scholarly journals Low-Dose High-Pitch Cardiac CT to Evaluate Abnormal Pacemaker Lead Position

2021 ◽  
Vol 11 (09) ◽  
pp. 434-438
Author(s):  
Baosheng Li ◽  
Chongfu Jia
2014 ◽  
Vol 25 (6) ◽  
pp. 1197-1199 ◽  
Author(s):  
Swati Deshmukh ◽  
W. Reid Thompson ◽  
Stefan L. Zimmerman

AbstractWe describe the use of low-dose dual-source cardiac for the evaluation of a neonate with suspected total anomalous pulmonary venous connection. This novel technique obviates the need for sedation or breathholding. Radiation dose-reduction strategies result in sub-mSv-estimated effective doses, substantially lower than annual background radiation dose. Low-dose, high-pitch cardiac CT should be considered as an alternative to MRI or diagnostic cardiac catheterisation in neonates with complex CHD, requiring definitive anatomic evaluation.


Author(s):  
Julia Schäfer ◽  
Holger Haubenreisser ◽  
Mathias Meyer ◽  
Joachim Grüttner ◽  
Thomas Walter ◽  
...  

Introduction To prospectively evaluate the feasibility of single contrast bolus high-pitch CT pulmonary angiography (CTPA) subsequently followed by low-dose retrospectively ECG-gated cardiac CT (4D-cCT) in patients with suspected pulmonary embolism (PE) to accurately evaluate right ventricular (RV) function. Materials and Methods 62 patients (33 female, age 65.1 ± 17.5 years) underwent high-pitch CTPA examination with 80cc of iodinated contrast material. 5 s after the end of the high-pitch CTPA study, a low-dose retrospectively ECG-gated cardiac CT examination was automatically started. The volume CT dose index (CTDI vol) and dose length product (DLP) were recorded in all patients and the effective dose was calculated. For the assessment of image quality, attenuation was measured as Hounsfield units (HUs) within various regions of interest (ROIs). These ROIs were used to calculate the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Subjective image quality was assessed using a five-point Likert scale. On 4D-cCT, the ejection fraction of both ventricles (RVEF, LVEF) as well as the ratio of RVEF and LVEF (RVEF/LVEF) was assessed. The statistical difference of all parameters between the PE and non-PE group was calculated. Results The mean effective radiation dose was 4.22 ± 2.05 mSv. Attenuation measurements on CTPA showed the highest attenuation values in the main pulmonary artery (442.01 ± 187.64). On 4D-cCT attenuation values were highest in the descending aorta (560.59 ± 208.81). The CNR and SNR values on CTPA were highest within the main pulmonary artery (CNR = 12.43 ± 4.57; SNR = 15.14 ± 4.90). On 4D-cCT images, the highest SNR and CNR could be measured in the descending aorta (CNR = 10.26 ± 5.57; SNR = 10.86 ± 5.17). The mean LVEF was 60.73 %± 14.65 %, and the mean RVEF was 44.90 %± 9.54 %. The mean RVEF/LVEF was 0.79 ± 0.29. There was no significant difference between the PE and non-PE group for either of the parameters. Conclusion The investigated combined CTPA and 4D-cCT protocol is feasible using a single contrast bolus and allows the evaluation of RV function in patients with suspected PE. Further studies have to evaluate the additional value of this protocol regarding risk stratification in patients with PE. Key Points:  Citation Format


2019 ◽  
Vol 4 (4) ◽  
pp. 607-614
Author(s):  
Jean Abitbol

The purpose of this article is to update the management of the treatment of the female voice at perimenopause and menopause. Voice and hormones—these are 2 words that clash, meet, and harmonize. If we are to solve this inquiry, we shall inevitably have to understand the hormones, their impact, and the scars of time. The endocrine effects on laryngeal structures are numerous: The actions of estrogens and progesterone produce modification of glandular secretions. Low dose of androgens are secreted principally by the adrenal cortex, but they are also secreted by the ovaries. Their effect may increase the low pitch and decease the high pitch of the voice at menopause due to important diminution of estrogens and the privation of progesterone. The menopausal voice syndrome presents clinical signs, which we will describe. I consider menopausal patients to fit into 2 broad types: the “Modigliani” types, rather thin and slender with little adipose tissue, and the “Rubens” types, with a rounded figure with more fat cells. Androgen derivatives are transformed to estrogens in fat cells. Hormonal replacement therapy should be carefully considered in the context of premenopausal symptom severity as alternative medicine. Hippocrates: “Your diet is your first medicine.”


Author(s):  
I Tsiflikas ◽  
M Teufel ◽  
C Thomas ◽  
S Fleischer ◽  
CD Claussen ◽  
...  
Keyword(s):  
Low Dose ◽  

2021 ◽  
pp. 102209
Author(s):  
Jawook Gu ◽  
Tae Seong Yang ◽  
Jong Chul Ye ◽  
Dong Hyun Yang
Keyword(s):  
Low Dose ◽  

PLoS ONE ◽  
2014 ◽  
Vol 9 (3) ◽  
pp. e90268 ◽  
Author(s):  
Zhiwei Wang ◽  
Yu Chen ◽  
Yining Wang ◽  
Huadan Xue ◽  
Zhengyu Jin ◽  
...  

Author(s):  
Michael Esser ◽  
Sabine Hess ◽  
Matthias Teufel ◽  
Mareen Kraus ◽  
Sven Schneeweiß ◽  
...  

Purpose To analyze possible influencing factors on radiation exposure in pediatric chest CT using different approaches for radiation dose optimization and to determine major indicators for dose development. Materials and Methods In this retrospective study at a clinic with maximum care facilities including pediatric radiology, 1695 chest CT examinations in 768 patients (median age: 10 years; range: 2 days to 17.9 years) were analyzed. Volume CT dose indices, effective dose, size-specific dose estimate, automatic dose modulation (AEC), and high-pitch protocols (pitch ≥ 3.0) were evaluated by univariate analysis. The image quality of low-dose examinations was compared to higher dose protocols by non-inferiority testing. Results Median dose-specific values annually decreased by an average of 12 %. High-pitch mode (n = 414) resulted in lower dose parameters (p < 0.001). In unenhanced CT, AEC delivered higher dose values compared to scans with fixed parameters (p < 0.001). In contrast-enhanced CT, the use of AEC yielded a significantly lower radiation dose only in patients older than 16 years (p = 0.04). In the age group 6 to 15 years, the values were higher (p < 0.001). The diagnostic image quality of low-dose scans was non-inferior to high-dose scans (2.18 vs. 2.14). Conclusion Radiation dose of chest CT was reduced without loss of image quality in the last decade. High-pitch scanning was an independent factor in this context. Dose reduction by AEC was limited and only relevant for patients over 16 years. Key Points Citation Format


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