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PubMed2001

Barotraumatic blowout fracture of the orbit.

We report a rare case of a barotraumatic blowout fracture of the orbit. A 32-year-old woman presented with sudden swelling of the right orbital region after vigorous nose blowing. Computed tomography scan revealed a blowout fracture of the medial wall of the right orbit with orbital emphysema and herniation of the orbital soft tissue. She was treated with prednisolone and an antibiotic, and did not show diplopia or visual disturbance. Three different theories have so far been proposed to explain the mechanism of blowout fractures, globe-to-wall contact theory, hydraulic theory, and bone conduction theory. The present case indicates that blowout fractures of the orbit can be induced solely by a sudden change of pressure, thereby suggesting the validity of the hydraulic theory.

Adult↗
PubMed1985

On fluctuation of hearing in otitis media with effusion after myringotomy.

Otitis media with effusion (OME) is known to occur in school or preschool children. Its chief symptom is hearing disturbance without otalgia. One of its effective therapies is myringotomy and suction of secretion out of its morbid tympanic cavities. This improvement differs with frequencies. The purpose of this paper is to present the mechanism of hearing recovery after myringotomy. The mean audiogram of OME showed a flat shape with 0 dB of bone conduction and 37.5 dB of air conduction. Hearing level after myringotomy recovered at high tones, but not recovered at low ones. One week later, the mean audiogram without perforations of eardrums showed hearing improvement at low tones. These findings suggested that slower recovery at low tones might be due to incision of an eardrum and closure of its perforation. To confirm this hypothesis we performed an experiment, by which the vibratory mechanism of a thin membrane was disclosed. The result showed that the vibratory modality of a membrane was influenced by incision of it. In conclusion, it is considered that though myringotomy of OME gets hearing improvement, it could result in hearing impairment, probably due to the vibratory modality of an eardrum.

Child↗
PubMed1976

Secretory otitis media due to a hair-bearing dermoid of the mastoid cavity.

A case of persistent unilateral secretory otitis media occurring in an elderly patient is described. The aetiology of the condition proved to be due to a dermoid lying in the mastoid cavity. The clinical, radiological and histological features are described, with comments as to the association which might have existed linking these two conditions. Comment is made concerning the aetiology of dermoid cysts within the mastoid antrum.

Aged↗
PubMed1989

Tuning forks: the problem of striking.

Tuning fork tests have accompanied us from the beginning of otology. Various methods of striking have been used during the century and the efforts to attain standardization appear to have been forgotten since audiology became available. The article reviews the history of the standardization and throws a new light on the production of overtones and air, compared to bone, conduction frequency. The article stresses the importance of tuning fork testing in clinical practice.

Hearing Tests↗
PubMed1994

Tripod allograft in reconstruction of incudal lesions.

Long-term results of allograft ossiculoplasty with erosion of the long process of the incus in 44 patients are described. The pyramidal-shaped allograft leans on the stapes, the remaining part of the incus and the side of the malleus--forming a 'tripod' shape or construction. The study includes two groups of patients: group A (34 patients) in whom the pre-operative three-frequency average air-bone gap was 20 dB or more and group B (10 patients), in whom the pre-operative air-bone gap was less than 20 dB. In the latter group the indication for surgery was not their hearing loss, but a different pathological condition (infected retraction pocket, a cholesteatoma, etc.) which necessitated surgical disconnection of the chain during the operation. The average period of follow-up 46 months for group A and 24.9 months for group B. In group A, the preoperative average air-bone gap was 33 dB. Following surgery, the air-bone gap was 20 dB or less in 27 ears (79 per cent), and 10 dB or less in 18 of them (53 per cent). In group B, pre-operatively, the average air-bone gap was 11 dB. Following surgery, the air-bone gap was either better than before the operation or did not increase by more than 5 dB in eight patients (80 per cent). Comparison of the audiometric results of 20 patients after mean follow-up times of 23.8 months and 64.9 months shows that no deterioration of hearing occurred in the intervening period. Graft extrusion was not observed in any of the operated ears.

Adolescent↗
PubMed1998

Stapedectomy for far-advanced otosclerosis.

