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Erich W Russi

Publications and source records attributed to Erich W Russi.

At least 19 recordsLinked to original sources
PubMed2007

Glutathione S-transferase genotypes modify lung function decline in the general population: SAPALDIA cohort study.

BACKGROUND: Understanding the environmental and genetic risk factors of accelerated lung function decline in the general population is a first step in a prevention strategy against the worldwide increasing respiratory pathology of chronic obstructive pulmonary disease (COPD). Deficiency in antioxidative and detoxifying Glutathione S-transferase (GST) gene has been associated with poorer lung function in children, smokers and patients with respiratory diseases. In the present study, we assessed whether low activity variants in GST genes are also associated with accelerated lung function decline in the general adult population. METHODS: We examined with multiple regression analysis the association of polymorphisms in GSTM1, GSTT1 and GSTP1 genes with annual decline in FEV1, FVC, and FEF25-75 during 11 years of follow-up in 4686 subjects of the prospective SAPALDIA cohort representative of the Swiss general population. Effect modification by smoking, gender, bronchial hyperresponisveness and age was studied. RESULTS: The associations of GST genotypes with FEV1, FVC, and FEF25-75 were comparable in direction, but most consistent for FEV1. GSTT1 homozygous gene deletion alone or in combination with GSTM1 homozygous gene deletion was associated with excess decline in FEV1 in men, but not women, irrespective of smoking status. The additional mean annual decline in FEV1 in men with GSTT1 and concurrent GSTM1 gene deletion was -8.3 ml/yr (95% confidence interval: -12.6 to -3.9) relative to men without these gene deletions. The GSTT1 effect on the FEV1 decline comparable to the observed difference in FEV1 decline between never and persistent smoking men. Effect modification by gender was statistically significant. CONCLUSION: Our results suggest that genetic GSTT1 deficiency is a prevalent and strong determinant of accelerated lung function decline in the male general population.

Adult↗
PubMed2006

Lung-volume reduction surgery as an alternative or bridging procedure to lung transplantation.

BACKGROUND: In this study, we prospectively analyzed the functional outcome and the survival after lung-volume reduction surgery (LVRS) in patients with end-stage emphysema who were initially potential candidates for lung transplantation (LTX), and investigated the impact of LVRS on posttransplant course in patients who underwent LTX after LVRS. METHODS: Of the 216 patients who underwent LVRS between 1994 and 2005, 58 were potential candidates for LTX at the time of LVRS (age 65 years or younger, forced expiratory volume in 1 second 25% of predicted or less; LVRS/LTX group). Lung-volume reduction surgery was performed by means of video-assisted, bilateral stapled resection of target areas. During the same period, 31 patients underwent primary LTX for end-stage emphysema (LTX group). Spirometry, plethysmography, carbon monoxide diffusing capacity, 6-minute walking distance, and dyspnea score were assessed preoperatively and at predetermined times after operation. Survival analysis was performed by use of the Kaplan-Meier method. RESULTS: All the functional variables significantly improved after LVRS and peaked within the first year. Subjective improvement was observed for up to 5 years after LVRS, and 53% (31 of 58) of the patients were still alive and had not undergone transplantation after a median follow-up of 44 months. Fourteen percent (8 of 58) of the patients underwent secondary LTX because of progressive worsening of the respiratory function after a median bridging time between LVRS and LTX of 33 months. Postoperative recovery after transplantation and median survival time were comparable between the 8 patients of the LVRS/LTX group and the 31 patients of the LTX group (96.5 months versus 118.5 months, p = 0.9). CONCLUSIONS: Lung-volume reduction surgery can significantly improve symptoms and lung function in selected patients who are initially potential candidates for LTX. Lung-volume reduction surgery can allow the postponement of LTX for up to 4 to 5 years and does not impair the chances for a subsequent successful LTX.

Adult↗
PubMed2006

A continuous positive airway pressure trial as a novel approach to the diagnosis of the obstructive sleep apnea syndrome.

