Objective:To explore the application value of artificial intelligence (AI) in image post-processing of reconstructed CTA based on CT cerebral perfusion (CTP).Methods:Clinical and radiological data of 100 patients suspected of cerebrovascular diseases in Hebei General Hospital from January to July 2020 were retrospectively selected. All patients were divided into A and B group on average according to the different examination schemes. Cerebral CTP examination was performed in group A (the temporal maximum intensity projective data set generated by the first 5 time phases in the maximum period of the difference between arteriovenous CT values selected as subgroup A1, and the corresponding original thin-layer images selected as subgroup A2), single phase CTA examination was performed in group B, manual and AI image post-processing were performed respectively. Subjective scoring of the image data was performed, and the objective bid evaluation indexes such as CT value, noise (SD), signal-to-noise ratio (SNR), contrast to noise ratio (CNR) were measured, the qualified rate of artificial and AI vascular segmentation was counted, and post-processing time were recorded. The objective evaluation indexes were compared between three groups using one-way ANOVA, and the Kruskal-Wallis H test was used to compare the difference of subjective scores.Results:Statistically significant differences were observed in subjective score and objective evaluation index of original images among group A1, group A2 and group B (all P<0.05). Among them, arterial enhancement, arteriolar detail display score, cerebral artery CT value, SNR and CNR in group A1 were higher than those in group A2 and group B (all P<0.05). In a total of 100 patients with 1 100 blood vessels, the qualified rates of AI vascular segmentation in group A1 [98.4% (541/550)] and group B [98.7% (543/550)] were higher than those of manual [82.9% (456/550), 87.1% (479/550), χ2=77.392, 56.521, P<0.001], but the qualified rate of AI vascular segmentation of group A2 [78.4% (431/550)] was lower than that of manual [85.6% (471/550), χ2=9.855, P=0.002]. The completion time of AI post-processing were reduced by 56.30%, 49.63%, 50.81%, respectively than those with manual. Conclusion:Compared with manual image post-processing, AI has certain advantages in image quality and work efficiency of reconstructed CTA post-processing based on CTP de-noising dataset, and it is worth popularizing and applying in the image post-processing of cerebrovascular disease, combined with artificial quality control.

Objective: To investigate the feasibility of one-step coronary and carotid-cerebrovascular computed tomography angiography (CTA) using high-pitch Double Turbo Flash mode and to analyze the image quality and radiation dose in patients with heart rate variability using multi-slice detector dual-source CT. Methods: A total of 79 patients with heart rate variability higher than 3 beat/min (bpm) were retrospectively analyzed. They were grouped by the scanning methods. Group A (n=40) were performed double turbo flash mode for one-step coronary and carotid-cerebrovascular arteriesinjected with one injection of contrast agent.further divided into Single A (only the phase 1 image)and Double A(combined images of phases 1 and 2). Group B (n=39) were performed separately with twice injection of contrast agent. Subjective scoring was performed on the image quality of the group Single A, Double A and B using a 4-point. Then the objective parameters of image quality, CT attenuations, image noise, signal-to-noise (SNR), and contrast-to-noise (CNR), were evaluated. Then subjective scores, objective evaluation indicators, and radiation dose were compared with one-way ANOVA analysis among the three groups.Contrast agent were compared by using t test in group A and B. Results: No significant difference was found (F=2.093, P=0.128) for the subjective scores of the head and neck CTA among the three groups with (3.47±0.51), (3.53±0.51), (3.69±0.47). Significant difference was found (F=50.955, P<0.01) for the subjective scores of coronary CTA among the three groups with (2.70±0.76), (3.35±0.66), (3.58±0.50), and there was no statistically significant difference between Double A and B groups (P=0.104), met the requirements for diagnosis. The objective evaluation of the three groups compared the head and neck CTA images were statistically significant (P<0.05), of which the difference between the Single A and the Double A was not statistically significant (P>0.05), met the requirements for diagnosis; the differences in SNR and CNR of coronary CTA images are statistically significant (F=12.991, 12.236, P<0.01), and there was no statistically significant difference between Double A and B (P>0.05), met the requirements for diagnosis. Radiation dose in the group Double A was lower than group B (decreased by 46.15%,P<0.01).The amount of the contrast agent in the group Double A was lower than group B (decreased by 44.13%, t=-45.455;P<0.01). Conclusion The double turbo flash mode is feasibility for one-step coronary and carotid-cerebrovascular CTA in patients with the heart rate variability using multi-slice dual-source CT.This scan mode can maintain the diagnostic image quality with low contrast agent and radiation dose.

Objective : To evaluate the morphology of the upper airway of children with obstructive sleep apnea-hypopnea syndrome (OSAHS) using cone-beam computed tomography (CBCT) combined with polysomnography (PSG) and provide references for clinical practice. Methods: CBCT data of 45 OSAHS children and 45 normal children and PSG data of the OSAHS group were retrospectively collected. Three-dimensional reconstructions were performed using NNT 9.0 software. The total upper airway volume, nasopharyngeal volume, palatopharyngeal volume, glossopharyngeal volume, laryngopharyngeal volume, minimum cross-sectional area, anterior-posterior diameter of the minimum cross-section, and lateral diameter of the minimum cross-section were measured and recorded. According to PSG monitoring results, patients with an obstructive apnea hypopnea index (OAHI) and lowest oxygen saturation (LSaO2) were assessed. Body mass index (BMI) was recorded. The correlation between airway volume parameters, BMI and PSG test results was analyzed. Results: The total upper airway volume, nasopharyngeal volume, palatopharyngeal volume, glossopharyngeal volume, laryngopharyngeal volume, minimum cross-sectional area, anterior-posterior diameter of the minimum cross-section, and lateral diameter of the minimum cross-section of the OSAHS group were significantly reduced compared with those of the control group (P<0.05). In the OSAHS group, the total upper airway volume, the minimum cross-sectional area and the lateral diameter of the minimum cross-section showed moderate negative correlations with the obstructive apnea hypopnea index (OAHI) (P<0.05). Moreover, the total upper airway volume, minimum cross-sectional area, anterior-posterior diameter of the minimum cross-section and lateral diameter of the minimum cross-section showed no correlation with the minimum blood oxygen saturation (P>0.05). No significant correlation was noted between BMI and PSG in the OSAHS group (P>0.05). Conclusion The morphology of the upper airway of children with OSAHS was significantly smaller than that of normal children. CBCT three-dimensional technology for analyzing the upper airway has a certain value in evaluating the morphology and degree of obstruction of the upper airway in children with OSAHS.