Comparison of dose length product and image quality of a biphasic whole-body polytrauma CT protocol with and without the automatic tube voltage selection.

BACKGROUND AND AIMS: A significant source of man-made radiation is now linked to medical devices especially X-ray imaging based ones like CT scans which expose the body to cumulative ionizing radiation and thus attendant cancer risks. The aim of this study was to determine whether using a combination of Automatic Tube Current Modulation (ATCM) and Automatic Tube Voltage Selection (ATVS) during two-phase whole-body CT (2PWBCT) examinations would reduce the radiation dose while preserving the image quality. PATIENTS AND METHODS: This was a prospective, observational, single-centre study of 127 adult patients who had undergone the 2PWBCT polytraumatic protocol. All were examined on a Somatom Drive scanner (Siemens). The patients were divided into two groups: ATCM only (42 patients) and ATCM +ATVS (85 patients). Patients' arm positions during examination and the examination dose length product (DLP) values were recorded, as well the standard deviations (SD) of the density in reference areas on CT scans for the image quality assessment. The DLP values and image quality in the groups were compared using ANOVA. RESULTS: Mean Total DLP (in mGy*cm): ATCM only: 3337 +/-797, ATCM+ATVS: 3402 +/-830; P=0.674. No effect of arm position (P=0.586). Mean density SD values in reference areas (in HU) in ATCM only: 49 +/-45, 15 +/-6, 9 +/-2, 12 +/-4, 10 +/-3, in ATCM+ATVS: 48 +/-45, 17 +/-6, 11 +/-3, 15 +/-6, 12 +/-4. SD values was higher in ATCM+ATVS group (P<0.001). CONCLUSION: Combination of ATVS and ATCM in polytraumatic 2PWBCT leads to no significant radiation load reduction compared with ATCM only but does lead to a slight degradation of image quality. The radiation load is significantly reduced if the patient has their arms behind the head when scanning, regardless of the activation of ATVS.

Variant origins of the middle colic artery from the coeliac trunk and its branches.

The middle colic artery usually arises from the superior mesenteric artery, but in rare cases it may arise from the coeliac trunk or its branches. The aim of this study was to investigate variant origins of the middle colic artery on computed tomography and anatomical dissection. Variant middle colic arteries were identified on computed tomography as part of an ongoing study investigating anatomical variations of vessels of the upper abdomen. Three-dimensional reconstructions were made to demonstrate the variant findings. Cadaveric dissections were performed as part of a routine dissection course. We report five cases of rare variant origins of the middle colic artery arising from the coeliac axis. Among these sites of origin were the coeliac trunk, the gastrosplenic trunk, the splenic artery, and the common hepatic artery. Four cases were identified on multi-detector computed tomography and one in a cadaver. In all cases, the vessels passed posterior to the body of the pancreas before entering the transverse mesocolon. Knowledge of middle colic artery variations is important to prevent inadvertent injury in digestive surgery, especially in the hepatopancreatic area. Variant origins of the middle colic artery are rare, and their knowledge is crucial to prevent unnecessary iatrogenic injury during abdominal surgery.

Unveiling the Unexpected: Why Doctors Should Look beyond the Lungs when Predicting COVID-19 Mortality.

INTRODUCTION: The main objective of this study was to identify the best combination of admission day parameters for predicting COVID-19 mortality in hospitalized patients. Furthermore, we sought to compare the predictive capacity of pulmonary parameters to that of renal parameters for mortality from COVID-19. METHODS: In this retrospective study, all patients admitted to a tertiary hospital between September 1st, 2020, and December 31st, 2020, who were clinically symptomatic and tested positive for COVID-19, were included. We gathered extensive data on patient admissions, including laboratory results, comorbidities, chest X-ray (CXR) images, and SpO2 levels, to determine their role in predicting mortality. Experienced radiologists evaluated the CXR images and assigned a score from 0 to 18 based on the severity of COVID-19 pneumonia. Further, we categorized patients into two independent groups based on their renal function using the RIFLE and KDIGO criteria to define the acute kidney injury (AKI) and chronic kidney disease (CKD) groups. The first group ("AKI&CKD") was subdivided into six subgroups: normal renal function (A); CKD grade 2+3a (B); AKI-DROP (C); CKD grade 3b (D); AKI-RISE (E); and grade 4 + 5 CKD (F). The second group was based only on estimated glomerular filtration rate (eGFR) at the admission, and thus it was divided into four grades: grade 1, grade 2+3a, grade 3b, and grade 4 + 5. RESULTS: The cohort comprised 619 patients. Patients who died during hospitalization had a significantly higher mean radiological score compared to those who survived, with a p value <0.01. Moreover, we observed that the risk for mortality was significantly increased as renal function deteriorated, as evidenced by the AKI&CKD and eGFR groups (p < 0.001 for each group). Regarding mortality prediction, the area under the curve (AUC) for renal parameters (AKI&CKD group, eGFR group, and age) was found to be superior to that of pulmonary parameters (age, radiological score, SpO2, CRP, and D-dimer) with an AUC of 0.8068 versus 0.7667. However, when renal and pulmonary parameters were combined, the AUC increased to 0.8813. Optimal parameter combinations for predicting mortality from COVID-19 were identified for three medical settings: Emergency Medical Service (EMS), the Emergency Department, and the Internal Medicine Floor. The AUC for these settings was 0.7874, 0.8614, and 0.8813, respectively. CONCLUSIONS: Our study demonstrated that selected renal parameters are superior to pulmonary parameters in predicting COVID-19 mortality for patients requiring hospitalization. When combining both renal and pulmonary factors, the predictive ability of mortality significantly improved. Additionally, we identified the optimal combination of factors for mortality prediction in three distinct settings: EMS, Emergency Department, and Internal Medicine Floor.

