Current use of MRI in patients with liver metastatic colorectal cancer: a population-based study.

BACKGROUND: Liver MRI is recommended as the preoperative imaging strategy in liver metastatic colorectal cancers. OBJECTIVE: The aim of the study was to assess for the first time the use of liver MRI in a French population-based cancer registry. PATIENTS AND METHODS: All liver-only metastatic colorectal cancers resected for their primary tumour diagnosed between 2009 and 2013 were included. Nonconditional logistic regression was used to search for associations between the MRI order and the characteristics of patients and tumours. RESULTS: The primary tumour and liver metastases were resected for cure in 30% (69/233) of cases, and in 72% of these liver MRI was performed before resection of the liver metastases. Preoperative MRI ordering was not significantly higher in patients younger than 70 years when compared with that in older patients. Among patients who did not undergo resection of their liver metastasis, 22% had undergone a liver MRI. After adjustment for comorbidities, the probability of having undergone an MRI was higher for patients managed in the university hospital (P=0.004) and lower in those managed in nonuniversity hospitals (P=0.002) compared with the mean of odds for all facilities. Patients more than or equal to 70 years were 2.4 times less likely than younger patients to undergo an MRI (P=0.043). CONCLUSION: Liver MRI was underused in patients with colorectal liver-only synchronous metastasis undergoing curative resection for metastases and in elderly patients.

Microbiome profiling of drinking water in relation to incidence of inflammatory bowel disease.

The etiology of inflammatory bowel disease (IBD) is unknown; current research is focused on determining environmental factors. One consideration is drinking water: water systems harbour considerable microbial diversity, with bacterial concentrations estimated at 10(6)-10(8) cells/L. Perhaps differences in microbial ecology of water sources may impact differential incidence rates of IBD. Regions of Manitoba were geographically mapped according to incidence rates of IBD and identified as high (HIA) or low (LIA) incidence areas. Bulk water, filter material, and pipe wall samples were collected from public buildings in different jurisdictions and their population structure analyzed using 16S rDNA sequencing. At the phylum level, Proteobacteria were observed significantly less frequently (P = 0.02) in HIA versus LIA. The abundance of Proteobacteria was also found to vary according to water treatment distribution networks. Gammaproteobacteria was the most abundant class of bacteria and was observed more frequently (P = 0.006) in LIA. At the genus level, microbes found to associate with HIA include Bradyrhizobium (P = 0.02) and Pseudomonas (P = 0.02). Particular microbes were found to associate with LIA or HIA, based on sample location and (or) type. This work lays out a basis for further studies exploring water as a potential environmental source for IBD triggers.

The Features of Fecal and Ileal Mucosa-Associated Microbiota in Dairy Calves during Early Infection with Mycobacterium avium Subspecies paratuberculosis.

Current diagnostic tests for Johne's disease (JD), a chronic granulomatous inflammation of the gastrointestinal tract of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP), lack the sensitivity to identify infected animals at early (asymptomatic) stages of the disease. The objective was to determine the pattern of MAP-associated dysbiosis of intestinal microbiota as a potential biomarker for early detection of infected cattle. To that end, genomic DNA was extracted from ileal mucosa and fecal samples collected from 28 MAP-positive and five control calves. High-throughput Illumina sequencing of the V4 hypervariable region of the 16S rRNA gene was used for community profiling of ileal mucosa-associated (MAM) or fecal microbiota. The PERMANOVA analysis of unweighted UniFrac distances revealed distinct clustering of ileal MAM (P = 0.049) and fecal microbiota (P = 0.068) in MAP-infected vs. control cattle. Microbiota profile of MAP-infected animals was further investigated by linear discriminant analysis effective size (LEfSe); several bacterial taxa within the phylum Proteobacteria were overrepresented in ileal MAM of control calves. Moreover, based on reconstructed metagenomes (PICRUSt) of ileal MAM, functional pathways associated with MAP infection were inferred. Enrichment of lysine and histidine metabolism pathways, and underrepresentation of glutathione metabolism and leucine and isoleucine degradation pathways in MAP-infected calves suggested potential contributions of ileal MAM in development of intestinal inflammation. Finally, simultaneous overrepresentation of families Planococcaceae and Paraprevotellaceae, as well as underrepresentation of genera Faecalibacterium and Akkermansia in the fecal microbiota of infected cattle, served as potential biomarker for identifying infected cattle during subclinical stages of JD. Collectively, based on compositional and functional shifts in intestinal microbiota of infected cattle, we inferred that this dynamic network of microorganisms had an active role in intestinal homeostasis.

