Cochlear structures after implantation of a perimodiolar electrode array

OBJECTIVE

A perimodiolar prototype electrode array has been evaluated on 12 human temporal bone specimens. To achieve modiolar proximity, a fine Teflon positioner is attached to the tip and base of a conventional Nucleus 22 electrode array.

METHODS

Intracochlear electrode position was examined by macroscopic preparation and confirmed by a cochlear view x-ray after insertion into human temporal bones. The temporal bones were examined with light microscopy for intracochlear trauma after insertion, explantation, and re-implantation of the perimodiolar array.

RESULTS

Macroscopic preparation and x-ray confirmed close proximity of the intracochlear electrodes to the modiolar wall. In some bones, electrode insertion and positioning was performed without significant damage to intracochlear structures, but explantation caused varying degrees of trauma depending on the explantation technique used. Re-implantation and repeat explantation appeared to destroy most of the intracochlear architecture.

CONCLUSIONS

The perimodiolar electrode array prototype with Teflon positioner cannot be recommended for clinical use, especially in children in whom the possibility for re-implantation is high.

Interaction of folate and homocysteine pathway genotypes evaluated in susceptibility to neural tube defects (NTD) in a German population

Neural tube defects (NTD) are likely to result from an interaction of several genes and environmental factors. Because periconceptional folate intake reduces the NTD risk in the fetus, and because mothers of children with NTD showed elevated plasma homocysteine levels, gene polymorphisms of the folate and homocysteine pathway, such as 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C-->T, MTHFR 1298A-->C and cystathionine beta-synthase (CBS) 844ins68, have been implicated in the etiology of NTD. Several studies have demonstrated that these polymorphisms may indeed be associated with NTD in some populations. In order to evaluate the role of these polymorphisms and their interaction in NTD, we genotyped 417 individuals for case-control studies and 129 families for transmission disequilibrium tests. We are the first to present detailed data on MTHFR haploid genotypes in combination with CBS 844ins68. The MTHFR risk genotype 677CT/1298AC, known to be associated with decreased enzyme activity and increased homocysteine, was found significantly more often in patients than in controls (P = 0.02). A CBS insertion allele in addition to MTHFR 677CT/ 1298AC heterozygosity or MTHFR 677TT/1298AA homozygosity did not result in an increased risk for NTD. This is in agreement with the recently reported homocysteine-lowering effect of the CBS 844ins68 allele in carriers of MTHFR variants.

A screen for mutations in human homologues of mice exencephaly genes Tfap2alpha and Msx2 in patients with neural tube defects

BACKGROUND

Very little is known about the identity of genetic factors involved in the complex etiology of nonsyndromic neural tube defects (NTD). Potential susceptibility genes have emerged from the vast number of mutant mouse strains displaying NTD. Reasonable candidates are the human homologues of mice exencephaly genes Tfap2alpha and Msx2, which are expressed in the developing neural tube.

METHODS

A single-strand conformation analysis (SSCA) mutation screen of the coding sequences of TFAP2alpha and MSX2 was performed for 204 nonsyndromic NTD patients including cases of anencephaly (n = 10), encephalocele (n = 8), and spina bifida aperta, SBA (n = 183). A selected number of SBA patients was additionally tested for specific mutations in MTHFD, FRalpha, and PAX1 already shown to be related to NTD.

RESULTS

Two TFAP2alpha point mutations in individual SBA patients were silent on the amino acid level (C308C, T396T). On nucleic acid level, these mutations change evolutionary conserved codons and thus may influence mRNA processing and translation efficiency. One SBA patient displayed an exonic 9-bp deletion in MSX2 leading to a shortened and possibly less functional protein. None of these mutations was found in 222 controls. Seven polymorphisms detected in TFAP2alpha and MSX2 were equally distributed in patients and controls. Patients with combined heterozygosity of an exonic MSX2 and an intronic TFAP2alpha polymorphism were at a slightly increased risk of NTD (OR 1.71; 95% CI 0.57-5.39).

