O exame de palpação é um procedimento no qual um profissional da saúde pressiona uma região específica do corpo de um paciente com os dedos a fim de detectar a presença ou ausência de características e anormalidades sob a pele. Um simulador que forneça subsídios para o treinamento deste procedimento pode contribuir para o aprendizado da técnica e o aprimoramento de sua execução em pacientes, além de, dentre outras vantagens, eliminar a necessidade de exposição de pacientes aos riscos das situações reais, minimizar o uso de objetos físicos e tornar possível a simulação de diferentes casos e ações. O objetivo principal deste trabalho consiste em desenvolver um simulador de palpação mamária com retorno háptico realista. No contexto do exame de palpação, existe uma lacuna no que concerne a definição de técnicas e parâmetros de retorno de força que ofereçam uma experiência mais realista de interação para o usuário. Após uma revisão sistemática da literatura foi feito o mapeamento dos principais parâmetros para representar diferentes nódulos durante o treinamento virtual visando ao diagnóstico de anomalias mamárias. Tais parâmetros foram equacionados com a finalidade de obter uma representação realista em um dispositivo háptico. Além disso, interfaces foram implementadas para permitir a geração de casos com a variação desses parâmetros referentes aos nódulos (tamanho, consistência, localização e contorno). Os resultados obtidos a partir de uma avaliação com uma profissional da medicina mostraram que o retorno de força aplicado a cada uma das características foi realista para todos os parâmetros, com limitação na representação de nódulos espiculados, que deve ser melhorada. Além de contribuir com a área de Computação no sentido de ter definido técnicas e parâmetros de retorno de força importantes para a simulação de exames de palpação, o trabalho disponibiliza uma ferramenta que pode contribuir para a aquisição efetiva da habilidade necessária para a execução do procedimento em questão / Palpation exam is a procedure in which a health care professional presses a specific region of a patient\'s body with the fingers in order to detect the presence of features and abnormalities under the skin. A simulator that aids the training this procedure may contribute to the learning of the technique and the improvement of its implementation in real patients. The main objective of the Master\'s degree work proposed in this paper is to develop a breast palpation simulator with haptic feedback. The results of a Systematic Review conducted in order to assess the state-of-art of the simulation of the palpation procedure showed that despite being a new area, there are already many innovative works that received positive reviews. However, in the context of palpation examination, a gap exists regarding the definition of techniques and force feedback parameters to provide a more realistic experience to the user. After a Systematic Review from the literature the mapping of the main parameters was done to represent different nodules during the virtual training for the diagnosis of breast abnormalities. These parameters were transformed into equations with the goal of obtaining a realistic representation on a haptic device. Besides, user interfaces were implemented to allow the creation of cases with the variation of the parameters relative to the nodules (size, consistency, localization and contour). The results obtained from an assessment done with a medical professional showed that the force feedback applied to each one of the characteristics was realistic to all the parameters, with limitations on the representation of spiculated nodules, which must be improved. Aside from the contribution to the Computing area in the sense that force feedback techniques and parameters important to the simulation of palpation exams were defined, this work offers a tool that can contribute to the effective acquisition of the necessary skills to the execution of the procedure in question

This work describes the development of an optical probe for measuring movement of tissue particles deep inside which are loaded by an ultrasound remote palpation device. The principle of the method is that ultrasound force which can be applied inside the tissue makes the tissue particles vibrate and this vibration phase-modulates the light intercepting the insoniified region which results in a modulated speckle intensity on detection outside the object. This speckle intensity modulation detected through the measured intensity autocorrelation is a measure of the vibration amplitude. Since the vibration amplitude is related to the local elastic properties of the medium, the measured modulation depth in intensity autocorrelation can be used to map the elastic property in the insonified region. In this work, first the ultrasound induced force is calculated for both plane and focused ultrasound beams, and converted to amplitude of vibration and refractive index modulation, solving the forward elastography equation. Light propagation inside an insonified object is modelled using Monte Carlo simulation and the amplitude and intensity correlations are computed. The modulation depth on the autocorrelation is estimated and shown that it is inversely correlated to the local elastic modulus and optical absorption coefficient. It is further shown that whereas the variation in modulation depth is linear with respect to absorption coefficient, the same variation with elastic property is nonlinear. These results are verified experimentally in a tissue mimicking phantom. The phantom was constructed out of poly vinyl alcohol(PVA) whose optical, mechanical and acoustic properties are independently controlled. It is also shown that for loading with focused ultrasound beam the displacement is almost along the ultrasound transducer axis and therefore the contribution from refractive index modulation alone can be ascertained by probing the insonified perpendicular to the transducer axis. This helps one to find the contribution to the modulation depth from the ultrasound-induced vibration, which can be used to compute a quantitative estimate of the elastic modulus from the modulation depth.

