scholarly journals Use of Multi-Modality Technology to Reduce the Radiation Dose of Multi-Slice Spiral CT Coronary Angiography (MSCTCA) in Normal Weight and Overweight Patients

Author(s):  
Xiao lu Hu ◽  
Pei kai Huang ◽  
Meng Zhang ◽  
Min Lei ◽  
Jun Chen ◽  
...  

Abstract Purpose: This study was performed to explore the value of multi-modality technology, with a combination of narrow acquisition window, isocentric scanning, low tube voltage, low tube current and iterative reconstruction (IR), for reducing the radiation dose in multi-slice spiral computed tomography coronary angiography (MSCTCA). Materials and methods: In this prospective randomised controlled study, 154 patients with coronary heart disease (CHD) were classified according to body mass index (BMI) as normal weight (BMI 18–27kg/m2) or overweight (BMI ≥ 27 kg/m2), and divided into four groups: multi-modality–normal BMI group (A1, n = 82); multi-modality–overweight group (B1, n = 17); conventional–normal BMI group (A2, n = 39); and conventional–overweight group (B2, n = 16). The parameters in the multi-modality groups were as follows: isocentric scan, tube voltage = 80 kV, tube current control using 80% “smart milliampere”, and maximum current during 60–80% of the RR interval. The parameters in the conventional groups were as follows: normal position, tube voltage = 100 kV, tube current control using smart milliampere, and maximum current during 30–80% of the RR interval. The effective radiation dose (ED), objective image quality (IQ), noise, signal-to-noise ratio (SNR), contrast signal-to-noise ratio (CNR) and subjective 5-point Likert scale IQ scores of MSCTCA images were compared among the four groups. Results: The average EDs of groups A1, A2, B1and B2 were( 1.13±0.35 ) mSv, ( 3.36±1.30 ) mSv, ( 1.54±0.53 ) mSv and ( 5.90±0.93 ) mSv, respectively. There were statistically significant differences in ED between groups A1 and A2, and between groups B1 and B2 (all P < 0.01). Noise was significantly lower, and both SNR and CNR were significantly higher, in group A2 than group A1 (all P < 0.01), but there were no significant differences in these parameters between groups B1 and B2 (P = 0.14–0.51). The average IQ scores of groups A1, A2, B1and B2 were 4.46±0.59(Fig.3), 4.45±0.62(Fig.4), 4.39±0.68(Fig.5) and 4.42±0.66(Fig.6),respectively. There were no significant differences in subjective IQ scores among the four groups (P = 0.12). Consistency among observers in the subjective IQ scores of the four groups was very good, with intraclass correlation coefficients (ICCs) of 0.71–0.90. The subjective IQ scores of the coronary artery were excellent in all four groups, with a total good-to-excellent rate of ≥ 92.64%, and the total number of evaluable segments in the images of all four groups was ≥ 98.26%. Conclusions: Under conditions appropriate for clinical diagnosis, multi-modality technology can reduce the radiation dose of MSCTCA scans in both normal weight and overweight patients.

Obesity Facts ◽  
2021 ◽  
pp. 1-9
Author(s):  
Serdar Sahin ◽  
Havva Sezer ◽  
Ebru Cicek ◽  
Yeliz Yagız Ozogul ◽  
Murat Yildirim ◽  
...  

