The application value of low-dose CT scan in pregnant women with COVID-19

COVID-19 infection during the third trimester of pregnancy: Current clinical dilemmas

Funding Acknowledgements Type of funding sources: None. Background Coronary artery calcium (CAC) is a well-known predictor of major adverse cardiac events and is scored manually from dedicated, ECG-triggered CT scans. In the present study, we investigated the accuracy of risk categorisation based on visual and automatic AI calcium scoring from low dose CT (LDCT) scans and dedicated Calcium Score CT (CSCT) scans. Purpose To assess the agreement of risk prediction based on visual and automatic AI CAC scoring from CSCT scans and LDCT scans as compared to a gold standard, manual CSCT scoring. Methods We retrospectively enrolled 222 patients. Each patient received a 13N-ammonia PET with LDCT and CSCT scan. The time interval between LDCT and CSCT was less than 6 months. Each LDCT and CSCT scan was scored visually, manually, and automatically with AI. For visual scoring we used a previously described 6–points scale (0; 1-10; 11-100; 101-400; 401-100; >1000 Agatston score). For manual scoring we used a generally available software package (Syngo.via,Siemens). The automatic AI scoring was performed with commercially available software based on a deep learning algorithm (included in Syngo.via,Siemens). Each manually and automatically measured Agatston score was converted into the 6-points scale. We performed a per patient analysis; the risk group categorization was based on the total Agatston score. Spearman correlation coefficient was used to analyse the association between manual and automatic AI scoring methods. Agreement between visual, manual, and automatic AI scoring methods was determined using weighted kappa test with 95% confidence intervals (95%CI). Results The correlation between manual scoring from LDCT and CSCT scans was 0.96 (p < 0.001).The agreement between manual scoring from two scans, however, was low with weighted kappa equal 0.57 (95% CI 0.51 – 0.63). 91,9% of calcium scores measured by AI software on CSCT were in the same risk group as manual CSCT scores.The agreement between AI scoring and manual scoring using CSCT was excellent, the weighted kappa was equal 0.95 (95% CI 0.92 - 0.97).Based on visual scoring on LDCT scans, 74,3% of the scores were in the same category as manual scoring on CSCT scans. The agreement between the visual scoring on LDCT scans and a gold standard was strong, weighted kappa equal was 0.82 (95% CI 0.77 – 0.86). The agreement between manual and automatic scoring on LDCT using manual CSCT as the gold standard was low (0.57, 95 % CI 0.51 – 0.63; 0.49, 95 % CI 0.43 – 0.56, respectively). Based on visual LDCT scoring, 7 patients were incorrectly classified as calcium score 0, which underestimated the overall patients’ risk.The AI method scoring CSCT scans, classified 2 patients incorrectly as non-calcium risk group. Conclusions CAC can be automatically assessed from CSCT scans with commercially available AI software.Of manual, automatic, and visual CAC scoring on LDCT scans the visual scoring showed the highest agreement with the gold standard manual CSCT CAC scoring.

Background: Breast cancer and lung cancer are the leading causes of cancer-related mortality in women. Computed tomography (CT) plays an important role in lung cancer examination but an unidentified role in breast examination. Objectives: To investigate the feasibility of breast composition categorization according to the fifth edition of Breast Imaging-Reporting and Data System (BI-RADS) atlas in low-dose CT screening. Patients and Methods: This was a cross-sectional study completed in The 5th Affiliated Hospital of Sun Yat-sen University, Zhuhai, China. We collected the imaging data of 57 women, who underwent low-dose chest CT scan and mammography within one week from 1st October 2013 to 31st March 2015. Two radiologists independently interpreted the mammograms and chest CT scans and classified the breast composition into categories a, b, c, and d. We also summarized the distribution of breast composition categories by collecting, observing, and classifying the chest CT scans from 1916 female examinees from 1st October 2013 to 31st March 2016. Results: Excellent agreement was observed between the two radiologists, using both low-dose CT scan (κ = 0.91) and mammography (κ = 0.86). Agreement between low-dose chest CT scan and mammography was moderate for radiologist A (κ = 0.50) and radiologist B (κ = 0.43). More breasts were classified in categories a and b on the chest CT scan compared to mammography according to both radiologist A (P < 0.01) and radiologist B (P < 0.01). The proportion of non-dense breast tissues (categories a & b) increased with advancing age, while the proportion of dense breast tissues (categories c & d) decreased (P < 0.05). With advancing age, the probability of non-dense breasts increased, while the probability of dense breasts decreased. Conclusions: Based on the findings, it is feasible to categorize breast composition using low-dose chest CT. In the older age group, the probability of non-dense breasts increased.

