Ferda Akdaş

Prognostic Value of Auditory Brainstem Response for Neurologic Outcome in Patients With Neonatal Indirect Hyperbilirubinemia

To investigate the value of the auditory brainstem response as a reliable test for the neurologic prognosis of infants with neonatal indirect hyperbilirubinemia, auditory brainstem response studies were performed in 22 infants. The patients were followed up until 12 months of age. Two patients demonstrated pathologic auditory brainstem response consistent with auditory neuropathy but had no neurologic finding except a lack of speech at 12 months of age. Two other patients had neurologic sequelae, one showing severe dyskinetic cerebral palsy, the other mild hypotonia and motor retardation, but their auditory brainstem response results were normal. These results suggested that auditory brainstem response examination might not provide reliable information for the neurologic prognosis. Neurologic disturbances resulting from bilirubin neurotoxicity can be seen in patients with a normal auditory brainstem response, but patients with an abnormal auditory brainstem response may not have any neurologic dysfunction apart from speech retardation. (J Child NeuroL 2001;16:772-775).

Noise levels in neonatal intensive care unit and use of sound absorbing panel in the isolette

OBJECTIVE The purposes of this study were to measure the noise level of a busy neonatal intensive care unit (NICU) and to determine the effect of sound absorbing panel (SAP) on the level of noise inside the isolette. METHODS The sound pressure levels (SPL) of background noise, baby crying, alarms and closing of isolettes door/portholes were measured by a 2235-Brüel&Kjaer Sound Level Meter. Readings were repeated after applying SAP (3D pyramidal shaped open cell polyurethane foam) to the three lateral walls and ceiling of the isolette. RESULTS The median SPL of background noise inside the NICU was 56dBA and it decreased to 47dBA inside the isolette. The median SPL of monitor alarms and baby crying inside the isolette were not different than SPL measured under radiant warmer (p>0.05). With SAP, the median SPL of temperature alarm inside the isolette decreased significantly from 82 to 72dBA, monitor alarm from 64 to 56dBA, porthole closing from 81 to 74dBA, and isolette door closing from 80 to 68dBA (p<0.01). There was a significant reduction in the noise produced by baby crying when SAP was used in the isolette (79dBA vs 69dBA, respectively) (p<0.0001). There was also significant attenuation effect of panel on the environmental noise. CONCLUSIONS The noise level in our NICU is significantly above the universally recommended levels. Being inside the isolette protects infants from noise sources produced outside the isolette. However, very high noises are produced inside the isolette as well. Sound absorbing panel can be a simple solution and it attenuated the noise levels inside the isolette.

Protective role of resveratrol against cisplatin induced ototoxicity in guinea pigs

OBJECTIVE The aim of this study was to evaluate the effectiveness of systemic administration of resveratrol against cisplatin-induced ototoxicity in guinea pigs. MATERIALS AND METHODS Healthy guinea pigs (n=24) were randomly divided into four groups. Group 1 (n=6) received resveratrol+cisplatin, group 2 (n=6) received 4% ethanol+cisplatin, group 3 (n=6) received cisplatin, and group 4 (n=6) received saline. Cisplatin was administered at a dose of 10mg/kg/day on days 14 and 15 of the study. Resveratrol (10mg/kg/day), 4% ethanol, and saline were administered throughout the study. Baseline auditory brainstem responses (ABR) (4 kHz, 8 kHz, and click stimulus) were determined for all groups. ABR was repeated 72 h after the last dose of cisplatin in order to record the threshold shifts. The ABR threshold shifts for the click stimulus, 4-kHz- and 8-kHz-frequency stimuli were compared after drug administration. After follow-up ABRs the animals sacrificed under deep sedation and their cochleae were removed. Left cochleae were immediately harvested for measurement of level of reactive oxygen species (ROS). Right cochleae were prepared for histological changes which were observed by scanning electron microscopy (SEM). RESULTS For the all stimulus, there was a significant threshold difference among the groups (p<0.01). Group 3 had a significantly higher threshold shift at all stimuli when compared with groups 1 and 4. There was no significant threshold shifts in all stimuli between groups 2 and 3. The resveratrol-treated group 1 showed preservation of threshold in ABR (p ≤ 0.05). SEM showed that inner and outer hair cells were preserved in the group 1. Level of reactive oxygen species (ROS) were significantly higher in groups 2 and 3 compared with groups 1 and 4 (p ≤ 0.05). CONCLUSION These results indicated that systemic administration of resveratrol afforded statistically significant protection to the cochlea of guinea pigs from cisplatin toxicity. Experimental dose of resveratrol injections may have a protective effect against cisplatin ototoxicity in guinea pigs.