<b><i>Introduction:</i></b> The aim of this was to describe the predictors of mortality related to COVID-19 infection and to evaluate the association between overweight, obesity, and clinical outcomes of COVID-19. <b><i>Methods:</i></b> We included the patients &#x3e;18 years of age, with at least one positive SARS-CoV-2 reverse transcriptase-polymerase chain reaction. Patients were grouped according to body mass index values as normal weight &#x3c;25 kg/m<sup>2</sup> (Group A), overweight from 25 to &#x3c;30 kg/m<sup>2</sup> (Group B), Class I obesity 30 to &#x3c;35 kg/m<sup>2</sup> (Group C), and ≥35 kg/m<sup>2</sup> (Group D). Mortality, clinical outcomes, laboratory parameters, and comorbidities were compared among 4 groups. <b><i>Results:</i></b> There was no significant difference among study groups in terms of mortality. Noninvasive mechanical ventilation requirement was higher in group B and D than group A, while it was higher in Group D than Group C (Group B vs. Group A [<i>p</i> = 0.017], Group D vs. Group A [<i>p</i> = 0.001], and Group D vs. Group C [<i>p</i> = 0.016]). Lung involvement was less common in Group A, and presence of hypoxia was more common in Group D (Group B vs. Group A [<i>p</i> = 0.025], Group D vs. Group A [<i>p</i> &#x3c; 0.001], Group D vs. Group B [<i>p</i> = 0.006], and Group D vs. Group C [<i>p</i> = 0.014]). The hospitalization rate was lower in Group A than in the other groups; in addition, patients in Group D have the highest rate of hospitalization (Group B vs. Group A [<i>p</i> &#x3c; 0.001], Group C vs. Group A [<i>p</i> &#x3c; 0.001], Group D vs. Group A [<i>p</i> &#x3c; 0.001], Group D vs. Group B [<i>p</i> &#x3c; 0.001], and Group D vs. Group C [<i>p</i> = 0.010]). <b><i>Conclusion:</i></b> COVID-19 patients with overweight and obesity presented with more severe clinical findings. Health-care providers should take into account that people living with overweight and obesity are at higher risk for COVID-19 and its complications.


Author(s):  
Atul Kapoor ◽  
Goldaa Mahajan ◽  
Aprajita Kapoor

Abstract Objective The aim of this study was to evaluate the use of low peak kilovoltage (kVp) low-volume iodinated contrast protocol for performing coronary computed tomography (CT) angiography (CCTA) in patients using retrospective electrocardiogram (ECG) gating. Materials and Methods Hundred prospective patients undergoing CCTA were studied in two groups, A and B, using 70 kilovoltage (kV) and 120 kV protocols with half and standard intravenous volumes of injected iodinated contrast, respectively. All patients had heart rates less than 100 beats/min and body mass index (BMI) less than 31 kg/m2. Both the groups were evaluated for signal-to-noise (S/N) and contrast-to-noise (C/N) ratios along with radiation dose delivered in millisievert (mSv), and for image quality (IQ), on per patient and per segment basis. Results Patients with group A showed statistically reduced radiation dose of 1.86 mSv compared with 6.86 mSv in group B patients. Marked reduction in image noise with statistically improved S/N and C/N ratios in all coronary vessels was seen in group A. S/N ratios in group A were 20.25, 18.68, 19.04, 17.41, and 18.69 for aorta, left main, left anterior descending, right coronary, and left circumflex arteries while they were 13.34, 11.12, 10.96, 9.74, and 8.67 in group B patients. C/N ratios were also higher in all vessels in group A patients, that is, 19.48, 19.48, 19.04, 19.48, and 17.68, compared with group B patients, who had 12.43, 10.03, 9.23, 9.57, and 8.23 ratios (p < 0.0001). No significant difference in IQ per patient and per vessel was seen between both the groups. Discussion Retrospective ECG-gated low-kVp low-volume iodinated contrast protocol provides good diagnostic quality angiograms in patients with BMI up to 31 kg/m2 and with heart rates of less than 100 beats/min with three times reduced radiation dose. The reduced volume of contrast reduces the cost as well as the chance of contrast-induced nephropathy.


2020 ◽  
pp. 1-6
Author(s):  
Esam Desoky ◽  
Khaled M. Abd Elwahab ◽  
Islam M. El-Babouly ◽  
Mohammed M. Seleem

