Macht en tegenmacht in de Nederlandse asbestregulering

De overheid moet haar excuses aanbieden aan slachtoffers en hun nabestaanden voor haar nalatigheid bij het treffen van tijdige en adequate maatregelen ter beperking van het gebruik van asbest. Dat stelt Robert Frank Ruers in zijn proefschrift "Macht en tegenmacht in de Nederlandse asbestregulering". Ook pleit hij voor een terugwerkende kracht van de Wet Verjaring Personenschade. Aan het asbestverbod uit 1993 zijn conflicten tussen de asbestindustrie, de overheid, de vakbeweging en de slachtoffers voorafgegaan. De overheid was lange tijd nauwelijks bereid beperkingen aan het asbestgebruik te stellen. Asbestslachtoffers, zo’n bekende 10.000 slachtoffers, waarschijnlijk nog niet de helft van het uiteindelijke aantal, hebben pas recent aan invloed gewonnen. Ruers onderzocht vier fasen van het asbestreguleringsproces tussen 1930 – 2004 en beschrijft de strategieën van de belangrijkste partijen, hun invloed en de impact hiervan op de juridische besluitvorming. De strategie van de SP en het Comité Asbestslachtoffers heeft het reguleringsproces een beslissende wending gegeven, aldus Ruers. De internationale solidariteit tussen organisaties van asbestslachtoffers heeft bovendien haar meerwaarde bewezen op het gebied van historische kennisontwikkeling en juridische slagkracht. Behalve voor de terugwerkende kracht van de Wet Verjaring Personenschade en de excuses pleit hij voor een op de wet gebaseerde algehele asbestinventarisatie

Broadband hyperspectral imaging for breast tumor detection using spectral and spatial information

Complete tumor removal during breast-conserving surgery remains challenging due to the lack of optimal intraoperative margin assessment techniques. Here, we use hyperspectral imaging for tumor detection in fresh breast tissue. We evaluated different wavelength ranges and two classification algorithms; a pixel-wise classification algorithm and a convolutional neural network that combines spectral and spatial information. The highest classification performance was obtained using the full wavelength range (450-1650nm). Adding spatial information mainly improved the differentiation of tissue classes within the malignant and healthy classes. High sensitivity and specificity were accomplished, which offers potential for hyperspectral imaging as a margin assessment technique to improve surgical outcome. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Erfassung der Verwendung von Wunddrainagen in der Dermatochirurgie im stationären und ambulanten Sektor durch Mitglieder der DGDC

