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A Dietz

Publications and source records attributed to A Dietz.

At least 55 records · Page 3Linked to original sources
PubMed2002

[Orbital floor reconstruction. Comparison of a new perforated 0.15 mm thick PDS layer with established titanium dynamic mesh].

INTRODUCTION: For surgical reconstruction of the orbital floor after blow-out fractures, a new perforated PDS (poly-p-dioxanon) foil (0.15 mm thickness) has recently become available. The main target of this prospective and randomized interdisciplinary clinical study was to compare this new PDS foil with the proven titanium dynamic mesh (0.3 mm thickness). PATIENTS/METHODS: Aside from the common diagnostic procedures, an extensive ophthalmologic examination was performed and documented preoperatively (U1), 4 days (U3), 1 month (U4), and 6 months (U5) postoperatively. RESULTS: In both groups the surgical procedure was tolerated well. The new perforated PDS foil turned out to be easier to handle intraoperatively because of smooth and clean cutting edges. The surgical treatment was well tolerated in all randomized groups. In contrast to the control group, the PDS and TD groups showed postoperatively a slight increase of the preoperative exophthalmos (mean 0.5 mm). CONCLUSION: The new perforated PDS foil is comparable concerning cosmetic and functional aspects. Especially with regard to stability after blow-out fractures, the new perforated PDS foil is equal to titanium dynamic mesh up to 20 mm in diameter. PDS foil is felt to be superior regarding bioresorption and due to the more convenient handling.

Adolescent↗
PubMed2001

Intensified hyperfractionated accelerated radiotherapy limits the additional benefit of simultaneous chemotherapy--results of a multicentric randomized German trial in advanced head-and-neck cancer.

PURPOSE: To demonstrate the efficacy of radiochemotherapy (RCT) as the first choice of treatment for advanced unresectable head-and-neck cancer. To prove an expected benefit of simultaneously given chemotherapy, a two-arm randomized study with hyperfractionated accelerated radiochemotherapy (HF-ACC-RCT) vs. hyperfractionated accelerated radiotherapy (HF-ACC-RT) was initiated. The primary endpoint was 1-year survival with local control (SLC). METHODS AND MATERIALS: Patients with Stage III and IV (UICC) unresectable oro- and hypopharyngeal carcinomas were randomized for HF-ACC-RCT with 2 cycles of 5-FU (600 mg/m(2)/day)/carboplatinum (70 mg/m(2)) on days 1--5 and 29--33 (arm A) or HF-ACC-RT alone (arm B). In both arms, there was a second randomization for testing the effect of prophylactically given G-CSF (263 microg, days 15--19) on mucosal toxicity. Total RT dose in both arms was 69.9 Gy in 38 days, with a concomitant boost regimen (weeks 1--3: 1.8 Gy/day, weeks 4 and 5: b.i.d. RT with 1.8 Gy/1.5 Gy). Between July 1995 and May 1999, 263 patients were randomized (median age 56 years; 96% Stage IV tumors, 4% Stage III tumors). RESULTS: This analysis is based on 240 patients: 113 patients with RCT and 127 patients with RT, qualified for protocol and starting treatment. There were 178 oropharyngeal and 62 hypopharyngeal carcinomas. Treatment was tolerable in both arms, with a higher mucosal toxicity after RCT. Restaging showed comparable nonsignificant different CR + PR rates of 92.4% after RCT and 87.9% after RT (p = 0.29). After a median observed time of 22.3 months, l- and 2-year local-regional control (LRC) rates were 69% and 51% after RCT and 58% and 45% after RT (p = 0.14). There was a significantly better 1-year SLC after RCT (58%) compared with RT (44%, p = 0.05). Patients with oropharyngeal carcinomas showed significantly better SLC after RCT (60%) vs. RT (40%, p = 0.01); the smaller group of hypopharyngeal carcinomas had no statistical benefit of RCT (p = 0.84). For both tumor locations, prophylactically given G-CSF was a poor prognostic factor (Cox regression), and resulted in reduced LRC (log-rank test: +/- G-CSF, p = 0.0072). CONCLUSION: With accelerated radiotherapy, the efficiency of simultaneously given chemotherapy may be not as high as expected when compared to standard fractionated RT. Oropharyngeal carcinomas showed better LRC after HF-ACC-RCT vs. HF-ACC-RT; hypopharyngeal carcinomas did not. Prophylactic G-CSF resulted in an unexpected reduced local control and should be given in radiotherapy regimen only with strong hematologic indication.

