"Triple low" free-breathing CTPA protocol for patients with dyspnoea.

AIM: To assess the performance of a "triple-low" free-breathing protocol for computed tomography pulmonary angiography (CTPA) evaluated on patients with dyspnoea and suspected pulmonary embolism and discuss its application in routine clinical practice for the study of the pulmonary parenchyma and vasculature. MATERIAL AND METHODS: This study was conducted on a selected group of dyspnoeic patients referred for CTPA. The protocol was designed using fast free-breathing acquisition and a small, fixed volume (35 ml) of contrast agent in order to achieve a low-exposure dose. For each examination, radiodensity of the pulmonary trunk and ascending aorta, and the dose-length product (DLP) were recorded. A qualitative analysis was performed of pulmonary arterial enhancement and the pulmonary parenchyma. RESULTS: This study included 134 patients. Contrast enhancement of the pulmonary arteries (409 ± 159 HU) was systematically >250 HU. The duration of acquisition ranged from 0.9 to 1.3 seconds for free-breathing imaging. The mean DLP was in the range of low-dose chest CT acquisitions (145 ± 73 mGy·cm). The analysis was deemed optimal in 90% (120/134) of cases for the pulmonary parenchyma. Sixty-nine per cent (92/134) of cases demonstrated homogeneous enhancement of the pulmonary arteries to the subsegmental level. Only 6% (8/134) of examinations were considered uninterpretable. CONCLUSION: The present "triple-low" CTPA protocol allows convenient analysis of the pulmonary parenchyma and arteries without hindrance by respiratory motion artefacts in dyspnoeic patients.

Qualitative and quantitative contrast-enhanced ultrasonography for the characterisation of non-palpable testicular tumours.

AIM: To assess the diagnostic performance of conventional ultrasound (US) and contrast-enhanced ultrasonography (CEUS) in the differential diagnosis of non-palpable intratesticular tumours. MATERIALS AND METHODS: The local ethics review board approved the protocol, and all of the patients provided written informed consent. Between December 2011 and February 2014, men with non-palpable testicular tumours and normal tumour markers who were referred for surgery were included. The tumours were analysed by conventional US, including B-mode and colour Doppler US (CDUS) as well as by CEUS. Morphological aspects and qualitative and quantitative CEUS criteria, based on visual enhancement and time-intensity curves, were assessed for each lesion. RESULTS: Forty patients were ultimately included. Based on histopathological results, the tumours were classified into three groups: benign tumours (n=16), malignant tumours (n=15), and burned-out tumours (n=9). In B-mode, the morphological aspects were significantly different between benign and malignant tumours (p-values from 0.0002 to 0.008). Qualitative and quantitative analyses of the CEUS images revealed that burned-out tumours exhibited significantly less enhancement than malignant and benign tumours: in burned-out tumours, time-intensity curves were flat, whereas in both benign and malignant tumours the curves had a bell-shaped pattern. All intensity parameters were lower for burned-out tumours compared to benign and malignant tumours (p-value from 0.0001 to 0.026). Both benign and malignant tumours enhanced strongly, however, and no significant difference between the two was noted (p-value from 0.0721 to 0.0953). CONCLUSION: Unlike conventional US, which enable benign lesions to be differentiated from malignant or burned-out tumours, CEUS failed to enabled differentiation between benign lesions and malignant vascularised testicular tumours. CEUS appears to have the potential, however, to differentiate burned-out tumours from vascularised testicular tumours.

Kidney cortex segmentation in 2D CT with U-Nets ensemble aggregation.

PURPOSE: This work presents our contribution to one of the data challenges organized by the French Radiology Society during the Journées Francophones de Radiologie. This challenge consisted in segmenting the kidney cortex from coronal computed tomography (CT) images, cropped around the cortex. MATERIALS AND METHODS: We chose to train an ensemble of fully-convolutional networks and to aggregate their prediction at test time to perform the segmentation. An image database was made available in 3 batches. A first training batch of 250 images with segmentation masks was provided by the challenge organizers one month before the conference. An additional training batch of 247 pairs was shared when the conference began. Participants were ranked using a Dice score. RESULTS: The segmentation results of our algorithm match the renal cortex with a good precision. Our strategy yielded a Dice score of 0.867, ranking us first in the data challenge. CONCLUSION: The proposed solution provides robust and accurate automatic segmentations of the renal cortex in CT images although the precision of the provided reference segmentations seemed to set a low upper bound on the numerical performance. However, this process should be applied in 3D to quantify the renal cortex volume, which would require a marked labelling effort to train the networks.

