Focus on Radiation Protection Improves Both Correct Behavior and Procedural Performance During Simulation-Based Training - A Randomized Comparison.

BACKGROUND: To explore whether simulation-based endovascular training with focus on radiation safety could improve correct behavior without jeopardizing the learning of procedural skills. METHODS: Twenty-four residents without previous endovascular experience completed 10 clinical scenarios on a virtual-reality endovascular simulator with software for peripheral endovascular interventions. Participants were randomized to receive feedback (n = 12) or not (n = 12) on radiation protection (RP) performance after each case. Expert assessments were done at the first, second, fourth, seventh, and 10th case on RP and endovascular skills (ES). Automatic simulator metrics on procedure time, contrast dose, handling errors, and estimated radiation exposure to patient and operator were registered. Outcome metrics were analyzed by two-way mixed analysis of variance pairwise comparisons with independent t-tests. Correlations were explored using Pearson's r for internal consistency reliability. RESULTS: The RP performance was similar in both groups at their first attempt (P = 0.61), but the feedback group significantly outperformed the control group over time (P < 0.001 for all comparisons). The feedback group was however slower to learn the ES at start (P = 0.047 at second performance), but after 7 attempts no difference was shown (P = 0.59). The feedback group used more time (19.5 vs. 15.3 min; P = 0.007) but less contrast (60 vs. 100 mL; P < 0.001). The number of errors was the same in both groups, but all metrics regarding radiation exposure favored the feedback group (P-values from 0.001 to 0.008). CONCLUSIONS: Simulation-based training (SBT) is effective to acquire basic endovascular intervention skills and concurrently learn RP behavior when feedback on radiation culture is provided.

Characterizing incidental mass lesions in abdominal dual-energy CT compared to conventional contrast-enhanced CT.

BACKGROUND: Incidental findings are common in abdominal computed tomography (CT) and often warrant further investigations with economic implications as well as implications for patients. PURPOSE: To evaluate the potential of dual-energy CT (DECT) in the identification and/or characterization of abdominal incidental mass lesions compared to conventional contrast-enhanced CT. MATERIAL AND METHODS: This retrospective study from a major tertiary hospital included 96 patients, who underwent contrast-enhanced abdominal DECT. Incidental lesions in adrenals, kidneys, liver, and pancreas were evaluated by two board-certified abdominal radiologists. Observer 1 only had access to standard CT reconstructions, while observer 2 had access to standard CT as well as DECT reconstructions. Disagreements were resolved by consensus review and used as a reference for observers using McNemar's test. RESULTS: Observers 1 and 2 identified a total of 40 and 34 findings, respectively. Furthermore, observer 1 registered 13 lesions requiring follow-up, of which seven (two renal and five adrenal lesions) were resolved following consensus review using DECT (P = 0.008). The inter-observer agreement was near perfect (κ = 0.82). CONCLUSION: DECT has the potential to improve the immediate characterization of incidental findings when compared to conventional CT for abdominal imaging.

Quantitative and qualitative assessments of deep learning image reconstruction in low-keV virtual monoenergetic dual-energy CT.

OBJECTIVES: To evaluate a novel deep learning image reconstruction (DLIR) technique for dual-energy CT (DECT) derived virtual monoenergetic (VM) images compared to adaptive statistical iterative reconstruction (ASIR-V) in low kiloelectron volt (keV) images. METHODS: We analyzed 30 venous phase acute abdominal DECT (80/140 kVp) scans. Data were reconstructed to ASIR-V and DLIR-High at four different keV levels (40, 50, 74, and 100) with 1- and 3-mm slice thickness. Quantitative Hounsfield unit (HU) and noise assessment were measured within the liver, aorta, fat, and muscle. Subjective assessment of image noise, sharpness, texture, and overall quality was performed by two board-certified radiologists. RESULTS: DLIR reduced image noise by 19.9-35.5% (p < 0.001) compared to ASIR-V in all reconstructions at identical keV levels. Contrast-to-noise ratio (CNR) increased by 49.2-53.2% (p < 0.001) in DLIR 40-keV images compared to ASIR-V 50 keV, while no significant difference in noise was identified except for 1 and 3 mm in aorta and for 1-mm liver measurements, where ASIR-V 50 keV showed 5.5-6.8% (p < 0.002) lower noise levels. Qualitative assessment demonstrated significant improvement particularly in 1-mm reconstructions (p < 0.001). Lastly, DLIR 40 keV demonstrated comparable or improved image quality ratings when compared to ASIR-V 50 keV (p < 0.001 to 0.22). CONCLUSION: DLIR significantly reduced image noise compared to ASIR-V. Qualitative assessment showed that DLIR significantly improved image quality particularly in thin sliced images. DLIR may facilitate 40 keV as a new standard for routine low-keV VM reconstruction in contrast-enhanced abdominal DECT. KEY POINTS: • DLIR enables 40 keV as the routine low-keV VM reconstruction. • DLIR significantly reduced image noise compared to ASIR-V, across a wide range of keV levels in VM DECT images. • In low-keV VM reconstructions, improvements in image quality using DLIR were most evident and consistent in 1-mm sliced images.

