Coronary Computed Tomography Angiography (CTA) Findings in COVID-19.

(1) Background: The novel SARS-CoV-2 virus infects the endothelium. Vasculitis may lead to specific coronary artery wall lesions. Coronary computed tomography angiography (CTA) imaging findings have not been systematically reported. The aim of this study was to describe a case series using CTA. (2) Methods: Patients with recent RT-PCR confirmed SARS-CoV-2 infection referred for coronary CTA for clinical indications (e.g., chest pain, troponin+, and ECG abnormalities) were included. Coronary CTA findings, such as atypical coronary lesions suggestive of vasculitis, perivascular inflammation measured by using pericoronary fat attenuation (PCAT) index, coronary artery disease, and extracoronary findings were collected. (3) Results: Results for 12 patients (54.8 ± 22 years; four females) with SARS-CoV-2 infection within 60 days (four acute care and eight stable patients) are reported. Time to positive RT-PCR was a mean of 15.1 days (range, 0-51). In four acute patients with signs of myocardial injury, plaque rupture (n = 1), hyperenhancing myocardium/MINOCA (n = 1), MINOCA (n = 1), and pericarditis with acute heart failure (LVEF 20%) (n = 1) were found. All (100%) had pericardial effusion and signs of perivascular inflammation. Among eight stable patients, pericardial effusion or perivascular inflammation were found in only two (25%). Coronary artery disease was ruled out in five (62.5%) (4) Conclusions: Coronary CTA is a useful imaging modality in the diagnostic work up of patients with COVID-19 infection, and is able to describe coronary and other cardiac abnormalities.

The interaction of lipomatous hypertrophy of the interatrial septum with pericardial adipose tissue biomarkers by computed tomography.

OBJECTIVE: Novel pericardial adipose tissue imaging biomarkers are currently under investigation for cardiovascular risk stratification. However, a specific compartment of the epicardial adipose tissue (EAT), lipomatous hypertrophy of the interatrial septum (LHIS), is included in the pericardial fat volume (PCFV) quantification software. Our aim was to evaluate LHIS by computed tomography angiography (CTA), to elaborate differences to other pericardial adipose tissue components (EAT) and paracardial adipose tissue (PAT), and to compare CT with [18F]FDG-PET. MATERIALS AND METHODS: Of 6983 patients screened who underwent coronary CTA for clinical indications, 190 patients with LHIS were finally included (age 62.8 years ± 9.6, 31.6% females, BMI 28.5 kg/cm2 ± 4.7) in our retrospective cohort study. CT images were quantified for LHIS, EAT, and PAT density (HU), and total PCFV, with and without LHIS, was calculated. CT was compared with [18F]FDG-PET if available. RESULTS: CT-density of LHIS was higher (- 22.4 HU ± 22.8) than all other pericardial adipose tissue components: EAT right and left (97.4 HU ± 13 and - 95.1 HU ± 13) PAT right and left (- 107.5 HU ± 13.4 and - 106.3 HU ± 14.5) and PCFV density -83.3 HU ± 5.6 (p < 0.001). There was a mild association between LHIS and PAT right (Beta 0.338, p = 0.006, 95% CI: 0.098-577) and PAT left (Beta 0.249, p = 0.030; 95% CI: 0.024-0.474) but not EAT right (p = 0.325) and left (p = 0.351), and not with total PCFV density (p = 0.164). The segmented LHIS volume comprised 3.01% of the total PCFV, and 4.3% (range, 2.16-11.7%) in those with LHIS > 9 mm. [18F]FDG-PET: LHIS was tracer uptake positive in 83.3% (37.5%: mild and 45.8%: minimal) of 24 patients. CONCLUSIONS: LHIS is a distinct compartment of PCFV with higher density suggesting brown fat and has no consistent association with EAT, but rather with PAT. CLINICAL RELEVANCE STATEMENT: LHIS should be recognized as a distinct compartment of the EAT, when using EAT for cardiovascular risk stratification. KEY POINTS: LHIS is currently included in EAT quantification software. LHIS density is relatively high, it is not associated with EAT, and has a high [18F]FDG-PET positive rate suggesting brown fat. LHIS is a distinct compartment of the EAT, and it may act differently as an imaging biomarker for cardiovascular risk stratification.