Patients with far-advanced otosclerosis (FAO) may appear to be suffering from profound sensorineural hearing loss and are frequently directed to cochlear implantation programmes. In order to avoid such misdiagnosis, FAO should be considered in patients with non-measurable bone-conduction levels and air-conduction levels exceeding 85 dB. Specific clues can lead the clinician to suspect otosclerosis as the aetiology of hearing loss. A review of eight patients (nine ears) with FAO who underwent stapedectomy from 1985-1995 reveals that six of the eight (75 per cent) who had been unable to use a hearing aid preoperatively obtained serviceable hearing with a hearing aid after surgery. This confirms that cochlear implantation is not the best treatment for all profoundly deaf patients; some are better off with stapedectomy.

Aged↗
PubMed1998

Hearing preservation despite labyrinthectomy for resection of giant cholesteatoma with middle fossa extension.

A case is described of an extensive acquired cholesteatoma of the middle ear cleft which had invaded the middle cranial fossa and produced a mass effect on the temporal lobe. It had also extended into the labyrinth without causing elevation in the bone conduction threshold. Furthermore, even after total bony labyrinthectomy, there was very little elevation in these thresholds. The literature relating to hearing preservation after labyrinthectomy is reviewed.

Adult↗
PubMed1984

A double-blind clinical trial of hydroxyethylrutosides in Menière's disease.

A double-blind, placebo-controlled, cross-over trial was undertaken in 39 patients with well-defined Menière's disease. After a one-month placebo run-in period, the patients were assigned, on a randomized basis, to three months' treatment with O-(beta-hydroxyethyl)-rutosides (HR) (2 g./day) followed by three months on placebo, or vice-versa. In spite of a very pronounced placebo effect and a marked tendency to a 'carryover' effect from the first sequence with HR into the second placebo sequence, there appeared to be a clear trend to a greater symptomatic improvement with HR treatment than with placebo. The audiometric findings showed a very clear, uniform superiority under HR treatment, for both air and bone conduction and at all five frequencies studied (250, 500, 1,000, 2,000 and 5,000 Hz.) (p values between 0.002 and 0.05). Indeed, whereas there was a worsening of hearing-loss at each frequency under placebo during the first sequence, this was significantly diminished at each frequency under HR treatment. There were no significant changes in vestibulometry (caloric test) which showed wide variations already during the run-in period. Tolerance to HR treatment was excellent, the incidence of side-effects being similar to that in the placebo periods.

Adult↗
PubMed2006

Is phenol a safe local anaesthetic for grommet insertion?

Two studies were performed to determine whether topical phenol is a safe and well tolerated local anaesthetic for grommet insertion. Study 1 was a retrospective examination of audiological outcomes and complications. Data were obtained regarding 71 procedures in 57 patients. One late infection and nine early extrusions were noted. No statistically significant changes between pre- and post-operative bone conduction thresholds were found. Study 2 was a prospective analysis of patients' perceptions of the procedure. Data from 17 patient questionnaires were analysed as follows: pain rating--not painful, three patients; slightly painful, 14 patients. Overall experience rating--pleasant, four patients; slightly unpleasant, 10; unpleasant, three. All patients stated that they would undergo the procedure again. In conclusion, we found no evidence of phenol-induced hearing loss. The complication rate was within normal limits and patients were satisfied with the procedure. Grommet insertion using phenol as a local anaesthetic is safe and acceptable to patients.

Administration, Topical↗
PubMed2005

The influence of attention and age on the occurrence of mirror movements.

This study utilised a finger force task to investigate the influence of attention and age on the occurrence of motor overflow in the form of mirror movements in neurologically intact adults. Forty right-handed participants were recruited from three age groups: 20-30 years, 40-50 years, and 60-70 years. Participants were required to maintain a target force using both their index and middle fingers, representing 50% of their maximum strength capacity for that hand. Attention was directed to a hand by activating a bone conduction vibrator attached to the small finger of that hand. Based on Cabeza's (2002) model of hemispheric asymmetry reduction in older adults, it was hypothesised that mirror movements would increase with age. Furthermore, it was expected that when the attentional demands of the task were increased, motor overflow occurrence would be exacerbated for the older adult group. The results obtained provide support for the model, and qualified support for the hypothesis that increasing the attentional demands of a task results in greater motor overflow. It is proposed that the association between mirror movements and age observed in this study may result from an age-related increase in bihemispheric activation that occurs in older adults, who, unlike younger adults, benefit from bihemispheric processing for task performance.

