Scintigraphie de perfusion cérébrale positionnelle : résultats physiologiques et applications cliniques

To assess the impact of standing on brain perfusion, 125 brain perfusion scans in the upright and supine position were performed, including 108 patients. Perfusion values were compared using a relative quantitative approach and a segmentation of vascular territories with the help of an atlas of brain perfusion. We found a change in the distribution of the perfusion in favor of the vertebro-basilar system in the upright position. We discuss the case of a patient whose symptoms could be explained with the help of the comparison of brain perfusion scans in the upright and supine position. Atheromatous and post-dissection stenosis and their influence on perfusion are also discussed.     

Intérêt d’une semi-quantification et d’une analyse statistique automatique pour l’interprétation de la tomoscintigraphie cérébrale de perfusion dans la maladie d’Alzheimer

IntroductionAs the visual interpretation of the brain perfusion SPECT for the diagnosis of Alzheimer's disease might be difficult, it is wished to benefit from techniques allowing to improve the diagnostic accuracy especially for the inexperienced readers.Materials and methodsThree readers retrospectively interpreted 77 ^99mTc-ECD SPECT studies within the context of suspected neurodegenerative disease. The probability of Alzheimer's disease was quoted from 1 to 5, and the optimum sensitivity and specificity values were determined from ROC curves. The readers also attributed a hypoperfusion score to 13 brain regions; a diagnosis was obtained from this semi-quantification using a simple logic rule. The SPECT scans were also analyzed using the Planet Neuro software and a diagnosis was reached from a threshold for 2 of the 90 analyzed regions. The gold standard was established by a comprehensive neurological evaluation with at least 5 years of follow-up.ResultsThe sensitivities and specificities of the three readers were 50 %, 56 %, 28 % and 76 %, 83 % and 90 %, respectively. Using the semi-quantification they were 50 %, 67 %, 61 % and 54 %, 85 %, 69 %. The results of two readers were more in agreement. Using the automatic quantification, sensitivity was 78 % and specificity 81 %.ConclusionThe semi-quantification seems to ameliorate the results of and the agreement between certain readers. However, the automatic quantification seems to be the only way of assisting all of the readers to improve their diagnostic performances.     

Effets de l’âge et du genre sur la perfusion cérébrale régionale étudiée par deux méthodes d’analyse statistique voxel-par-voxel

Fully automated analysis programs have been applied more and more to aid for the reading of regional cerebral blood flow SPECT study. They are increasingly based on the comparison of the patient study with a normal database. In this study, we evaluate the ability of Three-Dimensional Stereotactic Surface Projection (3D-SSP) to isolate effects of age and gender in a previously studied normal population. The results were also compared with those obtained using Statistical Parametric Mapping (SPM99).MethodsEighty-nine ^99mTc-ECD-SPECT studies performed in carefully screened healthy volunteers (46 females, 43 males; age 20–81 years) were analysed using 3D-SSP. A multivariate analysis based on the general linear model was performed with regions as intrasubject factor, gender as intersubject factor and age as covariate.ResultsBoth age and gender had a significant interaction effect with regional tracer uptake. An age-related decline (p < 0.001) was found in the anterior cingulate gyrus, left frontal association cortex and left insula. Bilateral occipital association and left primary visual cortical uptake showed a significant relative increase with age (p < 0.001). Concerning the gender effect, women showed higher uptake (p < 0.01) in the parietal and right sensorimotor cortices. An age by gender interaction (p < 0.01) was only found in the left medial frontal cortex. The results were consistent with those obtained with SPM99.Conclusion3D-SSP analysis of normal rCBF variability is consistent with the literature and other automated voxel-based techniques, which highlight the effects of both age and gender.     

Scintigraphie myocardique et séquelles de myocardite : présentation d’un cas clinique

Acute and subacute myocarditis are well-defined pathological entities but it is often difficult to identify them because their clinical expression is variable and the diagnosis is histological showing myocardial inflammation associated with degeneration and/or necrosis. Often symptoms are similar to those of acute pericarditis with “chest-crushing” pain that mimics myocardial infarction and prompts practitioners to request angiography, especially when there are cardiovascular risk factors. We report the case of a 61-year-old patient with neither cardiac history nor cardiovascular risk factor who consulted for a long and self-limited atypical chest pain with normal clinical examination and electrocardiogram. Myocardial perfusion scintigraphy showed a non-reversible photopenic area suspected of being a nontransmural necrosis or an artifact. The discovery of inferolateral hypokinesis of left ventricle on echocardiography led to perform a coronary angiography which was finally normal. Cardiac MRI allowed to diagnose scars of a previous episode of myocarditis.     

