Biomedical subjects

N Marangos

Publications and source records attributed to N Marangos.

45 records · Page 3Linked to original sources

PubMed1995

[High resolution computerized tomography of the petrous bones in a bone algorithm and 2D reconstruction for evaluation of the facial nerve canal].

Radiographic imaging of the intratemporal portion of the fallopian canal is important in cases of traumatic facial nerve palsy to visualize the site of involvement. Even if high-resolution computed tomography is used, several images in various planes are necessary to obtain satisfactory diagnostic information. By using a classic axial scan and a wide window (bone algorithm), a 2D reconstruction can be performed "off-line" to visualize the mastoid portion of the fallopian canal. A reconstruction plane 45 degrees to the median-sagittal plane and through the lateral genu of the facial nerve provides the best imaging of the mastoid portion down to the stylomastoid foramen. In cases of temporal bone fractures with facial paralysis, an excellent demonstration of fracture line without further radiation exposure can be obtained in cases considered for surgical decompression.

Adult↗

PubMed1994

[Implantation on the cochlear nucleus. Apropos of a patient with bilateral neuroma].

A new auditory brainstem implant (ABI), manufactured by Cochlear, was implanted in a young patient suffering from a large bilateral acoustic neuroma, associated with multiple other tumors due to a tuberor sclerosis of Bourneville. The operating procedure and the first results are described. A short historical summary, the anatomical basis and the difficulties due to side effects of stimulation are exposed.

Adult↗

PubMed1992

Diagnostic value of transtympanic electrocochleography; case reports.

The transtympanic electrocochleography is performed on more than 1000 patients with various hearing loss. The registration technique in brief as well as some interesting findings (endolymphatic hydrops, neural hearing loss due to multiple sclerosis, mitochondrial cytopathology) will be presented. The indications of the electrocochleography as an audiological topo-diagnostic tool will be discussed.

Adult↗

PubMed1990

[Dehydration therapy in low tone hearing loss. An alternative to rheologic therapy?].

Patients with acute low-tone sensorineural hearing loss were treated by rheology or dehydration after recording of the summation and compound action potentials by electrocochleography. Patients treated in the acute phase, as well as patients with chronic disease (that is the interval between onset of hearing loss and therapy was more than 1 week) clearly responded better to dehydration than to conventional rheological treatment. This was especially striking in those patients showing an enhanced SP/AP ratio indicating endolymphatic hydrops.

Acetazolamide↗

PubMed1990

[Audiologic diagnosis of tumor-induced neural hearing disorders based on discrete finding constellations].

Modern electrophysiological and audiometric tests allow the cause of retrocochlear hearing loss to be diagnosed in almost all cases. Assessment of the stapedius reflex, discrimination using the Fowler test, the ERA findings with respect to inter-peak latency, interaural latency difference of the fifth wave, DORAS (difference between the objective response threshold and the subjective tone threshold), and finally the vestibular findings are all important.

Adult↗

PubMed1990

[Familial neural mitochondrial deafness].

Mitochondrial abnormalities are known to cause several neurological syndromes that often include hearing loss as one of their features. We present two brothers with mitochondrial cytopathy and hearing loss. The audiological and electrocochleographic findings suggest a neural origin for the hearing impairment. Muscle biopsy is an important tool for the diagnosis of these syndromes in patients with audiological evidence of a bilateral neural hearing loss and neurological abnormalities.

Adult↗

PubMed1990

[Electrocochleography possibilities in the differential diagnosis of hydrops and neural hearing loss].

Enhancement of the click-evoked summating potential causing a pathological summation to compound action potential ratio (SP/CAP) in patients with endolymphatic hydrops has been described by several groups. An increased SP/CAP ratio is found also in some patients with a tumour of the cerebellopontine angle. The study of further parameters of the SP/CAP complex, such as the CAP latency and the width of the complex, permit an electrocochleographic differentiation between both forms of hearing loss. The N2 amplitude showed no diagnostic significance.

Audiometry, Evoked Response↗

PubMed1989

[Unusual electrocochleography cases].

The electrocochleographic findings of 3 unusual cases from about 350 performed on patients with various hearing loss are presented; they demonstrate the value of electrocochleography as a clinical tool in otological investigation. The first case was an electrocochleographically detected acute impairment of the first neuron, the second a hereditary hearing loss with endolymphatic hydrops, and the last shows the effect of an endolymphatic shunt on a hydropic hearing loss.

Adult↗

PubMed1989

[Frequency-dependent cochlear microphonics in inner ear hearing loss with various pitch thresholds].

Promontory recordings of the cochlear microphonics (CM) after stimulation with 0.5, 1 and 2 kHz tone bursts at 120 dB SPL were performed on normal subjects and patients with various, levels of sensory hearing loss. A significant correlation was found between frequency-related CM amplitudes and the configuration of the pure-tone audiogram. Such recordings provide objective information on hearing abilities at low and middle frequencies and are thus a relevant tool in clinical audiometry.

Auditory Threshold↗