Genome-based Definition of an Inflammatory Bowel Disease-associated Adherent-Invasive Escherichia coli Pathovar.

BACKGROUND: Mucosal-associated Escherichia coli are commonly found in inflamed tissues during inflammatory bowel disease (IBD). These bacteria often possess an adherent and invasive phenotype but lack virulence-associated features of well-described intestinal E. coli pathogens, and are of diverse serology and phylotypes, making it difficult to correlate strain characteristics with exacerbations of disease. METHODS: The genome sequences of 14 phenotypically assigned adherent-invasive Escherichia coli (AIEC) isolates obtained from intestinal biopsies of patients with IBD were compared with the genome sequences of 37 other pathogenic and commensal E. coli available from public databases. RESULTS: Core genome-based phylogenetic analyses and genome-wide comparison of genetic content established the existence of a closely related cluster of AIEC strains with 3 distinct genetic insertions differentiating them from commensal E. coli. These strains are of the B2 phylotype have a variant type VI secretion system (T6SS-1), and are highly related to extraintestinal pathogenic E. coli, suggesting that these 2 clinically distinct pathovars have common virulence strategies. Four other mucosally adherent E. coli strains from patients with IBD were of diverse phylogenetic origins and lacked the 3 genetic features, suggesting that they are not related to the B2 AIEC cluster. Although AIEC are often considered as having a unique association with Crohn's disease, isolates from Crohn's disease and ulcerative colitis were genetically indistinguishable. CONCLUSIONS: B2 AIEC thus represent a closely related cluster of IBD-associated E. coli strains that are distinct from normal commensal isolates, and which should be considered separately from the phenotypically similar but genetically distinct non-B2 AIEC strains when considering their association with intestinal pathogenesis.

Image-guided percutaneous microwave ablation of small renal tumours: short- and mid-term outcomes.

BACKGROUND: The purpose is to assess the short- and mid-term outcomes of microwave ablation (MWA) of small renal tumours in selected patients. METHODS: From August 2012 to February 2015, 29 renal tumours in 23 patients (17 male, 6 female, mean age 75 years) were treated by percutaneous MWA under imaging guidance. The tumours were 1-4.7 cm in diameter (mean size, 2.7 cm). Therapeutic effects were assessed at follow-up with magnetic resonance imaging (MRI). All patients were followed up for 2-25 months (mean, 12.2 months) to observe the therapeutic effects and complications. Changes in renal function at day 1 after treatment were statistically analyzed using the Student paired t-test or the paired Wilcoxon test. RESULTS: Technical success was achieved in all cases. One severe bleeding complication post-procedure occurred leading to death. No other unexpected side effects were observed after the MWA procedures. Clinical effectiveness was 100%. None of the patients showed recurrence on MRI imaging follow-up. No significant changes in renal function were noted after treatment (P=0.57). CONCLUSIONS: Our preliminary study demonstrates that the use of MWA for the treatment of small renal tumours can be applied as safely and efficiently as other ablative techniques in selected patients not eligible for surgery.

Preoperative portal vein embolization in liver cancer: indications, techniques and outcomes.

Postoperative liver failure is a severe complication of major hepatectomies, in particular in patients with a chronic underlying liver disease. Portal vein embolization (PVE) is an approach that is gaining increasing acceptance in the preoperative treatment of selected patients prior to major hepatic resection. Induction of selective hypertrophy of the non-diseased portion of the liver with PVE in patients with either primary or secondary hepatobiliary, malignancy with small estimated future liver remnants (FLR) may result in fewer complications and shorter hospital stays following resection. Additionally, PVE performed in patients initially considered unsuitable for resection due to lack of sufficient remaining normal parenchyma may add to the pool of candidates for surgical treatment. A thorough knowledge of hepatic segmentation and portal venous anatomy is essential before performing PVE. In addition, the indications and contraindications for PVE, the methods for assessing hepatic lobar hypertrophy, the means of determining optimal timing of resection, and the possible complications of PVE need to be fully understood before undertaking the procedure. Technique may vary among operators, but cyanoacrylate glue seems to be the best embolic agent with the highest expected rate of liver regeneration for PVE. The procedure is usually indicated when the remnant liver accounts for less than 25-40% of the total liver volume. Compensatory hypertrophy of the non-embolized segments is maximal during the first 2 weeks and persists, although to a lesser extent during approximately 6 weeks. Liver resection is performed 2 to 6 weeks after embolization. The goal of this article is to discuss the rationale, indications, techniques and outcomes of PVE before major hepatectomy.

