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1.
Diagn Interv Imaging ; 101(10): 643-648, 2020 Oct.
Article de Anglais | MEDLINE | ID: mdl-32482584

RÉSUMÉ

PURPOSE: The purpose of this study was to evaluate the effectiveness of computed tomography (CT)-guided infiltration of greater occipital nerve (GON) for the treatment of refractory craniofacial pain syndromes other than occipital neuralgia. MATERIALS AND METHODS: Fifty-six patients suffering from refractory craniofacial pain syndromes were included between 2011 and 2017. There were 33 women and 23 men with a mean age of 50.7 years±13.1 (SD) (range: 27-74 years). CT-guided infiltration was performed at the intermediate site of the GON with local anesthetics and cortivazol. Twenty-six (26/56; 46%) patients suffered from chronic migraine, 14 (14/56; 25%) from trigeminal neuralgia and 16 (16/56; 29%) from cluster headaches. Clinical success at 1, 3, and 6 months was defined by a decrease of at least 50% of pain as assessed using visual analog scale (VAS). RESULTS: Mean overall VAS score before infiltration was 8.7±1.3 (SD) (range: 6 - 10). Mean overall VAS scores after infiltration were 2.3±3 (SD) (range: 0 - 10) (P<0.01) at one month, 3.5±3.3 (SD) (range: 0 - 10) (P<0.01) at three months and 7.6±1.3 (SD) (range: 1-10) (P<0.01) at six months. After infiltration, clinical success was achieved in 44 patients (44/56; 78.5%) at 1 month, 37 patients (37/56; 66%) at 3 months and 13 patients (13/56; 23%) at 6 months. Clinical success according to the clinical presentation were as follows: 88% (23/26) at one month, 73% (19/26) at 3 months, and 23% (6/26) at 6 months in patients with chronic migraine, 81% (13/16), 69% (11/16) and 31% (5/16) in those with cluster headaches and 57% (8/14), 50% (7/14) and 14% (2/14) in those with trigeminal neuralgia. No major complications due to CT-guided GON infiltration were reported in any patient. CONCLUSION: CT-guided infiltration at the intermediate site of the GON appears as an effective treatment of craniofacial pain syndromes especially in patients with chronic migraine and those with cluster headaches.


Sujet(s)
Névralgie faciale , Névralgie , Adulte , Sujet âgé , Anesthésiques locaux , Femelle , Humains , Mâle , Adulte d'âge moyen , Névralgie/traitement médicamenteux , Nerfs spinaux/imagerie diagnostique , Tomodensitométrie , Résultat thérapeutique
2.
Diagn Interv Imaging ; 99(4): 189-218, 2018 Apr.
Article de Anglais | MEDLINE | ID: mdl-29482969

RÉSUMÉ

Ultrasound and slice imaging are currently the key modalities for diagnosing simple renal cysts. Benign simple renal cysts are defined by a set of strict criteria. Any cystic lesions that do not meet these criteria should be classified as "atypical" or "complex" and considered as suspicious. For over three decades, the Bosniak classification has been the central tool for diagnosing renal cystic masses larger than 1 cm. The Bosniak classification is based upon the results of a well-established pre- and post-contrast computed tomography (CT) protocol. Lesions that are difficult to classify or that remain indeterminate after CT can benefit from a multimodal diagnostic approach combining CT, non-contrast-enhanced and contrast-enhanced ultrasound, and magnetic resonance imaging.


Sujet(s)
Maladies kystiques rénales/classification , Maladies kystiques rénales/imagerie diagnostique , Produits de contraste , Arbres de décision , Imagerie diagnostique/méthodes , Humains
3.
Eur Radiol ; 26(4): 1108-15, 2016 Apr.
Article de Anglais | MEDLINE | ID: mdl-26201293

RÉSUMÉ

UNLABELLED: Tubulocystic renal cell carcinoma (TC-RCC) is a recently identified renal malignancy. While approximately 100 cases of TC-RCC have been reported in the pathology literature, imaging features have not yet been clearly described. The purpose of this review is to describe the main radiologic features of this rare sub-type of RCC on ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI), based jointly on the literature and findings from a multi-institutional retrospective HIPAA-compliant review of pathology and imaging databases. Using a combination of sonographic and CT/MRI features, diagnosis of TC-RCC appeared to be strongly suggested in many cases. KEY POINTS: • Tubulocystic renal cell carcinoma is a new entity with typical imaging features • Diagnosis of tubulocystic renal cell carcinoma can be suggested preoperatively by imaging • Cystic renal lesions with high echogenicity may correspond to tubulocystic carcinoma.


