Clinical and Radiological Features Between Patients with Stable COPD from Plateau and Flatlands: A Comparative Study.

Background: COPD patients living in Tibet are exposed to specific environments and different risk factors and probably have different characteristics of COPD from those living in flatlands. We aimed to describe the distinction between stable COPD patients permanently residing at the Tibet plateau and those in flatlands. Methods: We conducted an observational cross-sectional study that enrolled stable COPD patients from Tibet Autonomous Region People's Hospital (Plateau Group) and Peking University Third Hospital (Flatland Group), respectively. Their demographic information, clinical features, spirometry test, blood routine and high-resolution chest CT were collected and evaluated. Results: A total of 182 stable COPD patients (82 from plateau and 100 from flatland) were consecutively enrolled. Compared to those in flatlands, patients in plateau had a higher proportion of females, more biomass fuel use and less tobacco exposure. CAT score and frequency of exacerbation in the past year were higher in plateau patients. The blood eosinophil count was lower in plateau patients, with fewer patients having an eosinophil count ≥300/µL. On CT examination, the proportions of previous pulmonary tuberculosis and bronchiectasis were higher in plateau patients, but emphysema was less common and milder. The ratio of diameters of pulmonary artery to aorta ≥1 was more often in plateau patients. Conclusion: Patients with COPD living at Tibet Plateau had a heavier respiratory burden, lower blood eosinophil count, less emphysema but more bronchiectasis and pulmonary hypertension. Biomass exposure and previous tuberculosis were more common in these patients.

Clinical and Radiological Features of COPD Patients Living at ≥3000 m Above Sea Level in the Tibet Plateau.

Background: COPD at high altitude may have different risk factors and unique clinical and radiological phenotypes. We aimed to investigate the demographic data, clinical and radiological features of COPD patients permanently residing at the Tibet Plateau (≥3000 meters above sea level). Methods: We conducted an observational cross-sectional study which consecutively enrolled COPD patients visiting the outpatient of Respiratory Medicine at Tibet Autonomous Region People's Hospital from January 2018 to March 2021. All patients were Tibetan permanent residents aging ≥40 years and met the diagnosis of COPD according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. Data including demographic characteristics, altitude of residence, risk factors, respiratory symptoms, comorbidities and medications, as well as computed tomography (CT) measurements were collected. Results: Eighty-four patients with definite COPD were enrolled for analysis. Their mean age was 64.7 (±9.1) years. All patients lived at ≥3000 m above sea level and 34.5% of them lived at ≥4000 m. About 8.3% of the patients were current smokers and 44.0% were ex-smokers. Up to 88.1% of the patients reported long-term exposure to indoor biomass fuels. Most of the patients were classified as having mild-to-moderate (GOLD I: 27.4%; GOLD II: 51.2%) COPD, while 89.3% had a CAT score ≥10. Only 36.9% of the patients received regular long-term medications for COPD in the past year, in whom ICS/LABA and oral theophylline were the most common used pharmacological therapy. On CT scanning, the majority of our patients (70.7%) showed no or minimal emphysema, while signs of previous tuberculosis were found in 45.1% of the patients. Conclusion: COPD patients living at the Tibet Plateau had a heavy respiratory symptom burden, but most of them did not receive adequate pharmacological treatment. Indoor biomass fuel exposure and previous tuberculosis were prevalent, while the emphysema phenotype was less common in this population.

[Endometrial Injury and Preservation after Magnetic Resonance-guided Focused Ultrasound Ablation of Uterine Fibroids].

