Biomedical subjects

I Psarommatis

Publications and source records attributed to I Psarommatis.

7 recordsLinked to original sources

PubMed2006

Neurotoxicity of vincristine on the medial olivocochlear bundle.

OBJECTIVE: Vincristine is a well known neurotoxic chemotherapeutic agent. Dose dependent and cumulative peripheral neuropathy is the main dose limiting side effect of chemotherapy with vincristine. The mechanisms responsible for the neurotoxic effects of vincristine have not yet been fully understood. This prospective study was directed at determining whether vincristine treatment interferes with the function of the medial olivocochlear bundle. DESIGN: Fifteen children suffering from leukemia were subjected to tympanogram, stapedial muscle reflex, pure tone audiometry and transient evoked otoacoustic emissions (TEOAEs) in the absence and presence of contralateral white noise on day 1 and on day 22 of treatment with vincristine. The function of the medial olivocochlear bundle was assessed by the phenomenon of suppression of otoacoustic emissions by contralateral application of white noise. RESULTS: The study revealed a statistically significant decrease of contralateral suppression amplitudes in all cases after three sessions of chemotherapy with vincristine. On the contrary no alterations were observed in pure tone audiometry thresholds. A non-significant decrease of the mean TEOAEs' amplitudes was also noted. When analyzed by frequency, however, this decrease reached the level of statistical significance at two frequencies. CONCLUSION: Vincristine treatment seems to exert a neurotoxic effect on the efferent olivocochlear system, which takes place early in the course of chemotherapy. This is a new aspect to be added to the possible mechanisms underlying the toxicity of vincristine in the auditory periphery. Whether changes in efferent function might contribute to understanding the mechanisms of neurotoxicity caused by vincristine, or find any clinical application as a predictor or early detector of neurological side effects of vincristine still remains to be seen.

Acoustic Stimulation↗

PubMed2005

The effect of treatment with vincristine on transient evoked and distortion product otoacoustic emissions.

OBJECTIVE: Vincristine chemotherapy is mainly associated with neurotoxic effects. The ototoxicity of vincristine has been related to high dosage, while low and moderate doses do not seem to induce significant hearing impairment when measured by pure tone or speech audiometry. Otoacoustic emissions have been reported to be more sensitive in early detection of ototoxicity than conventional pure tone audiometry. The present study was directed at determining whether vincristine treatment interferes with outer hair cell function in the absence of measurable changes in pure tone audiometry. METHODS: We studied prospectively a cohort of ten children suffering from leukemia. All children were subjected to tympanogram, stapedial muscle reflex, pure tone audiometry, transient evoked (TEOAEs) and distortion product (DPOAEs) otoacoustic emissions on day 1 and on day 22 of treatment with vincristine. TEOAEs were analyzed in terms of emission level and reproducibility as a function of frequency. DPOAEs were obtained as DP-grams and were analyzed in terms of amplitude. RESULTS: The analyzed parameters of TEOAEs and DPOAEs revealed a declining tendency, although changes did not reach statistical significance. Pure tone audiometry and stapedial reflex thresholds were not altered. CONCLUSION: For the population of this study, vincristine did not seem to cause significant alterations of otoacoustic emissions' recordings and consequently significant outer hair cell damage.

Acoustic Impedance Tests↗

PubMed2005

Etiological diagnosis of bilateral, sensorineural hearing impairment in a pediatric Greek population.

Early diagnosis, evaluation and treatment of childhood deafness are essential for a child's normal growth. Etiological diagnosis of hearing loss makes prevention, family scheduling and more effective therapy feasible goals. Etiological assessment of sensorineural deafness still remains difficult although recently with the progress of genetics it has become more efficient. In this retrospective study, the etiology of bilateral, sensorineural hearing loss with indication for hearing aids has been studied in 153 hearing impaired children. Etiological diagnosis was based on family and patient record, physical, audiological and laboratory examinations. Among the 94 children who completed the diagnostic protocol etiological groups revealed the following distribution: non-hereditary acquired hearing impairment was present in 36 children (38%) and hereditary was present in 44 (47%) children. The etiology remained unknown in 14 (15%) children. Non-syndromic autosomal dominant type accounted for 13 (29% of hereditary hearing loss) children, non-syndromic autosomal recessive type for 21 (48%) children and syndromic deafness for 10 (23%) children. Modern diagnostic methods, such as genetic testing, help diminish the number of cases with hearing impairment of unknown etiology, for the benefit of children who receive early and appropriate medical, audiologic, genetic and educational counseling based on the etiology of their hearing loss.