Sujet(s)
Néphrocarcinome/diagnostic , Tumeurs du rein/diagnostic , Imagerie par résonance magnétique , Tomodensitométrie , Échographie , Adulte , Sujet âgé , Femelle , Humains , Rein/imagerie diagnostique , Rein/anatomopathologie , Mâle , Adulte d'âge moyen , Études rétrospectives
4.
Diagn Interv Imaging ; 96(4): 373-81, 2015 Apr.
Article de Anglais | MEDLINE | ID: mdl-25556292

RÉSUMÉ

OBJECTIVES: The goals of the study were to describe the MR imaging features of endometriosis of the urinary tract and identify those that suggest intrinsic involvement of ureteric wall. MATERIALS AND METHODS: Thirty-five women with proven urinary tract endometriosis and who had preoperative MR imaging between 2001 and 2011 were included retrospectively. MR images were intrepreted by one junior and one senior radiologists. To characterize the intrinsic parietal involvement, the ureteric circumference involved by the lesion of endometriosis was noted. RESULTS: Thirty-eight ureteric and 13 bladder lesions were analyzed. They were found in association in nine women. Ureteric lesions were bilateral in seven women. Of the 38 ureteric lesions, 27 were extrinsic and 11 intrinsic at histopathological analysis. Sixteen women with extrinsic lesions and 10 with intrinsic ones were correctly identified on MR imaging. When the ureter was included less than 360° in the lesion, extrinsic involvement was confirmed in 80% of cases. CONCLUSION: MR imaging appears to be more sensitive (91%vs 82%) but less specific (59% vs 67%) than surgery for the diagnosis of intrinsic form of ureteric location.


Sujet(s)
Endométriose/anatomopathologie , Endométriose/chirurgie , Imagerie par résonance magnétique , Maladies urétérales/anatomopathologie , Maladies urétérales/chirurgie , Maladies de la vessie/anatomopathologie , Maladies de la vessie/chirurgie , Adulte , Femelle , Humains , Adulte d'âge moyen , Études rétrospectives
5.
Eur J Radiol ; 84(3): 360-365, 2015 Mar.
Article de Anglais | MEDLINE | ID: mdl-25547327

RÉSUMÉ

OBJECTIVES: The purpose of this retrospective study was to evaluate the diagnostic performance of double-echo gradient chemical shift (GRE) magnetic resonance (MR) imaging for the differentiation of angiomyolipomas with minimal fat (mfAML) from other homogeneous solid renal tumors. METHODS: Between 2005 and 2010 in two institutions, all histologically proven homogenous solid renal tumors imaged with computed tomography and MR imaging, including GRE sequences, have been retrospectively selected. A total of 118 patients (mean age: 61 years; range: 20-87) with 119 tumors were included. Two readers measured independently the signal intensity (SI) on GRE images and calculated SI index (SII) and tumor-to-spleen ratio (TSR) on in-phase and opposed-phase images. Intra- and interreader agreement was obtained. Cut-off values were derived from the receiver operating characteristic (ROC) curve analysis. RESULTS: Twelve mfAMLs in 11 patients were identified (mean size: 2.8cm; range: 1.2-3.5), and 107 non-AML tumors (3.2cm; 1-7.8) in 107 patients. The intraobserver reproducibility of SII and TSR was excellent with an intraclass correlation coefficient equal to 0.99 [0.98-0.99]. The coefficient of correlation between the readers was 0.99. The mean values of TSR for mfAMLs and non-mfAMLs were -7.0±22.8 versus -8.2±21.2 for reader 1 and -6.7±22.8 versus -8.4±20.9 for reader 2 respectively. No significant difference was noticed between the two groups for SII (p=0.98) and TSR (p=0.86). Only 1 out of 12 mfAMLs and 11 of 107 non-AML tumors presented with a TSR inferior to -30% (p=0.83). CONCLUSION: In a routine practice, GRE sequences cannot be a confident tool to differentiate renal mfAMLs from other homogeneous solid renal tumors.


