Racial attention deficit.

Despite efforts toward equity in organizations and institutions, minority members report that they are often ignored, their contributions undervalued. Against this backdrop, we conduct a large-sample, multiyear experimental study to investigate patterns of attention. The findings provide causal evidence of a racial attention deficit: Even when in their best interest, White Americans pay less attention to Black peers. In a baseline study, we assign an incentivized puzzle to participants and examine their willingness to follow the example of their White and Black peers. White participants presume that Black peers are less competent­and fail to learn from their choices. We then test two interventions: Providing information about past accomplishments reduces the disparity in evaluations of Black peers, but the racial attention deficit persists. When Whites can witness the accomplishments of Black peers, rather than being told about them, the racial attention deficit subsides. We suggest that such a deficit can explain racial gaps documented in science, education, health, and law.

Stereotactic body radiotherapy for the treatment of oligometastatic gynecological malignancy in the abdomen and pelvis: A single-institution experience.

PURPOSE/OBJECTIVES: Metastasis-directed therapy with stereotactic body radiotherapy (SBRT) in the setting of oligometastatic disease is a rapidly evolving paradigm given ongoing improvements in systemic therapies and diagnostic modalities. However, SBRT to targets in the abdomen and pelvis is historically associated with concerns about toxicity. The purpose of this study was to evaluate the safety and efficacy of SBRT to the abdomen and pelvis for women with oligometastases from primary gynecological tumors. MATERIALS/METHODS: From our IRB-approved registry, all patients who were treated with SBRT between 2014 and 2020 were identified. Oligometastatic disease was defined as 1 to 5 discrete foci of clinical metastasis radiographically diagnosed by positron emission tomography (PET) and/or computerized tomography (CT) imaging. The primary endpoint was local control at 12 months. Local and distant control rates were estimated using the Kaplan-Meier method. Time intervals for development of local progression and distant progression were calculated based on follow up visits with re-staging imaging. Acute and late toxicity outcomes were determined based on Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. RESULTS: We identified 34 women with 43 treated lesions. Median age was 68 years (range 32-82), and median follow up time was 12 months (range 0.2-54.0). Most common primary tumor sites were ovarian (n=12), uterine (n=11), and cervical (n=7). Median number of previous lines of systemic therapy agents at time of SBRT was 2 (range 0-10). Overall, SBRT was delivered to 1 focus of oligometastasis in 29 cases, 2 foci in 2 cases, 3 foci in 2 cases, and 4 foci in 1 case. All patients were treated comprehensively with SBRT to all sites of oligometastasis. Median prescription dose was 24 Gy (range 18-54 Gy) in 3 fractions (range 3-6) to a median prescription isodose line of 83.5% (range 52-95). Local control by lesion at 12 and 24 months was 92.5% for both time points. Local failure was observed in three treated sites among two patients, two of which were at 11 months in one patient, and the other at 30 months. Systemic control rate was 60.2% at 12 months. Overall survival at 12 and 24 months was 85% and 70.2%, respectively. Acute grade 2 toxicities included nausea (n=3), and there were no grade > 3 acute toxicities. Late grade 1 toxicities included diarrhea (n=1) and fatigue (n=1), and there were no grade > 2 toxicities. CONCLUSION: SBRT to oligometastatic gynecologic malignancies in the abdomen and pelvis is feasible with encouraging preliminary safety and local control outcomes. This approach is associated with excellent local control and low rates of toxicity during our follow-up interval. Further investigations into technique, dose-escalation and utilization are warranted.

Airflow limitation as a risk factor for vascular stiffness.

