular membrane junctions become more complex.

Latency of contralateral sound-evoked auditory efferent suppression of otoacoustic emissions.

The suppression of transiently evoked otoacoustic emissions by contralateral sound stimulation is thought to occur as a result of the action of the efferent pathway from the superior olivary complex to the cochlea via the medial olivo-cochlear neurons. The purpose of this study was to determine the time taken for this pathway to activate the suppressive mechanism in response to contralateral sound in normal human subjects. The time for onset of suppression was found to be between 7 and 20 ms.

Abnormal audiograms and elevated acoustic reflex thresholds in obligate carriers of autosomal recessive non-syndromic hearing loss.

Pure-tone audiograms and acoustic reflex thresholds were obtained in 24 presumed obligate carriers of autosomal recessive non-syndromic hearing loss and 30 sex and age appropriate control subjects, with a view to evaluating the prevalence of abnormalities on these tests in the two groups, and a possible link between the findings on the two tests, which may help to localize threshold deficits and/or abnormal configurations to different sections of the reflex arc. Six (25%) of the carriers and one control subject had abnormal audiograms, inferred to be of genetic aetiology through careful exclusion of environmental risk factors. Four additional carriers had acoustic reflex threshold abnormalities.

Rhinosinusitis.

Rhinosinusitis, inflammation of the lining of the nose and paranasal sinuses, has a range of different causes. This article considers the classification, diagnosis and treatment of rhinosinusitis.