Adult↗
PubMed2001

Intraoperative B-mode endosonography of tongue carcinoma.

BACKGROUND: Exact estimation of a tumor's size and definition of adequate resection margins in carcinomas of the tongue are often difficult because of the tumor's extension and deep infiltration. METHODS: We developed a method that allows intraoperative visualization and marking of tumor margins: intraoperative endosonography was performed in five patients with carcinomas of the tongue with an 8- to 12-MHz linear array transducer. The oral cavity was flooded with normal saline solution, and the transducer was immersed therein. This allowed scanning in a noncontact mode. The tumor margins were marked with a surgical suture under endosonographic monitoring. RESULTS: In the five patients studied, histologic margins corresponded to sonographic margins. The sonographic marking proved to be useful during the resection of the tumor, and histologic safety margins were respected in each case. CONCLUSIONS: This noninvasive procedure provides a quick and reliable orientation during resection of tongue carcinoma, and a more precise and individual definition of resection margins is possible. Intraoperative noncontact use of endosonography is a promising method, and further studies may confirm this.

Adult↗
PubMed2001

Predictive value of the tumor oxygenation by means of pO2 histography in patients with advanced head and neck cancer.

PURPOSE: The purpose of this analysis was to evaluate the potential of the tumor oxygenation by means of Eppendorf pO2 histography as a predictive test to select patients for treatment alternatives. PATIENTS AND METHODS: Pretreatment tumor pO2 histographies of locoregional lymph node metastases were assessed in 194 patients with squamous cell carcinoma of the head and neck. Included in the analysis were 134 patients who received a primary radio- or radiochemotherapy with a radiation dose of > or = 60 Gy, and who had no distant metastasis at beginning of the therapy. RESULTS: The Cox regression analysis revealed the fraction of pO2 values < or = 2.5 mm Hg (p = 0.004), age (p = 0.04) and radiotherapy/radiochemotherapy (p = 0.03) as significant independent prognostic factors for the survival. The positive and negative predictive values were calculated using different cut-off values of the fraction of pO2 values < or = 2.5 mm Hg and the survival status at 1 or 2 years after beginning of the therapy as endpoint. The highest positive and negative predictive values of all cut-off values were 0.50 and 0.41 at 1 year, and 0.81 and 0.26 at 2 years. CONCLUSIONS: Our data confirm the influence of the tumor oxygenation on the prognosis of patients with squamous cell carcinoma of the head and neck after radiotherapy. However, the calculated positive and negative predictive values suggest that the pO2 histography alone is not sufficient to be used as a predictive test to successfully select patients for treatment alternatives.

Adult↗
PubMed2001

Effectiveness of a new perforated 0.15 mm poly-p-dioxanon-foil versus titanium-dynamic mesh in reconstruction of the orbital floor.

Introduction: In recent years a new perforated PDS (poly-p-dioxanon) foil (0.15 mm) has become available and has not yet been proven to be successful in reconstruction of the orbital floor after blow-out-fractures in randomized studies. The main aim of this clinical trial is to compare this new PDS foil with titanium dynamic mesh (0.3 mm) (TD), which is well established in reconstruction of the orbital floor. Patients and Methods: In a prospective multicentre randomized trial, conducted between 1997 and 1998, out of 42 patients with fractures of the orbital floor, 28 patients needing material for reconstruction were randomized to receive either PDS foil or TD. In a comprehensive preoperative and postoperative protocol patients were monitored by the surgeon, radiologist and ophthalmologist with a postoperative follow-up of least 6 months. Results: Maximum defects of the orbital floor were comparable in both groups (PDS group: 13.3 mm, TD group: 13.9 mm). In both groups the surgical procedure was well tolerated, and functional and cosmetic results were evaluated as satisfactory by all patients. Ophthalmological evaluation, performed up to 6 months postoperatively, revealed double vision or vertical strabismus in nine patients (five PDS group, four titanium group). This was not confirmed subjectively in each single patient. Also ex- or enophthalmos, registered in seven patients of the PDS and four of the TD group (mainly +/-1 mm) were not considered as relevant by the patients. Conclusion: The new 0.15 mm perforated PDS foil was comparable to 0.3 mm titanium mesh concerning functional and cosmetic outcome. Obviously, persisting ophthalmometric disorders were compensated very well in both groups. PDS foil is felt to be the preferred material since it is bioresorbable and more convenient to handle. Copyright 2001 European Association for Cranio-Maxillofacial Surgery.