BACKGROUND: Cardiovascular disease is one of the main causes of mortality in patients with chronic obstructive pulmonary disease (COPD), and atherosclerosis is a cause of cardiac comorbidities in COPD. However, it is not clear whether airflow limitation is associated with atherosclerosis irrespective of smoking.OBJECTIVE: To investigate whether airflow limitation is independently associated with vascular stiffness.METHODS: We enrolled 18 893 participants (male 70.5%; mean age 47.5 ± 9.8 years; never smokers 44.2%) who underwent spirometry and brachial-ankle pulse wave velocity (baPWV) as part of a standard health examination at Ajou University Hospital, Suwon, South Korea, from January 2010 to December 2015.We defined vascular peripheral atherosclerosis as baPWV ≥ 1400 cm/s and airflow limitation as pre-bronchodilator ratio of forced expiratory volume in 1 sec (FEV1) to forced vital capacity (FVC) <70%.RESULTS: Mean baPWV was higher in subjects with airflow limitation (1477.6 ± 331.7 cm/sec, n = 638) than in those without airflow limitation (1344.1 ± 231.8 cm/sec, n = 18255, P < 0.001). In multivariate logistic regression analysis, the following were independent predictors associated with peripheral atherosclerosis (P < 0.05): age, male sex, fasting serum glucose, mean blood pressure, serum leukocyte count, serum low density lipoprotein level and FEV1.CONCLUSION: Airflow limitation was an independent predictor of vascular stiffness irrespective of smoking history, which suggests that airflow limitation is linked with atherosclerosis.

CXCR3 ligands in pleural fluid as markers for the diagnosis of tuberculous pleural effusion.

SETTING: A tertiary care academic medical centre. OBJECTIVE: To evaluate the clinical usefulness of C-X-C motif chemokine receptor 3 (CXCR3) ligands in tuberculous pleural effusion (TPE). DESIGN: We recruited 336 patients with pleural effusion due to various causes. Concentrations of interferon-gamma (IFN-γ) and the CXCR3 ligands CXCL9 and CXCL11 were determined using enzyme immunoassays; adenosine deaminase (ADA) activity was measured in pleural fluid and serum. RESULTS: TPE was diagnosed in 106 patients. Non-TB conditions included lung cancer (n = 95), para-pneumonic effusion (n = 52), non-lung malignancy (n = 30), other exudate (n = 24) and transudate (n = 29) disorders. All marker levels in serum samples and pleural fluid were significantly higher in the TPE group. Analyses of receiver operating characteristic curves for differentiating TPE from non-TB effusions produced the following results for the area under the curve (AUC) for CXCL9, CXCL11, IFN-γ and ADA, respectively: 0.982, 0.952, 0.982, and 0.952. Marker AUCs in lymphocytic exudates were also high. Combining the levels of CXCL9, IFN-γ and ADA in pleural fluid improved the diagnostic performance. Serum levels of CXCL9 had the highest AUC (0.848) for diagnosing TPE. CONCLUSION: Levels of CXR3 ligands in pleural effusion are useful for diagnosing TPE.

Serum CXCR3 ligands as biomarkers for the diagnosis and treatment monitoring of tuberculosis.

SETTING: Tertiary care academic medical centre. OBJECTIVE: To evaluate the clinical utility of CXC chemokine receptor 3 (CXCR3) ligands in the diagnosis and monitoring of tuberculosis (TB). DESIGN: Presumptive TB patients (active TB, 256; non-TB disease, 52) and 201 healthy controls were enrolled. The serum levels of interferon-gamma (IFN-γ) and CXCR3 ligands (CXCL9, a monokine induced by IFN-γ [MIG] and CXCL11, an IFN-inducible T-cell α chemoattractant [I-TAC]) were measured using enzyme-linked immunosorbent assay. An IFN-γ release assay (IGRA) was also performed. Serial samplings were performed in 19 TB patients at baseline and at 1, 2, 3, 6 and 12 months after treatment initiation. RESULTS: All marker levels were higher in TB patients than in controls and non-TB patients. The area under the curve (AUC) for differentiating between all TB patients and controls was 0.96 (95%CI 0.94-0.98) for CXCL9, 0.84 (95%CI 0.80-0.87) for CXCL11 and 0.61 (95%CI 0.57-0.66) for IFN-γ. CXCL9 levels afforded particularly high discriminatory power between TB patients and IGRA-positive controls (AUC = 0.95, 95%CI 0.92-0.97). The levels of CXCR3 ligands decreased significantly during follow-up, and these changes were correlated with treatment response. CONCLUSION: CXCR3 ligands CXCL9 and CXCL11 may be useful surrogate markers for the diagnosis and follow-up of TB.

CXCR3 ligands as clinical markers for pulmonary tuberculosis.