[MRI and staging evaluation of prostate cancer]. / IRM et bilan d'extension du cancer de la prostate.

MRI can assess local and locoregional spread of a newly diagnosed prostate cancer by detecting extracapsular extension (ECE), seminal vesicle invasion (SVI) and lymph node invasion. Endorectal MRI remains the only accurate means to assess local extension. Pelvic MRI with surface coils and the use of superparamagnetic particules provide the sensitivity and the specificity which have never been obtained by the sole measurement of node size of the lymphatic chains draining the prostate gland. With the endorectal coil, only direct signs of extracapsular extension have been maintained and indirect signs have been discarded, giving their too low specificity. Early SVI can only be consistently detected if result of TRUS guided biopsies show involvement of the prostate base. With the pelvic phased array coil, superparamagnetic particules show that metastatic lymph nodes have a specific MR signal which can be detected in normal size nodes. Indications of imaging relies on results of parametrers available before MR imaging. More important than PSA level and Gleason score on biopsies is the so called quantitative histology, represented by the number of sextants involved by tumor and the amount of cancer (measured in mm of tumor) present on biopsies which determine a risk of extraprostatic spread. Of the risk of extraprostatic spread depends indication of MR, which is most probably unnecessary in patients at low risk (<20%) of extraprostatic extension.

[One day diagnosis for breast lesions: Medical and psychological assessment--EVADIASEIN study]. / Diagnostic en un jour des lésions du sein: évaluation médicale et psychologique de la prise en charge--étude EVADIASEIN.

INTRODUCTION: Breast cancer is the most frequent feminine cancer in France and its incidence increases steadily. The time of access to medical care is an indicator of the quality of the treatments recommended by the Plan Cancer 2009-2013, as it influences the diagnosis and reduces psychological morbidity during the pre-diagnosis phase. The one-day diagnosis is a recently initiated concept, which offers to get the results of the biopsy on the day it is performed and facilitates the setting-up of therapeutic care with the surgeon met during the one-day medical consultations. The aim of this study is to evaluate the satisfaction of patients who benefited from a one-day breast lesion diagnosis, as well as confirm the decrease of time of access to medical treatment. METHODS: This is an observational, non-interventional and single-centre study based on 27 patients who benefited from one-day breast lesions diagnosis over two years. The patients were only included who had a classified lesion ACR 4 or 5 and visible in the ultrasound. We analyzed the histological concordance between the biopsy and the definitive histology, the time of access to medical care, and the therapeutic treatments We analyzed the psychological impact of such an organization by sending to the patients a questionnaire including the Psychological Consequence Questionnaire (PCQ) and the Breast Cancer Anxiety Indicator (BCA) allowing to estimate the anxiety generated by the pre-diagnostic phase, the DC-Sat allowing to estimate the satisfaction of the consultation of announcement, as well as the same day diagnosis benefit. RESULTS: The patients were 59.8 years old in average [33-87]. The average time between the date of the mammography and the one-day diagnosis consultation (including the biopsy) was 15.0 days [0-60]. Fifty-seven percent of the patients considered this time as short. The average time between the biopsy date and the start of the treatment was 15.9 days [4-30]. The one-day diagnosis took an average of 1.6 days [1-5]. The results of the PCQ showed an important emotional impact during the diagnosis phase, and the average BCA score reached an average of 3.9 on a scale of 5. However, the patients were very satisfied with the diagnosis consultation with an average of 8.7 on a scale of 10, and 95% think the one-day diagnosis is beneficial to the patients. DISCUSSION: This study shows that the one-day breast-damage diagnosis enables to improve the time of access to care, and meets the current recommendations. Even though faster access to treatment does not reduce the psychological morbidity of awaiting diagnosis, the patients express their satisfaction and find the rapidity of the pre-diagnosis phase beneficial. CONCLUSION: In view of this study, the one-day breast-damage diagnosis appears to be a quality feature in the process of access to care and treatment of the patients.

