[Chyluria with "nephrotic syndrome-like" presentation: Diagnostic and therapeutic approach]. / Chylurie révélée par un « pseudo-syndrome néphrotique ¼ : démarche diagnostique et thérapeutique.

Chyluria implies an abnormal communication between the lymphatic system and the urinary tract. It is more frequent in endemic areas of lymphatic filariasis, which constitutes the main cause. Chyluria may mimic a nephrotic syndrome. Diagnosis of chyluria is based on urinary cytological and biocheminal analysis. Localization of the fistula needs medical imaging: cystoscopy, retrograde pyelography, lymphoscintigraphy and more recently magnetic resonance lymphography. Due to frequent spontaneous remissions, traitement can require only dietary measures. In case of malnutrition or clinical complications, sclerotherapy should be rapidly undertaken, before considering surgery of renal lymphatic disconnection.

Performances of preoperative CT scan to predict the pTN stage for MSI/dMMR localized colon cancers.

BACKGROUND: Neoadjuvant immunotherapy emerges as a promising strategy for patients with localized colon cancer (CC) harboring microsatellite instability/mismatch repair deficiency (MSI/dMMR). The aim of this study is to evaluate the concordance between clinical cTN stage assessed by preoperative computed tomography (CT) scan and pTN stage of MSI/dMMR CC. PATIENTS AND METHODS: Consecutive patients diagnosed for localized MSI/dMMR CC and treated with upfront surgery between 2013 and 2022 in two French centers were eligible. Two independent radiologists, blinded to pathological findings, reviewed all preoperative CT scans and assessed cTN stage, with a third radiologist reviewing discordant cases. Radiological predictive diagnostic accuracy for pT4 and pN+ (N+ = N1 or N2) were calculated. RESULTS: One hundred and thirteen patients were included (right CCs = 79%). CT scan diagnostic performances for pT4 were sensitivity (Se) = 33.3%; specificity (Sp) = 94.0%; positive predictive value (PPV) = 66.7%; and negative predictive value (NPV) = 79.6% and for pN+ were Se = 70.3%; Sp = 59.2%; PPV = 45.6%; and NPV = 80.4%. When pT-pN were combined, 37.5% of tumors identified as cT4 and/or cN+ were actually pT1-3 and pN0, and 23.1% of the pT4 and pN+ population was not identified as such radiologically. CONCLUSION: The ability of preoperative CT scan to predict pT and pN stages is limited for localized MSI/dMMR CCs. Reassessing neoadjuvant strategies' benefit-risk balance in this population is needed.

The cholangiographic features of severe forms of ABCB4/MDR3 deficiency-associated cholangiopathy in adults.

We previously reported the association of ABCB4/MDR3 gene variants with a peculiar form of cholelithiasis in European adults, currently referred to as the LPAC syndrome. ABCB4/MDR3 deficiency is also now thought to be related to some forms of hepatolithiasis in Japan. We herein report in eight patients a new phenotype associated with ABCB4 gene mutations, characterized by a typical LPAC symptomatic disease associated with large uni- or multifocal spindle-shaped dilations of the intrahepatic bile ducts without any bile duct stenosis, and filled of gallstones. We excluded from this series, the patients with minimal intrahepatic bile duct dilations, with bile duct stenosis, with focal or diffuse irregular bile ducts compatible with the diagnosis of sclerosing cholangitis, with bile duct dilations that did not contain stones or alternatively with stones in bile ducts without large dilations. The prevalence of this phenotype does not exceed 5 to 10% of the patients with LPAC syndrome. Importantly, the ABCB4/MDR3 mutations observed in this series did not differ from those observed in patients with LPAC syndrome with no or minimal intrahepatic bile duct dilations that could suggest a specific genetic background in this setting. This variant shows similar sensitivity to ursodeoxycholic acid and may be partly reversible under long-term therapy. In summary, we describe here a peculiar cholangiographic phenotype of the LPAC syndrome characterized by single-shaped large bile duct dilations filled with cholesterol or brown-pigment stones. This phenotype is not associated with a peculiar type of ABCB4 mutation.

[Diffusion-weighted MR imaging of liver pathology: principles and clinical applications]. / Imagerie par résonance magnétique de diffusion (IRMD) en pathologie hépatique: principe et applications cliniques.

Due to ongoing technological advances, the range of clinical applications for diffusion-weighted MR imaging has expanded to now include abdominal pathology. Current applications for liver pathology include two main directions. First, oncologic imaging with detection, characterization and follow-up of lesions. Second, evaluation of diffuse liver diseases, including hepatic fibrosis. The diagnostic impact and role of diffusion-weighted MR imaging remain under investigation, but appear promising. Because of its short acquisition time, sensitivity, and additional information it provides, diffusion-weighted MR imaging should be included in routine liver imaging protocols.

