Xenon computed tomography shows hemodynamic change during the progression of chronic hepatitis C

Aim: Xenon computed tomography (Xe-CT) is a non-invasive method of quantifying and visualizing tissue blood flow (TBF). Xe-CT allows separate measurement of hepatic arterial and portal venous flow. The aim of this study was to investigate correlations between the progression of fibrosis and hemodynamic changes in chronic hepatitis C (CHC) patients using Xe-CT. Methods: Separate measurements of portal venous TBF (PVTBF) and hepatic arterial TBF (HATBF) were performed using Xe-CT, and total hepatic TBF (THTBF) was calculated as the sum of PVTBF and HATBF. A total of 50 patients with CHC underwent Xe-CT. Liver biopsy was performed on 42 of the 50 patients, and hepatic fibrosis was classified as mild (F1), moderate (F2), severe (F3) or Child-Pugh class A cirrhosis (F4a). In addition, eight patients with Child-Pugh class B cirrhosis (F4b) were evaluated. Results: Significant negative correlations were identified between PVTBF and progression of stage (r(s) = -0.622, P < 0.0001) and between THTBF and progression of stage (r(s) = -0.458, P = 0.0041). Conclusion: Separate measurement of PVTBF and HATBF using non-invasive Xe-CT provided quantitative and visual information regarding hemodynamics of the entire liver in CHC patients. PVTBF decreases with the progression of fibrosis, even in CHC patients.     

Effect of Bronchial Thermoplasty on Air Trapping Assessed by Xenon Ventilation Computed Tomography

Objective Bronchial thermoplasty (BT) is a bronchoscopic procedure for patients with severe asthma. Although it has been suggested that BT works by reducing airway smooth muscle, the detailed mechanism underlying its effects is still unknown. Methods We performed xenon ventilation computed tomography (Xe-CT) before each BT procedure and six weeks after the third treatment to assess the improvement in lung ventilation at each separate lung region. The air trapping index in each lobe was defined as the mean trapping value (0: none, 1: mild, 2: moderate, and 3: severe) of the included segments. Patients and Materials Four patients were included. Results Asthma symptoms were improved after BT. The comparison of the scores at baseline with those after the third treatment showed that the air trapping index was improved in both the treated and untreated regions. However, neither the pulmonary function nor the exhaled nitric oxide was improved. Conclusion Using Xe-CT, we successfully evaluated the air trapping in patients who underwent BT. The improvement in asthma symptoms by BT may be related to the amelioration of peripheral lung ventilation in both the treated and untreated regions.     

无创正压通气对轻中度哮喘急性发作病人的治疗评估

目的探讨轻中度哮喘急性发作病人应用无创正压通气(NPPV)的临床疗效。方法32例支气管哮喘急性发作患者,随机分为治疗组和对照组,各16例在抗感染、平喘、激素等常规治疗的基础上,给予NPPV。多参数监护仪持续监测呼吸频率(RR)、心率(HR),血氧饱和度(SaO2),并在通气前、通气后30min,1、2h分别取其具体数值进行统计。结果治疗后30min、1h:RR、HR、SaO2的两组间差异均表现出显著性意义(P<0.05)。治疗后2h:两组的RR、HR、SaO2在监测数据上虽然有明的差异,但无统计学意义(P>0.05)。结论NPPV能迅速改善轻中度哮喘急性发作时的缺氧状态、缓解呼吸肌疲劳、临床症状明显缓解,患者耐受性好、乐于接受。     

Feasibility and accuracy of coronary imaging in elderly patients using the 64-row multi-detector computed tomography: a correlation study with conventional coronary angiography