ISUOG Interim Guidance on 2019 novel coronavirus infection during pregnancy and puerperium: information for healthcare professionals.

Firstly, to validate automatically and visually scored coronary artery calcium (CAC) on low dose CT (LDCT) scans with a dedicated calcium scoring CT (CSCT) scan. Secondly, to assess the added value of CAC scored from LDCT scans acquired during [15O]-water-PET myocardial perfusion imaging (MPI) on prediction of major adverse cardiac events (MACE). 572 consecutive patients with suspected coronary artery disease, who underwent [15O]-water-PET MPI with LDCT and a dedicated CSCT scan were included. In the reference CSCT scans, manual CAC scoring was performed, while LDCT scans were scored visually and automatically using deep learning approach. Subsequently, based on CAC score results from CSCT and LDCT scans, each patient's scan was assigned to one out of five cardiovascular risk groups (0; 1-100; 101-400; 401-1000; >1000) and the agreement in risk group classification between CSCT and LDCT scans was investigated. MACE was defined as a composite of all-cause death, nonfatal myocardial infarction, coronary revascularization, and unstable angina. The agreement in risk group classification between reference CSCT manual scoring and visual/automatic LDCT scoring from LDCT was 0.66 (95% CI: 0.62-0.70) and 0.58 (95% CI: 0.53-0.62), respectively. Based on visual and automatic CAC scoring from LDCT scans, patients with CAC>100 and CAC>400, respectively, were at increased risk of MACE, independently of ischemic information from the [15O]-water-PET scan. There is a moderate agreement in risk classification between visual and automatic CAC scoring from LDCT and reference CSCT scans. Visual and automatic CAC scoring from LDCT scans improve identification of patients at higher risk of MACE.

Radiation Management for Interventions Using Fluoroscopic or Computed Tomographic Guidance during Pregnancy: A Joint Guideline of the Society of Interventional Radiology and the Cardiovascular and Interventional Radiological Society of Europe with Endorsement by the Canadian Interventional Radiology Association

Novel corona virus disease (COVID-19) in pregnancy: What clinical recommendations to follow?

To compare the efficacy of low-dose and standard-dose computed tomography (CT) for the diagnosis of ureteral stones. Unenhanced helical CT was performed with both a standard dose (260 mAs, pitch 1.5) and a low dose (50 mAs, pitch 1.5) in 121 patients suspected of having acute renal colic. The two studies were prospectively and independently interpreted for the presence and location of ureteral stones, abnormalities unrelated to stone disease, identification of secondary signs, i.e. hydronephrosis and perinephric stranding, and tissue rim sign. The standard-dose CT images were interpreted by one reviewer and the low-dose CT images independently by two reviewers unaware of the standard-dose CT findings. The findings of the standard and low-dose CT scans were compared with the exact McNemar test. Interobserver agreements were assessed with kappa analysis. The effective radiation doses resulting from two different protocols were calculated by means of commercially available software to which the Monte-Carlo phantom model was given. The sensitivity, specificity, and accuracy of standard-dose CT for detecting ureteral stones were 99%, 93%, and 98%, respectively, whereas for the two reviewers the sensitivity of low-dose CT was 93% and 95%, specificity 86%, and accuracy 92% and 94%. We found no significant differences between standard-dose and low-dose CT in the sensitivity and specificity for diagnosing ureter stones (P >0.05 for both). However, the sensitivity of low-dose CT for detection of 19 stones less than or equal to 2 mm in diameter was 79% and 68%, respectively, for the two reviewers. Low-dose CT was comparable to standard-dose CT in visualizing hydronephrosis and the tissue rim sign. Perinephric stranding was far less clear on low-dose CT. Low-dose CT had the same diagnostic performance as standard-dose CT in diagnosing alternative diseases. Interobserver agreement between the two low-dose CT reviewers in the diagnosis of ureter stones and alternative diseases, the identification of secondary signs, and tissue rim sign were high, with kappa values ranging from 0.769 to 0.968. On standard-dose CT scans, the calculated mean effective radiation dose was 7.30 mSv for males and 10.00 mSv for females. On low-dose CT scans, the calculated mean effective radiation dose was 1.40 mSv for males and 1.97 mSv for females. Compared with standard scans using 260 mAs, low-dose unenhanced helical CT using a reduced tube current of 50 mAs results in a concomitant decrease in the radiation dose of 81%. Although low-dose CT was limited in its ability to depict small-sized calculi less than or equal to 2 mm, it is still comparable to standard-dose CT for the diagnosis of ureter stones and alternative disease.

