Amandine Crombe

MS Lesions Are Better Detected with 3D T1 Gradient-Echo Than with 2D T1 Spin-Echo Gadolinium-Enhanced Imaging at 3T

BACKGROUND AND PURPOSE: In multiple sclerosis, gadolinium enhancement is used to classify lesions as active. Regarding the need for a standardized and accurate method for detection of multiple sclerosis activity, we compared 2D-spin-echo with 3D-gradient-echo T1WI for the detection of gadolinium-enhancing MS lesions. MATERIALS AND METHODS: Fifty-eight patients with MS were prospectively imaged at 3T by using both 2D-spin-echo and 3D-gradient recalled-echo T1WI in random order after the injection of gadolinium. Blinded and independent evaluation was performed by a junior and a senior reader to count gadolinium-enhancing lesions and to characterize their location, size, pattern of enhancement, and the relative contrast between enhancing lesions and the adjacent white matter. Finally, the SNR and relative contrast of gadolinium-enhancing lesions were computed for both sequences by using simulations. RESULTS: Significantly more gadolinium-enhancing lesions were reported on 3D-gradient recalled-echo than on 2D-spin-echo (n = 59 versus n = 30 for the junior reader, P = .021; n = 77 versus n = 61 for the senior reader, P = .017). The difference between the 2 readers was significant on 2D-spin-echo (P = .044), for which images were less reproducible (κ = 0.51) than for 3D-gradient recalled-echo (κ = 0.65). Further comparisons showed that there were statistically more small lesions (<5 mm) on 3D-gradient recalled-echo than on 2D-spin-echo (P = .04), while other features were similar. Theoretic results from simulations predicted SNR and lesion contrast for 3D-gradient recalled-echo to be better than for 2D-spin-echo for visualization of small enhancing lesions and were, therefore, consistent with clinical observations. CONCLUSIONS: At 3T, 3D-gradient recalled-echo provides a higher detection rate of gadolinium-enhancing lesions, especially those with smaller size, with a better reproducibility; this finding suggests using 3D-gradient recalled-echo to detect MS activity, with potential impact in initiation, monitoring, and optimization of therapy.

Rare complications after lung percutaneous radiofrequency ablation: Incidence, risk factors, prevention and management

Among image-guided thermo-ablative techniques, percutaneous radiofrequency ablation (PRFA) is the most widely used technique for the treatment of primary and secondary lung malignancies. Tolerance of PRFA in the lung is excellent. However, relatively little is known about potential rare complications. This article presents both the clinical and imaging features of lung PRFA complications as well as their prevention and management. Complications may be classified in four groups: pleuropulmonary (e.g., bronchopleural or bronchial fistula, delayed abscess or aspergilloma inside post-PRFA cavitations, pulmonary artery pseudo aneurysm, gas embolism and interstitial pneumonia); thoracic wall and vertebral (e.g., rib or vertebral fractures and intercostal artery injury); mediastinal and apical (e.g., neural damage); or diaphragmatic. Most complications can be managed with conservative treatment, percutaneous or endoscopic drainage, or surgical repair.

Pulmonary artery pseudoaneurysm after radiofrequency ablation: report of two cases.

Abstract We report two cases of pulmonary arterial pseudoaneurysms (PAs) following percutaneous radiofrequency ablation (PRFA). The first patient was a 74-year-old Caucasian man who was treated for a secondary location of an advanced melanoma. A computed tomography scan at 72 h after the procedure, performed for basithoracic pain, hyperthermia and haemoptysis, revealed a 17-mm PA within the ablative zone. A lobectomy was performed. The second patient was an 80-year-old white man followed up for a right apical lung adenocarcinoma. Massive haemoptysis occurred 24 h after PRFA; emergent contrast-enhanced CT and pulmonary arteriography revealed a pulmonary artery PA (20 mm diameter), which was embolised with coils. The initial clinical course was satisfactory; however, 15 days after the procedure, the patient unfortunately presented a new massive haemoptysis and died a few hours later. The long ablation duration and the multiple repositioning of the electrodes might have been risk factors for this rare and potentially lethal complication.

23 Lung Metastases Treated by Radiofrequency Ablation Over 10 Years in a Single Patient: Successful Oncological Outcome of a Metastatic Cancer Without Altered Respiratory Function

An 82-year-old man, who was diagnosed in 2002 with an oncocytic (Hürthle cell) thyroid carcinoma, was initially treated by local surgery and was refractory to radioiodine treatment. The patient had successive secondary recurrences from 2006 onwards. Metastases were suspected due to an elevation of thyroglobulin in serum. Hypermetabolic nodules were targeted using FDG PET as well as CT-guided radiofrequency ablations. Thyroglobulin levels decreased following each procedure. 10 years later, tolerance and efficacy are excellent; 23 lung metastases have been treated during 11 sessions without current relapse. Respiratory function and quality of life are not altered. This report illustrates how radiofrequency ablation can be efficiently integrated into the long-term management of poorly aggressive oligometastatic cancer, in combination with other local and/or systemic therapies.