O laser de baixa intensidade tem sido utilizado atualmente como terapia alternativa para alívio da dor em disfunções musculares e articulares por induzirem um efeito analgésico, antiinflamatório e biomodulador das funções fisiológicas celulares. O objetivo desse estudo foi avaliar o efeito do laser de GaAlAs (780nm) na dor à palpação dos músculos masseter e temporal anterior e articulação temporomandibular (ATM), amplitude dos movimentos mandibulares e atividade eletromiográfica dos músculos masseter e temporal anterior em pacientes com disfunção temporomandibular (DTM). As aplicações foram feitas no músculo temporal e masseter e na ATM 2 vezes/semana (durante 4 semanas). 48 pacientes com dor miofascial e artralgia distribuídos aleatoriamente entre tratamento real e placebo e entre doses energéticas de 25 J/cm² e 60 J/cm² foram avaliados utilizando-se uma Escala Analógica Visual (VAS) e um paquímetro digital antes, imediatamente após a última aplicação e 30 dias após o tratamento com laser. A eletromiografia de superfície foi realizada em máximo apertamento voluntário em rolos de algodão e máximo apertamento voluntário em posição intercuspidal antes e após a laserterapia. Os resultados mostraram que não houve diferença estatística significante na atividade eletromiográfica na comparação entre os grupos antes e após o tratamento com laser. Em relação à dor na palpação, houve diferença significante antes e após o tratamento em todos os grupos. A diminuição dos níveis de dor muscular foi mais acentuada nas pontas ativas, entretanto, não houve diferença estatística significante entre o grupo real e placebo. A dor articular mostrou melhora significante apenas na palpação do pólo lateral da ATM direita nos grupos ativos. A amplitude dos movimentos mostrou melhora no grupo ativo, principalmente, na dose de 60 J/cm². Em conclusão, o laser de baixa intensidade não promoveu mudanças na atividade eletromiográfica. Embora tenha sido encontrada uma superioridade da terapia laser em relação aos grupos placebos, não houve diferença estatística significante entre todos os grupos. / Low intensity laser have been used currently as an alternative pain-relief therapy for muscle and joint pain since it induces analgesic, anti-inflammatory and biomodulation effects of the physiological cell functions. The purpose of this study was to evaluate the effect of GaAlAs laser (780nm) on pain to palpation of the masseter and anterior temporalis muscles and the temporomandibular joint (TMJ), amplitude of the mandibular movements and electromyographic activity of the masseter and anterior temporalis muscles in patients with temporomandibular disorders (TMD). The laser was applied on the temporalis, masseter muscles and TMJ twice a week (during four weeks). Forty-eight patients with miofascial pain and arthralgia were randomly assigned between real and placebo treatment and between the energetic doses of 25 J/cm² and 60 J/cm², and were evaluated using Visual Analogue Scale (VAS) and digital paquimeter before, immediately after the final application, and 30 days after the laser treatment. Surface electromyography was performed with maximum voluntary clench on cotton rolls and maximum voluntary clench in intercuspal before and after laser therapy. The results show there were no significant statistical differences in the electromyographic activity between the groups before and after laser treatment. As to the pain at palpation, there was a significant difference before and after treatment in every group. There were sharper reductions in muscle pain level for the active probes; however, there was no significant statistical difference between the real and placebo groups. Joint pain showed significant improvement only in the palpation of the lateral pole of right TMJ in the active groups. The amplitude of the movements showed improvement in the active group, mainly, in the dose of 60 J/cm². As conclusion, low intensity laser did not promote any changes in the electromyographic activity. Although this study has found a superiority of laser therapy over placebo, there were no statistically significant differences between all groups.