Center experience and other determinants of patient radiation exposure during prostatic artery embolization: a retrospective study in three Scandinavian centers.

OBJECTIVES: To evaluate the effects of center experience and a variety of patient- and procedure-related factors on patient radiation exposure during prostatic artery embolization (PAE) in three Scandinavian centers with different PAE protocols and levels of experience. Understanding factors that influence radiation exposure is crucial in effective patient selection and procedural planning. METHODS: Data were collected retrospectively for 352 consecutive PAE procedures from January 2015 to June 2020 at the three centers. Dose area product (DAP (Gy·cm2)) was selected as the primary outcome measure of radiation exposure. Multiple patient- and procedure-related explanatory variables were collected and correlated with the outcome variable. A multiple linear regression model was built to determine significant predictors of increased or decreased radiation exposure as reflected by DAP. RESULTS: There was considerable variation in DAP between the centers. Intended unilateral PAE (p = 0.03) and each 10 additional patients treated (p = 0.02) were significant predictors of decreased DAP. Conversely, increased patient body mass index (BMI, p < 0.001), fluoroscopy time (p < 0.001), and number of digital subtraction angiography (DSA) acquisitions (p < 0.001) were significant predictors of increased DAP. CONCLUSIONS: To minimize patient radiation exposure during PAE radiologists may, in collaboration with clinicians, consider unilateral embolization, pre-interventional CTA for procedure planning, using predominantly anteroposterior (AP) projections, and limiting the use of cone-beam CT (CBCT) and fluoroscopy. KEY POINTS: • Growing center experience and intended unilateral embolization decrease patient radiation exposure during prostatic artery embolization. • Patient BMI, fluoroscopy time, and number of DSA acquisitions are associated with increased DAP during procedures. • Large variation in radiation exposure between the centers may reflect the use of CTA before and CBCT during the procedure.

Endovascular Treatment of Chronic and Acute on Chronic Mesenteric Ischaemia: Results From a National Cohort of 245 Cases.

OBJECTIVE: Endovascular treatment of chronic mesenteric ischaemia (CMI) is linked to low early morbidity and mortality but a higher risk of recurrence than open repair. Mid and long term outcomes after endovascular treatment remain to be proven in larger series. The aim of this study was to assess short and mid term outcome after first line endovascular revascularisation of CMI and acute on chronic mesenteric ischaemia (AoCMI). METHODS: This was a prospective population and registry based cohort study supplemented by a retrospective review of medical records and imaging files. A national cohort was created based on data extracted from the Danish National Registry for Vascular Surgery (Karbase) for all patients treated endovascularly for CMI or AoCMI between 2011 and 2015 in Denmark. Survival data, bowel resection, complications, re-intervention rate, and improvement of clinical symptoms were analysed, as were potential risk factors. RESULTS: In total, 245 patients had an endovascular intervention for CMI (n = 178; 72.6%) and AoCMI (n = 67; 27.3%). One and three year survival estimates were 85% (95% confidence interval [CI] 79 - 90) and 74% (95% CI 67 - 80) in the CMI-group, and 67% (95% CI 54 - 77) and 54% (95% CI 41 - 65) in the AoCMI group. The hazard ratio for death was 1.89 (95% CI 1.23 - 2.9) for AoCMI, relative to patients with CMI. Superior mesenteric artery (SMA) stenosis, rather then occlusion, significantly increased the success of SMA recanalisation: OR 19.4 (95% CI 6.2 - 61.4) and 9.3 (95% CI 1.6 - 53.6) in the CMI and AoCMI groups, respectively. The proportion of patients reporting clinical improvement was 71% (n = 127) in the CMI group and 59% (n = 39) in the AoCMI group. Five patients (3%) in the CMI and 30 (45%) in the AoCMI groups underwent bowel resection (p < .001), and the overall length of hospital stay (LoS) was a median of two days (interquartile range [IQR] 1 - 3 days) in the CMI group and seven days (IQR 3 - 23 days) in the AoCMI group. Within the first year, re-intervention was performed in 14 patients (5.7%). CONCLUSION: First line endovascular treatment of CMI carries a three year mortality rate of 25%, and low risk of re-occurrence of symptomatic ischaemia. Relative to CMI, patients suffering AoCMI have significantly higher morbidity and mortality, more bowel resections, and longer LoS.

