Hepatic fat quantification in dual-layer computed tomography using a three-material decomposition algorithm.

OBJECTIVES: The purpose of this study was to evaluate a three-material decomposition algorithm for hepatic fat quantification using a dual-layer computed tomography (DL-CT) and MRI as reference standard on a large patient cohort. METHOD: A total of 104 patients were retrospectively included in our study, i.e., each patient had an MRI exam and a DL-CT exam in our institution within a maximum of 31 days. Four regions of interest (ROIs) were positioned blindly and similarly in the liver, by two independent readers on DL-CT and MRI images. For DL-CT exams, all imaging phases were included. Fat fraction agreement between CT and MRI was performed using intraclass correlation coefficients (ICC), determination coefficients R2, and Bland-Altman plots. Diagnostic performance was determined using sensitivity, specificity, and positive and negative predictive values. The cutoff for steatosis was 5%. RESULTS: Correlation between MRI and CT data was excellent for all perfusion phases with ICC calculated at 0.99 for each phase. Determination coefficients R2 were also good for all perfusion phases (about 0.95 for all phases). Performance of DL-CT in the diagnosis of hepatic steatosis was good with sensitivity between 89 and 91% and specificity ranging from 75 to 80%, depending on the perfusion phase. The positive predictive value was ranging from 78 to 93% and the negative predictive value from 82 to 86%. CONCLUSION: Multi-material decomposition in DL-CT allows quantification of hepatic fat fraction with a good correlation to MRI data. CLINICAL RELEVANCE STATEMENT: The use of DL-CT allows for detection of hepatic steatosis. This is especially interesting as an opportunistic finding CT performed for other reasons, as early detection can help prevent or slowdown the development of liver metabolic disease. KEY POINTS: • Hepatic fat fractions provided by the dual-layer CT algorithm is strongly correlated with that measured on MRI. • Dual-layer CT is accurate to detect hepatic steatosis ≥ 5%. • Dual-layer CT allows opportunistic detection of steatosis, on CT scan performed for various indications.

Radiological Response Is Associated with Better Outcomes and Should Be Considered a Therapeutic Target in Crohn's Disease.

BACKGROUND: The aim of the study was to identify factors associated with a radiological response and to assess the impact of radiological improvement in long-term outcomes in small bowel (SB) Crohn's disease (CD) patients. METHODS: We performed a retrospective study from June 2011 to June 2017 in the tertiary center, Claude Huriez Hospital in Lille, France. All SB CD patients, who underwent two magnetic resonance enterographies (MRE) 3-12 months apart, with at least 1-year follow-up after the second MRE, were included. Signs of radiological inflammation were identified by two expert radiologists in CD. Patients were classified as radiological responders (RR) and non-responders (NR). Hospitalization rates, adjustment of treatment, and surgical or endoscopic interventions were assessed and compared between RR and NR. Factors associated with a radiological response were also studied using the Cox model. RESULTS: One hundred and fifteen SB CD patients were included with a median follow-up of 17 months (IQR 11.6-28.3). There were 54 (47%) RR and 61 (53%) NR. The risk of surgical or endoscopic intervention was higher in NR than RR (p = 0.04), and the median delay until a surgical or endoscopic intervention was shorter in NR (p = 0.04). Multifocal disease, a hypersignal on diffusion-weighted or dynamic contrast-enhanced imaging, a stricture, or a fistula was significantly associated with a decreased probability of a radiological response (p < 0.05). CONCLUSION: This study shows that a radiological response is associated with a decreased risk of surgical or endoscopic intervention and should be considered as a therapeutic target in CD patients.

Laparoscopic Partial ALPPS: Much Better Than ALPPS!

Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS) has emerged as an alternative for patients with bilobar colorectal liver metastasis deemed unresectable due to inadequate future remnant liver (FRL). Nevertheless, high morbidity and mortality rates have been reported. In this setting, including hepatobiliary scintigraphy in the clinical and surgical management of patients offered ALPPS has been advocated to both assess eligibility for ALPPS stagel and suitable time for ALPPS stage2. Recently, it was stated that partial ALPPS with a liver split restricted to 50% of the transection line (or up to the middle hepatic vein in case of right extended hepatectomy) and a shortened stagel allows improving the postoperative course without precluding the inter-stages FRL hypertrophy. We describe a case series of p-ALPPS with stagel performed laparoscopically, including sequential assessments of the FRL volumes and functions via pre-stagel and pre-stage2 computed tomography volumetry and HIDA SPECT-scintigraphy. In five patients, laparoscopic p-ALPPS was associated with rapid and significant gain of remnant functional volume - much better than previously observed for ALPPS - facilitating early stage2 without inflammatory adherences. In conclusion, laparoscopic p-ALPPS is feasible and seems less aggressive than the original ALPPS technique with total transection. It may be an interesting alternative to the classical portal vein embolization (PVE) and two-stage hepatectomy strategy.

Acute Jejunoileal Diverticulitis: Multicenter Descriptive Study of 33 Patients.

OBJECTIVE: Acute jejunoileal diverticulitis is a very rare and potentially serious disease affecting mostly elderly patients. The diagnosis is based on imaging but remains underrecognized. The purpose of this study is to describe the clinical and CT features and the outcomes of patients with acute jejunoileal diverticulitis. MATERIALS AND METHODS: Cases of acute jejunoileal diverticulitis managed at three French hospitals November 2005 through January 2015 were identified retrospectively. The final diagnosis relied either on a clinical and radiologic data review by a panel of experts or on surgical findings. Demographic, clinical, laboratory, and 18-month outcome data were collected. CT scans were reviewed by two radiologists who reached a consensus about the presence of an inflammatory diverticulum, evidence of complications, and presence of other bowel diverticula. RESULTS: We identified 33 cases of acute jejunoileal diverticulitis in 33 patients with a median age of 78 years, including 30 (91%) patients in whom an inflammatory diverticulum was identified at the jejunum (n = 26, 87%) or ileum (n = 4, 13%). Extraintestinal gas was seen in 10 (30%) patients and extraintestinal fluid in 11 (33%) patients. Other small-bowel diverticula were visible in all 33 patients. The diverticulitis was mild and resolved with nonoperative treatment in 22 (67%) patients and was severe in the remaining 11 (33%) patients, eight of whom required emergent surgery. CONCLUSION: Acute jejunoileal diverticulitis is a rare and usually nonserious condition that chiefly involves the jejunum. A detailed CT assessment may allow nonoperative treatment.

Impact of arterial input function selection on the accuracy of dynamic contrast-enhanced MRI quantitative analysis for the diagnosis of clinically significant prostate cancer.

PURPOSE: Using a limited temporal resolution dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) dataset to assess the impact of the arterial input function (AIF) choice on the transfer constant (K(trans) ) to distinguish prostate carcinoma (PCa) from benign tissue. MATERIALS AND METHODS: Thirty-eight patients with clinically important peripheral PCa (≥0.5 cc) were retrospectively studied. These patients underwent 1.5T multiparametric prostate MR with PCa and benign regions of interest (ROIs) selected using a visual registration with morphometric reconstruction obtained from radical prostatectomy. Using three pharmacokinetic (PK) analysis software programs, the mean K(trans) of ROIs was computed using three AIFs: an individual AIF (Ind-AIF) and two literature population average AIFs of Weinmann (W-AIF) and of Fritz-Hansen (FH-AIF). A pairwise comparison of the area under the receiver operating characteristic curves (AUROCC) obtained with different AIFs was performed. RESULTS: AUROCCs obtained with W-AIF (ranging from 0.801 to 0.843) were significantly higher than FH-AIF (ranging from 0.698 to 0.780, 0.002 ≤ P ≤ 0.045) and similar to or higher than Ind-AIF (ranging from 0.591 to 0.839, 0.014 ≤ P ≤ 0.9). Ind-AIF and FH-AIF provided similar AUROCC (0.34 ≤ P ≤ 0.81). The pairwise correlation of K(trans) values was moderate to very strong when comparing W-AIF with FH-AIF (the Spearman's correlation coefficients [SCCs] ranged from 0.55 to 0.93) and very weak to moderate when comparing W-AIF with Ind-AIF (the SCCs ranged from 0.018 to 0.59) or FH-AIF with Ind-AIF (the SCCs ranged from 0.30 to 0.51). CONCLUSION: W-AIF yielded a higher performance than FH-AIF and a similar or higher performance than Ind-AIF in distinguishing PCa from benign tissue.

