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W Maier

Publications and source records attributed to W Maier.

At least 37 records · Page 2Linked to original sources
PubMed2006

[The transverse rectus abdominis muscle (TRAM) flap. A "second defensive line" in microvascular reconstructions of defects in the head and neck area].

BACKGROUND: The microvascular anastomosed transverse rectus abdominis muscle (TRAM) island flap has been successfully used in plastic surgery for more than 10 years. In reconstructive head and neck surgery, however, it is not yet established. METHOD: We analysed the preparation and anatomical variation in TRAM flaps in an examination of eight cadavers. In a clinical case with complete reconstruction of the nose after nasal ablation and complete loss of a radial lower forearm flap that had been transplanted previously due to a recurrent tumor, the possibility of forming and modeling a TRAM flap is demonstrated. RESULTS: The flap vessels of the TRAM are comparable to the radial forearm flap, and the donor site may be primarily closed. The TRAM proved to be a suitable alternative to close lesions of the head and neck area in selected cases. The myocutaneous TRAM is bulkier than the fascio-cutaneous radial forearm flap. The subcutaneous abdominal fat of the TRAM can be reduced in relation to the vascular distribution of the perforator vessels. If the subcutaneous fat of the flap is reduced, the flap can be shaped and formed well. In the described case, it was used to close the lesion after ablation of the nose and middle face. CONCLUSION: The risk of an iatrogenic lesion of the peritoneal fascia or postsurgical herniation of the abdominal wall is low if several surgical prerequisites are taken into consideration. The myocutaneous TRAM will not replace the fascio-cutaneous radial forearm flap in microvascular head and neck surgery, but the large diameter of the donor vessels and the highly vascularized flap tissue makes it an alternative as a second line procedure in cases of unfavorable wound conditions.

Cadaver↗
PubMed2006

[Skull base chondrosarcoma. An interdisciplinary challenge].

BACKGROUND: Chondrosarcoma is a rare differential diagnosis of malignant tumours of the skull base. The prognosis was rated as unfavourable in articles for many years. It has, however, improved considerably in recent years. The objective of this study was to evaluate and current, new optimised treatment strategies. PATIENTS AND METHODS: We retrospectively analysed the case histories and course of four patients whom we treated for chondrosarcoma of the skull base over the past 5 years at the Freiburg Skull Base Centre. RESULTS: Because of initially mild symptoms, the patients first came for examination at an advanced stage of the tumour. All patients underwent surgery, whereby an R0-resection was barely or only questionably present. Three patients underwent radiation therapy postoperatively. All patients are currently tumour free. CONCLUSIONS: Surgical treatment with curative intent is basically the therapy of choice. Due to the usually large size of the tumour and its close relationship to relevant structures, complete resection is, however, not always possible despite advances in surgical procedures. Taking the possibility of modern adjuvant radiotherapeutic procedures into account, an incomplete, function-preserving resection is preferred to a radical and mutilating resection.

Adult↗
PubMed2006

[Objectivity of therapeutic results following skull base surgery using virtual model analysis].

BACKGROUND: Virtual model analysis of patient head tracking allows for objectivity and the monitoring of therapeutic results of pathologies in the skull base region. The introduction of these models in clinical routine has been impaired by the extended time needed for the preparation of radiological data. METHODS: Quality control analysis was carried out for seven cases with different pathological findings in the skull base region in patients who had undergone virtual model analysis. RESULTS: Preparation time of radiological data for the process of segmentation required, under optimal conditions, a minimum of 30 min. Virtual model analysis enables spatial visualization of regions of interest and adjacent anatomical structures. This improves case-specific pathoanatomical understanding as well as preoperative planning of surgical strategies. CONCLUSIONS: Virtual model analysis improves the physician's spatial comprehension of localized pathological findings at the dysmorphic interface of bone and soft tissue across the skull base. Therefore, it seems to be an adequate tool for quality control analysis of therapeutic results after extended skull base surgery.

Adolescent↗
PubMed2006

[Single and temporally displaced second nerve lesions in an animal model and their clinical significance].

