René Warschkow

Local excision and endoscopic posterior mesorectal resection versus low anterior resection in T1 rectal cancer.

Rectum‐preserving endoscopic posterior mesorectal resection (EPMR) removes the local lymph nodes in a minimally invasive manner and completes tumour staging after transanal local excision (TE). The aim of this study was to compare the morbidity and mortality of TE and EPMR with those of low anterior resection (LAR) in patients with T1 rectal cancer.

Is sphincter preservation reasonable in all patients with rectal cancer

PurposeModern sphincter-preserving surgery for ultralow rectal carcinoma has a comparable oncological radicality to abdomino-perineal extirpation (APE). The aim of this study was to assess the long-term morbidity of ultralow anterior resection (ULAR) and its impact on quality of life (QoL)MethodsThe medical records of 142 consecutive patients who underwent surgery for ultralow rectal carcinoma from January 1991 to December 2004 were reviewed retrospectively. The rate of rehospitalisation and rate of non-reversed temporary stomas (“failure” stoma) were analysed. Generic and cancer-specific quality of life questionnaires were used to assess quality of life.ResultsThere were a total of 82 ULAR and 60 APE. After ULAR, 25 (30.5%) of the patients were readmitted, stenosis and anastomotic leakage being the main reasons. After APE, only 2 (3.3%) of the patients were readmitted (Pu2009<u20090.001). The rate of patients with a permanent stoma after sphincter-saving surgery was 22.0%. The failure rate was higher for older patients (Pu2009=u20090.005) and for coloanal pull-through anastomosis (Pu2009=u20090.001). The exploratory analysis revealed a negative impact of a “failure” stoma on QoL.ConclusionSevere long-term morbidity and high failure rate of stoma reversal have a significantly worse impact on QoL after ULAR; therefore, APE is a valid alternative to ULAR, especially in elder patients with planned coloanal pull-through anastomosis.

Safety and morbidity after ultra-low coloanal anastomoses: J-pouch vs end-to-end reconstruction

Background and aimsAnastomotic failure after ultra-low anterior rectum resection is the most important complication, and it is influenced by the type of reconstruction. The aim of this study was to compare retrospectively the straight coloanal anastomosis with the J-pouch reconstruction concerning the development of anastomotic leakage.Materials and methodsFifty-six of 381 consecutive patients underwent low anterior rectum resection with total mesorectal excision and ultra-low coloanal anastomosis at 3–4xa0cm from the anocutan line. A 5-cm J-pouch (side-to-end) was performed in 25, a straight coloanal anastomosis in 25, and a coloplasty in 6 patients, respectively.Results/findingsNo influence by age, body mass index, and operating time on anastomotic leakage rate was found. Leakage was found in eight patients with straight coloanal anastomosis, resulting in a leakage rate of 32% compared to one patient in the J-pouch group (Pu2009=u20090.023).Interpretation/conclusionPatient’s safety is higher after J-pouch reconstruction because of the lower anastomotic failure rate, and functional results had been reported as similar after J-pouch reconstruction and straight coloanal anastomosis. Therefore, we clearly argue for a J-pouch reconstruction as the standard method after ultra-low coloanal anastomosis.

Ultralow dose CT for pulmonary nodule detection with chest x-ray equivalent dose – a prospective intra-individual comparative study

AbstractPurposeTo prospectively evaluate the accuracy of ultralow radiation dose CT of the chest with tin filtration at 100xa0kV for pulmonary nodule detection.Materials and methods202 consecutive patients undergoing clinically indicated chest CT (standard dose, 1.8u2009±u20090.7xa0mSv) were prospectively included and additionally scanned with an ultralow dose protocol (0.13u2009±u20090.01xa0mSv). Standard dose CT was read in consensus by two board-certified radiologists to determine the presence of lung nodules and served as standard of reference (SOR). Two radiologists assessed the presence of lung nodules and their locations on ultralow dose CT. Sensitivity and specificity of the ultralow dose protocol was compared against the SOR, including subgroup analyses of different nodule sizes and types. A mixed effects logistic regression was used to test for independent predictors for sensitivity of pulmonary nodule detection.Results425 nodules (mean diameter 3.7u2009±u20092.9xa0mm) were found on SOR. Overall sensitivity for nodule detection by ultralow dose CT was 91%. In multivariate analysis, nodule type, size and patients BMI were independent predictors for sensitivity (pu2009<u20090.001).ConclusionsUltralow dose chest CT at 100xa0kV with spectral shaping enables a high sensitivity for the detection of pulmonary nodules at exposure levels comparable to plain film chest X-ray.Keypoints• 91% of all lung nodules were detected with ultralow dose CTn • Sensitivity for subsolid nodule detection is lower in ultralow dose CT (77.5%)n • The mean effective radiation dose in 202 patients was 0.13xa0mSvn • Ultralow dose CT seems to be feasible for lung cancer screening

Computer-aided detection (CAD) of solid pulmonary nodules in chest x-ray equivalent ultralow dose chest CT - first in-vivo results at dose levels of 0.13 mSv

