[Crew resource management and simulator training in acute stroke therapy]. / Crew-Ressource-Management und Simulatortraining in der akuten Schlaganfalltherapie.

BACKGROUND: Time is of critical importance in acute stroke management. The establishment of thrombectomy now adds to the complexity and interdisciplinarity of the initial phase. In non-medical high-fidelity situations, such as aviation, crew resource management (CRM) has proven to be highly efficient. It has therefore also been implemented in professional cardiovascular life support training. In a setting where every minute counts, CRM and regular training of the high-fidelity stroke team could offer ways to improve treatment of acute stroke patients. OBJECTIVES: We evaluated the effects of a CRM-based stroke team with regular simulation training on the quality of care (e.g. door to needle time and thrombolysis rate) as well as on staff satisfaction and perceived patient safety in the emergency department of a tertiary care neurocenter. MATERIAL AND METHODS: We implemented a dedicated stroke team consisting of 7 persons who are notified by a collective call via speed dial and conceived a simulator-based team training for all new stroke team members which we conduct at monthly intervals. We recorded door to needle times of all consecutive patients, staff satisfaction in the emergency room and the acceptance of this new learning format. RESULTS: This approach led to a relevant and sustained reduction of the mean door to needle time to less than 30 min. It improved perceived patient safety in residents with professional experience of less than 2 years. There was a very high acceptance within the stroke team training and staff and its usefulness was judged to be very high. CONCLUSION: Even though our data do not allow positive effects on patient outcomes to be inferred, the implementation of a CRM-based stroke team and simulator training has had multiple positive effects on the workflow and work satisfaction in the treatment of acute stroke patients.

Indistinguishable photons from separated silicon-vacancy centers in diamond.

We demonstrate that silicon-vacancy (SiV) centers in diamond can be used to efficiently generate coherent optical photons with excellent spectral properties. We show that these features are due to the inversion symmetry associated with SiV centers. The generation of indistinguishable single photons from separated emitters at 5 K is demonstrated in a Hong-Ou-Mandel interference experiment. Prospects for realizing efficient quantum network nodes using SiV centers are discussed.

Multiple intrinsically identical single-photon emitters in the solid state.

Emitters of indistinguishable single photons are crucial for the growing field of quantum technologies. To realize scalability and increase the complexity of quantum optics technologies, multiple independent yet identical single-photon emitters are required. However, typical solid-state single-photon sources are inherently dissimilar, necessitating the use of electrical feedback or optical cavities to improve spectral overlap between distinct emitters. Here we demonstrate bright silicon vacancy (SiV(-)) centres in low-strain bulk diamond, which show spectral overlap of up to 91% and nearly transform-limited excitation linewidths. This is the first time that distinct single-photon emitters in the solid state have shown intrinsically identical spectral properties. Our results have impact on the application of single-photon sources for quantum optics and cryptography.

[Introduction of interdisciplinary prostate cancer centers based on the recommendations of the German Cancer Society. A cost-benefit analysis 3 years after accreditation]. / Etablierung von interdisziplinären Prostatakrebszentren nach den Empfehlungen der DKG. Eine Kosten-Nutzen-Analyse 3 Jahre nach Zertifizierung.

The introduction of prostate cancer treatment centers according to the criteria of the German Cancer Society ("Deutsche Krebsgesellschaft", DKG) aims at improving the quality of care for patients with prostate cancer. Systematic analyses of the effects and costs are lacking as yet. Three years after certification of the Interdisciplinary Prostate Cancer Center at the Charité Hospital Berlin we observed a decrease in the rate of positive surgical margins (tumor stage pT2), but other parameters of treatment quality including patient satisfaction remained unchanged. A survey among urologists of the region showed a high acceptance of prostate cancer centers in general. The majority of participating urologists appreciated the work of the Charité center, in particular the treatment recommendations given by the center were mostly followed and the majority of urologists regularly use educational activities of the center. However, only 30% of the participating urologists confirmed short-term improvements in the quality of patient care. Yearly additional costs for the Charité prostate cancer center are estimated at 205,000 euro (precertification phase and certification) and 138,000 euro (monitoring phase), despite the initial drop in mean treatment costs per case (radical prostatectomy). The introduction of prostate cancer treatment centers certified by the DKG is cost intensive, increases in treatment efficiency notwithstanding. Short-term improvements in quality of care cannot be unequivocally demonstrated. Prostate cancer centers serve an important role in counseling and medical education and may thus help disseminate evidence-based treatment strategies.

