Triplet Rydberg States of Aluminum Monofluoride.

Aluminum monofluoride (AlF) is a suitable molecule for laser cooling and trapping. Such experiments require extensive spectroscopic characterization of the electronic structure. Two of the theoretically predicted higher-lying triplet states of AlF, the counterparts of the well-characterized D1Δ and E1Π states, had not been experimentally identified yet. We here report on the characterization of the d3Π (v = 0-6) and e3Δ (v = 0-2) states, confirming the predicted energetic ordering of these states (J. Chem. Phys. 1988, 88, 5715-5725), as well as of the f3Σ+ (v = 0-2) state. The transition intensity of the d3Π, v = 3 - a3Π, v = 3 band is negligibly small. This band gets its weak, unexpected rotational structure via intensity borrowing from the nearby e3Δ, v = 2 - a3Π, v = 3 band, made possible via spin-orbit and spin-rotation interaction between the d3Π and e3Δ states. This interaction affects the equilibrium rotational constants in both states; their deperturbed values yield equilibrium internuclear distances that are consistent with the observations. We determined the ionization potential of AlF to be 78,492(1) cm-1 by ionization from the d3Π state.

A systematic review and meta-analysis of the clinimetric properties of the core outcome measurement instruments for clinical effectiveness trials of nutritional and metabolic interventions in critical illness (CONCISE).

BACKGROUND: CONCISE is an internationally agreed minimum set of outcomes for use in nutritional and metabolic clinical research in critically ill adults. Clinicians and researchers need to be aware of the clinimetric properties of these instruments and understand any limitations to ensure valid and reliable research. This systematic review and meta-analysis were undertaken to evaluate the clinimetric properties of the measurement instruments identified in CONCISE. METHODS: Four electronic databases were searched from inception to December 2022 (MEDLINE via Ovid, EMBASE via Ovid, CINAHL via Healthcare Databases Advanced Search, CENTRAL via Cochrane). Studies were included if they examined at least one clinimetric property of a CONCISE measurement instrument or recognised variation in adults ≥ 18 years with critical illness or recovering from critical illness in any language. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist for systematic reviews of Patient-Reported Outcome Measures was used. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were used in line with COSMIN guidance. The COSMIN checklist was used to evaluate the risk of bias and the quality of clinimetric properties. Overall certainty of the evidence was rated using a modified Grading of Recommendations, Assessment, Development and Evaluation approach. Narrative synthesis was performed and where possible, meta-analysis was conducted. RESULTS: A total of 4316 studies were screened. Forty-seven were included in the review, reporting data for 12308 participants. The Short Form-36 Questionnaire (Physical Component Score and Physical Functioning), sit-to-stand test, 6-m walk test and Barthel Index had the strongest clinimetric properties and certainty of evidence. The Short Physical Performance Battery, Katz Index and handgrip strength had less favourable results. There was limited data for Lawson Instrumental Activities of Daily Living and the Global Leadership Initiative on Malnutrition criteria. The risk of bias ranged from inadequate to very good. The certainty of the evidence ranged from very low to high. CONCLUSIONS: Variable evidence exists to support the clinimetric properties of the CONCISE measurement instruments. We suggest using this review alongside CONCISE to guide outcome selection for future trials of nutrition and metabolic interventions in critical illness. TRIAL REGISTRATION: PROSPERO (CRD42023438187). Registered 21/06/2023.

Core outcome measures for clinical effectiveness trials of nutritional and metabolic interventions in critical illness: an international modified Delphi consensus study evaluation (CONCISE).