Background Elderly patients generally have higher occurrence of coronary calcification, increased heart rate and difficulty with prolonged breath-holding. The aim of our study was to investigate the feasibility and accuracy of using 64-row multi-detector computed tomography (MDCT) in the assessment of coronary artery stenoses in elderly patients. Methods One hundred and fifty two patients with suspected or known coronary artery disease were divided into 4 groups according to their age (Group A: 40-49 years, n=34; Group B: 50-59 years, n=57; Group C: 60-69 years, n=48; Group D: 70 years and above; n=13). Coronary CT angiography (CTA) using a 64-row MDCT was performed and the findings were compared with that of conventional coronary angiography (CCA). Using axial images, multi-planar reconstructions (MPR) and maximum intensity projections (MIP), coronary segments of lumen diameter = 1.5mm were analyzed for the presence of significant stenosis (= 50% ). Results Percentages of poor image quality from coronary CTA preventing reliable correlations with CCA were 21%, 14%, 19% and 62% in Groups A to D respectively. Patients in Group D had significantly higher calcium scores compared with the other groups (P<0.001). In patients where CTA images were of acceptable quality, percentages of accurate correlations with CCA were 89.8%, 93.4%, 86.6% and 78.0% for Groups A to D respectively. There were no significant difference in serum creatinine, heart rate and contrast volume between the 4 groups. Conclusions The 64-row MDCT coronary angiography was less accurate and feasible for patients aged 70 years or above due to heavy coronary calcification and inability to perform a satisfactory breath-hold. However, a high diagnostic accuracy with the MDCT is possible in patients aged less than 70 years.(J Geriatric Cardiol 2006;3(1):9-14)     

Assessment of hepatic steatosis and hepatic tissue blood flow by xenon computed tomography in nonalcoholic steatohepatitis

Aim:  The diagnosis of non-alcoholic steatohepatitis (NASH) can be difficult using blood tests and imaging studies. Histological diagnosis by liver biopsy remains the gold standard of NASH diagnosis. There is an urgent need to develop and validate simple, reproducible, noninvasive tests to accurately assess NASH stage and grade. We assess the usefulness of xenon computed tomography (Xe-CT), as a non-invasive method of quantitatively and visually determining hepatic tissue blood flows (TBFs), and xenon solubility (λ value) simultaneously with TBF, in the evaluation of NASH pathophysiology.
Methods:  Histological severity of fatty changes and severity of fibrosis based on Brunt's classification were determined in 38 NASH patients. We evaluated correlations between the grade of fatty changes and λ value, and correlations between the stage of fibrosis and TBFs.
Results:  The λ value showed significant positive correlations with both grade of steatosis ( r  = 0.813, P  < 0.001) and each 10% range of histological fatty infiltration ( r  = 0.926, P  < 0.001). A significant negative correlation was seen between λ value and the liver : spleen ratio ( r  = −0.835, P  < 0.001). Portal venous tissue blood flow and total hepatic tissue blood flow showed significant negative correlations with the progression of fibrosis ( r  = −0.465, P  < 0.01; r  = −0.433, P  < 0.01, respectively). Total hepatic tissue blood flow tended to decrease with progressing grade of steatosis.
Conclusion:  Xe-CT offers a convenient and objective method for evaluating fatty infiltration and changes in blood flow in the entire liver, and appears useful for detailed evaluation of patients with NASH.     

Significance of three-dimensional computed tomography in a very old patient with sigmoid volvulus

With an increase in the aged population, a greater opportunity to face sigmoid volvulus is expected. We report sigmoid volvulus in a 90-year-old man with a 4-day history of increasing abdominal discomfort and distension. The reconstructed three-dimensional computed tomography (CT) clearly revealed the presence of sigmoid volvulus and the location of the twist. Using colonoscopy, the patient was successfully decompressed. Three-dimensional CT may be useful for diagnosis, choice of management, and elucidating etiology of sigmoid volvulus in the elderly.     

无创正压通气在重症支气管哮喘治疗中的价值

目的探讨无创正压通气在重症支气管哮喘治疗中的价值。方法观察重症支气管哮喘患者应用无创正压通气治疗前、治疗后血气指标及生理指标的变化,判断治疗效果。结果患者治疗后2h、24h、48h的血气指标（PH,PaO2,PaCO2）明显优于治疗前（P〈0．05）,治疗2天后生理指标改善明显。结论无创正压通气治疗重症哮喘临床疗效好,副作用少,值得广泛推广应用。     

多层螺旋CT在老年急性肺栓塞诊断及疗效评估中的价值

目的 探讨CT肺动脉造影（CTPA）对老年急性肺栓塞（PE）的诊断及疗效评估价值。方法 入选2009年1月至2015年1月在复旦大学附属华东医院心内科住院的老年急性PE患者55例,分为严重组（n＝24）和非严重组（n＝31）。比较两组患者在溶栓治疗前后右/左心室短轴最大径比（RV/LV）、上腔静脉最大径、肺动脉最大径及栓塞指数等指标。结果 与溶栓治疗前相比,严重组患者的RV/LV、上腔静脉最大径、肺动脉最大径及栓塞指数在治疗后均显著降低,差异均具有统计学意义（P＜0.05）;非严重组患者的肺动脉最大径和栓塞指数在治疗后显著降低,差异均具有统计学意义（P＜0.05）。结论 CTPA可用于PE的诊断,并能对溶栓后疗效进行评价,具有快速、有效、无创的优势。     