Endovascular management of visceral artery aneurysms: When to watch, when to intervene?

Visceral artery aneurysms (VAA) include splanchnic and renal artery aneurysms. They represent a rare clinical entity, although their detection is rising due to an increased use of cross-sectional imaging. Rupture is the most devastating complication, and is associated with a high morbidity and mortality. In addition, increased percutaneous endovascular interventions have raised the incidence of iatrogenic visceral artery pseudoaneurysms (VAPAs). For this reason, elective repair is preferable in the appropriately chosen patient. Controversy still exists regarding their treatment. Over the past decade, there has been steady increase in the utilization of minimally invasive, non-operative interventions, for vascular aneurysmal disease. All VAAs and VAPAs can technically be fixed by endovascular techniques but that does not mean they should. These catheter-based techniques constitute an excellent approach in the elective setting. However, in the emergent setting it may carry a higher morbidity and mortality. The decision for intervention has to take into account the size and the natural history of the lesion, the risk of rupture, which is high during pregnancy, and the relative risk of surgical or radiological intervention. For splanchnic artery aneurysms, we should recognize that we are not, in reality, well informed about their natural history. For most asymptomatic aneurysms, expectant treatment is acceptable. For large, symptomatic or aneurysms with a high risk of rupture, endovascular treatment has become the first-line therapy. Treatment of VAPAs is always mandatory because of the high risk of rupture. We present our point of view on interventional radiology in the splanchnic arteries, focusing on what has been achieved and the remaining challenges.

MR Angiography at 3 T of Peripheral Arterial Disease: A Randomized Prospective Comparison of Gadoterate Meglumine and Gadobutrol.

OBJECTIVE: This large-scale randomized study aimed to show the noninferiority in terms of diagnostic performance of gadoterate meglumine-enhanced versus gadobutrol-enhanced 3-T MR angiography (MRA) using digital subtraction angiography (DSA) as the reference standard in patients with peripheral arterial occlusive disease (PAOD). SUBJECTS AND METHODS: In this prospective international randomized double-blind phase IV trial, 189 patients were enrolled. Of them, 156 could be included in the per-protocol population for on-site assessments and 154 for off-site readings. Subjects underwent peripheral MRA, after injection of 0.1 mmol/kg of either gadoterate meglumine or gadobutrol, and DSA within 30 days. The diagnostic accuracy was evaluated and compared using a noninferiority analysis. Secondary endpoints included sensitivity, specificity, diagnostic confidence, contrast-to-noise ratio, and signal-to-noise ratio evaluations. RESULTS: The percentage agreement between MRA and DSA for stenosis detection was similar for on-site readings for both groups (mean ± SD, 80.6% ± 16.1% with gadoterate meglumine vs 77.1% ± 19.6% with gadobutrol; 3.5% difference), and the same was true for off-site readings (73.9% ± 16.9% with gadoterate meglumine vs 75.1% ± 13.8% with gadobutrol; 1.1% difference). The noninferiority of gadoterate meglumine to gadobutrol was shown for both on- and off-site readings. Sensitivity in detecting significant stenosis (> 50%) was 72.3% for gadoterate meglumine versus 70.6% for gadobutrol, whereas specificity (92.6% vs 92.3%), diagnostic confidence (87.0% vs 86.0%), signal-to-noise ratio (165.5 vs 161.0), and contrast-to-noise ratio (159.5 vs 155.3) did not differ statistically significantly between the two groups. CONCLUSION: Gadoterate meglumine was found to be not inferior to gadobutrol in terms of diagnostic performance in patients with PAOD undergoing 3-T contrast-enhanced MRA. No statistically significant differences were detected between the two MRA groups.

Cervical foraminal steroid injections under CT guidance: retrospective study of in situ contrast aspects in a serial of 248 cases.

