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Biomedical subjects

F Bootz

Publications and source records attributed to F Bootz.

At least 19 recordsLinked to original sources
PubMed2007

[Manipulator assisted endoscope guidance in functional endoscopic sinus surgery: proof of concept].

BACKGROUND: Functional endoscopic sinus surgery (FESS) is characterized by single-handed preparation and guidance of the endoscope by the nondominant hand. This results in an additional extension of operation time by up to 15% and ergonomic deficits. The aim of this study is the conception of an automated assistance system for FESS in view of the following questions: (1) Which degree of surgical automation is suitable for FESS? (2) Which design is suitable? (3) What are the properties of the technical system (planning, time, accuracy, precision) of the selected system? (4) Does the system offer potential for a clinical application? METHODS: In all 49 FESS were analyzed for surgical workflows. Measurement of the maximum forces within FESS was performed with 40 trials on an anatomical model. Three different mechanical systems were used in ten FESS and evaluated using the ICCAS Human-Machine Evaluation Scale. For realization of automated endoscope guidance an engine-driven and -braked manipulator (PA10-6c, Mitsubishi, Japan) was used. The technical parameters determined were expenditure of time for the preoperative planning of workspace, surgical accuracy and precision of the intraoperative endoscope positioning, maximal forces, and time. RESULTS: Concept-conditioned instrument changes amount to an average of 41.1 and 18.9% (5.21 min) time requirement for each FESS side. Maximum forces on the mucous membrane during a conventional FESS were measured at 9.8 N (5.9-9.8). Usability of the mechanical endoscope holder was estimated in 18 of 20 cases to be inferior to the standard procedure. The time needed for segmenting the intranasal workspace was 15.2 min (10.0-23.0). The maximum deviation of the automatically driven endoscope from a planned position amounted to 0.85 mm (manually 4.64 mm). The maximum force was measured with 1.1 N in the z direction (manually 9.8 N). Automated guidance of the endoscope to an intranasal position needed 7.25 s (6.4-7.9); manually 12.64 s (5.9-43.0). CONCLUSION: Guidance of the endoscope for FESS by an automated motor-driven system is possible. The conception which is based on workflow analysis favors a system with automatic definition of the workspace and a manual movement of the endoscope. The examined system offers a potential for clinical application. Definition of the automation level and development of a man-machine interface is more important than selection or reconstruction of a special manipulator for endoscope guidance in FESS from a surgical point of view.

Endoscopes↗
PubMed2006

[Workflow analysis to assess the efficiency of intraoperative technology using the example of functional endoscopic sinus surgery].

Evaluation of the efficiency of surgical technology systems has to date been largely subjective. The aim of this study was to develop an ontology for surgical procedures usable workflow structures, and the evaluation of surgical workflow analysis using the example of functional endoscopic sinus surgery (FESS). A total of 38 procedures (20 patients) were included. Surgery was carried out by seven different surgeons with different degrees of training. Description of the surgical procedures and resources is based on the standard EN1828/2001 (Structure for Classification and Coding Systems for Surgical Procedures). In addition the requirements of the Workflow Reference Models (document no. Tc00-1003), Workflow Management Coalition (WfMC) were integrated. The workflow recorded the position, frequency of change of position, use time, cleaning time and concept based instrument changes. A total of 293 items were used to define FESS. A total of 1,029 different endoscopic positions were documented. These could be combined into five major endoscopic positions. The frequency of position changes was 27.1 per side, the period spent in an endoscopic position is about 1.31 min. Time for the concept-caused instrument changing was 6.44 min per side. This study demonstrates the need for assistance in guiding the endoscope in FESS. Using the workflow-data, the concept of an assistant system is possible. We offer a basis for discussion of the development of an ontology, recording and analysing surgical workflows and their practical application.

Biotechnology↗
PubMed2005

[Slide-based multi-parametric cytometry in ENT. Perspectives for the clinic and research].