[Mucormycosis in paranasal sinuses]. / Mucormykosen der Nasennebenhöhlen.

Three patients with mucormycosis of the paranasal sinuses were treated in the University ENT departments in Bochum and Essen in recent years. All patients were immunocompromised for different reasons and had reduced resistance against microorganism infection. They presented with symptoms of orbital complications of sinusitis. The further progress of these life-threatening fungal infections with a mortality rate between 35 and 70% depends on early and definitive diagnosis and radical surgical therapy to reduce the amount of infectious agent. The difficulties of early diagnosis by imaging, histology, microbiology, or molecular biology and postoperative therapeutic options especially with amphotericin B, liposomal amphotericin B, and posaconazole are illustrated and discussed.

Primary CNS lymphoma with intraocular involvement: International PCNSL Collaborative Group Report.

OBJECTIVE: To describe the demographics, diagnostic details, therapeutic management, and outcome in patients with primary CNS lymphoma (PCNSL) with ocular involvement. METHODS: A retrospective study of 221 patients was assembled from 16 centers in seven countries. Only HIV-negative, immunocompetent patients with brain and ocular lymphoma were included; none had systemic lymphoma. RESULTS: Median age at diagnosis was 60. Fifty-seven percent were women. Median Eastern Cooperative Oncology Group performance status was 2. Ocular disturbance and behavioral/cognitive changes were the most common presenting symptoms. Diagnosis of lymphoma was made by brain biopsy (147), vitrectomy (65), or CSF cytology (11). Diagnosis of intraocular lymphoma was made by vitrectomy/choroidal/retinal biopsy (90) or clinical ophthalmic examination (141). CSF cytology was positive in 23%. Treatment information was available for 176 patients. A total of 102 received dedicated ocular therapy (ocular radiotherapy 79, intravitreal methotrexate 22, and both 1) in addition to treatment for their brain lymphoma. Sixty-nine percent progressed at a median of 13 months; sites of progression included brain 52%, eyes 19%, brain and eyes 12%, and systemic 2%. Patients treated with local ocular therapy did not have a statistically significant decreased risk of failing in the eyes (p = 0.7). Median progression free survival and overall survival for the entire cohort were 18 and 31 months. CONCLUSION: This is the largest reported series of primary CNS lymphoma (PCNSL) with intraocular involvement. Progression free and overall survival was similar to that reported with PCNSL. Dedicated ocular therapy improved disease control but did not affect overall survival.

[Cutaneous basosquamous cell carcinoma]. / Basosquamöses Karzinom der Haut.

BACKGROUND: Basosquamous carcinoma (BSC) is a rare malignancy with specific histopathological features of both basal cell (BCC) and squamous cell carcinoma (SCC). Therefore, the histological diagnosis is challenging. Due to its low incidence there is no consensus on the surgical management of BSC. PATIENTS AND METHODS: We describe the (immunohistological) diagnostic and therapeutic aspects of nine cases (8 male symbol : 1 female symbol, on average 68.6 years of age (range: 47-81)) of BSC. Of these, seven were located on the pinna, one on the forehead and zygomatic region and one in the retroauricular region. RESULTS: Immunochemical staining for epithelial membrane antigen was negative (apart from the typical areas of epithelial pearl formation) and BerEP4 was positive in all cases. Therapy consisted of partial removal of the pinna in four, and total removal in three cases. One patient was treated by partial removal of the auricle with superficial parotidectomy and ipsilateral neck dissection. In the case of the carcinoma on the forehead, a local excision was performed. The median follow-up was 45 months. One patient had a local recurrence. CONCLUSIONS: The histological diagnosis of BSC is confirmed by the use of EMA and BerEP4 immunohistological staining. Clinically, BSC is a rare, aggressive skin tumor. Despite the histological similarity to basal cell carcinoma, BSC has an imminent risk of metastasizing. Hence, therapy should be similar to that for SCC, taking into consideration the age and general state of the usually elderly patient.

[Patients' satisfaction after nasal septal and turbinate surgery. Results of a questionnaire]. / Ergebnisse einer Umfrage zur Patientenzufriedenheit nach Nasenseptumplastik und Muschelbehandlung.