Minimally invasive surgery (MIS) consists in operating through small incisions in which a camera and adapted instruments are inserted. It allows to perform many interventions with reduced trauma for the patient. One of these is the ablation of peripheral pulmonary nodules.<p><p>Nevertheless, the means for detecting nodules during MIS are limited. In fact, because of the lack of direct contact, the surgeon cannot palpate the lung to find invisible lesions, as he would do in classical open surgery. As a result, only clearly visible nodules can be treated by MIS presently.<p><p>This work aims at designing, building and controlling a teleoperated palpation instrument, in order to extend the possibilities of MIS in the thoracic field. Such an instrument is made of a master device, manipulated by an operator, and a slave device which is in contact with the patient and reproduces the task imposed by the master. Adequate control laws between these two parts allow to restore the operator's haptic sensation. The goal is not to build a marketable prototype, but to establish a proof of concept.<p><p>The palpation device has been designed in collaboration with thoracic surgeons on the basis of the study of the medical gesture. The specifications have been deduced through experiments with experiencied surgeons from the Erasmus Hospital and the Charleroi Civil Hospital.<p><p>A pantograph has been built to be used as the master of the palpation tool. The slave is made of a 2 degrees of freedom (dof) clamp, which can be actuated in compression and shear. The compression corresponds to vertical moves of the pantograph, and the shear to horizontal ones. Force sensors have been designed within this project to measure the efforts along these directions, both at the master and the slave side, in order to implement advanced force-feedback control laws and for validation purposes.<p><p>Teleoperation control laws providing a suitable kinesthetic force feedback for lung palpation have been designed and validated through simulations. These simulations have been realized using a realistic model of lung, validated by experienced surgeons. Among the implemented control schemes, the 3-Channel scheme, including a local force control loop at the master side, is the most efficient for lung palpation. Moreover, the increased efficiency of a 2 dof device with respect to a 1 dof tool has been confirmed. Indeed, a characteristic force profile due to the motion in 2 directions appeared in the compression force tracking, making the lesion easier to locate. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished

<p>Karcinom dojke predstavlja najče&scaron;ću malignu neoplazmu među ženskom populacijom, a po&scaron;tedna terapija dojke, preferirani je model lečenja bolesnica u ranom stadijumu bolesti. Smatra se da je optimalna hirur&scaron;ka resekciona margina 2 mm. Opisano je mnogo metoda koje služe za intraoperativnu proveru suficijentnosti resekcione hirur&scaron;ke margine i sve one imaju svoje prednosti i mane. Ciljevi ove studije bili su da se utvrdi, da li postoji statistički značajna razlika u određivanju &scaron;irine negativne resekcione hirur&scaron;ke margine izražene u milimetrima pri operacijama karcinoma dojke upotrebom palpatorne metode i intraoperativne mobilne radiografije, poređenjem nalaza merenja hiruga sa većim i manjim iskustvom u hirurgiji karcinoma dojke kao i nalaza radiologa u odnosu na patohistolo&scaron;ku ex tempore analizu. Istraživanje je sprovedeno kao retrospektivno&ndash;prospektivna studija na Klinici za operativnu onkologiju, Instituta za onkologiju Vojvodine i obuhvatilo je 150 bolesnica kod kojih je preoperativno dijagnostikovan karcinom dojke. Kriterijum za uključenje u studiju bilo je izvođenje po&scaron;tedne operacije dojke sa ili bez disekcije ipsilaterale aksile, dok su iz studije isključene bolesnice kod kojih nije bilo moguće izvesti po&scaron;tednu operaciju dojke, one sa radiolo&scaron;ki potvrđenom diseminovanom bole&scaron;ću, kao i bolesnice koje su ranije operisane zbog karcinoma iste dojke. Kod svih 150 ekstirpiranih karcinoma dojke urađena je procena &scaron;irine resekcione hirur&scaron;ke margine intraoperativno palpatornom metodom, zatim na aparatu za mobilnu digitalnu radiografiju, te radiogram analiziran od strane iskusnog i manje iskusnog hiruga u hirurgiji karcinoma dojke, kao i radiologa te upoređen sa nalazom ex tempore patohistolo&scaron;ke analize. Definitivna &scaron;irina resekcione hirur&scaron;ke margine potvrđena je na parafinskim patohistolo&scaron;kim preparatima. Srednja vrednost praćenja bolesnica, postoperativno, iznosila je 100,97 nedelja. Najveći broj bolesnica pripadao je starijoj životnoj dobi (56,67%). Preoperativna lokalizacija klinički nepalpabilnih tumora u dojci urađena je kod 52 (34,67%) bolesnice. Najče&scaron;će se tumor prezentovao kao solitarni fokus sa okolnim ognji&scaron;tima in situ karcinoma (72, 48%), dok je najče&scaron;ći histolo&scaron;ki subtip bio duktalni invazivni karcinom dojke (112 (74,67%)). Najveći broj operacija dojke okarakterisan je kao kvadrantektomija (85 (56,67)), dok je najučestalija operacija aksile bilo određivanje limfnog čvora stražara (119 (79,33%). Analizom rada aparata za mobilnu digitalnu radiografiju do&scaron;li smo do saznanja da nema statistički značajne razlike u oceni kvaliteta radiograma i &scaron;irine resekcione hirur&scaron;ke margine merene na aparatu za mobilnu digitalnu radiografiju između iskusnog hirurga i radiologa. Statistički značajna razlika nije uočena ni pri merenju &scaron;irine resekcione hirur&scaron;ke margine izražene u milimetrima na aparatu za mobilnu digitalnu radiografiju od strane iskusnog hirurga i radiologa u odnosu na ex tempore patohistolo&scaron;ku analizu, dok je ista uočena nakon definitivne patohistolo&scaron;ke analize. &Scaron;ansa doresekcije tkiva dojke nakon merenja na aparatu za mobilnu digitalnu radiografiju je 1,4 puta veća nego nakon patohistolo&scaron;ke ex tempore analize. Lokalni recidiv javio se kod jedne pacijentkinje tokom perioda praćenja. Ne postoji statistički značajna razlika u određivanju &scaron;irine resekcione hirur&scaron;ke margine izražene u milimetrima upotrebom aparata za mobilnu digitalnu radiografiju od strane iskusnog hirurga i radiologa u odnosu na patohistolo&scaron;ku ex tempore analizu, dok ista postoji nakon analize radiograma od strane manje iskusnog hirurga. Palpatorna metoda se ne može smatrati sigurnom metodom u određivanju &scaron;irine hirur&scaron;ke resekcione margine. Ne postoji statistički značajna razlika u broju doresekcije tkiva dojke između hirurga sa različitim hirur&scaron;kim iskustvom.</p> / <p>Breast cancer is the most common malignant neoplasm in the female population, and conservative breast therapy is the preferred treatment model for patients in early stages of the disease. The optimal surgical resection margin, from healthy breast tissue around the primary tumor is 2 mm. Many methods have been described that serve to check the resection margin during breast conservative surgery and all of them have their advantages and disadvantages. The aim of this study was to determine whether there was a statistically significant difference in the determination of the width of the negative resection margin expressed in millimeters in breast cancer surgery using palpatory method and intraoperative mobile specimen radiography, comparing the findings of measuring of surgeons with greater and lesser experience in breast cancer surgery as well as the findings of the radiologist in relation to histopathological ex tempore and definitive histopathological analysis. The study was conducted as a retrospective - prospective study at the Clinic for Operative Oncology, Oncology Institute of Vojvodina and included 150 patients who were preoperatively diagnosed with breast cancer. The criterion for inclusion in the study was the opportunity to perform breast conservative surgery with or without complete axillary lymph node dissection. Patients that were treated with breast amputation, those with radiological confirmed disseminated disease, as well as patients previously operated from cancer were excluded from the study. For all 150 extirpated breast cancers, an estimate of the width of the resection surgical margin was performed intraoperatively with a palpatory method, followed by measuring on device for mobile specimen digital radiography, and a radiogram was analyzed by an experienced and less experienced surgeon in breast cancer surgery, as well as by a radiologist and compared with an ex tempore histopathological analysis. The definitive width of the resection surgical margin was confirmed on histopathological preparations. The mean follow-up, postoperatively, was 100.97 weeks. The majority of patients belonged to the elderly age (56.67%). Preoperative localization of clinically impalpable breast tumors was performed in 52 (34.67%) patients. Most often the tumor was presented as a solitary focus with surrounding foci of in situ cancer (72, 48%), while the most common histological subtype was invasive ductal breast cancer (112 (74.67%)). The majority of breast operations were characterized like quadrantectomy (85 (56.67)), while the most frequent axillary surgery was the determination of the sentinel lymph node (119 (79.33%). No significant difference was observed in the evaluation of radiography quality and the width of the resection surgical margin measured on the mobile digital radiography device between the experienced surgeon and the radiologist. No statistically significant difference was observed in the measurement of the width of the resection surgical margin expressed in millimeters on the mobile digital radiography device by the experienced surgeon and radiologist versus ex tempore histopathological analysis, while the statistical difference was observed after definite histopathological analysis. The chance of breast tissue reexcision after measurement on a mobile digital radiography device is 1.4 times higher than after histopathological ex tempore analysis. Local relapse occurred in one patient during the follow-up period. There is no statistically significant difference in the determination of the width of the resection surgical margin expressed in millimeters using a mobile digital radiography device by an experienced surgeon in breast cancer surgery and radiologist with respect to histopathological ex tempore analysis. However, the statistical difference exists after radiogram analysis by a less experienced surgeon. The palpatory method cannot be considered as a safe method in determining the width of a surgical resection margin. There is no statistically significant difference in the number of breast tissue additional resections between surgeons with different surgical experience.</p>

