Intérêt de l’imagerie hybride TEMP-TDM dans l’exploration des infections

Single-Photon Emission Computed Tomography-Computerized Tomography (SPECT-CT) is a new hybrid technique which offers new diagnostical capabilities in daily nuclear medicine practice. This technique not only allows to acquire fusioned anatomic and functional images in the same time, but also, it increases sensitivity and accuracy of SPECT thanks to attenuation and scattering corrections got from transmission data. Until now, SPECT-CT data have been mainly obtained in oncology and cardiology, but now, many authors use it in many scan studies and particularly for infectious diseases. In inflammatory bowel diseases, SPECT-CT seems to increase diagnostical performances and to modify management of many patients. In suspected vascular sepsis, SPECT-CT could increase sensitivity of white blood cell scintigraphy but also its specificity thanks to spatial resolution of CT. In osteoarticular sepsis, SPECT-CT has the advantage to distinguish osteomyelitis from soft tissue infection and to guide biopsies. Nevertheless, in the light of PET-CT works, SPECT-CT development will probably modify nuclear medicine practice and many studies have to be conducted to highlight consensual procedure guidelines.     

Intérêt de la TEP dans le bilan d’extension et l’évaluation de la maladie résiduelle des séminomes testiculaires : étude rétrospective

AimsTo evaluate the value of PET/CT comparatively to CT in staging and restaging after chemotherapy of testicular seminoma, to assess quantitative methods and prognostic value of PET in post-chemotherapy residual masses.MethodsThirty-two patients and a maximum of 65 targeted lesions visualized on PET-CT and CT performed for staging and therapeutic response assessment were analysed and compared. Each lesion was quantified according to miscellaneous SUV normalized methods. Optimal threshold of SUV for prediction of residual disease was obtained (ROC method). The prognostic value of PET/CT at the completion of treatment was determined with progression free survival study (Kaplan-Meier method).ResultsPET/CT exhibited higher accuracy than CT in the initial staging and assessment of therapeutic response, respectively 98% versus 83.3% and 95.1% versus 75.6%. Quantification, whichever method, was not more efficient than visual reading for prediction of residual disease. Progression-free survival was higher with negative than with positive PET/CT (P = 0.0033).ConclusionOur work demonstrates that PET/CT exhibits better accuracy than CT in both staging and restaging at the end of treatment. Quantification methods do not improve accuracy of PET/CT for prediction of viable residual disease. The prognostic value of PET/CT appears very promising and needs to be confirmed by large prospective studies. PET/CT appears to be a relevant method of prognostic stratification of the risk of relapse in seminoma.     

Intérêt de la spectrométrie de masse de type MALDI-TOF pour l’identification des champignons filamenteux

Identification of filamentous fungi, molds and dermatophytes, is currently based on the morphological study of colonies and therefore the experience of the mycologist. These techniques are not sufficiently precise to distinguish between different species within the same section. Furthermore, identification can be delayed for several weeks due to subcultures on specific media. MALDI-TOF MS allows correct identification of filamentous fungi until the species level in more than 95% of cases in most studies. MALDI-TOF MS is a fast and precise identification technique for filamentous fungi; however most of the different databases need to be further evaluated in routine and completed to broaden the spectrum of species identified.     

Intérêt du dosage de l’inhibine B et de l’AMH dans le plasma séminal: étude préliminaire

Objectives

The aim of this study was to establish reference values for seminal inhibin B and AMH concentrations in patients with normal and abnormal sperm parameters. Preliminary analysis was performed to evaluate the predictive value of these markers for retrieving testicular sperm in non-obstructive azoospermic men.

Methods

Seminal inhibin B and AMH concentrations were assayed by an enzyme-linked immunoassay in three groups of men: 47 patients with normal sperm parameters, 28 oligospermic men and 68 patients with azoospermia.

Results

Inhibin B and AMH concentrations varied considerably in the three groups, but were significantly higher in normospermic men (inhibin B: 714.36±522.66 ng/l, AMH: 97.08±135.15 pmol/l) than in oligospermic men (inhibin B: 417.5±386.9 ng/l, AMH: 62.02±93.33 pmol/l) and azoospermic men (59.61±2.65 ng/l et 13.12±31.94 pmol/l, respectively) (p<0.001). A significant correlation (p=0.0054) was observed between seminal inhibin B concentration and sperm production. Testicular biopsy allowed sperm retrieval in 11 out of 21 patients (52.3%). The predictive value of seminal inhibin B was analyzed using receiver operating characteristics (ROC) curve analysis. The best discriminating inhibin B concentration was 30 ng/l with an area under the curve (AUC) of 0.63.