In Situ Vein Bypass Is Superior to Endovascular Treatment of Femoropopliteal Lesions in Chronic Limb-Threatening Ischemia.

BACKGROUND: The objective of the study was to compare bypass surgery and endovascular revascularization of the femoropopliteal segment in patients with peripheral arterial disease and critical limb-threatening ischemia (CLTI). METHODS: This is a single-center study including patients undergoing first-time lower extremity intervention with peripheral bypass surgery or percutaneous transluminal angioplasty with or without stenting (PTA/S) of the femoropopliteal segment because of CLTI from 2011 to 2015. Based on prospective entered data from the Danish Vascular Registry, the primary end points were amputation-free survival, overall mortality, and reinterventions. RESULTS: A total of 679 patients with CLTI were included of which 35% (n = 239) were treated with PTA/S, 54% (n = 363) with vein bypass, and 11% (n = 77) with synthetic bypass. After 3 years, amputation-free survival was significantly better with a vein bypass (41.8% [95% CI: 35-48.4]) than both PTA/S (29.7% (95% CI: 22.7-37)) and synthetic bypass (31.7% [95% CI: 19-45.1]). Overall, the endovascular-treated patients faced more than 50% increased risk of major amputation or death than that of a vein bypass, after adjusting for comorbidity and Trans-Atlantic Inter-Society Consensus (TASC) classification (HR: 1.56 [95% CI: 1.21-2.05]). As expected, postoperative complications, length of hospital stay, and reinterventions were more frequent in the bypass groups. CONCLUSIONS: In this nonrandomized study, autologous vein bypass was superior to both PTA/S and synthetic bypass in regard to amputation-free survival and overall mortality. Despite the increased frequency of surgical complications, a vein bypass appears justified in both shorter (TASC B-C) and longer (TASC D) femoropopliteal lesions.

Cutdown Technique is Superior to Fascial Closure for Femoral Artery Access after Elective Endovascular Aortic Repair.

OBJECTIVES: Arterial access closure after endovascular aneurysm repair (EVAR) can be achieved using three different approaches: percutaneous closure devices, surgical exposure and direct suture ("cutdown"), and the less invasive fascial closure technique. The aim of this study was to report on the intra-operative, in hospital, and three month outcome of fascial closure and cutdown, and to determine risk factors for failure. METHODS: The primary outcome was assessed in 439 groins in 225 elective EVAR patients recruited consecutively and prospectively from February 1, 2011 to August 31, 2014. During the study period, fascial closure and cutdown were first and second line closing techniques. Compared with fascial closure, procedures completed with cutdown had lower BMI, thinner subcutaneous tissue of the groin and more complex femoral anatomy. Computed tomographic angiography (CTA) and duplex ultrasound (DUS) of the groin were performed pre-operatively and three months after EVAR. Retrospective review of medical records and CTA were used to determine intra-operative and in hospital outcome, and risk factors for failure. RESULTS: In total, 64%, 33%, and 3% were completed with fascial closure, cutdown, and closure device, respectively. Intra-operative, in hospital, and three month technical success rates of fascial closure vs. cutdown were 91% (283/310 groins) vs. 99% (114/115 groins), 89% (277/310 groins) vs. 99% (114/115 groins), and 89% (275/310 groins) vs. 99% (114/115 groins) (p < .001). Wound complications within three months were infrequent for both methods. No risk factor was significantly associated with failure after fascial closure. CONCLUSION: This study shows that cutdown is superior to fascial closure for femoral artery access after elective EVAR. In acute EVAR, however, fascial closure is still considered to be a good and fast method, and it has been kept in the present authors' armamentarium for this indication.

