Aurore Bleuzen

Élastographie ultrasonore des lésionsthyroïdiennes

Elastosonography of thyroid lesions While ultrasound is theimaging modality of choice for diagnosis of thyroid lesions, characterizationremains limited and tissue diagnosis frequently is required for management. Theavailability of additional tools such as elastography may improve lesioncharacterization and direct management. Materials and Methods: Atotal of 96 patients (11 males and 85 females ;58±24 years) referred for fine needle aspiration (FNA) of mainlysolid thyroid nodules 9-32 mm in diameter underwent conventional US andelastosonography. Results on elastography were correlated with histologicalresults from FNA and classified as follows: suspected malignant lesion,suspected benign lesion, suspicious, indeterminate. Results: Thenodules were classified as follows: 95 nodules were soft (classes Iand II) and 13 nodules were hard (classes III and IV). No cancerswere detected in class and II lesions and 6 cancers were detected inclass III and IV lesions. FNA provided insufficient cellular material fordiagnosis in 5 class I-II nodules and 2 class III-IV nodules. Conclusion: Real-time elastosonography may be a useful adjunt toconventional US in the evaluation and characterization of thyroid nodulesallowing identification of patients at high risk of malignancy for whom tissuediagnosis and/or close follow-up is required.

Échographie de contraste temps réel dans la prise en charge diagnostique des lésions nodulaires hépatiques : évaluation des performances diagnostiques et de l'impact économique sur une étude multicentrique française

The recent introduction of high-end ultrasound equipment combined with recent contrast agents provides marked improvements in the characterization of focal liver lesions as previously reported by monocentric studies. The aim of the present study was to evaluate the diagnostic performance of Contrast-Enhanced Ultrasonography (CEUS) using SonoVue as well as its medico-economic value for characterization of focal liver lesions. These nodules were not characterized on previous CT or conventional sonography. This prospective multicentric study conducted in 15 French centres found diagnostic performances similar to those reported for CT and MRI, with a concordance rate of 84.5%, sensitivity greater than 80% and specificity greater than 90% for all types of lesions. Higher acceptance was found for CEUS compared to other imaging modalities. Economical assessment based on examination reimbursment and contrast agent cost showed a lower cost for contrast ultrasound versus CT and MRI. This French multicentric study confirmed the high diagnostic value of CEUS for focal liver lesion characterization and demonstrated a lower economical impact compared to other imaging modalities such as CT and MRI.

Differential diagnosis of focal nodular hyperplasia with quantitative parametric analysis in contrast-enhanced sonography.

Objectives:We investigated the potential of quantitative parametric analysis in the differential diagnosis of focal nodular hyperplasia (FNH) from other hypervascularized liver focal lesions. Materials and Methods:Eighty-five focal liver lesions (in 83 patients) were explored using contrast-enhanced ultrasound (SonoVue and Cadence Contrast Pulse Sequencing) consisting of typical FNH (n = 52), hepatocellular carcinoma (n = 11), hemangioma with high flow (n = 8), hypervascular metastases (n = 10), and hepatocellular adenoma (n = 4). QontraXt software (AMID, Italy) was used here to estimate the following parameters: maximum peak value, Tr (time corresponding to time for obtaining 63% of the plateau), β parameter corresponding to the exponential factor, and slope corresponding to the tangent value of the first phase of enhancement. These parameters were obtained from the time-intensity curves derived from the enhancement observed in 2 regions of interest corresponding, respectively, to the whole lesion and the central region only. Results:A significant statistical difference (P < 0.05) was found in the values of Tr, β, and slope between FNH and other hypervascularized lesions on both the whole lesion and central region. Among these parameters, slope appeared as the most valuable whatever the region of interest, ie, central or whole lesion (P < 0.01). Central region was more accurate in the differentiation of FNH and concordant with visual characterization. Conclusion:Quantitative parametric curve analysis of the different hypervascularized lesions confirms the depiction of the central artery in FNH and thus could help in differentiating this specific focal liver lesion from the others.

Preoperative Diagnosis of Ovarian Tumors Using Pelvic Contrast-Enhanced Sonography

Objective. The purpose of this study was to assess the feasibility of using a contrast agent for the sonographic examination of adnexal tumors and identify discriminating parameters in the preoperative diagnosis of malignant tumors. Methods. We conducted a prospective descriptive monocenter study that analyzed validated echographic criteria and parameters of the enhancement curve obtained by sonographic contrast agent injection. Patients included were referred for a second opinion after the discovery of a suspicious ovarian image. The final diagnosis was reached after surgery and an anatomopathologic examination. Results. Fifty‐two tumors were analyzed. Morphologic and Doppler criteria analyses were conducted as described in the literature. The significant parameters of the enhancement curve were the time‐intensity curve total area and the duration of activity of the contrast agent during the first phase of decay (P < .002). The performance of the contrast agent was lower than that of the examiners subjective diagnosis, with an area under the receiver operating characteristic curve (AUC) of 0.78 versus 0.80. When borderline tumors were eliminated, there was an inversion of this, with an AUC of 0.85 versus 0.73. The inclusion of contrast results in the examiners diagnosis in the context of a bivariate model comparing malignant and borderline tumors with benign tumors provided an AUC of 0.88. Conclusions. Contrast‐enhanced sonography improves preoperative diagnosis of ovarian tumors parameters. The significant parameters of the enhancement curve were significantly different for malignant and benign tumors. Borderline tumors contribute to a reduction of the discriminating capacity of the contrast agent.

