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In the present article, interactions associated with magnetic resonance (MR) procedures and MR test procedures for implants/devices are examined.Since 2012, many interactions of items with MR procedures have been physically described and translated into standardized ASTM and ISO testing procedures. Despite the standardized procedures, the determination of the test method to use is an important decision. The MR user is also responsible for the transfer and interpretation of the individual technical parameters despite the MR Conditional labelling and therefore relatively unambiguous instruction. This includes the total MR examination duration, which often has no clinical practical duration, but is derived from the 15 min of the ASTM radiofrequency (RF) heating test.There has been an increasing standardization of the test methods as well as the MR labeling requirements and the advantageous transfer of the parameters to suitable input masks on the MR systems.The current use of standardized MR test methods and MR marking represents the best possible state of the art from the point of view of the approval of medical devices as well as from a liability point of view for the manufacturers of implants-and for MR users in clinical practice. However, off-label decisions (i.e., deviations from the manufacturer's official MR marking) in everyday clinical practice can be medically justified.

Examining patients with cardiac pacemakers and implantable cardioverter-defibrillator systems (ICD) requires special cautions und preparations in order to assure patient safety.Is it possible for pacemaker and ICD patients to safely undergo MRI examination?This review provides information on interaction between the pacemaker and MRI systems, provides a review on the evidence published so far and describes how to perform a safe MRI examination in a patient with an implanted pacemaker device.MRI in patients with cardiac pacemaker and ICD systems is safe under specified conditions and should be offered to patients with a given indication for a MRI.

Legitimately categorizing software in the healthcare sector is complex. According to European medical devices law, software can be considered a medical device. The decisive factor is whether the software is used for directly controlling a therapeutic or diagnostic medical device or as stand-alone software that achieves specific medical purposes, as they are described in the legal definition of a medical device. A contribution of the software to diagnosis or therapy can be sufficient for the categorization; it does not have to provide the complete diagnosis or the complete therapy itself.This principle will continue to be the same with the new Regulation on Medical Devices (EU) 2017/745, even though the classification rules have been more closely and more specifically tailored to software and more stringent requirements for essential safety and performance requirements have to be met.

Hospital facilities issue numerous risk announcements on corrosion, deformation or premature wearout of medical devices every year. As there is yet little data on the impact of reprocessing on the quality and durability of microsurgical instruments, this paper aims at evaluating the effects of the reprocessing on microsurgical instruments.Jedes Jahr werden in Krankenhäusern Risikomeldungen zu Verunreinigungen, Korrosion, Deformation oder vorzeitigem Verschleiß von Medizinprodukten gemacht. Zu den Auswirkungen des Aufbereitungsprozesses auf die Qualität und Haltbarkeit empfindlicher und sehr feiner Instrumente gibt es bisher sehr wenige Daten. Diese Arbeit untersucht, ob und gegebenenfalls in welchem Umfang mikrochirurgische Instrumente durch den Aufbereitungsprozess geschädigt werden.

Numerous laws, guidelines and recommendations govern the handling and reprocessing of semi-critical medical devices in the field of ENT. Although mechanically reprocessing is characterized as a preferential, manual reprocessing is still conducted in most ENT clinics and medical practices for reasons of cost and practicability. In the presented study, we developed an optimized hygienic concept for reprocessing of medical products in the field of ENT.A demand analysis of rigid endoscopes and of ENT equipment was carried out based on hypothesis that only mechanical reprocessing was performed for the entire instrumentation. Additionally, patient-free activities like preparing instrumentation for examination were investigated. As a result, we could demonstrate that such patient-free activities represent a considerable time factor and as a consequence a cost factor in daily patient care. Necessary investments for only mechanical reprocessing of instrumentation including rigid endoscopes are considerably high, since number of endoscopes have to be kept very high.Zahlreiche Gesetze, Vorgaben, Richtlinien und Empfehlungen regeln und beeinflussen den Umgang und die Aufbereitung semikritischer Medizinprodukte in der HNO. Obwohl als vorrangig zu verwenden charakterisiert, wird nach wie vor in den meisten HNO-Kliniken und Praxen aus Kosten- und Praktikabilitätsgründen die manuelle der maschinellen Aufbereitung vorgezogen. In der vorliegenden Studie wurde ein optimiertes Hygienekonzept erstellt. Es fand eine Bedarfsanalyse starrer Endoskope und des HNO-Instrumentariums bei ausschließlich maschineller Aufbereitung statt. Erstmals wurden zudem patientenferne Tätigkeiten im Rahmen der Patientenuntersuchung zeitlich untersucht. Im Ergebnis zeigt sich, dass patientenferne Tätigkeiten im Umgang mit dem HNO-Instrumentarium einen erheblichen Zeit- und damit auch Kostenfaktor in der Patientenversorgung darstellen. Die nötigen Investitionen für eine rein maschinelle Aufbereitung des Instrumentariums und ins Besondere starrer Endoskope sind erheblich, da die Durchlaufzeit und damit die Anzahl an vorzuhaltenden Endoskopen sehr hoch ist.