Ototoxic Effect of Burow Solution Applied to the Guinea Pig Middle Ear

Objective: To analyze the ototoxicity of Burow solution as an otologic preparation. Background: Burow solution has been used for years in the treatment of acute or chronic otitis externa and chronic suppurative otitis media. This acidic solution has antibacterial and antiedematous properties. Ototoxic effect of Burow solution has not been known, so the current study was designed to observe the ototoxic effect of Burow solution experimentally. Materials and Methods: Experiments were performed in 32 young, male albino guinea pigs (weight, 450-550 g). Twenty animals in the experimental group were divided into 2 groups of 10 animals each. The first group received 13% Burow solution (13% aluminum subacetate), and the second received 4% Burow solution (4% aluminum subacetate). Twelve animals in the control group were divided into 2 groups of 6 animals each. The first group received gentamicin (40 mg/mL; ototoxic control), and the second received saline solution (negative control). Under general anesthesia, pretreatment auditory brainstem responses (ABRs) from the right ear were obtained from the animals in all groups. The right tympanic membranes were widely perforated, and a small piece of Gelfoam was applied to the middle ear. Ear solutions at concentrations of 0.1 mL were applied through transcanal approach to the middle ear twice a day in 10 days. Under general anesthesia, the Gelfoam was removed from the right middle ear, and posttreatment ABRs were obtained 14 days later after the initial time in all groups. Results: Baseline ABR results were normal in right ears of all animals tested. Animals undergoing placement of Gelfoam with either 13% Burow solution, 4% Burow solution, or saline in the middle ear showed no changes in ABR threshold. The gentamicin group showed significant change in the ABR threshold. Conclusion: Burow solution was considered to be an effective and safe otologic preparation.

Auditory neuropathy in hyperbilirubinemia: is there a correlation between serum bilirubin, neuron-specific enolase levels and auditory neuropathy?

This study evaluated whether a correlation exists between increased serum bilirubin and neuron-specific enolase (NSE) assays (a biochemical index of neuronal damage) and auditory neuropathy. Nineteen term neonates without hemolysis whose serum bilirubin levels were above 20 mg/dl and 27 healthy term newborns with bilirubin levels <13 mg/dl were included in the study. Auditory brainstem responses (ABRs) and transient evoked otoacoustic emissions (TEOAEs) of patients with hyperbilirubinemia were obtained before discharge. This preliminary study did not show any correlation between the serum NSE and bilirubin values. However, infants who had auditory neuropathy had significantly higher NSE levels, and thus these patients, being in the high-risk group, need close follow-up. Sumario Este estudio evala cu ndo existe una correlacin entre la bilirrubina s rica aumentada y los niveles neuronaespecficos de enolasa (NSE) (un índice bioqumico de da o neuronal) con la neuropata auditiva. Diez y nueve neonatos a t rmino sin hemlisis, cuya bilirrubina s rica estuvo por arriba de 20 mg/dl y 27 neonatos de trmino sanos, con niveles de bilirrubina de <13 mg/dl, se incluyeron en este estudio. Las respuestas auditivas del tallo cerebral (ABRs) y las emisiones otoac sticas evocadas por transitorios (TEOAEs) de los pacientes con hiperbilirrubinemia se obtuvieron despus del alta hospitalaria. Este estudio preliminar no mostró ninguna correlacin entre la NSE en suero y los valores de bilirrubina. No obstante, los ni os que tuvieron neuropata auditiva presentaron niveles NSE significativamente mayores por lo que esos pacientes, estando en el grupo de alto riesgo, requieren un seguimiento m s cercano.

Effects of Topical Otic Preparations on Hearing in Chronic Otitis Media

Most of the topical otic preparations have been shown to cause ototoxicity. In this study ciprofloxacin hydrochloride, a relatively new topical agent, and gentamicin sulfate were studied in two groups of 20 patients with chronic otitis media. Patients were randomly selected to receive either ciprofloxacin (200 μg/ml) or gentamicin sulfate (5 mg/ml) locally, five drops three times a day for 10 days. Clinical response was seen in 20 of 20 patients in the ciprofloxacin group compared with 6 of 20 patients in the gentamicin group. Audiometric evaluation revealed no significant ototoxic effect in either group. In fact, hearing thresholds were slightly better than pretreatment levels in both groups.

Ototoxic effect of topical ciclopirox as an antimycotic preparation.