Journal Article↗
PubMed2001

Angiographic correlates of a positive troponin T test in patients with unstable angina.

OBJECTIVE: To study the angiographic correlates of cardiac troponin T (cTnT)-positive and -negative patients with unstable angina pectoris. BACKGROUND: A positive cTnT test identifies a high-risk subgroup of unstable angina pectoris patients. Only the high-risk cTnT-positive patients seem to benefit from a more aggressive antithrombotic treatment regimen. The underlying coronary pathology in cTnT-positive and -negative patients that explains the predictive power of cTnT on prognosis and response to antithrombotic therapy is largely unknown. METHODS: A total of 197 subsequently admitted patients with unstable angina pectoris underwent cTnT testing by a rapid bedside assay and early qualitative and quantitative angiography. Long-term follow-up was 12 months. RESULTS: Patients with cTnT-positive tests revealed more critical stenoses of culprit lesions (p =.041), more severe reductions of thrombolysis in myocardial infarction flow grades (p <.037), a higher prevalence of intracoronary thrombus (p =.079), and a poorer left ventricular function (p =.047). The odds ratio of cTnT was 5.8 (p <.0001) for presence of thrombus, reduced thrombolysis in myocardial infarction flow, and/or critical stenosis (>90%), and was 3.1 (p =.005) for presence of three-vessel disease, left main disease, and/or reduced left ventricular ejection fraction. Coronary bypass grafting was more frequently performed in the cTnT-positive group. However, event-free survival was not different in our cohort characterized by a high rate of percutaneous coronary interventions. CONCLUSIONS: A positive cTnT test in patients with unstable angina pectoris indicates presence of more severe coronary artery disease and poorer left ventricular function. This finding could explain the differences in short- and long-term outcome and treatment responses to antithrombotic regimens.

Aged↗
PubMed2001

Endovascular treatment of symptomatic carotid stenosis using stent placement: long-term follow-up of patients with a balanced surgical risk/benefit ratio.

BACKGROUND AND PURPOSE: Carotid endarterectomy (CEA) is not necessarily beneficial in all patients with symptomatic high-grade (>/=70%) internal carotid artery (ICA) stenosis. Independent risk factors modulate both the individual stroke risk under medical treatment and the combined stroke and death risk after CEA. Endovascular stenting of symptomatic ICA stenosis may be an alternative to CEA in patients with a balanced surgical risk/benefit ratio. METHODS: We included 43 patients (71% men; median age, 67 years) with a recently symptomatic ICA stenosis with >/=70% luminal narrowing in whom the individual sum of medical and surgical risk factors suggested a balanced surgical risk/benefit ratio (risk-modeling appraisal derived from the European Carotid Surgery Trial). After stenting of the stenosed ICA with distal balloon protection, the mean+/-SD follow-up, including clinical and ultrasonographic examinations, was 20+/-11.8 months, with a median number of examinations of 5 per patient. RESULTS: Recanalization of ICA stenoses was technically successful in 40 of 43 procedures (93%). Within the 30-day postinterventional period 1 death occurred (2.5%), and the combined stroke and death rate within follow-up was 5%. Except for 1 asymptomatic ICA occlusion, no restenosis >/=70% occurred during follow-up. CONCLUSIONS: ICA stenting in symptomatic patients with a balanced surgical risk/benefit ratio is technically feasible, with a low periprocedural risk of stroke or death. Furthermore, the risk of future stroke and rate of significant restenosis during long-term follow-up appears to be low, suggesting that ICA stenting may be useful in carotid revascularization and stroke prevention.

Aged↗
PubMed2001

Systemic and intracerebral infections of mice with Listeria monocytogenes successfully treated with linezolid.