RESUME La Trypanosomiase Humain Africaine (THA) demeure un problème de santé publique pour plusieurs pays en Afrique subsaharienne. Le contrôle de la THA est basé essentiellement sur la stratégie de dépistage actif suivi du traitement des personnes infectées. Le dépistage actif est réalisé par des unités mobiles spécialisées, bien que les services de santé fixes jouent un rôle important en détectant « passivement » des cas. Le dépistage reposait jadis sur la palpation ganglionnaire mais, depuis le développement du test d’agglutination sur carte (CATT), trois possibilités se sont offertes aux programmes de contrôle à savoir: i) continuer avec la palpation ganglionnaire ii) combiner la palpation ganglionnaire avec le CATT iii) recourir au CATT seul. Certains programmes comme celui de la République Démocratique du Congo (RDC) ont opté pour la combinaison en parallèle de la palpation ganglionnaire avec le CATT. Toute personne ayant une hypertrophie ganglionnaire cervicale et/ou un CATT positif est considéré comme suspecte de la THA. Elle sera soumise aux tests parasitologiques de confirmation à cause de la toxicité des médicaments anti-THA. Les tests parasitologiques classiques sont l’examen du suc ganglionnaire (PG), l’examen du sang à l’état frais (SF), la goutte épaisse colorée (GE). La sensibilité de cette séquence a été estimée insuffisante par plusieurs auteurs et serait à la base d’une grande perte de l’efficacité de la stratégie dépistage-traitement. D’autres techniques de concentration ont été développées comme la mini-Anion Exchange Concentration Technique (mAECT), la Centrifugation en Tube Capillaire (CTC) et le Quantitative Buffy Coat (QBC), mais ces techniques de concentration ne sont pas utilisées en routine. En RDC, une interruption des activités de contrôle en 1990 a eu comme conséquence une réémergence importante de la maladie du sommeil. Depuis 1998 les activités de contrôle ont été refinancées de manière structurée. Ce travail vise deux buts à savoir le plaidoyer pour la continuité des activités de contrôle et la rationalisation des stratégies de contrôle. Nous avons évalué l’évolution de la maladie du sommeil en rapport avec le financement, son impact sur les ménages ainsi que la communauté. L’exercice de rationalisation a porté sur les outils de dépistage et de confirmation. Nous avons d’abord évalué la validité des tests, leur faisabilité ainsi que les coûts et ensuite nous avons effectué une analyse décisionnelle formelle pour comparer les algorithmes de dépistage et pour les tests de confirmation. Pendant la période de refinancement structurel de la lutte contre la THA en RDC (1998-2003), le budget alloué aux activités a été doublé lorsqu’on le compare à la période précédente (1993-1997). Le nombre des personnes examinées a aussi doublé mais par contre le nombre des nouveaux cas de THA est passé d’un pic de 26 000 cas en 1998 à 11 000 en 2003. Le coût par personne examinée a été de 1,5 US$ et celui d’un cas détecté et sauvé à 300 US$. Pendant cette période, les activités ont été financées par l’aide extérieure à plus de 95%. Cette subvention pourrait laisser supposer que l’impact de la THA au niveau des ménages et des communautés est réduit mais lorsque nous avons abordé cet aspect, il s’est avéré que le coût de la THA au niveau des ménages équivaut à un mois de leur revenu et que la THA fait perdre 2145 DALYs dans la communauté. L’intervention par la stratégie de dépistage-traitement a permis de sauver 1408 DALYs à un coût de 17 US$ par DALYs sauvé. Ce coût classe l’intervention comme « good value for money ». Le recours au CATT seul s’est avéré comme la stratégie la plus efficiente pour le dépistage actif. Le gain marginal lorsque l’on ajoute la palpation ganglionnaire en parallèle est minime et n’est pas compensé par le coût élevé lié à un nombre important des suspects soumis aux tests parasitologiques. Les techniques de concentration ont une bonne sensibilité et leur faisabilité est acceptable. Leur ajout à l’arbre classique améliore la sensibilité de 29 % pour la CTC et de 42% pour la mAECT. Le coût de la CTC a été de 0,76 € et celui de la mAECT de 2,82 €. Le SF a été estimé très peu sensible. L’algorithme PG- GE-CTC-mAECT a été le plus efficient avec 277 € par vie sauvée et un ratio de coût-efficacité marginal de 125 € par unité de vie supplémentaire sauvée. L’algorithme PG-GE-CATT titration avec traitement des personnes avec une parasitologie négative mais un CATT positif à un seuil de 1/8 devient compétitif lorsque la prévalence de la THA est élevée. Il est donc possible dans le contexte actuel de réduire la prévalence de la THA mais à condition que les activités ne soient pas interrompues. Le recours à un algorithme recourant au CATT dans le