The state of the art in beyond 5G distributed massive multiple-input multiple-output communication system solutions.

Beyond fifth generation (5G) communication systems aim towards data rates in the tera bits per second range, with improved and flexible coverage options, introducing many new technological challenges in the fields of network architecture, signal pro- cessing, and radio frequency front-ends. One option is to move towards cell-free, or distributed massive Multiple-Input Multiple-Output (MIMO) network architectures and highly integrated front-end solutions. This paper presents an outlook on be- yond 5G distributed massive MIMO communication systems, the signal processing, characterisation and simulation challenges, and an overview of the state of the art in millimetre wave antennas and electronics.

Non-traumatic pseudocyst of Glisson capsule complicating a ventriculoperitoneal shunt.

BACKGROUND: Cerebrospinal fluid pseudocysts in the peritoneal cavity following ventriculoperitoneal shunt are relatively uncommon. In these complications, perforation of solid organs is unusual. CASE DESCRIPTION: A case of subcapsular hepatic pseudocyst is described. A 48-year-old man treated by ventriculoperitoneal shunt presented with abdominal pain. Laboratory examinations revealed hepatic cytolysis. The CT-scan of the abdomen demonstrated a small ovoid non-enhanced cystic collection in the subcapsular area of hepatic segment V. Percutaneous hepatic fine-needle aspiration of the cyst guided by abdominal ultrasonography showed no abnormal findings. Peritoneal reimplantation at a different site was performed. The clinicopathological features of this entity are described and treatments are discussed. CONCLUSION: Reinsertion of the catheter at a different abdominal site is effective in non-infections cases. In contrast, a temporary external drainage with adequate antibiotic treatment followed by shunt reinsertion is necessary to treat a documented infection of CSF collections.

[Twinkling artifact on Doppler US: clinical presentations]. / L'artefact de scintillement en écho-Doppler et situations cliniques.

Twinkling artifact characterized by a rapidly fluctuating mixture of Doppler signals occurs behind a strongly reflecting granular interface such as urinary tract stones or gallstones. It may occurs in association with several clinical situations, and may sometimes be helpful for diagnosis while it may sometimes be a pitfall that must be recognized by the sonographer. After reviewing the technical nature of this artifact, several cases will be presented to illustrate the advantages and pitfalls related to this artifact.

[Hepatic Epithelioid hemangioendothelioma: a rare liver tumor]. / L'hémangioendothéliome épithélioïde du foie: une tumeur hépatique rare.

Epithelioid hemangioendothelioma of the liver is a rare primary malignant tumor of vascular origin. It most frequently occurs in middle age adults and clinical findings are non-specific. Histological diagnosis may be difficult to achieve with lesions containing a large myxoid component, and immunohistochemical staining is required. A few imaging features may suggest the correct diagnosis, and radiologists should be familiar with these findings. We will illustrate the potential role of PET-CT at the time of initial presentation. Prognosis is variable and optimal management is based on a case by case analysis, ranging from clinical and imaging follow-up to liver transplantation.

[Is power Doppler US a good predictor of prostate cancer aggressiveness]. / L'écho-Doppler puissance est-il un bon témoin de l'agressivité du cancer de la prostate?

PURPOSE: To determine the value of Power Doppler US for the diagnosis of prostate cancer and in the prediction of cancer aggressiveness. PATIENTS AND METHODS: One hundred and five consecutive patients with PSA>4 ng/ml and/or abnormal digital rectal exam underwent power Doppler US prior to biopsy. In addition to biopsies directed to suspiscious lesion on US, 10 to 12 standard sextant biopsies were obtained. Histologic results were correlated to imaging findings. RESULTS: A hypervascular lesion (enlarged, irregular, serpentine or disorganized vessels) was present at power Doppler US in 34 patients and corresponded to cancer in 28 cases. Nineteen cancers showed no detectable abnormality on power Doppler US. Cancer was present in 271 of 1093 cores. After correlation with results from sextant prostate biopsy, power Doppler showed a sensitivity of 44%, specificity of 96%, positive predictive value of 84% and negative predictive value of 80%. Positive results on power Doppler US were strongly cotrrelated with higher Gleason scores. CONCLUSION: Power Doppler US may contribute to the evaluation of prostate cancer aggressiveness and direct biopsies to more aggressive foci.