INTRODUCTION: Regarding the satisfaction of patients efficiency and outcome of surgery on the nasal septum and the turbinates regularly is the topic of controversial discussion and occasionally some health authorities doubt there is an indication for these procedures in general. Subjective and objective evaluation of surgical outcome do not necessarily match in all cases. METHODS: A standardized questionnaire was sent to patients having undergone surgery on the nasal septum and the turbinates 33-45 months ago at a university hospital and a non-university hospital. Topics (10 all together) were e. g.: nasal aeration, sense of smell, rhinorrhea, snoring, general condition. Statistic significance of each parameter was verified. RESULTS: 138 questionnaires were reviewed. 82% of the candidates reported better aeration of the nose after surgery. 71% stated to have benefited from the operation. A relevant positive effect on snoring, rhinorrhea, headache and sense of smell could not be proved. The results did no different whether surgery was performed at a university hospital or at a non-university-hospital. Older patients seem to profit more from the procedure than younger ones. DISCUSSION: The survey clearly shows, that surgery on the nasal septum with turbinoplasty has a positive effect on the nasal aeration and the general condition. Therefore its performance is well justified when after careful verification of the pre-conditions the indication for surgery is given.

Primary intraocular lymphoma: an International Primary Central Nervous System Lymphoma Collaborative Group Report.

BACKGROUND: Primary intraocular lymphoma (PIOL) is an uncommon subset of primary central nervous system lymphoma. Because it is rare and difficult to diagnose, the natural history and optimal management are unknown. PATIENTS AND METHODS: A retrospective study of 83 HIV negative, immunocompetent PIOL patients was assembled from 16 centers in seven countries. RESULTS: Median age at diagnosis was 65. Median ECOG performance status was 0. Presenting symptoms included blurred vision, decreased visual acuity, and floaters. Median time to diagnosis was 6 months. Diagnosis was made by vitrectomy (74), choroidal/retinal biopsy (6) and ophthalmic exam (3). Eleven percent had positive CSF cytology. Initial treatment was categorized as focal in 23 (intra-ocular methotrexate, ocular radiotherapy) or extensive in 53 (systemic chemotherapy, whole brain radiotherapy). Six received none; details are unknown in one. Forty-seven relapsed: brain 47%, eyes 30%, brain and eyes 15%, and systemic 8%. Median time to relapse was 19 months. Focal therapy alone did not increase risk of brain relapse. Median progression free (PFS) and overall survival (OS) were 29.6 and 58 months, respectively, and unaffected by treatment type. CONCLUSION: Treatment type did not affect relapse pattern, median PFS or OS. Focal therapy may minimize treatment toxicity without compromising disease control.

[Accelerated hyperfractionated radiotherapy with concurrent chemotherapy in locally advanced nasopharyngeal carcinomas]. / Lokal fortgeschrittene Nasopharynxkarzinome. Hyperfraktioniert-akzelerierte Radiotherapie mit simultaner Chemotherapie.

BACKGROUND: The excellent results yielded by hyperfractionated and accelerated radiotherapy associated with concurrent chemotherapy in locally advanced oropharyngeal and hypopharyngeal carcinomas led to investigation of this therapeutic regimen in nasopharyngeal carcinomas also. METHODS: Thirty-five patients with stage III and IV nasopharyngeal carcinomas received accelerated hyperfractionated radiotherapy with concurrent chemotherapy (5-FU, mitomycin C + leucovorin). In the first 3 weeks of treatment five 2-Gy doses per week were delivered to the primary tumour and regional lymph nodes. The fractionation was then accelerated, with 1.4 Gy given twice daily until a total dose of 72 Gy had been administered. RESULTS: The overall objective response rate was 100%. The median follow-up period was 71 months. Salvage surgery of the lymph nodes was performed in 10 patients, revealing vital tumour tissue in 6 of these. The actuarial 5-year local control rate was 64% (95%CI: 47-81%), while overall actuarial survival at 5 years was 70% (95%CI: 53-86%). CONCLUSION: Hyperfractionated accelerated radiotherapy with concurrent chemotherapy is effective and feasible in locally advanced nasopharyngeal carcinoma.

[Wegener's granulomatosis and orbital complications of sino-nasal origin]. / Zur sinugenen orbitalen Komplikation bei Morbus Wegener.

