Flat Panel Angiography in the Cross-Sectional Imaging of the Temporal Bone: Assessment of Image Quality and Radiation Dose Compared with a 64-Section Multisection CT Scanner.

BACKGROUND AND PURPOSE: Cross-sectional imaging of the temporal bone is challenging because of the complexity and small dimensions of the anatomic structures. We evaluated the role of flat panel angiography in the cross-sectional imaging of the temporal bone by comparing its image quality and radiation dose with a 64-section multisection CT scanner. MATERIALS AND METHODS: We retrospectively collected 29 multisection CT and 29 flat panel angiography images of normal whole-head temporal bones. Image quality was assessed by 2 neuroradiologists, who rated the visualization of 30 anatomic structures with a 3-point ordinal scale. The radiation dose was assessed with an anthropomorphic phantom. RESULTS: Flat panel angiography showed better image quality than multisection CT in depicting the anterior and posterior crura of the stapes, the footplate of the stapes, the stapedius muscle, and the anterior ligament of the malleus (P < .05). In contrast, multisection CT showed better image quality than flat panel angiography in assessing the tympanic membrane, the bone marrow of the malleus and incus, the tendon of the tensor tympani, the interscalar septum, and the modiolus of the cochlea (P < .05). Flat panel angiography had a significantly higher overall image quality rating than multisection CT (P = .035). A reduction of the effective dose of approximately 40% was demonstrated for flat panel angiography compared with multisection CT. CONCLUSIONS: Flat panel angiography shows strengths and weaknesses compared with multisection CT. It is more susceptible to artifacts, but due to the higher spatial resolution, it shows equal or higher image quality in assessing some bony structures of diagnostic interest. The lower radiation dose is an additional advantage of flat panel angiography.

[The use of speech audiometry in the practice of the geriatric center].

The aim of the study was to evaluate a new test of speech audiometry while examining aged patients. 32 aged listeners from 60 to 88 years old were examined: 20 hearing aid (HA) users and 12 patients with normal hearing thresholds and mild cognitive impairment according to the results of the mini-mental state examination (MMSE). The speech audiometry consisted of the traditional polysyllabic words discrimination test and a new speech test with motor responses (Verbal Tasks and Motor Responses - VTMR); in both tests the signal was presented in background noise (polyphony) in free field. All listeners performed the VTMR test significantly better than the polysyllabic words discrimination test. In the group of hearing impaired patients the mean result in VTMR test was 73,2±29,2 % without HA and 88,6±20,5 % with it, in traditional test - 34,8±20,9 % without HA and 56±18,4 % with it. All patients of the group with normal hearing and mild cognitive impairment performed the VTMR test with 100 % result, their speech discrimination score in traditional test was 88±12 %. In the practice of the geriatric center the use of both the traditional speech audiometry and the new speech test with motor responses seems to be reasonable, that allows examining the auditory function in patients with significant deterioration of speech intelligibility or cognitive impairment.

Nimodipine in otolaryngology: from past evidence to clinical perspectives.

