Endovascular interventions (EVI) are increasingly performed as minimally-invasive alternatives to surgery and have many advantages, including a decreased need for general anesthesia. However, EVI can ...be stressful for patients and often lead to anxiety and pain related to the procedure. The use of local anesthetics, anxiolytics, and analgesic drugs can help avoid general anesthesia. Nevertheless, these drugs have potential side effects. Alternative nonpharmacological therapies can improve patients' experience during conscious interventions and reduce the need for additional medications. The added value of virtually augmented self-hypnosis (VA-HYPO) and its potential to reduce pain and anxiety during peripheral and visceral arterial and venous EVI is unknown. This is a prospective two-arm trial designed to randomize 100 patients in two groups according to the use or not of VA-HYPO during peripheral EVI as a complementary nonpharmacological technique to improve patient comfort. The main objective is to compare per-procedural anxiety, and the secondary aim is to compare the rated per-procedural pain in both groups. The potential significance is that VA-HYPO may improve patients' experience during peripheral and visceral arterial and venous EVI and other minimally invasive interventions performed under local anesthesia. Trial registration: Our study is registered on clinicaltrials.gov, with trial registration number: NCT04561596.
Computed tomography pulmonary angiography (CTPA) has not only become the method of choice for diagnosing acute pulmonary embolism (PE), it also allows for risk stratification of patients with PE. To ...date, no study has specifically examined the predictive value of CTPA findings to assess short-term prognosis in elderly patients with acute PE who are particularly vulnerable to adverse outcomes.
We studied 291 patients aged ≥65 years with acute symptomatic PE in a prospective multicenter cohort. Outcomes were 90-day overall and PE-related mortality, recurrent venous thromboembolism (VTE), and length of hospital stay (LOS). We examined associations of the computed tomography obstruction index (CTOI) and the right ventricular (RV) to left ventricular (LV) diameter ratio with mortality and VTE recurrence using survival analysis, adjusting for provoked VTE, Pulmonary Embolism Severity Index (PESI), and anticoagulation as a time-varying covariate.
Overall, 15 patients died within 90 days. There was no association between the CTOI and 90-day overall mortality (adjusted hazard ratio per 10% CTOI increase 0.92; 95% confidence interval CI 0.70-1.21; P = 0.54), but between the CTOI and PE-related 90-day mortality (adjusted sub-hazard ratio per 10% CTOI increase 1.36; 95% CI 1.03-1.81; P = 0.03). The RV/LV diameter ratio was neither associated with overall nor PE-related 90-day mortality. The CTOI and the RV/LV diameter ratio were significantly associated with VTE recurrence and LOS.
In elderly patients with acute PE, the CTOI was associated with PE-related 90-day mortality but not with overall 90-day mortality. The RV/LV diameter ratio did not predict mortality. Both measures predicted VTE recurrence and LOS. The evaluated CTPA findings do not appear to offer any advantage over the PESI in terms of mortality prediction.
Objectives
To quantitatively evaluate the impact of virtual monochromatic images (VMI) on reduced-iodine-dose dual-energy coronary computed tomography angiography (CCTA) in terms of coronary lumen ...segmentation in vitro, and secondly to assess the image quality in vivo, compared with conventional CT obtained with regular iodine dose.
Materials and methods
A phantom simulating regular and reduced iodine injection was used to determine the accuracy and precision of lumen area segmentation for various VMI energy levels. We retrospectively included 203 patients from December 2017 to August 2018 (mean age, 51.7 ± 16.8 years) who underwent CCTA using either standard (group A,
n
= 103) or reduced (group B,
n
= 100) iodine doses. Conventional images (group A) were qualitatively and quantitatively compared with 55-keV VMI (group B). We recorded the location of venous catheters.
Results
In vitro, VMI outperformed conventional CT, with a segmentation accuracy of 0.998 vs. 1.684 mm
2
, respectively (
p
< 0.001), and a precision of 0.982 vs. 1.229 mm
2
, respectively (
p
< 0.001), in simulated overweight adult subjects. In vivo, the rate of diagnostic CCTA in groups A and B was 88.4% (
n
= 91/103) vs. 89% (
n
= 89/100), respectively, and noninferiority of protocol B was inferred. Contrast-to-noise ratios (CNR) of lumen versus fat and muscle were higher in group B (
p
< 0.001) and comparable for lumen versus calcium (
p
= 0.423). Venous catheters were more often placed on the forearm or hand in group B (
p
< 0.001).
Conclusion
In vitro, low-keV VMI improve vessel area segmentation. In vivo, low-keV VMI allows for a 40% iodine dose and injection rate reduction while maintaining diagnostic image quality and improves the CNR between lumen versus fat and muscle.
Key Points
• Dual-energy coronary CT angiography is becoming increasingly available and might help improve patient management.