The diagnostic validity of a full-thickness resection is higher compared to endoscopic mucosal resection (EMR) or endoscopic mucosal dissection (ESD). Whereas transanal endoscopic microsurgery techniques (TEM, TAMIS) are established therapeutic procedures in the rectum no established and safe minimally invasive or endoscopic procedure exists in the colon.In this study the novel endoscopic full thickness resection device (FTRD, Ovesco, Germany) was investigated concerning success rates with histologically proven full thickness resections, R0 status as well as patient and device safety for the rectum and colon.In the period from November 2014 to June 2015 full thickness resections in the rectum and colon were performed with the FTRD in 20 patients. Data on technical success, R0 resection rate and histologically confirmed full thickness resections were retrospectively analyzed.The following indications were treated in the rectum (n = 11) and colon (n = 9): T1 carcinoma (n = 6) and neuroendocrine tumors (n = 2), untreated and nonlifting adenomas (n = 3) and incomplete resection of adenomas with low and high grade dysplasia (n = 9). The technical success rate was 75 %, 3 technical failures made a conventional polypectomy necessary in 2 patients and in 1 patient an operative resection of the duplicated intestinal wall had to be performed. The median endoscopic follow-up time was 61.5 days (n = 10) and in 7 patients the clip had dislodged at the first follow-up. A thermal perforation in one case of conventional polypectomy gave rise to indications for a partial resection of the colon. In one patient the lesion in the cecum could be reached but not treated for technical reasons. The histological R0 rate was 80 %, whereas the full thickness resection rate was 60 % (85.7 % in the colon and 54.6 % in the rectum). In two patients with carcinoma and incomplete FTRD, surgical treatment was performed. The median size of the resection specimen was 5 cm(2) (range 1.6-12.9 cm(2)).The results show that FTRD is a safe and effective instrument for use in the lower gastrointestinal tract. Limitations of the FTRD system concerning full thickness resection are scarring, fibrosis and thickness of the intestinal wall, especially in the lower rectum; therefore, it is suggested that a simulation with a tube similar in size to the FTRD should be performed during the screening colonoscopy in order to establish whether an endoscopic resection with FTRD is possible.

Flat detectors (FD) have completely replaced image intensifiers in angiography. Due to this development not only the image quality of 2D digital subtraction angiography series (2-D-DSA) could be improved but also the acquisition of computed tomography (CT)-like cross-sectional images (FD-CT) within the angio suite became feasible. These techniques are now being used in daily clinical routine. Only little information about effective doses of these applications to patients has been published in the literature. We describe the effective patient dose of current applications in the field of angiography and demonstrate strategies to minimize the dose to the patient. In addition, we compare FD-CT applications to standard multislice CT applications.

