Biomedical subjects

M Rosignoli

Publications and source records attributed to M Rosignoli.

At least 37 records · Page 2Linked to original sources

PubMedDate not supplied

Clinical applicability of transient evoked otoacoustic emissions: identification and classification of hearing loss.

The study aimed at the development of a clinically applicable methodology that could: (1) discriminate transient evoked otoacoustic emission (TEOAE) recordings from normal hearing or hearing impaired individuals; (2) classify the nature of the hearing loss as conductive or as cochlear, and (3) define clear-cut TEOAE clinical criteria. A classification algorithm based on a multivariate discriminant analysis of fast Fourier transform data from recordings evoked by click stimuli of 50 +/- 2, 62 +/- 2, 68 +/- 2 and 80 +/- 2 dB SPL was used to discriminate 302 normal subjects from 383 subjects suffering from mild to moderate hearing losses. The best discriminant model (QDF80) produced a sensitivity of 93.8% and a specificity of 79.4%. When extra correlation criteria were serially applied to the classification outcome, the specificity was increased to 85.3%, but the sensitivity was marginally decreased to 91.7%. The classification of the correctly identified hearing-impaired cases yielded 93.8% identification of conductive and 75.1% identification of cochlear cases. A sensitivity analysis of the misclassified hearing-impaired cases suggested that the TEOAE spectra are well correlated with the 2-kHz but poorly correlated with the 4-kHz octave frequency.

Acoustic Stimulation↗

PubMedDate not supplied

The behaviour of wave V latency in cochlear hearing loss.

The audiological approach to the early diagnosis of cerebellopontine angle tumours (APC) is based mainly on ABR. In present work, wave V latency has been studied in two groups of patients: 308 cochlear cases and 74 retrocochlear cases (APC surgically confirmed tumours), in order to increase the sensitivity and specificity of the diagnostic indexes I-V, IT5 and Delta V. Wave V latencies have been evaluated in relation to hearing loss at 2-4 kHz and audiometric profile. Both these factors show a highly significant positive correlation with the latency, which consequently increases proportionally to hearing loss and high-frequency audiometric loss. A multiple regression analysis was therefore used to analyse the effects from the two variables, and a correction factor was calculated to compensate the latency values for hearing loss and threshold configuration. The effects of such a correction on the clinical results consist mainly of a reduction in the rate of cochlear false-negative results, which corresponds to improving the ABR specificity.

Audiometry, Evoked Response↗

PubMedDate not supplied

Audiometric patterns of genetic non-syndromal sensorineural hearing loss.

Sixty-five families with non-syndromal sensorineural hearing loss (NS-SNHL) of genetic aetiology were subtyped according to Gorlin et al. Individual audiogram shapes were also classified in order to detect inter- and intra-familial variations. In 48 families with an Autosomal Dominant (AD) inherited form, 26 exhibited the features of (high-frequency) progressive NS-SNHL, 12 those of mid-frequency NS-SNHL, 5 were affected by congenital low-frequency NS-SNHL; 1 kindred showed a progressive low-frequency pattern and another 1 a unilateral NS-SNHL; only 3 kindreds were affected by severe congenital NS-SNHL. Autosomal Recessive (AR) inherited forms were composed of 9 kindreds with severe congenital NS-SNHL, and 7 with moderate congenital NS-SNHL. One X-linked form was identified. AD- and AR-inherited NS-SNHL differed significantly both in severity of hearing impairment and in audiogram shapes. With few exceptions, in each family classified according to Gorlin, most of the affected subjects shared the same audiogram profile. Intrinsic progression of the disease versus ageing was studied in the larger subtype of individuals with the high-frequency loss. Gorlin's classification still remains the best system to classify NS-SNHL, and can provide a broad base to separate a very heterogeneous group of disorders. Results obtained in gene mapping in single large human families or in homologous gene search could be tested in our families. For some of them, namely those with high frequency progressive and low-frequency NS-SNHL, testing should already be feasible.

Adult↗

PubMedDate not supplied

Cisplatin ototoxicity in the Sprague Dawley rat evaluated by distortion product otoacoustic emissions.