OBJECTIVES: Treatment of obstructive sleep apnea syndrome (OSA) is often delayed because polysomnography, the recommended standard diagnostic test, is not readily available. We evaluated whether the diagnosis of sleep apnea could be inferred from the response to a treatment trial with nasal continuous positive airway pressure (CPAP). DESIGN: Study on diagnostic accuracy. SETTING: Sleep-disorders clinic of a university hospital. PATIENTS: Seventy-six sleepy snorers consecutively referred for sleep apnea evaluation. INTERVENTIONS: CPAP treatment trial over 2 weeks as an initial diagnostic test in comparison with polysomnography, and treatment success over > or = 4 months. MEASUREMENTS AND RESULTS: The main outcome was diagnostic accuracy of the CPAP trial. The trial result was positive if the patient had used CPAP for > 2 h per night and wished to continue therapy. This suggested sleep apnea. The trial was evaluated in terms of predicting an obstructive apnea/hypopnea index (AHI) > 10/h during polysomnography performed for validation, and in terms of identifying sleep apnea patients treated successfully over > or = 4 months. Forty-four of 76 patients (58%) had sleep apnea as confirmed by an AHI > 10/h. The CPAP trial predicted sleep apnea with a sensitivity of 80%, a specificity of 97%, and positive and negative predictive values of 97% and 78%, respectively. In 35 of 76 sleep apnea patients (46%) with positive CPAP trial results, polysomnography could have been avoided. These patients were prescribed long-term CPAP therapy. After 4 months, 33 of 35 patients (94%) still used CPAP, and their symptoms remained improved. These patients were identified by the CPAP trial with positive and negative predictive values of 92% and 100%, respectively. CONCLUSIONS: In a selected population, a CPAP trial may help to diagnose OSA, to identify patients who benefit from CPAP, and to reduce the need for polysomnography.

Continuous Positive Airway Pressure↗
PubMed2006

Endobronchial ultrasonography for the quantitative assessment of bronchial mural structures in lung transplant recipients.

BACKGROUND: Endobronchial ultrasonography (EBUS) has been shown to be an adequate tool to visualize the laminar structure of the bronchial wall. The purpose of this study was to investigate the potential of EBUS to identify and quantitatively assess bronchial wall structures in lung transplant recipients. METHODS: EBUS was performed with a radial 20-MHz ultrasonic miniprobe in lung transplant recipients undergoing surveillance bronchoscopies. Sequential pictures were taken of the main bronchus (proximal of anastomosis) and proximal right intermedius bronchus or proximal left lower lobe bronchus (distal of anastomosis), respectively. From every localization, five slides were chosen. The quantitative assessment of the digitized pictures was done with the aid of image analysis software. In addition to the comparison of the different layers between patients with and without infection and rejection, respectively, the intraclass correlation coefficients (ICCs) of the different measurements were calculated. RESULTS: From 20 EBUS examinations performed in 10 lung transplant recipients, 200 slides were selected for quantitative assessment. A five-layer composition could be identified in all selected slides. The relative area of layer two (hypoechoic submucosal tissue) of the autologous part was significantly smaller in patients with graft rejection (p = 0.04) compared to patients without rejection, and significantly larger in patients with graft infection (p = 0.02) compared to patients without graft infection. The ICC values were calculated in 50 different slides in a subset of five consecutive patients (0.91, 0.95, 0.88, and 0.91 for layers 1, 2, 3, and 5 of the autologous and 0.70, 0.92, 0.88, and 0.84 for the allogeneic parts, respectively). CONCLUSIONS: EBUS enables to discriminate different layers of the bronchi in humans and to measure the thickness of these layers in a reproducible fashion. Therefore, EBUS may be used to investigate and quantify inflammatory alterations of bronchial wall structures in vivo.

Adult↗
PubMed2006

Pretransplantation bone disease in patients with primary pulmonary hypertension.

INTRODUCTION: Osteoporosis is a common condition in patients with end-stage lung disease, but little attention has been given to bone disease in patients with primary pulmonary hypertension (PPH). The purposes of this study were as follows: (1) to determine the prevalence of osteoporosis in patients with severe PPH before lung transplantation, (2) to investigate whether generally accepted risk factors for osteoporosis would play a role in this special group of patients, and (3) to determine whether there is an association between functional parameters and pretransplantion bone mass. DESIGN: A retrospective analysis of 18 consecutive patients with PPH accepted for lung transplantation at the University Hospital of Zurich. MEASUREMENTS AND RESULTS: Decreased bone mineral density (BMD) [T score <- 1.0] was found in 11 of 18 patients (61%) at the femoral neck (FN) and 13 of 18 patients (72%) at the lumbar spine (LS). We did not find a significant difference of BMD in a gender- or age-specific manner. Body mass index (BMI) correlated significantly with BMD and T score at the FN and WT. Pulmonary vascular resistance (PVR) was notably linked with BMD at the FN. We found a positive association between walking distance in the 12-min walking test and BMD at the FN and WT. CONCLUSIONS: Low bone density is a very frequent condition in patients with severe PPH. In contrast to the general population, in our study group neither age nor female gender were significantly associated with lower bone mass. Body weight and BMI were highly coupled with BMD. Among the functional parameters, walking distance and PVR were correlated to BMD at the FN. Considering that patients with PPH may have an improved life expectancy in the future, the early diagnosis, prevention, and treatment of osteoporosis should receive high priority.