Implantable cardioverter-defibrillator (ICD) leads have to fulfill particular requirements: safe pacing and sensing, detection, and termination of ventricular tachyarrhythmias, if necessary by (multiple) high-energy shocks. At the same time, their implantation has to be simple, they need to provide excellent long-term stability and they must be completely and safely extractable. Numerous technical developments have enabled currently available ICD leads to fulfill these expectations to a high extent. However, some changes of lead design, materials, and manufacturing processes have led to increased lead failure, especially in two lead models (Medtronic Sprint Fidelis®, St. Jude Medical Riata®). The high rate of lead failure was identified only several years after market release, in part because there are no appropriate registries of ICD leads. This review presents background and developments of ICD lead technology and their association with the clinical usage of ICD therapy. To also benefit patients with only slightly-to-moderately increased risk of ventricular tachyarrhythmia, optimum ICD therapy requires optimal leads and sufficiently experienced implanters.

The use and organisation of medical technology has an important role to play for patient and user safety in anaesthesia.Specification of the recommendations of the German Coalition for Patient Safety (APS) for users and operators of anaesthesia equipment, explore opportunities and challenges for the safe use and organisation of anaesthesia devices.We conducted a literature search in Medline/PubMed for studies dealing with the APS recommendations for the prevention of medical device-related risks in the context of anaesthesia. In addition, we performed an internet search for reports and recommendations focusing on the use and organisation of medical devices in anaesthesia. Identified studies were grouped and assigned to the recommendations. The division into users and operators was maintained.Instruction and training in anaesthesia machines is sometimes of minor importance. Failure to perform functional testing seems to be a common cause of critical incidents in anaesthesia. There is a potential for reporting to the federal authority. Starting points for the safe operation of anaesthetic devices can be identified, in particular, at the interface of staff, organisation, and (anaesthesia) technology.The APS recommendations provide valuable information on promoting the safe use of medical devices and organisation in anaesthesia. The focus will be on risks relating to the application as well as on principles and materials for the safe operation of anaesthesia equipment.

An integral part of the conformity assessment process for medical devices is a clinical evaluation based on clinical data. Particularly in the case of implantable devices and products of risk class III clinical trials must be performed. Since March 2010 applications for the authorization of clinical trials as well as for the waiver of the authorization requirement must be submitted centrally in Germany to the appropriate federal authority, the Federal Institute for Drugs and Medical Devices (BfArM) or the Paul Ehrlich Institute (PEI). In addition to authorization, approval by the responsible ethics committee is also required under law in order to begin clinical testing of medical devices in Germany. In this paper, the legal framework for the clinical testing of medical devices as well as those involved and possible procedures including evaluation criteria for the initial application of a trial and subsequent amendments are presented in detail. In addition, the reporting requirements for serious adverse events (SAEs) are explained and possible consequences of the evaluation are presented. Finally, a summary of application and registration numbers for all areas of extensive experience of the BfArM as well as requests and guidance for applicants are presented.

For medical devices with a higher risk, Notified Bodies assess whether the manufacturers and their products fulfill the requirements laid down in the European directives on medical devices. Notified Bodies are designated through a designation procedure by the designating authority, in Germany by ZLG. The requirements for the designation arise from the respective annexes of the directives on medical devices. Since these are only minimal criteria, different documents have been compiled on a European and national level to concretize these minimal criteria regarding the organization, quality management system, resources, and certification procedure. The rules of the ZLG are thereby the essential documents for designation in Germany. Moreover, according to Implementing Regulation (EU) no. 912/2013, the European commission and the other European designating authorities also have to be involved in the designation process. The aim of continuous monitoring of the Notified Bodies with assessments on the bodies' premises as well as with observed audits is to ensure the permanent fulfillment of the requirements. If nonconformities are found in a body's quality management system or in its implementation of the conformity assessment procedures, the body is obliged to provide ZLG with a corrective actions plan. In the case that the nonconformities are not resolved in time or critical nonconformities are found, ZLG may take actions, e.g., restrict the scope of designation, suspend, or - as last resort - withdraw the designation.