Assessment of EVAR Competence: Validity of a Novel Rating Scale (EVARATE) in a Simulated Setting.

OBJECTIVES: The aims of this study were to investigate the validity evidence for a novel procedure specific assessment tool of competence in endovascular aortic repair (EVAR) and to establish a pass/fail level for the assessment. METHODS: Computed tomography angiography data of a 55 mm in diameter infrarenal aortic aneurysm was implemented into an endovascular simulator. Twenty-three physicians with varying EVAR experiences were video-recorded when performing a standard EVAR procedure on the simulator. Two experienced EVAR operators assessed the participants using the novel rating scale, "EndoVascular Aortic Repair Assessment of Technical Expertise" (EVARATE). Validity was studied according to the framework endorsed by the American Educational Research Association. RESULTS: The EVARATE scale had a high internal consistency (Cronbach's alpha = .90). The inter-rater reliability was acceptable (Intraclass Correlation Coefficient = .68, p = .005). Specific EVAR experience correlated significantly with the EVARATE score (Spearman's rho = .62, p = .002), but general endovascular experience did not. Consequence analysis showed that the EVARATE assessment could distinguish novices from intermediates (p < .01) and from experts (p < .001). A pass/fail score was determined using the contrasting groups' method. CONCLUSION: This paper presents the initial validity evidence for a novel procedure specific assessment tool, EVARATE, for operator competence in endovascular aortic repair investigated in a simulated setting. The assessment tool can be used to provide structured formative feedback to trainees.

Contrast Enhanced Three Dimensional Ultrasound for Intraluminal Thrombus Assessment in Abdominal Aortic Aneurysms.

OBJECTIVES: The impact of intraluminal thrombus (ILT) on abdominal aortic aneurysm (AAA) progression can be investigated non-invasively by three dimensional contrast enhanced ultrasound (3D-CEUS). The aim was to validate 3D-CEUS ILT volume and thickness measurements against computed tomography angiography (CTA), and to determine inter- and intra-operator reproducibility. METHODS: The design was for a planned comparison of 3D-CEUS and CTA and of repeated 3D-CEUS measurements in a blinded set up. Consecutive patients with asymptomatic AAA (n = 137, maximum diameter 30-55 mm) from a single centre were consecutively assessed by CTA and 3D-CEUS in a blinded setup. After exclusion of failed CTA (n = 2) and inconclusive 3D-CEUS (n = 8), 127 3D-CEUS/CTA pairs were analysed by Bland-Altman plots. 3D-CEUS inter- and intra-operator reproducibility were determined in a subgroup (n = 30) measured twice by two blinded investigators. RESULTS: In 24 of 127 (19%) patients, no ILT was found on 3D-CEUS. Intraluminal thrombus absence was confirmed by 3D-CTA analysis in all but two cases. Mean ILT volume difference between 3D-CEUS and CTA was 2.2 mL (5% of mean volume) and range of variability (ROV) amounted to ± 10.2 mL. Mean ILT thickness difference was 0.6 mm with a ROV of ± 4.6 mm 3D-CEUS inter-operator variations of ILT volume and thickness measurements were low (ROV ± 8.8 mL and ±2.9 mm, respectively). The corresponding intra-operator ROVs were ±7.5 mL and ±3.3 mm, respectively. CONCLUSIONS: 3D-CEUS demonstrated good reproducibility and a good agreement with CTA when estimating ILT volume and maximum thickness in AAA patients. It is a promising research tool to investigate potential interactions between ILT, AAA growth, and rupture.

Duplex ultrasound for identifying renal artery stenosis: direct criteria re-evaluated.