Sujet(s)
Angiomyolipome/diagnostic , Tumeurs du rein/diagnostic , Rein/anatomopathologie , Imagerie par résonance magnétique/méthodes , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Angiomyolipome/anatomopathologie , Diagnostic différentiel , Femelle , Humains , Tumeurs du rein/anatomopathologie , Mâle , Adulte d'âge moyen , Courbe ROC , Reproductibilité des résultats , Études rétrospectives , Sensibilité et spécificité , Tomodensitométrie
6.
Diagn Interv Imaging ; 96(1): 65-71, 2015 Jan.
Article de Anglais | MEDLINE | ID: mdl-25547671

RÉSUMÉ

PURPOSE: To investigate the correlation and concordance between the ellipsoid volume calculated by ultrasonography measurements (Vol3DUS) and the reference kidney volume measured by CT (VolTDM) in early autosomal dominant polycystic kidney disease (ADPKD). MATERIALS AND METHODS: Prospective study of the correlation and concordance of renal volumes in 24 patients with early ADPKD (48 kidneys analysed separately), with calculation of Vol3DUS using the formula for an ellipsoid in three different manners and VolTDM measurement by manual contouring. Calculations of correlation coefficients (r) and coefficients of intra-class correlation (ICC) with confidence intervals at 95%. RESULTS: The US volume was strongly correlated with the CT volume by using the maximum width in a transverse section (r=0.83) with a mean Vol3DUS=692±348ml [180; 2069]. The most reproducible ultrasonography measurement was the height. When the kidney volume exceeded 800ml, US underestimated the volume. However, the median error was -57.5ml [-1090; 183] and 85% of the Vol3DUS calculated differed by more than 5% from the reference measurement. CONCLUSION: The correlation between the US calculated volumes and the CT volumes was strong. However, the median error with ellipsoid US volume was too high to detect a small renal variation in early ADPKD.


Sujet(s)
Rein/imagerie diagnostique , Rein/anatomopathologie , Polykystose rénale autosomique dominante/imagerie diagnostique , Polykystose rénale autosomique dominante/anatomopathologie , Adulte , Femelle , Humains , Mâle , Adulte d'âge moyen , Taille d'organe , Études prospectives , Tomodensitométrie , Échographie
7.
Diagn Interv Imaging ; 95(11): 1055-63, 2014 Nov.
Article de Anglais | MEDLINE | ID: mdl-25443332

RÉSUMÉ

PURPOSE: To describe the CT and MRI appearances of papillary renal cell carcinoma. MATERIALS AND METHODS: Retrospective study of 102 papillary carcinomas in 79 patients, 81 tumors examined by CT and 56 by MRI. Tumor size, homogeneity and contrast enhancement were recorded. RESULTS: The most common presentation of papillary renal cell carcinoma was a small homogeneous hypovascular tumor both on CT and MRI. Eighty-nine percent of lesions were hypointense on T2 weighted images compared to the renal parenchyma. Seventeen percent of the lesions did not significantly enhance with contrast on CT. All of the lesions examined on MRI had a significant enhancement percentage. Calcifications were rare and only seen in 7% of cases (CT). The second most common presentation was a bulky necrotic tumor. In addition, atypical types of disease were found which were difficult to diagnose, including infiltrating tumors and tumors with a fatty component. CONCLUSION: A homogeneous hypovascular renal tumor which is hypointense on T2 weighted images should suggest a diagnosis of papillary carcinoma. Some papillary carcinomas do not enhance significantly on CT. MRI is then required to diagnose the renal tumor.


Sujet(s)
Néphrocarcinome/diagnostic , Tumeurs du rein/diagnostic , Imagerie par résonance magnétique , Tomodensitométrie , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Amélioration d'image , Rein/anatomopathologie , Mâle , Adulte d'âge moyen , Invasion tumorale , Études rétrospectives , Charge tumorale , Jeune adulte
8.
Eur J Radiol ; 83(3): 442-9, 2014 Mar.
Article de Anglais | MEDLINE | ID: mdl-24495906

RÉSUMÉ

Nowadays ultrasound elastosonography is an established technique, although with limited clinical application, used to assess tissue stiffness, which is a parameter that in most cases is associated with malignancy. However, although a consistent number of articles have been published about several applications of elastosonography, its use in certain human body districts is still not well defined. In this paper we write on the use of elastosonography in prostate, testicle and musculo-skeletal apparatus. We report and compare the work of several authors, different type of elastosonography (shear wave, strain elastography, etc.) and instrumental data obtained in the study of both benign and malignant lesions.