Imaging in Diagnosis, Treatment, and Follow-Up of Stone Patients

Background: The extensive studies on the Computed Tomography (CT) and clinical manifestations of coronavirus disease 2019 (COVID-19) patients and the treatment monitoring, attention on pregnant women with COVID-19 pneumonia (PWCP) remains relatively rare. Methods: Our hospital is a designated hospital for the PWCP. We reviewed the clinical data and CT imaging of 15 consecutive PWCP patients in our hospital from January 20 to February 10, 2020. A semi-quantitative scoring system was used to estimate the time course change on chest CT. Symptoms and laboratory results were analyzed, treatment experience summarized, and clinical outcome tracked. Findings: 11 patients had successful delivery (10 cesarean and 1 vaginal) during the study and 4 are still in pregnancy (3 in the second trimester and 1 in the third). No neonatal asphyxia, death, still birth, and abortion reported. Up to February 20, 2020, no severe pneumonia or severe pneumonia and acute respiratory distress syndrome (ARDS) occurred. A total of 25 low-dose chest CT scans were performed in all the 15 patients. The most common early finding on chest CT was ground glass opacity (GGO). With disease progression, crazy paving pattern and consolidations occurred. The abnormalities had shown absorptive changes at the end of the study for all patients. The chest CT imaging progression pattern was similar to that of non-pregnant women. The most common onset symptoms of PWCP were fever (13/15) and cough (9/15). The most common laboratory finding was lymphocytopenia (12/15). In this report, CT images before and after delivery showed no signs of pneumonia aggravation. The 4 cases still in pregnancy were not treated with antiviral drugs, but also achieved good recovery. Interpretation: Pregnancy and childbirth did not aggravate the course of symptoms or CT features of COVID-19 Pneumonia. Pregnant women with COVID-19 pneumonia were mostly mild type, presenting with clinical features and CT imaging progression pattern similar to those of non-pregnant women. No infection was found in the newborns. In this report, the pregnant women achieved a good recovery without use of antiviral drugs. Funding Statement: No funding is provided in this study. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: This study was approved by the Ethics Committee of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. Informed consent for this retrospective study was waived.

To evaluate non-intravenously enhanced low-dose computed tomography with oral contrast (LDCT) for the assessment of pregnant women with right lower quadrant pain, when magnetic resonance imaging (MRI) is not immediately available. One hundred and thirty-eight consecutive pregnant women with acute abdominal pain were admitted in our emergency centre. Thirty-seven (27%) of them, with clinical suspicion of acute appendicitis, underwent abdominal ultrasonography (US). No further examination was recommended when US was positive for appendicitis, negative with low clinical suspicion or showed an alternative diagnosis which explained the clinical presentation. All other patients underwent LDCT (<2.5 mSv). Standard intravenously enhanced CT or MRI was performed when LDCT was indeterminate. Eight (22%) of 37 US exams were reported normal, 25 (67%) indeterminate, 1 (3%) positive for appendicitis, 3 (8%) positive for an alternative diagnosis. LDCT was obtained in 29 (78%) patients. It was reported positive for appendicitis in 9 (31%), for alternative diagnosis in 2 (7%), normal in 13 (45%) and indeterminate in 5 (17%). Further imaging (standard CT or MRI) showed appendicitis in 2 of these 5 patients, was truly negative in 1, indeterminate in 1 and falsely positive in 1. An appendicitis was confirmed at surgery in 12 (32%) of the 37 patients. The sensitivity and the specificity of the algorithm for appendicitis were 100% (12/12) and 92% (23/25), respectively. The proposed algorithm is very sensitive and specific for detection of acute appendicitis in pregnant women; it reduces the need of standard CTs when MRI is not available as second-line imaging. • In pregnant women, US is limited by an important number of indeterminate results • Low-dose CT can be used after an inconclusive US for the diagnosis of appendicitis in pregnant women • An algorithm integrating US and low-dose CT is highly sensitive and specific for appendicitis in pregnant women.