Medical devices are of great importance for the prevention, diagnosis and treatment of many diseases. With their broad range and interdisciplinarity, they represent both a very dynamic field of innovation and a significant sector of the economy. The European and thus the German Medical Devices Act aim in this context to make new medical devices for patients and users rapidly available while ensuring safety and performance at the same time. The main responsibility for this lies with the manufacturer. In addition, others are involved in a complex collaboration in the conformity assessment and also later in the marketing phase for the early identification, assessment and minimization of potential risks. This paper presents the legal framework for medical devices and the related roles and responsibilities of various stakeholders, especially the two federal agencies the German Federal Institute for Drugs and Medical Devices (BfArM) and the Paul Ehrlich Institute (PEI). From the perspective of the BfArM the procedure and criteria for risk assessment of incident reports are explained and the experiences and wishes from regulatory practice are described. The active engagement of the BfArM to contribute knowledge from the incident report assessment within the relevant standards organisations and the medical profession is described using examples of medical devices from the field of out-of-hospital ventilation. The paper concludes with a look at future challenges, e.g. in combination products, IT networks and automatization, as well as on current developments to improve risk identification and assessment in a European context.

There has previously been no structured long-term documentation of the results of hip and knee prosthesis operations in Germany. This article presents the objectives, structure and data flow of the newly established German arthroplasty registry (EPRD). The EPRD is run as a subdivision of the German Society for Orthopedics and Orthopedic Surgery (Deutsche Gesellschaft für Orthopädie und orthopädische Chirurgie, DGOOC). It is dedicated to scientific principles and guarantees independency and immediate feedback to surgeons. The cooperation between insurance funds, hospitals, industry and scientific society is the key to success. Additional data acquisition and bureaucratic formalities are limited to a minimum and in particular there is no use of paper. Involving the health insurance funds provides access to relevant routine data. The implant documentation is facilitated by means of an implant library and barcode scanning in the operating room. The EPRD documents the survival of implants including the reasons for revision. Although the highest level of patient data protection is guaranteed, individual patients can be identified in case of implant recalls.

The reprocessing of medical devices for low pathogen or sterile use is in itself potentially risky even though the aim of reprocessing is the avoidance of hygienic or technically functional risks. The methodological principles of risk management for medical devices are described in the standard DIN EN ISO 14971. The recommendations of the Commission for Hospital Hygiene and Infectious Disease Prevention (Kommission für Krankenhaushygiene und Infektionsprävention KRINKO) of the Robert Koch Institute (RKI) and the Federal Institute for Drugs and Medical Devices (Bundesinstituts für Arzneimittel und Medizinprodukte BfArM) "hygiene requirements for the reprocessing of medical devices" clarify numerous reprocessing-specific risks and are structured with reference to the different steps of reprocessing. The aim was a practical combination of the normative risk management methodology with the process-oriented KRINKO/BfArM recommendations, which has provided an interdisciplinary group of experts moderated by the Association of German Engineers (VDI). The main contents of the VDI 5700 guidelines on "hazards associated with the reprocessing--risk management in the reprocessing of medical devices--measures for risk control" and the process of the development of these guidelines is described.

In Otorhinolaryngology, rigid endoscopes are used daily at a high frequency. There is no consensus for reprocessing these medical instruments. Often immersion disinfection procedures are used. The present study examined the possible risk of recontamination by this disinfection method and investigated the possibility of avoiding this risk by using a new immersion quiver system.Using coloured markers, a possible contact of the endoscope with the top edges of quivers of different diameters during endoscope removal was tested for. In addition, it was evaluated whether Staphylococcus aureus transfer is possible via this route. The same methodology was applied to a new immersion quiver system.Whenever removing the rigid endoscopes from the conventional quiver, these touched the top of the quiver, regardless of its diameter. A transfer of Staphylococcus aureus from the quiver to the endoscope via this route could be detected in five out of eight attempts. During endoscope removal from the new immersion quiver system, no contact of the endoscope with the outer quiver occurred in 20 passes. In none of eight trials was a transfer of Staphylococcus aureus from previously contaminated immersion quivers to the endoscope shown; all immersion quivers were sterile after disinfection.After conventional immersion disinfection, recontamination of rigid endoscopes by a contaminated quiver edge is possible. An immersion quiver system can resolve this risk of recontamination easily, by decontaminating not only the endoscope, but also the immersion quiver (inner quiver) itself in the disinfectant solution.