BACKGROUND: Flow cytometry is the standard method for the multi-parametric analysis of cells. However, for about a decade, an instrument has been available which analyses fluorescing cells immobilised on slides called a laser scanning cytometer (LSC). Its design, according to the principles of slide-based cytometry, promises many advantages, especially in the analysis of minimal sample volumes. METHODS AND PATIENTS: To date, applications for cultured cells and animal models have been established. Its use for clinical purposes, however, remains to be critically evaluated. We analysed a variety of specimens obtained in our clinical routine. RESULTS: First, the instrument's resolution was evaluated using standardised particles. This showed a very good sensitivity across a wide range of fluorescence intensities at various wavelengths. Next, diverse applications for tissue engineering, immunophenotyping, and ENT-oncology were tested. Considering its microanalytical capacities, LSC proved to be a convincing tool for clinical use. Additionally, complex structures such as bi-layers of cultured cells were analysed. CONCLUSION: A broad spectrum of applications in clinical practice and research for the LSC is evident.

Equipment Design↗
PubMed2005

[Pedicled and free flaps for reconstruction in the head-neck region].

For reconstruction in the head-neck region, either pedicled or free flaps can be used depending on the site of origin and the place of reconstruction. Pedicled flaps have definite limitations, therefore, free transplants are becoming continuously more popular. Today, microvascular reanastomosed transplants are those most commonly used in reconstructive head-neck surgery. In this contribution, we present and explain the most important types of flaps and their indications.

Cervicoplasty↗
PubMed2005

[Mechatronic in functional endoscopic sinus surgery. First experiences with the daVinci Telemanipulatory System].

BACKGROUND: This study examines the advantages and disadvantages of a commercial telemanipulator system (daVinci, Intuitive Surgical, USA) with computer-guided instruments in functional endoscopic sinus surgery (FESS). METHODS: We performed five different surgical FESS steps on 14 anatomical preparation and compared them with conventional FESS. A total of 140 procedures were examined taking into account the following parameters: degrees of freedom (DOF), duration , learning curve, force feedback, human-machine-interface. RESULTS: Telemanipulatory instruments have more DOF available then conventional instrumentation in FESS. The average time consumed by configuration of the telemanipulator is around 9+/-2 min. Missing force feedback is evaluated mainly as a disadvantage of the telemanipulator. Scaling was evaluated as helpful. The ergonomic concept seems to be better than the conventional solution. DISCUSSION: Computer guided instruments showed better results for the available DOF of the instruments. The human-machine-interface is more adaptable and variable then in conventional instrumentation. Motion scaling and indexing are characteristics of the telemanipulator concept which are helpful for FESS in our study.

Clinical Competence↗
PubMed2005

[Virtual training in head- and neurosurgery].

BACKGROUND: Surgical skill requires training at close-to-reality scenarios. Conventional procedures (practical exercises, anatomical or animal cadavers) are increasingly in conflict with objective parameters (costs of OR, quality management, cadavers availability and cost). Surgical procedures can be covered by using Virtual Surgical Reality (VSR). METHODS: We examined the principle of a VSR system and evaluated the results with 30 probands by the example of modified radical mastoidectomy and ventriculocisternostomy. Probands were divided in experienced (A) and non-experienced surgeons (B). The protocol included time of surgery, collisions and fatal injuries at altogether 15 passages (10 passages - break of 14 days - 5 passages). Additionally the Medical Level of Trust (LOT) describes the confidence into the surgical scenario and thus the quality by volume illustration, texture and haptic data feedback to the user. We used a numeric scale between 0 and 100 and the starting point of 50. RESULTS: The learning effect can be confirmed for both virtual scenarios. The mastoid scenario reaches a total confidence index LOT of 75. The ventricle scenario is evaluated with a total confidence index of 84. The necessary time for the opening of the antrum is reduced from 15.0 minutes (group A) and 22.5 minutes (group B) around 37 % to 9, 5 (group A) and around 56 % to 10.0 minutes (group B). The virtual haptic result was evaluated positive in both scenarios. CONCLUSIONS: VSR systems have the potential to revolutionize surgical training. All surgical experienced probands evaluated the VSR-scenario as near-to-reality. "Suspension of Disbelief" is the major condition for effective virtual reality training systems.

Clinical Competence↗
PubMed2004

[Carcinoma of the mouth and pharynx--better prognosis by an early diagnosis!].