Lipomatous hypertrophy of the interatrial septum: a distinct adipose tissue type in COPD?

Objective: Lipomatous hypertrophy of the interatrial septum (LHIS) is a distinct section of epicardial adipose tissue. However, its association with COPD is poorly documented. Methods: Patients undergoing coronary computed tomography angiography (CTA) for clinical indications were recruited retrospectively and screened for LHIS and COPD. LHIS density and the coronary artery disease profile were quantified by CTA: stenosis severity (coronary artery disease radiological reporting system (CADRADS)), coronary artery calcium (CAC) and high-risk plaque (HRP). COPD patients with LHIS were matched for age and sex, the major cardiovascular risk factors (CVRFs), and compared to controls. Results: The prevalence of LHIS in all 5466 patients was 5.9%. 151 (72.6%) of 208 patients with COPD had LHIS. LHIS density in COPD patients was higher (-10.93 HU versus -21.1 HU; p<0.001), despite body mass index (BMI) (28.8 versus 27.01 kg·m-2; p=0.002) being lower. LHIS density was lower in obese (BMI >30 kg·m-2) patients (20.4 versus 13.6 HU; p=0.02). BMI was inversely correlated with LHIS density (BetaR -0.031; 95% CI: -0.054- -0.008; p=0.007). LHIS density was associated with COPD, but not with BMI on multivariate models. CAC and coronary stenosis severity (CADRADS and >50% stenosis) were not different (p=0.106, p=0.156 and p=0.350, respectively). HRPs were observed more frequently in COPD patients with severe Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages ≥2 (32.3% versus 20.1%; p=0.044), but not when adding mild GOLD stages. Conclusions: The prevalence of LHIS in COPD patients is high (72.6%), and the adipose tissue density is higher, indicating a higher brown fat component. In obese, patients LHIS density is lower and declines along with BMI. Coronary stenosis severity and calcium were not different; however HRPs were more frequent in severe COPD.

Does the absence of breast arterial calcification (BAC 0) rule out severe coronary artery disease? A computed tomography angiography study.

Background: Cardiovascular risk (CV)-stratification in females is challenging, and current models miss a high proportion at-risk. Breast arterial calcifications (BAC) are independent prognosticators, but their interaction with the coronary artery disease profile by computed tomography (CT) is controverse, and the role of BAC 0 unclear. Objective: to investigate the interaction of BAC with coronary CT outcomes (CAC score, coronary stenosis severity and high-risk plaque (HRP). Methods: Consecutive patients referred to mammography (MG) and coronary CTA for clinical indications within 1 year were included. Three different age groups were compared (<55 years;55-65 years;>65 years). Results: 443 patients were included. There were significant age differences for the prevalence of BAC 0 (p<0.001), BAC 0/CAC>300 AU (p=0.0023) and obstructive disease (>50% stenosis)(p=0.0048) but not for high-risk-plaque (HRP)(p=0.4905). High CAC (>300 AU) was present in only 0.82% of females with BAC 0 in less than 55 year, but significantly more often in those above 65 years (p=0.0004;OR=16.58:95% CI: 2.829-361.7) and 55 years with 12.1% and 8.4%. Obstructive coronary disease (>50% stenosis) in BAC 0 was present in 18.2%; with age-dependent differences (10.7% vs 14.7% vs 29.9%) (p=0.0003). The correlation between BAC, CAC and CADRADS was weak (r=0.246 and r=0.243, p<0.001). There was no association of BAC with HRP. Conclusion: BAC 0 rules out severe CAC >300AU in females <55 years only, but not in those above 55 years- with adherent implications for primary prevention. However, BAC 0 does not to rule out obstructive disease and high-risk plaques in symptomatic patients among all age groups.

The Neck-Persistency-Net: a three-dimensional, convolution, deep neural network aids in distinguishing vital from non-vital persistent cervical lymph nodes in advanced head and neck squamous cell carcinoma after primary concurrent radiochemotherapy.