OBJECTIVESnTo determine the value of computer-aided detection (CAD) for solid pulmonary nodules in ultralow radiation dose single-energy computed tomography (CT) of the chest using third-generation dual-source CT at 100kV and fixed tube current at 70 mAs with tin filtration.nnnMETHODSn202 consecutive patients undergoing clinically indicated standard dose chest CT (1.8±0.7 mSv) were prospectively included and scanned with an additional ultralow dose CT (0.13±0.01 mSv) in the same session. Standard of reference (SOR) was established by consensus reading of standard dose CT by two radiologists. CAD was performed in standard dose and ultralow dose CT with two different reconstruction kernels. CAD detection rate of nodules was evaluated including subgroups of different nodule sizes (<5, 5-7, >7mm). Sensitivity was further analysed in multivariable mixed effects logistic regression.nnnRESULTSnThe SOR included 279 solid nodules (mean diameter 4.3±3.4mm, range 1-24mm). There was no significant difference in per-nodule sensitivity of CAD in standard dose with 70% compared to 68% in ultralow dose CT both overall and in different size subgroups (all p>0.05). CAD led to a significant increase of sensitivity for both radiologists reading the ultralow dose CT scans (all p<0.001). In multivariable analysis, the use of CAD (p<0.001), and nodule size (p<0.0001) were independent predictors for nodule detection, but not BMI (p=0.933) and the use of contrast agents (p=0.176).nnnCONCLUSIONSnComputer-aided detection of solid pulmonary nodules using ultralow dose CT with chest X-ray equivalent radiation dose has similar sensitivities to those from standard dose CT. Adding CAD in ultralow dose CT significantly improves the sensitivity of radiologists.

Emphysema quantification and lung volumetry in chest X-ray equivalent ultralow dose CT – Intra-individual comparison with standard dose CT

OBJECTIVESnTo determine whether ultralow dose chest CT with tin filtration can be used for emphysema quantification and lung volumetry and to assess differences in emphysema measurements and lung volume between standard dose and ultralow dose CT scans using advanced modeled iterative reconstruction (ADMIRE).nnnMETHODSn84 consecutive patients from a prospective, IRB-approved single-center study were included and underwent clinically indicated standard dose chest CT (1.7±0.6mSv) and additional single-energy ultralow dose CT (0.14±0.01mSv) at 100kV and fixed tube current at 70mAs with tin filtration in the same session. Forty of the 84 patients (48%) had no emphysema, 44 (52%) had emphysema. One radiologist performed fully automated software-based pulmonary emphysema quantification and lung volumetry of standard and ultralow dose CT with different levels of ADMIRE. Friedman test and Wilcoxon rank sum test were used for multiple comparison of emphysema and lung volume. Lung volumes were compared using the concordance correlation coefficient.nnnRESULTSnThe median low-attenuation areas (LAA) using filtered back projection (FBP) in standard dose was 4.4% and decreased to 2.6%, 2.1% and 1.8% using ADMIRE 3, 4, and 5, respectively. The median values of LAA in ultralow dose CT were 5.7%, 4.1% and 2.4% for ADMIRE 3, 4, and 5, respectively. There was no statistically significant difference between LAA in standard dose CT using FBP and ultralow dose using ADMIRE 4 (p=0.358) as well as in standard dose CT using ADMIRE 3 and ultralow dose using ADMIRE 5 (p=0.966). In comparison with standard dose FBP the concordance correlation coefficients of lung volumetry were 1.000, 0.999, and 0.999 for ADMIRE 3, 4, and 5 in standard dose, and 0.972 for ADMIRE 3, 4 and 5 in ultralow dose CT.nnnCONCLUSIONSnUltralow dose CT at chest X-ray equivalent dose levels allows for lung volumetry as well as detection and quantification of emphysema. However, longitudinal emphysema analyses should be performed with the same scan protocol and reconstruction algorithms for reproducibility.

Coronary risk assessment at X-ray dose equivalent ungated chest CT: Results of a multi-reader study

OBJECTIVESnTo determine the value of ultra-low dose chest CT with tin filtration for ordinal coronary artery calcium (CAC) risk scoring.nnnMETHODSn50 patients were prospectively included and underwent clinical standard dose chest CT (1.8±0.7mSv) and ultra-low dose CT (0.13±0.01mSv). Four radiologists estimated presence and extent of CAC.nnnRESULTSnWeighted kappa values for CAC were 0.76-0.97 in standard dose and 0.75-0.95 in ultra-low dose CT (p<0.001). Good to excellent agreement was observed for CAC ordinal risk assessment, with readers reporting identical risk in 81% of cases.nnnCONCLUSIONnCAC risk can be qualitatively assessed from X-ray dose equivalent ungated chest CT.

