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2021 ◽  
Author(s):  
Mahshad Javidan ◽  
Hadi Esfandi ◽  
Ramin Pashaie

Author(s):  
Anna-Claire Marrone ◽  
Gemma Morrow ◽  
Michael Kelleman ◽  
Joan Lipinski ◽  
William Border ◽  
...  

Background: The risks for exposure to suspected and confirmed COVID patients during transthoracic echocardiograms (TTE) led us to endorse an abbreviated scanning protocol. We sought to determine whether this impacted the TTE quality measures that were being followed in our lab prior to the pandemic. Methods: Data were collected retrospectively for four quality measures reported quarterly in our lab: Diagnostic error rate, Appropriateness of initial outpatient TTE orders and American College of Cardiology Initial TTE Image Quality Metric (IQM) and Comprehensive Exam Metric (CEM). These measures were compared between two similar quarters in pre-COVID (2019) and COVID era (2020) for non-COVID patients. Additionally, IQM and CEM of 40 TTEs in COVID patients were compared with those of non-COVID patients. Results: The IQM and CEM scored significantly less in COVID patients compared to non-COVID patients (p<0.001 for both). Systemic and pulmonary veins, pulmonary arteries and arch were not adequately evaluated in COVID patients. In non-COVID patients, there were no significant differences in the IQM and diagnostic error rate but improvement in CEM and appropriateness of TTE orders from 2019 to 2020. There was no significant change in TTEs ordered for Rarely Appropriate indications, but the proportion of those ordered for syncope, palpitations and arrhythmias increased in 2020 compared to 2019. Conclusion: Though the diagnostic error rate did not change during the pandemic and the proportion of TTEs ordered for appropriate indications increased, the imaging quality in COVID patients was significantly compromised, especially for systemic and pulmonary veins, pulmonary arteries, and arch.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Guilherme D. Kolinger ◽  
David Vállez García ◽  
Talakad G. Lohith ◽  
Eric D. Hostetler ◽  
Cyrille Sur ◽  
...  

Abstract Background [18F]MK-6240 is a PET tracer with sub-nanomolar affinity for neurofibrillary tangles. Therefore, tau quantification is possible with [18F]MK-6240 PET/CT scans, and it can be used for assessment of Alzheimer’s disease. However, long acquisition scans are required to provide fully quantitative estimates of pharmacokinetic parameters. Therefore, on the present study, dual-time-window (DTW) acquisitions was simulated to reduce PET/CT acquisition time, while taking into consideration perfusion changes and possible scanning protocol non-compliance. To that end, time activity curves (TACs) representing a 120-min acquisition (TAC120) were simulated using a two-tissue compartment model with metabolite corrected arterial input function from 90-min dynamic [18F]MK-6240 PET scans of three healthy control subjects and five subjects with mild cognitive impairment or Alzheimer’s disease. Therefore, TACs corresponding to different levels of specific binding were generated and then various perfusion changes were simulated. Next, DTW acquisitions were simulated consisting of an acquisition starting at tracer injection, a break and a second acquisition starting at 90 min post-injection. Finally, non-compliance with the PET/CT scanning protocol were simulated to assess its impact on quantification. All TACs were quantified using reference Logan’s distribution volume ratio (DVR) and standardized uptake value ratio (SUVR90) using the cerebellar cortex as reference region. Results It was found that DVR from a DTW protocol with a 60-min break between two 30-min dynamic scans closely approximates the DVR from the uninterrupted TAC120, with a regional bias smaller than 2.5%. Moreover, SUVR90 estimates were more susceptible (regional bias ≤ 19%) to changes in perfusion compared to DVR from a DTW TAC (regional bias ≤ 10%). Similarly, SUVR90 was affected by late-time scanning protocol delays reaching an increase of 8% for a 20-min delay, while DVR was not affected (regional bias < 1.5%) by DTW protocol non-compliance. Conclusions Therefore, such DTW protocol has the potential to increase patient comfort and throughput without compromising quantitative accuracy and is more reliable against SUVR in terms of perfusion changes and protocol deviations, which could prove beneficial for drug effect assessment and patient follow-up using longitudinal [18F]MK-6240 PET imaging.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Ayman G. Elnahry ◽  
Gehad A. Elnahry