Adult↗
PubMed2006

The BODE index after lung volume reduction surgery correlates with survival.

STUDY OBJECTIVE: A recently introduced, multidimensional index called BODE (body mass index [BMI], degree of airflow obstruction assessed by spirometry, grade of dyspnea, and exercise capacity), quantified by 6-min walking distance (6MWD), has excellent predictive power with respect to outcome in COPD. We investigated whether the BODE index is able to predict survival after lung volume reduction surgery (LVRS). DESIGN: Retrospective study. SETTING: Tertiary university hospital. PATIENTS: One hundred eight-six COPD patients (76 women) with severe emphysema (mean +/- SD age, 64 +/- 8 years; mean FEV(1), 28 +/- 8% of predicted). INTERVENTION: Bilateral thoracoscopic LVRS. MEASUREMENTS AND RESULTS: BMI, pulmonary function, 6MWD, and the modified Medical Research Council dyspnea score were assessed before and 3 months after LVRS, and the BODE index was calculated. The patients were followed up with respect to survival for a median time of 40 months (range, 3 to 116 months) after surgery. The mean BODE index decreased from 7.2 +/- 1.6 preoperatively to 4.0 +/- 2.0 at 3 months after LVRS (p < 0.001). The postoperative but not the preoperative BODE correlated with survival, although preoperative patient characteristics were comparable between short-term (< 5 years) and long-term (> 5 years) survivors. A decrease to a lower BODE score class was associated with a reduced mortality (hazard ratio, 0.497, 95% confidence interval, 0.375 to 0.659; p < 0.001). The C statistic for the ability of the BODE index to predict the risk of death was larger (0.74) than that for the FEV(1) (0.63), the degree of dyspnea (0.64), or the 6MWD (0.62). CONCLUSIONS: The postoperative BODE index is a powerful predictor of survival in COPD patients after LVRS.

Aged↗
PubMed2005

Diffuse idiopathic neuroendocrine cell hyperplasia causing severe airway obstruction in a patient with a carcinoid tumor.

We report a 57-year-old female with severe airway obstruction who underwent resection of a tumor of unknown dignity during lung volume reduction surgery. The nodule consisted of a well-differentiated neuroendocrine tumor (carcinoid), and severe chronic obstructive lung disease was due to diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, a very rare cause of obliterative bronchiolitis. Radionuclide ablative therapy of the neuroendocrine tissue was considered but not found to be feasible due to a low lung/background ratio of the radiotracer.

Airway Obstruction↗
PubMed2005

Quality of life, physical disability, and respiratory impairment in Duchenne muscular dystrophy.

RATIONALE: Duchenne muscular dystrophy (DMD) leads to progressive, generalized paresis, and to respiratory failure in the second decade of life. The assumption that severe physical disability precludes an acceptable quality of life is common, but has not been specifically evaluated in DMD. OBJECTIVES: The purpose of this study was to investigate the quality of life in relation to physical disability, pulmonary function, and the need for assisted ventilation in DMD. METHODS: In 35 patients with DMD, aged 8-33 yr, we assessed physical disability by a score ranging from 9 (no disability) to 80 (complete dependence on care and technical aids), pulmonary function, and health-related quality of life by Short-Form 36 of the medical outcome questionnaire. MEASUREMENTS AND MAIN RESULTS: All patients required a wheelchair and help for dressing and eating. Fourteen patients were on long-term noninvasive positive-pressure ventilation. In ventilated patients, mean +/- SD FVC was 12 +/- 10 % predicted, and the physical disability score was 65 +/- 7. Corresponding values in spontaneously breathing patients were 48 +/- 25 % predicted, and 51 +/- 7, respectively (p < 0.05 for both comparisons between groups). Short-Form 36 physical function scores were massively reduced in both groups (1 +/- 2, and 0 +/- 0, respectively), but vitality, role-emotional, social function, and mental health scores were nearly normal (67-98), and did not differ between groups. CONCLUSIONS: Quality of life in DMD is not correlated with physical impairment nor the need for noninvasive positive-pressure ventilation. The surprisingly high quality of life experienced by these severely disabled patients should be taken into consideration when therapeutic decisions are made.