SETTING: A tertiary care academic medical centre. OBJECTIVE: To evaluate the clinical usefulness of CXC chemokine receptor 3 (CXCR3) ligands in active pulmonary tuberculosis (TB). DESIGN: Patients with various pulmonary diseases and healthy controls were recruited into this cross-sectional study. Plasma levels of interferon-gamma (IFN-γ) and the CXCR3 ligands (CXCL9 [monokine induced by IFN-γ, MIG], CXCL10 [IFN-γ-inducible 10-kDa protein, IP-10] and CXCL11 [IFN-inducible T-cell α chemoattractant, I-TAC] were measured using enzyme immunoassays. RESULTS: The study included 846 subjects: 201 patients with active pulmonary TB, 389 with other pulmonary diseases, and 256 controls. CXCR3 ligand levels were higher in TB patients than in controls and all other disease groups, whereas the IFN-γ levels did not differ. The area under the curve (AUC) for differentiating active TB from all other groups was 0.797 for CXCL9, 0.726 for CXCL10, 0.846 for CXCL11 and 0.534 for IFN-γ. The AUC for differentiating active TB from controls was 0.926 for CXCL9, 0.818 for CXCL10, 0.865 for CXCL11 and 0.575 for IFN-γ. CXCR3 levels correlated with sputum acid-fast bacilli smear grades and the radiographic extent of pulmonary TB. CONCLUSION: CXCR3 ligands may be useful surrogate markers for diagnosing active TB and for assessing TB patients clinically.

The Model for End-stage Liver Disease score is potentially a useful predictor of hyperkalemia occurrence among hospitalized angiotensin receptor blocker users.

WHAT IS KNOWN AND OBJECTIVE: Angiotensin receptor blockers (ARBs) are medications commonly used for treating conditions such as hypertension. However, ARBs are frequently associated with hyperkalemia, a potentially critical adverse event, in high-risk patients. Although both the liver and the kidney are major elimination routes of ARBs, the relationship between hepatorenal function and ARB-related hyperkalemia has not yet been investigated. The purpose of this study was to evaluate the risk of hyperkalemia, in terms of various hepatorenal functions, for hospitalized patients newly initiated on ARB treatment. METHODS: We evaluated ARB-related hyperkalemia in a cohort of 5530 hospitalized patients, who had not previously used ARBs, between 12 April 2004 and 31 May 2012. Hepatorenal function was assessed by the Model for End-stage Liver Disease (MELD) score. Hyperkalemia risk was assessed by hepatorenal function, risks were categorized into the four MELD scoring groups, and the groups were compared with one another. RESULTS AND DISCUSSION: The MELD score was significantly different between the hyperkalemic and non-hyperkalemic groups (independent t-test, P < 0.001). The MELD score 10-14, 15-19 and ≥ 20 groups showed higher risks of hyperkalemia than the lowest MELD score group {log-rank test, P < 0.001; multiple Cox proportional hazard model, hazard ratios 1.478 (P = 0.003), 2.285 (P < 0.001) and 3.024 (P < 0.001), respectively}. WHAT IS NEW AND CONCLUSION: The MELD score showed a stronger predictive performance for hyperkalemia than either serum creatinine or estimated glomerular filtration rate alone. Furthermore, the MELD score showed good predictive performance for ARB-related hyperkalemia among hospitalized patients. The clinical implications and reasons for these findings merit future investigation.

Emphysematous phenotype is an independent predictor for frequent exacerbation of COPD.

SETTING: Frequent exacerbation is an important phenotype in chronic obstructive pulmonary disease (COPD), while emphysema is associated with many comorbidities and lung function decline. OBJECTIVE: To investigate unique features of frequent exacerbators and test the hypothesis that emphysematous phenotype is associated with frequent exacerbations of COPD. METHODS: A total of 380 COPD patients were recruited from 16 hospitals in Korea from June 2005 to April 2012 for analysis. We searched for independent predictors of frequent exacerbators in comparison with non-exacerbators. RESULTS: As the severity of emphysema increased, forced expiratory volume in 1 s (FEV1), and FEV1/FVC (forced volume capacity) worsened; hyperinflationary features characterised by higher total lung capacity (TLC) were observed (P < 0.05). Frequent exacerbators had lower body mass index (BMI), higher St George's Respiratory Questionnaire (SGRQ) scores, higher residual volume (RV)/TLC, more severe airflow limitation (lower FEV1 and FEV1/FVC), lower carbon monoxide diffusion capacity, lower serum protein levels and a higher emphysema index than non-exacerbators (P < 0.05). In multivariate analysis, frequent exacerbators were independently associated with a higher emphysema index, lower serum protein levels and higher RV/TLC (P < 0.05). CONCLUSION: Our data show that the severity of emphysema, severe static hyperinflation and serum lower protein levels are independent predictors of frequent exacerbations in COPD patients.