Scintigraphie osseuse et déficit en IGF1 : présentation d’un cas clinique

Growth delay in adults with GH (growth hormone) or insulin-like growth factor 1 (IGF1) deficiency is often associated to low bone mineral density (BMD), osteoporosis and a higher risk of fractures (Tritos et al., 2011 [1]; Wüster et al., 2001 [2]; Bex et Bouillon, 2003 [3]). However to date, the risk of fractures in children with GH or IGF1 deficiency is not clearly evaluated (Högler and Shaw, 2010 [4]). This is the case of a young woman aged 21, with a syndrome including a severe mental, growth and weight retardation (–4 SD), facial dysmorphism and partial epilepsy, who recently presented walking and muscle strength loss, without history of trauma. Bone scan revealed several hot spots related to cortical bone fractures and biological data showed an IGF1 deficiency. Through this case, we discuss the role played by GH and IGF1 in bone growth, and the basic procedures to follow in children when measuring BMD with dual absorptiometry X ray technique (DXA).     

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.     

Délocalisation de la biologie d’urgence et Assurance Qualité

La biologie délocalisée prend une importance croissante dans le fonctionnement des services traitant les urgences à l’h?pital. Elle devrait représenter une réele évolution pour la prise en charge du patient tout en améliorant l’organisation interne des unités de soins. Le biologiste occupe un r?le clé pour mener un tel projet et la mise en place d’un système d’assurance qualité adapté à cette pratique est indispensable.     

Aspects réglementaires et organisationnels de l’activité d’autoconservation. Le point de vue du juriste

At the present time, legal texts in application of bioethics laws only briefly mention cryopreservation. The conditions of cryopreservation differ according to the type of tissue stored: while cryopreservation of oocytes and ovarian tissue corresponds to the field of biomedical research, semen cryopreservation corresponds to medically assisted procreation. Cryopreservation activity is more clearly defined in the draft revision of the bioethics law. Concerning the cryoconservation of ovarian tissue and oocytes, these difficulties result in particular in this activity’s mixed nature. It is located indeed, halfway between research and care. These two spheres of medical activity are subjected to their own distinct and exclusive, and their application is conditioned by the qualification of the implemented act. However, this qualification is dubious here, because of, in particular, the impossibility of determining which acts of sampling, cryoconservation and use might be concerned with a research protocol. Concerning the cryoconservation of sperm, the texts, first of all, seem to assimilate the activity of cryoconservation within an activity of assisted medical procreation. However, such assimilation would be equivalent to the impossibility of its implementation, because of the difficulty of respecting all of the legal conditions of assisted medical procreation. However, another more favourable interpretation of the provisions seems to be possible. Taking into consideration these uncertainties, contradictions and difficulties, the legislator intervened and devoted, by the widening of the indications of assisted medical procreation, the activity of cryoconservation in the project of revision of the laws of bioethics. He however did not solve all the difficulties. These cryoconserved elements can be restored only to the depositor. Indeed, the texts make obstacle to a delivery for a third party of the cryoconserved sperm, whatever the moment. They can also be used. This use can consist of assisted medical procreation, which is the first finality of cryoconservation — but it could only be implemented in respect of the whole of the legal conditions. It seems that the cryoconserved elements could also be used within the framework of research, whatever its nature (biomedical or not) and the moment of its implementation (while the person is alive or after his death). Its implementation should however be subjected to prior agreement and expressed while the person, whose elements were preserved, is alive. Such a use is expressly made possible in the project of revision of the laws of bioethics. Following a partial use or a lack of such a use, the destruction of the cryoconserved elements can be considered, as well as the continuation of the cryoconservation. However, these hypotheses raise difficulties that have not yet been resolved in the draft revision of the bioethics law.