Sarcopenia does not affect liver regeneration and postoperative course after a major hepatectomy. A prospective study on 125 patients using CT volumetry and HIDA scintigraphy.

BACKGROUND & OBJECTIVES: Sarcopenia is a morbi-mortality risk factor in digestive surgery, though its impact after major hepatectomy (MH) remains unknown. This prospective pilot study investigated whether volume and function of a regenerating liver is influenced by body composition. METHODS: From 2011 to 2016, 125 consecutive patients had computed tomography and 99mTc-labelled-mebrofenin SPECT-scintigraphy before and after MH at day 7 and 1 month for measurements of liver volumes and functions. L3 vertebra muscle mass identified sarcopenia. Primary endpoint was the impact of sarcopenia on regeneration capacities (i.e. volume/function changes and post-hepatectomy liver failure (PHLF) rate). Secondary endpoint was 3-month morbi-mortality. RESULTS: Sarcopenic patients (SP; N = 69) were significantly older than non-sarcopenic (NSP), with lower BMI and more malignancies, but with comparable liver function/volume at baseline. Postoperatively, SP showed higher rates of ISGLS_PHLF (24.6 % vs 10.9 %; p = 0.05) but with comparable rates of severe morbidity (23.2 % vs 16.4 %; p = 0.35), overall (8.7 % vs 3.6 %; p = 0.3) and PHLF-related mortality (8,7 % vs 1.8 %; p = 0.075). After matching on the extent of resection or using propensity score, regeneration and PHLF rates were similar. CONCLUSION: This prospective study using first sequential SPECT-scintigraphy showed that sarcopenia by itself does not affect liver regeneration capacities and short-term postoperative course after MH.

Detection and characterization of pancreatic lesion with artificial intelligence: The SFR 2023 artificial intelligence data challenge.

PURPOSE: The purpose of the 2023 SFR data challenge was to invite researchers to develop artificial intelligence (AI) models to identify the presence of a pancreatic mass and distinguish between benign and malignant pancreatic masses on abdominal computed tomography (CT) examinations. MATERIALS AND METHODS: Anonymized abdominal CT examinations acquired during the portal venous phase were collected from 18 French centers. Abdominal CT examinations were divided into three groups including CT examinations with no lesion, CT examinations with benign pancreatic mass, or CT examinations with malignant pancreatic mass. Each team included at least one radiologist, one data scientist, and one engineer. Pancreatic lesions were annotated by expert radiologists. CT examinations were distributed in balanced batches via a Health Data Hosting certified platform. Data were distributed into four batches, two for training, one for internal evaluation, and one for the external evaluation. Training used 83 % of the data from 14 centers and external evaluation used data from the other four centers. The metric (i.e., final score) used to rank the participants was a weighted average of mean sensitivity, mean precision and mean area under the curve. RESULTS: A total of 1037 abdominal CT examinations were divided into two training sets (including 500 and 232 CT examinations), an internal evaluation set (including 139 CT examinations), and an external evaluation set (including 166 CT examinations). The training sets were distributed on September 7 and October 13, 2023, and evaluation sets on October 15, 2023. Ten teams with a total of 93 members participated to the data challenge, with the best final score being 0.72. CONCLUSION: This SFR 2023 data challenge based on multicenter CT data suggests that the use of AI for pancreatic lesions detection is possible on real data, but the distinction between benign and malignant pancreatic lesions remains challenging.