The present study has evaluated the use of distortion product otoacoustic emission (DPOAE) responses in the detection of cisplatin-induced ototoxicity in a Sprague Dawley rat animal model. The cisplatin was administered as a 16 mg/kg, dose introduced by a slow 30-min intraperitoneal infusion. Data from three DP-gram protocols, DPOAE input-output responses at 8 kHz, and auditory brainstem responses (ABRs) at 8, 12 and 16 kHz were collected before and 72 h after treatment. The post-treatment ABRs at 16 kHz showed the greatest mean threshold shift of 33.6 dB. The post-treatment DP-gram data showed significant reduction of the signal to noise ratios in the majority of the frequencies tested, across all tested protocols. The data suggest that the most sensitive DPOAE procedure for the early detection of the cisplatin-induced ototoxic damage is the DPOAE I/O protocol. Morphological analyses indicated that the inner hair cells remained intact, while several types of alterations were observed in the arrangement of the stereocilia in the outer hair cells.

Animals↗

PubMedDate not supplied

Hearing in the elderly: a population study.

An epidemiological study comparing speech audiometry with self-assessed hearing disability and an analysis of other factors influencing the quality of life was conducted. In the Veneto region (Italy), a representative sample of 2700 independently living individuals of 65 years of age and older was selected for the study. All participants were administered a comprehensive questionnaire and a brief examination at their home, including a general physical examination, speech audiometry, Sanders' Speech Disability test, part I and III, Mini Mental State Examination, CES-D scale for depression, visual acuity, self-reported diseases and physical function. Auditory function was worst in the older individuals: auditory performance was within acceptable limits up to the 75-79 age group, while it rapidly deteriorates in the older groups. This trend is consistent with self-reported auditory disability (Sanders' test). A detailed analysis of the type of errors made in the speech audiometry was conducted for each subject. Speech audiometry is a good indicator of real hearing difficulties faced by the elderly, and it might be preferred to pure-tone audiometry, since hearing deficits with age are not always limited to an increased detection threshold, but include other aspects of hearing such as distortion of sounds, comprehension of speech and noise discrimination.

Age Distribution↗

PubMedDate not supplied

[Invasive nasosinusal aspergillosis in an immunocompetent patient].

The authors describe a case of invasive nasosinusal aspergillosis in an immunocompetent patient. After a careful bibliographic review, they emphasize that in the present case the diagnosis was made by means of fungal culture as the clinical picture, imaging techniques and histopathological findings were aspecific. The pathogenetic agent resulted Aspergillus tamarii which belongs to the Aspergillus flavus group and is one of the most unusual agents in literature. The treatment of choice, in the invasive form, is surgery that should be as radical as possible followed by a medical therapy. In the present case, after two-phase radical surgery on all the paranasal sinuses, medical treatment with traconazole was employed with excellent local results at a follow-up of one year.

Adult↗

PubMedDate not supplied

[Considerations on analysis time duration in a posturographic study in normal subjects].

In order to evaluate the importance of analysis time on posturographic parameters (average X, Y and R, Sway Path, Sway Area, Ellipse Area) both with eyes open and closed, 24 normal subjects were examined for an overall period of 60 seconds. Mean +/- 1 SD values of each parameter were obtained for each time interval (0-20, 20-40, 40-60 sec.) into which the overall period was divided. With the eyes open, the parameters for each time interval did not differ significantly and they were always lower than those obtained with the eyes closed. On the other hand, with the eyes closed, there was a significant reduction in the various parameters as analysis time progressed. In 4 out of 24 subjects an inverse behaviour was detected. The authors conclude that the open-eye analysis time could be limited to 20 sec while, due to changes observed in the various posturographic parameters, closed-eye analysis time should be extended to 60 seconds. The analysis time may prove important in identifying peripheral or central vestibular pathologies since it may be that some of them induce earlier alterations of posturographic parameters while in other pathologies such changes are observed later on.

Adult↗

PubMedDate not supplied

[Our experience with mandibular fractures].