12.
Eur J Radiol ; 82(11): 1904-12, 2013 Nov.
Article de Anglais | MEDLINE | ID: mdl-23816164

RÉSUMÉ

Nowadays ultrasound elastosonography is an established technique, although with limited clinical application, used to assess tissue stiffness, which is a parameter that in most cases is associated with malignancy. However, although a consistent number of articles have been published about several applications of elastosonography, its use in certain human body districts is still not well defined. In this paper we write on the use of elastosonography in prostate, testicle and musculo-skeletal apparatus. We report and compare the work of several authors, different type of elastosonography (shear wave, strain elastography, etc.) and instrumental data obtained in the study of both benign and malignant lesions.


Sujet(s)
Dépistage précoce du cancer/méthodes , Imagerie d'élasticité tissulaire/méthodes , Amélioration d'image/méthodes , Maladies musculaires/imagerie diagnostique , Tumeurs de la prostate/imagerie diagnostique , Tendinopathie/imagerie diagnostique , Maladies testiculaires/imagerie diagnostique , Femelle , Humains , Mâle
13.
Diagn Interv Imaging ; 94(5): 551-60, 2013 May.
Article de Anglais | MEDLINE | ID: mdl-23607924

RÉSUMÉ

Prostate cancer is the cancer exhibiting the highest incidence rate and it appears as the second cause of cancer death in men, after lung cancer. Prostate cancer is difficult to detect, and the treatment efficacy remains limited despite the increase use of biological tests (prostate-specific antigen [PSA] dosage), the development of new imaging modalities, and the use of invasive procedures such as biopsy. Ultrasound elastography is a novel imaging technique capable of mapping tissue stiffness of the prostate. It is known that prostatic cancer tissue is often harder than healthy tissue (information used by digital rectal examination [DRE]). Two elastography techniques have been developed based on different principles: first, quasi-static (or strain) technique, and second, shear wave technique. The tissue stiffness information provided by US elastography should improve the detection of prostate cancer and provide guidance for biopsy. Prostate elastography provides high sensitivity for detecting prostate cancer and shows high negative predictive values, ensuring that few cancers will be missed. US elastography should become an additional method of imaging the prostate, complementing the conventional transrectal ultrasound and MRI. This technique requires significant training (especially for quasi-static elastography) to become familiar with acquisition process, acquisition technique, characteristics and limitations, and to achieve correct diagnoses.


Sujet(s)
Imagerie d'élasticité tissulaire/méthodes , Amélioration d'image/méthodes , Traitement d'image par ordinateur/méthodes , Tumeurs de la prostate/imagerie diagnostique , Sujet âgé , Marqueurs biologiques tumoraux/sang , Biopsie , Endosonographie/méthodes , Femelle , Dureté , Humains , Mâle , Dépistage de masse , Adulte d'âge moyen , Grading des tumeurs , Prostate/imagerie diagnostique , Prostate/anatomopathologie , Antigène spécifique de la prostate/sang , Tumeurs de la prostate/anatomopathologie , Sensibilité et spécificité
14.
Diagn Interv Imaging ; 94(5): 535-44, 2013 May.
Article de Anglais | MEDLINE | ID: mdl-23623210

RÉSUMÉ

Thyroid nodules are very common, while thyroid cancer is rare and has a very good prognosis. Thyroid nodule ultrasound characterization performed by experienced clinicians allows the selection of the tumours to be punctured and guiding fine needle aspiration (FNA). FNA provide cytology information able to differentiate benign tumours from cancer in approximately 80% of cases. However, it remains difficult to identify thyroid cancers with ultrasound imaging, as demonstrated by the very low rate of cancers detected in all of the carried out FNA (approximately 5%). As a majority of thyroid cancers are hard, the stiffness evaluation has become part of nodular characterization. Since 2005, elastography has been used for the evaluation of thyroid nodules; quasi-static elastography was the first technique available and used, at first, an external pressure induced by the probe, which was then replaced by carotid internal excitation allowing improvement in sensitivity. Semi-quantitative analysis allows comparison of tissue elasticities between tissue with elasticity anomalies and normal tissue and provides therefore useful analytic information. Shear wave elastography (SWE) provides a map of the elasticity in a region and allows stiffness quantification of lesions in kilopascals in order to reinforce the predictive value of malignancy. A tumour whose stiffness is greater than 65kPa or for which the stiffness ratio is greater than 3.7 compared to surrounding healthy tissue is highly suspicious. SWE may enable the detection of malignant follicular tumours that currently escape detection by the ultrasound-guided ultrasound/aspiration cytology couple. Lymph node metastasis of papillary thyroid cancer can also be detected by elastography due to its increased stiffness.