Multidetector-row computed tomography in the management of hepatocellular carcinoma with transcatheter arterial chemoembolization

With the introduction of spiral computed tomography and the development of novel imaging technology in recent years, multidetector-row computed tomography (MDCT) has increasingly been used for the diagnosis of various lesions, especially hepatocellular carcinoma (HCC), due to its volume acquisitions, short scanning time, and especially its double-phase scanning nature, which takes advantage of the dual blood supply of liver. Multidetector-row computed tomography is used to classify HCC into several types based on the blood supply and the histological characteristics of HCC. The evaluation of HCC by MDCT provides crucial clues for the doctors to adopt correct clinical management strategies such as the selection of the appropriate dose of lipiodol before transcatheter arterial chemoembolization (TACE) and the prediction of the prognosis of HCC after TACE. The MDCT scanning allows doctors to choose the region of interest and to evaluate the blood supply according to the lipiodol uptake in order to decide whether there is recrudescence and whether a repeated therapy should be taken. This review describes MDCT, its biphasic scanning, its evaluation of blood supply in HCC and the subsequent classification of HCC, its therapeutic significance before TACE and the prognostic value after TACE.     

Clinical yield of computed tomography brain scans in older general medical patients

OBJECTIVES: To evaluate the clinical yield of computed tomography (CT) brain scans in a prospective cohort of older patients admitted to the general medicine service. DESIGN: Nested cohort study of 117 subjects enrolled in previous prospective cohort study of 919 subjects. SETTING: University-affiliated teaching hospital. PARTICIPANTS: Hospitalized general medical patients aged 70 and older who received one or more brain CT scans during their hospital stay. MEASUREMENTS: Review of medical records and interpretation of the first brain CT scan in these 117 patients for indications for ordering scans and clinically significant brain abnormalities. Medical records of patients with brain CT scans with abnormalities were reviewed for 2 weeks after the scan for changes in medical management resulting from scan findings. Three independent reviewers adjudicated the presence of abnormalities and resulting treatment changes. RESULTS: Of the 117 brain CT scans, 32 (27%) were ordered to exclude intracranial hemorrhage, 30 (26%) to exclude cerebrovascular accident (CVA), 16 (14%) for falls, 15 (13%) for syncope, seven (6%) to exclude subdural hemorrhage, five (4%) for mental status change, and 12 (10%) for other reasons. Of the 117 brain CT scans, 29 (25%) had abnormalities, including acute CVA or hemorrhage, old CVA, meningioma, and other abnormalities. Only 10 (9% of all scans, 34% of abnormal scans) resulted in treatment changes (including consultations, further imaging, stroke evaluation, and drug changes). The presence of focal neurological deficits was significantly associated with treatment changes after CT scans (odds ratio=13.2, 95% confidence interval=1.7-161.5). CONCLUSION: These results suggest that the overall clinical yield of brain CT scans in unselected older hospitalized patients is low. Targeting scans toward patients with new focal neurological deficits will help to improve clinical yield.     

Differences in fluorodeoxyglucose positron emission tomography/computed tomography findings between elderly onset rheumatoid arthritis and polymyalgia rheumatica

Abstract

Objectives. To compare the fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) findings in patients with elderly-onset rheumatoid arthritis (EORA) with those in patients with polymyalgia rheumatica (PMR), two conditions with similar clinical presentations.

Methods. We retrospectively analyzed the FDG-PET/CT findings in 10 patients with EORA and 27 patients with PMR admitted to our department between 2006 and 2012.

Results: No significant difference was observed in the median patient ages at the time of FDG-PET/CT scans in the EORA and PMR groups (73.5 vs. 78.0 years, respectively). Significant differences in both FDG uptake scores and standardized uptake values were observed between the two groups in the ischial tuberosities, spinous processes, and wrists. No significant differences were detected in the shoulders and hips. However, specific uptake patterns were observed in each group: circular and linear uptake patterns were observed around the humeral head in the EORA group, whereas focal and non-linear uptake patterns were observed in the PMR group. Moreover, focal uptake in front of the hip joint, indicating iliopectineal bursitis, tended to be limited to the PMR group. High sensitivity (92.6%) and specificity (90%) were observed for PMR diagnoses when at least three of the following five items were satisfied: characteristic findings of shoulder and iliopectineal bursitis, FDG uptake in ischial tuberosities and spinal spinous processes, and lack of FDG uptake in the wrists.