OBJECTIVES: To describe all the CT findings after in situ contrast injection just before steroid injection and to recognize the abnormal aspects associated with intravascular contamination. MATERIAL AND METHODS: We retrospectively evaluated 248 cervical transforaminal steroid injections done at the university hospital in Dijon, France, in 2008-2012, to treat cervicobrachial neuralgia inadequately improved by optimal medical treatment for at least 3 weeks. Features describing the opacification patterns were recorded. RESULTS: Five main nonvascular opacification patterns were identified: clumps of contrast agent outside the foramen (16 %), a crab claw pattern surrounding the ganglion (13 %), a "French" circumflex accent pattern (15 %), reflux along the needle (7 %), and facet joint capsule opacification (22 %). Concerning the situations requiring a change in needle position, intravenous injection occurred in 26 % of the patients, with a crab claw pattern in half the cases and a clump pattern in half the cases. Intraarteriolar injection was noted in two patients. CONCLUSION: CT after in situ contrast injection ensures proper needle positioning outside the blood vessels before steroid injection. Penetration of the needle tip into a vein is very common, whereas arteriolar puncture is extremely rare.

Role of the BaeSR two-component regulatory system in resistance of Escherichia coli O157:H7 to allyl isothiocyanate.

Allyl isothiocyanate (AITC) is an essential oil with antimicrobial activity against Escherichia coli O157:H7. The ability of E. coli O157:H7 to withstand inhibitory AITC concentrations and the role of the two-component BaeSR system as a defense mechanism against AITC was studied. Optimal conditions for AITC stability in an aqueous medium were 25 °C and pH 5. The minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations of AITC against wild-type E. coli O157:H7 were 51 and 412 ppm, respectively. After growing E. coli O157:H7 in stepwise increased concentrations of AITC, the strain withstood concentrations beyond its MIC (206 ppm), but resistance was reversed when AITC exposure was interrupted. Deletion of either the sensor or regulator genes, baeS or baeR, yielded cells only as resistant as the wild-type, but the complete deletion of the BaeSR system decreased AITC resistance of E. coli O157:H7 to half that of wild-type cells. This is the first demonstration that the ability of E. coli O157:H7 to withstand AITC challenge is compromised by the deletion of the BaeSR system. It also indicates that temporary adaptive bacterial resistance to repeated incremental AITC exposure may occur, but it is unlikely to restrict the importance of AITC as an antimicrobial against E. coli O157:H7.

Characterization of the gut-associated microbiome in inflammatory pouch complications following ileal pouch-anal anastomosis.

INTRODUCTION: Inflammatory complications following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) are common and thought to arise through mechanisms similar to de novo onset inflammatory bowel disease. The aim of this study was to determine whether specific organisms in the tissue-associated microbiota are associated with inflammatory pouch complications. METHODS: Patients having previously undergone IPAA were recruited from Mount Sinai Hospital. Clinical and demographic information were collected and a pouchoscopy with biopsy of both the pouch and afferent limb was performed. Patients were classified based on post-surgical phenotype into four outcome groups: familial adenomatous polyposis controls (FAP), no pouchitis, pouchitis, and Crohn's disease-like (CDL). Pyrosequencing of the 16S rRNA V1-V3 hypervariable region, and quantitative PCR for bacteria of interest, were used to identify organisms present in the afferent limb and pouch. Associations with outcomes were evaluated using exact and non-parametric tests of significance. RESULTS: Analysis at the phylum level indicated that Bacteroidetes were detected significantly less frequently (P<0.0001) in the inflammatory outcome groups (pouchitis and CDL) compared to both FAP and no pouchitis. Conversely, Proteobacteria were detected more frequently in the inflammatory groups (P=0.01). At the genus level, organisms associated with outcome were detected less frequently among the inflammatory groups compared to those without inflammation. Several of these organisms, including Bacteroides (P<0.0001), Parabacteroides (P≤2.2x10(-3)), Blautia (P≤3.0x10(-3)) and Sutterella (P≤2.5x10(-3)), were associated with outcome in both the pouch and afferent limb. These associations remained significant even following adjustment for antibiotic use, smoking, country of birth and gender. Individuals with quiescent disease receiving antibiotic therapy displayed similar reductions in these organisms as those with active pouch inflammation. CONCLUSIONS: Specific genera are associated with inflammation of the ileal pouch, with a reduction of typically ubiquitous organisms characterizing the inflammatory phenotypes.

Transjugular intrahepatic portosystemic shunt for the management of acute variceal hemorrhage.