BACKGROUND: Clinical research on nutritional and metabolic interventions in critically ill patients is heterogenous regarding time points, outcomes and measurement instruments used, impeding intervention development and data syntheses, and ultimately worsening clinical outcomes. We aimed to identify and develop a set of core outcome domains and associated measurement instruments to include in all research in critically ill patients. METHODS: An updated systematic review informed a two-stage modified Delphi consensus process (domains followed by instruments). Measurement instruments for domains considered 'essential' were taken through the second stage of the Delphi and a subsequent consensus meeting. RESULTS: In total, 213 participants (41 patients/caregivers, 50 clinical researchers and 122 healthcare professionals) from 24 countries contributed. Consensus was reached on time points (30 and 90 days post-randomisation). Three domains were considered 'essential' at 30 days (survival, physical function and Infection) and five at 90 days (survival, physical function, activities of daily living, nutritional status and muscle/nerve function). Core 'essential' measurement instruments reached consensus for survival and activities of daily living, and 'recommended' measurement instruments for physical function, nutritional status and muscle/nerve function. No consensus was reached for a measurement instrument for Infection. Four further domains met criteria for 'recommended,' but not 'essential,' to measure at 30 days post-randomisation (organ dysfunction, muscle/nerve function, nutritional status and wound healing) and three at 90 days (frailty, body composition and organ dysfunction). CONCLUSION: The CONCISE core outcome set is an internationally agreed minimum set of outcomes for use at 30 and 90 days post-randomisation, in nutritional and metabolic clinical research in critically ill adults.

Prevalence of hypophosphatemia in the ICU - Results of an international one-day point prevalence survey.

BACKGROUND & AIMS: Hypophosphatemia (HypoP) is associated with organ dysfunction and mortality. Despite its potential severe consequences, HypoP remains poorly characterized in terms of real prevalence and timing of onset. The primary objective was to determine the prevalence of HypoP defined as blood phosphate <0.8 and < 0.65 mmol/l on one particular day at international level. METHODS: One-day point prevalence survey conducted by the Section of Metabolism, Endocrinology and Nutrition (MEN) of the European Society of Intensive Care Medicine (ESICM) during week 11-2020. RESULTS: In total, 56 adult and 4 paediatric ICUs, from 22 countries participated: 41 ICUs were mixed medico surgical, the 19 others being cardiac, medical or surgical. Phosphate measurements were performed daily in 21 ICUs, and 1-3 times per week in 39 ICUs. On D-Day 909 patients (883 adults) were present and 668/883 (75.7%) had serum/plasma phosphate determined, revealing a HypoP in 103 (15.4%) patients aged 62 [18 to 85] years. Of those, 49 patients presented phosphate <0.65 mmol/l: cases of hypophosphatemia were detected at any time of patient's ICU stay. No HypoP was observed in children. A treatment protocol existed only in 41.1% of adult ICUs, independently of ICU type, or size. Only 41/98 of the HypoP patients (29/41 of patients with phosphate <0.65 mmol/l) were receiving phosphate. CONCLUSION: HypoP is present at least in 15.4% of ICU patients, and may occur at any time during the ICU stay. The absence of phosphate repletion protocols in 60% of participating ICUs is an unexpected finding, and confirms the necessity for the development of ICU phosphate protocols and guidelines. CLINICALTRIALS IDENTIFIER: NCT04201899.

[The Early Mobilization Network]. / Netzwerk Frühmobilisierung.

BACKGROUND: Since its foundation in 2011, the German Network for Early Mobilization of mechanically ventilated intensive care patients delivered, among others, more than 90 monthly newsletters, 14 research projects, and 3 national conferences. PURPOSE: The aim of this online survey was to evaluate whether members of the Network perceived a professional benefit for themselves and their intensive cate units (ICU). METHODS: An interprofessional online survey of 303 clinicians of the Network in German speaking countries in July 2019 was undertaken. The survey included questions about newsletters, personal benefits, perceived improvements on their workplaces, and future expectations. RESULTS: The response rate was 48% (n = 145), mainly nurses and physiotherapists. The majority perceived the newsletter as good. Members reported that the network extended their professional knowledge and improved the quality of the ICUs regarding early mobilization, delirium management, and interprofessional goals. Participants expressed a wish for more workshops, case reports, webinars, and other educational possibilities. CONCLUSIONS: Members of the network Early Mobilization perceived a personal and professional benefit. The network supported quality improvements projects in ICUs. The progress of the network may serve as an example for development of other professional networks.

Sugammadex and neostigmine dose-finding study for reversal of residual neuromuscular block at a train-of-four ratio of 0.2 (SUNDRO20)†,.

