Tubulocystic renal cell carcinoma: a new radiological entity.

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.

Renal blood flow quantification in pigs using contrast-enhanced ultrasound: an ex vivo study.

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.

CT-guided infiltration of greater occipital nerve for refractory craniofacial pain syndromes other than occipital neuralgia.

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.

[Thyroid nodule management: ultrasonography, fine-needle cytology]. / Conduite à tenir devant un nodule thyroïdien: échographie, cytoponction.

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.

[The imaging aspects of metastases from urological malignancies]. / Aspects radiologiques des métastases des cancers urologiques.

Metastases from cancers in urology do not exhibit specific radiological patterns that would allow identification of the primary site. Their detection relies upon usual imaging techniques, and mainly contrast-enhanced Computed Tomography (CT) that allows the study of the thorax, the abdomen and the pelvis. Ultrasound imaging, and the up-to-date contrast-enhanced ultrasound imaging, as well as Magnetic Resonance Imaging are used in addition to CT in case of contra indication of iodinated contrast agents or for targeted indications (focal liver lesion characterization, MR lymphography for lymph node metastases...). PET CT is playing an increasing role but its performances remain limited for the detection of urological metastases. New anti-angiogenic drugs are questioning the traditional evaluation of the therapeutic response based on RECIST criteria. They require more and more the use of functional imaging techniques, such as MRI or CT dynamic studies as well as contrast-enhanced ultrasound.

Simple and complex renal cysts in adults: Classification system for renal cystic masses.

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.

[Renal oncocytoma: CT diagnostic criteria revisited]. / Adénome oncocytaire du rein: redéfinition des critères diagnostiques en tomodensitométrie.

PURPOSE: To redefine and evaluate the computed tomographic criteria for the diagnosis of renal oncocytoma (RO) for which renal sparing surgery should be preferred. MATERIAL AND METHOD: Retrospective study of 57 patients with 69 RO. Macroscopic and histological correlation was obtained in all cases. A double blinded comparative study was made of 60 renal tumors (containing adenocarcinomas and oncocytomas) larger than 3 cm in diameter in order to evaluate the redefined CT diagnostic criteria. RESULTS: Among RO larger than 3 cm in diameter, 55% presented a sharply defined low attenuation scar on post-contrast scans at the tubular nephrographic phase, central or eccentric, with homogeneous attenuation throughout the remainder of the hypervascular tumor which was classified in 3 different groups. The use of our CT diagnostic criteria gave a statistically significant (p < 0.05) Kappa index of inter-observer concordance of 0.71 and a specificity of 96% for the diagnosis of RO. CONCLUSION: Our redefined computed tomographic criteria for the diagnosis of renal oncocytoma, eventually associated with renal biopsy, should increase the indications for renal sparing surgery for RO larger than 3 cm in diameter.

Urinary endometriosis: MR imaging appearance with surgical and histological correlations.

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.

Double-echo gradient chemical shift MR imaging fails to differentiate minimal fat renal angiomyolipomas from other homogeneous solid renal tumors.

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.

Ultrasonographic renal volume measurements in early autosomal dominant polycystic disease: comparison with CT-scan renal volume calculations.

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.

Color Doppler-guided prostate biopsies in 591 patients with an elevated serum PSA level: impact on Gleason score for nonpalpable lesions.

OBJECTIVES: To compare results of color Doppler-guided ultrasonography (CDUS) versus those of systematic biopsies in 591 patients with an elevated serum PSA level and to correlate them with digital rectal examination (DRE) findings. METHODS: Biopsies were directed into hypervascularized (CDUS+) or hypovascularized (CDUS-) hypoechoic peripheral zone nodules (443 cases). When transrectal ultrasound (TRUS) was normal (148 cases), biopsies were directed into hypervascular area. Six additional posterior biopsies were also performed in every patient, together with four anterior biopsies in 117 patients with normal DRE and prostate weight above 40 g. RESULTS: Biopsies were positive in 339 patients (57%). Positive biopsy rate (PBR) of directed biopsies was 84% in hypervascular abnormalities (264 of 316) and 17% in hypovascular nodules (23 of 134) (P < 0.001). PBR of combined biopsies was 84% in CDUS+ patients (266 of 316) and 26% in CDUS- patients (73 of 275) (P < 0.001). Comparison of TRUS and CDUS showed a sensitivity of 0.9 and 0.78, respectively, and a specificity of 0.46 and 0.8, respectively. Of the 131 patients with a PSA level between 4 and 10 ng/mL and a normal DRE, PBR was 59% (22 of 37) when CDUS was positive and 11% (10 of 94) when it was negative, regardless of TRUS abnormalities (P < 0.001). Nonpalpable cancers with a negative CDUS showed a significantly (P < 0.001) lower Gleason score (5.5 +/- 0.9) than that of CDUS+ cancer (6.5 +/- 1.1). Eleven cancers were diagnosed by only anterior positive biopsies. All of them had a negative CDUS and a PSA level above 10 ng/mL. CONCLUSIONS: CDUS does not modify prostate biopsy policy except in patients with negative CDUS, normal DRE, and PSA level between 4 and 10 ng/mL, where deferment of biopsy can be advocated. Anterior biopsies are only useful in patients with a PSA level above 10 ng/mL and a negative CDUS.