Background Renal artery duplex ultrasound (RADUS) is an established method for diagnosis of renal artery stenosis (RAS), but there is no consensus regarding optimal RADUS criteria. Purpose To define optimal cutoff values for RADUS parameters when screening for RAS using intra-arterial trans-stenotic pressure gradient measurement (PGM) as reference. Material and Methods The renal arteries of 58 consecutive patients evaluated for renovascular hypertension were examined by RADUS and PGM. Conclusive measurements with both methods were obtained in 76 arteries. Hemodynamically significant RAS was defined as PGM ≥15 mmHg and was found in 43 of the 76 arteries. RADUS parameters included renal artery peak systolic velocity (PSV) and the renal-aortic ratio (RAR) of flow velocities. Receiver operating characteristic curves (ROCs) and Youden's index were used to calculate optimal RADUS criteria for RAS. Results When traditional RADUS criteria for RAS were used, with a combination of PSV ≥180 cm/s and RAR ≥3.5, the sensitivity was 62% and the specificity was 91%. When RADUS criteria were optimized for sensitivity, then RAR ≥2.6 alone resulted in a sensitivity of 89% and a specificity of 69%. Conclusion The RAR ≥2.6 is a more sensitive criterion than traditional RADUS criteria when screening patients with clinical suspicion of RAS.

Inter- and intra-rater agreement in the assessment of the vascularity of spinal metastases using digital subtraction angiography tumor blush.

Background Preoperative embolization is based on the preoperative digital subtraction angiography (DSA) tumor blush, and as such is considered the "gold standard" for determining tumor vascularity. However, to our knowledge reliability studies evaluating vascularity ratings of DSA tumor blush in spinal metastases have not been published previously. Purpose To evaluate inter- and intra-rater agreement in the assessment of the vascularity of spinal metastases using DSA tumor blush. Material and Methods This reliability study included 46 patients with symptomatic metastatic spinal cord compression requiring surgery. DSA data stored in the hospital picture archiving and communication system (PACS) from the participants of a randomized controlled trial were used. Inter- and intra-rater agreement on vascularity assessment using DSA tumor blush according to a three-step ordinal scale was evaluated: no hypervascularity; moderate hypervascularity; and pronounced hypervascularity. The statistical analysis was based on the linear weighted kappa's for multiple raters that extend Cohen's κ. Three raters and κ = 0.2 in the null hypothesis implied that the power of the study was 0.96. Results Inter- and intra-rater agreements were moderate in rating the vascularity of spinal metastases and the agreements were significantly higher than the κ = 0.20 in the null hypothesis ( P = 0.0002 and P = 0.0001). The κ value for inter-rater agreement was 0.57 (95% confidence interval [CI], 0.41-0.72) and for intra-rater agreement 0.55 (95% CI, 0.38-0.71). Conclusion There is moderate inter-rater and intra-rater agreement in classifying the vascularity of spinal metastases on a three-step ordinal scale for DSA tumor blush.

Endovascular Aneurysm Repair Treatment of Aortoiliac Aneurysms: Can Iliac Branched Devices Prevent Gluteal Claudication?

PURPOSE: To compare the risk of gluteal claudication after endovascular aneurysm repair (EVAR) of aortoiliac aneurysms by interventional exclusion of the internal iliac artery (IIA) with plugs or coils versus a branch iliac device to maintain pelvic blood supply and to identify risk factors for postoperative gluteal claudication. MATERIALS AND METHODS: A retrospective analysis of a prospectively collected data set included patients with aortoiliac aneurysms treated with EVAR from January 2007 to December 2013 at a tertiary referral vascular unit. Descriptive and procedural data were obtained from a database of prospectively enrolled patients. Medical records of 112 consecutive patients treated with EVAR were scrutinized for graft-related adverse events and pelvic ischemia. The occurrence of gluteal claudication was determined from medical records. RESULTS: Iliac occlusion was performed in 115 limbs, and a branch iliac device was placed in 25 limbs. Gluteal claudication developed in 38% of limbs treated with IIA exclusion but in none of the limbs treated with branch iliac devices (P < .001). Procedure time, fluoroscopy time, and use of iodine contrast material did not differ between the two groups. The incidence of gluteal claudication was higher when coils rather than plugs were used for embolization of the IIA before EVAR (P = .002). CONCLUSIONS: The findings suggest that the use of a branch iliac device significantly reduces the risk of gluteal claudication after EVAR of aortoiliac aneurysm.