BACKGROUND: The aim of this dose-finding study was to evaluate the dose-response relationship of sugammadex and neostigmine to reverse a commonly observed level of incomplete recovery from rocuronium-induced neuromuscular block, that is, a train-of-four ratio (TOFR) ≥0.2. METHODS: Ninety-nine anaesthetized patients received rocuronium 0.6 mg kg(-1) i.v. for tracheal intubation and, if necessary, incremental doses of 0.1-0.2 mg kg(-1). Neuromuscular monitoring was performed by calibrated electromyography. Once the TOFR recovered to 0.2, patients were randomized to receive sugammadex (0.25, 0.5, 0.75, 1.0, or 1.25 mg kg(-1) i.v.), neostigmine (10, 25, 40, 55, or 70 µg kg(-1) i.v.), or saline (n=9 per group). Primary and secondary end points were the doses necessary to restore neuromuscular function to a TOFR≥0.9 with an upper limit of 5 and 10 min for 95% of patients, respectively. RESULTS: Neostigmine was not able to fulfil the end points. Based on the best-fitting model, the sugammadex dose estimation for recovery to a TOFR≥0.9 for 95% of patients within 5 and 10 min was 0.49 and 0.26 mg kg(-1), respectively. CONCLUSION: A residual neuromuscular block of a TOFR of 0.2 cannot be reversed reliably with neostigmine within 10 min. In the conditions studied, substantially lower doses of sugammadex than the approved dose of 2.0 mg kg(-1) may be sufficient to reverse residual rocuronium-induced neuromuscular block at a recovery of TOFR≥0.2. CLINICAL TRIAL REGISTRATION: NCT01006720.

Effects of single-shot and steady-state propofol anaesthesia on rocuronium dose-response relationship: a randomised trial.

BACKGROUND: Similar to volatile anaesthetics, propofol may influence neuromuscular transmission. We hypothesised that the administration of propofol influenced the potency of rocuronium depending on the duration of the administration. METHODS: After consent, patients scheduled for elective surgery randomly received rocuronium either after induction of anaesthesia with propofol (2 min of propofol, n = 36) or after 30 min of propofol infusion (30 min of propofol, n = 36). Remifentanil was given in both groups. Neuromuscular monitoring was performed by calibrated electromyography. The dose-response relationship of rocuronium was determined with a single-bolus technique (0.07, 0.1, 0.15, 0.2, 0.3 and 0.45 mg/kg rocuronium). The primary endpoints were the ED50 and ED95 of rocuronium after 2 and 30 min propofol. Data are presented as means with (95% confidence interval). The trial is registered with the Eudra-CT: 2009-012815-16. RESULTS: A total of 72 patients were included. Time to maximal neuromuscular blockade was significantly shorter in patients after 30 min of propofol [3.3 min (2.9-3.7)] compared with patients anaesthetised with 2 min of propofol [4.6 min (4.0-5.2)]. After 30 min of propofol, the slope of the dose-response curve was significantly steeper (30 min of propofol: 4.34 [3.62-5.05]; 2 min of propofol: [3.34 (2.72-3.96)], resulting in lower ED95 values of rocuronium (30 min of propofol: 0.287 mg/kg [0.221-0.368]; 2 min of propofol [0.391 mg/kg (0.296-0.520)]. The ED50 were not different between groups. CONCLUSION: The potency of rocuronium was significantly enhanced after propofol infusion for 30 min. Estimates of potency those are usually determined during steady-state anaesthesia might underestimate rocuronium requirements for endotracheal intubation at the time of induction.

Block of postjunctional muscle-type acetylcholine receptors in vivo causes train-of-four fade in mice.