Sujet(s)
Imagerie d'élasticité tissulaire/méthodes , Amélioration d'image/méthodes , Interprétation d'images assistée par ordinateur/méthodes , Tumeurs de la thyroïde/imagerie diagnostique , Nodule thyroïdien/imagerie diagnostique , Adénocarcinome folliculaire/imagerie diagnostique , Adénocarcinome folliculaire/anatomopathologie , Adénocarcinome papillaire/imagerie diagnostique , Adénocarcinome papillaire/anatomopathologie , Cytoponction , Carcinome médullaire/imagerie diagnostique , Carcinome médullaire/anatomopathologie , Diagnostic différentiel , Humains , Métastase lymphatique/imagerie diagnostique , Métastase lymphatique/anatomopathologie , Sensibilité et spécificité , Glande thyroide/imagerie diagnostique , Glande thyroide/anatomopathologie , Tumeurs de la thyroïde/anatomopathologie , Nodule thyroïdien/anatomopathologie , Échographie interventionnelle
15.
Gynecol Obstet Fertil ; 40(9): 481-9, 2012 Sep.
Article de Français | MEDLINE | ID: mdl-22902716

RÉSUMÉ

Assessment of male infertility includes clinical examination, laboratory tests (semen analysis, hormones dosage) and sonographic examination of the urogenital tract. Male infertility is due to testicular abnormalities (secretory type) or obstructive disorder (excretory type). Imaging should provide accurate definition of anatomical causes of infertility in order to deliver appropriate treatment. Testicular Doppler ultrasound with transrectal ultrasound is the gold standard imaging technique to explore male infertility. MRI, because of its high resolution, provides a multiplanar study especially in congenital and inflammatory abnormalities of the urogenital tract. This pictorial review illustrates the most frequent causes of male infertility.


Sujet(s)
Imagerie diagnostique/méthodes , Infertilité masculine/anatomopathologie , Humains , Infertilité masculine/imagerie diagnostique , Infertilité masculine/étiologie , Imagerie par résonance magnétique , Mâle , Analyse du sperme , Maladies testiculaires/complications , Maladies testiculaires/anatomopathologie , Maladies testiculaires/physiopathologie , Testicule/malformations , Testicule/imagerie diagnostique , Testicule/anatomopathologie , Échographie
16.
Diagn Interv Imaging ; 93(4): 232-45, 2012 Apr.
Article de Anglais | MEDLINE | ID: mdl-22476035

RÉSUMÉ

The reference method for characterising a solid renal mass is computed tomography. MRI and ultrasound can provide useful diagnostic information for characterising masses the cystic or solid nature of which it is not possible to determine from data from the CT scan. For characterising a solid mass, only MRI can replace the CT scan in most cases. Once a mass has been shown to be solid and vascularised and not occurring in a context suggesting an inflammatory pseudotumour, it can be put, using CT, into one of the four categories of the classification that we propose: pseudotumoral dysmorphisms (type 1); typical high-fat angiomyolipomas (type 2); suspect indeterminate tumours (type 3); typically malignant tumours (type 4).


Sujet(s)
Tumeurs du rein/classification , Tumeurs du rein/diagnostic , Imagerie par résonance magnétique , Tomodensitométrie , Humains
17.
J Radiol ; 92(4): 299-307, 2011 Apr.
Article de Français | MEDLINE | ID: mdl-21549886

RÉSUMÉ

The purpose of this article is to review the diagnostic work-up of renal failure, acute or chronic. The role of the radiologist is to exclude the presence of a curable etiology such as urinary tract obstruction or vascular thrombosis. Renal ultrasound with Doppler imaging is the imaging modality of choice for this indication, and the use of a contrast agent is useful to evaluate renal perfusion. Non-contrast CT remains valuable for the diagnosis of some urinary tract pathologies. Finally, MRI is the most comprehensive imaging modality for the evaluation of the urinary tract, but performed as a second line modality mainly for practical reasons but also due to the non-negligible risk of nephrogenic systemic fibrosis secondary to the intravenous administration of gadolinium based contrast agent.