CONCLUSIONS

Although several new genetic variants were found in TFAP2 and MSX2, no statistically significant association was found between NTD cases and the new alleles or their combinations. Further studies are necessary to finally decide if these gene variants may have acted as susceptibility factors in our individual cases.

Gray-scale sonographic evaluation of cervical lymphadenopathy in cat-scratch disease

PURPOSE

The aim of this study was to characterize the gray-scale sonographic findings in the lymph nodes of patients with cat-scratch disease (CSD).

METHODS

We analyzed the sonograms of cervical lymph nodes in 41 patients with proven CSD between January 1997 and October 1999.

RESULTS

A total of 222 involved lymph nodes were detected. Involved nodes were most commonly found in the middle cervical (58%), parotid (37%), upper cervical (37%), and submandibular (17%) regions. We found acute, chronic, or abscessed lymphadenopathy in 63%, 12%, and 24% of patients, respectively. The size of involved lymph nodes ranged from 12 x 4 mm to 35 x 26 mm. The largest involved node had a short axis/long axis ratio of 0.5 or more in 61% of patients. Useful features for the differential diagnosis included markedly decreased echogenicity (100%), normal surrounding tissues (100%), and the presence of an echogenic hilum (76%). Posterior sound enhancement was significantly associated with larger and abscessed lymph nodes.

CONCLUSIONS

Despite the absence of a specific sonographic finding for CSD, gray-scale sonography can provide clues to the diagnosis of CSD in the proper clinical setting.

The Nucleus Contour electrode array: a radiological and histological study

OBJECTIVES

To evaluate the handling and insertion trauma of the recently developed Nucleus perimodiolar Contour electrode array (Cochlear Ltd., Pty, Lane Cove, New South Wales, Australia) in human temporal bones compared with the Nucleus standard straight electrode array.

STUDY DESIGN

E-perimental control group.

METHODS

Twenty-nine fresh-frozen bones were implanted with different electrode arrays by an experienced cochlear implant surgeon, and evaluated both radiologically and histologically.

RESULTS

Intracochlear insertion of the standard Nucleus straight electrode array was found to be atraumatic, confirming previous findings in the literature. Insertion of the Nucleus Contour electrode array resulted in instances of localized basilar membrane penetration causing the electrode array to move from the scala tympani into the scala vestibuli. However, this trauma did not result in any observable damage to the osseous spiral lamina or the modiolus. Basilar membrane penetration was observed in six of eight cochlear bones when a standard cochleostomy size (approximately 0.8 mm) and site (anterior and superior to the round window) were used. However, when the surgical technique was modified to use a slightly larger cochleostomy ( approximately 1.8 mm) situated closer to the round window and employ a partial stylet withdrawal technique during electrode insertion, the frequency of penetrations was restricted to two of seven bones. This trauma rate is comparable to that observed with other cochlear implants designs.

CONCLUSIONS

Following our results, the design of the Nucleus Contour electrode appears to fulfill the safety requirements for an intracochlear electrode array, provided that the surgical insertion technique is modified in the manner outlined.

Working conditions on stage: climatic considerations

Singers and actors frequently complain about dusty and dry theater environments, which they believe induce respiratory tract indispositions and decrements in vocal performance. In the literature to date, extremely few quantitative data exist about actual climatic conditions on stage. A previous study by our group in an unhumidified theater found that it had too high temperatures, too dry and too dusty air, based on German occupational guidelines for the generic workplace. In the present study, humidification units were installed in the same theater, and the environmental measures were repeated. The primary findings indicated that, following the activation of the humidification units, temperatures, humidities and fine dust concentrations were improved and generally within acceptable ranges for the generic workplace, although not always optimal. Where unacceptable performance environments exist, special care should be taken to counsel performers with regard to possible prophylactic measures such as individual steam inhalation and fluid intake.