Activities of Daily Living↗
PubMed2005

Variability in densitometric assessment of pulmonary emphysema with computed tomography.

OBJECTIVES: The objectives of this study were to investigate whether computed tomography (CT) densitometry can be applied consistently in different centers; and to evaluate the reproducibility of densitometric quantification of emphysema by assessment of different sources of variation, ie, intersite, interscan and inter- and intraobserver variability, in comparison with intersubject variability. MATERIALS AND METHODS: In 5 different hospitals, 119 patients with emphysema were scanned using standardized protocols. In each site, an observer performed a quantitative densitometric analysis (including blood recalibration) on the corresponding patient group (n=23-25) and one observer analyzed the entire group of 119 patients. After several months, the latter observer analyzed all data for a second time. Subsequently, different sources of variation were assessed by variance component analysis with and without volume correction of the data. RESULTS: Inter- and intraobserver variability marginally contributes to the total variability (<0.001%). The interscan variability was 0.02% of the total variation after application of volume correction. The intersite variability was 48% as a result of one deviating CT scanner. Air recalibration normalized deviating air densities in CT scanners. Within sites, the intersubject variability ranged between 93% and 99% based on the analysis of 2 subsequent CT scans of the patients. CONCLUSIONS: Almost all variability in the density measurement of emphysema originates from differences between scanners and from differences in severity of emphysema between patients. Lung densitometry with multislice CT scanners is a highly reproducible measurement, especially if corrected for lung volume, because this reduces interscan variability.

Absorptiometry, Photon↗
PubMed2005

Inflammation patterns in allogeneic and autologous airway tissue of lung transplant recipients.

Inflammatory injuries directed toward airway structures play a key role in lung allograft rejection. However, data relating to the inflammation patterns of large airways are scarce and, in particular, the relation between autologous and allogeneic parts is unknown. For the first time, in this study, simultaneously collected endobronchial biopsies from the main (autologous) and upper lobe (allogeneic) carina of lung transplant recipients were assessed immunohistologically. A total of 27 pairs of EBBs were taken. Twelve endoscopies documented acute rejection and four examinations of patients with BOS were performed. Patients with acute rejection had more CD8-positive cells in the allogeneic parts compared with patients without acute rejection. Patients with BOS had more CD4- and CD45-positive cells in the autologous airways than stable patients. We conclude that distinct inflammatory changes do occur in large airways of lung transplant recipients and are not limited to the donor parts of airways.

Adult↗
PubMed2005

Psychosocial situation and physical health in 50 patients > 1 year after lung transplantation.

BACKGROUND: Lung transplants have been performed worldwide since the early 1980s. While numerous studies have been published on somatic aspects after lung transplantation, there is considerably less information available on psychosocial aspects and on the correlation between the physical and the psychosocial state of health after transplantation. METHODS: Between 1992 and 2002, 125 patients underwent lung transplantation at University Hospital Zurich. To be included into the study, patients had to have received a lung transplant > 12 months previously and to have good knowledge of the German or Italian languages. With the aid of standardized questionnaires, psychosocial variables such as levels of anxiety and depression, self-esteem, and social support were determined. In addition, self-assessments of physical and psychological health were obtained. The medical data included information on FEV1, complications such as pulmonary infections, acute or chronic allograft rejection, and assessment of the patient's physical and psychological health by the treating doctors. RESULTS: The overall degree of anxiety and depression of the lung transplant recipients was comparable to standard samples of an average population. However, male lung transplant recipients were significantly more depressed than female recipients. Self-esteem was higher than in clinical comparison samples. Preceding pulmonary complications had long-lasting effects on the level of anxiety, whereas nonpulmonary complications did not have such an effect. CONCLUSIONS: Overall, the psychological well-being of patients after lung transplantation is similar to the normal population. Subgroups of patients with increased psychological distress have been identified.

Adult↗
PubMed2005

Transtracheal high-flow insufflation supports spontaneous respiration in chronic respiratory failure.

