Biomedical subjects

R Charachon

Publications and source records attributed to R Charachon.

At least 19 recordsLinked to original sources

PubMed1995

Coexistence of plasma cell granulomas of lung and central nervous system.

A rare case of concurrent plasma cell granulomas (PCG) of the lung and the central nervous system (CNS) is reported. A 30-year-old man was presented with recurrent left headaches lasting for two years. Computerized tomographic (CT) scan and magnetic resonance imaging (MRI) of the head disclosed a process extending from the lateral aspect of the left cavernous sinus to the tentorium cerebelli and the infratemporal fossa through the foramen ovale. At the same time, chest-X ray and CT scan showed three symptomless masses of the pulmonary right lower lobe. Histological examination of cerebral samples and of one of the pulmonary nodules revealed the presence of a fibrous tissue containing numerous lymphocytes and plasma cells as well as remnants of vascular and respiratory structures. Immunohistochemical study proved these cells to be polyclonal. Ultrastructural analysis confirmed the presence of lymphoid cells and failed to disclose any argument for meningioma or histiocytosis X. The differential diagnostic problems of PCG are discussed as well as considerations about clinicopathological features, histogenesis and pathogenesis of inflammatory pseudotumours (IPT).

Adult↗

PubMed1995

Immunohistochemical detection of p53 protein in preneoplastic lesions and squamous cell carcinoma of the head and neck.

Alterations in the p53 tumor suppressor gene are the most frequent genetic abnormalities in human cancers. The p53 protein is present in normal cells, and is assumed to induce G1 arrest or apoptosis in the presence of DNA lesion. The mutant protein lacks this property. Squamous cell carcinomas of the head and neck (SCCHN) are related to carcinogens in tobacco and alcohol, and provide a good model of multiple-step carcinogenesis in association with DNA damage and p53-related tumorigenesis. Stabilization of the mutant p53 protein allows immunohistochemical analyses (IHC) to be routinely used to demonstrate the mutant p53 protein in tissue samples, whereas normal p53 protein is undetectable. Ninety-nine squamous cell carcinomas, 8 in situ carcinomas, 31 preneoplastic lesions and 79 normal carcinogen-exposed mucosas of the head and neck from a total of 107 patients were examined for the expression of p53 tumor suppressor gene protein. Samples were collected before treatment, and stained with p53 specific mono- and polyclonal antibodies (DO-7, Pab 1801 and 240, CM1) using an indirect immunoperoxidase technique. Proliferating cell nuclear antigen (PCNA) provided semiquantitative estimates of proliferation. The main localizations were the pharynx (64/107) and the larynx (21/107). Positive IHC detection of p53 was observed in 9% of normal-appearing carcinogen-exposed mucosas, 37% of hyperplasias, 68% of dysplasias, 75% of in situ carcinomas, and 56/99 (56.5%) of primary tumor samples. Mucosas from 15 control patients under 10 years of age were negative. There was no correlation between p53 IHC and localization, differentiation or TNM staging.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

Nucleus 20-channel and 21-channel auditory brain stem implants: first European experiences.

Central electrical stimulation of the auditory pathway can allow hearing in patients suffering from deafness localized in the auditory nerve. Developments in a multichannel auditory brain stem implant based on the Nucleus Mini 22 cochlear implant with transcutaneous signal transmission is discussed. The device has been implanted in seven European patients who suffered from neurofibromatosis type 2. Preliminary speech perception results and patient satisfaction are encouraging, and the data presented include some limited open-set speech recognition.

Auditory Threshold↗

PubMed1994

[Benign paroxysmal positional vertigo. Apropos of 51 cases].