Volumetric gain of the liver after major hepatectomy in obese patients: a case-matched study in 84 patients.

OBJECTIVE: The objective was to determine the liver volumetric recovering capacity and postoperative course after major hepatectomy in obese patients through a case-matched study. BACKGROUND: In literature, the impact of obesity on liver recovering has been analyzed only indirectly in terms of morbimortality but never through volumetric assessment. PATIENTS AND METHOD: Between 2005 and 2011, 42 patients with body mass index (BMI) 30 or higher (Ob group) underwent major hepatectomy and were matched with 42 patients with BMI 25 or lower (NonOb group) on the magnitude of resection (number of resected segments ±1, remnant liver volume to total liver volume, RLV/TLV, ±5%). The RLV was measured on computed tomographic slices preoperatively and postoperatively at 1 month (RLV-1M) for all patients and within 3 to 12 months in 42 paired patients (median = 6 months, RLV-6M). Considering hepatomegaly in Ob group, RLV was also normalized to body weight (RLVBWR). The liver volumetric gain was expressed as a relative increase [(RLV-1M - RLV)/RLV] or increase in RLVBWR. RESULTS: The Ob and NonOb groups were comparable regarding clinicopathological data, except for arterial hypertension (48% vs 19%; P = 0.005), mean steatosis (24% vs 10%; P = 0.03), and fibrosis incidence (33% vs 10%; P = 0.008). Ob group showed longer operative time and higher blood losses. There were no intergroup differences in liver failure (both 7.1%) and 90-day morbimortality. Despite comparable RLV/TLV (38.1% vs 37.7%; P = 0.13), the relative liver volumetric gain at 1 month was significantly lower in Ob group (+93% vs +115%; P = 0.002), as well as RLVBWR increase (+0.59% vs +0.79%; P < 0.001). The RLV-1M represented 66.2% of initial TLV in Ob group compared with 73.8% (P = 0.005) in NonOb group. This delay in relative volumetric gain persisted at 6 months (+105.4% vs +137.6%; P = 0.009), the RLV-6M representing 71.2% vs 82.4% of initial TLV (P = 0.014). CONCLUSIONS: In a methodologically robust trial in the first cohort reported up to date, the regenerative response in obese patients was comparatively slower based on their initial TLV or body weight.

[New methods for exploration of the small intestine]. / Nouvelles méthodes d'exploration de l'intestin grêle.

For ten years, a lot of advances have been achieved for the morphological exploration of the small intestine as well as with CT and MR enterography than with wireless capsule endoscopy. These investigations have renewed the approaches of different diseases that can affect the small intestine: tumors, especially sub-mucosal tumors (CT enterography), iron-deficiency anemia (capsule endoscopy) and follow-up of patients with Crohn's disease of the small intestine (MR enterography). Balloon enteroscopy may then allow therapeutic approach when needed (treatment of bleeding angiodysplasia).

Pneumatosis intestinalis and portal venous gas in mechanical small bowel obstruction: Is it worrisome?

PURPOSE: The purpose of this study was to evaluate the clinical significance of pneumatosis intestinalis (PI) and portal venous gas (PVG) in patients with mechanical small bowel obstruction (SBO), using surgical findings or clinical follow-up as standard of reference. MATERIALS AND METHODS: Fourteen patients with mechanical SBO associated with PI and PVG were retrospectively included. There were 7 men and 7 women with a mean age of 59±19 (SD) (range: 25-93 years). CT examinations were reviewed by two radiologists to confirm the diagnosis of mechanical SBO and make a description of PI. Interobserver agreement was calculated. The reference standard was intraoperative appearance of the bowel wall (10/14; 71%) or the recovery of a normal bowel function in patients who were managed conservatively (4/14; 29%). RESULTS: Among the 10 patients who underwent surgery, a normal appearance of the bowel in association with PI on CT was found intraoperatively in 8/10 (80%) patients and a reversible ischemia in the remaining 2/10 (20%) patients. The four patients who were managed conservatively recovered normal bowel function. Two patients died within two weeks following SBO. CONCLUSION: PI and PVG are not specific signs of bowel necrosis in mechanical SBO.