STUDY OBJECTIVES: Transtracheal insufflation of oxygen-enriched air at a high flow rate has been proposed to support ventilation. The purpose of this study was to investigate the physiologic effects of high-flow insufflation unobtrusively with a respiratory inductive plethysmograph in patients with chronic respiratory failure. Using a respiratory inductive plethysmograph also permitted monitoring of end-expiratory lung volume, and respiratory variables could be quantified independently of the tracheal bias flow. DESIGN: Prospective randomized comparison of low-flow vs high-flow transtracheal insufflation. SETTING: Pulmonary division of a tertiary teaching hospital. PATIENTS: Fourteen spontaneously breathing outpatients with chronic hypoxemic respiratory failure carrying a transtracheal catheter for long-term oxygen therapy. INTERVENTIONS AND MEASUREMENTS: Oxygen-enriched air (fraction of inspired oxygen, 0.37) at 15 L/min and oxygen at 1.5 L/min were transtracheally administered for 1 h each. The breathing pattern and the end-expiratory lung volume were monitored by inductive plethysmography along with pulse oximetry and transcutaneous PCO2. Arterial blood gases were also analyzed at the end of the hour of both low-flow and high-flow insufflation. RESULTS: High-flow insufflation decreased the mean (+/- SEM) minute ventilation (Ve) by 20% from 8.37 +/- 0.49 to 6.66 +/- 0.57 L/min, the mean respiratory rate from 19.2 +/- 0.9 to 15.7 +/- 1.0 breaths/min, while mean expiratory time increased from 2.0 +/- 0.1 to 2.8 +/- 0.2 s, and end-expiratory lung volume decreased by 0.55 +/- 0.15 L compared to low-flow oxygen insufflation (p < 0.05 for all comparisons). Mean arterial and transcutaneous PCO2 decreased from 45 +/- 1 to 43 +/- 1 mm Hg and from 54 +/- 2 to 53 +/- 2 mm Hg, respectively (p < 0.05 in both instances), while arterial PaO2 and oxygen saturation did not change. CONCLUSIONS: High-flow transtracheal insufflation of oxygen-enriched air assists ventilation by reducing Ve without compromising gas exchange and by reducing end-expiratory lung volume, possibly through the reversal of dynamic hyperinflation.

Adult↗
PubMed2005

Iron accumulation in lung allografts is associated with acute rejection but not with adverse outcome.

BACKGROUND: Iron content in lung allografts is increased after transplantation. It was hypothesized that this may lead to fibrosis and posttransplant bronchiolitis obliterans syndrome (BOS). METHODS: In a prospective study, we evaluated 399 BAL fluid (BALF) and transbronchial lung biopsy samples obtained concurrently from 72 consecutive lung transplant recipients. RESULTS: The hemosiderin scores (HSs) of the BALF samples increased steadily during the postoperative period (p < 0.001). Patients with at least one acute rejection episode (AR) grade > or = A2 event had higher mean HSs, the difference being significant after the second (p < 0.008) and the sixth postoperative months (p < 0.05). The HS correlated with the number of ARs (p < 0.004), and it significantly increased after the first AR (p < 0.04). Except for oral anticoagulation, no other risk factors for elevated iron content were found. There was no correlation between HS or number of ARs and the development of BOS or survival, respectively. CONCLUSIONS: Progressive iron accumulation in lung allografts seems to be caused mainly by an AR, possibly due to perivascular leakage of erythrocytes. Neither increased HS nor the frequency of ARs were risk factors for subsequent development of BOS. Early detection and treatment of ARs might uncouple their association with BOS.

Acute Disease↗
PubMed2004

Effects of sinus surgery in patients with cystic fibrosis after lung transplantation: a 10-year experience.

Chronic infectious rhinosinusitis with Pseudomonas aeruginosa is common in cystic fibrosis and may result in allograft infection after lung transplantation. Sinus surgery followed by nasal care may reduce these adverse effects. Sinus surgery was performed in 37 patients with cystic fibrosis after transplantation. Bacteriology of sinus aspirates (n=771) and bronchoalveolar lavage (BAL) (n=256) was correlated with clinical data. Sinus surgery was successful in 54% and partially successful in 27% of patients. A significant correlation between negative sinus aspirates and negative BAL and between positive sinus aspirates and positive BAL (P<0.0001) was found. Successful sinus management led to a lower incidence of tracheobronchitis and pneumonia (P=0.009) and a trend toward a lower incidence of bronchiolitis obliterans syndrome (P=0.23). Sinus surgery followed by daily nasal douching may control posttransplant lower airway colonization and infection. In the long term, this concept may lead to less bronchiolitis obliterans syndrome by decreasing bronchiolar inflammation.

Adolescent↗
PubMed2004

Long-term results after lung volume reduction surgery in patients with alpha1-antitrypsin deficiency.