Renovascular disease: Doppler ultrasound.

Color Doppler ultrasound (CDUS) seems to be an effective imaging technique for the diagnosis of renal vascular diseases. It is already the modality of choice for the detection of acute renal vein thrombosis and nonocclusive intrarenal vascular disorders including iatrogenic arteriovenous fistula and false aneurysm, particularly in patients with impaired renal function that precludes the use of iodinated contrast agents. Although proximal Doppler interrogation remains an important step in diagnosing renal artery (RA) stenosis, useful hemodynamic information can be obtained from the distal arterial bed. When CDUS fails in identifying proximal RAs, normal waveform velocity and morphology obtained from intrarenal arteries enable one to rule out RA occlusion and most of the severe stenoses (> or = 80%). Such information, which is not subject to a significant risk of technical failure, seems to be particularly useful in studying patients with acute renal failure of suspected vascular origin. Despite the extreme variability in reported performance between studies, CDUS has seemed to be a valuable tool compared with other noninvasive modalities in the diagnosis of RA stenosis. Whereas a CDUS-based strategy is already accepted in numerous specialized centers, a thorough evaluation of diagnostic criteria and extensive training of operators will allow CDUS to be widely accepted for the screening of patients at high risk for renovascular hypertension.

[Diagnostic quality control of hepatobiliary echography by autopsy correlation]. / Contrôle de la qualité diagnostique de l'échographie hépato-biliaire par corrélation autopsique.

A methodology to evaluate routine ultrasonography performed in liver pathology is described. The results of 62 autopsies, undoubtedly the most accurate anatomical reference, were compared to those of sonographic examination of the liver performed two months before death at the most. Discordance was found in 23 cases. False negative results in the detection of metastasis and thrombosis of hepatic veins or inferior vena cava were the major pitfalls. The reasons and the consequences of each error were determined for each case.

[Urinary tract imaging: conventional radiology and ultrasound]. / Exploration actuelle de l'appareil urinaire: radiologie conventionnelle et échographie.

Conventional radiology includes intravenous urography for evaluation of the entire urinary tract and direct opacifications by retrograde cystography, supra-pubic cystography, and retrograde urethro-cystography for evaluation of the lower urinary tract. Intravenous urography remains the gold standard for evaluation of the upper excretory tract. The accuracy of ultrasound examination has increased with the availability of multiple frequency probes, harmonic imaging and color Doppler imaging. Because it is non-invasive, ultrasound now is the first line imaging technique for evaluation of the renal parenchyma, renal vessels and bladder.

[Magnetic resonance imaging of the knee menisci. Normal aspects. Misleading images. Meniscus degeneration. Anatomic correlations]. / Imagerie par résonance magnétique des ménisques du genou. Aspects normaux. Images pièges. Dégénérescence méniscale. Corrélations anatomiques.

The authors report the result of a study on 5 knees of fresh corpses explored with magnetic resonance imaging, including 1 examined before and after intraarticular contrast injection, and on 15 asymptomatic subjects examined with the same procedure. A very thorough study of the menisci and of their attachment, ie. The tibial insertion of the menisceal horns, the transverse ligament, and the meniscofemoral ligament, is possible with T1-weighted MR sequences. The T2-weighted sequences, either following intraarticular contrast injection or in cases of articular effusion, allow analyzing the capsular attachments of the posterior horn of the lateral meniscus and its relationships with the tendon of the popliteal muscle. Five misleading images must be known for the exploration of the menisci, in order to avoid a number of interpretation problems. Images of type I and II initial meniscus degeneration are observed in 47% of all cases (control group). One case of menisceal cyst developing in the anterior horn of the lateral meniscus, with anatomical correlation, is also reported.

[Contrast-enhanced ultrasonography: renal applications]. / Echographie de contraste: les applications rénales.

Color Doppler US of the urinary tract is still facing a few limitations including, for B-mode imaging, the detection of small lesions, and, for color Doppler, the detection of low flow. Ultrasound contrast agents (USCA) improve these two limitations and allow the development of new functional applications for renal blood flow quantification. This improvement results from an increased acoustic response obtained from the microbubbles, as well as from the development of pulse sequencing and signal processing that led to the concept of specific ultrasound sequences. Most of the clinical indications of contrast-enhanced ultrasonography remain to be validated with the improved detection of the non linear response. USCA improve the detection of abnormal micro and macrovascular disorders of the kidney, particularly for the detection and the characterization of renal artery stenosis, as well as for the visualization of renal infarction. This technique showed potentials for the study of renal masses, especially atypical cystic lesions. Among the remaining indications, the detection of reflux and testicular torsion are the most promising.

[Diagnostic imaging of peripheral renal vascular disorders]. / Imagerie diagnostique de la pathologie vasculaire rénale périphérique.

Peripheral vascular disorders of the kidney involve the intrarenal branches of the renal vascular tree. It include occlusive (infarction and cortical necrosis) and non-occlusive vascular lesions (acquired arteriovenous fistulas, arteriovenous malformation, false aneurysms and microaneurysms). Initial diagnosis relies on color Doppler US and CT angiography. Angiography plays a therapeutic role. MR imaging provides useful diagnostic information on perfusion disorders especially in patients with renal insufficiency.