Échographie de contraste dans l'exploration des lésions focales hépatiques: valeur diagnostique et recommandations

Resume La mise a disposition d’appareils d’echographie de haut niveau et de produits de contraste ultrasonore vient profondement modifier la prise en charge diagnostique des lesions hepatiques en apportant des elements caracteristiques reconnus et valides. L’imagerie non lineaire a bas index mecanique (MI L’interpretation de l’examen repose sur la presence de contraste intralesionnel (hyper, iso ou hyposignal) et le delai par rapport a l’injection (phase arterielle, portale ou parenchymateuse) selon une terminologie classique avec les methodes d’imagerie non ultrasonores autorisant une differenciation aisee lesions benignes et malignes, mais egalement une caracterisation complete comprise entre 85 et 95 % des cas pour l’ensemble des lesions focales hors hepatocarcinomes pour lesquels la fiabilite est voisine de 75 %. Ces resultats permettent de placer les methodes ultrasonores parmi les methodes de choix d’exploration non invasives des affections hepatiques nous amenant en consequence a modifier nos arbres decisionnels selon les types de lesions et la place actuelle de l’echographie. Il apparait ainsi la necessite de recourir a cette methode dans les bilans de neoplasie afin de pouvoir assurer une detection optimale des lesions secondaires hepatiques, mais egalement lors de la decouverte d’une lesion hepatique pour en assurer la caracterisation tout en diminuant les couts de prise en charge.

Penetration Depth with the XPS GreenLight Laser Assessed by Contrast Enhanced Ultrasonography

PURPOSE The GreenLight laser is one of the main alternative treatments for benign prostatic hyperplasia (BPH). Ultrasonography with contrast (ECUS) is one of the main innovations in radiology that has led to the examination of tissue vascularity. The objective of the study was to measure the impact of photovaporization of the prostate (PVP) on the prostate gland with ECUS. PATIENTS AND METHODS We conducted a pilot study to assess the impact of PVP on the prostate by using ECUS intraoperatively (ethical committee approval No. 2012-001451-39). Twelve patients undergoing PVP for symptomatic BPH were enrolled in this study after providing their informed consent. ECUS was performed just before and after PVP in the operating room and at 1 month postoperatively. RESULTS Comparative analysis showed that after PVP, a nonvascularized area with an average thickness of 11.1 mm was observed beyond the operative cavity. The nonvascularized area was thinner at 1 month postoperatively and disappeared at 6 months for the six patients evaluated. This is the first study using contrast-enhanced ultrasonography to measure the impact of PVP on the prostate. Our study has the limitations of a pilot study with a small population and a short follow-up. Based on these results, we would advise beginners to take into account the necrosis thickness and to limit the depth of vaporization. CONCLUSIONS Through the use of ECUS, our study demonstrated that a large area of necrosis is induced around the surgical cavity from the action of the GreenLight laser. Being aware of this phenomenon will certainly reduce the risk of complications induced by surgery.

Évaluation de l’apport de l’échographie de contraste dans l’analyse des kystes rénaux de nature indéterminée au scanner

PURPOSE To demonstrate the value of contrast-enhanced ultrasound (CEUS) in the management of Bosniak type 2F and 3 renal cysts on CT. PATIENTS AND METHODS Retrospective study of 14 patients with 15 Bosniak type 2F and 3 renal cysts on contrast enhanced CT. All patients underwent CEUS of the kidneys after injection of SonoVue(®). Using predetermined criteria, the lesions were classified as benign, malignant or indeterminate. Patients either underwent surgery or follow-up CT at one to three years. RESULTS From the 15 indeterminate cysts on CT, 12 were either benign (n=8) or malignant (n=4) on CEUS. From the eight cysts considered benign on CEUS, seven remained stable on follow-up CT after a minimum of one year interval and one was surgically resected and confirmed to be benign. All four cysts considered malignant on CEUS were surgically resected and three were confirmed to be malignant and one was confirmed to be benign. Three cysts were indeterminate: two lesions were surgically resected and one was benign while the other was malignant and one lesion was stable at one year follow-up CT. CONCLUSION CEUS was able to characterize indeterminate lesions as benign or malignant in 80% of cases with 92% reliability. Twenty percent of cysts remained indeterminate on CEUS. CEUS is reliable as a complement to CT in the evaluation of Bosniak type 2F and 3 renal cysts.

