1,191 research outputs found
Environmental noise and hearing loss
No full textWe are all living constantly surrounded by noise. It is present in the cities, in work environments and in every house, where we are subjected to sounds and music produced by radios, televisions, smartphones and headphones. The most annoying noise is the one produced by cars and public transportation, followed by music, sounds coming from TV and radio, conversations between groups of people and electrical appliances. Hearing loss is more pronounced in people living in urban context. Musicians, both modern and classical, frequently suffer from hearing loss although they do not often perceive symptoms. Also listening to music from portable audio players can expose people to peak levels of 120 dB HL, with regular listening equal to about 100 dB HL for prolonged periods. These kinds of sound exposure can produce at last hearing loss and could assume a relevant epidemiological effect. In conclusion, the noise existing in the environment where we live probably is one of the causes of a slight progressive increasing of hearing loss. This trend is more pronounced in those subjects professionally exposed to noise, although not only factory workers are nowadays at risk. It is necessary, therefore, to inform above all young people about the necessity to avoid exposure to loud noise
Microdrill stapedotomy for otosclerosis with small and large preoperative air-bone gap: a retrospective comparison of results
No full textBackground: In otosclerosis mixed hearing loss is the most frequent symptom and arises when the focus involves the stapes footplate. Surgeons usually prefer to wait a minimum air-bone gap of 25–35 dB before surgery. Objectives: To evaluate the outcome of microdrill stapedotomy for otosclerosis in patients with a preoperative air-bone gap (ABG) <25 dB versus patients with a preoperative gap ≥ 25 dB. Material and methods: For this retrospective study, the outcomes and complications after microdrill stapedotomy were compared between adult patients with a preoperative small ABG (n = 127, ABG <25 dB) and those with a large ABG (n = 254, ABG ≥25 dB). Results: The postoperative ABG was significantly smaller than the preoperative ABG (p <.05) in both groups; there were no differences in complications rates (severe sensorineural hearing loss, footplate fracture or early postoperative vertigo) between the two groups. Conclusions: Our findings show that microdrill stapedotomy is safe and can be performed even in patients with a preoperative small ABG without increasing the risk of sensorineural hearing loss due to inner ear damage
Evolution of symptoms in Ménière's disease
No full textBACKGROUND: Ménière's disease (MD) is a complex illness characterized by the typical association of acute onset of vertigo lasting less than 12-24 hours and low-frequency sensorineural fluctuating hearing loss. In our cohort of patients, MD manifested immediately as its definite form in about 35% of cases whereas in the remaining 75% of cases the pathology started as a monosymptomatic form. METHODS: In order to determine the temporal relationship among these two forms, we evaluated the clinical history on 283 patients affected by definite MD. RESULTS: The very first symptom of MD resulted more frequently the hearing loss. The average time delay between the onset of the first and the second symptom resulted within one year. The risk of onset of the definite form after the first symptom was about 80% within 5 years. The transition from the monosymptomatic form the definite form was quicker in case of vertigo happened as the first symptom. CONCLUSIONS: In conclusion the most frequent layout of onset of MD is a unilateral low-frequency sensorineural fluctuating hearing loss fol lowed by the appearance of vertigo within 5 years. According to the MD guidelines proposed in 1995, all patients referring such kind of hearing loss should be treated as MD, in order to prevent the subsequent occurrence of vertigo
Ossicular Chain Lesions in Tympanic Perforations and Chronic Otitis Media without Cholesteatoma
No full textOBJECTIVE: The first aim was to determine the prevalence, kind, and functional effects on hearing of ossicular chain suffering (OCS) in chronic otitis without cholesteatoma (NCOM) and tympanic perforations (TP). The second aim was to correlate the findings with clinical parameters and hearing level.MATERIALS AND METHODS: The study group comprised 250 consecutive patients affected by NCOM and who were subjected to tympanoplasty and never operated on before. Each patient underwent preoperative pure tone audiometry. Ossicles were evaluated during surgery. The incidence of OCS in NCOM was reported in 15-62% of the patients.RESULTS: Ossicular chain suffering was found in 26 out of the 250 patients included in the overall sample (10%). It was found in 7% of the patients affected by TP without otorrhea and in 19% of the patients affected by chronic ear discharge with drum perforation. OCS was found most frequently in posterior eardrum perforations and in patients with bilateral disease. The incus was the ossicle most frequently interested by resorption (92% of the patients). The air conduction threshold and air bone gap were more impaired in NCOM than in TP.CONCLUSION: Ossicular chain damages in patients with non-cholesteatomatous middle ear pathologies are not frequent and are present in no more than 10% of the patients, but lesions found were similar to those reported in patients with cholesteatoma. Otorrhea, posterior perforation, and bilateral disease can be considered as good predictors of OCS