Probiotics--compensation for lactase insufficiency

Yogurt and other conventional starter cultures and probiotic bacteria in fermented and unfermented milk products improve lactose digestion and eliminate symptoms of intolerance in lactose maldigesters. These beneficial effects are due to microbial beta-galactosidase in the (fermented) milk product, delayed gastrointestinal transit, positive effects on intestinal functions and colonic microflora, and reduced sensitivity to symptoms. Intact bacterial cell walls, which act as a mechanical protection of lactase during gastric transit, and the release of the enzyme into the small intestine are determinants of efficiency. There is a poor correlation between lactose maldigestion and intolerance; in some studies, low hydrogen exhalation without significant improvement of clinical symptoms was observed. Probiotic bacteria, which by definition target the colon, normally promote lactose digestion in the small intestine less efficiently than do yogurt cultures. They may, however, alleviate clinical symptoms brought about by undigested lactose or other reasons.

[Evaluation of a structured education program for adult outpatient asthmatics]

BACKGROUND AND METHODS

The efficacy of a structured education programme (AFAS) unter outpatient conditions was evaluated in a pilot study including 25 mild to severely ill adult asthmatics (age 41 +/- 2 yrs.) over a period of two and a half years. The main teaching items of the programme are: self-control of the disease with regular peak flow measurements, monitoring of symptoms with a patient diary, effects and side effects of the treatment, correct inhalation technique of asthma medication and the ability of self-management with regard to the actual degree of airflow limitation by the patients.

RESULTS

After AFAS the knowledge of the patients regarding the disease as well as the medication increased significantly. There was an improvement of drug therapy: before AFAS only 52% of the patients used inhaled steroids on a regular basis with regard to 96% one and two years after participation of AFAS (p < 0.01). The self-control of the disease was improved: before AFAS no patient measured peak flow during acute dyspnoea, compared with 88% (p < 0.001) and 75% (p < 0.001) one and two years after AFAS, respectively. The number of severe asthma-attacks decreased significantly from 10.7 +/- 2.5 per patient and year before education to 1.3 +/- 0.2 (p < 0.001) after the first year and to 2.0 +/- 0.3 (p < 0.05) after the second year. The total number of hospital days due to asthma decreased from 219 days in the year before the participation in AFAS to zero (p < 0.001) in the first year after the education and to 17 days (p < 0.001) after the second year.

CONCLUSIONS

The efficacy of patient education with AFAS is still evident two years after the course, but a reduction of self-control of the disease was observed during the follow-up period. In conclusion, structured education programmes for adult asthmatics can be effective even under outpatient conditions.

Epiglottic tuberculosis: differential diagnosis and treatment. Case report and review of the literature

A case of a 40-year-old man with tuberculous involvement of the epiglottis suffering from unsuspected pulmonary tuberculosis is described. The laryngeal lesions were primarily considered to be highly suspicious for a neoplastic process rather than an infectious one. After diagnosis, the patient was treated according a standard protocol and followed up for a period of 2 years. He is still free of disease. The clinical presentation, diagnosis, pathological findings, and therapy of the condition are described. The differential diagnosis and management of epiglottic tuberculosis are reviewed and discussed. Even though these cases are rare, otorhinolaryngologists should keep in mind the possibility of tuberculosis in the differential diagnosis of laryngeal tumors, as the incidence of tuberculosis in developed countries is steadily increasing.

The need for psychosocial support in parents with cochlear implanted children

OBJECTIVE

The aim of the study was to assess the need of parents with Cochlear implanted children for psychosocial support, based on psychic symptoms reported by these parents and their motivation to make use of psychosocial interventions.

METHODS

Fifty seven mothers and 46 fathers of 57 Cochlear implanted children were evaluated separately, employing validated questionnaires (Symptom Checklist-90-R and Questionnaire on Psychosocial Support).

RESULTS

26% of the mothers and 25% of the fathers showed severe psychic symptoms as reflected in the Symptom Checklist-90-R. Fifty nine percent of the mothers and 60% of the fathers were highly motivated to participate in psychosocial interventions--especially in the form of further information on their children's ailment and in parents' groups.

