Biomedical subjects
Publications and source records attributed to R Charachon.
Cholesteatoma is usually very extensive in children. There are two possible explanations: the speed of tissue growth and the degree of infection and inflammation brought by the Eustachian tube. The cholesteatoma develops rapidly in a pneumatized mastoid which it takes by surprise. All these factors explain the extensive, finger-like shape taken by cholesteatoma in children.
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In 533 surgical procedures for cholesteatoma, a closed technique was used in 60%, an obliteration technique with Palva flap was used in 35%, and an open technique was used in 5%. The closed technique has been done in stages in the authors' institution since 1973. The obliteration technique was only staged if the mesotympanum was dissected. In some cases, the Palva flap was partially lifted from the bone to check posterior cavities. A closed technique in one stage provided intact tympanic membrane in 97% of cases, but retraction pocket occurred in 25%; ABG was within 20 dB in 68% of ears if the stapes was intact and in 40% if crura were missing. Obliteration technique in one stage (if the mesotympanum was normal) provided intact tympanic membrane in 100% of cases, but one late residual cholesteatoma under the flap eroded the semicircular canal after 5 years. ABG within 20 dB was achieved in 68% of the ears if the stapes was intact and in 40% if crura were missing. Closed technique in two stages with Silastic sheeting achieved intact tympanic membrane in 97% of the ears. Residual cholesteatoma was removed at the second stage in 24% of the ears. ABG within 20 dB was achieved in 57% of the ears if stapes was intact and in 52% if crura were missing. Ten percent of the ears underwent an obliteration transformation at the second stage because of large mesotympanum cholesteatoma or retraction pocket. Late retraction pockets were observed in 10% of cases. Obliteration technique in two stages provided an intact tympanic membrane in 96.8% of the ears.(ABSTRACT TRUNCATED AT 250 WORDS)
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Cholesteatomas of the temporal bone are lesions which exceed the classical limitations of cholesteatoma middle ear. Certain raise the problem on their acquired or congenital origin. All require delicate but obligatory surgical treatment using various techniques and approach of oto-neurosurgery. Forty-two cases are studied here, bringing together the series from the Grenoble University Hospital.
6 patients with brainstem infarction and oculomotor signs were studied. One case was consistent with a mesencephalic infarct (internuclear ophthalmoplegia); 4 cases were consistent with a protuberantial infarct (3 cases of "one and a half" syndrome and one case of pontine reticular syndrome associated with a palsy of the root of the VIth nerve. One case was a laterobulbar syndrome. These 6 patients were studied with CT scan and magnetic resonance imaging (MRI CGR Magniscan 5000 with supraconductor magnet of 0.5 Tesla) with T2 weighted images (TR = 2000 ms, TE = 60; 120 ms) in joined section of 9 or 6 mm thickness. The MRI findings were in each case consistent with an infarction. The clinico-topographic correlations are compared with the oculographic findings.
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Before 1982 the suboccipital approach was reserved for neurinomas larger than 2 cm diameter, whereas since that date the translabyrinthine approach has been employed in all cases where no attempt was made to preserve hearing. Of the 85 patients operated upon between 1978 and 1985, 5 were through a supra-petrous approach, 35 a retro-sigmoid approach, 44 a translabyrinthine approach and one by a transotic approach. Translabyrinthine approaches allowed the best postoperative course and conservation of normal facial motility in 22 patients of 33 with stages II and III lesions. An attempt was made to preserve hearing in 9 patients, with one reasonable result by the supra-petrous approach and 2 satisfactory results including one perfect operated upon using a rectosigmoid approach.
Between 1966 and 1981, 141 cholesteatomas were operated upon in children who were 3-15 years old. Radical mastoidectomy was performed in 5 cases. Open cavity tympanoplasty was done in 3 cases. Intact canal wall technique was performed in 99 cases, with a planned second stage in 83 cases (all cholesteatoma cases since 1973). ICWT avoids a large cavity in a well pneumatized mastoid and the second stage controls residual cholesteatomas which were more frequent in children (50%) than in adults (22%). Because of multiple or large residual cholesteatomas, a third stage was performed in 3 cases. Because of a large mesotympanum and/or attic residual cholesteatoma, a transformation of ICWT to an obliteration technique was performed in 4 cases. Retraction pockets were found after the first stage in 12 cases and a transformation of ICWT to an obliteration technique was done in 8 cases at the second stage. Late retraction pockets were found after 5 years in 20% after 2 stages and in 25% after one stage. If a retraction pocket is observed at the second stage, transformation of ICWT to an obliteration technique must be performed. Obliteration technique was performed in 34 cases. A second stage was planned in 26 cases only if the mesotympanum was to be dissected raw. Hearing results were better with an intact stapes (56% of air-bone gap less than or equal to 20 dB).