Ethnic diversity deflates price bubbles.

Markets are central to modern society, so their failures can be devastating. Here, we examine a prominent failure: price bubbles. Bubbles emerge when traders err collectively in pricing, causing misfit between market prices and the true values of assets. The causes of such collective errors remain elusive. We propose that bubbles are affected by ethnic homogeneity in the market and can be thwarted by diversity. In homogenous markets, traders place undue confidence in the decisions of others. Less likely to scrutinize others' decisions, traders are more likely to accept prices that deviate from true values. To test this, we constructed experimental markets in Southeast Asia and North America, where participants traded stocks to earn money. We randomly assigned participants to ethnically homogeneous or diverse markets. We find a marked difference: Across markets and locations, market prices fit true values 58% better in diverse markets. The effect is similar across sites, despite sizeable differences in culture and ethnic composition. Specifically, in homogenous markets, overpricing is higher as traders are more likely to accept speculative prices. Their pricing errors are more correlated than in diverse markets. In addition, when bubbles burst, homogenous markets crash more severely. The findings suggest that price bubbles arise not only from individual errors or financial conditions, but also from the social context of decision making. The evidence may inform public discussion on ethnic diversity: it may be beneficial not only for providing variety in perspectives and skills, but also because diversity facilitates friction that enhances deliberation and upends conformity.

Onset time of hyperkalaemia after angiotensin receptor blocker initiation: when should we start serum potassium monitoring?

WHAT IS KNOWN AND OBJECTIVE: Angiotensin receptor blockers (ARBs) frequently induce hyperkalaemia in high-risk patients. Early detection of hyperkalaemia can reduce the subsequent harmful effects. This study was performed to examine the onset time of hyperkalaemia after ARB therapy. METHODS: We carried out a retrospective analysis to determine the onset time of hyperkalaemia (serum potassium >5·5 mm) among hospitalized patients newly starting ARB therapy between 2004 and 2012, in a tertiary teaching hospital. Predefined possible risk factors and concomitant medications were evaluated. RESULTS AND DISCUSSION: During the 97-month study period, a total of 4267 hospitalized patients started ARBs as new drugs and 225 patients showed hyperkalaemia. A significantly increased risk of hyperkalaemia was detected among patients with a high baseline potassium [odds ratio (OR) 6·0] and those who took non-potassium-sparing diuretics (OR 2·2) or potassium supplements (OR 1·6). A high glomerular filtration rate (GFR) was associated with a lower risk of hyperkalaemia (OR 0·992). Fifty-two percentage of hyperkalaemic events occurred within the first week after initiation of ARB therapy. The highest frequency of hyperkalaemia occurred on the first day after initiation of ARBs. Hyperkalaemia occurred earlier in patients with a high baseline serum potassium level, reduced GFR, diabetes and in those without heart failure. WHAT IS NEW AND CONCLUSION: Hyperkalaemia occurs most frequently at the beginning of ARB therapy in hospitalized patients. Monitoring of serum potassium and estimated GFR after initiation of ARBs should be started within a few days or not later than 1 week, especially in patients with risk factors.

Unique features of non-obstructive emphysema and pure airway obstruction.

SETTING: Emphysema without airway obstruction or airway obstruction without emphysema are often detected clinically, although they are commonly co-existent. We therefore tested the hypothesis that non-obstructive emphysema and pure airway obstruction have unique features. METHODS: A case-control observation study was undertaken retrospectively in a patient cohort at a single centre. Among 2662 subjects who underwent chest computed tomography and pulmonary function tests, we enrolled 90 patients with non-obstructive emphysema, 119 with pure airway obstruction, 81 with obstructive emphysema and 2031 subjects as normal controls. The features of the four groups were analysed and compared. RESULTS: Higher serum homocysteine (13.4 ± 7.4 vs. 11.6 ± 4.6 mol/l), higher rate of osteoporosis (15.8% vs. 4.5%), higher leukocyte count, higher male ratio, lower serum albumin and lower body mass index were observed in subjects with non-obstructive emphysema than in controls (P < 0.05). In multiple logistic regression analysis of groups without airway obstruction, osteoporosis, hyperhomocysteinaemia, hypoalbuminaemia and higher leukocyte count were independent factors associated with non-obstructive emphysema (P < 0.05). CONCLUSION: Hyperhomocysteinaemia, hypoalbuminaemia, osteoporosis and higher leukocyte count were independent predictors of non-obstructive emphysema.