As L-type voltage-gated calcium channels (VGCCs) control Ca(2+) influx and depolarisation of cardiac and vascular smooth muscle, they represent a specific therapeutic target for calcium channel blockers (CCBs), which are approved and widely used to treat hypertension, myocardial ischaemia and arrhythmias. L-type currents also play a role in calcium entry in the sensory cells of the inner ear. In hair cells of both cochlea and labyrinth, calcium cytoplasmic influx is the first physiological process that activates complex intracellular enzymatic reactions resulting in neurotransmitter release. Excessive calcium ion entry into sensory cells, as a consequence of L-VGCCs malfunction is responsible for over-activation of phospholipase A2 and C, protein kinase II and C, nitric oxide synthase and both endonucleases and depolymerases, which can cause membrane damage and cellular death if the cytoplasmic buffering capacity is overcome. Nimodipine, a highly lipophilic 1-4 dihydropyridine that easily crosses the brain-blood barrier, is generally used to reduce the severity of neurological deficits resulting from vasospasm in patients with subarachnoid haemorrhage. Moreover, due to its selective blocking activity on L-channel calcium currents, nimodipine is also suggested to be an effective countermeasure for cochlear and vestibular dysfunctions known as channelopathies. Indeed, experimental data in amphibians and mammalians indicate that nimodipine has a stronger efficacy than other CCBs (aminopyridine, nifedipine) on voltage-dependent whole-cell currents within hair cells at rest and it is the only agent that is also effective during their mechanically induced depolarisation. In humans, the efficacy of nimodipine is documented in the medical management of peripheral vestibular vertigo, sensorineural hearing loss and tinnitus, even in a pathology as complex as Ménière's disease. Nimodipine is also considered useful in the prophylaxis of damage to the facial and cochlear nerves caused by ablative surgery of cerebellopontine tumours; it has been recently hypothesised to accelerate functional recovery of recurrent nerve lesions during thyroid cancer surgery. Further trials with adequate study design are needed to test the efficacy of nimodipine in the treatment of vertigo due to cerebrovascular disease and vestibular migraine.

Nickel earlobe dermatitis and clinical non-relevance of the oral exposure.

OBJECTIVE: Nickel is the most common cause of allergic contact dermatitis (ACD). Because nickel restriction is commonly imposed on many patients with the only earlobe ACD to nickel hypersensitivity, the aim of this study was to identify the role of occasional and extended oral nickel exposure in these patients. DESIGN: This is a case-control study. SUBJECTS: Thirty-four outpatients, previously diagnosed as monosensitized to nickel, suffering from earlobe dermatitis were enrolled; 11 of them showed active dermatitis. The control group consisted of six healthy (non-nickel-sensitive) subjects. INTERVENTIONS: High oral nickel challenge (20 mg) and protracted oral challenge (1 mg once a day). Observation period: 6 weeks. RESULTS: Clinical earlobe lesions were not affected by a high oral nickel intake nor by a protracted oral challenge. CONCLUSIONS: Dietary nickel restriction seems to be useless in patients with earlobe ACD due to nickel hypersensitivity.

Auditory cortical responses in patients with cochlear implants.

Currently, the most commonly used electrophysiological tests for cochlear implant evaluation are Averaged Electrical Voltages (AEV), Electrical Advisory Brainstem Responses (EABR) and Neural Response Telemetry (NRT). The present paper focuses on the study of acoustic auditory cortical responses, or slow vertex responses, which are not widely used due to the difficulty in recording, especially in young children. Aims of this study were validation of slow vertex responses and their possible applications in monitoring postimplant results, particularly restoration of hearing and auditory maturation. In practice, the use of tone-bursts, also through hearing aids or cochlear implants, as in slow vertex responses, allows many more frequencies to be investigated and louder intensities to be reached than with other tests based on a click as stimulus. Study design focused on latencies of N1 and P2 slow vertex response peaks in cochlear implants. The study population comprised 45 implant recipients (aged 2 to 70 years), divided into 5 different homogeneous groups according to chronological age, age at onset of deafness, and age at implantation. For each subject, slow vertex responses and free-field auditory responses (PTAS) were recorded for tone-bursts at 500 and 2000 Hz before cochlear implant surgery (using hearing aid amplification) and during scheduled sessions at 3rd and 12th month after implant activation. Results showed that N1 and P2 latencies decreased in all groups starting from 3rd through 12th month after activation. Subjects implanted before school age or at least before age 8 yrs showed the widest latency changes. All subjects showed a reduction in the gap between subjective thresholds (obtained with free field auditory responses) and objective thresholds (obtained with slow vertex responses), obtained in presurgery stage and after cochlear implant. In conclusion, a natural evolution of neurophysiological cortical activities of the auditory pathway, over time, was found especially in young children with prelingual deafness and implanted in preschool age. Cochlear implantation appears to provide hearing restoration, demonstrated by the sharp reduction of the gap between subjective free field auditory responses and slow vertex responses threshold obtained with hearing aids vs. cochlear implant.