<b><i>Objective:</i></b> To evaluate the impact of body mass index (BMI) on the outcomes of percutaneous nephrolithotomy (PCNL) in the flank-free modified supine position. <b><i>Patients and Methods:</i></b> A prospective study was carried out in the urology department during the period from May 2015 to October 2019 on 464 patients admitted for PCNL. The patients were divided into 4 matched groups according to their BMI: group A, normal weight with 18.5 ≤ BMI &#x3c;25 kg/m<sup>2</sup>; group B, overweight with 25 ≤ BMI &#x3c;30 kg/m<sup>2</sup>; group C, obese with 30 ≤ BMI &#x3c;40 kg/m<sup>2</sup>; and group D, morbid obesity with BMI ≥40 kg/m<sup>2</sup>. All operative data as well as postoperative outcomes are recorded and compared to each other. <b><i>Results:</i></b> The 4 studied groups were matched regarding age. The comorbidities were slightly higher in groups C and D. The operative time and fluoroscopy time were slightly high in obese and morbid obese groups but with no significant difference. The rate of complications either major or minor was comparable in all groups. No significant difference was seen among all groups regarding hemoglobin loss, stone-free rate, hospital stay, and need for auxiliary procedures. <b><i>Conclusions:</i></b> The outcome of PCNL in flank-free modified supine position is not affected by changes in BMI. The procedure can be performed in obese and morbid obese patients safely with results similar to and comparable to nonobese patients.


2020 ◽  
pp. 028418512091762
Author(s):  
Ting Liang ◽  
Yonghao Du ◽  
Chenguang Guo ◽  
Yuan Wang ◽  
Jin Shang ◽  
...  

Background Computed tomography (CT)-guided percutaneous lung biopsy is usually performed by helical scanning. However, there are no studies on radiation dose, diagnostic accuracy, image quality, and complications based on axial scan mode. Purpose To determine radiation dose, accuracy, image quality, and complication rate following an ultra-low-dose (ULD) protocol for CT-guided lung biopsy in clinic. Material and Methods A total of 105 patients were enrolled to receive CT-guided lung biopsy. The use of an ULD protocol (axial scan) for CT-guided biopsy was initiated. Patients were randomly assigned to axial mode (Group A) and conventional helical mode (Group B) CT groups. 64-slice CT was performed for CT-guided pulmonary biopsy with an 18-G coaxial cutting biopsy needle. The radiation dose, accuracy, image quality, and complication rate were measured. Results Ninety-seven patients were selected for the final phase of the study. There was no significant difference between the two groups for pulmonary nodule characteristics ( P > 0.05). The mean effective dose in group A (0.077 ± 0.010 mSv) was significantly reduced relative to group B (0.653 ± 0.177 mSv, P < 0.001). There was no significant difference in accuracy, image quality, and complication rate ( P > 0.050) between the two modes. Conclusion An ULD protocol for CT-guided lung nodule biopsy yields a reduction in the radiation dose without significant change in the accuracy, image quality, and complication rate relative to the conventional helical mode scan.


2019 ◽  
Vol 03 (01) ◽  
pp. 007-011
Author(s):  
Anurag Chahal ◽  
Sundeep Malla ◽  
Chinmaya Dash ◽  
Deepak Gupta ◽  
Shivanand Gamanagatti

Abstract Purpose To describe a new technique for “pull type” radiologically inserted gastrostomy (RIG) and prospectively compare it with conventional (described) technique in terms of technical ease (fluoroscopy time, radiation dose) and safety profile. Materials and Methods Adult patients with head injury with Glasgow coma scale (GCS) (M score) < 5, one week after decompression or those requiring nutritional support for > 4 weeks, or patients with recurrent aspiration pneumonitis on nasogastric feeding were included. Hemodynamically unstable patients or those with uncorrectable coagulopathy were excluded. Patients underwent pull-type RIG with alternate patient getting allocated to groups A (conventional technique) and B (new technique). The authors compared the technical success, complication rate, fluoroscopy time, radiation dose, and cost of hardware in these two groups. Results The average fluoroscopy time for group A (9 patients) was 498.7 ± 145.3 seconds, whereas for group B (16 patients), it was 302.8 ± 54.1 seconds with p-value = 0.06. The mean radiation dose of group A was 74.7 ± 15.7 mGy, whereas for group B, it was 56.7 ± 14.1 mGy (p-value = 0.004). The minor complication rates were 11.1% in both the groups. Conclusion The authors’ innovative technique using a customized snare has the potential to increase the technical ease of pull-type RIG with reduced fluoroscopy time, radiation dose, and cost with a similar safety profile.