Test standards are developed worldwide by extremely committed expert groups working mostly in an honorary capacity and have substantially contributed to the currently achieved safety standards in reconstructive orthopedics. Independent of the distribution and quality of a test specification, the specialist knowledge of the user cannot replace a well founded risk analysis and if used unthinkingly can lead to a false estimation of safety.The limits of standardization are reached where new indications or highly innovative products are concerned. In this case the manufacturer must undertake the time and cost-intensive route of a self-developed testing procedure which in the ideal case leads to a further testing standard.Test standards make a substantial contribution to implant safety but cannot replace the expert knowledge of the user. Tests as an end to themselves take the actual objectives of standardization to absurdity.

It is 40 years ago that a very popular X-ray device disappeared in German shoe shops: the shoe-fitting fluoroscope or Pedoskop. Since the 1930s, these X-ray machines were an integral part of any good shoe business. Following the entry into force X-Ray Regulation (RöV 1973) the use of these devices was prohibited in Germany.

The effectiveness of the risk management systems established by medical device manufacturers and health-care facilities is clearly mitigated by European and national legal provisions. Laws, regulations and authorities prevent the systematic exchange of much safety-relevant information. The obligation to report adverse events is suspended for many relevant risks associated with medical device use. Reporting into the vigilance system is of little avail for users. Reporting even may endanger the information provider. The federal fragmentation of the German vigilance system poses a risk for patients. Risk management in health-care facilities without risk policy is dangerously incomplete.

This review presents the potential indications for different airway devices in the intensive care unit (ICU). Since the interface during noninvasive ventilation is located outside the body, sedation is not regularly needed. Therefore, selection of a fitting mask is essential to avoid mask intolerance which is one of the biggest problems during noninvasive ventilation. Full-face masks are the interfaces mostly used for noninvasive ventilation to treat acute respiratory failure; here, mouth breathing is possible which is often necessary during acute respiratory failure. Good alternatives are total face masks and the helmet, whereas nasal masks and mouthpieces are not regularly used on the ICU. Extraglottic airway devices and coniotomy are used for the management of difficult airway situations on the ICU. Endotracheal intubation remains the gold standard procedure for airway management. However, this procedure is associated with a number of complications. Tracheostomy is the airway access of choice when long-term mechanical ventilation is necessary.

Every year in Germany approximately 3,500 patients receive a cochlear implant or other hearing implants with an implantable magnet. At the same time more and more patients are examined by magnetic resonance imaging (MRI). For the indications and execution of this imaging modality a number of restrictions and safety measures have to be considered.This article is based on the restrictions of the manufacturers and a selective literature search in PubMed using the following keywords: MRI compatibility/MRI safety + cochlea implant/auditory brainstem implant/Bonebridge/Carina/Esteem/Otomag/Sophono alpha/Vibrand Soundbridge. We included all 20 publications of this search concerning the MRI compatibility of the hearing implants complemented by papers cited in the primary articles.High electromagnetic field intensities as used in MRI can cause malfunction and dislocation of the implant or the magnet in the device. Older cochlear implants (CI) and the current CIs produced by Advanced bionics without explantation of the magnet, some CI models produced by the company Cochlear and the middle ear implants Carina®/Esteem® (older models) and Vibrant-Soundbridge® are not approved for MRI examinations. Other hearing prostheses are approved for 0.2 T, 1.0 T or 1.5 T MRI and in exceptional circumstances 3 T MRI. Recommendations of the manufacturers have to be followed, notably wearing a head bandage during the imaging procedure. The longitudinal axis of the patient's head has to be to positioned parallel to the main magnetic field of the scanner. The patient may not move the head laterally during the examination. Possible artefacts and the reduced validity of the results of skull MRI have to be considered when evaluating the indications for the examination.For patients wearing hearing implants with an implantable magnet the indications for MRI in devices with MRI certification should be rigorously restricted. Possible defects/dislocation of the implants may occur and the quality of the skull MRI images is reduced. A close contact between the radiologist and the implanting team is required. Other diagnostic procedure options should be exhausted before employing MRI.