51 cases of benign paroxysmal vertigo have been investigated in 3 years. The findings put in evidence: the particular frequency of this pathology (18% of BPPV in a vestibulometry consultation), its opportunist character and the possible association with other more severe pathologies (meningiomas, multiple sclerosis, cerebellar venous angioma, vascular cerebral infarction) or more benign pathologies (labyrinth malformation, middle fossa atrophia). Sémont liberatory maneuver revealed to be much efficient (50% of patients free of disease after a single repositioning manoeuvre). Only 3 cases remaining unchanged after 2 years and intractable were proposed for surgery. We mention 7% of bilateral forms and 5% of alternating recurrent forms (sometimes on the right and sometimes on the left side). The recurrence is noted in 50% of BPPV followed at least during one year. We describe a particular topographic form concerning probably a cupulolithiasis of the external canal. 53% of cases beneficiated of CT-scan or of magnetic resonance imaging. The frequency and the possibility of pathological associations with BPPV bring to a particular vigilance for the diagnosis and to a particular care in the affirmation of the benignity in the case of long lasting vertigo (superior to 6 months), or when the nystagmus duration in Hallpike position is superior to 60 seconds.

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↗

PubMed1994

[Minor malformations of the ear ossicles. New classification and therapeutic results].

We tried to classify 46 minor malformations in 5 groups: 0: Normal ossicular chain, almost normal tympanic membrane but small atretic plate around malleus handle. I: Fixation of the malleus head. II: Normal ossicular chain but fixation of the footplate with or without abnormality of the facial nerve. III: Lack of a part of the ossicular chain with or without abnormality of the stapes. IV: Severe malformation of all the ossicular chain. We operated upon 4 malformations of type 0, 8 of type I, 10 of type II, 14 of type III and 10 of type IV. An air-bone gap within 20 dB was achieved in only 15 cases. As a matter of fact, in 9 cases the facial nerve covered the oval window; there were 4 pseudo-Mondini; ossiculoplasty was performed on a totally modified footplate in one case.

Abnormalities, Multiple↗

PubMed1993

Indirect immunofluorescence in the investigation of rapidly progressive sensorineural hearing loss and Menière's disease.

Being aware of the conservation of antigenicity, we performed indirect immunofluorescence on non fixed non decalcified frozen hamster's cochlea. Once killed, the heads of the hamsters were immediately dipped into liquid nitrogen and then stored at -20 degrees C until cutting. The sections were done at the same temperature, with Tissue-Tek embedding the heads to avoid breaking, using a sharp tungsten knife. The immunofluorescence itself was performed with the sera of the patients which were revealed through donkey fluorescein-conjugated antiserum to human immunoglobulins. For counterstaining, we used Evans blue. Twenty patients with rapidly progressive sensorineural hearing loss (according to the clinical criteria of MacCabe) and 6 with Menière's disease were tested. Five had a specific fluorescence on the stria vascularis. A correlation with the lymphocyte transformation test on human inner ear antigen has been found (p = 0.055).

Animals↗

PubMed1993

[Extensive cholesteatoma without intrapetrous involvement. Discussion on the surgical approach].

Based on 8 observations, the authors analyze the extension of middle ear cholesteatomas on the anterior attic and the anterior supralabyrinthine cellular groove, the internal retrotympanum and the posterior sublabyrinthine cellular groove, the hypotympanum and the anterior sublabyrinthine groove, the retrolabyrinthine region and the translabyrinthine and posterior supralabyrinthine grooves. Despite progress in imaging and optical instrumentation, exact precision of the lesions sometimes remains impossible. The patient must be warned of a possible enlargement of the operative pathway and its consequences.

Adult↗

PubMed1993

[Primary sclerosing cholangitis and autoimmune cochlear deafness: a new syndrome?].

Association of autoimmune cochlear hearing loss with primary sclerosing cholangitis is reported in two patients. Endocochlear sensorineural hearing loss was associated with the presence of anti-cochlear antibodies in the serum directed against the walls of vessels in the stria vascularis. The hearing loss appeared at the same time or shortly after the diagnosis of cholangitis. This association, which has never been described, may reinforce the theory of the role of immunologic factors in the pathogenesis of primary sclerosing cholangitis, possibly linked to or initiated by vasculitis.

Adult↗

PubMed1992

New immunobiological tests in the investigation of Menière's disease and sensorineural hearing loss.