Carcinomas of the mouth and pharynx rank sixth of all malignant tumours worldwide. They are responsible for 10% of the newly diagnosed malignant tumours. The median five year survival rate is 50%, depending on tumour localisation and size, but mainly determined by lymph node metastases. Carcinomas of the mouth and pharynx cause symptoms that resemble those of common harmless diseases of the head and neck such as pharyngitis. This can lead to misinterpretation by both, the patient and the doctor. Since the initial delay by the patient is difficult to influence it is very important that the doctor is aware of a possible malignant disease. Persistent common symptoms such as swallowing impairment or hoarseness, mucosal lesions, such as leukoplakia, a persistent cervical lymph node and unresponsiveness to initial treatment, must prompt the doctor to initialise appropriate diagnostic steps (incisional biopsy, e.g.). Only early diagnosis can help to improve the prognosis of patients with carcinomas of the mouth and pharynx.

Adult↗
PubMed2004

Eosinophilia in nasal polyposis: its objective quantification and clinical relevance.

BACKGROUND: Eosinophilia within nasal polyps is often taken as a criterion for adjuvant medical treatment postoperatively such as topical steroids. OBJECTIVE: This study was performed in order to validate a new technique for objective quantification of eosinophilia by using laser scanning cytometry (LSC), to compare these results with manual scoring and routine histopathology, and to correlate them with the history of allergy or recurrence. METHODS: LSC was used for semi-automated analysis of single-cell preparations from representative ethmoidal polyps obtained during routine paranasal sinus surgery (n=41). This microscope-based instrument scans the cells after immobilization of cells on a glass slide and after triple staining of cytokeratin, eosinophilic granula, and DNA. The location of each cell is stored with the fluorescence data. Therefore, the morphology of every cell can be documented by re-staining with haemotoxylin and eosin and re-localization on the slide. Subsequently, slides were subjected to manual scoring. The remaining polyps were analysed by routine histopathology. RESULTS: Data from LSC and manual scoring showed good correlation (r=0.81, P<0.001), whereas there were discrepancies with histopathology. Eosinophilia scored by LSC and histopathology was neither correlated with the history of allergy nor with recurrence as determined by Fisher's exact test independent of the definition of eosinophilia (> or =2%, > or =3%, or > or =5% of all cells). CONCLUSION: Scoring eosinophilia by LSC in comparison with histopathology does not contribute to a more reliable basis for adjuvant medical therapy in nasal polyposis. Instead, functional parameters (cytokine production, apoptosis) may serve better.

Eosinophilia↗
PubMed2003

[Teleteaching in otorhinolaryngology (part 1). Real-time transmission of a congress in picture and tone into the Internet].

The transmission of scientific seminars into the Internet represents a new application of modern technologies for teleteaching. We digitally recorded 74 seminars and discussions during the 8th annual meeting of the German Society of Skull Base Surgery with five cameras and eight microphones, and transformed the data live with the real-Producer using a video card.This transferred data stream was sent via ISDN (128 kbit/s) to a real-server at the university, which was used for distribution in the net. The seminars could be called up in the display format of 320x240 pixels with a delay of 3 min (minimum: 30 s, as a function of the connection of the user) at each computer with Internet entrance. Altogether,we registered 3,284 accesses to the presentations following the congress until June 2002. The quality of picture transmission (24-36 kbit/s) and the quality of tone (audio stream: 5 kbit/s) were sufficient to understand the contents of the slide, video or computer presentation. The transmission of scientific meetings into the Internet can increase, with a justifiable technical expenditure, their efficiency by the ubiquitous availability of the information and the extension of the audience.

Computer Systems↗
PubMed2003

[Teleteaching in otorhinolaryngology. Part 2: the European database "medicstream"].

Searching the medical literature is mainly characterized by the use of databases. The time for reviewing and printing a paper causes a delay between the first presentation of scientific results in a lecture and the appearance of the appropriate journal publication. Moreover, the possibilities for the integration of multimedia data are limited. Because of the development of new compression algorithms for audiovisual digitization software, the near simultaneous transmission of scientific presentations, both visually and aurally, has been possible since 1999. The section telemedicine of the interdisciplinary study group on image guided surgical navigation from the University of Leipzig has developed "medicstream" as a unique, audiovisual, scientific internetdatabase. It allows the documentation of presentations at congresses and courses, including the discussion,over a freely accessible, widely available homepage, using a home developed streaming technology. All presentations are examined by an authorized editorial committee consisting of representatives with different medical specializations for content before the admission to the data base. A total of 392 presentations from seven scientific meetings can be selected by an integrated search machine and viewed with Windows Media Player or Real Player using a conventional or faster internet connection to the homepage www.medicstream.de. The quality of the audiovisual transmission depends on the receiver-lateral data transmission rate,whereby the minimum variant of 56 kB/s is characterized by good detectability of the contents. In an analysis period of 242 days,we registered 44,199 accesses and 4,488 attendances. The telemedicine data base "medicstream" can optimize quality and extend medical education by live-streaming as well as by archiving scientific presentations as audiovisual data.