This study aimed to assess the severity and outcomes of COVID-19 in pregnant women, focusing on laboratory and radiological discrepancies between pregnant women and matched nonpregnant women. In this retrospective cross-sectional analysis, we matched 107 nonpregnant women with 66 pregnant women in terms of age, comorbidities, and the interval between symptom onset and hospital admission. Demographic, clinical, laboratory, and radiological data were collected, and chest CT scans were evaluated using a severity scale ranging from 0 to 5. Logistic regression and adjusted Cox regression models were used to assess the impact of various factors on pregnancy status and mortality rates. Differences in several laboratory parameters, including the neutrophil-to-lymphocyte ratio, liver aminotransferases, alkaline phosphatase, urea, triglycerides, cholesterol, HbA1c, ferritin, coagulation profiles, and blood gases, were detected. Radiologic exams revealed that nonpregnant women had sharper opacities, whereas pregnant women presented with hazy opacities and signs of crypt-organizing pneumonia. A notable difference was also observed in the pulmonary artery diameter. The mortality rate among pregnant women was 4.62%, which was comparable to the 5.61% reported in nonpregnant patients. Compared with nonpregnant patients, pregnancy did not significantly affect the severity or mortality of COVID-19. Our study revealed discernible differences in specific laboratory and imaging markers between pregnant and nonpregnant COVID-19 patients.

Object In this study, the authors describe their experience with a low-dose head CT protocol for a preselected neurosurgical population at a dedicated pediatric hospital (Seattle Children's Hospital), the largest number of patients with this protocol reported to date. Methods All low-dose head CT scans between October 2011 and November 2012 were reviewed. Two different low-dose radiation dosages were used, at one-half or one-quarter the dose of a standard head CT scan, based on patient characteristics agreed upon by the neurosurgery and radiology departments. Patient information was also recorded, including diagnosis and indication for CT scan. Results Six hundred twenty-four low-dose head CT procedures were performed within the 12-month study period. Although indications for the CT scans varied, the most common reason was to evaluate the ventricles and catheter placement in hydrocephalic patients with shunts (70%), followed by postoperative craniosynostosis imaging (12%). These scans provided adequate diagnostic imaging, and no patient required a follow-up full-dose CT scan as a result of poor image quality on a low-dose CT scan. Overall physician comfort and satisfaction with interpretation of the images was high. An additional 2150 full-dose head CT scans were performed during the same 12-month time period, making the total number of CT scans 2774. This value compares to 3730 full-dose head CT scans obtained during the year prior to the study when low-dose CT and rapid-sequence MRI was not a reliable option at Seattle Children's Hospital. Thus, over a 1-year period, 22% of the total CT scans were able to be converted to low-dose scans, and full-dose CT scans were able to be reduced by 42%. Conclusions The implementation of a low-dose head CT protocol substantially reduced the amount of ionizing radiation exposure in a preselected population of pediatric neurosurgical patients. Image quality and diagnostic utility were not significantly compromised.

Objective Covid-19 became a pandemic, and researchers have not been able to establish a treatment algorithm. The pregnant population is also another concern for health care professionals. There are physiological changes related to pregnancy that result in different laboratory levels, radiological findings and disease progression. The goal of the present article is to determine whether the laboratory results and radiological findings were different in non-pregnant women (NPWs) of reproductive age and pregnant women (PWs) diagnosed with the Covid-19 infection.Methods Out of 34 patients, 15 (44.11%) PWs and 19 (55.8%) NPWs were included in the study. Age, comorbidities, complaints, vitals, respiratory rates, computed tomography (CT) findings and stages, as well as laboratory parameters, were recorded from the hospital database.Results The mean age of the PWs was of 27.6 ± 0.99 years, and that of the NPWs was of 37.63 ± 2.00; when age was compared between the groups, a statistically significant difference (p = 0.001) was found. The mean systolic blood pressure of the PWs was of 116.53 ± 11.35, and that of the NPWs was of 125.53 ± 13.00, and their difference was statistically significant (p = 0.05). The difference in the minimum respiratory rates of the patients was also statistically significant (p = 0.05). The platelet levels observed among the PWs with Covid-19 were lower than those of the NPWs (185.40 ± 39.09 × 109/mcL and 232.00 ± 71.04 × 109/mcL respectively;p = 0.05). The mean D-dimer value of the PWs was lower in comparison to that of the NPWs (p < 0.05).Conclusion The laboratory findings and imaging studies may differ between pregnant and non-pregnant populations. It is important to properly interpret these studies. Future studies with a higher number of patients are required to confirm these preliminary data.