ADRB2 gly16gly Genotype, Cardiac Output, and Cerebral Oxygenation in Patients Undergoing Anesthesia for Abdominal Aortic Aneurysm Surgery.

BACKGROUND: Gly16arg polymorphism of the adrenergic ß2-receptor is associated with the elevated cardiac output (Q) in healthy gly16-homozygotic subjects. We questioned whether this polymorphism also affects Q and regional cerebral oxygen saturation (SCO2) during anesthesia in vascular surgical patients. METHODS: One hundred sixty-eight patients (age 71 ± 6 years) admitted for elective surgery were included. Cardiovascular variables were determined before and during anesthesia by intravascular pulse contour analysis (Nexfin) and SCO2 by cerebral oximetry (INVOS 5100C). Genotyping was performed with the TaqMan assay. RESULTS: Before anesthesia, Q and SCO2 were 4.7 ± 1.2 L/min and 66% ± 8%, respectively, and linearly correlated (r = 0.35, P < .0001). In patients with the gly16gly genotype baseline, Q was approximately 0.4 L/min greater than in arg16 carriers (CI95: 0.0-0.8, Pt test = .03), but during anesthesia, the difference was 0.3 L/min (Pmixed-model = .07). Post hoc analysis revealed the change in SCO2 from baseline to the induction of anesthesia to be on average 2% greater in gly16gly homozygotes than in arg16 patients when adjusted for the change in Q (P = .03; CI95: 0.2-4.0%). CONCLUSIONS: This study suggests that the ß2-adrenoceptor gly16gly genotype is associated with the elevated resting Q. An interesting trend to greater frontal lobe oxygenation at induction of anesthesia in patients with gly16gly genotype was found, but because of insufficient sample size and lack of PCO2 control throughout the measurements, the presented data may only serve as the hypothesis generating for future studies. The confidence limits indicate that the magnitude of the effects may range from clinically insignificant to potentially important.

Combined surgical and catheter-based treatment of extensive thoracic aortic aneurysm and aortic valve stenosis.

An extensive thoracic aortic aneurysm (TAA) is a potentially life-threatening condition and remains a technical challenge to surgeons. Over the past decade, repair of aortic arch aneurysms has been accomplished using both hybrid (open and endovascular) and totally endovascular techniques. Thoracic endovascular aneurysm repair (TEVAR) has changed and extended management options in thoracic aorta disease, including in those patients deemed unfit or unsuitable for open surgery. Accordingly, transcatheter aortic valve replacement (TAVR) is increasingly used to treat patients with symptomatic severe aortic valve stenosis (AS) who are considered at high risk for surgical aortic valve replacement. In this report, we describe the combined surgical and catheter-based treatment of an extensive TAA and AS. To our knowledge, this is the first report of hybrid TAA repair combined with TAVR.

Preoperative embolization in surgical treatment of spinal metastases: single-blind, randomized controlled clinical trial of efficacy in decreasing intraoperative blood loss.

PURPOSE: To assess whether preoperative transcatheter arterial embolization of spinal metastases reduces blood loss, the need for transfusion with allogeneic red blood cells (RBCs), and surgery time in the surgical treatment of patients with symptomatic metastatic spinal cord compression. MATERIALS AND METHODS: This single-blind, randomized (1:1), controlled, parallel-group, single-center trial was approved by the Danish National Committee on Biomedical Research Ethics and was conducted from May 2011-March 2013. Participants (N = 45) were scheduled for decompression and posterior thoracic/lumbar spinal instrumentation and randomly assigned to either preoperative embolization (n = 23) or a control group (n = 22). The primary outcome was intraoperative blood loss. Secondary outcomes were perioperative blood loss, allogeneic RBC transfusion, and surgery time. Analyses were performed by intention-to-treat. RESULTS: The intention-to-treat analysis included 45 patients. Mean intraoperative blood loss did not differ significantly (P = .270) between the embolization group (618 mL [SD, 282 mL]) and the control group (735 mL [SD, 415 mL]). There was also no significant difference in allogeneic RBC transfusion (P = .243). Surgery time was significantly shorter in the embolization group (P = .031): median 90 minutes (range, 54-252 min) versus 124 minutes (range, 80-183 min). The subanalysis of hypervascular metastases revealed a significant (P = .041) reduction in blood loss in the embolization group: 645 mL (SD, 289 mL) versus 902 mL (SD, 416 mL). CONCLUSIONS: Preoperative embolization in patients with symptomatic spinal metastasis independent of primary tumor diagnosis did not reduce intraoperative blood loss and allogeneic RBC transfusion significantly but did reduce the surgery time. A small reduction of intraoperative blood loss was shown in hypervascular metastases.