It has become common for hospitals to borrow medical devices from manufacturers to test and try them during the daily routine before purchasing which today is known as trial provision. This study aims at offering a precise definition of trial provisions and a description of the way of proceeding.A total of 60 medical practitioners in 5 German hospitals were surveyed (surgeons n = 40, 66.7 %, radiologists n = 12, 20 % and anesthesiologists n = 8, 13.3 %). Manufacturers and distributors of medical devices (n = 10) and hospital administration executives (n = 8) were also interviewed.Trial provisions are a promotional marketing tool for manufacturers of medical devices. By lending the device over a specific period for testing before purchasing, hospitals can gain experience in the usage and handling of devices on which a purchase decision can be made. The survey revealed that there are basically three procedural methods which can, however, differ even within one hospital.Trial provisions influence purchasing decisions in clinics. If implemented incorrectly trial provisions may compromise physical integrity, safety and health of patients and can thus lead to judicial and legal consequences for hospitals and medical staff.

The number of injuries caused by accidents while springing on a trampoline has increased significantly. This study therefore focused on the incidence, morbidity and circumstances of the accidents in pediatric patients.The children admitted to this hospital from 2002 to 2010 were re-examined and the children injured during trampolining were asked to fill out a questionnaire focusing on the mechanism of the injury and the circumstances.A total of 268 accidents were included in the study and 28% of the injuries were severe (e.g. fracture, luxation and rupture). If there were special safety measures (e.g. safety net, floor mats, surrounding water 63%) 28.4% of the injuries were severe and without safety measures 28.6% were severe. Safety measures did not influence the incidence of severe trauma (p=1). If a trampoline was equipped with a safety net (53%) 31% of the injuries were severe and without a safety net 25% were severe (p=0.473).Pediatric accidents on a trampoline result in severe injuries in 28% of cases. There is no difference in the severity of the injury regarding trampolines with or without special safety measures. Safety nets do not reduce the risk of severe injury.

Development of magnetic resonance imaging (MRI) device technology continues to increase the static magnetic flux densities applied and consequently leads to considerably increased occupational exposure. This has already made it necessary to review limits of occupational exposure and to postpone European legal regulations for occupational exposure to electromagnetic fields. This raises the question whether and if so which adverse health effects and health risks might be associated with occupational exposure to MRI ultra-high static magnetic fields. Based on a survey on interaction mechanisms recommendations and safety rules are presented to help minimize adverse health effects of emerging ultra-high field MRI.

Medicines and medical devices do not only differ in the approval process, but also in the aim and conduct of clinical trials. We first discuss important differences between medicinal products and medical devices. Emphasis is put on the differences in the framework for clinical trials. We point out that a different analysis set should be used in clinical trials of medical devices when compared with medicinal products and medical devices in the USA. Specifically, regulators generally ask for the full analysis set based on the intention-to-treat principle as proof of efficacy of medicines. A central aspect of clinical trials of medical devices is that they have to be tested under normal conditions of use according to the performance data. As a result, all data acquired while the medical device was not during normal conditions of use should be excluded from statistical analyses. We discuss statistical methodological particularities of medical devices, such as blinding and the control of placebo effects. Using the conservative treatment of anal incontinence as an example, we show that comprehensive technical and physical knowledge is required for assessing the utility of medical devices. Finally, we consider reporting of severe adverse events and of severe adverse device effects of medical devices.

Rules and regulations form the framework of Health Technology Assessments. Legal issues are directly associated with the technology (as patents/licenses) or to the patients and their basic rights (as autonomy). In order to identify the regulations of interest as well as the relevant publications in a systematic and transparent way a specific methodological approach is required. In the absence of adapted methods, our objective was to develop a methodological approach to the systematic retrieval of information on legal issues.No publications on adapted methods could be identified. We therefore developed a procedure following the workflow of information retrieval for effectiveness assessments. This workflow consists of 8 steps: 0. pre-search: identification of the relevant rules, regulations and patient-related issues, 1. translation of the search question, 2. concept building, 3. identification of synonyms, 4. selection of relevant information sources, 5. design of the search strategies, 6. execution and quality check, 7. saving the results and reporting.There are numerous publications on legal issues associated with health technologies. Specifically adapted procedures are qualified to identify them in a systematic and transparent manner using the appropriate sensitivity and precision. A wider application seems to be reasonable in order to further test its practicality against more topics and to modify the proposed method if indicated.