Objective To explore the clinical application value of one-stop clinic for assessment of risk (OSCAR) for Down syndrome (DS) during frist trimester. Methods From March 2016 to December 2017, a total of 4 219 pregnant women who underwent OSCAR screening during frist trimester were selected into thisi study. The pre-delivery age was 17.3-51.8 years old and the gestational age was 11-13+ 6 weeks. All pregnant women were measured for nuchal translucency (NT) at gestational age of 11-13+ 6 weeks. Time-resolved immunofluorescence analysis was used to detect the serum pregnancy-related protein (PAPP-A) and free β-human chorionic gonadotropin (fβ-hCG) levels of pregnant women. The measured serum PAPP-A and fβ-hCG values were input into the prenatal screening data management software LifeCycle 4.0. The software automatically calculated the multiples of median of serum fβ-hCG and PAPP-A levels (MoM). The risks of DS and 18- trisomy syndrome were calculated in combination with the clinical data of pregnant women′s pre-delivery age, body weight on the day of blood drawing, gestational age indicated by ultrasound examination, number of fetuses, etc. For those with high risk of screening results, further amniocentesis is recommended for karyotype analysis of amniotic fluid cells. The screening result is that low-risk pregnant women will undergo prenatal screening again during second trimester. All high-risk pregnant women were followed up to 42 days after the birth of the fetus. The procedure followed in this study conforms to the ethical standards formulated by the Medical Ethics Committee of Nanning Second People′s Hospital. All pregnant women have signed an informed consent form before undergoing OSCAR screening or interventional prenatal diagnosis during the first trimester of pregnancy with the approval of the Committee (Approval No. 20190924). Results ① Among the 4 219 pregnant women screened by OSCAR during first trimester, the high risk rate of DS was 2.5% (103/4 219) and the high risk rate of 18-trisomy syndrome was 0.3% (11/4 219). The difference of DS and 18-trisomy syndrome in different pre-delivery age groups was statistically significant, respectively (P<0.05). Further comparison of DS high-risk rate shows that the DS high risk rate of pregnant women ≥35 years old was higher than that of other four different age ranges, and the differences were also statistically significant (P<0.05). ② NT value increased gradually with the increase of gestational age, and MoM of NT value also increased with the increase of gestational age. ③ The median serum PAPP-A level of pregnant women increased with the increase of pregnancy age, while the median serum fβ-hCG level decreased with the increase of pregnancy age. ④ Among the 4 219 pregnant women who underwent OSCAR in early pregnancy, 113 (2.7%) were at high risk and 4 106 (97.3%) were at low risk. Among 113 high-risk pregnant women, 42 (37.2%, 42/113) agreed to undergo amniocentesis or chorionic villus biopsy, and 3 were diagnosed as abnormal by karyotype analysis of amniotic fluid cells, of which 2 cases (34 and 33 years old, respectively) were DS and 1 case (22 years old) was 13-trisomy syndrome. ⑤ In 113 cases of screening high-risk pregnant women, 1 case of pregnant women had stopped growth and development before prenatal diagnosis, and then induced labor. Further follow-up screening of low-risk pregnant women found that 2 pregnant women had stillbirth and induced labor. The PAPP-A MoM values of the 2 pregnant women were abnormal during prenatal screening, which were 0.35 and 0.28, respectively (normal reference range was 0.5-2.5). ⑥ Follow-up results of 113 pregnant women screened for high-risk showed that 106 cases (93.8%) were successfully followed up and 7 cases (6.2%) were missed. Conclusions OSCAR for DS during first trimester is simple, economical and cost-effective. In addition, the abnormal PAPP-A MoM value can be used as a reference index for adverse pregnancy outcomes. Key words: Down syndrome; Prenatal diagnosis; Pregnancy trimester, first; Pregnancy-associated plasma protein-A; Pregnant women