A comparative study of strain and shear-wave elastography in an elasticity phantom.

OBJECTIVE. The purpose of this study was to assess the diagnostic accuracy of strain and shear-wave elastography for determining targets of varying stiffness in a phantom. The effect of target diameter on elastographic assessments and the effect of depth on shear-wave velocity were also investigated. MATERIALS AND METHODS. We examined 20 targets of varying diameters (2.5-16.7 mm) and stiffnesses (8, 14, 45, and 80 kPa) with a 4-9-MHz linear-array transducer. Targets were evaluated 10 times with three different methods-shear-wave elastography, strain ratio, and strain histogram analysis-yielding 600 evaluations. AUCs were calculated for data divided between different stiffnesses. A 1.5-6-MHz curved-array transducer was used to assess the effect of depth (3.5 vs 6 cm) on shear-wave elastography in 80 scans. Mixed model analysis was performed to assess the effect of target diameter and depth. RESULTS. Strain ratio and strain histogram AUCs were higher than the shear-wave velocity AUC (p < 0.001) in data divided as 80 versus 45, 14, and 8 kPa. In data divided as 80 and 45 versus 14 and 8 kPa, the methods were equal (p = 0.959 and p = 1.000, respectively). Strain ratios were superior (p = 0.030), whereas strain histograms were not significantly better (p = 0.083) than shear-wave elastography in data divided as 80, 45, and 14 versus 8 kPa. Target diameter had an effect on all three methods (p = 0.001). Depth had an effect on shear-wave velocity (p = 0.001). CONCLUSION. The ability to discern different target stiffnesses varies between shear-wave and strain elastography. Target diameter affected all methods. Shear-wave elastography is affected by target depth.

Preoperative methylprednisolone enhances recovery after endovascular aortic repair: a randomized, double-blind, placebo-controlled clinical trial.

OBJECTIVE: To evaluate effects of preoperative high-dose glucocorticoid on the inflammatory response and recovery after endovascular aortic aneurysm repair (EVAR). BACKGROUND: The postimplantation syndrome after EVAR may delay recovery due to the release of proinflammatory mediators. Glucocorticoids may reduce postoperative inflammatory responses and enhance recovery, but with limited information on EVAR. METHODS: A single-center, randomized, double-blind, placebo-controlled trial of 153 patients undergoing elective EVAR between November 2009 and January 2013. Patients received 30 mg/kg of methylprednisolone (MP) (n = 77) or placebo (n = 76) preoperatively. Primary outcome was a modified version of the systemic inflammatory response syndrome. Secondary outcome measures were the effect on inflammatory biomarkers, morbidity, and time to meet discharge criteria. RESULTS: Of 153 randomized patients, 150 (98%) were evaluated for the primary outcome. MP reduced systemic inflammatory response syndrome from 92% to 27% (P < 0.0001) (number needed to treat = 1.5), maximal plasma interleukin 6 from 186 pg/mL [interquartile range (IQR) = 113-261 pg/mL] to 20 pg/mL (IQR = 11-28 pg/mL) (P < 0.001) and fulfillment of discharge criteria was shorter [2 days (IQR = 2-4 days) vs 3 days (IQR = 3-4 days)] (P < 0.001). C-reactive protein, temperature, interleukin 8, and soluble tumor necrosis factor receptor were also reduced (P < 0.001) by MP. Myeloperoxidase, D-dimer, and matrix metalloproteinase 9 were not modified. No differences in 30-day medical (23% vs 36%) (P = 0.1) or surgical (20% vs 21%) morbidity were found in the active group versus the placebo group. CONCLUSIONS: Preoperative MP attenuates the inflammatory response with a faster recovery after EVAR for abdominal aortic aneurysms. Further safety and dose-response studies are required to allow recommendations for general practice. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00989729.

