Choledocholithiasis: repetitive thick-slab single-shot projection magnetic resonance cholangiopancreaticography versus endoscopic ultrasonography

This prospective study compares repetitive thick-slab single-shot projection magnetic resonance cholangiopancreatography (MRCP) with endoscopic ultrasonography (EUS) for the detection of choledocholithiasis. Fifty-seven consecutive patients (36 women, mean age 61) referred for suspected choledocholithiasis underwent MRCP, followed by EUS. Each procedure was performed by different operators blinded to the results of the other investigation. MR technique included a turbo spin-echo T2-weighted axial sequence with selective fat saturation (SPIR/TSE, TE=70ms, TR=1,600ms), followed by coronal dynamic MRCP. The same thick-slab slice was sequentially acquired 12 times as breath-hold single-shot projection imaging (SSh, TE=900ms, TE=8,000ms) centred on the common bile duct (CBD). Two experienced radiologists independently and blindly evaluated MR images for the detection of CBD stones. Their inter-observer agreement kappa was determined. Secondly, the two observers read MR images in consensus again. CBD stones were demonstrated in 18 out of 57 patients (31.6 %) and confirmed by endoscopic retrograde cholangiography (ERCP, n=17) or intraoperative cholangiography (n=1). Clinical follow-up served as the "gold standard” in patients with negative results without following invasive procedure (n=28). Sensitivity, specificity, accuracy, positive and negative predictive value for MRCP resulting from consensus reading were 94.9%, 94.4%, 94.7%, 97.4% and 89.5%, respectively. Corresponding values of EUS were 97.4%, 94.4%, 96.5%, 97.4% and 94.4%. Inter-observer agreement kappa was 0.81. Repetitive thick-slab single-shot projection MRCP is an accurate non-invasive imaging modality for suspected choledocholithiasis and should be increasingly used to select those patients who require a subsequent therapeutic procedure, namely ERC

Evaluation of the performances of a single-use duodenoscope: Prospective multi-center national study

Objectives: A single-use duodenoscope (SUD) has been recently developed to overcome issues with endoscopic retrograde cholangiopancreatography (ERCP)-related cross-infections. The aim was to evaluate SUD safety and performance in a prospective multi-centre study. Methods: All consecutive patients undergoing ERCP in six French centers were prospectively enrolled. All procedures were performed with the SUD; in case of ERCP failure, operators switched to a reusable duodenoscope. Study outcomes were the successful completion of the procedure with SUD, safety and operators’ satisfaction based on a VAS 0–10 and on 22 qualitative items. The study protocol was approved by French authorities and registered (ID-RCB: 2020-A00346-33). External companies collected the database and performed statistical analysis. Results: Sixty patients (34 females, median age 65.5 years old) were enrolled. Main indications were bile duct stones (41.7%) and malignant biliary obstruction (26.7%). Most ERCP were considered ASGE grade 2 (58.3%) or 3 (35.0%). Fifty-seven (95.0%) procedures were completed using the SUD. Failures were unrelated to SUD (one duodenal stricture, one ampullary infiltration, and one tight biliary stricture) and could not be completed with reusable duodenoscopes. Median operators’ satisfaction was 9 (7–9). Qualitative assessments were considered clinically satisfactory in a median of 100% of items and comparable to a reusable duodenoscope in 97.9% of items. Three patients (5%) reported an adverse event. None was SUD-related. Conclusions: The use of a SUD allows ERCP to be performed with an optimal successful rate. Our data show that SUD could be used for several ERCP indications and levels of complexity

Polynomial approximation of quasipolynomials based on digital filter design principles

This contribution is aimed at a possible procedure approximating quasipolynomials by polynomials. Quasipolynomials appear in linear time-delay systems description as a natural consequence of the use of the Laplace transform. Due to their infinite root spectra, control system analysis and synthesis based on such quasipolynomial models are usually mathematically heavy. In the light of this fact, there is a natural research endeavor to design a sufficiently accurate yet simple engineeringly acceptable method that approximates them by polynomials preserving basic spectral information. In this paper, such a procedure is presented based on some ideas of discrete-time (digital) filters designing without excessive math. Namely, the particular quasipolynomial is subjected to iterative discretization by means of the bilinear transformation first; consequently, linear and quadratic interpolations are applied to obtain integer powers of the approximating polynomial. Since dominant roots play a decisive role in the spectrum, interpolations are made in their very neighborhood. A simulation example proofs the algorithm efficiency. © Springer International Publishing Switzerland 2016

Assessment of intrahepatic blood flow by Doppler ultrasonography: Relationship between the hepatic vein, portal vein, hepatic artery and portal pressure measured intraoperatively in patients with portal hypertension