Objective To explore the risk factors for incident endometrial injury and 3-month endometrial injury after magnetic resonance-guided focused ultrasound(MRgFUS)ablation of uterine fibroids(UF). Methods UF patients who were diagnosed in Peking Union Medical College Hospital and underwent MRgFUS ablation in Amcare Women's and Children's Hospital from August 2016 to October 2020 were retrospectively enrolled in this study.Clinical data of 66 UF patients were collected and compared between endometrial injury group and non-injury group.Stepwise regression was employed to determine the risk factors for the incident endometrial injury and 3-month endometrial injury.Multivariate logistic regression analysis was performed to explore the relationship of endometrial injury with age,pre-ablation tumor size,multiple UF,International Federation of Gynecology and Obstetrics(FIGO)classification,T2WI signal intensity,and treatment time.Results In terms of incident endometrial injury,the 66 patients included 41(62.1%)cases with no injury,4 cases(6.1%) with grade 1 injury,5 cases(7.6%)with grade 2 injury,and 16 cases(24.2%)with grade 3 injury.In terms of 3-month endometrial injury,the 66 patients included 49 cases(74.2%)with no injury,5 cases(7.6%)with grade 1 injury,2 cases(3.0%)with grade 2 injury,and 10 cases(15.2%)with grade 3 injury.Stepwise regression analysis indicated that FIGO classification was significantly associated with incident endometrial injury(B=-0.121,SE=0.045,ß=-0.326,t=-2.670,P=0.010)and 3-month endometrial injury(B=-0.125,SE=0.042,ß=-0.375,t=-2.989,P=0.004).Multivariate logistic regression analysis showed that FIGO classification was an independent risk factor for incident endometrial injury[OR=0.518(0.307-0.873),P=0.014]and 3-month endometrial injury[OR=0.456(0.253-0.824),P=0.009].Conclusions Endometrial injury could be controlled after MRgFUS ablation of UF and recover to some extent after 3 months.FIGO classification was an independent risk factor for both incident and 3-month endometrial injury.

A reappraisal of adult thoracic and abdominal surface anatomy via CT scan in Chinese population.

Accurate surface anatomy is essential for safe clinical practice. There are numerous inconsistencies in clinically important surface markings among and within contemporary anatomical reference texts. The aim of this study was to investigate key thoracic and abdominal surface anatomy landmarks in living Chinese adults using computed tomography (CT). A total of 100 thoracic and 100 abdominal CT scans were examined. Our results indicated that the following key surface landmarks differed from current commonly-accepted descriptions: the positions of the tracheal bifurcation, azygos vein termination, and pulmonary trunk bifurcation (all below the plane of the sternal angle at vertebral level T5-T6 in most individuals); the superior vena cava formation and junction with the right atrium (most often behind the 1st and 4th intercostal spaces, respectively); and the level at which the inferior vena cava and esophagus traverse the diaphragm (T10 and T11, respectively). The renal arteries were most commonly at L1; the midpoint of the renal hila was most frequently at L2; the 11th rib was posterior to the left kidney in only 29% of scans; and the spleen was most frequently located between the 10th and 12th ribs. A number of significant sex- and age-related differences were noted. The Chinese population was also compared with western populations on the basis of published reports. Reappraisal of surface anatomy using modern imaging tools in vivo will provide both quantitative and qualitative evidence to facilitate the clinical application of these key surface landmarks.

Application of single-bolus dual-source dual-energy CT urography in upper tract opacification and diagnostic performance for painless hematuria.

OBJECTIVE: To assess the upper urinary tract opacification and the diagnostic performance of one-bolus dual-source dual-energy CT urography (CTU) for painless hematuria. METHODS: Totally 205 patients who underwent dual-source dual-energy CTU for painless hematuria were enrolled in this study. CTU included true non-enhanced phase, dual-energy mode nephrographic phase, and FLASH mode excretory phase imaging of the urinary tract. Two radiologists independently evaluated the degree of upper urinary tract opacification. Prospective interpretations using true non-enhanced, nephrographic and excretory phase imaging for hematuria were recorded, as well as retrospective diagnosis using virtual non-enhanced, nephrographic and excretory phase imaging. The standard of reference included all available clinical, imaging, laboratory and follow-up data for up to 36 months after CTU exam. Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, and accuracy were calculated. Receiver-operating characteristic (ROC) analysis was undertaken and the area under the curve (AUC) calculated. The prospective and retrospective diagnostic performance for hematuria and the radiation dose of two CTU protocols were compared. RESULTS: It was found that 87.8% and 86.8% of segments were at least 50% opacified, respectively. The sensitivity, specificity, PPV, NPV and accuracy for hematuria for prospective interpretation were 95.2%, 91.9%, 98.2%, 81.0% and 94.6%, respectively. Comparable figures for retrospective diagnosis were 98.8%, 91.9%,98.2%, 94.4% and 97.6%. The AUC for prospective and retrospective diagnosis were 0.931±0.027 and 0.940±0.026, respectively (z=1.425, Bonferroni-corrected P>0.05). The radiation dose of the CTU protocol using in retrospective diagnosis[(12.732±3.485)mSv] was significantly lower than that of prospective diagnosis [(17.002±4.013)mSv] (P<0.05), with dose reduction of (32.74±8.92)%. CONCLUSION: One-bolus two-phase dual-source dual-energy CT urography provides at least 50% opacification of upper urinary tract segments and has high diagnostic performance for painless hematuria with relatively low radiation dose.