CONCLUSIONS

The data presented suggest that there is a need for psychosocial support in 18% of the parents; 8% of the parents show high psychic stress, but low motivation. The rest of the parents are not in need of support; nevertheless, 42% of the parents are highly motivated in favor of psychosocial interventions.

[Psychological stress, knowledge and treatment expectation of parents with a child managed by cochlear implant]

ESTABLISHED KNOWLEDGE: It is known that parents of hard-of-hearing children suffer from an increase in psychosocial stress.

SCIENTIFIC QUESTION

How does the psychosocial situation of parents with children who have cochlear implants change during rehabilitation?

AIM OF STUDY

It was the aim of this study to demonstrate how parents evaluate retrospectively their own psychological well-being during the process of rehabilitation.

METHODS AND RESULTS

We interviewed 87 parents by questionnaires which were mailed to them. Fifty-seven mothers and 46 fathers responded (59% return rate). Parents reported a significant increase in stress, as perceived by themselves, after the time of diagnosis. Of the parents, 25% continued to suffer from psychic stress during rehabilitation as could be demonstrated by the SCL-90-R questionnaire criteria. The expectations by parents were realistic prior to implantation but thereafter increased significantly with time.

CONCLUSIONS

The psychological state of parents during the critical phase, after a diagnosis of deafness has been made for their child, has to be considered. Even after an initial phase of shock, parents seemed to be stressed to an extent that required therapeutic intervention.

Chemiluminometric determination of tissue polypeptide antigen (TPA), cancer antigen 15-3 (CA 15-3), carcinoembryonic antigen (CEA) in comparison with vascular endothelial growth factor (VEGF) in follow-up of breast cancer

Vascular endothelial growth factor (VEGF), tissue polypeptide antigen (TPA), cancer antigen 15-3 (CA 15-3) and carcinoembryonic antigen (CEA) were measured in 314 sera of breast cancer patients and in 58 sera of women without breast cancer. VEGF was determined using a sandwich enzyme immunoassay technique (ELISA) and the tumour markers TPA, CA 15-3 and CEA with an immunoluminometric assay (ILMA). The breast cancer patients were staged according to the TNM classification stages 0-IV (by UICC) in patient groups with a compatible prognosis. Median and range of each stage were investigated. The cut-off values (95th and 97.5th percentile of control group) of VEGF, TPA, CA15-3 and CEA were determined; sensitivities for each parameter and for all combinations of two parameters were investigated for these cut-offs and the receiver operating characteristic (ROC) curves were calculated. The differences between the control group and stages 0-3 were shown to be non-significant for CA 15-3 and CEA but significant for VEGF and TPA. Significant differences were found in stage 4 for VEGF and all three markers. The increase in sensitivity of VEGF from stage 0 to stage 3 and the decrease from stage 3 to stage 4 can be interpreted based on the role of VEGF in the angiogenesis. The quantification of VEGF could give additional information for selecting patients for systemic adjuvant therapy.

[Parotid involvement in cat scratch disease: a differential diagnosis with increased significance]

BACKGROUND

Bartonella henselae is the causative agent of cat-scratch disease (CSD), an inflammatory infection of the lymph nodes. So far, only few cases of atypical manifestations in the head and neck, especially manifestations in the parotid gland have been reported.

PATIENTS AND METHODS

Between January 1997 and June 1999 seven patients with manifestations of CSD in the parotid gland were observed at the ENT-department Freiburg. The positive diagnosis was confirmed serologically by an indirect immunofluorescence assay and by detection of Bartonella henselae-DNA with PCR-amplification and subsequent hybridization or sequencing.

RESULTS

An intraglandular abscessed lymphadenitis was found in five patients, two of these cases were based on a Parinaud's oculoglandular syndrome. A diffuse affection of the parotid gland, initially misinterpreted as a parotid tumor, was seen in two patients.

CONCLUSIONS

Antibiotic treatment is recommended in order to reduce the duration of the disease, in cases of pain and lymph node abscesses. In uncommon manifestations of CSD, the nosological assignment can be difficult on the basis of the heterogeneous symptomatic in the individual patient and the CSD diagnosis can only be confirmed by serology or PCR-based techniques. CSD should be considered in the differential diagnosis of all equivocal masses in the head and neck, even in unusual localisations like the parotid gland.