The aim of the study was to determine the usefulness of new immunobiological tests using fractioned human inner ear antigen in the investigation of 4 Menière's disease and 12 rapidly progressive sensorineural hearing loss (RPSNHL). Each patient underwent a full ENT examination and a full range of immunobiological tests comprising ESR, electrophoresis, IgG, A, M, circulating immune complexes, cryoglobulins, complement, organ and non-organ auto-antibodies. The two new tests were the lymphocyte transformation test (LTT) and the immunoperoxidase test against total or fractioned human inner ear antigens. Four main bands were found in electrophoresis with the following molecular weights: 130,000, 45,000, 22,000, and 14,000. The heaviest band corresponded to IgG contained in the inner ear extract. Three cases of bilateral RPSNHL had positive LTT against inner ear antigens. No serum of patients showed a characteristics band with the immunoperoxidase test with regard to the serum of healthy subjects. At least four abnormal inflammatory non-specific tests were shown in the cases of positive LTT. Out of 3, 2 patients received steroids and improved their hearing.

Adult↗

PubMed1992

[Congenital cholesteatoma of the middle ear in children].

In a series of 16 middle ear cholesteatomas of a congenital type are reported in children; the youngest (18 months) presented with a bilateral case. Whereas a simple tympanoplasty could cure a localized pearl, typically anterosuperior in the mesotympanum, the stapes is fast eroded (7 cases) if progression goes on. Intact canal wall technique in 2 stages was the typical procedure. Good hearing results were generally achieved (except in one case of fixed footplate): 9 cases/14 with an ABG within 20 dB and an AC level within 30 dB.

Child↗

PubMed1992

Spontaneous retraction pockets in chronic otitis media medical and surgical therapy.

Results of a series of 228 spontaneous retraction pockets in chronic otitis media are reported and a classification is proposed. Under medical therapy, 78 retraction pockets of stage I and II (out of 95) were followed for five years. Sixteen percent deteriorated into stage III and were operated on; the others stabilized or improved towards normal tympanic membrane (23%). Different methods of surgical therapy were used in 150 retraction pockets (all the stages III and many stages II). Even with silastic sheeting and strengthening of the tympanic membrane, a recurrent retraction pocket was observed in 24 cases (16%). Functional results were obviously better when the ossicular chain was rebuilt from an intact malleus to an intact stapes and either from an intact malleus to a mobile footplate or from the tympanic membrane to an intact stapes. Surgery of retraction pockets must be used not only to prevent cholesteatoma formation but also to prevent erosion of the stapes.

Adult↗

PubMed1991

[Lipoma of the internal auditory canal. An anatomo-clinical case study and review of the literature about cranial nerve lipomas].

A 36-year-old female presented with vertigo and worsening of a right hearing loss with tinnitus. Clinical and radiologic investigations revealed a tumor of the right internal acoustic meatus, first diagnosed as a neuroma. Histologic study of surgical samples led to a final diagnosis of lipoma. Cranial nerve lipomas are rare and usually located in the cerebellopontine angle. Lipomas confined to the internal acoustic meatus are much rarer. The review of the literature however, shows that their histologic characteristics and their behavior are identical to those of cerebellopontine angle lipomas, and that a minimal surgical resection is therefore advised.

Adult↗

PubMed1991

Reconstruction of radical mastoidectomy by obliteration technique.

Reconstruction of radical mastoidectomy was performed by obliteration tympanoplasty using Palva flap in 199 ears either in one stage (normal mucosa, normal stapes, no risk of residual cholesteatoma behind the flap) or in two stages. At the 2nd stage, middle ear was reopened and the posterior cavity was checked in 34 cases. Bony pâté or ceramic granules may be added behind the flap, especially at this second stage. The closure of the tympanic membrane was achieved in 97% of cases. Residual cholesteatoma was removed in the middle ear at the 2nd stage in 17% of the ears. Late residual cholesteatoma behind the flap appeared in 5 cases where the posterior cavity had not been checked. Three early retraction pockets were due to technical failures which were more recently corrected by the use of fibromuscular graft placed between the fascia graft an the Palva flap. Three late retraction pockets progressed under the tympanic membrane from above to below. Hearing results were better in the 1st stage procedures, obviously selected: ABG within 20 dB in 83% of the ears with a normal stapes. On the contrary, in 2 stage procedures, ABG within 20 dB was achieved only in 50% of cases with a normal stapes and 29% of the ears where the crura were missing.

Adolescent↗

PubMed1991

[Value of immunobiological tests in Menière's disease and in rapidly progressive sensorineural deafness].

