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C von Ilberg

Publications and source records attributed to C von Ilberg.

At least 19 recordsLinked to original sources
PubMed2000

Optimized speech understanding with the continuous interleaved sampling speech coding strategy in patients with cochlear implants: effect of variations in stimulation rate and number of channels.

The purpose of this study was to investigate the effect of systematic variations in stimulation rate and number of channels on speech understanding in 13 patients with cochlear implants who used the continuous interleaved sampling speech coding strategy. Reducing the stimulation rate from 1,515 to 1,730 pulses per second per channel to 600 pulses per second per channel resulted in decreased overall performance; the understanding of monosyllables and consonants was more affected than the understanding of vowels. Reducing the number of active channels below 7 or 8 channels decreased speech understanding; the identification of vowels and monosyllables was most affected. We conclude that vowel recognition with the continuous interleaved sampling strategy relies on spectral cues more than on temporal cues, increasing with the number of active channels, whereas consonant recognition is more dependent on temporal cues and stimulation rate.

Cochlear Implantation↗
PubMed1999

Prognostic significance of polo-like kinase (PLK) expression in squamous cell carcinomas of the head and neck.

Previously, we demonstrated that the mammalian polo-like kinase (PLK), which participates in the regulation of the cell cycle, is a novel marker of cellular proliferation. Because current prognostic tools for the evaluation of patients with head and neck squamous cell cancer (HNSCC) need to be improved, we analyzed 89 patients and found elevated PLK expression in most tumors. Nodal stage as a crucial prognostic factor in HNSCC also correlated to PLK transcript levels (P = 0.0043). A Kaplan-Meier analysis showed that HNSCC patients with moderate versus high PLK expression survived significantly longer (5-year survival rates, 43% versus 12%; P = 0.0047). Interestingly, a combination of nodal stage and PLK expression contributed to discriminate patients with a better prognosis in the pN(0/1) and pN(2/3) groups, which could improve the definition of a suitable therapy.

Adult↗
PubMed1999

[Immunoglobulin subclass defects in patients with therapy refractor chronic rhinosinusitis].

In the present study 220 patients suffering from recurrent rhinosinusitis and not responding to antibiotic treatment were evaluated for a defect in IgG-immunoglobulin subclasses. Twenty-one of these patients were found to have an antibody deficiency. These included deficiencies of IgG-2 (n = 10), IgG-1 (n = 6), IgG-3 (n = 1) and IgG-4 (n = 1). A common variable immune disease was diagnosed in three patients that was characterized by an additional defect in the IgG main class. However, an IgG subclass deficiency can only be ascertained by an immunological evaluation. The significance of a deficiency can be identified by a reaction to vaccination using (for example) protein or polysaccharide antigens. Treatment consists of antibiotics, intravenous immunoglobulins and long-term follow-up. Endonasal microsurgery should only be performed in cases that do not respond to conservative treatment. It is particularly necessary to observe these patients because a deficiency of immunoglobulin subclass in certain cases is the first sign of an immunological impairment that can advance to a severe immunodeficiency and predispose to the development of malignancy.

Adolescent↗
PubMed1999

Immunoglobulin deficiency and determination of pneumococcal antibody titers in patients with therapy-refractory recurrent rhinosinusitis.

We examined 245 patients with chronic rhinosinusitis not responding to prolonged antibiotic treatment and tested each patient for humoral antibody deficiencies. Low immunoglobulin levels were found in 22 patients. Five of them had defects of two or more immunoglobulin isotypes that were diagnosed as common variable immunodeficiency (CVI). Seventeen had an IgG-subclass deficiency. Before and after immunization with pneumococcal vaccine, serotype-specific pneumococcal antibody levels were determined to further evaluate the relevance of the underlying deficiency. Significantly reduced antibody titers of pneumococcal serotypes were found in CVI patients (n = 5), while immunization of 17 patients with IgG-subclass deficiency gave different results. Three of the 17 patients responded poorly to pneumococcal immunization and were prone to a polysaccharide specific immunodeficiency. Patients with CVI or IgG-subclass deficiency failing to produce protective antibody levels in more than five serotypes were chosen for antibiotic and/or immunoglobulin substitution therapy. Since recurrent sinusitis in these patients did not resolve with adequate conservative therapy, endonasal microsurgery was then performed and was seen to be a valuable therapeutic option. Our study suggests that an IgG-subclass deficiency may be the first sign of a basic immunological change, resulting in persisting sinus infections.