BACKGROUND: Train-of-four (TOF) fade during nerve-mediated muscle contraction is postulated to be attributable to inhibition of prejunctional nicotinic α3ß2 acetylcholine receptors (nAChRs), while decrease of twitch tension is attributable to block of postjunctional muscle nAChRs. The validity of these presumptions was tested using specific prejunctional and postjunctional nAChR antagonists, testing the hypothesis that fade is not always a prejunctional phenomenon. METHODS: Pentobarbital anaesthetized mice had TOF fade measured after administration of: either 0.9% saline; the prejunctional α3ß2 nAChR antagonist, dihydro-ß-erythroidine (DHßE); the postjunctional nAChR antagonists, α-bungarotoxin (α-BTX) or α-conotoxin GI; and a combination of α-BTX and DHßE; or a combination of α-conotoxin GI and DHßE. RESULTS: Saline caused no neuromuscular changes. Administration of muscle nAChR antagonists, α-BTX or α-conotoxin GI caused significant decrease of twitch tension and TOF fade compared with baseline (P<0.01). DHßE alone caused no change of twitch tension or fade even after 90 min, but its coadministration with α-BTX or α-conotoxin GI significantly accelerated the onset of paralysis and degree of fade compared with α-BTX or α-conotoxin GI alone (P<0.01). CONCLUSIONS: Occupation of postjunctional nAChRs alone by α-BTX or α-conotoxin GI causes fade. As the prejunctional effects of DHßE on fade became manifest only when co-administered with α-BTX or α-conotoxin GI, specific inhibition of prejunctional nAChR alone is not necessary and sufficient to cause fade. Fade observed during repetitive nerve stimulation can be because of block of either postjunctional nAChRs alone, or block of prejunctional and postjunctional nAChRs together.

Postoperative impairment of motor function at train-of-four ratio ≥0.9 cannot be improved by sugammadex (1 mg kg-1).

BACKGROUND: A train-of-four ratio (TOFR) ≥0.9 measured by quantitative neuromuscular monitoring is accepted as an indication of sufficient neuromuscular recovery for extubation, even though many postsynaptic acetylcholine receptors may still be inhibited. We investigated whether antagonism with sugammadex after spontaneous recovery to TOFR≥0.9 further improves muscle function or subjective well-being. METHODS: Following recovery to TOFR≥0.9 and emergence from anaesthesia, 300 patients randomly received either sugammadex 1.0 mg kg(-1) or placebo. Fine motor function (Purdue Pegboard Test) and maximal voluntary grip strength were measured before and after surgery (before and after test drug administration). At discharge from the postanaesthesia care unit, well-being was assessed with numerical analogue scales and the Quality-of-Recovery Score 40 (QoR-40). RESULTS: Patients' fine motor function [6 (sd 4) vs 15 (3) pegs (30 s)(-1), P<0.05] and maximal voluntary grip strength (284 (126) vs 386 (125) N, P<0.05) were significantly lower after anaesthesia compared with the pre-anaesthesia baseline. After sugammadex or placebo, motor function was significantly improved in both groups but did not reach the preoperative level. There was no difference between groups at any time. Global well-being was unaffected (QoR-40: placebo, 174 vs 185; sugammadex, 175 vs 186, P>0.05). CONCLUSIONS: Antagonizing rocuronium at TOF≥0.9 with sugammadex 1.0 mg kg(-) (1) did not improve patients' motor function or well-being when compared with placebo. Our data support the view that TOFR≥0.9 measured by electromyography signifies sufficient recovery of neuromuscular function. CLINICAL TRIAL REGISTRATION: The trial is registered at ClinicalTrials.gov (NCT01101139).

[Effect of a multifunctional instrument (HF scissors) in parotis surgery]. / Effekte eines multifunktionalen Instruments (HF-Schere) in der Parotischirurgie.