The authors relate on their own experience concerning etiology, diagnosis and treatment of mandibular fractures. 320 patients (252 males and 68 females) aged between 6 and 82 years with posttraumatic fractures of the mandible, 188 with a single and 132 with multiple fractures, underwent surgical and/or orthopedic treatment. Interosseous wiring and seldom application of metallic plates were the preferred techniques when surgery was performed. Intermaxillary fixation was carried out when the orthopedic treatment was needed. Often both methods were associated. In 10% of the condylar fractures the condyle has been removed. Functional results were excellent and no serious complications could be observed. In 11% of the cases with condylar fractures some limitation of the mandibular movements could be observed, while when condyles were not involved malocclusion could be observed in 3% of the cases. The authors discuss upon etiology, by comparing their own with other experiences, upon diagnosis, which does not seem difficult if adequate radiological investigations are carried out; finally they relate briefly on the advantages and disadvantages of the different surgical and non surgical techniques. Based on their experience they conclude that interosseous wiring and, in selected cases, the application of metallic plates, using an external approach, mostly associated with intermaxillary fixation, represent a safe and adequate treatment for almost every fracture of the mandible.

Adolescent↗

PubMedDate not supplied

[Influence of static stimulation of cervical and otolithic receptors on posturographic parameters].

In the present work 30 normal adult subjects (20 males, 10 females; age range 25-40 years) having no signs or symptoms of vestibular involvement were studied in order to verify whether posturographic parameters could be influenced by the static stimulation of cervical and otolithic receptors. The posturographic evaluation was carried out using a stabilometric platform (Bertec) with the subject standing and the head in one of the following positions: median position, turned left (45 degrees), turned right (45 degrees), tilted left (40 degrees), tilted right (40 degrees), with eyes both opened and closed. The data obtained indicate that wide standard deviations exist in the observed parameters and no significant changes were observed with the head turned either to the right or left nor with the head tilted in either direction. Moreover, the posturographic data obtained with eyes open were slightly reduced in comparison to those obtained with the eyes closed. One can, thus, conclude that neither cervical nor otolithic inputs influence posturographic parameters under static conditions, while visual inputs modify significantly posturographic data, except the coordinates of the foot center of pressure.

Adult↗

PubMedDate not supplied

[Ultrastructural aspects of cholesteatoma of the middle ear].

Middle ear cholesteatomas were intraoperatively obtained from 6 male patients and studied under light (L.M.), transmission (T.E.M.) and scanning (S.E.M.) electron microscopy. Cholesteatoma proved to be formed by keratinizing squamous epithelium, or matrix, and by connective tissue, chorion or perimatrix. With regard to the matrix, a progressive differentiation of cells belonging to the stratum germinativum could be observed towards spinosum, granulosum and corneum cells with formation of keratinized lamellae. Moreover, keratinocytes and Langerhans cells were found in the stratum spinosum. The perimatrix consisted of granulation tissue, or inflamed subepithelial connective tissue displaying inflammatory cells. Furthermore, the advancing front of cholesteatoma proved to be formed by lymphocytes and plasma cells, partially covered by respiratory type epithelium.

Adult↗

PubMedDate not supplied

[Quantitative abnormalities in nystagmus induced by caloric stimulation in multiple sclerosis].

Vestibular nystagmus induced by caloric stimulation (20 degrees and 44 degrees C) was evaluated in terms of duration, frequency and slow phase velocity in 80 patients suffering from clinically defined multiple sclerosis. Criteria of abnormality were established with reference to 3 confidence levels from normative data of a 15-subject control group. Abnormal data representative of vestibular hypo- and hyperreflexia were found ranging between 27 and 53% depending on different parameters and diagnostic criteria. Significant differences in occurrence of nystagmus abnormalities became evident by analyzing 6 different windows of the vestibular response. Different distributions of hypo- and hyperreflexia were observed in relation to the time-course of the normal cumulative response curve, as well as to different stimulus temperatures. For each subject the abnormal data of the 2 stimulated ears X 2 caloric stimulations X 6 analysis windows were cumulated, yielding an overall outcome of pathological results in 66% to 90% of the patients, depending on the different diagnostic criteria.

Adolescent↗

PubMedDate not supplied