Sujet(s)
Atteinte rénale aigüe/diagnostic , Défaillance rénale chronique/diagnostic , Atteinte rénale aigüe/étiologie , Adulte , Anurie/étiologie , Produits de contraste/administration et posologie , Produits de contraste/effets indésirables , Diagnostic différentiel , Embolisation thérapeutique , Femelle , Gadolinium/effets indésirables , Humains , Nécrose du cortex rénal/diagnostic , Défaillance rénale chronique/étiologie , Imagerie par résonance magnétique/méthodes , Fibrose systémique néphrogénique/induit chimiquement , Fibrose systémique néphrogénique/prévention et contrôle , Hémorragie de la délivrance/thérapie , Sensibilité et spécificité , Tomodensitométrie/méthodes , Échographie-doppler , Maladies urologiques/diagnostic , Artère utérine
18.
J Radiol ; 92(4): 308-22, 2011 Apr.
Article de Français | MEDLINE | ID: mdl-21549887

RÉSUMÉ

Cystic kidney diseases often are discovered at the time of initial work-up of renal failure through ultrasound or family history, or incidentally at the time of an imaging test. Hereditary diseases include autosomal dominant or recessive polycystic kidney disease (PKD), tuberous sclerosis (TS) and medullary cystic kidney disease (MCKD). Autosomal dominant PKD is characterized by large renal cysts developing in young adults. Renal failure is progressive and becomes severe around 50-60 years of age. Atypical cysts (hemorrhagic or hyperdense) are frequent on CT and MRI examinations. Imaging plays a valuable role in the management of acute complications such as cyst hemorrhage or infection. Autosomal recessive PKD is often detected in neonates, infants or young adults. It is characterized by renal enlargement due to the presence of small cysts and liver disease (fibrosis and biliary ductal dilatation). Late manifestation or slow progression of autosomal recessive PKD may be more difficult to distinguish from autosomal dominant PKD. These cystic kidney diseases should not be confused with non-hereditary incidental multiple renal cysts. In tuberous sclerosis, renal cysts are associated with angiomyolipomas and sometimes pulmonary lymphangioleiomyomatosis. Renal failure is inconstant. Other hereditary cystic kidney diseases, including MCKD and nephronophtisis, are usually associated with renal failure. Non-hereditary cystic kidney diseases include multicystic renal dysplasia (due to complete pelvi-ureteric atresia or hydronephrosis), acquired multicystic kidney disease (chronic renal failure, chronic hemodialysis) and varied cystic kidney diseases (multicystic renal disease, glomerulocystic kidney disease, microcystic kidney disease).


Sujet(s)
Imagerie diagnostique/méthodes , Maladies kystiques rénales/diagnostic , Maladies kystiques rénales/génétique , Insuffisance rénale/diagnostic , Insuffisance rénale/génétique , Adulte , Sujet âgé , Diagnostic différentiel , Humains , Nourrisson , Nouveau-né , Imagerie par résonance magnétique/méthodes , Mâle , Adulte d'âge moyen , Polykystose rénale autosomique dominante/diagnostic , Polykystose rénale autosomique dominante/génétique , Polykystose rénale autosomique récessive/diagnostic , Polykystose rénale autosomique récessive/génétique , Complexe de la sclérose tubéreuse/diagnostic , Complexe de la sclérose tubéreuse/génétique , Échographie/méthodes , Jeune adulte
19.
Ultraschall Med ; 31(4): 363-9, 2010 Aug.
Article de Anglais | MEDLINE | ID: mdl-20408121