Conclusion. The differences in the degree of uptake at each lesion and in uptake patterns at the shoulders and hips are potentially useful for obtaining a definitive diagnosis.     

Quantitative computed tomography detects peripheral airway disease in asthmatic children

The aim of this study was to compare air-trapping as quantified by high-resolution computed tomography (HRCT) of the chest with measures of lung function and airway inflammation in children with mild to moderate asthma. Plethysmography indices, respiratory resistance, and reactance before and after bronchodilator with impulse oscillation (IOS), exhaled nitric oxide (eNO), total eosinophil count (TEC), and serum eosinophil cationic protein (ECP) levels were measured in 21 subjects. A single-cut HRCT image at end-expiration was obtained. Air-trapping was quantified and expressed in terms of the pixel index (PI) by determining the percentage of pixels in lung fields below -856 and -910 Hounsfeld units (HU). Pairwise linear correlations between PI and other parameters were evaluated. Subjects had only mild airflow limitation based on prebronchodilator forced expiratory volume in 1 sec (FEV(1)), but were hyperinflated and had air-trapping based on elevated total lung capacity (TLC) and residual volume (RV)/TLC ratio, respectively. The PI at -856 HU was positively correlated with % predicted TLC, total gas volume (TGV), and ECP level, and was inversely correlated with FEV(1)/forced vital capacity (FVC) and % predicted forced expiratory flow between 25-75% FVC (FEF(25-75)). The PI at -910 HU correlated similarly with these variables, and also correlated positively with IOS bronchodilator reversibility. This data suggest that quantitative HRCT may be a useful tool in the evaluation of peripheral airflow obstruction in children with asthma.     

ASV模式机械通气治疗重症哮喘的临床研究

目的研究不同通气模式对重症哮喘患者的疗效。方法我院2011至2014收治的重症哮喘患者60人,随机分为A、B两组,分别给予同步间歇指令通气+压力支持通气(SIMV+PSV)及适应性支持通气(ASV),每组30人。比较两组患者呼吸力学指标,血气以及血清炎症因子水平。结果与SIMV+PSV组相比,ASV组的潮气量(VT)明显升高(P0.01),呼吸频率(RR)(P0.01)、气道峰压(Ppeak)(P0.05)、气道阻力(R)(P0.05)明显降低;ASV组的C反应蛋白(CRP)、降钙素原(PCT)、白介素-6(IL-6)、肿瘤坏死因子α(TNF-α)均明显低于SIMV+PSV组(P0.01)。ASV组患者上机时间明显缩短(P0.05)。结论ASV通气模式有利于降低重症哮喘患者的机体炎症反应,减少呼吸功并改善高通气力学,减少通气时间。     

无创正压通气间断雾化吸入在重症哮喘患者中的应用

目的对无创正压通气并经管道雾化吸入治疗重症哮喘的临床疗效进行研究。方法以95例住院治疗的重症哮喘患者为研究对象,随机分为研究组48例和对照组47例,研究组在常规治疗的基础上给予经鼻(面)罩无创正压通气并雾化吸入治疗,对照组给予单纯常规治疗,比较治疗后两组患者的临床疗效及治疗前后的血气情况。结果研究组总有效率为91.66%,明显高于对照组,两组相比差异有统计学意义(P<0.05),两组患者治疗前PH值、PaO2、PaCO2、SaO2及治疗后SaO2相比差异无统计学意义(P>0.05),而治疗后研究组PH值、PaO2及PaCO2得到了明显改善,两组相比差异有统计学意义(P<0.05)。结论无创正压通气并经管道雾化吸入治疗重症哮喘,提高了患者治疗的有效率,降低了并发症的发生率,值得临床推广应用。     