Risk factors of mortality among dengue patients admitted to a tertiary care setting in Kerala, India.

Dengue is one of the most serious and rapidly emerging tropical mosquito-borne diseases. The state of Kerala in India is hyperendemic for the disease and is one of the leading states in the reporting of deaths due to dengue. As primary prevention of dengue has had limited success, the prevention of mortality through the identification of risk factors and efficient patient management is of utmost importance. Hence, a record-based case control study was conducted in the Medical College Hospital in Thiruvananthapuram to identify the risk factors of mortality in patients admitted with dengue. Dengue patients over 40years of age were 9.3 times (95% CI; 1.9-44.4) more likely to die compared with younger patients. The clinical features associated with mortality from dengue were altered sensorium (odds ratio (OR) - 156, 95% CI; 12.575-1935.197), abnormal reflexes (OR - 8.5, 95% CI; 1.833-39.421) and edema (OR - 13.22, 95% CI; 2.651-65.951). Mortality was also higher in those patients with co-morbidities such as diabetes mellitus (OR - 26, 95% CI; 2.47-273.674) and hypertension (OR - 44, 95% CI; 6.23-315.499). The independent predictors of mortality were altered sensorium and hypertension. Dengue fever patients with these clinical features and those who are elderly should be more rigorously monitored and promptly referred from lower settings when required to reduce mortality.

Feasibility of intravenous flat panel detector CT angiography for intracranial arterial stenosis.

BACKGROUND AND PURPOSE: I.v. FDCT angiography is an emerging technology for the detection of intracranial vascular disease. This study was conducted to determine the feasibility of i.v. FDCT in estimating major atherosclerotic intracranial arterial stenosis with DSA as the reference. MATERIALS AND METHODS: DSA and i.v. FDCT were performed simultaneously in patients with transient ischemic attack or acute cerebral infarction. The degree and length of stenosis were measured. The stenotic vessels were categorized into 4 groups by the grade of stenosis: normal (<30%), mild (30%-49%), moderate (50%-69%), or severe (>70%). The vessels of the normal group were excluded from analysis to reduce spectrum bias. Measurement of vessels was recorded by using an electric ruler by a qualified endovascular neurosurgeon and a neuroradiologist. RESULTS: Eight hundred forty-two vessel segments in 69 patients were calculated. Mild (n = 56), moderate (n = 47) and severe stenosis (n = 46) groups were analyzed. I.v. FDCT had a sensitivity of 97.6%, specificity of 96.9%, and negative predictive value of 96.9% for detecting ≥50% stenosis and respective values of 91.9%, 98.2%, and 97.4% for depicting ≥70% stenosis. The difference of stenotic length between the 2 tests was not significant as an increase in the severity of stenosis (Spearman rank correlation test; r = -0.12, P = .13). CONCLUSIONS: I.v. FDCT can be a feasible alternative as a noninvasive method for evaluating stenosis of the major intracranial arteries.

Comparison of different techniques of cataract surgery in bacterial contamination of the anterior chamber in diabetic and non-diabetic population.