Acute variceal hemorrhage, a life-threatening condition that requires a multidisciplinary approach for effective therapy, is defined as visible bleeding from an esophageal or gastric varix at the time of endoscopy, the presence of large esophageal varices with recent stigmata of bleeding, or fresh blood visible in the stomach with no other source of bleeding identified. Transfusion of blood products, pharmacological treatments and early endoscopic therapy are often effective; however, if primary hemostasis cannot be obtained or if uncontrollable early rebleeding occurs, transjugular intrahepatic portosystemic shunt (TIPS) is recommended as rescue treatment. The TIPS represents a major advance in the treatment of complications of portal hypertension. Acute variceal hemorrhage that is poorly controlled with endoscopic therapy is generally well controlled with TIPS, which has a 90% to 100% success rate. However, TIPS is associated with a mortality of 30% to 50% in such a setting. Emergency TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy failure, before the clinical condition worsens. Furthermore, admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized effectively. This review article discusses initial management and then focuses on the specific role of TIPS as a primary therapy to control acute variceal hemorrhage, particularly as a rescue therapy following failure of endoscopic approaches.

Antimicrobial resistance of Enterococcus species from meat and fermented meat products isolated by a PCR-based rapid screening method.

Enterococci are predominantly found in the gastrointestinal tract of humans and animals, but species commonly resident on vegetation are known. Their presence in large numbers in foods may indicate a lapse in sanitation and their ability to serve as a genetic reservoir of transferable antibiotic resistance is of concern. Conventional culture methods for identification of enterococci are slow and sometimes give false results because of the biochemical diversity of the organisms in this genus. This work reports the development of a PCR-based assay to detect enterococci at the genus level by targeting a 16S rRNA sequence. Published 16S rRNA sequences were aligned and used to design genus specific primers (EntF and EntR). The primers were able to amplify a 678 bp target region from Enterococcus faecalis ATCC 7080 and 20 other strains of enterococci from 11 different species, but there was no amplification by 32 species from closely related genera (Pediococcus, Lactobacillus, Streptococcus and Listeria) or species of Escherichia coli and Salmonella. The PCR positive samples were plated, screened by a colony patch technique and their identities were confirmed by API 20 Strep panels and sequencing. When dry fermented sausage and ham as well as fresh meat batter for dry cured sausage manufacture were tested for enterococci by the method, 29 Enterococcus strains (15 E. faecalis, 13 E. faecium, and one E. gallinarum) were identified. When susceptibility of these enterococci to 12 antibiotics was tested, the highest incidence of resistance was to clindamycin (89.6%), followed by tetracycline hydrochloride (65.5%), tylosin (62%), erythromycin (45%), streptomycin and neomycin (17%), chloramphenicol (10.3%), penicillin (10.3%), ciprofloxacin (10.3%) and gentamicin (3.4%). None was resistant to the clinically important drugs vancomycin or ampicillin. Most strains (27/29) were resistant to more than one antibiotic while 17 of 29 strains were resistant to three to 8 antibiotics. The molecular method developed was validated for speciation of enterococci and was useful in assessing uncooked processed meat products as a reservoir for multi-drug resistant Enterococcus species.

Assessing the inactivation of Mycobacterium avium subsp. paratuberculosis during composting of livestock carcasses.

Mycobacterium avium subsp. paratuberculosis causes Johne's disease (JD) in ruminants, with substantial economic impacts on the cattle industry. Johne's disease is known for its long latency period, and difficulties in diagnosis are due to insensitivities of current detection methods. Eradication is challenging as M. avium subsp. paratuberculosis can survive for extended periods within the environment, resulting in new infections in naïve animals (W. Xu et al., J. Environ. Qual. 38:437-450, 2009). This study explored the use of a biosecure, static composting structure to inactivate M. avium subsp. paratuberculosis. Mycobacterium smegmatis was also assessed as a surrogate for M. avium subsp. paratuberculosis. Two structures were constructed to hold three cattle carcasses each. Naturally infected tissues and ground beef inoculated with laboratory-cultured M. avium subsp. paratuberculosis and M. smegmatis were placed in nylon and plastic bags to determine effects of temperature and compost environment on viability over 250 days. After removal, samples were cultured and growth of both organisms was assessed after 12 weeks. After 250 days, M. avium subsp. paratuberculosis was still detectable by PCR, while M. smegmatis was not detected after 67 days of composting. Furthermore, M. avium subsp. paratuberculosis remained viable in both implanted nylon and plastic bags over the composting period. As the compost never reached a homogenous thermophilic (55 to 65°C) state throughout each structure, an in vitro experiment was conducted to examine viability of M. avium subsp. paratuberculosis after exposure to 80°C for 90 days. Naturally infected lymph tissues were mixed with and without compost. After 90 days, M. avium subsp. paratuberculosis remained viable despite exposure to temperatures typically higher than that achieved in compost. In conclusion, it is unlikely composting can be used as a means of inactivating M. avium subsp. paratuberculosis associated with cattle mortalities.