RÉSUMÉ

PURPOSE: The aim of the study was to evaluate a new method for the quantification of renal blood flow using contrast-enhanced ultrasound (CEUS) in an ex vivo pig kidney model. MATERIAL AND METHODS: After approval by the animal ethics committee, 4 pig kidneys were explanted and perfused with Celsior liquid (Imtix Sangstat, Lyon, France) at different flow rates (30, 50, 70 and 90 ml/min) in an ex vivo phantom. A 50 % diluted solution of SonoVue (Bracco, Milano, Italy) was infused in the artery at 0.5 ml/min. CEUS was performed with an Aplio system (Toshiba, Nasu, Japan) using a broadband linear transducer and pulse subtraction imaging. A total of 152 destruction-reperfusion sequences were acquired and cine loops were digitally stored for further quantification. Three different ROIs were placed upon the anterior, posterior cortex and segmental artery. Signal intensity measurements were performed in linear units and perfusion parameters were automatically extracted using dedicated software. Curve fitting was performed using a monoexponential model in which a time delay parameter was introduced. This fit allowed the assessment of the local blood flow into the region of interest (called "contrast-enhanced blood flow" (CEBF)). The artery mean signal intensity was averaged from the ten frames prior to the destruction phase. The normalized CEBF (nCEBF) was calculated as the ratio between CEBF and the mean arterial signal intensity. The CEBF and nCEBF were compared to the true blood flow indicated by the pump flow rate. RESULTS: The CEBF was correlated to the true blood flow only for the posterior cortical ROI (R(2) = 0.45, p = 0.05). The normalization using arterial signals improved CEBF correlation to true blood flow: nCEBF became correlated to the true blood flow when considering all ROIs (R(2)= 0.94, p < 0.0001) and correlation was improved for both anterior and posterior cortical ROIs (R(2)= 0, 93, p = 0.0004; R(2)= 0, 90, p = 0.0005, respectively). However, a significant kidney-dependent effect was observed for the anterior cortical ROI (p = 0.017) but not for the posterior cortical ROI (p = 0.89). CONCLUSION: Normalization using arterial signals significantly improved the estimation of blood flow calculated with CEUS.


Sujet(s)
Produits de contraste/administration et posologie , Amélioration d'image , Traitement d'image par ordinateur , Rein/vascularisation , Fantômes en imagerie , Phospholipides , Hexafluorure de soufre , Échographie-doppler couleur , Animaux , Vitesse du flux sanguin/physiologie , Humains , Valeurs de référence , Débit sanguin régional/physiologie , Sensibilité et spécificité , Logiciel , Suidae
20.
J Radiol ; 90(3 Pt 2): 362-70, 2009 Mar.
Article de Français | MEDLINE | ID: mdl-19421127

RÉSUMÉ

All ultrasound examinations for thyroid nodule should include a malignancy risk assessment based on the markedly hypoechoic nature of the nodule, presence of microcalcifications, ill-defined margins, nodule with shape taller than wide and intra-nodular hypervascularity at color Doppler. In patients with multinodular thyroid gland, precise nodule mapping is necessary to allow accurate follow-up of each nodule, correctly identify which nodule(s) is hyper functioning on iodine scan (if done) and guide fine needle aspiration (FNA) of suspicious nodules. As such, all reports of US examinations for thyroid nodule(s) should include a diagram or map of the nodule(s). An evaluation of cervical lymph nodes also helps to determine the malignancy risk. The main US features for malignant adenopathy include: rounded lymph node, loss of normal echogenic fatty hilum, and loss of normal hilar vascularization. Several patterns are highly suggestive of thyroid cancer metastasis: microcalcifications, cystic components, hyperechoic nodes, mimicking thyroid tissue. FNA is a routine procedure in experienced hands. It is the best test to determine which nodule(s) needs to be surgically removed. Thyroglobulin assay on needle-washing fluids after FNA is mandatory when lymph node metastasis is suspected. Preoperative lymph nodes mapping with neck ultrasound is commonly repeated prior to surgery to assess the need for node dissection in patients with proven thyroid malignancy.


Sujet(s)
Carcinome médullaire/imagerie diagnostique , Carcinome médullaire/anatomopathologie , Tumeurs de la thyroïde/imagerie diagnostique , Tumeurs de la thyroïde/anatomopathologie , Nodule thyroïdien/imagerie diagnostique , Nodule thyroïdien/anatomopathologie , Biométrie , Cytoponction , Carcinome médullaire/chirurgie , Femelle , Humains , Lymphadénectomie , Métastase lymphatique/diagnostic , Métastase lymphatique/imagerie diagnostique , Scintigraphie , Appréciation des risques , Glande thyroide/anatomopathologie , Tumeurs de la thyroïde/chirurgie , Nodule thyroïdien/chirurgie , Échographie-doppler couleur
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