dépistage actif et à la séquence PG-GE-CTC-mAECT est le plus efficient et une efficacité de 80%. La faisabilité et l’efficacité peut être différent d’un endroit à l’autre à cause de la focalisation de la THA. Il est donc nécessaire de réévaluer cet algorithme dans un autre foyer de THA en étude pilote avant de décider d’un changement de politique. Le recours à cet algorithme implique un financement supplémentaire et une volonté politique. SUMMARY Human African Trypanosomiasis (HAT) remains a major public health problem affecting several countries in sub-Saharan Africa. HAT control is essentially based on active case finding conducted by specialized mobile teams. In the past the population screening was based on neck gland palpation, but since the development of the Card Agglutination Test for Trypanosomiasis (CATT) three control options are available to the control program: i) neck gland palpation ii) CATT iii) neck gland palpation and CATT done in parallel . Certain programs such as the one in DRC opted for the latter, combining CATT and neck gland palpation. All persons having hypertrophy of the neck gland and/or a positive CATT test are considered to be a HAT suspect. Confirmation tests are necessary because the screening algorithms are not 100 % specific and HAT drugs are very toxic. The classic parasitological confirmation tests are lymph node puncture (LNP), fresh blood examination (FBE) and thick blood film (TBF). The sensitivity of this combination is considered insufficient by several authors and causes important losses of efficacy of the screening-treatment strategy. More sensitive concentration methods were developed such as the mini Anion Exchange Concentration Techniques (mAECT), Capillary Tube Centrifugation (CTC) and the Quantitative Buffy Coat (QBC), but they are not used on a routine basis. Main reasons put forward are low feasibility, high cost and long time of execution. In the Democratic Republic of Congo, HAT control activities were suddenly interrupted in 1990 and this led to an important re-emergence or the epidemic. Since 1998 onwards, control activities were financed again in a structured way. This works aims to be both a plea for the continuation of HAT control as well as a contribution to the rationalization of the control strategies. We analyzed the evolution of sleeping sickness in the light of its financing, and we studied its impact on the household and the community. We aimed at a rationalization of the use of the screening and confirmation tools. We first evaluated the validity of the tests, their feasibility and the cost and we did a formal decision analysis to compare screening and confirmation algorithms. The budget allocated to control activities was doubled during the period when structural aid funding was again granted (1998-2003) compared with the period before (1993-1997). The number of persons examined per year doubled as well but the number of cases found peaked at 26 000 in 1998 and dropped to 11 000 in the period afterwards. The cost per person examined was 1.5 US$ and per case detected and saved was 300 US$. The activities were financed for 95 % by external donors during this period. This subvention could give the impression that the impact of HAT on the household and the household was limited but when we took a closer look at this aspect we found that the cost at household level amounted to one month of income and that HAT caused the loss of 2145 DALYs in the community. The intervention consisting of active case finding and treatment allowed to save 1408 DALY’s at a cost of 17 US$ per DALY, putting the intervention in the class of “good value for money”. The use of CATT alone as screening test emerged as the most efficient strategy for active case finding. The marginal gain when neck gland palpation is added is minor and is not compensated by the high cost of doing the parasitological confirmation test on a high number of suspected cases. The concentration methods have a good sensitivity and acceptable feasibility. Adding them to the classical tree improves its sensitivity with 29 % for CTC and with 42 % for mAECT. The cost of CTC was 0.76 US$ and of mAECT was 2.82 US$. Sensitivity of fresh blood examination was poor. The algorithm LNP-TBF-CTC-mAECT was the most efficient costing 277 Euro per life saved and a marginal cost effectiveness ratio of 125 Euro per supplementary life saved. The algorithm LNP-TBF-CATT titration with treatment of persons with a negative parasitology but a CATT positive at a dilution of 1/8 and more becomes competitive when HAT prevalence is high. We conclude that it is possible in the current RDC context to reduce HAT prevalence on condition that control activities are not interrupted. Using an algorithm that includes CATT in active case finding and the combination LNP-TBF-CTC-mAECT is the most efficient with an efficacy of 80 %. Feasibility and efficacy may differ from one place to another because HAT is very focalized, so it is necessary to test this novel algorithm in another HAT focus on a pilot basis, before deciding on a policy change. Implementation of this algorithm will require additional financial resources and political commitment.