MR imaging features of acute bilateral renal cortical necrosis.

Bilateral renal cortical necrosis (BRCN) is an uncommon cause of acute renal failure. Kidney biopsy, arteriography, and contrast-enhanced computed tomography (CT) are usually used to diagnose BRCN. However, these methods can have potentially serious side effects. We report two cases in which magnetic resonance imaging (MRI) evidenced characteristic features of BRCN, which were confirmed by histological findings and arteriography and correlated with clinical evolution. In the first case report, the diagnosis of a massive and complete cortical necrosis variety was suggested on MRI that showed a thin rim of low signal intensity along border of kidneys. It was confirmed on kidney biopsy, and the renal function did not recover. The second case is an incomplete form with cortical patchy areas of low signal intensity. In these two patients, MRI helped to establish an early diagnosis of BRCN with characteristic representative findings, without the potential nephrotoxic effects of iodinated contrast that has to be used in CT and arteriography. Kidney biopsy, besides the risks of complications, provides only a parceled analysis of the renal tissue and therefore does not allow any conclusion as to the extension of cortical necrosis. MRI may be of great help for the diagnosis and follow-up of acute renal cortical necrosis.

Review article: Overview of medical treatments in unresectable hepatocellular carcinoma--an impossible meta-analysis?

BACKGROUND: Controversies surrounding medical treatment in patients with unresectable hepatocellular carcinoma continue to persist. AIM: To perform a meta-analysis of therapeutic modalities which had been evaluated in two or more randomized trials. METHODS: Fifty-two randomized trials were studied; only 30 were included. This overview identified seven therapeutic modalities which had been evaluated in two or more trials: adriamycin, 5-fluorouracil, interferon, percutaneous ethanol injection, transarterial chemotherapy, the combination of lipiodol with transarterial chemotherapy, and tamoxifen. RESULTS: Comparisons of survival between control groups showed substantial heterogeneity. There was no survival benefit at 1 year with adriamycin (mean difference 4%), 5-fluorouracil (mean difference -3%), percutaneous ethanol injection (mean difference 6%) or transarterial chemotherapy (mean difference -2%). For interferon, the survival benefit was significant with the Der Simonian & Laird method (mean difference 9%, 95% CI = 1-18%, P = 0.04) but not with the Peto et al. method (2.4 mean odds ratio, 95% CI = 0.9-6.8). The meta-analysis of tamoxifen showed a borderline survival benefit (mean difference 25%, 95% CI = 0-49%, P = 0.05). However, in sensitivity analyses, the survival benefit of tamoxifen was no longer significant. CONCLUSIONS: No treatment has clearly proven efficacy in survival. 5-Fluorouracil, adriamycin and transarterial chemotherapy were not associated with survival benefit at 1 year. The number of randomized controlled trials was insufficient to enable a conclusion to be reached for interferon and percutaneous ethanol injection. Controversy persists concerning tamoxifen efficacy. Interferon and tamoxifen require new randomized controlled trials on a larger population of patients.

Primary retroperitoneal teratoma in the adult: correlation of MRI features with CT and pathology.

Primary benign teratoma of the retroperitoneum is a rare tumor in the adult population. Only one case with an MRI examination has been reported in the English literature. This paper describes the CT and MRI features of a retroperitoneal teratoma in a 24-year-old male and discusses the value of MRI in the diagnosis and the preoperative imaging of such a tumor.

Gd-DOTA: evaluation of its renal tolerance in patients with chronic renal failure.