PROBLEM: Lateral parotidectomy is a demanding surgical procedure and requires a large number of instruments with a high frequency (HF) of alternating. Many functions, such as preparing, spreading, coagulating and cutting could be combined by using scissors with an integrated function of bipolar coagulation. This study has targeted an investigation of technical application, influence on surgery time, frequency of HF application and change of instruments. MATERIAL AND METHODS: In the period between 01 April 2011 and 30 September 2012 (18 months) 35 procedures of lateral parotidectomy in 35 patients were investigated. In all cases lateral parotidectomy was carried out with a similar technique (modified extracapsular preparation). Workflow data were used from a control group in the period between 01 January 2009 and 31 December 2010 (24 months). The following parameters from both groups were documented and evaluated: incision-suture times (subdivided into nine sections of the procedure), change of instruments, period of application for HF function and early facial nerve function (6 h and 6 days after surgery according to House-Brackmann). Additionally, in the HF+ group a questionnaire that facilitated subjective evaluation of instruments was analyzed. RESULTS: It was possible to perform the surgery in both groups with neither technical nor surgical intraoperative complications. Incision-suture times showed an average reduction of 31.6 min (34.8 %) in the HF+ group. There was a reduction in the change of instruments compared to a conventional group (CONV) by up to 62.7 %. With the deployment of HF scissors there was a clear increase in the use of HF surgery by more than 100 % when comparing incision-suture times. Evaluation of both groups according to House-Brackmann showed a similar postoperative facial nerve function. The surgeons involved were of the opinion that in all 35 surgeries with HF scissors the intervention was easier and more comfortable. DISCUSSION: The use of HF scissors is appropriate for parotid gland surgery and can be used in all steps of the procedure. Incision-suture time can be reduced and the ergonomics of the intervention can be improved. Up to now no negative effects have been found in the quality of the results.

A Generic Integrated Physiologically based Whole-body Model of the Glucose-Insulin-Glucagon Regulatory System.

Models of glucose metabolism are a valuable tool for fundamental and applied medical research in diabetes. Use cases range from pharmaceutical target selection to automatic blood glucose control. Standard compartmental models represent little biological detail, which hampers the integration of multiscale data and confines predictive capabilities. We developed a detailed, generic physiologically based whole-body model of the glucose-insulin-glucagon regulatory system, reflecting detailed physiological properties of healthy populations and type 1 diabetes individuals expressed in the respective parameterizations. The model features a detailed representation of absorption models for oral glucose, subcutaneous insulin and glucagon, and an insulin receptor model relating pharmacokinetic properties to pharmacodynamic effects. Model development and validation is based on literature data. The quality of predictions is high and captures relevant observed inter- and intra-individual variability. In the generic form, the model can be applied to the development and validation of novel diabetes treatment strategies.CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e65; doi:10.1038/psp.2013.40; published online 14 August 2013.

[Instrument navigation in ensonasal sinus surgery]. / Instrumentennavigation in der endonasalen Stirnhöhlenchirurgie: Gibt es eine Operation unter "reiner Navigationsführung"?

BACKGROUND: It is to be expected that, microsurgical operations in ENT must be partially performed without direct vision, e. g. without the possibility of controlling the preparation progress. This study provides a clinical example of how instrument navigation may be used in a safe and reasonable manner to the benefit of treatment quality. It is assumed that a median frontal sinus drainage procedure may be performed by means of a tracked sinus drill using solely instrument navigation. MATERIAL AND METHODS: The sinus drill was registered using an optoelectric navigation system. An optical registration device was attached to the drill. In the period from 1 December 2011 to 30 April 2012 (5 months) 24 patients underwent a median frontal sinus drainage. 12 of the surgeries were performed under the condition operation navigation. The other 12 surgeries were performed using solely instrument navigation. RESULTS: When applying mode Instrument Navigation (IN), a significantly reduced incision-to-suture time was registered within both groups. Within the group Draf IIB, it was reduced to 68.5% (from 67.1 min to 46.0 min). Resection efficiency, i. e., the ratio between the width of the frontal sinus ostium and the required total surgery time, widely differed to the benefit of group IN. Within both groups, the questionnaire revealed a high level of confidence in Surgical Management and Guidance Systems (SMGS) functionalities (100%). CONCLUSION: The present study was designed to show for the first time a median frontal sinus drainage under the condition solely instrument navigation.

[Interdisciplinary teleconsultation: first practical experiences with 100 patients]. / Interdisziplinäre Telekonsultation: Erste praktische Erfahrungen mit 100 Patienten.