Child↗

PubMed2001

Hearing evaluation with distortion-product otoacoustic emissions in young patients undergoing haemodialysis.

Sensorineural hearing loss is frequently reported in young patients with chronic renal failure having haemodialysis. The effect of a single session of haemodialysis on hearing acuity was assessed prospectively in nine children with end-stage renal disease using pure-tone audiometry (PTA) and distortion-product otoacoustic emissions (DPOAEs). Results were compared with those obtained from nine audiologically normal healthy children also tested with PTA and DPOAEs twice during a 4-h interval. Sensorineural hearing loss of unknown aetiology was found in 55.5% of renal patients, mainly in the higher frequencies. Patients on HD had mean PTA thresholds significantly poorer than those of the control group in the frequency range 1000-12 000Hz (P < 0.05). Their mean DPOAE amplitudes were significantly lower in all frequencies > 1184 Hz (P < 0.05). Furthermore, patients' ears with normal PTA thresholds between 250 and 4000 Hz also had decreased DPOAE amplitudes. No significant changes in PTA thresholds or DPOAE amplitudes were encountered in renal patients before and after a HD session (P > 0.05). Changes in PTA thresholds or DPOAE amplitudes were not significantly different than those in the control group (P > 0.05). In conclusion, sensorineural hearing loss of unknown origin, especially in high frequencies, is frequent in young renal patients under HD and single HD sessions do not seem to alter the hearing acuity of these patients. DPOAEs seem to be more sensitive to incipient cochlear damage than behaviour thresholds in monitoring renal patients.

Adolescent↗

PubMed2001

Isolated inverted papilloma of the sphenoid sinus.

Inverted papilloma is a rare benign sinonasal tumour, characterized by a potentially invasive nature. The lateral nasal wall represents the most common site of origin, whereas paranasal sinuses are quite frequently found to be involved by extension. In contrast, primary sinus inverted papillomas have rarely been reported. The present study describes an extremely rare case of inverted papilloma, isolated to the left sphenoid sinus, that was treated by a transnasal endoscopic procedure. The therapeutic approach chosen is discussed and the results of a two-year follow-up are also presented.

Endoscopy↗

PubMed1997

Isolated sphenoid sinus aspergillomas.

Fungi are more often than previously believed to be the causative organisms of paranasal sinusitis. Aspergillus, a fungus belonging to the Ascomycetes class, accounts for the majority of these infections, which affect not only debilitated patients but healthy people as well. There are two distinct clinical forms of Aspergillus sinusitis, invasive and non-invasive, and each of them is further divided in two subtypes. Isolated aspergillosis of the sphenoid sinus is a rare disease, which is usually misdiagnosed for a long time because of its varying symptomatology. In the present study, four cases of isolated sphenoid Aspergillus disease are described and the recent literature is reviewed. Physicians should be aware of this rare clinical entity, as in many cases early diagnosis and appropriate treatment provide the key to achieve favourable outcomes.

Adult↗

PubMedDate not supplied

Multiple-frequency tympanometry in children with otitis media with effusion.

Multifrequency tympanograms were recorded from 76 ears of 43 children affected by otitis media with effusion (OME) and 90 ears of normal-hearing children to obtain data for resonance frequency (RF) and changes in phase angle. There was found to be a statistically significant decrease (p < 0.01) in both RF values and change in phase angle in ears with OME compared to normative data. This decrease may be interpreted by considering OME as a mass pathology. Multiple-frequency tympanometry seems to be a useful method for determining the effect of various middle-ear pathologies on the mechano-acoustical status of the middle-ear system.

Acoustic Impedance Tests↗