Quantitative hepatic CT perfusion measurement: comparison of Couinaud's hepatic segments with dual-source 128-slice CT.

PURPOSE: To compare the quantitative liver computed tomography perfusion (CTP) differences among eight hepatic segments. MATERIALS AND METHODS: This retrospective study was based on 72 acquired upper abdomen CTP scans for detecting suspected pancreas tumor. Patients with primary or metastatic liver tumor, any focal liver lesions except simple cyst (<3 cm in diameter), history of liver operation or splenectomy, evidence of liver cirrhosis or invasion of portal vein were excluded. The final analysis included 50 patients (M:F=21:29, mean age=43.2 years, 15-76 years). Arterial liver perfusion (ALP), portal-venous perfusion (PVP), total hepatic perfusion (THP=ALP+PVP), and hepatic perfusion index (HPI) of each hepatic segment were calculated and compared by means of one-way analysis of variance (ANOVA) and the Bonferonni correction method. RESULTS: Compared to hepatic segments 5, 6, 7 and 8, segments 2 and 3 showed a tendency of higher ALPs, lower PVPs, and higher HPIs, most of which were statistically significant (p<0.05). Hepatic segments 1 and 4 had higher mean values of ALP and HPI and lower mean values of PVP than segments 5, 6, 7 and 8 as well, although no significant differences were detected except for ALP and HPI for liver segments 1 and 7 (p=0.001 and 0.035 respectively), and ALP for liver segments 1 and 5 (p=0.039). Higher ALP and HPI were showed in hepatic segment 3 compared to segment 4 (p=0.000 and 0.000 respectively). No significant differences were found for THP among eight segments. CONCLUSIONS: Intra-hepatic perfusion differences exist in normal hepatic parenchyma especially between lateral sector (segments 2 and 3) and right lobe (segments 5, 6, 7 and 8). This might have potential clinical significance in liver-perfusion-related protocol design and result analysis.

[Computed tomographic angiography for evaluation of the relationship between coronary artery stenosis and head and neck artery stenosis].

OBJECTIVE: To evaluate the relationship between coronary artery stenosis and internal carotid artery, vertebral and basilar artery stenosis using computed tomographic angiography. METHODS: The imaging and clinical data of 84 patients who underwent coronary, head and cervical computed tomographic angiography in our hospital between September 2008 and June 2010 were retrospectively analyzed. Segment stenosis scoring was performed to quantify the degree of stenosis of coronary arteries. The relationship between the segment stenosis scoring and the degree of stenosis for internal carotid artery, vertebral and basilar artery was analyzed. RESULT: The coronary segment stenosis scores were significantly correlated with the degree of stenosis for internal carotid artery, vertebral and basilar artery (r=0.450 and 0.475,P<0.05) . CONCLUSION: The degree of the stenosis of coronary artery is associated with the stenosis of internal carotid artery, vertebral and basilar artery, which can be confirmed by computed tomographic angiography."

[Dual-energy computed tomographic angiography of head and neck arteries with different contrast material doses in second generation dual-source computed tomography system].

OBJECTIVE: To explore the feasibility of a dual-energy computed tomographic angiography (DECTA) protocol using test-bolus injection with reduction of contrast material (CM) dose in second generation dual-source CT system. METHODS: Totally 57 consecutive patients underwent CT angiography scan covering the cervical and cerebral arteries. CT was performed with second generation dual-source CT system. The time to peak (T) using a test-bolus injection was calculated. The patients were divided into three groups (A, B, and C) with different CM doses (40, 45, and 50 ml) and different delay time points [ (T+1) , (T+1) , and (T+2) s] . All the patients were followed by a 48 ml saline flush. Arterial enhancements were quantified by measuring attenuation values of the aortic arch, bifurcation of common carotid artery, contralateral internal jugular vein of the CM injection, superior vein cava, proximal middle cerebral artery, basilar artery, and straight sinus on source images. Visualizations of intracranial artery and ipsilateral venous effect of the CM injection were rated on a four-point grading scale on CTA images for qualitative assessment. RESULTS: Although the attenuation of internal jugular vein and straight sinus were significantly lower in group A than in groups B and C (P<0.05) , the attenuation of aortic arch, superior vein cava, common carotid artery, middle cerebral artery, and basilar artery vessels showed no significant differences among these three groups. The scores of the visualizations of intracranial artery and ipsilateral venous effect of the CM injection were also not significantly different among these three groups. CONCLUSION: Based on the delay time calculated by a test-bolus injection, a reduced-dose contrast material may provide an equal degree of arterial attenuation and a lower attenuation of vein for dual-energy CTA covering the craniocervical region in second generation dual-source CT system.