Adult↗
PubMed1998

Amount of hydroxyl radical on calcium-ion-implanted titanium and point of zero charge of constituent oxide of the surface-modified layer.

To compare the surface properties of calcium-ion (Ca2+)-implanted titanium with those of titanium and to investigate the mechanism of bone conductivity of Ca2+-implanted titanium, amounts of hydroxyl radical of Ca2+-implanted titanium and titanium were estimated. Also, the point of zero charge (p.z.c.) of oxide constituting surface oxides of Ca2+-implanted titanium and titanium was determined. Results showed that the amount of active hydroxyl radical on Ca2+-implanted titanium was found to be significantly larger than that on titanium, indicating that the number of electric-charging sites of Ca2+-implanted titanium in electrolyte is more than that of titanium. The p.z.c. values of rutile (TiO2), anatase (TiO2), and perovskite (CaTiO3), were estimated to be 4.6, 5.9, and 8.1, respectively. Thus, Ca2+-implanted titanium surface is charged more positively in bioliquid than titanium, accelerating the adsorption of phosphate ions.

Journal Article↗
PubMed2002

Bone formation in transforming growth factor beta-I-loaded titanium fiber mesh implants.

The osteoconductive properties of porous titanium (Ti) fiber mesh with or without a calcium phosphate (Ca-P) coating and osteoinductive properties of noncoated Ti fiber mesh loaded with recombinant human Transforming Growth Factor beta-1 (rhTGF-beta1) were investigated in a rabbit non-critical size cranial defect model. Nine Ca-P-coated and 18 non-coated porous titanium implants, half of them loaded with rhTGF-beta1, were bilaterally placed in the cranium of 18 New Zealand White rabbits. At 8 weeks postoperative, the rabbits were sacrificed and the skulls with the implants were retrieved. Histological analysis demonstrated that in the TGF-beta1-loaded implants, bone had been formed throughout the implant, up to its center, whereas in the non-loaded implants only partial ingrowth of bone was observed. Bone formation had a trabecular appearance together with bone marrow-like tissue. No difference in ingrowth could be observed between the non-TGF-beta1-loaded non-coated implants and the Ca-P-coated ones. All histological findings were confirmed by image analysis: 97% ingrowth was seen in the rhTGF-beta1-loaded implants, while only 57% and 54% ingrowth was observed in the non-loaded Ca-P-coated and non-coated implants, respectively. Bone surface area and bone fill were significantly higher in the rhTGF-beta1-loaded implants (1.37 mm2 and 36%, respectively) than in the non-loaded implants (0.57 mm2 and 26%). No statistical difference was found for any parameter between the Ca-P-coated and noncoated implants. Quadruple fluorochrome labeling showed that in the Ti and Ti-CaP implants mainly bone guidance had occurred from the former defect edge, while in the Ti-TGF-beta1 implants bone formation had mainly started in the center of a pore and proceeded in a centrifugal manner. Our results show that: (1) the combination of Timesh with TGF-beta1 can induce orthotopic bone formation; (2) Ti-fiber mesh has good osteoconductive properties; (3) a thin Ca-P coating, as applied in this study, does not seem to further enhance the bone-conducting properties of a titanium scaffold material.

Animals↗
PubMed1979

Extinction and synesthesia in patients with spinal cord injuries.