2015 ◽  
Vol 48 (5) ◽  
pp. 292-297 ◽  
Author(s):  
Ricardo Francisco Tavares Romano ◽  
Priscila Silveira Salvadori ◽  
Lucas Rios Torres ◽  
Elisa Almeida Sathler Bretas ◽  
Daniel Bekhor ◽  
...  

AbstractObjective:To assess the reduction of estimated radiation dose in abdominal computed tomography following the implementation of new scan protocols on the basis of clinical suspicion and of adjusted images acquisition parameters.Materials and Methods:Retrospective and prospective review of reports on radiation dose from abdominal CT scans performed three months before (group A – 551 studies) and three months after (group B – 788 studies) implementation of new scan protocols proposed as a function of clinical indications. Also, the images acquisition parameters were adjusted to reduce the radiation dose at each scan phase. The groups were compared for mean number of acquisition phases, mean CTDIvol per phase, mean DLP per phase, and mean DLP per scan.Results:A significant reduction was observed for group B as regards all the analyzed aspects, as follows: 33.9%, 25.0%, 27.0% and 52.5%, respectively for number of acquisition phases, CTDIvol per phase, DLP per phase and DLP per scan (p < 0.001).Conclusion:The rational use of abdominal computed tomography scan phases based on the clinical suspicion in conjunction with the adjusted images acquisition parameters allows for a 50% reduction in the radiation dose from abdominal computed tomography scans.


2018 ◽  
Vol 31 (Supplement_1) ◽  
pp. 29-29
Author(s):  
Styliani Mantziari ◽  
Pierre Allemann ◽  
Michael Winiker ◽  
Marguerite Messier ◽  
Nicolas Demartines ◽  
...  

Abstract Background Current guidelines recommend the use of neoadjuvant chemo-radiation (NCR) for the treatment of locally advanced esophageal cancer, both types, adenocarcinoma (AC) and squamous cell carcinoma (SCC). So far, the optimal dose of radiotherapy to achieve a maximal tumor response within an acceptable toxicity is not yet determined. The aim of this study was to assess the impact of preoperative radiation dose on postoperative outcomes and long-term survival. Methods Consecutive patients operated in two European tertiary centers for AC or SCC, treated with NCR and surgery from 2000–2016 were assessed. Specific postoperative complications (i.e. anastomotic leakage, atrial fibrillation), histological tumor regression grade (TRG, Mandard score), overall and disease-free survival were compared among three patients groups: group A (41.4Gy), group B (45Gy), and group C (50.4Gy). The x2 or Fisher test were used for categorical variables and ANOVA for continuous variables. Survival analysis was done with the Kaplan-Meier method and log-rank test. Results There were 294 patients included; 41.5% (n = 122) had AC and 58.5% (n = 172) SCC. Overall, 9.2%/27 patients received 41Gy, 57.8%/170 patients 45Gy and 33%/97 patients received 50.4Gy. Carboplatin-Paclitaxel was the most frequently used chemotherapy for group A (62.9%), and 5FU-Cisplatin for groups B (69.4%) and C (51.5%). Postoperative anastomotic leakage was lower for group B (7.1%) compared to group A (22.2%) and C (13.4%) (P = 0.036), as was the occurrence of atrial fibrillation (11.8% group B, 33.3% group A and 19.6% group C, P = 0.013). Complete or excellent response (TRG 1–2) was significantly better for group B (58.2%), followed by group C (49.5%) and A (25.9%) patients (P = 0.012). Median overall survival was 48, 27 and 29 months for group A, B and C (P = 0.498), and median disease-free survival was 13, 27 and 18 months (P = 0.411), respectively. Conclusion Preoperative radiotherapy dose of 45Gy with 5FU-Cisplatin was associated with a better histological response and less postoperative adverse outcomes compared to 41Gy and 50.4Gy, with no significant differences in long-term recurrence and survival. The role of the type of chemotherapy and histological tumor type are important co-factors affecting outcome and must be further assessed. Disclosure All authors have declared no conflicts of interest.


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