Conclusion

This study confirms the correlation between seminal inhibin B and AMH concentrations and spermatogenesis. However, the significance of these two markers as predictors of the presence of testicular sperm in men with non-obstructive azoospermia is limited. This analysis shows that AMH and inhibin B, either alone or in combination with serum FSH, fail to predict the presence of sperm in men with non-obstructive azoospermia undergoing testicular sperm extraction.     

Personnages dans l’art saharien : le réel et l’imaginé

In the Sahara, wherever there are naked rock surfaces, engravings and paintings have been found in large numbers. This rock art includes various types of images — the oldest dating about ten millenniums — among which human beings, wild or domesticated animals, therianthrops and non-explicit images can be identified. According to periods and styles, the human being has been represented under extremely varied aspects from particularly realistic — similar to the reality — till very simplified, even caricatural drawings. For some realistic representations of women and men, we can observe anatomical or morphological peculiarities which, without being frequent, show cases of steatopygy and gynoïd or androïd obesity, pathological or not. For certain periods, we also find imaginary, fantastic or caricatural representations. These images characterize particularly styles previous to that called “Round Heads”. So, in the Saharan art, the human being has been represented either in his physical truth, or according to multiple stylistic conventions or graphic stereotypes, which could characterize certain ethnic groups.     

Intérêt de l’utilisation de la scintigraphie osseuse dans le diagnostic et le suivi de l’ostéochondrite primitive de la hanche

Osteochondritis, or Legg-Calvé-Perthes disease (LCP), is a necrosis of the proximal femoral epiphysis. This vascular accident entails on the complex phenomenon of growth of the child's hip and can result in deformations or even a strict destruction of the proximal femoral epiphysis. The aim of this article is to show the interest of the bone scintigraphy (BS) in precocious diagnosis and follow-up of LCP disease. In this aim, we introduced a clinical case of LCP disease where BS allowed a precocious diagnosis and a strigent monitoring. Discussion of case includes a systematic review of literature.     

L’erection et l’ejaculation psychogenes: Mythe ou realite? Intérêt de leur recherche chez le blessé médullaire

Erection and ejaculation can be induced by two forms of stimulation. The first is mechanical: touching of the penis, scrotum and anus stimulates the pudendal nerves and a reflex erection appears via the parasympathetic pathway. The second form of sexual stimulation is psychological: erotic pictures and fantasies stimulate the splanchnic nerves and the hypogastric plexus, via the orthosympathetic dorso-lumbar pathway, and induce a psychogenic erection. Spinal injury can destroy a part of these neurological routes and cause impotence and/or failures of ejaculation. We have studied 35 patients reporting a sexual dysfunction after a spinal injury, and have tried to generate an erection and ejaculation first with mechanical stimulation, and then with erotic pictures without mechanical genital stimulation. Tumescence was registered using a plethysmograph and semen was collected in order to study spermatogenesis. The spinal cord was destroyed in 12 patients, but orthosympathetic stimulation produced a psychogenic erection in 15 cases, followed by ejaculation in six cases. This form of stimulation seems to be better than prostaglandin or electrical stimulation.     

Intérêt de l’imagerie hybride TEMP/TDM pour la scintigraphie des récepteurs de la somatostatine dans le bilan des tumeurs endocrines gastro-entéro-pancréatiques

In this work, we have evaluated the potential of image fusion and attenuation correction (AC) of SPECT-CT imaging for the assessment of gastro-entero-pancreatic endocrine tumors by somatostatin receptor scintigraphy (SRS).MethodAfter optimisation of acquisition and reconstruction parameters, we have evaluated, in a prospective study, SRS performed over a period of one year. We have compared visual interpretations of planar and tomographic images versus SPECT/CT images to determine if anatomical localisation and diagnostic contributions are improved. In a semi-quantitative analysis of pathological foci, we have measured maximal intensity values (T_max), tumour to background ratios (T/B) and tumour contrasts (Ct) with and without AC.ResultsIn 25 SRS, visual analysis has shown anatomical localisation improvements in 60% of cases (CI95%, 39–79) and diagnostic improvements in 64% of cases (CI95%, 43–82). Doubtful foci proportion changed from 44 to 11%. In the semi-quantitative analysis of 41 pathological foci, Wilcoxon matched-pairs tests showed significantly higher T_max, T/B and Ct values after AC.ConclusionSPECT/CT imaging improves diagnostic quality of SRS thanks to a better foci localisation and a better lesional contrast in the image.     