AIM: To compare the bacterial contamination of the anterior chamber (AC) between manual small incision cataract surgery (SICS) and phacoemulsification (Phaco). To study the conjunctival flora and bacterial contamination of AC between well-controlled diabetics and non-diabetics. MATERIALS AND METHODS: Three hundred and sixty-eight patients were randomized to manual SICS and Phaco. Sixty-eight patients were excluded for not completing follow-up or for intraoperative complications like posterior capsule rupture. One hundred and fifty patients in each group were finally analyzed. Conjunctival swabs were taken on admission, after one day of topical ofloxacin and 15 min after 5% Povidone Iodine (PI) instillation. AC aspirate at the end of the surgery was also cultured. RESULTS: Fifty-six (18.66%) patients had positive conjunctival swab on admission which was reduced to 19 (6.33%) with topical ofloxacin and to five (1.66%) with instillation of 5% PI. AC contamination in both manual SICS and Phaco was 0.66%. The conjunctival flora in diabetics was similar to non-diabetics. None of the diabetics had AC contamination. Statistical analysis was performed by Chi-Square test (with Yates' correction). CONCLUSION: Statistically significant reduction in conjunctival flora was achieved with topical ofloxacin and 5% PI instillation and AC contamination in both manual SICS and Phaco was minimal (0.66%). Well-controlled diabetics who underwent cataract surgery in this study had similar conjunctival flora and AC contamination as non-diabetics.

Different therapeutic responses in chronic obstructive pulmonary disease subgroups.

SETTING: Eleven referring hospitals in South Korea. OBJECTIVE: To compare therapeutic responses in chronic obstructive pulmonary disease (COPD) subgroups, classified by diffusing capacity of the lung for carbon monoxide (DL(CO)) and lung volume. DESIGN: A total of 130 stable male COPD patients were classified into four subgroups according to baseline DL(CO) and residual volume/total lung capacity (RV/TLC) ratio. We compared therapeutic responses to short acting ß(2)-agonist (SABA) and 3-month combined inhalation of long-acting ß(2)-agonist (LABA) and corticosteroid among patients with these subgroups. RESULTS: Among the 130 COPD patients, 41 (31.5%) had normal DL(CO) and RV/TLC, 28 (21.5%) low DL(CO) and normal RV/TLC, 31 (23.8%) normal DL(CO) and high RV/TLC, and 30 (23.1%) low DL(CO) and high RV/TLC. The normal DL(CO)/high RV/TLC subgroup showed a significantly larger flow response (changes in forced expiratory volume in 1 s) to salbutamol than the normal DL(CO)/RV/TLC subgroups, and a larger volume response (changes in forced vital capacity) than the two normal RV/TLC subgroups. The normal DL(CO)/high RV/TLC subgroup also showed significantly larger flow and volume response to 3-month combined inhalation of LABA and corticosteroid than the two normal RV/TLC subgroups. CONCLUSION: COPD subgroups classified by DL(CO) and RV/TLC may have different pulmonary function responses to pharmacological treatment.

Pulmonary artery pressure in chronic obstructive pulmonary disease without resting hypoxaemia.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) can lead to pulmonary hypertension and cor pulmonale, which are predictors of mortality. OBJECTIVE: To identify predictors of increased pulmonary artery pressure (PAP) in COPD patients without resting hypoxaemia, and to characterise COPD patients with increased PAP. DESIGN: A study of 117 COPD patients from the Korean Obstructive Lung Disease (KOLD) cohort who had measurable tricuspid regurgitant flow under transthoracic Doppler echocardiography and no resting hypoxaemia. RESULTS: The mean patient age was 67 years. Mean forced expiratory volume in 1 second (FEV(1)) was 47% predicted, mean haemoglobin (Hb) concentration was 145 g/l and mean systolic PAP (sPAP) was 33 mmHg. Multiple linear regression analysis showed that Hb was the only factor independently associated with sPAP (beta = -1.752, P = 0.005). Cluster analysis using FEV(1)% predicted, sPAP and Hb concentration as variables indicated three patient clusters: Cluster 1 (n = 36; mean FEV(1) 44% predicted, mean sPAP 39 mmHg, mean Hb 132 g/l), Cluster 2 (n = 45; FEV(1) 35% predicted, sPAP 31 mmHg, Hb 154 g/l), and Cluster 3 (n = 36; FEV(1) 65% predicted, sPAP 29 mmHg, Hb 148 g/l). CONCLUSION: Elevated PAP was linked to low haemoglobin levels in COPD without resting hypoxaemia.

Three phenotypes of obstructive lung disease in the elderly.