• Compared with regular-iodine-dose coronary CT angiography, reduced-iodine-dose dual-energy CT with low-keV monochromatic image reconstructions performed better in phantom-based vessel cross-sectional segmentation and proved to be noninferior in vivo.
• Patients receiving reduced-iodine-dose dual-energy coronary CT angiography often had the venous catheter placed on the forearm or wrist without compromising image quality.
In this paper, a wideband antenna is proposed for ultra-wideband microwave imaging applications. The antenna is comprised of a tapered slot ground, a rectangular slotted patch and four star-shaped ...parasitic components. The added slotted patch is shown to be effective in improving the bandwidth and gain. The proposed antenna system provides a realized gain of 6 dBi, an efficiency of around 80% on the radiation bandwidth, and a wide impedance bandwidth (S11 < -10 dB) of 6.3 GHz (from 3.8 to 10.1 GHz). This supports a true wideband operation. Furthermore, the fidelity factor for face-to-face (FtF) direction is 91.6%, and for side by side (SbS) is 91.2%. This proves the excellent directionality and less signal distortion of the designed antenna. These high figures establish the potential use of the proposed antenna for imaging. A heterogeneous breast phantom with dielectric characteristics identical to actual breast tissue with the presence of tumors was constructed for experimental validation. An antenna array of the proposed antenna element was situated over an artificial breast to collect reflected and transmitted waves for tumor characterization. Finally, an imaging algorithm was used to process the retrieved data to recreate the image in order to detect the undesirable tumor object inside the breast phantom.
Intracavitary electrocardiography is an accurate guidance technique for peripherally inserted central catheters (PICC) tip location that is spreading widely among providers using non x-ray-based ...facilities. The principle behind this technology relies on the transmission of the electrocardiographic signal at the tip of the catheter and its use as an internal mobile electrode, allowing the system to identify the cavo-atrial junction (CAJ) through internal P-wave amplitude modulations. The gain in popularity of intracavitary electrography and its large diffusion have led manufacturers to offer various devices with heterogeneous properties, among which clinician who place PICCs have to choose. It is therefore important to understand differences between available techniques and devices. The potential impact might not only affect availability and costs but also the clinical impact through advantages and limitations regarding electric signal transmission PICC selection. Current perspectives on intracavitary electrocardiography will also be discussed, to give the reader a global view of the management of electrocardiographically guided PICCs, especially in an environment without x-ray support.
Objectives
To evaluate the diagnostic utility of multiphase postmortem CT angiography (PMCTA) to detect plaque enhancement as a surrogate marker of inflammation, using fatal coronary plaques obtained ...from autopsies following sudden cardiac death.
Methods
In this retrospective study, we included 35 cases (12 women, 34%; median IQR age, 52 11 years), with autopsy-proven coronary thrombosis, histological examination, and multiphase PMCTA. Two radiologists blinded towards histological findings assessed PMCTA for plaque enhancement of the culprit lesion in consensus. Two forensic pathologists determined the culprit lesion and assessed histological samples in consensus. Cases with concomitant vasa vasorum density increase and intraplaque and periadventital inflammation were considered positive for plaque inflammation. Finally, we correlated radiology and pathology findings.
Results
All 35 cases had histological evidence of atherosclerotic plaque disruption and thrombosis; 30 (85.7%) had plaque inflammation. Plaque enhancement at multiphase PMCTA was reported in 21 (60%) and resulted in a PPV of 95.2% (77.3–99.2%) and an NPV of 28.6% (17–43.9%). Median histological ratings indicated higher intraplaque inflammation (
p
= .024) and vasa vasorum density (
p
= .032) in plaques with enhancement. We found no evidence of a difference in adventitial inflammation between CT-negative and CT-positive plaques (
p
= .211).
Conclusions
Plaque enhancement was found in 2/3 of fatal atherothrombotic occlusions at coronary postmortem CT angiography. Furthermore, plaque enhancement correlated with histopathological plaque inflammation and increased vasa vasorum density. Plaque enhancement on multiphase CT angiography could potentially serve as a noninvasive marker of inflammation in high-risk populations.
Clinical relevance statement
Phenotyping coronary plaque more comprehensively is one of the principal challenges cardiac imaging is facing. Translating our ex vivo findings of CT-based plaque inflammation assessment into clinical studies might help pave the way in defining high-risk plaque better.
Key Points
•
Most thrombosed coronary plaques leading to fatality in our series had histological signs of inflammation.
•
Multiphase postmortem CT angiography can provide a noninvasive interrogation of plaque inflammation through contrast enhancement.
•
Atherosclerotic plaque enhancement at multiphase postmortem CT angiography correlated with histopathological signs of plaque inflammation and could potentially serve as an imaging biological marker of plaque vulnerability.
PDF