Clinical features of temporal bone cholesteatoma are miscellaneous, and sometimes misleading: signs of middle ear cholesteatoma, progressive or sudden facial palsy, sensorineural deafness as in acoustic neuroma, conductive deafness as in otosclerosis, secretory otitis media, or intracranial complications. Polytomography is the only way to pinpoint topography and extension. CT scanning is very useful in determining extension. Topography and severity of deafness are the guidelines for surgical approach. Among sixteen cases, total deafness was produced by the lesion itself in ten cases, and six had an intact inner ear; preservation of hearing was possible in only three. Supralabyrinthine cholesteatomas (five cases) are best managed by the middle fossa approach. Infralabyrinthine cholesteatomas (six cases) must be removed via the infratemporal approach with anterior displacement of the tympanic and mastoid segments of the facial nerve and permanent obliteration of the middle ear. Posterior perilabyrinthine cholesteatoma (five cases) may be removed by the otologic approach combined with the middle ear fossa approach if the inner ear is to be preserved. If hearing loss is total, the translabyrinthine approach can be used.
Surgical treatment for fibroadhesive otitis was performed in thirty-seven ears: eight were classified grade 1, with fibrogranulomatous tissue and mucous effusion; twenty-seven were stage 2, with thick fibrogranulomatous tissue without effusion but with cholesterol granuloma. Fifteen ears had small or middle size cholesteatomas, four had posterior retraction pockets. Results obtained were as follow. One stage procedures were usually functional failures in spite of Silastic sheeting, including one tympanoplasty using closed technique with posterior tympanotomy, three dissections of mesotympanum combined with antroatticotomy, and four obliteration procedures in one stage. Better results were obtained with two stage procedures with Silastic sheeting placed at the first stage and removed at the second. Five closed techniques yielded only one good functional result, but seventeen obliteration procedures with Palva flaps yielded the best results: healthy and thin mucosa in fifteen cases, with the mucosa remaining thick in only two cases. Good functional results (air-bone gap less than or equal to 20 dB) were obtained in ten cases, and among them very good functional results (air-bone gap less than or equal to 10 dB) in seven cases. Seven second stages have not yet been done.
The term fibro-adhesive otitis is considered to correspond to filling of the middle ear with fibro-inflammatory tissue with an intact drum. When the fibrous tissue is very thin, that is to say when the mucosa is replaced by malpighian epithelium, the term epidermization or retraction pocket is preferred, this corresponding to different surgical problems, even though the roles of tubal insufficiency and seromucous otitis are probably the same in the etiology of fibro-adhesive otitis and epidermizations of the middle ear. Fibro-adhesive otitis presents as two different stages: a fibro-inflammatory phase in which the middle ear is filled with fibrous tissue and contains cystic spaces full of mucus; a fibro-adhesive phase when the whole middle ear is full of fibrous tissue and contains cholesterol granulomata but no cystic spaces. A study was conducted on 37 ears (8 at the fibro-inflammatory and 29 at the confirmed fibro-adhesive stage). Small cholesteatomas were associated in 15 ears and a posterior retraction pocket in 4. Results were frankly very poor for one-stage operations (exploration of the tympanic cavity with silastic and mastoidectomy (3 cases), tympanoplasty using a closed technique (1 case), and tympanoplasty using an open technique with obliteration (4 cases). Best results were obtained by a two-stage operation with prolonged inclusion of silastic between the two stages.(ABSTRACT TRUNCATED AT 250 WORDS)
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A 12-electrode device has been implanted in the cochlea of a deaf human patient. The electrical impedances have been measured for sine-wave excitation at frequencies ranging from 100 to 3000 Hertz. Based on these results, an equivalent electrical circuit has been designed and its parameters computed. In addition, the patient's perception thresholds for sine-wave pulses at similar frequencies have been measured.