Linezolid is an oxazolidinone derivative which is active mostly against Gram-positive bacteria. In this work its activity against the facultatively intracellular bacterium Listeria monocytogenes was examined in vitro, in tissue culture and in animal models of systemic and intracerebral infection and compared with ampicillin which is the antibiotic of choice for treatment of listeriosis. All strains of L. monocytogenes were susceptible to the substance, with minimal inhibitory concentrations (MICs) determined by E-test ranging from 0.38 to 1.5 mg/l which is below the preliminary breakpoint of this substance. Linezolid was bacteriostatic against L. monocytogenes since up to 64 times the MIC did not kill the bacteria in 24 hours. Linezolid was also bacteriostatic on L monocytogenes in infected tissue culture cells. In animal models of systemic and intracerebral infection, linezolid was able to inhibit bacterial growth but was clearly less effective than ampicillin. In conclusion, linezolid might be useful for the treatment of infections with L monocytogenes in humans when ampicillin may not be used.

Acetamides↗
PubMed2001

Overexpression of p53 in tumor-distant epithelia of head and neck cancer patients is associated with an increased incidence of second primary carcinoma.

Second primary carcinoma is a peculiar feature of head and neck cancer and represents a form of treatment failure distinct from the recurrence of the primary tumor. Whether altered p53 expression in tumor-distant epithelia at the time of diagnosis is of clinical value as a biomarker for second primary carcinoma development has not been rigorously answered because of the lack of long-term follow-up studies involving a sufficiently large patient cohort. In this prospective study, we have investigated p53 expression in tumor-distant epithelia and in the corresponding primary tumors of 105 head and neck cancer patients by immunohistochemistry on frozen sections. After a median follow-up of 55 months, the clinical course of disease parameters, i.e., local recurrences, lymph node and distant metastasis, incidence of second primary carcinoma, and survival, was evaluated. Overexpression of p53 in tumor-distant epithelia was found in 49 patients (46.7%), and it was independent of the p53 protein status of the primary tumor and of the tumor site, size, stage, and grading. Mucosal p53 overexpression was not associated with local primary recurrences, lymph node or distant metastases, or overall survival. Importantly, mucosal p53 overexpression, but not overexpression in the primary tumors, was significantly associated with an increased incidence of second primary carcinomas (P = 0.0001; Fisher's exact test). When the times to second primary tumor occurrence were analyzed by the Kaplan-Meier method, the difference remained significant (P = 0.005; log rank test). We conclude that IHC staining for p53 overexpression in tumor-distant epithelia provides a simple and rapid tool to identify head and neck cancer patients at increased risk of developing second primary tumors. Because p53 overexpression in these epithelia in our patient cohort was specifically associated with second primary cancer but not with recurrences, at least a fraction of the second primary cancers appears to have resulted from genetic events in the mucosa ("field cancerization").

Carcinoma, Squamous Cell↗
PubMed2001

Efficient treatment of murine systemic infection with Candida albicans using amphotericin B incorporated in nanosize range particles (emulsomes).

The effects of emulsome nanosize range lipid particles containing amphotericin B (EAmB) were compared with the reference formulation containing deoxycholate (Fungizone; Bristol-Myers Squibb, Munich, Germany) and with the commercial amphotericin lipid complex preparation (AmBisome; Nexstar, San Dimas, CA, USA). The minimal inhibitory concentrations of Fungizone and EAmB were identical although killing of Candida albicans was delayed when EAmB was used. In a tissue culture model and in mice, the incorporation of AmB into emulsomes resulted in a considerable reduction of toxicity in comparison with Fungizone. For comparison of the in vivo effect of the preparations a mouse model of systemic infection with C. albicans was used. All preparations were able to reduce the fungal burden in the liver and kidneys in comparison with control animals treated with isotonic saline. AmBisome was more efficient in the reduction of the fungal burden of the liver than EAmB and Fungizone, even when applied in a similar dosage of 1 mg kg(-1). In the kidneys, EAmB and Fungizone was slightly more effective than AmBisome. Therefore, in our models, the incorporation of AmB into nanosize particles was able to reduce toxicity without loss of efficiency. EAmB may be considered a candidate preparation for the treatment of infections with C. albicans in humans.

Amphotericin B↗
PubMed2001

Paranasal sinus mucormycosis: a report of two cases.

Mucormycosis of the nose and paranasal sinuses is a rare invasive fungal infection, which often has a very fulminant course and characteristic clinical findings. The patients are usually immunocompromised, with diabetic ketoacidosis being the commonest underlying disorder. In some immunocompetent patients, the disease is associated with local predisposing factors, such as chronic sinusitis. Although the prognosis has improved in recent decades, the disease can still be fatal. The underlying disease is an important determinant of prognosis and correction of the metabolic disorder, if present, is essential. Herein we report two cases: one of our patients was immunocompetent but had earlier suffered from polypous rhinosinusitis whereas the other had mild adult-type diabetes. Both patients were successfully treated with surgical debridement and amphotericin B.