[Postoperative imaging after colorectal surgery]. / Imagerie post-opératoire de la chirurgie colorectale.

Surgery for the treatment of colorectal diseases has been evolving rapidly recently. In addition to classical surgical procedures (colectomy, abdominoperineal resection), new surgical procedures include coloproctectomy with creation of an ileoanal anastomosis and ileal pouch, pelvic reconstructions (omentoplasty, placement of myocutaneous flaps) and creation of different colic anastomoses after anterior rectal resection. Even if computed tomography and fluoroscopic contrast examinations are still commonly used to assess postoperative changes and complications, especially infections, pelvic magnetic resonance imaging is useful to depict postoperative changes, detect complications such as fistulas and tumor recurrence in patients who have undergone surgery for primary or recurrent rectal disease. The main surgical techniques, their respective indications and postsurgical imaging features will be discussed. The main complications and imaging work-up will also be reviewed.

Phenotypic expression of ferroportin disease in a family with the N144H mutation.

Ferroportin is a putative transmembrane channel involved in the exit of iron out of the enterocytes, the macrophages and the hepatocytes. Mutations in the human gene coding ferroportin have been linked to an unusual form of iron overload, now referred to as "hemochromatosis type IV" or "ferroportin disease" characterized by a prevalent iron overload of macrophages and liver Küpffer cells. We report four patients from a same family with ferroportin disease associated with the N144H mutation. We show that in this family the mutation which is fully penetrant, may act through an increased iron export from macrophages as suggested by the unexpected absence of iron overload in the spleen and bone marrow detected by magnetic resonance imaging, that it co-segregates with a phenotype close to the classical form of HFE-associated hemochromatosis and was associated, in the oldest patient, with the development of hepatocellular carcinoma in a non cirrhotic liver. Our findings illustrate the existence of a genotype-phenotype relationship in "ferroportin disease", suggest that MRI may be useful in determining this phenotype and show that hepatocellular carcinoma may occur in these patients even without cirrhosis. This observation justifies careful follow-up of this subgroup of patients.

[Imaging of incidental cystic lesions of the pancreas]. / Imagerie des lésions kystiques du pancréas de découverte fortuite.

Cystic lesions of the pancreas, with an estimated prevalence of 20%, frequently are incidental findings at imaging on asymptomatic patients. Pseudocysts, typically in a setting of pancreatitis, should first be excluded. Characterization of cystic tumors is more complicated. Still, it is important to differentiate between benign and malignant lesions. Multi-detector row CT and MRI allow characterization of such lesions in over 75% of cases. Indeterminate lesions should undergo endoscopic US with biopsy/aspiration and fluid analysis, especially for mucin producing tumors (rounded with thick enhancing wall). When imaging fails to fully characterize a lesion, follow-up may be proposed for lesions less than 3 cm in size, that are either unilocular with thin nonenhancing wall (simple cyst) or lobulated multilocular with thin nonenhancing wall (serous cystadenoma, isolated side branch IPMTP). Follow-up imaging shows that these tumors usually show very little change over time. Management is based on comparing estimated patient survival without treatment to surgical risks (morbidity, mortality, functional sequelae from the procedure).

MR lymphography of abdominal and retroperitoneal lymphatic vessels.

OBJECTIVE: The abdominal and retroperitoneal lymphatic system is characterized by numerous anatomic variations. Our objective is to review MR lymphographic features of normal anatomy and abnormal conditions. CONCLUSION: MR lymphography is a noninvasive technique that is well suited for the examination of abdominal and retroperitoneal lymphatic vessels.

[Imaging of thoracic pathology in patients with AIDS]. / Imagerie des pathologies thoraciques chez le patient VIH au stade sida.

The imaging features of infectious and non-infectious pathologies in HIV patients with AIDS (less than 200 CD4/mm3) are illustrated. Opportunistic infections, tumors and vascular pathologies have variable appearances based on the degree of immunosuppression and patient compliance with opportunistic infection prophylaxis. Because of advances in retroviral treatments and wider use of anti-infectious prophylaxis, thoracic pathologies in AIDS patients are less frequent but must nonetheless be recognized, and diagnosis should be suggested in patients with unknown serologic status.

