Apport de l’imagerie radioisotopique dans l’artérite inflammatoire des gros vaisseaux

The group of large vessel vasculitis includes giant cell arthritis and Takayasu's disease. If monophotonic nuclear medicine can sometimes show some unusual patterns in these diseases, positron emission tomography with fluorodeoxyglucose seems have a special attract and provide some indications during the monitoring of these patients. However, most of these indications remain to be validated, specially to differentiate weak vascular wall inflammatory activities from physiological and/or atherosclerotic accumulation.     

L’éclairage biologique des activités mentales: réduction ou mise en perspective ?

The relationship between the human psychological faculties and their underlying biological foundation is traditionally addressed within the mind-matter philosophical framework and its ethical extension regarding freedom and determinism. Neurobiology represents a new method, reflective of our times, to articulate the relationships between biological and psychological phenomena. The various points of view in this field are often based on implicit ontological presuppositions and, at least sometimes, unconscious epistemological assumptions: monism vs dualism, functionalism, reductionism, eliminativism, type identity and other more or less sophisticated variations. Bearing in mind the pitfalls these create, we can try to determine structural analogies across the different levels of the living being and the mind: the energy imbalance maintained for cell survival; the dynamic and complementary relationship between homeostatic and allostatic functions in living organisms; the tension between essential and complementary cognitive brain processes, such as the processes used to represent an object and those used to locate an object in space. Those phenomena all bear structural analogies, even though they work at different levels.     

Etude des troubles psychiatriques et des mécanismes de défense psychologiques dans une population d’hommes stériles consultant en Andrologie

Results

26.2% of this population presented psychiatric disorders according to DSM-IV with a significant over-representation of generalized anxiety disorder and somatization disorder. The comparison between azoospermic males and oligoazoospermic males demonstrate the absence of significant difference in terms of psychiatric morbidity rate and use of defense styles. This population used similar defense modalities to the general population and preferentially used defense mechanisms corresponding to the mature defense style, such as humor, repression and anticipation. Psychiatric illness was significantly correlated with preferential use of withdrawal, consumption, reaction formation and lack of humor. This study also confirmed that subjects who essentially using neurotic defense styles were more likely to develop psychiatric disorders.

Conclusion

No difference in psychological effects was observed according to the degree of sterility. On the other hand, the presence of an over-representation of psychiatric disorders in sterile males compared to a control group indicates that Consultation-Liaison psychiatrists and andrologists must try to understand the patient’s suffering beyond the need for artificial insemination. Patients should therefore be given an opportunity to express all of the feelings related to their personal and marital drama in the department in which they are treated, as part of specialized management. Our study confirms the difficulty of determining whether certain defense mechanisms constitute risk factors for psychiatric disorders or whether defense mechanisms are an epiphenomenon of a particular psychiatric disorder, which is why many authors using DSQ agree that additional prospective studies are necessary to investigate correlations between defense mechanisms and specific psychiatric disorders. It would be useful to investigate defensive modalities before the diagnosis of infertility and after birth of a child in a larger population. A better understanding of the defensive modalities used by this type of population, in a psychotherapeutic context, could help to prevent or at least predict the appearance of psychiatric disorders.     

Pièges et artéfacts en imagerie TEP/TDM : intérêts des post-traitements

In PET imaging, quantification of the acquired data can be achieved by using a series of correction techniques to minimize the effects inherent in the imaging process of emission tomography. Quantitative images can be reconstructed after correcting the detected emission data for the presence of random and scattered coincidences, attenuation effects, effects associated with the variable detectors sensitivity, effects related to the geometry of the device and the effects of dead-time. All these effects are well accounted for in the PET imaging market. However, other effects can degrade the quality of the PET images, such as the finite spatial resolution generating partial volume effects, or the patient movements including respiratory and cardiac physiological movements. In the thoracic field, the effects of respiratory motion on PET images are characterized by a loss of detection sensitivity due to the associated blur. Several methods have been developed to correct for these effects, but still without a wide acceptance in clinical routine. These research areas are therefore still very active.     

Impact d’une réduction d’activité sur la mesure de la fraction d’éjection du ventricule gauche sur caméra D-SPECT

IntroductionRadionuclide ventriculography provides a reproducible measurement of the left ventricular fraction ejection (LVEF) but with a significant body radiation (effective dose of 5,9 mSv for the injection of 850 Mbq of ^99mTc). The highly sensitive semi-conductor (CZT) cameras could allow decreasing the injected activity by a factor 3, similarly to that of myocardial perfusion imaging. Our study was aimed to determine whether the LVEF measurement provided by radionuclide ventriculography on the CZT D-SPECT camera is impacted by a 70% reduction in recorded counts.Materials and methodsAfter the in vivo labeling of red blood cells with 850 MBq of ^99mTc, 49 patients completed a conventional 2D recording (Conv-2D) on Anger camera followed by a 3D recording on the D-SPECT camera (3D-100%). The CZT recordings of all projections were subsequently shortened to 30% of their initial durations (3D-30%) in order to assess the LVEF measured with a 70% reduction in recorded counts.ResultsMean LVEF values were 62.7 ± 11.1% on Conv-2D and higher on both 3D-100% (66.8 ± 14.8%, P < 0.001) and 3D-30% (66.3 ± 15.7%, P < 0.001). The correlation coefficients with the LVEF determined with the reference Conv-2D method were equivalents for 3D-100% (r² = 0.73) and 3D-30% (r² = 0.70) and with a similar level of overestimation for the highest LEVF values.ConclusionA 70% reduction in recorded counts does not significantly impact the LVEF measured with radionuclide ventriculography on the CZT D-SPECT camera. These values are coherent with those obtained with the reference 2D method but with a clear overestimation for the highest LVEF values.     

Les méthodes de seuillage en TEP : un état de l’art

This work deals with positron emission tomography segmentation methods for tumor volume determination. We propose a state of art techniques based on fixed or adaptive threshold. Methods found in literature are analysed with an objective point of view on their methodology, advantages and limitations. Finally, a comparative study is presented.     

Mise en place humaine des systèmes d’information en cancérologie : mesure du degré d’applicabilité des moyens et de désordre (entropie)

ObjectivesWe conducted a human model to score the initial expectations (E1), the final realization (E2) and the means involved (E3) in developing an information system (IS) in oncology.MethodsOur field study is carried out using questionnaires (Q1, Q2 and Q3) based on a model built using four universal ethical principles: autonomy–beneficence–non-maleficence–justice we meet with environmental parameters of reality. We interviewed 14 designers of IS who have respectively set up their IS in a facility that supports cancer in the Bouches-du-Rhône. From scores of E1, E2 and E3, a degree of disorder (entropy: S) for an IS is measured.ResultsRegardless of the nature of the IS, the score E1 is always higher than E2. The score E3 is considered insufficient except in the mass screening of breast cancer. Finally, the degree of applicability of the means (M) used is correlated with the S existing within the IS.DiscussionWith over 14 participants, this study can have only qualitative value due to reduced statistical power too. Should expand the number of respondents to increase the effective intrinsic power of the analysis and thus reinforce the trend of our results.ConclusionEthical behavior shown by the means used would decrease the entropy as the information more meaningful, while an increase of entropy would be harmful.     

Intégration des Facteurs Humains dans les démarches de conception et d’implémentation des NTIC en Santé

This paper addresses the question of Human Factors/Ergonomics approach to ensure a safe and effective design and implementation of Health Information Technologies in healthcare environments. It provides an overview of the domain and presents an illustration of the integration of the Human Factors principles and methods in the design cycle of an analgesia monitor.