Gd-DOTA is an intravenous contrast medium used in MRI. The clinical and biological tolerance of Gd-DOTA was studied in patients with chronic renal failure (e.g., those having a glomerular filtration rate of less than 60 mL/min). Twenty patients were randomized into two groups. In the control group, spin-echo (SE) T1- and T2-weighted images of the kidneys were obtained without injection of Gd-DOTA. In the DOTA-group, patients received 0.1 mmol/kg of Gd-DOTA. SE T1-weighted images were obtained before and after injections; a T2-weighted sequence was performed before injection. Clinical data, serum creatinine, and laboratory parameters were estimated before, and 24 and 48 hr after MRI. No adverse reaction was reported after injection of Gd-DOTA. Mean serum creatinine and glomerular filtration rate remained unchanged in both groups. For five patients in the control group and three patients in the DOTA-group the serum creatinine levels increased more than 10% and less than 25%. No evidence of nephrotoxicity was observed with Gd-DOTA in patients with chronic renal failure.

MRI of liver tumors using gadolinium-DOTA: prospective study comparing spin-echo long TR-te sequence and CT.

Thirty-nine patients with liver tumors were examined using MRI at 0.5 T before and after intravenous bolus injection of either 0.1 mmol/kg (n = 18) or 0.2 mmol/kg (n = 21) of Gadolinium-Dota, using spin-echo T1-and T2-weighted sequences before injections and spin-echo or gradient-echo sequences after injection. When contrast-to-noise (C/N) data were normalized relative to time, optimal mean C/N was observed after gadolinium injection. However, subjective study and case-by-case C/N measurement showed better contrast for SE 2000/60 and CT with injection in 62% and 42% of cases, respectively.

Iron oxide-enhanced MR lymphography: initial experience.

The detection of nodal metastases is of utmost importance in oncologic imaging. Ultrasmall superparamagnetic iron oxide particles (USPIO) are novel contrast agents specifically developed for MR lymphography. After intravenous administration, they are taken up by the macrophages of the lymph nodes, where they accumulate. They reduce the signal intensity (SI) of normally functioning nodes on postcontrast T2-and T2*-weighted images through the magnetic susceptibility effects on iron oxide. Metastatic nodes, in which macrophages are replaced by tumor cells, show no significant change in SI on postcontrast T2-and T2*-weighted images. Early clinical experience suggests that USPIO-enhanced MR lymphography improves the sensitivity and specificity for the detection of nodal metastases. It also suggests that micrometastases could be detected in normal-sized nodes. This article reviews the physiochemical properties of USPIO contrast agents, their enhancement patterns, and early clinical experience.

Role of CT in the study of recurrences of Hodgkin's disease on the chest wall. Report on 12 cases.

Twelve cases of recurrences of Hodgkin's disease on the chest wall, associated with three breast lesions and three diaphragmatic lesions, were studied by computed tomography (CT). Although the chest radiographs of all the patients were abnormal, CT was more accurate than clinical and other radiological examinations in delineating the lesions of the chest wall and in studying the extension of the relapse. Muscle enlargement was present in all cases. In seven cases osseous lesions and in seven cases pleural effusion or subpleural plaques were found. Chest wall recurrences were associated with other thoracic or abdominal lesions in 75% of the cases. Recurrences to the chest wall occur late (mean 6.3 years) in the evolution of Hodgkin's disease. They developed during the first relapse in 67% of the cases and during the second to the fourth relapse in 33% of the cases. CT is useful for the screening of lesions for which the outcome is bad. Only in four cases patients were without any evidence of disease after treatment.

[Contrast media in hepatic MRI]. / Produits de contraste en IRM hépatique.

This article is a review of the current commercial MR contrast media (gadolinium chelates) and of the products that are not yet on the market and are under trial in man (super-magnetic iron oxides, manganese compounds) or only in animals (ferric chelate, liposomes containing gadolinium compounds, gadolinium chelate/human serum albumin compounds, hepatic asialoglycoprotein receptors).

[Pitfalls of the dorsal decubitus in aortography]. / Piège du décubitus dorsal en aortographie.

The use of the prone position in aortography improves the visualization of the anterior wall of the aorta. This is supported by observation of an obstructed aortobifemoral by-pass and seems interesting in the study of aneurysms. More often, it is useful in case of decreased blood flow or increased local turbulence.