[Pineapple juice as a negative oral contrast agent in magnetic resonance cholangiopancreatography]. / Utilisation du jus d'ananas en tant qu'agent de contraste négatif en cholangiopancréatographie par résonance magnétique*

PURPOSE: The quality of magnetic resonance cholangiopancreatography (MRCP) images is frequently degraded by high signal from the gastrointestinal tract on heavily T2W images. The purpose of this study is to evaluate pineapple juice (PJ) as an oral negative contrast agent in MRCP. MATERIALS AND METHODS: Results from MRCP in 50 patients with PJ and 50 patients with paramagnetic contrast (ferumoxsil-Lumirem) were compared. Reviewers were blinded to the type of contrast agent. Exam quality was recorded with regards to signal suppression in the stomach, duodenum and proximal small bowel and with regards to pancreatic duct and biliary ducts visualization. In vitro, the signal characteristics of several commercially available brands of PJ were assessed using T1W, T2W and MRCP sequences. Signal intensity was correlated with the manganese concentration measured using atomic absorption spectrometry. Finally, the reviewers compared the taste of PJ and ferumoxsil. RESULTS: On MRCP sequences, results were similar with regards to signal suppression in the stomach, duodenum and proximal small bowel with PJ and ferumoxsil. Visualization of the pancreatic duct, intrahgepatic bile ducts and CBD was similar with PJ and ferumoxsil. The signal intensity of commercially available brands of PJ on T2W and MRCP sequences correlated well with the measured manganese concentration on spectroscopy. Variations in manganese concentration were observed, with values ranging from 3.65 to 27.24 mg/L. The reviewers noted that PJ tasted "good" or "very good" and that ferumoxsil tasted "bad" or "very bad". CONCLUSION: Ingestion of PJ provides effective signal suppression in the GI tract on MRCP, similar to paramagnetic contrast agents. Because manganese concentration is highly variable in commercially available PJ brands, a brand with high manganese concentration should be selected.

[Vasculitis of the hepatic artery: A case of a single-organ vasculitis]. / Vascularite de l'artère hépatique : à propos d'un cas d'atteinte d'organe isolée.

INTRODUCTION: Vasculitis usually have a systemic involvement. Rare cases of localized vasculitis have been described, but the exclusive involvement of the hepatic artery is exceptional. We report the case of a patient who developed a vasculitis of the right and left hepatic arteries. CASE REPORT: A 63-year-old woman presented with unexplained abdominal pain. A computed tomography of the abdomen was suggestive of vasculitis of the hepatic arteries, showing a sequence of stenosis and aneurysmal dilatations of the hepatic arteries. There were no other arterial involvement, in particular of the abdomen and the brain. No other systemic disease or infection was found. The outcome was favorable, with corticosteroids alone. DISCUSSION: The exclusive involvement of the hepatic artery is an exceptional form of localized vasculitis, with only one other case reported. This diagnosis could therefore be discussed, in the presence of unexplained hepatic hematoma or pain.

[Solitary fibrous tumor of the liver]. / Tumeur fibreuse solitaire du foie.

Solitary fibrous tumor (SFT) is commonly found on serosal surfaces, and is rarely localized in the liver. There are benign and malignant variants of hepatic SFT. We report a new case of benign SFT. Our patient, a 63-year old woman, who has been followed for 5 years for an asymptomatic liver mass, was admitted for abdominal pain. Ultrasonography (US), CT, MR Imaging and angiography showed the liver mass with typical imaging features, situated in the right hepatic lobe with blood supply from the hepatic artery. Histopathological examination demonstrated a highly vascularized tumor, composed of short spindle cells alternating with hypocellular collagenous regions, with a hemangiopericytoma-like vascular pattern. The immunohistochemical staining was positive for CD 34. Tumor resection was performed. Follow-up 8 years after the resection showed no tumor recurrence or metastasis, thus confirming the initial diagnosis of benign SFT.

[External phased-array MR imaging preoperative assessment of rectal cancer]. / Bilan pré opératoire des cancers du rectum en IRM pelvienne haute résolution avec antenne en réseau phasé.

The main problem associated with rectal cancer treatment is tumor recurrence. Randomized controlled studies have shown that adjuvant preoperative radiation therapy is effective for reducing local recurrence. These studies have also demonstrated that there are groups of rectal cancer patients with differing degrees of risk for local recurrence. At one end of the spectrum is the low-risk group: patients with superficial rectal cancer, who can be treated with surgery alone. At the other end is the high-risk group: patients with a close or involved resection margin at total mesorectal excision, the very advanced tumors that require a longer course of chemotherapy and radiation therapy, and extensive surgery. Paramount for this selection and differentiated treatment is a reliable preoperative test that can be used to distinguish these groups of patients. In this review article, we will discuss the role of high-resolution phased array MRI among the other imaging modalities such as endorectal MRI, endorectal US, and CT. We will also discuss and illustrate MR imaging results in terms of T stage, circumferential resection margin, locally advanced rectal cancer, and N stage.