[Application of second generation dual-source computed tomography dual-energy scan mode in detecting pancreatic adenocarcinoma].

OBJECTIVE: To analyze the clinical value of multiple sequences derived from dual-source computed tomography (DSCT) dual-energy scan mode in detecting pancreatic adenocarcinoma. METHODS: Totally 23 patients with clinically or pathologically diagnosed pancreatic cancer were enrolled in this retrospective study. DSCT (Definition Flash) was used and dual-energy scan mode was used in their pancreatic parenchyma phase scan (100kVp/230mAs and Sn140kVp/178mAs) . Mono-energetic 60kev, mono-energetic 80kev, mono-energetic 100kev, mono-energetic 120kev, linear blend image, non-linear blend image, and iodine map were acquired. pancreatic parenchyma-tumor CT value difference, ratio of tumor to pancreatic parenchyma, and pancreatic parenchyma-tumor contrast to noise ratio were calculated. One-way ANOVA was used for the comparison of diagnostic values of the above eight different dual-energy derived sequences for pancreatic cancer. RESULTS: The pancreatic parenchyma-tumor CT value difference, ratio of tumor to pancreatic parenchyma, and pancreatic parenchyma-tumor contrast to noise ratio were significantly different among eight sequences (P<0.05) . Mono-energetic 60kev image showed the largest parenchyma-tumor CT value [ (77.53 ± 23.42) HU] , and iodine map showed the lowest tumor/parenchyma enhancement ratio (0.39?0.12) and the largest contrast to noise ratio (4.08 ± 1.46) . CONCLUSIONS: Multiple sequences can be derived from dual-energy scan mode with DSCT via multiple post-processing methods. Integration of these sequences may further improve the sensitivity of the multislice spiral CT in the diagnosis of pancreatic cancer.

[Clinical application of dual-source computed tomographic urography using dual-energy virtual non enhanced computed tomography].

OBJECTIVE: To evaluate the clinical feasibility of dual-source computed tomographic urography using dual-energy virtual non-enhanced CT. METHODS: Totally 240 patients received dual-source CT, which included true non-enhanced CT (TNCT) , nephrographic phase scanning with dual-energy mode (100kVp/230mAs and Sn140kVp/178mAs) , and excretory phase scanning. A contrast bolus injection of 100 ml (370 mgI/ml) contrast agent was applied (4.5ml/s) , followed by 100ml normal saline (4.5ml/s) . Virtual non-enhanced CT (VNCT) image sets were reformatted from 'Liver VNC ' software. The mean CT number, noise, signal to noise ratio (SNR) , image quality, and radiation dose were compared between TNCT and VNCT image sets. RESULTS: There was no significant difference in mean CT numbers of all organs (P>0.05) . However, VNCT images had significantly lower noise and higher SNR than TNCT images (both P<0.05) . Image quality of VNCT was lower than that of TNCT without significant difference (P>0.05) . Radiation dose of nephrographic phase with dual-energy mode was significantly higher than that of TNCT and excretory phase scanning (P<0.05) . CONCLUSION: Dual-energy VNCT requires less radiation dose and therefore has a potential to replace TNCT in the dual-source CT urography.

[Features of eight segments of liver perfusion with the second generation dual-source computed tomography].

OBJECTIVE: To explore the features of eight segments of liver perfusion with the second generation dual-source computed tomography (DSCT) . METHODS: Totally 15 patients with pancreatic endocrine diseases underwent abdominal CT perfusion with the second generation DSCT. The liver perfusion images were then transferred to workstation, and perfusion parameters were calculated, and then the artery liver perfusion (ALp) , portal-vein liver perfusion (pVp) , and hepatic perfusion index (HpI) of the eight hepatic segments were calculated. RESULTS: ALp was significantly different between segments 3, 4 and segments 5-8 (P<0.05) . pVp was significantly different between segments 2 and segments 6, 7 (P<0.05) . pVp and HpI were significantly different between segment 3 and segments 5-8 (P<0.05,P<0.01) . CONCLUSIONS: The second generation DSCT can be used to evaluate the perfusion conditions in all eight hepatic segments. The perfusion differs among eight segments of liver, which may be related with the anatomy of the liver vessels and the position of DSCT scanning. Its clinical significance needs further research.