Advanced multiparametric magnetic resonance imaging of multinodular and vacuolating neuronal tumor.

BACKGROUND AND PURPOSE: Multinodular and vacuolating neuronal tumor (MVNT) of the cerebrum is a rare brain lesion with suggestive imaging features. The aim of our study was to report the largest series of MVNTs so far and to evaluate the utility of advanced multiparametric magnetic resonance (MR) techniques. METHODS: This multicenter retrospective study was approved by our institutional research ethics board. From July 2014 to May 2019, two radiologists read in consensus the MR examinations of patients presenting with a lesion suggestive of an MVNT. They analyzed the lesions' MR characteristics on structural images and advanced multiparametric MR imaging. RESULTS: A total of 64 patients (29 women and 35 men, mean age 44.2 ± 15.1 years) from 25 centers were included. Lesions were all hyperintense on fluid-attenuated inversion recovery and T2-weighted imaging without post-contrast enhancement. The median relative apparent diffusion coefficient on diffusion-weighted imaging was 1.13 [interquartile range (IQR), 0.2]. Perfusion-weighted imaging showed no increase in perfusion, with a relative cerebral blood volume of 1.02 (IQR, 0.05) and a relative cerebral blood flow of 1.01 (IQR, 0.08). MR spectroscopy showed no abnormal peaks. Median follow-up was 2 (IQR, 1.2) years, without any changes in size. CONCLUSIONS: A comprehensive characterization protocol including advanced multiparametric magnetic resonance imaging sequences showed no imaging patterns suggestive of malignancy in MVNTs. It might be useful to better characterize MVNTs.

Combining Multiple Magnetic Resonance Imaging Sequences Provides Independent Reproducible Radiomics Features.

To evaluate the relative contribution of different Magnetic Resonance Imaging (MRI) sequences for the extraction of radiomics features in a cohort of patients with lacrimal gland tumors. This prospective study was approved by the Institutional Review Board and signed informed consent was obtained from all participants. From December 2015 to April 2017, 37 patients with lacrimal gland lesions underwent MRI before surgery, including axial T1-WI, axial Diffusion-WI, coronal DIXON-T2-WI and coronal post-contrast DIXON-T1-WI. Two readers manually delineated both lacrimal glands to assess inter-observer reproducibility, and one reader performed two successive delineations to assess intra-observer reproducibility. Radiomics features were extracted using an in-house software to calculate 85 features per region-of-interest (510 features/patient). Reproducible features were defined as features presenting both an intra-class correlation coefficient ≥0.8 and a concordance correlation coefficient ≥0.9 across combinations of the three delineations. Among these features, the ones yielding redundant information were identified as clusters using hierarchical clustering based on the Spearman correlation coefficient. All the MR sequences provided reproducible radiomics features (range 14(16%)-37(44%)) and non-redundant clusters (range 5-14). The highest numbers of features and clusters were provided by the water and in-phase DIXON T2-WI and water and in-phase post-contrast DIXON T1-WI (37, 26, 26 and 26 features and 14,12, 9 and 11 clusters, respectively). A total of 145 reproducible features grouped into 51 independent clusters was provided by pooling all the MR sequences. All MRI sequences provided reproducible radiomics features yielding independent information which could potentially serve as biomarkers.

Multinodular and Vacuolating Posterior Fossa Lesions of Unknown Significance.

Multinodular and vacuolating neuronal tumor of the cerebrum is a rare supratentorial brain tumor described for the first time in 2013. Here, we report 11 cases of infratentorial lesions showing similar striking imaging features consisting of a cluster of low T1-weighted imaging and high T2-FLAIR signal intensity nodules, which we referred to as multinodular and vacuolating posterior fossa lesions of unknown significance. No relationship was found between the location of the lesion and clinical symptoms. A T2-FLAIR hypointense central dot sign was present in images of 9/11 (82%) patients. Cortical involvement was present in 2/11 (18%) of patients. Only 1 nodule of 1 multinodular and vacuolating posterior fossa lesion of unknown significance showed enhancement on postcontrast T1WI. DWI, SWI, MRS, and PWI showed no malignant pattern. Lesions did not change in size or signal during a median follow-up of 3 years, suggesting that multinodular and vacuolating posterior fossa lesions of unknown significance are benign malformative lesions that do not require surgical intervention or removal.

Improved Detection of New MS Lesions during Follow-Up Using an Automated MR Coregistration-Fusion Method.

BACKGROUND AND PURPOSE: MR imaging is the key examination in the follow-up of patients with MS, by identification of new high-signal T2 brain lesions. However, identifying new lesions when scrolling through 2 follow-up MR images can be difficult and time-consuming. Our aim was to compare an automated coregistration-fusion reading approach with the standard approach by identifying new high-signal T2 brain lesions in patients with multiple sclerosis during follow-up MR imaging. MATERIALS AND METHODS: This prospective monocenter study included 94 patients (mean age, 38.9 years) treated for MS with dimethyl fumarate from January 2014 to August 2016. One senior neuroradiologist and 1 junior radiologist checked for new high-signal T2 brain lesions, independently analyzing blinded image datasets with automated coregistration-fusion or the standard scroll-through approach with a 3-week delay between the 2 readings. A consensus reading with a second senior neuroradiologist served as a criterion standard for analyses. A Poisson regression and logistic and γ regressions were used to compare the 2 methods. Intra- and interobserver agreement was assessed by the κ coefficient. RESULTS: There were significantly more new high-signal T2 lesions per patient detected with the coregistration-fusion method (7 versus 4, P < .001). The coregistration-fusion method detected significantly more patients with at least 1 new high-signal T2 lesion (59% versus 46%, P = .02) and was associated with significantly faster overall reading time (86 seconds faster, P < .001) and higher reader confidence (91% versus 40%, P < 1 × 10-4). Inter- and intraobserver agreement was excellent for counting new high-signal T2 lesions. CONCLUSIONS: Our study showed that an automated coregistration-fusion method was more sensitive for detecting new high-signal T2 lesions in patients with MS and reducing reading time. This method could help to improve follow-up care.