Adolescent↗
PubMed1997

Bone replacement by ionomer cement in osteoplastic frontal sinus operations.

Ionomer-based cement is a new bone replacement material. After promising results in middle ear and skull base surgery, we started to use Ionocap as an alternative to metal osteosynthesis material. Between 1992 and 1995, 20 men and 9 women were treated with an osteoplastic approach for complicated frontal sinus diseases at Johann Wolfgang Goethe University. Ionocap as bonding material for bone was used in 22 of the patients. The indications for osteoplastic surgery were recurrent frontal rhinosinusitis, mucoceles, skull base fractures, osteomas and meningocele. The surgical procedure using bone cement was found to be much easier and shorter, the functional stability achieved was at least equal and the cosmetic outcome was clearly superior when compared to cases done with metal osteosynthesis. No rejection of the material or osteonecrosis was observed. In no case was the cement placed in direct contact to dura mater. Our findings show that ionomer-based cement can be recommened in osteoplastic frontal sinus surgery, but Ionocap should only be used strictly according to the guidelines of the supplier.

Adolescent↗
PubMed1997

[Chloride conduction of nasal fibroblasts in polyposis patients with cystic fibrosis and in patients without cystic fibrosis. Relevance for the ENT physician].

Cystic fibrosis (CF) is a complex systemic disease that has pathological alterations in the upper airways, including the recurrent formation of nasal polyps. Although the fibroblast is the predominant cell type in nasal stroma and nasal polyps, little is known about the electrophysiological properties of nasal fibroblasts. We investigated whether fibroblasts possess a cAMP-regulated chloride conductance which is impaired in patients with CF. Thus far the few studies concerning conductance in fibroblasts have been performed on skin fibroblasts using indirect methods and have yielded conflicting results. Therefore we studied chloride conductance in fused nasal fibroblasts by employing conventional microelectrodes. We have demonstrated that a cAMP-regulated chloride conductance is present in fibroblasts. However, this chloride conductance cannot be activated in fibroblasts from CF-patients. Thus, we present direct evidence that the impairment of the cAMP-regulated chloride conductance in CF is not confined to epithelial cells but also affects the fibroblast. We discuss how this conductance might modulate fibroblast proliferation to produce polyp formation.

Child↗
PubMed1997

Optimization of channel number and stimulation rate for the fast continuous interleaved sampling strategy in the COMBI 40+.

OBJECTIVE: To investigate the interrelation between number of channels and stimulation rate in the continuous interleaved sampling strategy (CIS). SUBJECTS AND METHODS: Three of the first recipients of the new COMBI 40+ cochlear implant participated in consonant, vowel, number, and sentence tests. Speech understanding was evaluated for different combinations of number of active channels from two to twelve and stimulation rate per channel between 1,515 and 9,090 pulses per second. RESULTS: The results indicate that the optimum number of active channels is not necessarily the maximum number of usable channels.

Adult↗
PubMed1996

A follow-up study of long-term results after cochlear implantation in children and adolescents.

The time course of speech development in children after cochlear implantation may extend over many years, thus making long-term studies necessary to evaluate any outcome. We report our long-term results after cochlear implantation in children and adolescents. Mean follow-up was 28 months, ranging from 1 to 5 years. After at least 1 year of experience all children were found to benefit from their cochlear implants. The majority of children scored above chance in speech identification tasks requiring closed set word and sentence understanding). At the 4-year interval, all children tested including prelingually deaf children had developed open set sentence understanding. The most relevant factor accounting for differences in the results was the duration of implant use in all groups. Even beyond 3 years the results continued to improve. Peri- or postlingually deafened children tended to have favorable results. For prelingually deaf children, duration of deafness and age at implantation were correlated negatively with the results.

Adolescent↗
PubMed1994

[Immunoscintigraphy of carcinomas in the area of the head-neck with technetium-99m marked monoclonal antibody 174H.64. A new diagnostic procedure].