Intérêt de l’imagerie hybride TEMP/TDM dans la localisation des glandes parathyroïdes ectopiques : à propos de 3 cas

The presence of a parathyroid gland in ectopic position constitutes one of the leading causes of surgery failure. For this purpose, scintigraphy takes a major place in the anatomical localization of pathological parathyroid and so facilitates its treatment. The advent of hybrid cameras combining single photon emission tomography to CT (SPECT/CT) has further strengthened the contribution of this imaging modality in the precise localization of ectopic parathyroid and its anatomical relationships. The objective of our work is to illustrate the interest of hybrid imaging SPECT/CT, compared to planar scintigraphy and ultrasounds within the framework of primary hyperparathyroidism, particularly ectopic situation through three cases.     

Intérêt complémentaire de la TEP/TDM au FDG et de l’imagerie conventionnelle dans le bilan initial et le suivi post-thérapeutique des cancers des VADS : recommandations et perspectives

Functional imaging by ¹⁸fluorodesoxyglucose (FDG) positron emission tomography (PET) and morphological imaging by computed tomography (CT) and magnetic resonance imaging (MRI) hold an important and complementary role in characterization of head and neck squamous cell carcinoma (HNSCC). Based on an exhaustive literature, the recommendations and perspectives of their use in the initial assessment and the post-therapeutic management of HNSCC are presented.     

Intérêt de l’analyse de la morphologie fine et de la qualité nucléaire des spermatozoïdes dans le cadre des techniques d’AMP

Routine semen examination does not identify minor malformations of the sperm nucleus and chromatin architectural defects, which may be associated with ART outcome and cannot be detected by the embryologist even at 1000x magnification. Recent publications have demonstrated the advantages, compared to routine analysis, of a new method of real-time detailed morphological evaluation of motile spermatozoa: motile sperm organellar morphology examination (MSOME). MSOME is performed with an inverted light microscope equipped with high-power differential interference contrast optics enhanced by digital imaging to achieve a magnification of 10000x. To be considered morphologically normal, a sperm nucleus must have both a normal shape and a normal chromatin content. The aim of the present study was to combine MSOME and sperm DNA fragmentation characteristics to assess reproductive outcome. The study population consisted of the male partners of 52 couples referred for conventional IVF or split cycles (half IVF-half ICSI cycles) and exhibiting normal routine sperm parameters. Spermatozoa were analysed by examining the fine nuclear morphology and DNA integrity using the sperm chromatin dispersion test (SCD test), based on the principle that the deproteinized nuclei of spermatozoa with nonfragmented DNA show extended halos of DNA dispersion that are either absent or only minimally present in sperm nuclei with fragmented DNA. Fertilization rates were significantly lower in the group showing less than 8% of normal spermatozoa according to MSOME criteria, but early embryo development was not affected. Fine sperm morphology correlated with DNA fragmentation rate. These results demonstrate that the assessment of sperm nuclear normality by MSOME analysis and SCD test improves characterization of the semen sample and should be evaluated as a tool for allocating patients to specific assisted reproduction treatments.     

Intérêt de la TEP-FDG dans le syndrome d’hyper-IgG4 : à propos d’un cas et revue de la littérature

Hyper-IgG4 syndrome, or IgG4-related systemic disease (IgG4-RSD), is a recently described entity of fibro-inflammatory systemic damage. Multiorgan lesions can occur synchronously or metachronously in a same patient. The common histological features include a lymphoplasmacytic infiltration (especially to IgG4), and fibrosis. Elevated serum level of IgG4 is also often present. The main concerned organs are: pancreas, biliary ducts, mediastinal lymph nodes, peritoneum, lacrimal and salivary glands. We report a case of an unusual location of this disease at the nasophyrnx in a patient of 84 years for which the diagnosis was made through immunolabelling with IgG4 in lesions biopsied, and we illustrate the potential role of PET-FDG in this systemic disease.