PURPOSE: To evaluate the diagnostic performance (DP) of the high-resolution contrast computed tomography (HR-contrast-CT) based Neck-Persistency-Net in distinguishing vital from non-vital persistent cervical lymph nodes (pcLNs) in patients with advanced head and neck squamous cell carcinoma (HNSCC) following primary concurrent chemoradiotherapy (CRT) with [18F]-fluorodeoxyglucose positron emission tomography and high-resolution contrast-enhanced computed tomography ([18F]FDG-PET-CT). Furthermore, the Neck-Persistency-Net's potential to justify omitting post-CRT neck dissection (ND) without risking treatment delays or preventing unnecessary surgery was explored. METHODS: All HNSCC patients undergoing primary CRT followed by post-CRT-ND for pcLNs recorded in the institutional HNSCC registry were analyzed. The Neck-Persistency-Net DP was explored for three scenarios: balanced performance (BalPerf), optimized sensitivity (OptSens), and optimized specificity (OptSpec). Histopathology of post-CRT-ND served as a reference. RESULTS: Among 68 included patients, 11 were female and 32 had vital pcLNs. The Neck-Persistency-Net demonstrated good DP with an area under the curve of 0.82. For BalPerf, both sensitivity and specificity were 78%; for OptSens (90%), specificity was 62%; for OptSpec (95%), sensitivity was 54%. Limiting post-CRT-ND to negative results would have delayed treatment in 27%, 40%, and 7% for BalPerf, OptSens and OptSpec, respectively, versus 23% for [18F]FDG-PET-CT. Conversely, restricting post-CRT-ND to positive results would have prevented unnecessary post-CRT-ND in 78%, 60%, and 95% for BalPerf, OptSens and OptSpec, respectively, versus 55% for [18F]FDG-PET-CT. CONCLUSION: The DP of the Neck-Persistency-Net was comparable to [18F]-FDG-PET-CT. Depending on the chosen decision boundary, the potential to justify the omission of post-CRT-ND without risking treatment delays in false negative findings or reliably prevent unnecessary surgery in false positive findings outperforms the [18F]-FDG-PET-CT.

Gender differences in the diagnostic efficacy of coronary CTA: Overutilization of coronary CTA in pre- and perimenopausal females?

OBJECTIVES: Public campaigns such as the "Go-red-for-women"-initiative have raised heart-disease awareness and may trigger overutilization of coronary computed tomography angiography (CTA). Objective was to investigate the diagnostic efficacy of coronary CTA stratified by age and gender. METHODS: 1882 consecutive patients (58.9 ± 11 years;42.5% females) with low-to-intermediate pre-test-probability of coronary artery disease (CAD) referred to coronary CTA according to ESC-2019 guidelines, were included. Diagnostic efficacy was defined by the 1)negative CTA-rate 2)obstructive CAD (>50%stenosis) 3)High-risk-plaque and 4)CAC-score. RESULTS: The negative CTA rate was higher in females compared to males with 360/801 vs 292/1081 (45% vs 27%;p < 0.001). Females had a higher likelihood (OR 2.2:95%CI:1.81-2.67) of a negative CTA than males, despite they were older (p < 0.001). Obstructive disease prevalence was 25.6% and acceptable in both sexes (males vs females: 28.4% vs 21.8%;p = 0.0012). Males had more high-risk-plaque (23.6% vs 11.5%;p < 0.001). When stratifying age groups, negative CTA rate was highest in females <47 years (82.8%), but lower in males with 68.1% (p < 0.001), while obstructive disease prevalence was not different (males:6.5% vs females:4.6%:p = 0.874). Above 50 years, negative CTA rate (39.1% vs 17.6%,p < 0.001;OR 3.02:95%CI:2.381-3.823) was higher, and the obstructive disease rate was lower in females (24.8% vs 34.7%,p = 0.0003). SSPSTm(V.25,IBM) was used for statistical analysis. CONCLUSIONS: Above 50 years of age, diagnostic efficacy of coronary CTA is high in both males and females. In females <47 years, the negative CTA rate was highest with 82.8% and obstructive disease prevalence was low (4.6%), still justifying testing but recommending the use of specific tools (PROMISE minimal risk score) or other clinical tests for pre-selection.

Micro-robotic percutaneous targeting of type II endoleaks in the angio-suite.