Value of PET/MRI for assessing tumor resectability in NSCLC - intra-individual comparison with PET/CT

OBJECTIVE:nThe purpose of this study was to compare the diagnostic accuracy of positron emission tomography (PET)/MRI with PET/CT for determining tumor resectability of non-small cell lung cancer (NSCLC).nnnMETHODS:nSequential trimodality PET/CT/MRI was performed in 36 patients referred with the clinical question of resectability assessment in NSCLC. PET/CT and PET/MR images including T1 weighted sequence (T1-Dixon) and respiration gated T2 weighted sequence (T2-Propeller) were evaluated for resectability-defining factors; i.e. longest diameter of the tumor, minimal tumor distance to the carina, mediastinal invasion, invasion of the carina, pleural infiltration, pericardial infiltration, diaphragm infiltration, presence of additional nodules.nnnRESULTS:nThere was no significant difference of maximal axial diameter measurements of the primary lung tumors and narrow limits of agreement in Bland-Altman analysis ranging from -11.1 u2009mm to + 11.8 u2009mm for T2-Propeller and from -14.3 u2009mm to + 13.8 u2009mm for T1-Dixon sequence. A high agreement of PET/MR with PET/CT for the different resectability-defining factors was observed (k from 0.769 to 1.000). There was an excellent agreement of T2-Propeller sequence and CT for additional pulmonary nodule detection (k of 0.829 and 0.833), but only a moderate and good agreement using T1-Dixon sequence (k of 0.484 and 0.722).nnnCONCLUSION:nIn NSCLC the use of PET/MRI, including a dedicated pulmonary MR imaging protocol, provides a comparable diagnostic value for determination of tumor resectability compared to PET/CT.nnnADVANCES IN KNOWLEDGE:nOur findings suggest that whole body PET/MRI can safely be used for the local staging of NSCLC patients. Further studies are warranted to determine whether it is feasible to integrate an imaging sequence in a whole body PET/MRI setting with the potential advantage of detection of liver or brain metastases.

Prognostic Value of Negative Coronary CT Angiography in Severely Obese Patients Prior to Bariatric Surgery: a Follow-Up After 6 Years

BackgroundThis study aims to determine the long-term prognostic value of coronary CT angiography (CCTA) prior to bariatric surgery in severely obese patients with a body mass index (BMI) ≥35xa0kg/m2.Material and MethodsSeventy consecutive patients undergoing cardiac CT for coronary assessment prior to bariatric surgery were prospectively included. Images were analysed for the presence of coronary calcification and for non-obstructive (<50%) or obstructive (>50% stenosis) coronary artery disease (CAD). A median clinical follow-up of 6.1xa0years in 54 patients was obtained for major adverse cardiovascular events (MACEs), defined as death, non-fatal myocardial infarction or coronary revascularisation. Weight loss and BMI decrease following bariatric surgery were recorded.ResultsThe median BMI prior to surgery was 46.9xa0kg/m2. The median percentage of excess BMI loss after surgery was 75%. CT showed coronary calcification in 26 (48%) patients, whereas 28 (52%) patients had no calcification. CCTA revealed normal coronaries in 47 (87%) and non-obstructive CAD in 7 (13%) patients. No obstructive CAD was found. All patients successfully underwent bariatric surgery, and no MACE occurred neither perioperatively nor in the follow-up period. The negative predictive value of CCTA was 100% (95% confidence interval of 90.1–100.0%).ConclusionsIn severely obese patients, the absence of obstructive CAD in cardiac CT prior to bariatric surgery with subsequently marked weight reduction has strong long-term prognostic implications for ruling out major adverse cardiac events in the postoperative period.

Diagnostic accuracy of chest X-ray dose-equivalent CT for assessing calcified atherosclerotic burden of the thoracic aorta

OBJECTIVEnTo determine the value of ultralow-dose chest CT for estimating the calcified atherosclerotic burden of the thoracic aorta using tin-filter CT and compare its diagnostic accuracy with chest direct radiography.nnnMETHODSnA total of 106 patients from a prospective, IRB-approved single-centre study were included and underwent standard dose chest CT (1.7 ± 0.7u2009mSv) by clinical indication followed by ultralow-dose CT with 100 kV and spectral shaping by a tin filter (0.13 ± 0.01u2009mSv) to achieve chest X-ray equivalent dose in the same session. Two independent radiologists reviewed the CT images, rated image quality and estimated presence and extent of calcification of aortic valve, ascending aorta and aortic arch. Conventional radiographs were also reviewed for presence of aortic calcifications.nnnRESULTSnThe sensitivity of ultralow-dose CT for the detection of calcifications of the aortic valve, ascending aorta and aortic arch was 93.5, 96.2 and 96.2%, respectively, compared with standard dose CT. The sensitivity for the detection of thoracic aortic calcification was significantly lower on chest X-ray (52.3%) compared with ultralow-dose CT (p < 0.001).nnnCONCLUSIONnA reliable estimation of calcified atherosclerotic burden of the thoracic aorta can be achieved with modern tin-filter CT at dose values comparable to chest direct radiography. Advances in knowledge: Our findings suggest that ultralow-dose CT is an excellent tool for assessing the calcified atherosclerotic burden of the thoracic aorta with higher diagnostic accuracy than conventional chest radiography and importantly without the additional cost of increased radiation dose.