Management of acoustic neuroma: A retrospective study
No full textBACKGROUND: Acoustic neuromas (AN) are benign tumors of the vestibulocochlear nerve with classic symptomatology that include unilateral sensorineural hearing loss, tinnitus, dizziness, facial and/or trigeminal neuropathy. There are different treatment options of AN: watchful waiting, microsurgical resection, stereotactic radiation and the choice depends by many variables such age, health and hearing of patients as size, location and growing status of tumor. The objective of this retrospective study is to better understand the differences in demographic, hearing status, symptoms, tumor characteristics in patients affected by AN presenting at our clinic and analyze the factors that influence the therapeutic choice. METHODS: One hundred and three patients affected by AN were included in the study. All subjects underwent a detailed clinical interview and audio-vestibular examination, and magnetic resonance imaging (MRI). Tumor status, growing or stable, was estimated comparing new size to any previous MRI with at least a 6-month interval. Descriptive statistics were used for clinical and demographic features of patients. Therapeutic choices related to subjective symptoms were assessed with the chi-square test. RESULTS: Treatment options in our sample included watchful waiting, surgical resection and stereotactic radiosurgery. Overall, 17 patients (16.5%) pursued surgical resection via the retrosigmoid approach, 3 patients (2.9%) were treated with gamma knife stereotactic radiosurgery and 83 patients (80.6%) underwent watchful waiting. The decision-making process for AN treatment was based on size of tumor, age, and hearing loss; a statistically significant difference was found between the size of tumor and PTA of patients that underwent retrosigmoid surgery. No statistically significant difference was found at chi-square test between the type of treatment and symptoms (P=0.719). The analysis of the data showed that the main elements taken into consideration for surgery were the size of tumor (P<0.000004) and, secondly, the PTA threshold; the latter may be due to the fact that patients with bigger tumors had greater hearing impairment (P<0.001). Disease progression influenced the therapeutic decision making with a positive correlation between tumor progression and surgery (P<0.001). CONCLUSIONS: In our sample active surveillance was the most adopted option for small tumor, slow growth and old age. Microsurgical resection was the preferred treatment in patients with large tumors, hearing deterioration and rapid growth. Stereotactic radiation has been proposed in a few cases of elderly patients with slow growing tumor and mild hearing loss
Menieres' disease symptomatology in relation to the AAO-HNS 1995 guidelines
No full textAim. Meniere's disease (MD) is a complex progressive disorders of the inner ear characterized by sensorineural hearing loss, episodic vertigo, tinnitus and aural fullness. MD diagnosis is essentially clinical and specialized test equipment should not be required. In 1995 the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology - Head and Neck Surgery published recommended guidelines for the diagnosis of the MD (3) classifying it in certain, definite, probable and possible. It was the aim of this paper to determine, in a large series of subjects affected by MD according to the AAO-HNS 1995 criteria, the distribution of the different forms, their relationship with clinical paramters and the aspects of the evolution of the disease over time. Methods. The study group consisted of 384 consecutive subjects affected by MD according to the AAO-HNS 1995 guidelines. In each case we have carried out an exhaustive anamnesis regarding all the aspects of the disease and audiometric threshold. Results. According to AAO-HNS classification 228 subjects (59%) at the moment of the first control in our department were affected by definite MD, 30 (8%) by probable MD and 126 (33%) by possible MD. In this sample, among the 129 subjects of this group 90 (73%) were affected only by hearing loss and 36 (27%) only by vertigo. Age at the beginning of the disease was not different among definite, probable and possible forms while subjects affected by the certain MD were older and presented a longer duration of the disease. Disability level was lesser in the possible forms, condition in which the lower degrees are more represented. Among the 228 definite forms, MD appeared with both vertigo and hearing loss together (temporal delay less than 24 hours) in 79 cases (35%), with hearing loss alone in 96 cases (42%) and with vertigo alone in 53 cases (23%). PTA mean threshold at 0.5-1-2-3 kHz at the first control in the 228 cases of definite MD is worse than in the 90 subjects subjects affected by possible MD in its cochlear form. Conclusion. In conclusion definite form represents the most common form of MD at diagnosis and comprises the most disabling cases. However in the larger part of cases it begin as possible and transforms in definite later, normally within 5 years
