Tinnitus in noise-induced hearing loss.

Tinnitus was analysed in 94 patients with noise-induced hearing loss. Tinnitus of a pure tone character was most common followed by narrow-band noises, and a combination of these. A broad-band noise type of tinnitus was the least common finding.

Noisy toys: a possible source of sensorineural hearing loss.

This report focuses attention on the wide-spread availability of toys emitting harmfully loud noises.

The recovery of vascular changes following brief noise exposure.

Histological measures of cochlear vasculature and blood flow were examined in 20 guinea pigs. Sixteen were exposed to octave band noise at 120 dB SPL for 30 min and then permitted to survive after the exposure for 6 h, 18 h, 48 h, or 4 weeks (N = 4 in each group). Control animals were exposed to the laboratory and apparatus but not to the noise and then sacrificed after 48 h (N = 2) or 4 weeks (N = 2).

Cochlear blood flow studied with microspheres. A comparison between two different modifications of the microsphere method.

In albino rabbits, spontaneously hypertensive rats, and guinea pigs, cochlear blood flow was measured with the microsphere method, using radioactively labelled microspheres technique and a gammaspectrometer. This 'conventional' microsphere method was compared with a new technique for measurements of cochlear blood flow: a modification of the 'radioactive' microsphere technique and the soft surface specimen technique. Values obtained for cochlear blood flow by the two different methods were similar.

The correlation between otoscopy and otomicroscopy in acute otitis media during healing.

One hundred ears in 50 children were investigated independently by four otolaryngologists during healing of acute otitis media. Interobserver variations of the tympanic membrane were studied. Clinical findings with otoscopy were correlated with otomicroscopy.

Effect of high intensity impulse noise on the vascular system of the chinchilla cochlea.

Changes in the vasculature of the chinchilla cochlea were quantitatively assessed 45 days after impulse noise exposure of either 155- or 160-dB peak sound pressure level. The condition of the vessels in the lateral wall and spiral lamina of each cochlea was evaluated in terms of 20 morphological parameters. Multivariate statistical analysis identified the parameters that were significantly affected by the noise exposure.

Treatment of acute maxillary sinusitis. Erythromycin base and phenoxymethyl-penicillin (penicillin V).

One hundred patients with acute maxillary sinusitis have been studied. The diagnosis was made clinically and confirmed radiologically, using a roentgenological 6-point score for mucous membrane thickening and secretion. Fifty patients in each group were treated with either erythromycin base or phenoxymethyl-penicillin (penicillin V).

The laser Doppler: a non-invasive measure of cochlear blood flow.

The present investigation demonstrates the utility of the laser Doppler flowmeter to provide a measure of cochlear blood flow dynamics. Cochlear and cutaneous blood flow were compared with arterial blood pressure during and following exposure to Angiotensin II, 5% carbon monoxide, 100% oxygen, mannitol, and saline. The observations indicate that: 1) cochlear blood flow generally parallels cutaneous blood flow; however, 2) when cutaneous beds vasoconstrict (e.

The effect of noise and carbogen on cochlear vasculature.

Histological measures of cochlear vasculature and blood flow were examined in 24 guinea pigs. Six animals were exposed to white noise at 120 dB SPL while breathing carbogen (10% CO2 and 90% O2) for 30 min. Six subjects were noise exposed while breathing air.

Regional blood flow in the rabbit cochlea.

A new technique evaluates microcirculation in the different parts of the cochlea. It is a synthesis of two previously known methods--the microsphere method and the soft surface-specimen method. We studied the cochlear blood flow in ten albino rabbits using nonradioactive microspheres.

The effects of fatal hemorrhage on the cochlear vasculature.

The condition of the cochlear vasculature was evaluated in 7 normal guinea pigs subsequent to fatal aortic hemorrhage. The cochleas were prepared for histological analysis using a soft surface preparation technique. The data analysis revealed two statistically significant differences: an increase in the number of aggregations and plasma gaps in the vessel at the vestibular membrane ( VSVM ) and in the vessel of the spiral prominence ( VSSP ).

Cochlear vascular and sensory cell changes induced by elevated temperature and noise.