To evaluate the ototoxicity of ciclopirox-containing solution as an otologic preparation for the treatment of otomycosis. Background: Ciclopirox is a synthetic antimycotic agent available in a variety of formulations to treat superficial fungal infections. Ciclopirox has demonstrated both fungicidal and fungistatic activity in vitro against a broad spectrum of pathogenic fungi. It also possesses a broad-spectrum antibacterial properties, anti-inflammatory, and antiedema effect. The ototoxic effect of ciclopirox-containing solutions has not been known, so the current study was designed to observe the ototoxic effect of this solution experimentally. Materials and Methods: Experiments were performed in 22 young male albino guinea pigs (weight, 450-550 g). The 10 animals in the experimental group received ciclopirox solution, and the control group was divided into two groups of six animals each. The first group received saline solution (negative control) and the second received gentamicin (40 mg/mL; ototoxic control). Under general anesthesia, pretreatment auditory brainstem responses (ABRs) from the right ears were obtained from the animals in all groups. The right tympanic membranes were totally perforated, and a small piece of Gelfoam was applied to the middle ear directly to the round window membrane. Ear solutions were applied through transcanal approach to the middle ear twice a day in 2 weeks. Twenty-two animals of perforated tympanic membrane were observed during a 2-week period. Posttreatment ABRs were obtained in all groups in a week after the last administration. Results: Baseline ABR results were normal in right ears of all animals tested. Animals undergoing placement of Gelfoam with either ciclopirox solution or saline in the middle ear showed no changes in the ABR threshold. The gentamicin group showed a significant change in the ABR threshold. Conclusion: In the guinea pig, when applied topically to the middle ear, ciclopirox does not cause a reduction in the ABR threshold. Because its safety has not yet been confirmed in patients, caution should be observed when prescribing this agent.

Cochlear implantation in patients with bilateral cochlear trauma

PURPOSE Temporal bone fracture, which involves the otic capsule, can lead to complete loss of auditory and vestibular functions, whereas the patients without fractures may experience profound sensorineural hearing loss due to cochlear concussion. Cochlear implant is indicated in profound sensorineural hearing loss due to cochlear trauma but who still have an intact auditory nerve. MATERIAL AND METHODS This is a retrospective review study. We report 5 cases of postlingually deafened patients caused by cochlear trauma, who underwent cochlear implantation. Preoperative and postoperative hearing performance will be presented. These patients are cochlear implanted after the cochlear trauma in our department between 2001 and 2006. RESULTS All patients performed very well with their implants, obtained open-set speech understanding. They all became good telephone users after implantation. Their performance in speech understanding was comparable to standard postlingual adult patients implanted. CONCLUSION Cochlear implantation is an effective aural rehabilitation in profound sensorineural hearing loss caused by temporal bone trauma. Preoperative temporal bone computed tomography, magnetic resonance imaging, and promontorium stimulation testing are necessary to make decision for the surgery and to determine the side to be implanted. Surgery could be challenging and complicated because of anatomical irregularity. Moreover, fibrosis and partial or total ossification within the cochlea must be expected.

Clinical Characteristics and Prognostic Factors in Childhood Bacterial Meningitis: A Multicenter Study

OBJECTIVE To evaluate clinical features and sequela in children with acute bacterial meningitis (ABM). STUDY DESIGN Multicenter retrospective study. MATERIAL AND METHODS Study includes retrospective chart review of children hospitalised with ABM at 11 hospitals in İstanbul during 2005. Follow up visits were conducted for neurologic examination, hearing evaluation and neurodevelopmental tests. RESULTS Two hundred and eighty three children were included in the study. Median age was 12 months and 68.6% of patients were male. Almost all patients had fever at presentation (97%). Patients younger than 6 months tended to present with feeding difficulties (84%), while patients older than 24 months were more likely to present with vomitting (93%) and meningeal signs (84%). Seizures were present in 65 (23%) patients. 26% of patients were determined to have at least one major sequela. The most common sequelae were speech or language problems (14.5%). 6 patients were severely disabled because of meningitis. Presence of focal neurologic signs at presentation and turbid cerebrospinal fluid appearance increased sequelae significantly. Childen under 24 months of age developed neurologic sequelae more commonly than older children. CONCLUSION Symptoms and signs were largely depending on the age of the patient. Speech or language problems were the most common sequelae following meningitis.

Cochlear implantation: is hearing preservation necessary in severe to profound hearing loss?

Objectives: The goal of the cochlear implant surgery is to place the electrode array with minimal damage to preserve the residual hearing. Round-window insertion can be performed in a manner that is potentially less traumatic than the standard cochleostomy. The purpose of the study was to investigate audiological results of the round-window approach using standard electrode. Methods: A retrospective study was performed to evaluate our experience in patients with implanted through round window between January 2007 and March 2009. Sixty patients had undergone cochlear implant surgery through the round window with full insertion of a standard electrode array. Preoperative and postoperative pure-tone thresholds were measured for implanted ears in the range of 250 to 4000 Hz. Results: Within these 60 cases, 31 patients had been evaluated. The population comprised 16 women and 15 men. The mean age was 15.96 years (range, 4-64 years). Follow-up times ranged from 6 to 26 months. Preservation of low-frequency hearing (250 and 500 Hz) was achieved in 27 (87%) of 31 patients. Complete hearing preservation (all frequencies) was accomplished in 11 patients (35.48%). No hearing could be determined postoperatively in 4 patients (12.9%), having preoperative thresholds of 120 dB at 250, 500, and 1000 Hz. Conclusions: Round-window approach has been widely used for preservation of residual hearing. In our patients with severe to profound hearing loss, we preserved residual hearing. Although the residual hearing cannot be sufficient for using additional acoustic stimulation, the preserved residual hearing means minimal damage and a more convenient cochlea, so this is promising for future development.