Adaptive AR and Neurofuzzy Approaches: Access to Cerebral Particle Signatures

In recent years, a relationship has been suggested between the occurrence of cerebral embolism and stroke. Ultrasound has therefore become essential in the detection of emboli when monitoring cerebral vascular disorders and forms part of ultrasound brain-imaging techniques. Such detection is based on investigating the middle cerebral artery using a TransCranial Doppler (TCD) system, and analyzing the Doppler signal of the embolism. Most of the emboli detected in practical experiments are large emboli because their signatures are easy to recognize in the TCD signal. However, detection of small emboli remains a challenge. Various approaches have been proposed to solve the problem, ranging from the exclusive use of expert human knowledge to automated collection of signal parameters. Many studies have recently been performed using time-frequency distributions and classical parameter modeling for automatic detection of emboli. It has been shown that autoregressive (AR) modeling associated with an abrupt change detection technique is one of the best methods for detection of microemboli. One alternative to this is a technique based on taking expert knowledge into account. This paper aims to unite these two approaches using AR modeling and expert knowledge through a neurofuzzy approach. The originality of this approach lies in combining these two techniques and then proposing a parameter referred to as score ranging from 0 to 1. Unlike classical techniques, this score is not only a measure of confidence of detection but also a tool enabling the final detection of the presence or absence of microemboli to be performed by the practitioner. Finally, this paper provides performance evaluation and comparison with an automated technique, i.e., AR modeling used in vitro

Apport de l'échographie de contraste et échographie conventionnelle simultanée en pathologie hépatique

Resume Objectifs Evaluation des possibilites de caracterisation des lesions focales du foie par superposition de l’imagerie echographique conventionnelle et de celle obtenue avec agent de contraste ultrasonore. Materiels et methodes L’imagerie simultanee du foie en niveaux de gris et avec l’agent de contraste a ete realisee chez 90 patients apres injection de Levovist ® (Schering, Berlin, Allemagne) en ayant recours a la methode « Agent Detection Imaging » (ADI, Siemens-Acuson, Mountain View, USA). Le balayage echographique du foie etait realise au moins 4 minutes apres l’injection de l’agent de contraste avec relecture des acquisitions en niveau de gris et en contraste. Les resultats en terme de detection et caracterisation de lesions ont ete compares a l“examen de reference retenu CT-scan ou IRM. Resultats Le diagnostic final etait : 20 examens normaux, 41 patients avec metastases, 6 patients porteur d’hepatocarcinome, 13 patients avec hemangiome, 6 avec lesions benignes autres et 4 avec kystes alors que pour 6 patients coexistaient des lesions de nature differente. L’echographie de contraste en phase tardive permettait le diagnostic lesionnel pour tous ces patients sauf pour un cas de metastase et les hepatocarcinomes. Dans le cas des hepatocarcinomes, si le caractere malin etait certain le diagnostic d’hepatocarcinome ne pouvait etre affirme. Pour 7 patients porteurs de lesions secondaires, il etait retrouve plus de lesions en ADI (4,9 lesions) qu’en echographie conventionnelle (1,1 lesion) alors que pour 3 patients, le scanner mettait en evidence plus de lesions que l’echographie de contraste (3,3 versus 1,6 lesions). En ce qui concerne la differenciation lesions benigne et maligne, la precision diagnostique atteignait 98,7 % avec Levovist ® quand elle n’etait que de 49,6 % en echographie conventionnelle (p Conclusion L’echographie de contraste avec superposition de l’imagerie bidimensionnelle permet d’ameliorer de facon sensible la performance diagnostique de l’echographie tant en terme de detection de lesions que de caracterisation.

Développements récents en imagerie ultrasonore de contraste à visée oncologique

Resume La combinaison appareils d’echographie de haut niveau et produits de contraste ultrasonore apporte des elements essentiels a la caracterisation des lesions et leur suivi sous traitement adapte, en particulier dans le domaine oncologique. Les resultats initiaux rapportes dans les differents travaux publies concernant la pathologie hepatique ont permis l’integration de cette methode parmi les methodes de reference ceci etant largement conforte par l’etablissement de recommandations europeennes. De nouvelles applications se sont fait jour au cours des dernieres annees et concernent l’ensemble de la pathologie oncologique accessible par ultrasons avec des apports diagnostiques varies selon les organes cibles. Le domaine plus specifique du suivi sous traitement physique ou cible est devenu un domaine de choix pour l’echographie de contraste avec des implications majeures en termes de validation de concepts, de prise en charge des patients par une evaluation plus fiable et plus rapide des effets therapeutiques. C’est l’objet de cette revue que de presenter les avancees recentes dans les domaines ci-dessus avec pour objectif de mieux cerner la place des ultrasons modernes en pathologie oncologique.