The vascular anatomy of the chinchilla cochlea was quantitatively analyzed and compared in animals exposed to 155- or 160-dB impulse noise at normal (37 degrees C) and elevated (40 degrees C) body temperatures. Vascular changes persisted 45 days after noise exposure in all experimental animals. Six variables were most susceptible to change in one or more of the vessels studied: 1) irregularities in the vessel lumen, 2) plasma spaces between red blood cells (RBCs) and the vessel wall, 3) columns of RBCs, 4) variability in density of RBCs, 5) pigment clumps in the stria vascularis, and 6) perivascular cells compressing the vessel lumen.

The vascular anatomy of the gerbil cochlea.

The vascular pattern of the cochlea was studied in 12 adult gerbils (Meriones unguiculatus) using the Berlin blue (Prussian blue) contrast injection technique. The capillary areas of the gerbil cochlea are similar to those of other mammals studied. As in some other mammals, the vessel of the basilar membrane was inconsistently identified in the basal turn.

The effect of impulse noise on cochlear vessels.

Short- and long-term changes in the cochlear vasculature and long-term changes in the sensorineuroepithelium were studied in guinea pigs after they were exposed to impulse noise. Vessel histology and cochlear hair cell loss were assessed, using a surface-preparation technique, and the results showed considerable variability. Hair cell loss and radial tears in the organ of Corti were a common finding in the animals killed four weeks after impulse-noise exposure.

Is there an ototraumatic interaction between noise and solvents?

A review of the literature and four case reports are presented. The patients had all been exposed to noise as well as to organic solvents and they demonstrate a much more pronounced sensorineural hearing loss than would be expected from their noise exposure only. In one of the cases a psycho-organic syndrome due to solvent exposure was verified.

Visual testing with 'preferential looking' in mentally retarded children.

In 21 out of 26 children and young adults with mental retardation visual acuity could be successfully examined with operant preferential looking. There was a good correlation in this group of patients between ocular abnormalities demonstrated in an ophthalmological examination and the visual acuity results.

Noise effects on the cochlear vasculature in normotensive and spontaneously hypertensive rats.

The cochlear vessels and the distribution of red blood corpuscles were studied in normotensive (N) and spontaneously hypertensive (SH) rats with and without noise exposure. The evaluation was made in a double blind manner. Ten N-rats and ten SH-rats were exposed to noise for 8 weeks and terminated immediately thereafter.

Visual acuity testing with preferential looking in mental retardation.

Twenty-six mentally retarded children and young adults, most of them with severe neurological deficits, in the age range 5-24 years, were examined ophthalmologically, and their binocular visual acuities were tested with 'operant preferential looking' according to the technique of Mayer & Dobson (1980). Five of the subjects did not co-operate sufficiently for visual testing, although 3 had no ocular abnormalities that would affect binocular acuity. The visual acuity levels determined with 'preferential looking' ranged from 1.

Temporary threshold shift after exposure to noise and music of equal energy.

Ten voluntary subjects were exposed to 10 min of recorded pop music on five occasions. On five other occasions these subjects were exposed to a noise with level-, frequency-, and time-distribution characteristics, measured in octave-band steps, equal to those of the music. Measurements of temporary threshold shift showed almost equal sensitivity to the two stimuli in four subjects, whereas six others demonstrated marked differences in sensitivity.

Visual assessment with preferential looking techniques in mentally retarded children.

An operant preferential looking technique was successfully used for testing of visual acuity in mentally retarded children with visual dysfunction.

The microsphere surface technique for evaluation of cochlear vessels and circulation. A preliminary report.

A new technique for the evaluation of cochlear microcirculation and cochlear vessels is described. This method is a modification of two previously used techniques, the "soft-surface-specimen method" and the "microsphere method". In this preliminary paper it was found that the microspheres were easily visualised in all cochlear tissues.

The acoustic reflex threshold in relation to noise-induced hearing loss.

In 100 consecutive cases with severe noise-induced hearing loss, pure-tone threshold measurements revealed symmetric hearing losses with maximum shifts at 4000 and 6000 Hz. Acoustic reflex measurements showed that few patients had an elevated pathologic reflex threshold. In contrast, we found a depressed acoustic reflex sensation level (i.

Comparison of subjective and radiological findings during the course of acute maxillary sinusitis.

Some of the most common symptoms and signs of acute maxillary sinusitis were graded and compared with the radiological findings during the course of the disease. Four different treatment modes were used in 176 patients. The radiological and the subjective findings did not differ among the groups, which consequently were evaluated as an entity.