Management of placenta percreta: a review of published cases.

Publications on abnormally invasive placenta in general report what can be considered a mixture of the conditions true accreta, increta and percreta varieties. The aim of this review was to identify all published cases of the most severe condition, placenta percreta in order to describe complications associated with the three commonly used surgical strategies: local resection, hysterectomy or leaving the placenta in situ, and to describe the outcome, with respect to blood loss and transfusion requirements, with the different endovascular interventions that may be used as adjuncts in the management of the conditions. A PubMed search was performed in April 2013 and the final review included 119 published placenta percreta cases. Conservative management, where the placenta is left in situ for resorption, seems to be associated with severe long-term complications of hemorrhage and infections, including a 58% risk that a hysterectomy will eventually be needed up till nine months after the delivery. Local resection seems to be associated with fewer complications within 24 h postoperatively compared with hysterectomy or leaving the placenta in situ. A selection bias in the direction of less severe cases for the local resection technique might in part explain the lower complication rates with that approach. Future prospective data collection activities should include intended as well as actual management, and long-term follow-up of all cases is of vital importance.

Perioperative blood transfusion does not decrease survival after surgical treatment of spinal metastases.

PURPOSE: To assess whether perioperative allogenic blood transfusions in patients undergoing surgical treatment for spinal metastases independently influence patient survival. METHODS: A retrospective study including 170 consecutive patients undergoing surgical treatment for spinal metastases in 2009 and 2010 at a tertiary referral center. Variables related to postoperative survival were all included in the same multivariable logistic regression analysis with either 3- or 12-month survival as the dependent variable. The independent variables were: transfusion of allogenic red blood cells, age at surgery, gender, preoperative hemoglobin, revised Tokuhashi score and no. of instrumented levels. RESULTS: Perioperative allogenic blood transfusion of 1-2 units was associated with increased 12-month survival [p = 0.049, odds ratio 2.619 (confidence interval 1.004-6.831)], but not with 3-month survival. Larger transfusion volumes did not significantly influence survival. CONCLUSION: The results of the present study support that perioperative blood transfusion of <5 units does not decrease survival in patients operated for spinal metastases. Transfusion of 1-2 units seems to be associated with increased 12-month survival. Future studies should assess if a liberal transfusion regime can be applied to this group of patients; thereby, prioritizing early postoperative mobilization.

Copenhagen Mesenteric stent study (COMESS)-a randomized trial of stent versus covered stent treatment for chronic mesenteric ischemia.

BACKGROUND: Current management of mesenteric ischemia is primarily endovascular stent treatment. Typical CMI symptoms are postprandial abdominal pain, food fear, weight loss, and diarrhea. Revascularization is often necessary, as mesenteric ischemia may progress to bowel necrosis and death if left untreated. This study aims to compare the outcome using bare metal stent (BMS) or covered stent (CS) in the endovascular treatment of chronic and acute on chronic mesenteric ischemia. METHODS: This is an investigator-driven, prospective, randomized, single-blinded, and single-center, national cohort study at the Copenhagen University Hospital, Denmark. A total of 98 patients with chronic mesenteric ischemia (CMI) and acute-on-chronic mesenteric ischemia (AoCMI) will be randomized to treatment with either BeSmooth BMS (Bentley Innomed GmbH) or BeGraft CS (Bentley Innomed GmbH). Randomization occurs intraoperatively after lesion crossing. DISCUSSION: There is currently no published data from prospective controlled trials regarding the preferred type of stent used for the treatment of chronic and acute-on-chronic mesenteric ischemia. This trial will evaluate the short- and long-term outcome of BMS versus CS when treating CMI and AoCMI, as well as the benefit of a more intense postoperative surveillance program. TRIAL REGISTRATION: ClinicalTrials.gov NCT05244629. Registered on February 8, 2022.