Wegener's granulomatosis is an idiopathic, granulomatous disease with the potential for multiple head and neck manifestations (80 % of the patients). Sinonasal symptoms are observed in more than 60 % of the patients. Due to these facts the otorhinolaryngologist plays an essential role in the multidisciplinary team involved in establishing the diagnosis early, initiating immunosuppressive therapy and providing ongoing care. The treatment is based on medical therapy consisting of corticosteroids and immunosuppressive agents, whereas surgery is reserved for selected head and neck manifestations. By means of 3 patients presenting with distinct visual loss in consequence of orbital complications with sinonasal origin the course of disease and theoretical background are reviewed. In our patients Wegener's granulomatosis was diagnosed by histopathological examination and serological detection of ANCA, cANCA. The progression of the granulomatous process and an additional purulent inflammation in 2 cases led to a temporary amaurosis and in another case to a visual loss of 50 %. Immediate orbital decompression in combination with sufficient systemic immunosuppressive treatment relieved the compression of the optical nerve and preserved vision. We conclude that early orbital decompression either by external or endonasal approach and concomitant immunosuppression is necessary to determine or improve rapidly decreasing vision subsequent to high intraorbital pressure produced by a granulomatous process and inflammation.

[Management of iatrogenic esophageal perforations]. / Management iatrogener Osophagusperforationen.

BACKGROUND: Iatrogenic esophageal perforations are still a life-threatening clinical entity. PATIENTS AND RESULTS: We present the case reports of six patients to demonstrate different treatment options and we focus on new therapeutic strategies which have evolved in the interdisciplinary management of iatrogenic esophageal perforations. Two patients with perforations in the cervical esophagus were operated and in another patient the perforation was closed with fibrin glue. Three patients with perforations in the thoracic esophagus were treated with self-expandable plastic stents. CONCLUSION: The surgical therapy of esophageal perforations still is regarded to be the gold standard and nonadherence should only be considered based on interdisciplinary decisions in individual cases. However, positive results are increasingly being reported for conservative endoscopic treatment, particularly for thoracic perforations.

[Prosthetic supply of tissue defects in head and neck surgery]. / Epithetische Versorgung von Gewebedefekten in Kopfbereich.

BACKGROUND: Cancer surgery, malformation or trauma may cause broad facial defects that cannot be covered by patients because of their exposed site. Such defects lead to functional deficits and enormous psychological strain and require rehabilitation at all ages. Prosthetic supply has been developed into a functional and aesthetic alternative to plastic and reconstructive surgery. METHODS AND PATIENTS: The condensed experience with prosthetic supply after persistent surgical defects of more than twenty patients during the recent years is described. RESULTS: Efficient prosthetic supply in the exposed facial area requires a well scheduled and close cooperation between the surgeon and anaplastologist. Preoperative diagnostic evaluation and operative filling of the magnetic fixation in cooperation with the anaplastologist provide a satisfying functional and cosmetic prosthetic outcome for the patient. Advantages of this procedure combine early cosmetic rehabilitation with the option to directly investigate the tumor site after resection. Novel magnet systems provide a high degree of flexibility combined with confident fixation. CONCLUSIONS: Prosthetic rehabilitation should be offered and discussed with patients ahead of cancer surgery in the head and neck area. This procedure should be considered in particular in patients that reject or are not feasible for multi-step reconstructive surgery.

Prospective trial on topotecan salvage therapy in primary CNS lymphoma.

BACKGROUND: Standard salvage therapy has not been established for recurrent primary central nervous system lymphoma (PCNSL). We report the final results of a prospective study on topotecan chemotherapy in relapsed or refractory PCNSL. PATIENTS AND METHODS: The study included 27 patients with a median age of 51 years and an ECOG performance status of 2. Fourteen patients were refractory to the last therapy, and 13 relapsed after a median period of 6.0 months. Pretreatment with up to four regimens included chemotherapy in 26 patients and whole brain irradiation in 14. A 30-min daily topotecan infusion of 1.5 mg/m(2) for 5 days was repeated every 3 weeks. RESULTS: The response rate was 33% with five complete (CR) and four partial remissions (PR). The median follow-up was 37.7 months. All complete responders had sustained remissions lasting for 9 to 28 months. The median event-free survival (EFS) was 2.0 months (9.1 months in responders), the overall survival (OAS) was 8.4 months. CTC grade 3-4 leukopenia occurred in 26% and thrombocytopenia in 11% of the patients. Eight of 12 patients alive without cerebral lymphoma > or = six months after topotecan exhibited deficits attributable to late neurotoxicity. CONCLUSION: Topotecan as monotherapy is active in relapsed and refractory PCNSL with tolerable toxicity.

[Osteosynthesis in facial bones: silicon nitride ceramic as material]. / Osteosynthese im Gesichtsschädelbereich: Siliziumnitritkeramik als Werkstoff.