RESUME<p>La Trypanosomiase Humain Africaine (THA) demeure un problème de santé publique pour plusieurs pays en Afrique subsaharienne. Le contrôle de la THA est basé essentiellement sur la stratégie de dépistage actif suivi du traitement des personnes infectées. Le dépistage actif est réalisé par des unités mobiles spécialisées, bien que les services de santé fixes jouent un rôle important en détectant « passivement » des cas. Le dépistage reposait jadis sur la palpation ganglionnaire mais, depuis le développement du test d’agglutination sur carte (CATT), trois possibilités se sont offertes aux programmes de contrôle à savoir: i) continuer avec la palpation ganglionnaire ii) combiner la palpation ganglionnaire avec le CATT iii) recourir au CATT seul. Certains programmes comme celui de la République Démocratique du Congo (RDC) ont opté pour la combinaison en parallèle de la palpation ganglionnaire avec le CATT. Toute personne ayant une hypertrophie ganglionnaire cervicale et/ou un CATT positif est considéré comme suspecte de la THA. Elle sera soumise aux tests parasitologiques de confirmation à cause de la toxicité des médicaments anti-THA. Les tests parasitologiques classiques sont l’examen du suc ganglionnaire (PG), l’examen du sang à l’état frais (SF), la goutte épaisse colorée (GE). La sensibilité de cette séquence a été estimée insuffisante par plusieurs auteurs et serait à la base d’une grande perte de l’efficacité de la stratégie dépistage-traitement. D’autres techniques de concentration ont été développées comme la mini-Anion Exchange Concentration Technique (mAECT), la Centrifugation en Tube Capillaire (CTC) et le Quantitative Buffy Coat (QBC), mais ces techniques de concentration ne sont pas utilisées en routine. <p>En RDC, une interruption des activités de contrôle en 1990 a eu comme conséquence une réémergence importante de la maladie du sommeil. Depuis 1998 les activités de contrôle ont été refinancées de manière structurée. <p>Ce travail vise deux buts à savoir le plaidoyer pour la continuité des activités de contrôle et la rationalisation des stratégies de contrôle. Nous avons évalué l’évolution de la maladie du sommeil en rapport avec le financement, son impact sur les ménages ainsi que la communauté. L’exercice de rationalisation a porté sur les outils de dépistage et de confirmation. Nous avons d’abord évalué la validité des tests, leur faisabilité ainsi que les coûts et ensuite nous avons effectué une analyse décisionnelle formelle pour comparer les algorithmes de dépistage et pour les tests de confirmation.<p>Pendant la période de refinancement structurel de la lutte contre la THA en RDC (1998-2003), le budget alloué aux activités a été doublé lorsqu’on le compare à la période précédente (1993-1997). Le nombre des personnes examinées a aussi doublé mais par contre le nombre des nouveaux cas de THA est passé d’un pic de 26 000 cas en 1998 à 11 000 en 2003. Le coût par personne examinée a été de 1,5 US$ et celui d’un cas détecté et sauvé à 300 US$. Pendant cette période, les activités ont été financées par l’aide extérieure à plus de 95%. Cette subvention pourrait laisser supposer que l’impact de la THA au niveau des ménages et des communautés est réduit mais lorsque nous avons abordé cet aspect, il s’est avéré que le coût de la THA au niveau des ménages équivaut à un mois de leur revenu et que la THA fait perdre 2145 DALYs dans la communauté. L’intervention par la stratégie de dépistage-traitement a permis de sauver 1408 DALYs à un coût de 17 US$ par DALYs sauvé. Ce coût classe l’intervention comme « good value for money ».<p>Le recours au CATT seul s’est avéré comme la stratégie la plus efficiente pour le dépistage actif. Le gain marginal lorsque l’on ajoute la palpation ganglionnaire en parallèle est minime et n’est pas compensé par le coût élevé lié à un nombre important des suspects soumis aux tests parasitologiques. Les techniques de concentration ont une bonne sensibilité et leur faisabilité est acceptable. Leur ajout à l’arbre classique améliore la sensibilité de 29 % pour la CTC et de 42% pour la mAECT. Le coût de la CTC a été de 0,76 € et celui de la mAECT de 2,82 €. Le SF a été estimé très peu sensible. L’algorithme PG- GE-CTC-mAECT a été le plus efficient avec 277 € par vie sauvée et un ratio de coût-efficacité marginal de 125 € par unité de vie supplémentaire sauvée. L’algorithme PG-GE-CATT titration avec traitement des personnes avec une parasitologie négative mais un CATT positif à un seuil de 1/8 devient compétitif lorsque la prévalence de la THA est élevée.