UNLABELLED: PROBLEM DEFINITION: Increasing specialization can be observed in the various medical fields and as a consequence there is little professional exchange between ear nose and throat (ENT) specialists and general practitioners. At the same time there has been significant technological development in telemedicine over the last 5 years; however, this potential is not being sufficiently exploited. The objective of this project is to implement a practicable solution for teleconsulation between ENT specialists and general practitioners. MATERIALS AND METHODS: The connection is based on a secure broadband internet connection, the corresponding server structure and a video endoscopic system. In the period from 01 January 2011 to 30 June 2012 (18 months) a total of 102 patients were included in the study in which 4 general practitioners and 5 ENT specialists participated. The protocol comprised the following parameters: indications and typical questions, number of patients presenting to the ENT specialist due to the available teleconsultation service (CBO), number of patients referred to the ENT specialist after teleconsultation (CIO), assessment of the quality of the additional expert opinion (LOQ GP), assessment of the accuracy of the specialist physician tele-diagnosis (TDS-FA) and assessment of the impact of the expert physician diagnosis on the general medical treatment (COS). RESULTS: Teleconsultation was most frequently used for diagnostics on tonsils (37% of the presented cases), the external auditory canal (32%) and the inner nose (15%). Of the patients analyzed were 53.9% presented to the ENT specialist only because the teleconsultation service provided an effortless opportunity and after teleconsultation 40.1% of the patients were referred to the ENT specialist. General practitioners assessed the benefit from the specialist opinion with 64 points. Diagnostic certainty of the specialist opinion, i.e. the validity scale of the diagnosis made, was on average 2.0. In approximately 35.3% of the cases (36 out of 102 patients) participating general practitioners documented a considerable impact of teleconsultation on the diagnosis and/or therapy. CONCLUSIONS: Teleconsultation between general practitioners and ENT specialists can provide an advantage in treatment quality and patient comfort. According to the experience gained there is a very low risk of diminishing the professional competency of ENT medicine and the involvement of the expert group in the early project stage allows a greater leeway in project implementation. This could also have an impact on future medical performance specifications. According to the ENT experts involved in the project further applications of teleconsultation are very conceivable.

[Clinical experience with navigation functions for temporal bone surgery : interim result after 40 patients]. / Klinischer Einsatz von Navigationsfunktionen in der Felsenbeinchirurgie : Zwischenbilanz nach 40 Patienten.

PROBLEM: Although robust algorithms for registration and segmentation are available, the majority of surgical approaches to the temporal bone are nowadays made without navigation assistance. Beside instrument navigation (IN), functions such as distance control (DC) and navigated control (NC) can be used. This study analyzes the application of these navigation functionalities in lateral skull base and middle ear surgery. PATIENTS AND METHODS: A total of 41 patients with an indication of temporal bone approaches were included. The navigation was realized with an optoelectric navigation system with both non-invasive and invasive markers. Parameters such as surgical time, Level of Quality (LoQ) index, and Change of Surgical Strategy (COS) index were evaluated. RESULTS: In 14.6% of patients, the conventional mode of IN was used. In 70.7% of cases, the function DC was also used. In another 14.6% of cases, the function NC was used to control the speed of the drill. The facial nerve was the dominant segmented risk structure for active navigation. The time for setup was on average 7.78 min. The LoQ index score was on average 66 points. In 17% of the patients, surgeons evaluated the assistance mode as "necessary for the surgery". No technical-related complications were recorded. CONCLUSION: This study proves the usability of navigation technology for temporal bone surgery in clinical routine. DC and NC are two additional features for higher acceptance of navigation in microscopic surgery.

[The first clinical use of an Dynamic Registration Tool for Navigation in FESS]. / Der erste klinische Einsatz einer dynamischen (Nach-) Registrierung für die Navigation in der FESS.