BACKGROUND: The favorable properties of silicon nitride (Si3N4) ceramic, such as high stability and biocompatibility suggest its biomedical use as an implant material. The aim of this study was to test its suitability for osteosynthesis. MATERIALS AND METHODS: A Si3N4 prototype minifixation system was manufactured and implanted for osteosynthesis of artificial frontal bone defects in three minipigs. After 3 months, histological sections, CT and MRI scans were obtained. Finite element modeling (FEM) was used to simulate stresses and strains on Si3N4 miniplates and screws to calculate survival probabilities. RESULTS: Si3N4 miniplates and screws showed satisfactory intraoperative workability. There was no implant loss, displacement or fracture. Bone healing was complete in all animals and formation of new bone was observed in direct contact to the implants. CONCLUSIONS: Si3N4 ceramic showed a good biocompatibility outcome both in vitro and in vivo. This ceramic may serve as biomaterial for osteosynthesis, e.g. of the midface including reconstruction of the floor of the orbit and the skull base. Advantages compared to titanium are no risk of implantation to bone with mucosal attachment, no need for explantation, no interference with radiological imaging.

Post-tonsillectomy haemorrhage: a retrospective comparison of abscess- and elective tonsillectomy.

CONCLUSION: There is no increased risk of postoperative haemorrhage for abscess tonsillectomies in comparison to elective tonsillectomies. OBJECTIVE: There is still controversy as regards the optimal management of peritonsillar abscess. Opponents of tonsillectomy à chaud cite an increased postoperative bleeding risk. Most authors who compared the risks of postoperative haemorrhage after tonsillectomy à chaud and tonsillectomy à froid did not take into consideration criteria such as the age and gender of the patients or the experience of the surgeon. We aimed to eliminate this bias by performing a retrospective study in which a large series of abscess tonsillectomies were compared with an age- and gender-matched group of elective tonsillectomies. MATERIAL AND METHODS: All patients had been operated on at the Department of Otorhinolaryngology, University of Duisburg-Essen between March 1994 and August 2000. There were 350 patients in the abscess tonsillectomy group (61% male, 39% female; mean age 31.8 years; range 3-88 years) and 311 in the elective tonsillectomy comparison group (61% male, 39% female; mean age 30.0 years; range 2-83 years). RESULTS: In the abscess tonsillectomy group, 9 patients (2.6%; confidence level 1.1-4.8%) had postoperative haemorrhages which required treatment under general anaesthesia, compared to 17 (5.5%; confidence level 3.2-8.6%) in the age- and gender-matched group of "selected" elective tonsillectomies. The difference between these two rates was not significant (p = 0.056). The fairly high rate of haemorrhages in the elective tonsillectomy group was mainly due to the effect of the age-matching procedure, which excluded a considerable number of usually unproblematic tonsillectomies for tonsillar hyperplasia in young children. Moreover, our results show that there is a learning curve for surgeons performing tonsillectomies with regard to postoperative haemorrhages.

Pharmacokinetics and efficacy of ifosfamide or trofosfamide in patients with intraocular lymphoma.

BACKGROUND: The prognosis of intraocular lymphoma (IOL) is poor, and the optimal treatment has not yet been defined. The study assesses ifosfamide (IFO) and trofosfamide (TRO) for treating IOL. PATIENTS AND METHODS: We prospectively evaluated the efficacy and aqueous penetration of intravenous IFO, oral TRO and their active 4-hydroxy (4-OH) metabolites in 10 patients with IOL. Doses varied from 1500 to 2000 mg/m2/day on days 1-3 for IFO and from 150 to 400 mg/day (continuous or intermittent administration) for TRO. Four patients had newly diagnosed disease, and six had relapsed after pretreatment. RESULTS: All patients responded to first treatment with IFO or TRO, and both of two patients responded to re-treatment with IFO on ocular relapse. Progression-free survival from the first treatment with IFO or TRO was > or = 6-18 months. In six of six patients, 4-OH metabolites were detected in the aqueous humor at a concentration of 0.32-1.56 microM immediately after IFO infusion with an aqueous/serum ratio of 0.19-0.54. 4-OH metabolites could be detected in one of three patients at a concentration of 7.2 microM 3-16 h after ingestion of TRO. CONCLUSIONS: IFO and TRO are active in IOL. IOL patients evidence aqueous penetration of 4-OH metabolites after intravenous administration of IFO.