Consequences of TIPSS placement on the body composition of patients with cirrhosis and severe portal hypertension: a large retrospective CT-based surveillance.

BACKGROUND: Body composition may be modified after improvement of portal hypertension (PHT) by transjugular intrahepatic portosystemic shunt (TIPSS) insertion. AIMS: To evaluate changes in body composition following TIPSS placement, their relationship with radiological TIPSS patency and function, and the predictive value of these parameters METHODS: We retrospectively included 179 patients with cirrhosis who underwent TIPSS placement in our centre for severe PHT from 2011 to 2017. CT scan-based surveillance was performed at baseline, 1-3 (M1-M3) and 6 months (M6). RESULTS: The median model for end-stage liver disease (MELD) score was 11.4 (8.8-15.1) and Child-Pugh score 8 (7-9). Only the MELD score (HR 1.14, 95% CI 1.08-1.20) and sarcopenia assessed by transversal right psoas muscle thickness at the umbilical level/height (TPMPT/height) (HR 0.86, 95% CI 0.79-0.96) were independently associated with 6-month mortality on multivariate analysis. After TIPSS insertion, TPMT/height increased from 19 mm/m (baseline) to 19.6 mm/m (M1-M3, P = 0.004) and 21.1 mm/m (M6, P < 0.0001). The improvement and its extent were dependent on the radiological patency and dysfunction of TIPSS. Subcutaneous fat surface (SCFS) increased from 183.4 to 193 cm2 (P < 0.0001) and 229.8 cm2 (P < 0.0001), respectively. We observed a decrease in visceral fat surface (VFS) between baseline and M1-M3 (163.5-140.5 cm2 [P < 0.0001]), but not between M1-M3 and M6 (140.5-141.2 cm2 [P = 0.9]). SCFS and VFS did not seem to be modified by radiological TIPSS patency and dysfunction. CONCLUSIONS: Sarcopenia is independently associated with 6-month outcome and improves after TIPSS placement, together with an inverse evolution of subcutaneous and visceral fat. TIPSS not only treats PHT but also improves body composition.

Bowel damage and disability in Crohn's disease: a prospective study in a tertiary referral centre of the Lémann Index and Inflammatory Bowel Disease Disability Index.

BACKGROUND: The notion of Crohn's disease (CD) as a chronic, progressive and disabling condition has led to the development of new indexes: the Lémann Index measuring cumulative bowel damage and the Inflammatory Bowel Disease (IBD) Disability Index, assessing functional disability. AIMS: To measure the Lémann Index and the IBD Disability Index in a large prospective cohort of CD patients and to assess the correlation between these two indexes. METHODS: We performed a prospective study in a tertiary referral centre including all consecutive CD outpatients. We assessed the Lémann Index and the IBD Disability Index questionnaire in all patients. RESULTS: One hundred and thirty CD patients were consecutively included. The mean Lémann Index (±SD) was 11.9 ± 14.1 and ranged from 0 to 72.5 points. Factors associated with a high bowel damage score were: disease duration, anal location, previous intestinal resection, clinical and biological disease activity, exposure to immunosuppressants, and exposure to anti-TNF (P < 0.005). Among patients exposed to anti-TNF, the Lémann Index was lower in those who were exposed in the first 2 years of their disease (P = 0.015). The mean IBD Disability Index was 28.8 ± 6.3 and ranged from 0 to 71 points. The factors associated with high disability score were: female gender, anal location, extra digestive manifestations, clinical and biological disease activity and exposure to anti-TNF (P < 0.005). No correlation was observed between the Lémann Index and IBD Disability Index (P = 0.15). CONCLUSIONS: This is the first study to prospectively evaluate the Lémann Index and the IBD Disability Index in a large cohort of CD patients in a tertiary centre. Early introduction of anti-TNF treatment was associated with lower bowel damage scores, and no correlation was observed between the Lémann Index and the IBD Disability Index. Further dedicated prospective studies are necessary to confirm these results.