BACKGROUND: Surgical optic decompression after trauma has been discussed controversially. The surgical trauma is supposed to produce an additional nerve lesion with the danger of complete loss of vision. Alternatively, conservative high dose cortisone therapy has been recommended. METHODS: The functional and morphological consequences of a lesion after calibrated optic compression in one or two sessions were examined in an animal model using 29 Wistar rats. RESULTS: Depending on the duration and intensity of the lesion, we observed a linear decline in the number of neurons in the RGC (retinal ganglion cell) layer as well as an increasing reactivity to GFAP (glial fibrillary acidic protein) as an indication of central gliosis of astrocytes; however, this was independent on whether optic compression was performed in one or two sessions. CONCLUSIONS: To reduce secondary damage to the visual nerve and the central visual system that might increase with a persisting lesion, the indication for surgical relief of an eye affected by afference should be considered liberally, especially in view of the low morbidity of rhinosurgical intervention.

Animals↗
PubMed2006

[Advances in neurobiological understanding of schizophrenia. Perspectives for new therapeutic concepts].

Causal treatment options for schizophrenia are lacking due to our restricted knowledge of its etiology and pathogenesis. However, recently three postulated disposition genes for schizophrenia have been increasingly better confirmed: dysbindin, neuregulin-1, and G(72)/DAOA genes. These genes code proteins involved in processes ranging from brain development to the maintenance of glutamatergic transmission in the mature brain. Current interpretation of neuroanatomical findings points at reminiscences of disturbed brain development and a loss of nonneuronal elements, the so-called neuropil, as a correlate of brain atrophy. This reduction in neuropil is mainly caused by synaptic elements. Biochemical findings supporting this show that besides the dopaminergic and serotonergic system, glutamatergic transmission is also disturbed in schizophrenia. All these findings fit very well with the presumed functions of the disposition genes. Hypothesis-free approaches in structural brain imaging and the combination of functional imaging with relevant gene variants open new avenues for using markers from brain imaging to improve the diagnosis of schizophrenia and judge the response to neuroleptic treatment. Despite the enormous increase in knowledge for example in genetic research, the risk variants known until now provide no contribution to early diagnosis of schizophrenia. Furthermore, pharmacogenetics is currently unable to give a clear answer as to whether a single patient is responding to treatment or not.

Animals↗
PubMed2006

[Attitudes towards predictive genetic testing for Alzheimer's disease].

Most neuropsychiatric disorders have a complex aetiology. Discovery of the underlying genetics will provide insights into the disorders and allow the subsequent development of therapeutic interventions based upon an understanding of causality. The first vulnerability genes in Alzheimer's disease (AD) have been identified. The contribution of each vulnerability gene to the disorder is limited and does not enable prediction of course and onset in individual cases, only modification of the a priori risk. However, people may wish to be informed about this modification. Professionals have not favoured this form of predictive testing due to an awareness of its limitations and its potential for harm. However, little is known about public attitudes and understanding of such genetic testing in neuropsychiatric disorders. The aim of our study was to assess the attitudes of the general population and to explore the influence on these attitudes of knowledge about the illness and the understanding of risk information. In our study, a representative sample of the German general population (n=2001), relatives of patients with Alzheimer's disease (n=101) and physicians (n=43) were interviewed about their attitudes towards genetic tests for Alzheimer's disease and their perception and interpretation of risk information. To assess the influence of genetic counselling on these factors, 234 people were questioned before, and four weeks after, they were provided with detailed relevant information. Our results indicate that a substantial proportion of the German population (57%) is in favour of psychiatric genetic testing for AD in general. Even when the explanatory power of a genetic test is limited, a substantial proportion of the population (47%) expressed an interest in genetic testing. Counselling slightly decreased the interest in having a genetic test for oneself (from 47% to 38%). Physicians were more hesitant than both relatives and the general population concerning predictive genetic testing. Only a minority (11%) favoured prenatal genetic testing. Our results also show that both knowledge about AD and the capacity to interpret risk estimates are limited. While physicians' estimation of their personal risk for developing AD approximated to the actual average risk for the population, people in the general population and the relatives of AD patients tended to overestimate their personal risk. However, most of the general population still perceived this risk as average or low. While most physicians could correctly interpret information regarding the probability of risk, only one third of AD patients' relatives or members of the general population could. As the decision of an individual to undergo predictive testing relies mainly on his understanding of risk, the ability to correctly interpret risk information will be of crucial importance in the future. From a medical perspective, the prevailing approach of professional associations to genetic testing appears reasonable and therefore should not be changed at present.

Adult↗
PubMed2006

[Pseudodominants of two recessive connexin mutations in non-syndromic sensorineural hearing loss?].