Twenty-one patients with squamous cell carcinomas of the head and neck were studied by immunoscintigraphy and immunoemission, computed tomography (ECT) using monoclonal antibody 174H.64 (Biomira Edminton) labelled with 99Tcm (Schwartz Method). Immunoscintigraphic results were compared with routine clinical assessments, including CT and ultrasonography, and were controlled by histopathological examination after surgery. All primary localizations (pT1 = 3, pT2 = 3, pT3 = 7, pT4 = 5; oropharynx 7, larynx 5, hypopharynx 3, oral cavity 3, lymph nodes 3) could be visualized, while 15 out of 18 neck lesions from tumor metastases could also be visualized (pN1 = 8, pN2 = 8, pN3 = 2). In one case with micrometastases in lymph nodes that could not be demonstrated by other methods, staging was upgraded by the immunoscintigraphic results. Three other micrometastases in lymph nodes could not be visualized. Distant metastases were suspected in 5 cases, three of which were confirmed either histologically or by radiography. Two of the cases with distant metastases were detected by the immunoscintigraphy. The present results indicate that immunoscintigraphy in combination with immuno-ECT can improve preoperative staging of head and neck carcinomas, especially with regard to metastatic neck disease, tumor recurrences and some cases of distant metastases.

Antibodies, Monoclonal↗
PubMed1994

[Microsurgery of the nose and paranasal sinuses; concept, technique and result].

1. The close relationship between an impaired nasal air passage or chronic diseases of the paranasal sinuses and the bronchial system seems to be generally accepted. 2. Any improvement of the nasal respiration and chronic infections of the sinuses obviously have a positive effect on pathologic lung function, bronchitis and asthma. Even though a causal connection between the treatment of the chronic nasal and paranasal infection and the decrease of pulmonary symptoms in chronic bronchitis and asthma could not be verified yet by valuable statistics, the transnasal surgery reduces heavy nasal symptoms in more that 90% of our cases. 3. We consider endonasal microsurgery to be the safest and most convenient technique in the treatment of chronic nasal and paranasal diseases. This minimal invasive surgery therefore is suitable as well for the treatment of recurrent diseases which unfortunately cannot be avoided in this area.

Desoxycorticosterone↗
PubMed1991

[Computerized tomography as routine examination procedure in the diagnosis of paranasal sinus diseases from the otorhinolaryngologist's viewpoint. Results].

The renaissance of endonasal microsurgery is not only based on a deeper knowledge of the mucociliar clearance and better operation instruments but depends as well as on the improved radiological diagnosis provided by computed tomography. Since 1986, high-resolution computed tomography in two plains has been part of the authors' preoperative routine diagnostic program for paranasal sinus diseases at their clinic. One hundred and fifty-eight computed tomograms of patients with chronic rhinosinusitis, complicated acute rhinosinusitis, and polyposis nasi were reexamined. The involvement of the paranasal sinuses and abnormalities of the lateral nasal wall were analyzed. The anterior ethmoid is the most frequently affected area in all of the diseases. The computed tomogram is most important for the rhinosurgeon. The ethmoid cell system can be visualized without superimposing structures. Therefore even circumscript pathologic mucosa alterations and the extent of the disease can be defined. All this enables the surgeon to put forward an exact diagnosis and to plan a safe operation as regards important physiological structures of the nose and paranasal sinuses.

Adolescent↗
PubMed1991

[Possibilities of treating nasal turbinates in the framework of endonasal microsurgery].

Pathologic alterations of the turbinates are common in infectious diseases of the nose and paranasal sinuses. Over 300 patients were treated for paranasal sinuses disease from 1986 to 1989 by endonasal microsurgery. One-third of the patients were found intraoperatively to have alterations of the middle and inferior turbinate causing obstruction and functional disorders of the nose and sinuses. Our concept comprises a step-by-step microsurgical approach to the turbinates. The technique and the results are presented.

Airway Obstruction↗
PubMed1990

[Tumor-associated macrophages (TAM) in the stroma of squamous cell carcinomas of the ENT area studied using monoclonal antibodies].

Monoclonal antibodies were used to examine the presence and nature of tumor associated macrophages and T-lymphocytes in 26 cases of squamous cell carcinoma of head and neck. The content of macrophages varied according to the differentiation of the carcinoma: high differentiation was evidenced by a labelling index by an index between 13.5% and 23.7%, poor differentiation from 27.4% to 35.8%. T-lymphocytes were found where tumors were inflamed, but there was no significant correlation between tumor differentiation and infiltrating T-lymphocytes. The present results that prognosis decreases with the increasing number of tumor associated macrophages in squamous cell carcinoma.

Antibodies, Monoclonal↗