SETTING: Eleven referring hospitals in South Korea. OBJECTIVE: To classify the phenotypes in elderly subjects with obstructive lung disease (OLD). METHODS: We analysed 191 subjects aged ≥ 60 years with chronic respiratory symptoms and either obstructive spirometry or bronchial hyperresponsiveness. Factor analysis was performed using commonly measured variables and revealed four significant variables: 1) the ratio of inspiratory capacity to total lung capacity, 2) the total score on the St George's Respiratory Questionnaire, 3) the volume fraction of the lung less than 950 Hounsfield Unit at full inspiration on volumetric computed tomography and 4) post-bronchodilator forced expiratory volume in 1 second (FEV(1)) changes. We performed a cluster analysis on these four variables. RESULTS: The mean age was 68.5 (± 5.2 SD) years and the mean post-bronchodilator FEV(1) was 52.4% (± 16.5) predicted. Three clusters with the following phenotypes were identified: Cluster 1 included subjects with moderate to severe airflow obstruction and bronchodilator reversibility; Cluster 2 subjects had moderate airflow obstruction without bronchodilator reversibility, and Cluster 3 subjects had severe airflow obstruction without bronchodilator reversibility. CONCLUSIONS: We identified three phenotypes in elderly subjects with OLD. Follow-up studies are needed to explore the clinical significance of each phenotype.

Two-year follow-up of contrast stasis within the sac in unruptured aneurysm coil embolization: progressive thrombosis or enlargement?

BACKGROUND AND PURPOSE: The fate of contrast stasis within an aneurysmal sac after coiling has not been established. We followed and evaluated the potential risks of recanalization of unruptured aneurysms embolized with BPCs for 2 years. MATERIALS AND METHODS: A total of 301 unruptured aneurysms in 252 patients were treated with BPCs. Contrast stasis was observed on initial postembolization angiograms in 104 (34.6%) of these aneurysms. For follow-up, skull images by an angiographic unit (at 3, 9, 15, and 21 months), CE-MRA including TOF source images (at 6, 12, and 18 months), and DSA (at 24 months) were used. RESULTS: In 89 (85.6%) of the 104 aneurysms with contrast stasis, the stasis disappeared on 6-month MRAs and occlusions remained unchanged without recanalization for 2 years. In the remaining 15 (14.4%), recanalization occurred during follow-up. The presence of contrast stasis was not found to be associated with the obliteration rate (P = .641) or packing attenuation (aneurysms without contrast stasis 30.7% ± 11.18 versus aneurysms with contrast stasis 33.0% ± 12.11, P = .113). Contrast stasis was not found to be a risk factor for recanalization (15/104 [14.4%] versus 29/197 [14.7%], P = 1.000). CONCLUSIONS: Contrast stasis is a benign angiographic finding that can disappear within 6 months on follow-up MRA. In addition, contrast stasis was not found to be associated with a low obliteration rate or packing attenuation or to be a risk factor for recanalization. The present study shows that aneurysms with contrast stasis on initial postembolization angiograms are no more likely to recanalize than aneurysms without contrast stasis.

3D reconstructions of spinal segmental arteries using CT angiography: applications in minimally invasive spinal procedures.

BACKGROUND AND PURPOSE: Injury to spinal segmental arteries may potentially occur during spinal surgery, particularly during anterior or minimally invasive approaches. Use of a noninvasive radiologic tool to evaluate these arteries before surgery may reduce this risk. MATERIAL AND METHODS: We performed spinal CT angiography and reconstructed 3D images of segmental arteries in 41 patients. We classified the pathways and locations of the segmental arteries into 4 zones (A, B, C, and D) according to pedicle and vertebral endplates. We designated segmental arteries from T8 to L1 as "high-level segmental arteries" and those from L2 to L4, as "low-level segmental arteries." We compared the distribution of segmental arteries between these 2 groups. We also investigated anatomic variations of segmental arteries and the rate of occurrence of the artery of Adamkiewicz. RESULTS: In all patients, 3D reconstruction images from spinal CT angiography clearly showed the pathways of segmental arteries on the vertebral bodies. Most of the segmental arteries passed the middle portion of the vertebral body (zones B and C). However, 51 of 738 segmental arteries (6.9%) had uncommon pathways (zones A and D), and segmental arteries from L2 to L4 had a higher incidence of uncommon pathways than higher level vertebrae (P < .05). We also observed 2 types of segmental artery anatomic variation, agenesis and dual supply. CONCLUSIONS: We suggest that spinal CT angiography can help to precisely visualize the spinal segmental arteries and surrounding bony structures and can aid clinicians in deciding on optimal approaches for spinal surgery.