[Value of x-ray computed tomography in evaluating the spread and therapeutic strategy in cancer of the bladder]. / Intérêt de la tomodensitométrie dans le bilan d'extension et la stratégie thérapeutique du cancer de vessie.

Fifty four computed (CT) examinations were performed on patients with bladder carcinoma. A pathological assessment was obtained in 24 cases and the accuracy of CT in local staging was 91%. The accuracy of CT in detecting lymph nodes invasion was also 91%. Moreover, CT is helpful in the follow-up of patients under treatment. As it provides a correct pre-therapeutic evaluation in 83% cases, CT appears as an effective examination to perform in the evaluation of bladder carcinoma.

[Renal lymphoma in a patient after kidney transplantation and cyclosporine therapy]. / Lymphome rénal chez un transplanté traité par ciclosporine.

The effectiveness of renal transplantation has been considerably improved by the use of cyclosporine as an antirejection agent. However, because of those very same immunosuppressive properties, this substance may lead to several infectious or tumoral complications that raise complex therapeutic problems. This article reports about one case of immunoblastic lymphoma discovered in a patient who received renal transplantation and who had been treated with cyclosporine for two years.

[MRI techniques applied to the diagnosis of hepatic tumors]. / Techniques d'IRM appliquées au diagnostic des tumeurs hépatiques.

We know that the contrast of MR images can be better than that of CT scans. In the spin echo mode, sequences with long TR and long TE provide great contrast, while, conversely, sequences with short TR and TE produce images with a greater anatomical fidelity. This dual performance, a notion that had never been expressed as explicitly in imaging, has led to distinguishing between the roles of MRI for detection and tissue characterization (diagnosis and nature). While the choice of an appropriate sequence for characterization has apparently been made immediately with a modulation of T2 weighting, the selection of a detection sequence is less easy. The number of parameters involved (signal-to-noise and contrast-to-noise ratios, spatial resolution, artifacts, imaging time) and the compromise arrangements needed to take them into account explain the lack of consensus as to the optimal sequence for detection. Instead of becoming simpler with time, the issue is increasingly complex, as now fast imaging has been developed in addition to conventional spin echo imaging, and may even supersede it.

[Lymphography and x-ray computed tomography in the evaluation of lymph node invasiveness in cancer of the bladder. Comparison of their diagnostic value]. / Lymphographie et tomodensitométrie dans le bilan d'extension ganglionnaire des cancers de la vessie. Comparaison de leur valeur diagnostique.

The diagnostic value of lymphography and computed tomography (CT) in the assessment of lymph node invasion by bladder cancers has been compared on the basis of 30 observations. Although computed tomography apparently yields better results (reliability: 93%) than lymphography (reliability: 87%), these findings have no statistical significance. The study of literature shows that the statistical exploitation of the results was seldom carried out. The combination of both exploration techniques seems to improve predictive values, but this improvement was not statistically significant in our study.

[Renal tolerance of iodinated low osmolality contrast agents. Clinical and experimental aspects]. / Tolérance rénale des produits de contraste iodés de basse osmolalité. Aspects expérimentaux et cliniques.

The low osmolality iodinated contrast agents (ICA), ionic or non ionic are now suggested too replace the usual high osmolality ICA. The main arguments are the better clinical tolerance and a lower renal toxicity. Recent experimental studies have clearly demonstrated that the low osmolality ICA presents a lower renal toxicity. On the rat, we have confirmed that the in vivo renal toxicity of low osmolality ICA, is lower than the high osmolality ICA toxicity. It is clearly demonstrated on man than the enzyme urinary excretion and proteinuria are little or not modified by the low osmolality ICA, but both are increased by high osmolality ICA. These changes are found with a normal glomerular filtration flow. No difference are noted in the creatinine concentration and clearance follow-up. However it is possible that the necessary population of patient to get statistically significative differences between both agents can be superior to the number of patients studied. In clinical practice, we think, that low osmolality ICA must be used for patients presenting one or several risk factors of acute renal failure.