Segmental Versus Partial Portomesenteric Resection in Pancreatectomy for Pancreatic Cancer.

INTRODUCTION: Portomesenteric vein resections are a well-established part of pancreatectomies for advanced tumors that invade the portomesenteric axis. There are two main types of portomesenteric resections: partial resections, where only part of the venous wall is removed and segmental resection, where the full circumference of the wall is removed. The aim of this study is to compare short-term and long-term outcomes between these two techniques. METHODS: This is a single-centre retrospective study of the patients with pancreatic cancer who underwent pancreatectomy with portomesenteric vein resections between November 2009 and May 2021. RESULTS: From a total of 773 pancreatic cancer procedures, 43 (6%) patients underwent pancreatectomy with portomesenteric resections: 17 partial and 26 segmental. The overall median survival was 11 mo. For the partial portomesenteric resections, the median survival was 29 mo, and for the segmental portomesenteric resections, it was 10 mo (P = 0.019). The primary patency of the reconstructed veins after partial resection was 100% and after segmental resection was 92% (P = 0.220). Negative resection margins were achieved in 13 patients (76%) who underwent partial portomesenteric vein resection and 23 patients (88%) who underwent segmental portomesenteric vein resection. CONCLUSIONS: |Although this study is associated with worse survival, segmental resection is often the only way to safely remove pancreatic tumors with negative resection margins.

Clinical and radiological factors predicting stroke outcome after successful mechanical intervention in anterior circulation.

The recanalization effect of large-vessel occlusion (LVO) in anterior circulation is well documented but only some patients benefit from endovascular treatment. We analysed clinical and radiological factors determining clinical outcome after successful mechanical intervention. We included 146 patients from the Prague 16 study enrolled from September 2012 to December 2020, who had initial CT/CTA examination and achieved good recanalization status after mechanical intervention (TICI 2b-3). One hundred and six (73%) patients achieved a good clinical outcome (modified Rankin Scale 0-2 in 3 months). It was associated with age, leptomeningeal collaterals (LC), onset to intervention time, ASPECTS, initial NIHSS, and leukoaraiosis (LA) in univariate analysis. The regression model identified good collateral status [odds ratio (OR) 5.00, 95% confidence interval (CI) 1.91-13.08], late thrombectomy (OR 0.24, 95% CI 0.09-0.65), LA (OR 0.44, 95% CI 0.19-1.00), ASPECTS (OR 1.45, 95% CI 1.08-1.95), and NIHSS score (OR 0.86, 95% CI 0.78-0.95) as independent outcome determinants. In the late thrombectomy subgroup, 14 out of 33 patients (42%) achieved a favourable clinical outcome, none of whom with poor collateral status. The presence of LC and absence of LA predicts a good outcome in acute stroke patients after successful recanalization of LVO in anterior circulation. Late thrombectomy was associated with higher rate of unfavourable clinical outcome. Nevertheless, collateral status in this subgroup was validated as a reliable selection criterion.

Is limited-coverage CT perfusion helpful in treatment decision-making in patients with acute ischemic stroke?

BACKGROUND: The initial core infarct volume predicts treatment outcome in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). According to the literature, CT perfusion (CTP) is able to evaluate cerebral parenchymal viability and assess the initial core in AIS. We prospectively studied whether limited-coverage CTP with automated core calculation correlates with the final infarct volume on follow-up non-enhanced CT (NECT) in patients successfully treated by mechanical thrombectomy. METHODS: We enrolled 31 stroke patients (20 women aged 74.4±12.9 years and 11 men aged 66±15.4 years; median initial NIHSS score 15.5) with occlusion of the medial cerebral artery and/or the internal carotid artery that were treated by successful mechanical thrombectomy. CTP performed in a 38.6 mm slab at the level of basal ganglia was included in the CT stroke protocol, but was not used to determine indication for mechanical thrombectomy. The infarction core volume based on CTP was automatically calculated using dedicated software with a threshold defined as cerebral blood flow <30% of the value in the contralateral healthy hemisphere. The final infarction volume was measured on 24-hour follow-up NECT in the same slab with respect to CTP. Pearson and Spearman correlation coefficients and robust linear regression were used for comparison of both volumes, P values <0.05 were considered as statistically significant. RESULTS: The median time from stroke onset to CT was 77 minutes (range, 31-284 minutes), and the median time from CT to vessel recanalization was 95 minutes (range, 55-215 minutes). The mean CTP-calculated core infarct volume was 24.3±19.2 mL (median 19 mL, range 1-79 mL), while the mean final infarct volume was 21.5±39.5 mL (median 8 mL; range 0-210 mL). Only a weak relationship was found between the CTP-calculated core and final infarct volume [Pr(29) =0.32, P=0.078; rho =0.40, P=0.028]. Regression analysis showed CTP significantly overestimated lower volumes. CONCLUSIONS: In our prospective study, the infarction core calculated using limited-coverage CTP only weakly correlated with the final infarction volume measured on 24-hour follow-up NECT; moreover, CTP significantly overestimated lower volumes. Our results do not support the use of limited-coverage CTP for guiding treatment recommendations in patients with AIS.