<p>Abstract</p> <p>Background</p> <p>Abnormality of hepatic vein (HV) waveforms evaluated by Doppler ultrasonography has been widely studied in patients with chronic liver disease. We investigated the correlation between changes in HV waveforms and portal vein velocity (PVVel), the hepatic artery pulsatility index (HAPI), and also the extent of abnormal Doppler HV waveforms expressed as damping index (DI), severity of portal hypertension expressed as Child-Pugh scores and portal pressure (PP) measured directly from patients with portal hypertension (PHT) to evaluate the indicative value of abnormal HV waveforms and discuss the cause of abnormal HV waveform.</p> <p>Methods</p> <p>Sixty patients who had been diagnosed with PHT and accepted surgical therapy of portosystemic shunts were investigated. PP was measured intraoperatively. Thirty healthy volunteers with no history of chronic liver disease were enrolled as the control group. HV waveforms were categorized as triphasic, biphasic or monophasic. DI was compared as the quantitative indicator of abnormal HV waveforms. Another two Doppler parameters, PVVel and HAPI were also measured. These Doppler features were compared with PP, Child-Pugh scores and histological changes assessed by liver biopsy.</p> <p>Results</p> <p>In the patient group, the Doppler flow waveforms in the middle HV were triphasic in 31.6%, biphasic in 46.7%, and monophasic in 21.6% of subjects. These figures were 86.7%, 10.0%, and 3.3%, respectively, in healthy subjects. With the flattening of HV waveforms, the HAPI increased significantly (<it>r </it>= 00.438, <it>p </it>< 0.0001), whereas PVVel decreased significantly (<it>r </it>= -0.44, <it>p <</it>0.0001). Blood flow parameters, HAPI, PVVel and HV-waveform changes showed no significant correlations with Child-Pugh scores. The latter showed a significant correlation with PP (<it>r </it>= 0.589, <it>p </it>= 0.044). Changes of HV waveform and DI significantly correlated with PP (<it>r </it>= 0.579, <it>r </it>= 0.473, <it>p <</it>0.0001), and significant correlation between DI and Child-Pugh scores was observed (<it>r </it>= 0.411, <it>p = </it>0.001). PP was significantly different with respect to nodule size (<it>p </it>< 0.05), but HV-waveform changes were not significantly correlated with pathological changes.</p> <p>Conclusion</p> <p>In patients with PHT, a monophasic HV waveform indicates higher portal pressure. Furthermore, quantitative indicator DI can reflect both higher portal pressure and more severe liver dysfunction. Flattening of HV waveforms accompanied by an increase in the HAPI and decrease in PVVel support the hypothesis that histological changes reducing HV compliance be the cause of abnormality of Doppler HV waveforms from the hemodynamic angle.</p

Lung transplantation for pulmonary fibrosis in dyskeratosis congenita: Case Report and systematic literature review

<p>Abstract</p> <p>Background</p> <p>Dyskeratosis congenita (DC) is a progressive, multi-system, inherited disorder of telomere biology with high risks of morbidity and mortality from bone marrow failure, hematologic malignancy, solid tumors and pulmonary fibrosis. Hematopoietic stem cell transplantation (HSCT) can cure the bone marrow failure, but it does not eliminate the risks of other complications, for which life-long surveillance is required. Pulmonary fibrosis is a progressive and lethal complication of DC.</p> <p>Case presentation</p> <p>In this report, we describe a patient with DC who developed pulmonary fibrosis seven years after HSCT for severe aplastic anemia, and was successfully treated with bilateral lung transplantation. We also performed a systematic literature review to understand the burden of pulmonary disease in patients with DC who did or did not receive an HSCT. Including our patient, we identified 49 DC patients with pulmonary disease (12 after HSCT and 37 without HSCT), and 509 with no reported pulmonary complications.</p> <p>Conclusion</p> <p>Our current case and literature review indicate that pulmonary morbidity is one of the major contributors to poor quality of life and reduced long-term survival in DC. We suggest that lung transplantation be considered for patients with DC who develop pulmonary fibrosis with no concurrent evidence of multi-organ failure.</p

Results of Conserve Plus Hip Resurfacing: prospective clinical, radiographic and ion study.

We report the 3- to 5-year clinical, radiographic and serum ion level results of a prospective consecutive cohort of 42 hip resurfacing arthroplasties using the Conserve Plus implant in 39 male patients that were operated on by a single surgeon in a community hospital. Average age was 53 years (range 34-67) at surgery.  There was one revision for a subcapital neck fracture. There were no surgery related complications. The survival of the implant was 95%.  Clinical evaluation showed excellent results with a modified Charnley score of 17.6/18, Harris Hip Score of 96.2/100, WOMAC  of 95.1/100, Oxford Score 15.3, and UCLA-Activity Score of 8/10. Radiographic analysis showed no implant at risk, no migration or signs of loosening, no neck narrowing and no osteolysis at final follow-up. Average cup inclination angle was 43.5° with 2 outliers (34° and 57°).  Ion level study showed average cobalt in serum 1.04 µg/l (range 0-4) for the whole group, 0.7 µg/l (range 0 -3) in patients with unilateral resurfacing and 2.0 µg/l (range 0 – 4) in patients with bilateral resurfacing.  All patients had ion levels within the safe zone