Hintergrund: Das Thema der Wunddrainage ist ein Bereich in der Medizin, welcher häufig Anwendung bei operativen Eingriffen findet. Bis heute existieren jedoch keine zielgerichteten Indikationen für den Einsatz einer Wunddrainage. Noch immer wird die Diskussion über die Notwendigkeit einer Drainage kontrovers geführt und es liegen nur sehr wenige publizierte Daten zu diesem Thema im Fachbereich der Dermatochirurgie vor. Ziel der Arbeit: Mit Hilfe der neu gewonnenen Daten bezüglich der Verwendung von Wunddrainagen der Mitglieder der „Deutschen Gesellschaft für Dermatochirurgie“ (DGDC) sollen unter Einbezug der aktuellen Fachliteratur Ergebnisse erarbeitet werden, die einer Optimierung der Verwendung von Wunddrainagen dienen. Außerdem sollen Risikofaktoren ermittelt werden, die das Auftreten von Komplikationen beim Gebrauch von Drainagen begünstigen sowie mögliche Unterschiede zwischen ambulant und stationär tätigen Dermatochirurgen festgestellt werden. Dies dient der Erfassung der Anwendungskriterien, Anwendungshäufigkeiten und Anwendungsfaktoren von Wunddrainagen im dermatochirurgischen Bereich. Methode: Am 20.07.2017 wurde der Online-Fragebogen 10 Testpersonen als Pilotaussendung zugestellt. Zum Zeitpunkt des Versands hatte die DGDC 1094 Mitglieder. Die definitive Aussendung erfolgte dann am 14.09.2017 an 965 Mitglieder der DGDC, da von den restlichen Mitgliedern keine E-Mail-Adresse existierte. 203 Mailer Daemons kamen zurück, sodass effektiv 762 Personen den Fragebogen erhielten. Davon haben insgesamt 97 Personen geantwortet, was eine Rücklaufquote von 12,73 % bedeutet. Die Beantwortung der Fragen sowie die Auswertung der Fragebögen erfolgten anonymisiert. Ergebnisse: Von den insgesamt 97 Dermatochirurgen, welche auf den Fragebogen geantwortet haben, verwenden 49 Personen Wunddrainagen. Dies entspricht einem prozentualen Anteil von 50,52 %. Die im Fragebogen aufgelisteten Drainagesysteme beinhalten Niedervakuum-, Hochvakuum-, Redon-, Spül-Saug- und Laschen-Drainagen. Am häufigsten davon wird das Redon-Drainagesystem verwendet (89,80 %). Im Hinblick auf die Einrichtung wurde ebenfalls differenziert. Die Ergebnisse zeigten dabei, dass Kliniken signifikant häufiger Wunddrainagen verwenden als Praxen (p = 0,000). Die Verwendung einer Drainage machen die DGDC Mitglieder hauptsächlich von den Faktoren der Operationsgröße (81,63 %) sowie dem komplexen Wundverschluss (75,51 %) abhängig, weniger aber von der Operationsdauer (22,45 %). Zu den Wirkungen, die von einer Drainage erwartet werden, zählen hauptsächlich die Vermeidung von Hämatomen sowie Seromen und die verbesserte Wundheilung, besonders im Rahmen umfangreicher Lappenplastiken. Ältere Patienten (> 60. Lebensjahr) sowie Patienten mit Gefäßerkrankungen (CVI, pAVK o.a.) konnten nicht als Risikogruppen identifiziert werden (0,00 %), während Adipositas-Patienten (24,49 %) neben Rauchern und Diabetikern (jeweils 12,24 %) die höchste Risikogruppe hinsichtlich des Auftretens von Komplikationen ergaben. Die Ergebnisse zeigten, dass Schmerzen die relevanteste Problematik bezüglich Drainage-assoziierten Komplikationen darstellten (36,73 %). Wundinfektionen beobachteten 10,20 % der Befragten, was für den Fachbereich der Dermatochirurgie einen vergleichsweise hohen Wert bedeutet. Schlussfolgerungen: Es stellte sich heraus, dass das Legen einer Drainage hauptsächlich von der Operationsgröße, aber auch von individuellen Faktoren wie beispielsweise der Tiefe und Lokalisation der Wunde abhängig gemacht wird. Technische Komplikationen konnten nicht festgestellt werden, weshalb die Handhabung der Wunddrainage keine Problematik zu beinhalten scheint. Nachteilig sind allerdings die beim Patienten entstehenden Schmerzen im Zusammenhang mit Wunddrainagen. Aufgrund der Tatsache, dass sich für den Fachbereich der Dermatochirurgie ein erhöhter Wundinfektionswert herausgestellt hat, müssen zukünftig Möglichkeiten erhoben werden, welche das Infektionsrisiko senken können.Registration of the use of wound drains in dermatological surgery in the stationary and ambulant sector by members of the DGDC Background: The subject of wound drainage is an area in medicine that is frequently used in surgical procedures. But even today, there are still no specific indications for the use of drains. Up to now, the discussion about the need of drains is controversial and there are only a few published data in the dermatosurgical field. Aim: With the help of the newly acquired data concerning the use of drains by members of the DGDC, results are to be worked out with reference to the current literature, to improve the use of drainage systems. Furthermore, risk factors should also be identified which favour the occurence of complications by using a drainage as well as possible differences between dermatosurgeons working in stationary or ambulant sectors. This serves to registrate the application criteria, application frequencies and application factors by using wound drainages in dermatological surgery. Methods: On 20th july 2017 an online-questionnaire was sent to 10 test persons as a pilot mailing. By the time of transmission, the DGDC had 1094 members. The final mailing was sent on 14th september 2017 to 965 members of the DGDC due to the fact that no e-mail address existed from the remaining members. 203 mailer daemons returned, so that effectively 762 people received the questionnaire. A total amount of 97 people answered the questionnaire, which means a response rate of 12,73 %. The answers to the questions and the evaluation of the questionnaires were made anonymously. Results: Out of the total 97 dermatosurgeons, who answered the questionnaire, 49 people use drains. This corresponds to a percentage share of 50,52 %. The drainage systems listed in the questionnaire include low vakuum-, high vakuum-, Redon-, Flush-Suction-drains and Corrugated drains. Out of them the Redon drainage is the most frequently used one (89,80 %). The results showed that clinics use drainages significantly more often than medical practices (p = 0,000). The use of drainage by members of the DGDC mainly depends on the factors of operation size (81,63 %) and complex wound closure (75,51 %), but less on the duration of the operation (22,45 %). The effects expected from wound drainage are mostly the prevention of hematomas and seromas and the improved wound healing, especially in the context of extensive flap plasty. Older patients (> 60 years of age) and patients with vascular diseases (CVI, pAVK and similar) could not be identified as risk groups (0,00 %), whereas obesity (24,49 %), beside smokers and diabetes (each 12,24 %), is the highest risk group regarding the occurrence of complications. The results showed that pain was the most relevant problem in conjunction with drain-associated complications (36,73 %). Wound infections are observed by 10,20 % of the interviewed persons, which means a comparatively high value for the area of dermatosurgical interventions. Conclusion: It turned out that the placement of drainage depends essentially on the size of the operation, but also on individual factors such as the depth and location of the wound. Technical complications could not be detected (0,00 %), therefore the handling of the wound drainage does not seem to be a problem. However, disadvantageous is the pain the patient suffers by using a drain. Due to the fact that an increased wound infection rate has been found for the dermatosurgery, possibilities must be investigated in the future, which can reduce the risk of infection