Intracranial cause of delirium: computed tomography yield and predictive factors

Background: Computed tomography (CT) of the brain in delirium investigation has a low yield of identifiable causes. We sought to identify the best clinical predictors of an intracranial cause of delirium. Methods: We performed a case–control study of patients admitted to a delirium unit. Clinical factors of patients with positive findings on scans were compared with those without demonstrated causes. The main outcome measure was intracranial abnormalities accountable for the cause of delirium. Results: During 18 months, there were 300 admissions to the unit. Mean age of patients was 86.6 years. Among 200 patients who proceeded to CT scanning, only 29 demonstrated intracranial pathology accountable for the cause of delirium, with a yield of 14.5%. There were 13 patients with ischaemic stroke, seven with subdural haemorrhage and nine with intracerebral haemorrhage. In multivariate analysis, new neurological deficits (adjusted odds ratio (OR) 18.17, 95% confidence interval (CI) 5.99–55.15), recent falls history (adjusted OR 5.58, 95% CI 1.90–16.42) and decline in conscious level (adjusted OR 4.58, 95% CI 1.33–15.79) were predictors of clinically meaningful radiological findings. Twenty‐six of the 29 patients with scans had these three predictors with a sensitivity of 89.7% (95% CI 78.6–100%). Conclusion: We identified a history of recent fall as a new independent predictor for clinically relevant intracranial pathology in delirious patients, besides new neurological deficits and decline in conscious state. A flow chart incorporating CT head scanning as part of delirium investigation is proposed.     

The use of B-type natriuretic peptide in the management of elderly patients with acute dyspnoea

OBJECTIVES: The aim of this study was to define the impact of B-type natriuretic peptide (BNP) levels on the management of elderly patients presenting with acute dyspnoea. DESIGN: We performed a prospective randomized controlled study in 269 elderly patients at least 70 years of age included in the B-type natriuretic peptide for Acute Shortness of breath Evaluation (BASEL) study. Patients were randomly assigned to a diagnostic strategy with (n = 136, BNP group) or without (n = 133, control group) the use of BNP levels provided by a rapid bedside assay. The time to discharge and the total cost of treatment were the primary end-points. RESULTS: Amongst elderly patients, baseline characteristics were well matched between both groups. The use of BNP levels significantly reduced the time to discharge (median 9.0 in the BNP group versus 11.0 days in the control group; P = 0.029). Total treatment cost was $5381 (95% CI, 4482-6280) in the BNP group when compared with $7411 (95% CI, 6180-8642; P = 0.009) in the control group. In addition, a significant reduction in 30-day mortality was observed (9% in the BNP group versus 17% in the control group; P = 0.039). CONCLUSIONS: Used in conjunction with other clinical information, rapid measurement of BNP in the emergency department improved the management of elderly patients presenting with acute dyspnoea and thereby reduced the time to discharge and the total treatment cost. In addition, BNP testing seemed to reduce 30-day mortality.     

Mechanical ventilation in children with severe asthma

Hospital admissions for childhood asthma have increased during the past few decades. The aim of this study was to describe the need for mechanical ventilation for severe asthma exacerbation in children in Finland from 1976 to 1995. We reviewed medical records and collected data retrospectively from all 5 university hospitals in Finland, thus covering the entire population of about 5 million. The endpoints selected were the number of admissions and readmissions leading to mechanical ventilation, duration of stay in the hospital, and mortality. Moreover, asthma medications prescribed prior to admission and administered in the intensive care unit (ICU), as well as the etiology of the exacerbation associated with mechanical ventilation were examined. Mechanical ventilation was required in 66 ICU admissions (59 patients). This constituted approximately 10% of all 632 admissions for acute asthma to an ICU. The number of admissions decreased from 1976 to 1995: 41 admissions between 1976 and 1985 vs. 25 admissions during the next 10-year period. The mean age at admission to the ICU was 3.6 years, and 46% of the patients were boys. Prior to the index admission, 70% of the patients had used asthma medication such as oral bronchodilator (50%), inhaled bronchodilator (20%), theophylline (38%), inhaled glucocorticoid (18%), oral glucocorticoid (5%), and cromoglycate (7%). Respiratory infection was by far the most common cause of all the exacerbations (61%), followed by food allergy (8%) and gastroesophageal reflux (3%). In 28% of cases the cause of the severe asthma exacerbation could not be identified. In the mechanically ventilated patients readmissions occurred 38 times between 1976 and 1985 vs. 5 times between 1986 and 1995. Five of the patients who received mechanical ventilation died, and in 3 of these patients asthma was the event causing death. In conclusion, there has been decrease in the number of first and repeat ICU admission for asthma requiring mechanical ventilation between 1970 and 1995. This trend occurred despite a simultaneous 5% yearly increase in hospital admissions for childhood asthma during these 2 decades.