BACKGROUND: Hitherto more than hundred genes and gene loci for non-syndromic or syndromic deafness have been identified. Mutations in the connexin 26 gene (GJB2) account for up to 50 % of the cases of autosomal recessive hearing loss. The genes GJB2 (Connexin 26), GJB3 (connexin 31) and GJB6 (connexin 31) are located on chromosome 13q11-12. In the inner ear up to four different connexins are expressed. Connexins appertain to a group of gap junction proteins. These proteins can oligomerize to form single-membrane channels called connexons. Each connexon is composed of six subunits, that allow communication between adjacent cells by providing a channel for diffusion of ions, metabolites and second messengers. METHOD: Each of the exons and flanking splice regions of the connexin 26, 30, and 31 genes (GJB2, GJB3, and GJB6) have been analysed by direct sequencing. RESULTS: In the involved families three heterozygous mutations could be detected in the connexin 26 (GJB2) and connexin 30 (GJB6) genes. If a combination of two of those mutations occurs, 35DeltaG with 146/147DeltaC and 35DeltaG with GJB6-D13S1830 it results in hearing loss and deafness. CONCLUSION: By evidences of a familial background of hearing loss it is reasonable to analyse the connexin genes (GJB2, GJB3 and GJB6) for mutations, additionally to a specific hearing diagnostic, in order to enhance linguistic development through hearing aid or CI-implantation at an early stage.

Adult↗
PubMed2006

[Ethisorb/Ethisorb durapatch for the transnasal duraplasty procedure?].

BACKGROUND: Defects of the dura in the rhinobasal area can be closed transnasally. Various procedures with autologous or alloplastic material can be chosen. METHOD: From 2001 to 2004, we closed a rhinobasal dura defect with Ethisorb or Ethisorb durapatch in sandwich technique in 8 patients. After smoothing the bone edges, Ethisorb is applied under microscopic or endoscopic view endocranially, extradurally as "underlay" to seal and absorb the liquor pressure pillar. Additionally, another Ethisorb implant as "underlay" is applied extracranially from endonasally as "underlay", and sealed with a further layer of nasal concha mucosa with fibrin glue. RESULTS: All patients were successfully treated with this technique. There were no evidences for persisting rhinoliquorrhoe after the period of wound healing. For hemostasia, a nasal package was applied for compression at the donor site of the inferior nasal concha. The former dura defect was at all times freely accessible in order to be able to recognize a possible new rhinoliquorrhoea early and to prevent a possible congestive secretion with superinfection. DISCUSSION: The material of Ethisorb and Ethisorb durapatch is stiff and can be easily modelled, so it is an alternative as an alloplastic material for endonasal closure of defined substantial defects of the dura with rhinoliquorrhoe.

Adult↗
PubMed2006

[Multidisciplinary management of skull base and craniocervical chordoma].

BACKGROUND: Craniocervical chordomas often only become manifest in an advanced stage. The localisation and locally-destructive growth require a multidisciplinary diagnostic and therapeutic concept early on. The goal of the present study was to present a reproducible strategy for quality assurance. PATIENTS AND METHOD: We retrospectively analysed the hospital records of 10 consecutive patients (4 women and 6 men) whom we had treated during a period of 7 years. RESULTS: The first step in therapy was tumour resection in 9 cases. One patient initially underwent stereotactic radiation. Postoperative radiation was not included a priori, but discussed individually depending on the degree of resection, the patient's age and physical condition. After an average 5 years follow up, 100 % of patients are alive. In all patients, tumour control was achieved. CONCLUSIONS: The prognosis for patients with chordomas of the skull base has improved considerably in recent years. New technologies like intraoperative navigation and improved radiation procedures have contributed to this improvement. The basis for treatment remains, however, the greatest possible surgical exstirpation with minimal surgical morbidity. Special attention should be paid in this connection to the stability of the cervical spine and the craniocervical transition border. In advanced tumour growth, complete resection is often not possible. Proton and heavy-ion radiation are promising new forms of therapy, which can also be applied after conventional radiation has been performed. A directed multidisciplinary procedure guarantees years of survival with good quality of life in many cases.

Adult↗
PubMed2006

[Reconstruction of tumor induced defects in head and neck surgery with individualized prefabricated three dimensional flaps with the use of continuous vacuum therapy].