The main problem with the treatment of arterial stenoses by percutaneous transluminal angioplasty (PTA) or stent implantation is the relatively high restenosis rate. The objective of this prospective single-center study was to evaluate a mechanical rotational catheter (Straub Rotarex®) for its safety and efficacy in the treatment of in-stent reocclusions.78 patients with a mean age of 64.2 ± 8.3 years (42 - 85) were treated by means of the Rotarex® catheter. All patients had in-stent reocclusions of the femoropopliteal arteries. The preinterventional Rutherford stage was on average 3.36 (2 - 5). The mean lesion length was 14.7 cm (6 - 30 cm). The ankle-brachial index (ABI) was determined prior to and after the intervention, as well as after 12 months. An additional follow-up was performed using color-coded duplex sonography.The technical success rate was 97.4 % (76 / 78). In 52 / 76 patients (68.4 %), adjunctive balloon dilation was performed, and 8 / 76 (10.5 %) patients required a stent implantation. Clinically, there was an increase in the ankle-brachial index from 0.61 ± 0.17 to 0.85 ± 0.15 post-interventionally. After 12 months, it was 0.78 ± 0.16, and the average Rutherford stage fell to 1.65 (1 - 3). During the follow-up observation period, there were 14 (18.4 %) restenoses. Two dissections after Rotarex were recorded as peri-interventional complications. No distal embolizations were observed. There were no amputations or deaths during the entire period of the study.The recanalization of in-stent reocclusions of femoropopliteal arteries using the Rotarex® system is safe and effective. The low rate of restenosis at 12 months appears to be promising.

Medical devices must be safe and functioning states the law. Treatments with medical devices need not be efficacious to be allowed. We investigated special requirements and problems arising from the law.The market for medical devices is contrasted with that for drugs. The requirements of relevant laws are discussed. Finally, published clinical studies on anal incontinence are analysed with respect to their methodological quality.Clinical trials of medical devices for treat-ing anal incontinence are of poor methodological quality thus preventing evaluation of the devices' utility.Large, high quality clinical studies of the efficacy of medical devices for treating anal incontinence are urgently needed. Only such studies enable health technology assessment and comprehensible decisions on reimbursement by health insurance.

The medical device industry, strongly dominated by medium-sized firms, has significant growth potential and a high number of job opportunities with 170,000 employees in more than 11,000 companies. Approximately one third of the business volume is achieved with innovative products that are less than three years old. The safety, quality and efficiency of the products is tested and approved by CE certification. Due to the heterogeneous field of devices, however, evidence requirements must be differentiated according to the type of device in question. Transparency is as important as the type of evidence, and industry is well aware of the significance of transparency for credibility in the market. Industry believes that all the stakeholders affected must collaborate to define the evidence requirements and decide which data are necessary to assess the benefits of a technology. Before a consistent level of transparency can be achieved, however, it is crucial to jointly develop a framework of requirements including invasiveness, risk potential, patient-relevant endpoints and intended use of the technology, as well as the data source. Transparency is a process that can only be achieved if all stakeholders cooperate successfully. Also, it is important to keep in mind that the development of study designs and reliable evidence needs time. In the interest of all patients it is essential to maintain an innovation-friendly climate in Germany.