<p>Il est donc possible dans le contexte actuel de réduire la prévalence de la THA mais à condition que les activités ne soient pas interrompues. Le recours à un algorithme recourant au CATT dans le dépistage actif et à la séquence PG-GE-CTC-mAECT est le plus efficient et une efficacité de 80%. La faisabilité et l’efficacité peut être différent d’un endroit à l’autre à cause de la focalisation de la THA. Il est donc nécessaire de réévaluer cet algorithme dans un autre foyer de THA en étude pilote avant de décider d’un changement de politique. Le recours à cet algorithme implique un financement supplémentaire et une volonté politique. <p><p><p>SUMMARY<p>Human African Trypanosomiasis (HAT) remains a major public health problem affecting several countries in sub-Saharan Africa. HAT control is essentially based on active case finding conducted by specialized mobile teams. In the past the population screening was based on neck gland palpation, but since the development of the Card Agglutination Test for Trypanosomiasis (CATT) three control options are available to the control program: i) neck gland palpation ii) CATT iii) neck gland palpation and CATT done in parallel .Certain programs such as the one in DRC opted for the latter, combining CATT and neck gland palpation. All persons having hypertrophy of the neck gland and/or a positive CATT test are considered to be a HAT suspect. Confirmation tests are necessary because the screening algorithms are not 100 % specific and HAT drugs are very toxic. The classic parasitological confirmation tests are lymph node puncture (LNP), fresh blood examination (FBE) and thick blood film (TBF). The sensitivity of this combination is considered insufficient by several authors and causes important losses of efficacy of the screening-treatment strategy. More sensitive concentration methods were developed such as the mini Anion Exchange Concentration Techniques (mAECT), Capillary Tube Centrifugation (CTC) and the Quantitative Buffy Coat (QBC), but they are not used on a routine basis. Main reasons put forward are low feasibility, high cost and long time of execution. <p>In the Democratic Republic of Congo, HAT control activities were suddenly interrupted in 1990 and this led to an important re-emergence or the epidemic. Since 1998 onwards, control activities were financed again in a structured way.<p>This works aims to be both a plea for the continuation of HAT control as well as a contribution to the rationalization of the control strategies. We analyzed the evolution of sleeping sickness in the light of its financing, and we studied its impact on the household and the community. We aimed at a rationalization of the use of the screening and confirmation tools. We first evaluated the validity of the tests, their feasibility and the cost and we did a formal decision analysis to compare screening and confirmation algorithms. <p>The budget allocated to control activities was doubled during the period when structural aid funding was again granted (1998-2003) compared with the period before (1993-1997). The number of persons examined per year doubled as well but the number of cases found peaked at 26 000 in 1998 and dropped to 11 000 in the period afterwards. The cost per person examined was 1.5 US$ and per case detected and saved was 300 US$. The activities were financed for 95 % by external donors during this period. This subvention could give the impression that the impact of HAT on the household and the household was limited but when we took a closer look at this aspect we found that the cost at household level amounted to one month of income and that HAT caused the loss of 2145 DALYs in the community. The intervention consisting of active case finding and treatment allowed to save 1408 DALY’s at a cost of 17 US$ per DALY, putting the intervention in the class of “good value for money”. <p>The use of CATT alone as screening test emerged as the most efficient strategy for active case finding. The marginal gain when neck gland palpation is added is minor and is not compensated by the high cost of doing the parasitological confirmation test on a high number of suspected cases. The concentration methods have a good sensitivity and acceptable feasibility. Adding them to the classical tree improves its sensitivity with 29 % for CTC and with 42 % for mAECT. The cost of CTC was 0.76 US$ and of mAECT was 2.82 US$. Sensitivity of fresh blood examination was poor. The algorithm LNP-TBF-CTC-mAECT was the most efficient costing 277 Euro per life saved and a marginal cost effectiveness ratio of 125 Euro per supplementary life saved. The algorithm LNP-TBF-CATT titration with treatment of persons with a negative parasitology but a CATT positive at a dilution of 1/8 and more becomes competitive when HAT prevalence is high. <p>We conclude that it is possible in the current RDC context to reduce HAT prevalence on condition that control activities are not interrupted. Using an algorithm that includes CATT in active case finding and the combination LNP-TBF-CTC-mAECT is the most efficient with an efficacy of 80 %. Feasibility and efficacy may differ from one place to another because HAT is very focalized, so it is necessary to test this novel algorithm in another HAT focus on a pilot basis, before deciding on a policy change. Implementation of this algorithm will require additional financial resources and political commitment.<p><p> / Doctorat en Sciences de la santé publique / info:eu-repo/semantics/nonPublished

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