Transthoracic adrenal biopsy procedure using artificial carbon dioxide pneumothorax as outpatient procedure.

Many routes have been described for percutaneous adrenal gland biopsy. They require either a complex non-axial path or a long hydrodissection or even pass through an organ thereby increasing complications. We describe here an approach using an artificially-induced carbon dioxide (CO2) pneumothorax, performed as an outpatient procedure in a 57-year-old woman. Under local anaesthesia, 200 ml of CO2 was injected in the pleural space through a Veress needle under computed tomography fluoroscopy, to clear the lung parenchyma from the biopsy route. Using this technique, transthoracic adrenal biopsy can be performed under simple local anaesthesia as an safely outpatient procedure.

Lipiodol trans-arterial chemoembolization of hepatocellular carcinoma with idarubicin: first experience.

BACKGROUND: There is still no consensus about the best chemotherapeutic agent for transarterial chemoembolization (TACE). A recent in vitro study demonstrated that idarubicin, an anthracycline, was by far the most cytotoxic drug on human hepatocellular carcinoma (HCC) cell lines. Idarubicin is much more lipophilic than doxorubicin, leading to higher cell penetration through lipidic membranes and greater accumulation of the drug in the lipiodol. Furthermore, idarubicin has the ability to overcome multidrug resistance. Therefore, we designed this pilot human study to evaluate the safety and efficacy of lipiodol TACE using idarubicin. METHODS: In 21 consecutive patients treated by lipiodol TACE with idarubicin (10 mg) for HCC, safety data, tumor response (Response Evaluation Criteria in Solid Tumors, mRECIST), time to treatment failure (TTTF), and overall survival were evaluated. RESULTS: Postembolization syndrome was observed after 30.9% (17 of 55) of sessions. No patient died from a TACE-related complication. No hematological grade 3-5 adverse event was observed. At least one grade 3 or higher adverse event occurred in 19% (4 of 21) of patients. On imaging, no progression was encountered; four patients (24%) exhibited stable disease, 12 (57%) exhibited a partial response, and five (19%) exhibited a complete response. Median TTTF was 16.7 months (Kaplan-Meier analysis). At 6 months, 94.7% (95% confidence interval [CI] 68.1-99.2) of patients did not reach treatment failure, whereas treatment failure was not reached in 50.6% (95% CI 21.6-73.9) of patients at 1 year. Overall survival was 83.5% (95% CI 57-94.4) at 1 year. CONCLUSION: Idarubicin seems safe and effective in lipiodol TACE of HCC. This warrants further study to determine the potential of this drug to replace doxorubicin for TACE.

Intravoxel incoherent motion diffusion-weighted imaging in nonalcoholic fatty liver disease: a 3.0-T MR study.

PURPOSE: To compare pure molecular diffusion, D, perfusion-related diffusion, D*, and perfusion fraction, f, determined from diffusion-weighted (DW) magnetic resonance (MR) imaging on the basis of the intravoxel incoherent motion (IVIM) theory in patients with type 2 diabetes with and without liver steatosis. MATERIALS AND METHODS: This prospective study was approved by the appropriate ethics committee, and written informed consent was obtained from all patients. Between December 2009 and September 2011, 108 patients with type 2 diabetes (51 men, 57 women; mean age, 50 years) underwent 3.0-T single-voxel point-resolved proton MR spectroscopy of the liver (segment VII) to calculate the liver fat fraction from water (4.76 ppm) and methylene (1.33 ppm) peaks, corrected for T1 and T2 decay. Steatosis was defined as a liver fat fraction of at least 5.56%. DW imaging was performed by using a single-shot echo-planar sequence with 11 b values (0, 5, 15, 25, 35, 50, 100, 200, 400, 600, 800 sec/mm2). Liver D, D*, and f were measured and compared in patients with and patients without steatosis (Mann-Whitney test). RESULTS: The mean liver fat fraction was 7.8% (standard deviation, 9%; range, 0.99%-45%). Forty patients had liver steatosis. D was significantly lower in steatotic compared with nonsteatotic livers (mean, 1.03×10(-3) mm2/sec±0.23 [standard deviation] vs 1.24×10(-3) mm2/sec±0.15, respectively; P<.0001), as was D* (mean, 72.2×10(-3) mm2/sec±61.4 vs 110.6×10(-3) mm2/sec±79; P=.0025). However, f was significantly higher in steatotic compared with nonsteatotic livers (mean, 33.8%±9.4 vs 26.9%±8.8; P=.0003). CONCLUSION: D is significantly decreased in steatosis. The reduction in D* reflects decreased liver parenchymal perfusion in steatosis. Therefore, steatosis can affect diffusion parameters obtained with IVIM.