Effects of on-demand beta2-agonist inhalation in moderate-to-severe asthma. A randomized controlled trial

BACKGROUND

The appropriate use of short-acting beta2-agonist inhalation in asthma has been the subject of controversy in recent years. Limited information is available for the group of moderate to severe asthmatics with high intake of bronchodilator inhalants and continuous anti-inflammatory protection.

OBJECTIVE

To investigate the effects of beta2-agonist reduction in marked asthma treated with multiple asthma medications.

DESIGN

Randomized, controlled single-blind, cross-over trial.

SETTING

Outpatient clinic at a university medical centre.

SUBJECTS

A total of 80 adult patients with moderate-to-severe asthma.

INTERVENTIONS

In a 1-year study patients were assigned to on-demand vs. regular beta2-agonist inhalation treatment.

MAIN OUTCOME MEASURES

Asthmatic episodes (primary outcome), symptoms, peak expiratory flow rates (PEF) and drug use were recorded daily. Bronchodilator and airway responsiveness, lung function indices and quality of life were assessed during five clinic visits. Also, practicability of beta2-agonist tapering in multimedicated asthmatics was analysed.

RESULTS

More than 80% of moderate-to-severe asthmatics were able to reduce their beta2-agonist intake by >/=50%. Puffs per day of active therapy decreased from 7.9 in regular to 3.3 in on-demand treated patients (P = 0.0001). The type of beta2-agonist used (salbutamol/fenoterol) had no significant impact on the study findings. Almost all parameters of control of asthma improved during the on-demand treatment period.

CONCLUSION

On-demand inhalation of short-acting beta2-agonists in moderate-to-severe asthma is safe, and even in severe asthma a reduction from regular to on-demand beta2-agonist inhalation is possible, with improved asthma control.

Esophageal atresia in Bremen, Germany--evaluation of preoperative risk classification in esophageal atresia

BACKGROUND/PURPOSE

The current study enrolled 113 patients with esophageal atresia (EA) accompanying tracheoesophageal fistula (TEF) (Vogt type IIIb) who were treated at the Central Hospital St. Jürgen Strasse, Department of Pediatric Surgery in Bremen, Germany between 1978 and 1997.

METHODS

These EA patients were classified into patients preoperatively complicated by respiratory distress syndrome (RDS) or pneumonia and those without complications. In each group, risk factors were classified according to the risk classification described by Spitz et al, and the prognoses and therapeutic problems were evaluated. Based on these results, a new preoperative risk classification consisting of risk factors described by Spitz et al supplemented with RDS and pneumonia was evaluated.

RESULTS

When the prognoses of EA were evaluated, the survival rate was markedly decreased when RDS or pneumonia alone or more than 2 of 3 factors including major cardiac anomalies and low birth weight were present as preoperative risk factors. Concerning therapeutic problems, the necessity of treatment with delayed primary repair tended to increase when RDS or pneumonia was present as risk factors. However, it was suggested that secure and safe blockage of TEF was still difficult during the initial surgery.

CONCLUSIONS

During selection of therapeutic strategies for EA, RDS and pneumonia are still considered to be essential as preoperative risk factors for EA. Our new preoperative risk classification consisting of risk factors described by Spitz et al supplemented with RDS and pneumonia appears to clearly reflect the prognoses and therapeutic problems of EA.

Atomic structure of the polar NiO(111)- p(2x2) surface

Using grazing-incidence x-ray diffraction, the p(2x2) surface structures of the single crystal NiO(111) and a 5 monolayer thick NiO(111) film on Au(111) were both shown to exhibit locally the theoretically predicted octopolar reconstruction, with some important differences. The single crystal exhibits a single Ni termination with double steps. The thin film exhibits both possible terminations (O and Ni) and single steps. These surfaces were found to be nonreactive with respect to hydroxylation.