BACKGROUND: The favorable effects of lung volume reduction surgery for selected patients with smoker's emphysema has been demonstrated. However, outcome data for patients with alpha(1)-antitrypsin deficiency emphysema are scarce. METHODS: We prospectively studied pulmonary function, dyspnea, and 6-minute walking distance in 21 patients with severe alpha(1)-antitrypsin deficiency emphysema (PiZZ 18, PiZO 1, PiSZ 2, 10 female patients, median age 56 years, range 38-74 years) for as long as 5 years after thoracoscopic lung volume reduction surgery. RESULTS: Lung volume reduction surgery improved the mean dyspnea score, from 3.7 +/- 0.1 preoperatively to 1.4 +/- 0.2 at 3 months; the score remained improved for as long as 3.5 years. Mean vital capacity (% predicted) improved from 79% +/- 4.4% to 98% +/- 4.8% at 3 months, and the ratio of residual volume to total lung capacity decreased from 0.67 to 0.51. These improvements lasted for as long as 2 years. The mean airflow obstruction (forced expiratory volume in 1 second % predicted) improved from 27% +/- 1.9% to 38% +/- 3.3% at 3 months and remained statistically improved for 1 year. Four patients showed long-term improvement in lung function for as long as 3.5 years. These patients had markedly heterogeneous emphysema and showed no radiologic signs of airway inflammation. CONCLUSIONS: Lung volume reduction surgery in patients with advanced emphysema from alpha(1)-antitrypsin deficiency results in a significant improvement in dyspnea and lung function for as long as 3.5 years in some cases. It appears that magnitude and duration of these effects are inferior and shorter than those in patients with pure smoker's emphysema. Patients with heterogeneous disease and no or minor inflammatory airway disease may benefit most.

Adult↗
PubMed2004

Variability of inspiratory conductance quantifies flow limitation.

In the present study, our aim was to investigate whether the variability of conductance over the course of inspiration reflects flow limitation. Pressure/flow conditions in the upper airway were modelled by a collapsible tube within a rigid chamber and a pump simulating respiration. Instantaneous conductance was estimated every 20 ms as flow/resistive pressure, and its variability during inspiration expressed as the 90th/50th percentile ratio. Accuracy of this ratio to quantify flow limitation was evaluated by observing whether it changed predictably with adjustments of model parameters. To illustrate the potential of this ratio to quantify flow limitation in a clinical setting, we recorded pneumotachographic airflow and oesophageal pressure in 11 patients with obstructive sleep apnoea during nasal continuous positive airway pressure (CPAP) ventilation, and observed changes in the 90th/50th percentile ratio of inspiratory lung conductance induced by mask pressure titration. Rising pressure surrounding the collapsible tube from subatmospheric to positive values induced progressive inspiratory collapse and increased 90th/50th percentile ratios of inspiratory conductance as predicted. Changes in flow limitation induced by other model modifications were also correctly tracked by the 90th/50th conductance percentile ratio. Increasing mask pressure during CPAP ventilation in sleep apnoea patients from subtherapeutic to therapeutic pressure levels was associated with the expected decrease in the 90th/50th percentile ratio of inspiratory lung conductance from a mean of 6.5+/-3.1 to 1.6+/-0.3 ( P <0.001). We conclude that variability of inspiratory conductance quantified by the 90th/50th percentile ratio may serve as a measure of flow limitation that is independent of the absolute value of conductance.

Airway Resistance↗
PubMed2004

Comparison of the sensitivities of 5 different computed tomography scanners for the assessment of the progression of pulmonary emphysema: a phantom study.

RATIONALE AND OBJECTIVES: To compare the sensitivities of 5 different computed tomography scanners (4 multislice CT [MSCT] and 1 single-slice CT) in the assessment of the progression of pulmonary emphysema. METHODS: A Perspex cylinder phantom was constructed containing small pieces of polythene foam with densities representative of lung. Changing the cylinder's volume simulated subtle lung density changes. The sensitivity to density changes was defined by the variation in the residual errors from the linear regression line between time and density. RESULTS: The single-slice CT scanner was significantly less sensitive to density changes than MSCT scanners. Also, among MSCT scanners, small but significant differences were found when the standardized acquisition protocol was used. CONCLUSIONS: Considering the large sensitivity differences between single- and multislice CT scanners, we would recommended using MSCT scanners in clinical multicenter trials in emphysema. The protocol standardization of MSCT scanners can still be further improved.

Humans↗