Method for coregistration of optical measurements of breast tissue with histopathology : the importance of accounting for tissue deformations

For the validation of optical diagnostic technologies, experimental results need to be benchmarked against the gold standard. Currently, the gold standard for tissue characterization is assessment of hematoxylin and eosin (H&E)-stained sections by a pathologist. When processing tissue into H&E sections, the shape of the tissue deforms with respect to the initial shape when it was optically measured. We demonstrate the importance of accounting for these tissue deformations when correlating optical measurement with routinely acquired histopathology. We propose a method to register the tissue in the H&E sections to the optical measurements, which corrects for these tissue deformations. We compare the registered H&E sections to H&E sections that were registered with an algorithm that does not account for tissue deformations by evaluating both the shape and the composition of the tissue and using microcomputer tomography data as an independent measure. The proposed method, which did account for tissue deformations, was more accurate than the method that did not account for tissue deformations. These results emphasize the need for a registration method that accounts for tissue deformations, such as the method presented in this study, which can aid in validating optical techniques for clinical use. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License

Monitoring of tumor response to Cisplatin using optical spectroscopy

INTRODUCTION Anatomic imaging alone is often inadequate for tuning systemic treatment for individual tumor response. Optically based techniques could potentially contribute to fast and objective response monitoring in personalized cancer therapy. In the present study, we evaluated the feasibility of dual-modality diffuse reflectance spectroscopy-autofluorescence spectroscopy (DRS-AFS) to monitor the effects of systemic treatment in a mouse model for hereditary breast cancer. METHODS Brca1(-/-); p53(-/-) mammary tumors were grown in 36 mice, half of which were treated with a single dose of cisplatin. Changes in the tumor physiology and morphology were measured for a period of 1 week using dual-modality DRS-AFS. Liver and muscle tissues were also measured to distinguish tumor-specific alterations from systemic changes. Model-based analyses were used to derive different optical parameters like the scattering and absorption coefficients, as well as sources of intrinsic fluorescence. Histopathologic analysis was performed for cross-validation with trends in optically based parameters. RESULTS Treated tumors showed a significant decrease in Mie-scattering slope and Mie-to-total scattering fraction and an increase in both fat volume fraction and tissue oxygenation after 2 days of follow-up. Additionally, significant tumor-specific changes in the fluorescence spectra were seen. These longitudinal trends were consistent with changes observed in the histopathologic analysis, such as vital tumor content and formation of fibrosis. CONCLUSIONS This study demonstrates that dual-modality DRS-AFS provides quantitative functional information that corresponds well with the degree of pathologic response. DRS-AFS, in conjunction with other imaging modalities, could be used to optimize systemic cancer treatment on the basis of early individual tumor response

Diffuse reflection spectroscopy at the fingertip:design and performance of a compact side-firing probe for tissue discrimination during colorectal cancer surgery

Optical technologies are widely used for tissue sensing purposes. However, maneuvering conventional probe designs with flat-tipped fibers in narrow spaces can be challenging, for instance during pelvic colorectal cancer surgery. In this study, a compact side-firing fiber probe was developed for tissue discrimination during colorectal cancer surgery using diffuse reflectance spectroscopy. The optical behavior was compared to flat-tipped fibers using both Monte Carlo simulations and experimental phantom measurements. The tissue classification performance was examined using freshly excised colorectal cancer specimens. Using the developed probe and classification algorithm, an accuracy of 0.92 was achieved for discriminating tumor tissue from healthy tissue

Monitoring of tumor radio frequency ablation using derivative spectroscopy

Despite the widespread use of radio frequency (RF) ablation, an effective way to assess thermal tissue damage during and after the procedure is still lacking. We present a method for monitoring RF ablation efficacy based on thermally induced methemoglobin as a marker for full tissue ablation. Diffuse reflectance (DR) spectra were measured from human blood samples during gradual heating of the samples from 37 to 60, 70, and 85°C. Additionally, reflectance spectra were recorded real-time during RF ablation of human liver tissue ex vivo and in vivo. Specific spectral characteristics of methemoglobin were extracted from the spectral slopes using a custom optical ablation ratio. Thermal coagulation of blood caused significant changes in the spectral slopes, which is thought to be caused by the formation of methemoglobin. The time course of these changes was clearly dependent on the heating temperature. RF ablation of liver tissue essentially led to similar spectral alterations. In vivo DR measurements confirmed that the method could be used to assess the degree of thermal damage during RF ablation and long after the tissue cooled