Despite recent developments in oncologic head and neck surgery extensive tissue and functional defects following radical tumor resections remains a surgical challenge. Individually prefabricated free flaps to meet the needs of the functional defect can be generated with the help of continuous computer-assisted vacuum therapy. This accelerates the pre-fabrication of three-dimensional composite flaps and enhances therapeutic safety. Changes of the genuine structure of such flaps are induced by implantation of autologous or heterologous transplants alone or in combination with alloplastic materials as a supportive element. Application of vacuum therapy is useful to accelerate the process of pre-fabrication by the induction of angiogenesis. Besides this the continuous removal of wound exudate, possible seroma or haematoma and secondary compression of the different tissue layers improve the modelling of the three-dimensional construct. This article describes the technique of vacuum therapy for the pre-fabrication of three-dimensional pedicled or free flaps for reconstruction of defects after tumor resection in the head and neck area.

Absorbable Implants↗
PubMed2006

International trends in admissions and drug sales for asthma.

OBJECTIVE: To test whether national patterns of asthma drug use, particularly inhaled corticosteroids (ICS), are related to the rate of acute severe asthma exacerbations. DESIGN: The relation of international trends in hospital admissions for asthma with asthma drug sales was examined using country-specific regressions over the period 1990-1999. Pooled estimates of the regression coefficients were calculated using random effects models. RESULTS: Data on asthma admissions and asthma drug sales (including the sub-category ICS) were obtained from 11 countries. There was a negative relationship between falling admissions and rising sales of respiratory drugs and ICS in 9 of these 11 countries. A pooled estimate of the change in asthma admission rate per 10,000 associated with a unit increase in sales rate was -6.3 (95% CI -10.4 - -2.3) for all asthma drugs and -11.2 (95% CI -19.7 - -2.8) for ICS. CONCLUSION: At the national level, there is good evidence that over the last decade, increased sales of asthma drugs, and ICS in particular, were associated with a decline in rates of hospital admission for asthma. This is consistent with a beneficial effect of increasing use of asthma drugs, but other explanations such as decreasing prevalence could also be responsible.

Adolescent↗
PubMed2005

A congenital teratoma with a cleft palate: report of a case.

Teratomas are benign tumors containing cells from ectodermal, mesodermal and endodermal layers. They occur in about 1 in every 4000 births and most commonly in the sacrococcygeal region, followed by the ovaries. Congenital epignathus teratomas are rare embryological neoplasms localised in the region of head and neck. An epignathus is found in approximately 1:35,000 to 1:200,000 live births. This accounts for 2-9% of all teratomas. Size and location of the neoplasm in the oronasopharynx is variable. Teratomas are partly undiagnosed at the time of birth. They may exist with an intracranial extension or as small polyps. Large epignathi can lead to difficult management during and after birth. The case of a newborn girl with a combination of an epignathus and a cleft palate is described. The epignathus presented as a huge mass extending out of the mouth of the infant girl. On the day of birth debulking of the extraoral portion of the tumor, followed by intraoral exstirpation, was performed. The results of the histologic examination indicated a congenital epignathus. Six months later a recurrence was found.

Cleft Palate↗
PubMed2005

The free vastus lateralis flap for reconstruction in ablative oncologic head and neck surgery.

AIMS: The vastus lateralis muscle is an accessory extensor for the knee suitable as a free myocutaneous flap in reconstructive head and neck surgery. We report the use of this muscle as a flap. METHODS: We have used the free myocutaneous vastus lateralis flap for reconstruction following ablative head and neck tumour surgery in six patients. The clinical outcome, time of surgery for flap preparation and anatomosis, follow-up and functional outcome were analysed. RESULTS: Five of our patients showed a very satisfactory functional and cosmetic outcome. Post-operatively, there was no prolonged immobilisation and no limitation of movement to the hip and knee. No unfavourable side-effects at the donor side were noted. CONCLUSIONS: We find this flap a very useful addition to our free myocutaneous flap armamentarium. It has a specific suitability for replacing large defects.

Aged↗
PubMed2005

Polymorphism in neuropeptide Y influences CSF cholesterol levels but is no major risk factor of Alzheimer's disease.