Precisión y estabilidad dimensional de poliéteres y siliconas utilizados para la toma de impresiones en prótesis fija
No full textFil: Albera, Hugo Alejandro. Universidad Nacional de Córdoba. Facultad de Odontología; Argentina.Uno de los problemas que afectan y pueden determinar el fracaso de las prótesis fijas es la falta de adaptación o ajuste marginal de las restauraciones finales sobre pilares dentarios convenientemente preparados. Entre los factores que tienen incidencia en estos problemas se pueden mencionar:
1- Incorrecta selección o manipulación de los materiales de impresión. 2- Inapropiada selección de la cubeta, ya sea por: a) la falta de rigidez, pues una cubeta flexible puede ser deformada elásticamente en la zona de las paredes, particularmente si se ejerce indebida presión durante la toma de la impresión. b) la presencia de perforaciones en la cubeta que afecten la recuperación elástica del material utilizado, particularmente cuando esta característica se asocia a flexibilidad (de la cubeta) e inadecuada adhesión del material de impresión a sus paredes. C) el tamaño de la cubeta, ya que los elastómeros no deberian comprimirse más de un 30%, ya que si esto ocurre el material no podrá recuperar su volumen original; por ello es conveniente calcular un margen de seguridad. El espesor de material debería ser 3 a 4 veces mayor que la zona retentiva del maxilar o área a impresionar. d) la ausencia de dispositivos de retención del material o no utilización de adhesivo adecuado, pues puede producirse un desprendimiento parcial o total del material de impresión de las paredes de la cubeta con consecuentes deformaciones. 4- La utilización de una técnica inadecuada, ya sea en: a) la mezcla del material b) el llenado de la cubeta c) la ubicación de la cubeta con material de impresión d) la presencia de humedad excesiva. e) el retiro de la impresión. 5- El inapropiado almacenamiento de la impresión, en cuanto a: a) tiempos sugeridos por el fabricante a) temperatura c) metodología de desinfección 6- La incorrecta confección del modelo en lo que respecta a: a) selección del material de vaciado incompatible con el material de impresión (tipos de yeso, resinas epóxicas, resinas poliuretánicas, troqueles galvanoplásticos) b) proporción indebida de la relación entre los componentes conque se vaciará el modelo (por ejemplo si el material a emplear es yeso densita, la proporción yeso/agua) C) técnica de mezclado, ya sea manual o mecánico d) técnica de llenado e) tiempo de fraguado insuficiente f) elaboración de troqueles individuales ) delimitación del margen protético h) aplicación indebida de laca espaciadora si la estructura a confeccionar es colada
7- Errores durante el cierre del margen cervical del encerado 8- Errores en el procedimiento de investido
9- Imprecisiones durante la colada de las estructuras metálicas 10- Deformación por tracción de los metales inadecuadamente preparados durante la cocción de sobreestructuras cerámicas. Las estructuras o copings obtenidos vía CAD/CAM no eliminan las falencias descriptas anteriormente entre los factores enunciados relativos a la toma de impresiones y obtención de modelos de trabajo, ya que para su
obtención el escaneo o lectura se hace, en la mayoría de los sistemas actuales, sobre modelos o troqueles individuales.Fil: Albera, Hugo Alejandro. Universidad Nacional de Córdoba. Facultad de Odontología; Argentina
Musical note recognition based on the upper adjacent harmonics without the presence of the fundamental frequency
No full textMusical signals are complex periodic waveforms characterized by the sum of different frequencies. In a harmonic complex tone, the lowest frequency is called fundamental frequency (f0), while the other frequencies are called harmonics, and their frequencies are integer multiples of the fundamental. The perceived pitch of a sound is correlated with the fundamental frequency, even though it may be impossible to hear f0 in many situations. In these cases, it is possible to identify the pitch based on the upper consecutive harmonics. This study aimed to evaluate the identification of the notes based on the presence of consecutive harmonics only and to determine the importance of their distance from the fundamental frequency. The study was carried out on 30 normally hearing amateur musicians without perfect pitch. The acoustic signal was characterized by the association of four consecutive and two consecutive harmonics of the middle region notes of the piano keyboard. The correct identification rate ranged between 8 and 100%, with better identification occurring when more harmonics and lower frequencies were present. The results confirm that it is possible to identify a note solely based on the presence of harmonics near the fundamental frequency, especially if it is under 2000 Hz
A case of extensive squamous cell carcinoma of the external auditory canal with multiple negative biopsies
No full textWe present the case of a squamous cell carcinoma of the external auditory canal, with double negative biopsy and an imaging before surgery non indicative. The histological examination of the surgical piece did not found any cellular atypies, and the diagnosis was made based upon the clinical and the postsurgical radiological findings
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