BACKGROUND: The effective register accuracy in an situs issues a challenge to the employment of instrument navigation in the ENT Surgery. The idea of the initially determined process Dynamic Registration Supply (DRS) is to improve the register accuracy by the automatic, and interoperability of the register. MATERIALS AND METHODS: The aim was to determine clinical use of DRS. Opto-electrical system Navigation Panel Unit, vs. 4.0.0 with the functionality DRS was used. Experiments were carried out on 95 patients who had so called FESS. The data of a control group were available to researchers. The measuring log includes among other things following parameters: retooling time, cutting-suture time, frequency of use of the navigated pointer, frequency of additional registration. RESULTS: At least once during the procedure DRS has been activated in 85 of 95 interventions (89.5). The time required increased by 15% accumulated 189 s per intervention. The most frequently used additional registration was in the region of sphenoid sinus. The surgeons underlined that out of 95 surveys in 75 cases the DRS rendered the instrument navigation more precise, while 1% of 93 cases considered this function as unwanted. CONCLUSION: The first clinical study for use of an automatic algorithm for recognition and reduction of faulty registration of a CT, navigation was successful. The findings suggest that by using automatic intraoperative registration DRS consisting inaccuracy can be reduced. In practice this means an efficient quality improvement of the Navigation.

[Influence of an auto-motorised optical navigation camera to the surgical workflow in ENT surgery]. / Die Auswirkungen einer robotergeführten Navigationskamera in der HNO-Chirurgie.

BACKGROUND: With the application of optical navigation systems an interruption of the line of sight (LOS) between navigation camera and the patient/instrument can occur. The goal of this work is the clinical evaluation of a newly developed system for automatic adjusting of an optical navigation camera (Navigation Camera Assistant, NCA). NCA is a miniature robot, which is able to position the navigation camera autonomously in 2 levels. MATERIAL AND METHODS: The influence of the NCA was examined on 128 patients: 55 procedures at the paranasal sinuses and 9 procedures at the temporal bone with the NCA were evaluated and compared with available workflow data of adequate surgeries without NCA. An optical navigation system of the 3 (rd) generation was used. The following parameters were recorded: Preparation time of the system, time of using the system, LOS-interruptions. RESULTS: The LOS-interruption decreased in the group of FESS with application of the NCA by 92%, in the group tympanic cavity by 85%. The number of corrective motions of the navigation camera was increased with application of the NCA in the group FESS by 73%, in the group tympanic cavity by 89%. The usage time of navigation increased with the application of the NCA in the group of FESS by 36%, in the group tympanic cavity by 16%. CONCLUSIONS: With a motorized navigation camera can be the interruption rate of LOS significantly improved at frontal and lateral skull base. The technical expenditure for installation of the NCA robot is little even during, for this reason there is the potential that this module can be established for the clinical practice.

[Clinical experiences with an automatic collision warning system: instrument navigation in endoscopic transnasal surgery]. / Klinische Erfahrungen mit einem Kollisionswarnsystem: Instrumentennavigation in der endo- und transnasalen Chirurgie.

PROBLEM: The goal of this work is the extension of instrument navigation with a collision warning function. With the help of an additional distance display and warning system the performance of surgical navigation systems should be improved. MATERIAL AND METHODS: The collision warning system (DCS) is an extension of an optoelectric navigation system (NPU, Karl Storz GmbH&Co.KG, Tuttlingen, Germany). The measurement of situation awareness was performed on phantom models of functional endoscopic surgery of the paranasal sinuses (FESS; Phacon, Leipzig). Altogether 450 measurement pairs for the analysis of surgical accuracy to the risk structure (frontal skull base, lamina papyracea, internal carotid artery) were available. To examine the influence on the clinical process, a prospective analysis of intraoperative complications was carried out. Of the 104 FESS patients, two groups, one of 56 patients with only navigation (NAV) and one of 48 patients (NAV+DCS), were examined. Efficiency was evaluated on the basis of times for system preparation and intraoperative application. RESULTS: A significant increase in the assumed and actual distance values between instrument tip and risk structure using the collision warning system was seen at 76%. The complication rate was more favorable for the NAV+DCS group. The time needed for preparation of the navigation system with the application of the collision warning system increased on average by 48%, or 1.2 min. However, the relation between preparation time and utilization time was approximately the same at 53.5% in the NAV group and 57.4% in the NAV+DCS group. CONCLUSIONS: This work supports the clinical use and efficiency of a collision warning system as an addition to well-known instrument navigation in endo- and transnasal surgery. The segmenting algorithm is suitable for clinical requirements.