Objective To retrospectively summarize the normal reference range of trachea wall thickness,lumen diameter,wall area and wall area ratio[WA%=mean wall area/(mean wall area+lumen area)]of Chinese healthy adults,and its related factors. Also,to observe the difference of inner diameter between superior and inferior bronchus.Methods Based on computer measurement techniques of bronchus,a CT quantitative analysis was carried out in 701 cases of normal healthy people who had negative results in lung cancer screening of health examination at our hospital.Results The value of trachea wall thickness,lumen diameter,wall area and wall area ratio was(1.322 mm,18.024 mm,78.93 mm2 ,0.27)respectively.In different gender,the trachea wall thickness,lumen diameter,wall area and wall area ratio had statistical significance (P<0.05).Also,they had good consistency with gender (r=-0.512,-0.472,-0.559,0.315).In different gender and age,the difference of inner diameter between the superior bronchus and inferior bronchus was always a positive value.Conclusion The CT quantitative analysis method has advantages of convenience,direct-vie-wing and accuracy.It is good for quantitative detection and research of bronchus structure.Bronchial wall thickness,lumen diameter, wall area and wall area ratio have significant difference because of gender.The inner diameter of superior bronchus is always greater than that of the inferior bronchus.

Objective:To compare the efficacy and safety of domestic 16-row and imported 8-row mobile CT in clinics.Methods:A total of 1469 patients accepted domestic 16-row mobile CT head scans (1604 times) from March 2017 to August 2018 in Bayi Brain Hospital Affiliated to 7 th Medical Center of General Hospital of People's Liberation Army and Langfang Aidebao Hospital; and 15510 patients accepted imported 8-row mobile CT head scans (24994 times) from January 2016 to August 2018 in Bayi Brain Hospital Affiliated to 7 th Medical Center of General Hospital of People's Liberation Army. All patients underwent horizontal plain and enhanced head scans, cerebral CT angiography (CTA), and helical 3D imaging; and the imaging quality, operating power consumption, computed tomography dose index volume (CTDIvol) and stability within scanning volume ranges under different scanning modes of the two CT scans were compared. Results:(1) Imaging quality: the horizontal scanning of domestic 16-row mobile CT could clearly display low-density tissues such as the eyeball, optic nerve, brain stem, sulcus and cerebral gyrus; the imaging quality of both CT scans in patients with traumatic subdural hematoma and ischemic stroke completely met the clinical diagnosis and treatment standards. (2) Operating power consumption: the per-hour operating power consumption of domestic 16-row mobile CT ([0.286±0.018] kW·h) was obviously lower than that of imported 8-row mobile CT ([0.485±0.028] kW·h). (3) Radiological hazard: the CTDIvol of the horizontal scanning volume range in domestic 16-row mobile CT ([36.270±0.281] mGy) was significantly lower than that in the imported 8-row mobile CT ([82.520±0.441] mGy, P<0.05); the CTDIvol of enhanced axis scan volume range in the domestic 16-row mobile CT ([36.270±0.335] mGy) was significantly lower than that in the imported 8-row mobile CT ([70.728±0.424] mGy, P<0.05); the CTDIvol in the volume of CTA imaging of domestic 16-row mobile CT ([20.600±0.087] mGy) was significantly lower than that in the imported 8-row mobile CT ([29.300±0.335] mGy, P<0.05). The domestic 16-row mobile CT was designed with shock absorbers and guides; domestic 16-row mobile CT had small load, a low center of gravity, and good stability as compared with imported 8-row mobile CT. Conclusion:In terms of head scanning applications, the imaging quality of domestic 16-row mobile CT and imported 8-row mobile CT is in full compliance with clinical diagnostic standards, but the energy consumption and radiation risk of domestic 16-row mobile CT is significantly lower than imported 8-row mobile CT, enjoying good stability as compared with imported 8-row mobile CT.