Aged↗
PubMed2000

Prognostic relevance of serum levels of the angiogenic peptide bFGF in advanced carcinoma of the head and neck treated by primary radiochemotherapy.

BACKGROUND: The objective of this trial was to analyze the prognostic relevance of the angiogenic peptides basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), and matrix metalloproteinase-2 (MMP-2) in the serum of patients with advanced carcinoma of the head and neck treated by primary radiochemotherapy. METHODS: From 1992 to 1995, 26 patients with advanced head and neck cancer (25 stage IV, 1 stage III UICC) were treated according to the protocol of radiochemotherapy with carboplatin. The pretreatment serum levels VEGF, bFGF, and MMP-2 were measured by ELISA, and data were correlated with tumor characteristics and followed up (median time of follow up, 60 months). RESULTS: An increase in bFGF serum level above the upper limit of normal controls showed a significant correlation with shorter time the of locoregional control (p =.036). In covariant analysis bFGF serum concentration proved to be independent of other prognostic factors like tumor site, age, total tumor volume, and response to therapy. No prognostic relevance of VEGF and MMP-2 serum levels could be determined. CONCLUSIONS: The results of this pilot study indicate that the serum concentration of bFGF has prognostic relevance for advanced head and neck cancer.

Adult↗
PubMed2000

[Antimycotic therapy in otomycosis with tympanic membrane perforation].

Especially after prolonged antibiotic ototopic therapy otomycosis is not rare. An inoculation of fungi into the tympanic cavity however may have serious sequelae. Therefore an eradication of fungi from the external auditory canal is imperative before surgery. In addition to thorough cleaning of the outer ear canal antimycotic preparations are recommended in treating otomycosis. However, all of the commercially available ear drops contain ototoxic agents. In the case of defects of the tympanic membrane a damage of the inner ear may result. Alternatively, we suggest an aqueous solution of Miconazol 0,5%.

Administration, Topical↗
PubMed2000

[Herpes simplex virus type 1-induced rising dbl quote, left (low)tumor" in the nasal vestibule. The problem of resistance development of herpes simplex in a patient with chronic lymphatic B-cell leukemia].

Herpes simplex viruses are known to be among the most common disease-causing microorganisms. Their prevalence can exceed 90% depending on the socioeconomic status of the population. Since the number of immunocompromised patients has increased because of the increased incidence in the acquired immunodeficiency syndrome and an increase in organ transplantation, herpes virus infection may have a greater clinical significance. While treatment of otherwise healthy individuals will not usually cause any clinical problems herpes infection in an immunocompromised patient can have severe consequences. Additionally, development of viral resistance can be observed that may require alternative drugs in treatment. We present a case history of a man with a B-cell chronic lymphocytic leukemia that was associated with a very unusual herpes simplex virus infection in the nasal vestibule. Possible causes for the development of resistance in herpes infections and the use of famciclovir and forscarnet as two therapeutic alternatives to aciclovir are discussed.

Antiviral Agents↗
PubMed2000

[Detection of numerical chromosome aberrations in leukoplakia and squamous epithelial carcinomas of the head-neck area using fluorescence in situ hybridization].

The tumorigenesis of head and neck squamous cell carcinoma (HNSCC) has been proposed to represent a multistep process characterized by an accumulation of genetic alterations. To study numerical chromosomal aberrations and chromosomal imbalances, biopsies of 11 malignant tumours and biopsies of 16 oral premalignant lesions (leukoplakias) were analyzed by fluorescence in situ hybridization (FISH) using centromeric probes for chromosomes, 1, 7, 9, 10 and 17. The comparison of the alterations observed in simple leukoplakias (group 1, n = 8), dysplastic leukoplakias (group 2, n = 8) and malignant tumours (group 3, n = 11) by the Cochran-Armitage Trend Test revealed an increasing number of numerical chromosomal abberations. This difference was statistically highly significant (p < 0.001). The data open up the possibility that FISH analysis might help to better characterize the progression of premalignant oral leukoplakias.

Biopsy↗