Multiple skeletal muscle metastases revealing a cardiac intimal sarcoma

We report the case of a 59-year-old female with progressive bilateral painful swelling of the thighs. MRI revealed multiple intramuscular necrotic masses with similar morphologic patterns. Whole-body CT and 18-FDG PET-CT scans demonstrated additional hypermetabolic muscular masses and a lobulated lesion within the left atrial cavity. As biopsy of a muscular mass was compatible with a poorly differentiated sarcoma with MDM2 oncogene amplification, two diagnoses were discussed: a dedifferentiated liposarcoma with muscle and heart metastases or a primary cardiac sarcoma, mainly a cardiac intimal sarcoma, with muscular metastases, which was finally confirmed by array-comparative genomic hybridization (aCGH) in a sarcoma reference center. This case emphasizes the potential for intimal sarcoma to disseminate in skeletal muscle prior to any other organ and the need for a genomic approach in addition to classical radiopathologic analyses to distinguish primary from secondary locations facing simultaneous tumors of the heart and skeletal muscles with MDM2 amplification.

Deciphering the microstructure of hippocampal subfields with in vivo DTI and NODDI: Applications to experimental multiple sclerosis.

&NA; The hippocampus contains distinct populations of neurons organized into separate anatomical subfields and layers with differential vulnerability to pathological mechanisms. The ability of in vivo neuroimaging to pinpoint regional vulnerability is especially important for better understanding of hippocampal pathology at the early stage of neurodegenerative disorders and for monitoring future therapeutic strategies. This is the case for instance in multiple sclerosis whose neurodegenerative component can affect the hippocampus from the early stage. We challenged the capacity of two models, i.e. the classical diffusion tensor imaging (DTI) model and the neurite orientation dispersion and density imaging (NODDI) model, to compute quantitative diffusion MRI that could capture microstructural alterations in the individual hippocampal layers of experimental‐autoimmune encephalomyelitis (EAE) mice, the animal model of multiple sclerosis. To achieve this, the hippocampal anatomy of a healthy mouse brain was first explored ex vivo with high resolution DTI and NODDI. Then, 18 EAE mice and 18 control mice were explored 20 days after immunization with in vivo diffusion MRI prior to sacrifice for the histological quantification of neurites and glial markers in each hippocampal layer. Fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD) maps were computed from the DTI model while the orientation dispersion index (ODI), the neurite density index (NDI) and the volume fraction of isotropic diffusivity (isoVF) maps were computed from the NODDI model. We first showed in control mice that color‐coded FA and ODI maps can delineate three main hippocampal layers. The quantification of FA, AD, RD, MD, ODI, NDI and isoVF presented differences within these 3 layers, especially within the molecular layer of the dentate gyrus which displayed a specific signature based on a combination of AD (or MD), ODI and NDI. Then, the comparison between EAE and control mice showed a decrease of AD (p = 0.036) and of MD (p = 0.033) selectively within the molecular layer of EAE mice while NODDI indices did not present any difference between EAE and control mice in any layer. Histological analyses confirmed the differential vulnerability of the molecular layer of EAE mice that exhibited decreased dendritic length and decreased dendritic complexity together with activated microglia. Dendritic length and intersections within the molecular layer were independent contributors to the observed decrease of AD (R2 = 0.37 and R2 = 0.40, p < 0.0001) and MD (R2 = 0.41 and R2 = 0.42, p < 0.0001). We therefore identified that NODDI maps can help to highlight the internal microanatomy of the hippocampus but NODDI still presents limitations in grey matter as it failed to capture selective dendritic alterations occurring at early stages of a neurodegenerative disease such as multiple sclerosis, whereas DTI maps were significantly altered. Graphical abstract Figure. No caption available. HighlightsNODDI can delineate the internal anatomy of the mouse hippocampus in vivo.Quantitative NODDI and DTI data can be collected in vivo in a single hippocampal layer.AD and MD correlate with dendritic damage in the molecular layer of EAE mice.NODDI data fail to capture dendritic damages in the molecular layer of EAE mice.DTI may be more sensitive than NODDI in detecting early changes in the hippocampal layers.

B type-Bing-Neel syndrome with MRI follow-up: a case report and review of its presentations.