Macroscopic heterogeneity of liver fat: an MR-based study in type-2 diabetic patients.

OBJECTIVE: To assess the heterogeneity of liver fat deposition with MR of the liver in type-2 diabetic (T2D) patients. METHODS: We enrolled 121 consecutive T2D patients. The reference standard was 3.0-T (1)H-MR spectroscopy. Hepatic steatosis was defined as liver fat content (LFC) ≥5.56 %. A triple-echo gradient-echo sequence corrected for T1 recovery and T2* decay was used to calculate LFC in left and right livers and hepatic segments. Analyses were performed using a linear mixed model. RESULTS: Fifty-nine (48.8 %) patients had liver steatosis, whereas 62 (51.2 %) did not. Steatosis was greater in the right than in the left liver (P < 0.0001) [mean difference: 1.32 % (range: 0.01-8.75 %)]. In seven patients (5.8 %), LFC was <5.56 % in one side of the liver, whereas it was ≥5.56 % in the other. Steatosis of the left and right liver was heterogeneous at the segmental level in both non-steatotic (P < 0.001 and P < 0.0001 respectively) and steatotic (P < 0.0001 and P = 0.0002 respectively) patients [mean maximum difference: 3.98 % (range: 0.74-19.32 %)]. In 23 patients (19 %), LFC was <5.56 % in one segment, whereas it was ≥5.56 % in at least one other. CONCLUSION: Overall, the mean segmental/lobar variability of steatosis is low. However, segmental variability can sometimes lead to a misdiagnosis. KEY POINTS: There is a need for methods quantifying steatosis over a large region. Steatosis is usually greater in the right than left lobe of the liver. Steatosis within both left and right hepatic lobes is segmentally heterogeneous. Segmental variability of steatosis can result in misdiagnosis.

Prediction for steatosis in type-2 diabetes: clinico-biological markers versus 1H-MR spectroscopy.

OBJECTIVES: The SteatoTest, fatty liver index (FLI) and hepatic steatosis index (HSI) are clinico-biological scores of steatosis validated in general or selected populations. Serum adiponectin (s-adiponectin) and retinol binding protein 4 (s-RBP4) are adipokines that could predict liver steatosis. We investigated whether the Steatotest, FLI, HSI, s-adiponectin and s-RBP4 could be valid predictors of liver steatosis in type-2 diabetic (T2D) patients. METHODS: We enrolled 220 consecutive T2D patients. Reference standard was 3.0 T (1)H-MR spectroscopy (corrected for T1 and T2 decays). Intraclass correlation coefficients (ICCs), Kappa statistic measures of agreement, receiver operating characteristic (ROC) curves were assessed. RESULTS: Median liver fat content was 91 mg triglyceride/g liver tissue (range: 0-392). ICCs among the Steatotest, FLI, HSI, s-adiponectin, s-RBP4 and spectroscopy were low: 0.384, 0.281, 0.087, -0.297 and 0.048. Agreement between scores and spectroscopy was poor (Kappa range: 0.042-0.281). The areas under the ROC curves were low: 0.674, 0.647, 0.637, 0.616 and 0.540. S-adiponectin and s-RBP4 levels were strongly related to the presence of diabetic nephropathy (P = 0.0037 and P = 0.004; Mann-Whitney). CONCLUSION: The SteatoTest, FLI, HSI, s-adiponectin, s-RBP4 are not valid predictors of steatosis in T2D patients. Clino-biological markers cannot replace (1)H-MR spectroscopy for the assessment of liver fat in this population. KEY POINTS: (1) H-MR spectrosopy can reliably estimate the weight fraction of liver steatosis. Type-2 diabetes provides an interesting model for assessing liver steatosis. Clinico-biological markers seem to be invalid predictors for steatosis in type-2 diabetes.