We have looked for abnormal immunobiologic test in 12 cases of Meniere's disease and 11 cases of rapidly progressive sensorineural hearing loss. After ruling out known etiologies, they were screened with non specific tests (sedimentation rate, electrophoresis, immunoglobulins, circulating immune complexes, cryoglobulins, complement system, auto antibodies) and inner ear specific tests (antibodies against human cochlea by indirect immunofluorescent test and lymphocyte transformation test against a pool of human inner ear. A non specific inflammatory syndrome was found in more than 50% of cases, specific tests of the inner ear were positive in 30% of cases. Corticosteroid therapy achieved a significant improvement of the hearing in 100% of the patients with a positive specific test, versus 50% of those with a negative result. A therapeutic protocol is suggested taking into account the results of the immunobiologic tests.

Deafness↗

PubMed1991

[Malformations of the bony labyrinth and deafness].

17 new cases of malformation of the bony labyrinth detected radiologically (tomography, CT) and associated with perceptive or composite deafness are reported. 2 cases discovered in spontaneous or traumatic recurrent meningitis are described, as well as 1 case discovered after the occurrence of total deafness following stapedial surgery. The malformations were unilateral in 7 cases, bilateral in 10. Deafness was of the composite type in 6 cases. An associated malformation of the middle or external ear was noted in 4 cases. 5 cases were included in a context of multiple malformations, including 1 case of otobranchiorenal syndrome, 1 case of Apert's syndrome and 3 cases of craniostenosis. Referring to the classification given by Mrs Vignaud and Jardin, we have encountered 1 case of stage I malformation, 9 cases of stage II, pseudo-Mondini malformation, 1 case of stage III or true Mondini malformation, 1 case of stage IV malformation, 3 cases of malformation of the aqueduct of the vestibule, ie. stage V. We have also encountered 2 isolate cases of stenosis of the internal auditory canal. On the basis of these cases, we report a few physiopathogenetic hypotheses and various classifications currently described in the literature. We also list the various associated external and middle ear malformations and the multiple-malformation syndromes that are commonly described. Stress is laid on the fact that these malformations often go undetected in congenital deafness, as well as on the usual course of these types of deafness for which there is no medical or surgical treatment.

Abnormalities, Multiple↗

PubMed1991

[Comparison between closed and open technique with muscular filling up in surgery of cholesteatoma of the middle ear. Long-term results].

Advantages and disadvantages of closed versus obliteration technique are studied in a serie of 348 ears all operated on by the senior surgeon, from January 1970 to January 1980. Closed techniques were performed in 67% of cases in children and 50% of cases in adults. A follow-up at one year was achieved in 98% of the cases, at 5 years in 50% and at 10 years in 25% of the cases. This study consists of long term results after all the scheduled surgery has been performed. Residual cholesteatomas occurred in 5% of closed techniques in 1 stage and 1% of closed techniques in 2 stages at one year, in 1.2% of closed techniques in 2 stages and 5% of obliteration techniques in 1 stage at 5 years. No other residual cholesteatomas were observed. Retraction pockets on the contrary were very frequent in closed techniques in 1 stage: 15% at 1 year, 11% at 5 years and 22% at 10 years. They were less frequent for closed techniques in 2 stages: 0.9% at 1 year, 6.3% at 5 years and 2.8% at 10 years. The same figure was observed for obliteration techniques in 1 or 2 stages: 1% at 1 year, 5 and 8.9% at 5 years and 5.8 and 5.2% at 10 years. The air-bone gaps were the same for closed techniques and obliteration techniques.

Adult↗

PubMed1990

[The open technique of tympanoplasty with obliteration using the Palva flap: technical details and indications].

Technical details of obliteration tympanoplasty with Palva flap are given with the 2 possibilities: 2 stages and 1 stage tympanoplasty. This technique is very convenient for adult cholesteatomas developed in a sclerotic mastoid with an extension limited to mesotympanum and attic, to the children cholesteatomas developed in the mesotympanum with a sclerotic mastoid, for the correction of retraction pockets after a closed technique, rehabilitation of radical mastoidectomies, fibroadhesive otitis and some idiopathic glue tympanic membrane with a large cholesterol granuloma.

Adult↗