Journal of Neuroradiology - In Press.Proof corrected by the author Available online since mardi 1 juillet 2014

Progressive loss of supination of the wrist

Ultrasonography showed an infiltrative lesion within the pronator quadratus, with limited mass effect (Fig. 1) without calcification or hyperhemia. Its signal intensity (SI) was low on T1 and protondensity, fat-suppressed weighted images (PD-FS-WI), suggestive of fibrous tissue. MRI showed different SI lines inside on PD-FS-WI and T1-FS-WI after gadolinium injection, in continuity with muscle, called the ‘stripe sign’ [1, 2] (Fig. 2). The lesion exhibited small peripheral edema at the periphery of its anterior side on axial and sagittal PD-FS sequences (Fig. 2b, e), with subtle enhancement but no necrotic, fatty or myxoid component. The main differential considerations for this intramuscular fibrous infiltrative tumor were desmoid type fibromatosis, nodular fasciitis and granular cell tumor. Fibroma, desmoplastic fibroma, granuloma and softt i s sue sarcomas were les s compat ib le [2 , 3] . Hypotheses were restrained by the ‘stripe sign,’ which has only been observed in granular cell tumors, proliferative myositis, myositis ossificans or sarcoidosis [2]. The patient was referred to a reference center. US guided-biopsy was performed confirming a granular cell tumor and leading to surgical excision. Gross examination showed a 3.5-cm, hard, infiltrative tumor. The specimen evidenced an epithelioid proliferation embedded in a fibrous stroma (Fig. 3a). Cells displayed a polygonal shape along with an eosinophilic granular cytoplasm pathognomonic of granular cell tumors. There was no criterion suggestive of malignancy. Cells stained for S-100 protein and CD-68, compatible with a neural origin (Fig. 3b and c). Granular cell tumors are ubiquitous tumors of neural origin, accounting for 0.5% of soft-tissue tumors [4]. Usually granular cell tumors affect 40–60-year-old women and occur in the head, neck and tongue, mainly in superficial compartments [4–6]. Among the 42 cases referenced in the database of our tertiary referral center, skin structures were affected in 23.8% of cases, head and neck in 12.9%, digestive tract in 12.5%, pelvic structures in 4.7%, breast in 7.1% and extremities in 42.9% (unpublished data). Multiple granular cell tumors occur in 10 to 20% of cases and should lead to the investigation of Noonan syndrome or neurofibromatosis type 1 [7]. According to Ramaswamy et al., among 36 cases of multiple granular cell tumors, 2 (5.6%) were The case presentation can be found at doi:10.1007/s00256-017-2721-7

Combined Cementoplasty and Percutaneous Image-Guided Screw Fixation for Treatment of Sacral Osteoradionecrosis: A Case Report

Sacral osteoradionecrosis is a pelvic radiation-induced injury. The case illustrates this complication with interventional radiology support. Combination of imaging modalities aided in diagnosis and a biopsy confirmed it. An initial sacral cementoplasty procedure was not sufficient to obtain analgesia, because necrosis continued to evolve. In order to better stabilize the weakened pelvic girdle and reduce pain, percutaneous screw fixation was performed. The patient has a favorable outcome, with reduction of pain and early rehabilitation. No infectious, hemorrhagic complication nor migration of the screws were observed at 6 months’ follow-up. Percutaneous image-guided screwing is a minimally invasive technique allowing stabilization of weakened bone and may be proposed in combination with cementoplasty in patients with sacral osteoradionecrosis.

Targeting ERBB2 mutations in solid tumors: biological and clinical implications

Preclinical data have shown that ERBB2 activating mutations are responsive to HER2 tyrosine kinase inhibitors. The aim of this study is to characterize the landscape of ERBB2 mutations in solid tumors and the potential efficacy of ERBB2 targeting.We analyzed the next-generation sequencing results from 17,878 patients with solid tumors and reported the outcome of 4 patients with advanced ERBB2-mutated tumors treated with a combination of trastuzumab and lapatinib.ERBB2 mutations occurred in 510 patients (2.85%). The tumor types with the highest incidence of ERBB2 mutations were the following: bladder (16.6%), small bowel (8.6%), ampullar (6.5%), skin non-melanoma (6.1%), and cervical cancer (5.5%). 49.4% (n = 282) were known as activating mutations. ERBB2 mutation was not mutually exclusive of ERBB2 amplification which occurred in up to 10% of cases. PI3KCA activating mutations were associated with ERBB2 mutations in 12.4% of cases mainly in breast and lung cancer. Four patients (endometrial, colorectal, cholangiocarcinoma, and adenosarcoma of the uterus) were treated with a combination of trastuzumab and lapatinib. All of them experienced tumor shrinkage resulting in stable disease in three cases and partial response in one case. One patient developed secondary resistance. Sequencing of the progressing metastasis allowed the identification of the ERBB2 L869R mutation previously associated with resistance to lapatinib in vitro.These results support further clinical investigation aiming to demonstrate that ERBB2-mutational driven therapy can improve patient care irrespective of histology.