Neuropeptide Y (NPY) is a neurotransmitter expressed in the central nervous system and involved in learning and memory. The NPY L7P polymorphism has been associated with altered cholesterol levels in obese patients. Since altered cholesterol metabolism is also involved in Alzheimer's disease (AD), the effects of two NPY polymorphisms (L7P and IVS1-100 T/G) on CSF and plasma cholesterol and 24S-hydroxycholesterol were investigated in AD patients and non-demented controls. Furtheremore, the effect of both NPY polymorphisms on the risk of AD was studied. The NPY IVS1-100 T/G polymorphism influenced CSF levels of cholesterol, whereas CSF and plasma levels of 24S-hydroxycholesterol and plasma cholesterol were not altered by genotype. NPY L7P polymorphism did not influence CSF or plasma cholesterol or 24S-hydroxycholesterol. Both NPY polymorphisms did not influence the risk of AD. Our data support the observation, that NPY polymorphisms might influence cholesterol metabolism, but might not act as major risk factor in AD.

Aged↗
PubMed2005

Management and outcome of patients with established coronary artery disease: the Euro Heart Survey on coronary revascularization.

AIMS: The purpose of the Euro Heart Survey Programme of the European Society of Cardiology is to evaluate to which extent clinical practice endorses existing guidelines as well as to identify differences in population profiles, patient management, and outcome across Europe. The current survey focuses on the invasive diagnosis and treatment of patients with established coronary artery disease (CAD). METHODS AND RESULTS: Between November 2001 and March 2002, 7769 consecutive patients undergoing invasive evaluation at 130 hospitals (31 countries) were screened for the presence of one or more coronary stenosis >50% in diameter. Patient demographics and comorbidity, clinical presentation, invasive parameters, treatment options, and procedural techniques were prospectively entered in an electronic database (550 variables+29 per diseased coronary segment). Major adverse cardiac events (MACE) were evaluated at 30 days and 1 year. Out of 5619 patients with angiographically proven coronary stenosis (72% of screened population), 53% presented with stable angina while ST elevation myocardial infarction (STEMI) was the indication for coronary angiography in 16% and non-ST segment elevation myocardial infarction or unstable angina in 30%. Only medical therapy was continued in 21%, whereas mechanical revascularization was performed in the remainder [percutaneous coronary intervention (PCI) in 58% and coronary artery bypass grafting (CABG) in 21%]. Patients referred for PCI were younger, were more active, had a lower risk profile, and had less comorbid conditions. CABG was performed mostly in patients with left main lesions (21%), two- (25%), or three-vessel disease (67%) with 4.1 diseased segments, on average. Single-vessel PCI was performed in 82% of patients with either single- (45%), two- (33%), or three-vessel disease (21%). Stents were used in 75% of attempted lesions, with a large variation between sites. Direct PCI for STEMI was performed in 410 cases, representing 7% of the entire workload in the participating catheterization laboratories. Time delay was within 90 min in 76% of direct PCI cases. In keeping with the recommendations of practice guidelines, the survey identified under-use of adjunctive medication (GP IIb/IIIa receptor blockers, statins, and angiotensin-converting enzyme-inhibitors). Mortality rates at 30 days and 1 year were low in all subgroups. MACE primarily consisted of repeat PCI (12%). CONCLUSION: The current Euro Heart Survey on coronary revascularization was performed in the era of bare metal stenting and provides a global European picture of the invasive approach to patients with CAD. These data will serve as a benchmark for the future evaluation of the impact of drug-eluting stents on the practice of interventional cardiology and bypass surgery.

Angina, Unstable↗
PubMed2005

Influence of peroxisome proliferator-activated receptor gamma gene polymorphism on 24S-hydroxycholesterol levels in Alzheimer's patients.

The peroxisome proliferator-activated receptor gamma (PPARgamma) is a nuclear hormone receptor, that is involved in lipid and glucose metabolism, which both seem to influence the risk of Alzheimer's disease (AD). 24S-Hydroxycholesterol is the major cholesterol elimination product of the brain and plasma and CSF 24S-hydroxycholesterol levels are altered in patients with neurodegenerative diseases. We investigated the effect of the common Pro12Ala variant of the PPARgamma gene on plasma cholesterol levels and 24S-hydroxycholesterol/ cholesterol ratios in 124 AD patients and 77 healthy controls. Furthermore, the influence of PPARgamma polymorphism on the risk of AD in 247 AD patients and 324 healthy controls was investigated. We found that PPARgamma Pro12Ala polymorphism influenced plasma 24S-hydroxycholesterol/ cholesterol ratios in AD patients in that carriers of the Ala allele presented with higher ratios than homozygote carriers of the Pro-allele. PPARgamma polymorphism did not influence the risk of AD. These results might point to an influence of PPARgamma Pro12Ala polymorphism on the elimination of 24S-hydroxycholesterol.

Aged↗