[Idiopathic and secondary capillary leak syndromes: A systematic review of the literature]. / Syndrome de fuite capillaire idiopathique et formes secondaires : une revue systématique de la littérature.

PURPOSE: The capillary leak syndrome (CLS) is a rare condition characterized by the onset of hypotension, edema, hemoconcentration and hypoalbuminemia. CLS can be idiopathic (Clarkson's disease) or secondary to various conditions and treatments. Here, we review the clinical and biological features, pathophysiology, causes and treatment of this rare condition. METHODS: We performed a systematic review of the literature (Medline database through February 2014) to identify all articles about CLS. The relevant references were selected by two independent authors. RESULTS: Secondary CLSs are mostly due to malignant hematological diseases, viral infections, and treatments such as chemotherapies and therapeutic growth factors. Diagnosis of idiopathic CLS is made by exclusion of secondary diseases, especially as a serum monoclonal immunoglobulin is present, or when there is a relapsing disease, no initial lung involvement or preserved consciousness despite low blood pressure. Acute episodes are treated with vasopressor therapy and judicious fluid replacement. Between episodes, patients with Clarkson's disease may be treated with intravenous immunoglobulins. CLS is a severe disease with significantly impaired prognosis. CONCLUSION: Clarification of the pathophysiological mechanisms of CLS is essential to improve the prognosis of this rare disease with more targeted treatments.

Clinical application of amniotic membranes on a patient with epidermolysis bullosa.

The case of a patient with dystrophic epidermolysis bullosa treated with radiosterilised amniotic membranes is presented. The disorder is a congenital disease characterised by a poor desmosomal junction in the keratinocyte membrane. After proper donor screening, amnios were collected at Hospital Central Sur de Alta Especialidad (HCSAE), PEMEX and microbiological analysis was performed at Universidad Nacional Autónoma de México, FQUNAM, (Biology Dept. of the Chemistry Faculty, National Autonomous University of Mexico), before and after radiation sterilisation. Processing, packaging and sterilisation were performed at Instituto Nacional de Investigaciones Nucleares, ININ, (National Nuclear Research Institute). The patient, a ten-year-old boy with severe malnutrition, extensive loss of skin and pseudomonad infection in the whole body, was treated with gentle debridement in a Hubbard bath. Later amnion application was performed with sterilised amnios by using two different processes, in one of which the amnion was sterilised with paracetic acid, preserved in glycerol, kindly donated by the German Institute for Tissue and Cell Replacement and applied by Dr. Johannes C. Bruck, IAEA visiting expert, and the other amnion was processed at ININ: air dried and sterilised by gamma radiation at dose of 30 kGy. After spontaneous epithelisation was successfully promoted for seven days, the pain was alleviated and mobility was improved in a few hours and the patient's general condition was so improved that in a month he was discharged. Unfortunately, because this disease is revertive and has malignant degeneration, the prognosis is not good.

Application of acellular dermis and autograft on burns and scars.

The cases of two patients with burns treated with dermis allograft and of one patient for lip reconstructive aesthetic filling treated with less than one mm3 of radiosterilised acellular dermis are presented. This paper emphasizes the treatment with radiosterilised dermal grafts with a permanent character so far. Hospitals, therefore, can satisfy the demand for this kind of tissue in the case of disaster and patients with serious injuries. In the cases cited, histocompatibility analysis was not required, thus having the advantage of long-time storage of the radiosterilised dermis used on these patients. Neither inflammatory reaction nor acute phase re-absorption were observed. Moreover, shrink (contract) healing was diminished. After two years, the results are still satisfactory.

The clinical application of a fetal membrane on a diabetic patient's injury.

A description of the successful use of a fetal membrane in the recovery of a injured patient is presented. A diabetic female patient, 63 years old, was accidentally injured with a winnowing fork, which opened the skin of the front side of her left foot. For first two weeks, she was submitted to a treatment involving antibiotics, analgesics and antiinflammatories, but the infection did not disappear and the pain was almost unbearable. At the end of the third week, the injury underwent surgical washing with epidural blockage; suitable insulin dose and oral antidiabetics controlled the high-glucose concentration. However, due to the intensity of the pain, a risky epidural blockage was administered every four hours for 12 days. Finally, a radiosterilised human fetal membrane, which was collected at HCSAE and processed at ININ, was used as a biological wound dressing. Biological control of the tissue was performed at Facultad de Química de la Universidad Nacional Autónoma de México (The Chemistry Faculty of the National Autonomous University of Mexico) (UNAM). As a result, the pain first diminished and then stopped. The healing process started in a few days and led to a complete recovery in 2 1/2 months. At present, the patient is in good condition, living a normal life.