Single-port access surgery (SPA), the most recent development in laparoscopic surgery allows operations to be carried out through only a single incision using special multichannel ports. By the use of a smaller access tissue trauma and access-related complications, such as wound infections, adhesions and incisional hernias can be decreased considerably. Because of less postoperative pain earlier mobilization of patients can also be achieved. By placing the access transumbilically, e.g. in SPA cholecystectomy (SPA-CHE), the scar is perfectly covered achieving an optimal cosmetic result. Meanwhile various so-called single ports and camera systems have been developed. Great importance is attached to the development of special (double) bended and/or articulating instruments because with these instrument triangulation is possible through only one incision. Nevertheless the stereoscopic situation in SPA-CHE implicates some factors related to retraction, exposition and release of the gallbladder but some difficult situations can be managed safely with some tips and tricks.Because of the already worldwide spread of SPA-CHE this technique will soon become an established minimally invasive technique. However, appropriate studies confirming the clear advantages of the technique are still lacking.

Medical devices cover a wide spectrum of products with very different diagnostic and therapeutic applications. However, for market licensing, uniform rules apply. Uniform rules are also valid for coverage decisions in German health care. In this article, the criteria for the assessment of benefit and efficiency of innovative biomedical technologies are described from the perspective of the statutory health insurance system. The key concepts relevant in the mandatory health insurance' "innovation"' "benefit", and "economic efficiency" are characterized. Only measurable effects of an intervention which lead to a more than marginal improvement in prognosis, symptoms, or quality of life as compared to a standard treatment are considered as beneficial. An innovative device is, therefore, subject to a benefit assessment if it is not yet reimbursed (or not yet part of the benefit package), when it is relevant to the health care system and a high public interest exists. In addition, it is important to consider a positive benefit assessment as a part of the value added chain to avoid conflicts of interest. Within the scope of early technology assessment, some conclusions can already be drawn in the early developmental stage of a device.

According to the German medical devices act and German ordinance on operators of medical devices, human eye tonometers have to be retested every two years. Independent verification laboratories carry out the metrological controls for tonometers which are used by ophthalmogists. Applanation tonometers are frequently used for the accurate measurement of intraocular pressure. For metrological controls these measurement devices are retested by means of test devices (transfer standards) used by verification offices and by private test agencies. PROCEDURE AND METHOD: 25 test devices for applanation tonometers (15 cross-beam balances and 10 force transducer devices), applied for metrological controls by verification offices and by private test agencies, were checked by means of comparative measurements with regard to their quality of measurement and their handling. An applanation tonometer of the type AT 870 (manufacturer: Haag-Streit, Switzerland) served as reference device. Within a measurement range from 9.81 mN to 78.45 mN, upward and downward measurements were performed for the mechanical force of applanation tonometers and for the determination of the reverse span.The investigations for all test devices of applanation tonometers show the compliance within permissible error limits in the observed measuring range for the reverse span with the tonometer AT 870. Some instruments exceed the permissible error limits for test devices for up- and downward force measurements. A comparison concerning the measuring accuracy of two different types of test devices (cross-beam balance and force transducer device) shows that the force transducers tend to have smaller measurement uncertainties.The high metrological demands on test devices for applanation tonometers for the measurement of mechanical force, a prerequisite for accurate calibration and adjustment of this tonometer type, require much experience and special training of the operator handling these standards, in order to minimize subjective error sources. Schoolings with practical trainings for user are recommended to minimize these errors. At least every three years the test devices have to be maintained and recalibrated, in order to guarantee proper function and accuracy of the measurement.

In some cases of severe acute respiratory distress syndrome, hypoxemia occurs despite optimized conservative therapy; however, extracorporeal membrane oxygenation (ECMO) can assure sufficient gas exchange. To increase safety and reliability of devices, the oxygenator design was optimized integrating new plasma-resistant composite membranes and new blood pumps are used with longer durability and reduced blood cell damage. Another approach is the use of an arterio-venous pumpless extracorporeal lung assist (pECLA) using an oxygenator with reduced pressure drop to simplify management and to avoid pump-related complications. First attempts were made to integrate basic control and safety concepts in ECMO circuits, but this does not seem to be sufficient to overcome the specific problems of ECMO (long-term use and limited supervision of the intensive care unit). The integration of sophisticated automated control and safety concepts in combination with revised ECMO circuits could allow a more reliable application of ECMO of the intensive care unit without continuous observation by a perfusionist. Easier intra- and interhospital transfer of patients with running ECMO would be another advantage.