PURPOSE: Endovascular aneurysm repair has emerged as the standard therapy for abdominal aortic aneurysms. In 9-30% of cases, retrograde filling of the aneurysm sac through patent branch arteries may result in persistence of blood flow outside the graft and within the aneurysm sac. This condition is called an endoleak type II, which may be treated by catheter-based embolization in case of continued sac enlargement. If an endovascular access is not possible, percutaneous targeting of the perfused nidus remains the only option. However, this can be very challenging due to the difficult access and deep puncture with risk of organ perforation and bleeding. Innovative targeting techniques such as robotics may provide a promising option for safe and successful targeting. METHODS: In nine consecutive patients, percutaneous embolization of type II endoleaks was performed using a table-mounted micro-robotic targeting platform. The needle path from the skin entry to the perfused nidus was planned based on the C-arm CT image data in the angio-suite. Entry point and path angle were aligned using the joystick-operated micro-robotic system under fluoroscopic control, and the coaxial needle was introduced until the target point within the perfused nidus was reached. RESULTS: All punctures were successful, and there were no puncture-related complications. The pre-operative C-arm CT was executed in 11-15 s, and pathway planning required 2-3 min. The robotic setup and sterile draping were performed in 1-2 min, and the alignment to the surgical plan took no longer than 30 s. CONCLUSION: Due to the small size, the micro-robotic platform seamlessly integrated into the routine clinical workflow in the angio-suite. It offered significant benefits to the planning and safe execution of double-angulated deeply localized targets, such as type II endoleaks.

Major cardiovascular events in patients with cardiovascular monosodium urate deposits in atherosclerotic plaques.

OBJECTIVE: To determine the association of cardiovascular atherosclerotic plaque monosodium urate deposits with the occurrence of major cardiovascular events in gout and hyperuricemia patients. METHODS: This retrospective cohort study included patients with clinically suspicion of gout, who performed a dual energy computed tomography of the affected limb and thorax between June 1st, 2012 and December 5th, 2019. Clinical and laboratory parameters were retrieved from patients charts. Established cardiovascular risk factors were evaluated. Medical history review identified the presence of major adverse cardiac events with a median follow up time of 33 months (range 0-108 months) after the performed computed tomography scan. RESULTS: Full data sets were available for 189 patients: 131 (69.3%) gout patients, 40 (21.2%) hyperuricemia patients, and 18 (9.5%) controls. Patients with cardiovascular monosodium urate deposits (n = 85/189, 45%) revealed increased serum acute phase reactants, uric acid levels and calcium scores in computed tomography compared with patients without cardiovascular monosodium urate deposits. Major adverse cardiac events were observed in 35 patients (18.5%) with a higher prevalence in those patients revealing cardiovascular monosodium urate deposits (n = 22/85, 25.9%) compared with those without cardiovascular monosodium urate deposits (n = 13/104, 12.5%, OR 2.4, p= 0.018). CONCLUSION: This is the first study demonstrating the higher hazard of major adverse cardiac events in patients with dual energy computed tomography-verified cardiovascular monosodium urate deposits. The higher prevalence of cardiac events in patients with cardiovascular monosodium urate deposits may facilitate risk stratification of gout patients, as classical cardiovascular risk scores or laboratory markers fail in their proper identification.

Photon-Counting Detector Computed Tomography (PCD-CT): A New Era for Cardiovascular Imaging? Current Status and Future Outlooks.

Photon-counting detector computed tomography (PCD-CT) represents a revolutionary new generation of computed tomography (CT) for the imaging of patients with cardiovascular diseases. Since its commercial market introduction in 2021, numerous studies have identified advantages of this new technology in the field of cardiovascular imaging, including improved image quality due to an enhanced contrast-to-noise ratio, superior spatial resolution, reduced artifacts, and a reduced radiation dose. The aim of this narrative review was to discuss the current scientific literature, and to find answers to the question of whether PCD-CT has yet led to a true step-change and significant progress in cardiovascular imaging.

CT comparison of the nasal airway anterior and posterior to the piriform aperture in patients with and without nasal obstruction.