Congresses as Topic↗
PubMed2003

[MRI-guided pediatric interventions].

AIM: There are only a few diagnostic or therapeutic procedures where MR imaging is applied during pediatric interventions. This study will describe indications, complications as well as the advantages and disadvantages of MRI-guided interventions based on a case study in an open MRI scanner. MATERIALS AND METHODS: 14 procedures were performed in an open MRI scanner (Signa SP/i, GEMS) on 13 children (1 - 16 yr) with bone, soft tissue and brain lesions (1 - 4 cm diameter). Localization of the pathology, targeting and final control of the result were based on images acquired with SE-, 3D-, GE-sequences pre- and post-contrast as well as FSE-sequences. Interactive MRI-guided instrument navigation was performed using a multiplanar T1w GE-sequence. RESULTS: Eight biopsies (incl. 1 rebiopsy), two tumor resections, one removal of a free joint mouse and three tumor-markings were performed without complications. Five biopsies provided appropriate sample quality for a histological diagnosis while two samples were too fragmented requiring a second biopsy (one of them MRI-guided). Surgical progress during tumor resection and marking could be controlled during the intervention without repositioning the patient. DISCUSSION: MR image guided pediatric interventions combine the advantage of an imaging system without ionizing radiation and the high soft-tissue contrast. The low number of these kinds of procedures can be explained by the relatively high costs for the intervention, the increased duration for each procedure and the limited availability of open MRI systems. The integrated localization-system helps during planning of the access path when facing complex anatomical structures and provides safe navigation in sensitive regions like the epiphyseal cartilage. Recent and expected developments of the required MR-compatible biopsy instruments could provide higher efficiency for appropriate sample size and quality. Summarizing, MRI-guided pediatric interventions have shown to be a promising method at the beginning of its development.

Adolescent↗
PubMed2003

Comparison of the sensitivity of in vivo antibody production tests with in vitro PCR-based methods to detect infectious contamination of biological materials.

Bacteria and viruses may be transmitted to laboratory rodents by contaminated biological materials such as transplantable tumours, cell lines, sera or other biological materials. Biological materials are currently being screened using the mouse or rat antibody production (MAP/RAP) test (serological testing). We decided to test and validate an alternative assay using polymerase chain reaction (PCR/realtime PCR) technology to detect viral contamination directly in biological material. The aim of this study therefore is the validation of our new PCR assays and the comparison of PCR and the MAP test. For 8/14 viruses, conventional PCR was more sensitive and more specific than the MAP test in detecting murine viruses. For 12/14 viruses, the realtime PCR was more sensitive than the MAP test. In 2/14 cases, all three detection methods had the same sensitivity. Furthermore, PCR screening clearly conforms to the principles of the 3Rs as a replacement technique because it eliminates the need for using animals to screen for murine viruses in biological material.

Animals↗
PubMed2002

[Fantoni translaryngeal tracheotomy (TLT) with rigid endoscopic control].

RATIONALE: The incidence of translaryngeal tracheotomy (TLT)-associated peri- and postoperative complications should be assessed prospectively. METHODS: TLT was carried out in operation-theatre under rigid endoscopic control. Peri- and postoperative complications, decanulement and late sequelae were assessed in ENT-patients. In patients of other wards only perioperative complications were evaluated. RESULTS: 41 patients (26 ENT-patients, 15 patients of other wards) were tracheotomised by TLT. Perioperatively, we observed 3 technical problems (accidental pulling through of the tracheostomy tube). In 2 of these cases TLT could be completed without problems, in 1 case TLT was converted to surgical tracheotomy. Postoperatively, we could find no complications in 26 ENT-patients. Decanulation took place after 7 days on average. We found no tracheocutaneous fistulas or tracheostenoses, scars were unobtrusive. CONCLUSIONS: TLT with rigid endoscopy is a simple percutaneous tracheotomy-technique with a low complication rate.

Adult↗