Extinction and synesthesia were studied in 50 patients with spinal cord injury with various levels and extents. Extinction was found in 20 (40 per cent) and synesthesia in 6 (12 per cent) of the 40 males and 10 females. No correlations were found between either of the two phenomena and parameters of patient's age, lesion's age, lesion's level and extent, or accompanying head injury. The latter occurred in 22/50 patients (44 per cent), diagnosed by a history of amnesia. Extinction was tested by synchronous double stimulation unilaterally and bilaterally, symmetrically and asymmetrically. It was more frequent unilaterally than bilaterally. The modalities of superficial sensibility were prone to be extinct but those of deep sensibility (pallesthesia from bone conduction and kinesthesia) were not. Extinction of tactile responses did not imply that all other skin modalities (pain, temperature, pressure, skin pallesthesia) will also be extinct in an all or nothing fashion. Modalities could become extinct either singly or in combination. Extinction in spinal man was presumed to be caused by a reduction of perception in hypesthetic areas and was of diagnostic value insofar as its segmental distribution suggested the longitudinal extent of a cord lesion. This concept is in accord with the results of monkey experiments by Eidelberg and Schwartz (1971). Synesthia in spinal man is not identical with synchiria of the monkey. It is not in a reciprocal relationship with extinction and both phonemena co-existed in four of the six patients. Synesthesia is elicited by a stimulus delivered to the normesthetic skin above the level of the lesion with two responses: one well localised at the site of stimulation and the other unilaterally or bilaterally in anaesthetic parts of the body. Five of the six patients reported volitional phantom movements of somatic (toes) and/or visceral (micturition-defaecation) structures. Such sensations are elicited by remembering the engrams of pre-traumatic experiences in areas of the body image connected with motor function. Synesthesia could be understood as a sensory counterpart in areas of the body image when ascending impules of actual perception are mixed with impulses modulated at the artifical synapse of the rostral cord stump creating a phantom sensation.

Adolescent↗
PubMed2000

Fetal exposures to sound and vibroacoustic stimulation.

Sounds in the environment of a pregnant woman penetrate the tissues and fluids surrounding the fetal head and stimulate the inner ear through a bone conduction route. The sounds available to the fetus are dominated by low-frequency energy, whereas energy above 0.5 kHz is attenuated by 40 to 50 dB. The fetus easily detects vowels, whereas consonants, which are higher in frequency and less intense than vowels, are largely unavailable. Rhythmic patterns of music are probably detected, but overtones are missing. A newborn human shows preference for his/her mother's voice and to musical pieces to which he/she was previously exposed, indicating a capacity to learn while in utero. Intense, sustained noises or impulses produce changes in the hearing of the fetus and damage inner and outer hair cells within the cochlea. The damage occurs in the region of the inner ear that is stimulated by low-frequency sound energy.

Acoustic Stimulation↗
PubMed1981

Regulation of vocal intensity in the presence of feedback filtering and amplification.

Subjects read while their voices were fed back with 0 and 20 dB of amplification. In Experiment I, feedback was returned unfiltered or low-pass filtered with cut-off frequencies of 1000, 500, and 300 Hz. Subjects decreased vocal intensity with amplified feedback when the feedback was unfiltered or low-pass filtered with cut-off frequencies of 1000 or 500 Hz. The amplification effect disappeared when the cut-off frequency was 300 Hz. In Experiment II, feedback was low-pass filtered and amplified in the presence of a steady background noise. The presence of noise potentiated the amplification effect in the unfiltered condition. When filtering was introduced and/or the cut-off frequency was lowered, the amplification effect decreased. In Experiment III, subjects heard their voices unfiltered and high-pass filtered with cut-off frequencies of 500, 1000, and 2000 Hz. The amplification effect was the same across filtering conditions. It is suggested that subjects respond differently and high- and low-pass filtering because air- and bone-conducted feedback interact differentially in these conditions. It is hypothesized that changes may be mediated by self-perception of loudness or intelligibility.

Adult↗
PubMed1999

Systemic absorption of gentamicin in the management of active mucosal chronic otitis media.

A prospective study was performed on patients with active mucosal chronic otitis media who were being treated with the gentamicin-containing preparation Gentisone HC. In 27 patients plasma gentamicin levels were measured. Detectable levels were found in 7/27 (26%). Pre- and post-treatment audiometry was performed on 16 patients. There was no statistically significant difference in the change of the mean bone conduction thresholds as a result of treatment, between the treatment and control ears (P = 0.07, Wilcoxon signed Ranks Test at 95% C.I.). We conclude that there is evidence of systemic absorption of gentamicin that would ultimately be absorbed into the perilymph. Gentamicin is known to be ototoxic affecting the vestibular system in lower doses and the cochlea in high doses, hence audiometric assessment is not an appropriate screen for ototoxicity when using topical gentamicin-containing drops. Alternative topical preparations should be further investigated.

Absorption↗