BACKGROUND: Nasal airway stenosis may lie anterior and/or posterior to the piriform aperture. We intended to compare the nasal airway anterior and posterior to the piriform aperture in patients with and without nasal obstruction. METHODS: Segmented computed tomography cross-sectional areas of the nasal airway anterior (CT-CSAant) and posterior to the piriform aperture (at the level of the head of the inferior turbinate; CT-CSApost) were compared between patients with nasal obstruction (cases) and trauma controls. CT-CSA were approximately perpendicular to the direction of the nasal airflow. Anterior to the piriform aperture, they were tilted about 30o, 60o and 90o to the nasal floor. Posterior to the piriform aperture, they were tilted about 50o, 80o and 100o to the nasal floor. In cases, we examined the Pearson's correlation of active anterior rhinomanometry with CT-CSAant and CT-CSApost. RESULTS: Narrow and bilateral CT-CSApost were similarly large between 56 cases and 56 controls (all p > 0.2). On the contrary, narrow and bilateral CT-CSAant were significantly smaller in cases than in controls (all p < 0.001). The ratio of the size of CT-CSAant-30 to that of CT-CSApost-80 was significantly lower in cases (median: 0.84; lower to upper quartile: 0.55-1.13) than in controls (1.0; 0.88-1.16; Mann-Whitney U test; p = 0.006). Bilateral CT-CSAant correlated significantly with total inspiratory flow (all p < 0.026) in contrast to bilateral CT-CSApost (all p > 0.056). CONCLUSIONS: The nasal airway anterior to the piriform aperture was smaller in patients with nasal obstruction due to skeletal nasal stenosis than that in controls. On the contrary, the nasal airway posterior to the piriform aperture was similarly large between patients with and without nasal obstruction. Furthermore, in patients with nasal obstruction, the anterior nasal airway was narrower compared to that located posterior to it. On the contrary, control patients' anterior nasal airway was as large as the posterior one.

Prediction of high coronary artery calcium (CAC) scores from aortic arch calcification: An efficient tool for selection of non-optimal candidates for coronary CTA?

PURPOSE: Overutilization of healthcare resources is causing a high socioeconomic burden. Patients with high coronary artery calcium (CAC) scores > 1000AU are not optimal candidates for coronary CTA and better suited for other diagnostic strategies. Therefore, our objective was to evaluate whether a 4-scale aortic arch calcification severity (AoArCa) score from CT and X-Ray predicts high-CAC scores. METHODS: Patients referred to coronary/aortic CT-Angiography were enrolled. The severity of aortic arch calcification (AoArCa) was scored as grade: 0 = absent, 1 = minimal (<25 % of circumference), 2 = mild (25-50 %), 3 = moderate (50-75 %) and 4 = severe (75-100 %) on both thoracic CT and X-ray. RESULTS: In 130 patients, the absence of AoArCa by CT was highly accurate to rule out CAC > 1000AU (sens. 100 %). No or minimal AoArCa had a high NPV of 95.6 % to rule out CAC > 1000 and grade 0,1 + 2 a NPV of 86.96 %. The AUC of AoArCa by CT for predicting high CAC > 1000 was c = 0.84 (p < 0.001; 95 %CI: 0.771--0.91). For moderate-to-severe AoArCa, accuracy was c = 0.792 (p < 0.001). The intermodality agreement between CT and X-Ray based AoArCa Scores was good (r = 0.824, p < 0.001); ICC = 0.902. For X-ray, AUC was c = 0.715 to predict CAC > 1000 (p < 0.001). In regression models, only moderate-or-severe AoArCa, but not the other CVRF predicted CAC > 1000 (p < 0.001), and there was an association of the number of CVRF. CONCLUSIONS: Patients with moderate-to-severe aortic arch calcification have a high probability of CAC > 1000AU, but not those with no, minimal and mild. The absence of AoArCa rules out CAC > 1000AU. AoArCa severity may serve as valuable tool for selecting the diagnostic strategy.

Radiomic Assessment of Radiation-Induced Alterations of Skeletal Muscle Composition in Head and Neck Squamous Cell Carcinoma within the Currently Clinically Defined Optimal Time Window for Salvage Surgery-A Pilot Study.