Non-invasive assessment of liver fibrosis by transient elastography in post transfusional iron overload.

BACKGROUND: Liver fibrosis, assessed by biopsy, is the main complication of post transfusional liver iron overload. Transient elastography (TE) is a new, non invasive method able to measure liver stiffness (LS) caused by fibrosis. METHOD: We prospectively evaluated the predictive value of LS measurement for liver fibrosis evaluation in 15 chronically transfused patients and compared these results with the METAVIR histological fibrosis stage from liver biopsies. RESULTS: Mean TE values significantly differed in patients with severe fibrosis (METAVIR F3, F4): 9.1 (+/-3.7 SD) kPa from those with mild or no fibrosis (METAVIR F0, F1, F2): 5.9 (+/-1.8 SD) kPa (P = 0.046). TE value above 6.25 kPa (Se = 80%; Sp = 70%; AUROC = 0.820) identified patients at risk for severe fibrosis (Negative Predictive Value 88%; Positive Predictive Value 57%). CONCLUSION: Transient elastography appears to be a reliable tool to evaluate liver fibrosis in post-transfusional iron overload.

Impact of sarcopenia on outcomes of patients undergoing pancreatectomy: A retrospective analysis of 107 patients.

To evaluate the prevalence of sarcopenia in patients undergoing pancreatic surgery and to examine its impact on the surgical outcomes and survival of patients.Skeletal muscle index (SMI) was measured on preoperative CT. A patient was considered sarcopenic if SMI was <38.5 cm/m for a female or <52.4 cm/m for a male. Postoperative pancreatic fistula (POPF) and severe morbidity (Clavien≥3) were analyzed. Survival of patients with cancer was calculated using the Kaplan-Meier method.In total, 107 consecutive patients were included. Among them, 50 (47%) patients were sarcopenic and 65 (60%) were undernourished. The rates of severe morbidity and mortality were comparable between sarcopenic and nonsarcopenic groups. However, all POPF grade B or C and deaths occurred in the sarcopenic or nonsarcopenic overweight group (BMI > 25) with significantly lengthened hospital stays (P = .003). After pancreatectomy for cancer, 31 (40.2%) patients showed postoperative recurrence and 23 (29.9%) died after a median follow-up of 15 ±â€Š13.5 months. Despite comparable histological types and stages, the median overall and disease-free survivals were lower in sarcopenic patients (16 months vs not reached, P = .02 and 11.1 months vs 22.5 months; P = .04, respectively). The multivariate analysis revealed that, sarcopenia trended to increase the risk of death (HR = 2.04, P = .07).Sarcopenia negatively impacted short- and long-term outcomes in patients undergoing pancreatectomy.

Quantification by magnetic resonance imaging and liver consequences of post-transfusional iron overload alone in long term survivors after allogeneic hematopoietic stem cell transplantation (HSCT).

We quantified and studied the impact of post transfusional iron overload alone in post allogeneic HSCT. Median number of RBCs was 18. Ferritin was 532 mg/L. Liver iron content (LIC) was 117 mmoles/gdw. Correlation RBCs and ferritin was (r=0.81); RBCs and LIC was (r=0.84). The high ferritin group differed from normal ferritin group in terms of RBCs transfused (p<10(-3)), ALT (p<0.009). But occurrence of liver dysfunction was not significant. Magnitude of iron overload correlates closely to the number of RBCs and is quantified by MRI. Impact on liver dysfunction is moderate in absence of co-morbidity.