Background. Diabetic macular edema (DME) is a major cause of vision loss in diabetics that is currently mainly treated by antivascular endothelial growth factor (VEGF) agents. The effect of these agents on macular perfusion (MP) is a current concern. Optical coherence tomography angiography (OCTA) is an imaging modality that allows noninvasive high-resolution retinal microvasculature imaging. Several recent studies evaluated the effect of anti-VEGF agents on the MP of DME patients using OCTA. Our aim is to provide a systematic review of these studies. Methods. Multiple databases were searched including PubMed, Ovid Medline, EMBASE, and Google Scholar for relevant studies published between January 2016 and November 2020 which were included in this review. Studies were compared regarding their design, the number of included patients, the machine and scanning protocol used, the inclusion and exclusion criteria, the number of injections given, the type of anti-VEGF agent used, the outcome measures assessed, and the effect of injections on different MP parameters. Results. A total of 16 studies were included. The studies assessed various OCTA parameters that define MP including the foveal avascular zone area and superficial and deep vascular density and yielded conflicting results. Seven studies showed stable or improved MP following treatment, while 7 studies showed worsening MP following treatment, and 2 studies showed inconclusive results. This could have been due to differences in study design, inclusion criteria, type of anti-VEGF agents used, treatment duration, and methods of image analysis and vascular density quantification. All identified studies were noncomparative case series, and 14 of them (87.5%) used the RTVue XR Avanti OCTA machine. Only one study compared OCTA to fluorescein angiography findings. Conclusion. Analysis of MP changes following VEGF inhibition for DME could benefit from a unified scanning protocol and analysis approach that uses similar study designs to eliminate potential sources of bias. This may provide more definitive conclusions regarding the effect of treatment on MP.


RMD Open ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. e001581
Author(s):  
Nina Krafft Sande ◽  
Pernille Bøyesen ◽  
Anna-Birgitte Aga ◽  
Hilde Berner Hammer ◽  
Berit Flatø ◽  
...  

ObjectiveTo develop an ultrasonographic image acquisition protocol and a joint-specific scoring system for synovitis with reference atlas in patients with juvenile idiopathic arthritis (JIA) and to assess the reliability of the system.MethodsSeven rheumatologists with extensive ultrasound experience developed a scanning protocol and a semiquantitative joint-specific scoring system for B-mode (BM) synovitis for the elbow, wrist, metacarpophalangeal 2–3, proximal interphalangeal 2–3, hip, knee, ankle and metatarsophalangeal 2–3 joints. An ultrasonographic reference atlas for BM synovitis, divided in four age groups (2–4, 5–8, 9–12, 13–18 years), and power Doppler (PD) activity was then developed. Reliability was assessed for all joints on still images and in a live exercise including 10 patients with JIA, calculated by intraclass correlation coefficient (ICC) and weighted kappa.ResultsA scanning protocol and scoring system for multiple joints with reference atlas composed of images with four different score levels for BM and PD were developed. Still image scoring for BM synovitis on joint level showed good to excellent intra-reader reliability (ICC/kappa ranges: 0.75–0.95/0.63–0.91) and moderate to excellent inter-reader reliability (ICC/kappa ranges: 0.89–0.99/0.50–0.91). Still image scoring for PD activity showed excellent intra-reader and inter-reader reliability (ICC/kappa: 0.96/0.91 and ICC/kappa: 0.97/0.80, respectively). In the live scoring, inter-reader reliability (ICC/kappa) was moderate to excellent for BM synovitis (0.94/0.51) and PD activity (0.91/0.60).ConclusionAn ultrasonographic image acquisition protocol and joint-specific scoring system with reference atlas were developed and demonstrated moderate to excellent reliability for scoring of synovitis in patients with JIA. This can be a valuable tool in clinical practice and future research.


Author(s):  
Tobias Franiel ◽  
Patrick Asbach ◽  
Dirk Beyersdorff ◽  
Dirk Blondin ◽  
Sascha Kaufmann ◽  
...  

The Working Group Uroradiology and Urogenital Diagnosis of the German Roentgen Society (DRG) revised and updated the recommendations for preparation and scanning protocol of the multiparametric MRI of the Prostate in a consensus process and harmonized it with the managing board of German Roentgen Society and Professional Association of the German Radiologist (BDR e. V.). These detailed recommendation define the referenced “validated quality standards” of the German S3-Guideline Prostate Cancer and describe in detail the topic 1. anamnestic datas, 2. termination of examinations and preparation of examinations, 3. examination protocol and 4. MRI-(in-bore)-biopsy. Key Points: Citation Format


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