Patients with locally advanced head and neck squamous cell carcinoma (HNSCC) frequently require primary radiochemotherapy (RCT). Despite intensity modulation, the desired radiation-induced effects observed in HNSCC may also be observed as side effects in healthy tissue, e.g., the sternocleidomastoid muscle (SCM). These side effects (e.g., tissue fibrosis) depend on the interval between the completion of RCT and restaging CT. For salvage surgery, the optimal time window for surgery is currently clinically postulated at between 6 and 12 weeks after completion of RCT. Thus, no extensive tissue fibrosis is to be expected. This interval is based on clinical studies exploring surgical complications. Studies directly exploring radiation-induced changes of the SCM in HNSCC patients are sparse. The present study quantified tissue alterations in the SCM and paravertebral musculature (PVM) after RCT, applying radiomics to determine the optimal time window for salvage surgery. Three radiomic key parameters, (1) volume, (2) mean positivity of pixels (MPP), and (3) uniformity, were extracted with mint LesionTM in the staging CTs and restaging CTs of 98 HNSCC patients. Of these, 25 were female, the mean age was 62 (±9.6) years, and 80.9% were UICC Stage IV. The mean restaging interval was 55 (±28; range 29-229) days. Only the mean volume significantly decreased after RCT, from 9.0 to 8.4 and 96.5 to 91.9 mL for the SCM and PVM, respectively (both p = 0.007, both Cohen's d = 0.28). In addition, the mean body mass index (BMI) decreased from 23.9 (±4.2) to 21.0 (±3.6) kg/m² (p < 0.001; Cohen's d = 0.9). The mean BMI decreased significantly and was correlated with the volume decrease for the SCM (r = 0.27; p = 0.007) and PVM (r = 0.41; p < 0.001). If t-test p-values were adjusted for the BMI decrease, no significant change in volumes for the SCM and PVM was observed (both p > 0.05). The present data support the clinically postulated optimal interval for salvage surgery of 6 to 12 weeks.

PBRM1 mutations might render a subtype of biliary tract cancers sensitive to drugs targeting the DNA damage repair system.

Polybromo-1 (PBRM1) loss of function mutations are present in a fraction of biliary tract cancers (BTCs). PBRM1, a subunit of the PBAF chromatin-remodeling complex, is involved in DNA damage repair. Herein, we aimed to decipher the molecular landscape of PBRM1 mutated (mut) BTCs and to define potential translational aspects. Totally, 1848 BTC samples were analyzed using next-generation DNA-sequencing and immunohistochemistry (Caris Life Sciences, Phoenix, AZ). siRNA-mediated knockdown of PBRM1 was performed in the BTC cell line EGI1 to assess the therapeutic vulnerabilities of ATR and PARP inhibitors in vitro. PBRM1 mutations were identified in 8.1% (n = 150) of BTCs and were more prevalent in intrahepatic BTCs (9.9%) compared to gallbladder cancers (6.0%) or extrahepatic BTCs (4.5%). Higher rates of co-mutations in chromatin-remodeling genes (e.g., ARID1A 31% vs. 16%) and DNA damage repair genes (e.g., ATRX 4.4% vs. 0.3%) were detected in PBRM1-mutated (mut) vs. PBRM1-wildtype (wt) BTCs. No difference in real-world overall survival was observed between PBRM1-mut and PBRM1-wt patients (HR 1.043, 95% CI 0.821-1.325, p = 0.731). In vitro, experiments suggested that PARP ± ATR inhibitors induce synthetic lethality in the PBRM1 knockdown BTC model. Our findings served as the scientific rationale for PARP inhibition in a heavily pretreated PBRM1-mut BTC patient, which induced disease control. This study represents the largest and most extensive molecular profiling study of PBRM1-mut BTCs, which in vitro sensitizes to DNA damage repair inhibiting compounds. Our findings might serve as a rationale for future testing of PARP/ATR inhibitors in PBRM1-mut BTCs.

Can ultra-low-dose computed tomography reliably diagnose and classify maxillofacial fractures in the clinical routine?

Purpose: Maxillofacial trauma predominantly affects young adults between 20 and 40 years of age. Although radioprotection is a legal requirement, the significant potential of dose reduction in computed tomography (CT) is still underused in the clinical routine. The objective of this study was to evaluate whether maxillofacial fractures can be reliably detected and classified using ultra-low-dose CT. Materials and Methods: CT images of 123 clinical cases with maxillofacial fractures were classified by two readers using the AOCOIAC software and compared with the corresponding results from post-treatment images. In group 1, consisting of 97 patients with isolated facial trauma, pre-treatment CT images at different dose levels (volumetric computed tomography dose index: ultra-low dose, 2.6 mGy; low dose, <10 mGy; and regular dose, <20 mGy) were compared with post-treatment cone-beam computed tomography (CBCT). In group 2, consisting of 31 patients with complex midface fractures, pre-treatment shock room CT images were compared with post-treatment CT at different dose levels or CBCT. All images were presented in random order and classified by 2 readers blinded to the clinical results. All cases with an unequal classification were re-evaluated. Results: In both groups, ultra-low-dose CT had no clinically relevant effect on fracture classification. Fourteen cases in group 2 showed minor differences in the classification code, which were no longer obvious after comparing the images directly to each other. Conclusion: Ultra-low-dose CT images allowed the correct diagnosis and classification of maxillofacial fractures. These results might lead to a substantial reconsideration of current reference dose levels.

Prediction of the as Low as Diagnostically Acceptable CT Dose for Identification of the Inferior Alveolar Canal Using 3D Convolutional Neural Networks with Multi-Balancing Strategies.

Ionizing radiation is necessary for diagnostic imaging and deciding the right radiation dose is extremely critical to obtain a decent quality image. However, increasing the dosage to improve the image quality has risks due to the potential harm from ionizing radiation. Thus, finding the optimal as low as diagnostically acceptable (ALADA) dosage is an open research problem that has yet to be tackled using artificial intelligence (AI) methods. This paper proposes a new multi-balancing 3D convolutional neural network methodology to build 3D multidetector computed tomography (MDCT) datasets and develop a 3D classifier model that can work properly with 3D CT scan images and balance itself over the heavy unbalanced multi-classes. The proposed models were exhaustively investigated through eighteen empirical experiments and three re-runs for clinical expert examination. As a result, it was possible to confirm that the proposed models improved the performance by an accuracy of 5% to 10% when compared to the baseline method. Furthermore, the resulting models were found to be consistent, and thus possibly applicable to different MDCT examinations and reconstruction techniques. The outcome of this paper can help radiologists to predict the suitability of CT dosages across different CT hardware devices and reconstruction algorithms. Moreover, the developed model is suitable for clinical application where the right dose needs to be predicted from numerous MDCT examinations using a certain MDCT device and reconstruction technique.

Persistent somatic symptoms are key to individual illness perception at one year after COVID-19 in a cross-sectional analysis of a prospective cohort study.

OBJECTIVE: Subjective illness perception (IP) can differ from physician's clinical assessment results. Herein, we explored patient's IP during coronavirus disease 2019 (COVID-19) recovery. METHODS: Participants of the prospective observation CovILD study (ClinicalTrials.gov: NCT04416100) with persistent somatic symptoms or cardiopulmonary findings one year after COVID-19 were analyzed (n = 74). Explanatory variables included demographic and comorbidity, COVID-19 course and one-year follow-up data of persistent somatic symptoms, physical performance, lung function testing, chest computed tomography and trans-thoracic echocardiography. Factors affecting IP (Brief Illness Perception Questionnaire) one year after COVID-19 were identified by regularized modeling and unsupervised clustering. RESULTS: In modeling, 33% of overall IP variance (R2) was attributed to fatigue intensity, reduced physical performance and persistent somatic symptom count. Overall IP was largely independent of lung and heart findings revealed by imaging and function testing. In clustering, persistent somatic symptom count (Kruskal-Wallis test: η2 = 0.31, p < .001), fatigue (η2 = 0.34, p < .001), diminished physical performance (χ2 test, Cramer V effect size statistic: V = 0.51, p < .001), dyspnea (V = 0.37, p = .006), hair loss (V = 0.57, p < .001) and sleep problems (V = 0.36, p = .008) were strongly associated with the concern, emotional representation, complaints, disease timeline and consequences IP dimensions. CONCLUSION: Persistent somatic symptoms rather than abnormalities in cardiopulmonary testing influence IP one year after COVID-19. Modifying IP represents a promising innovative approach to treatment of post-COVID-19 condition. Besides COVID-19 severity, individual IP should guide rehabilitation and psychological therapy decisions.