Pulmonary vascular morphology as an imaging biomarker in chronic thromboembolic pulmonary hypertension.

Patients with chronic thromboembolic pulmonary hypertension (CTEPH) have morphologic changes to the pulmonary vasculature. These include pruning of the distal vessels, dilation of the proximal vessels, and increased vascular tortuosity. Advances in image processing and computer vision enable objective detection and quantification of these processes in clinically acquired computed tomographic (CT) scans. Three-dimensional reconstructions of the pulmonary vasculature were created from the CT angiograms of 18 patients with CTEPH diagnosed using imaging and hemodynamics as well as 15 control patients referred to our Dyspnea Clinic and found to have no evidence of pulmonary vascular disease. Compared to controls, CTEPH patients exhibited greater pruning of the distal vasculature (median density of small-vessel volume: 2.7 [interquartile range (IQR): 2.5-3.0] vs. 3.2 [3.0-3.8]; P = 0.008), greater dilation of proximal arteries (median fraction of blood in large arteries: 0.35 [IQR: 0.30-0.41] vs. 0.23 [0.21-0.31]; P = 0.0005), and increased tortuosity in the pulmonary arterial tree (median: 4.92% [IQR: 4.85%-5.21%] vs. 4.63% [4.39%-4.92%]; P = 0.004). CTEPH was not associated with dilation of proximal veins or increased tortuosity in the venous system. Distal pruning of the vasculature was correlated with the cardiac index (R = 0.51, P = 0.04). Quantitative models derived from CT scans can be used to measure changes in vascular morphology previously described subjectively in CTEPH. These measurements are also correlated with invasive metrics of pulmonary hemodynamics, suggesting that they may be used to assess disease severity. Further work in a larger cohort may enable the use of such measures as a biomarker for diagnostic, phenotyping, and prognostic purposes.

Return to work and productive activities following a spinal cord injury: the role of income and insurance.

STUDY DESIGN: We analyzed longitudinal data on secondary outcomes from participants in a telerehabilitation study. OBJECTIVES: To examine the factors affecting return to productive activities and employment and the time to these events following a spinal cord injury (SCI). SETTING: A large southeastern rehabilitation hospital in the United States. METHODS: We used hazard regression models to analyze data from newly injured people (n=111) participating in an educational intervention post discharge who were followed for up to 2 years. Outcomes were time to return to productive activities and employment. RESULTS: Increasing age and being on Medicaid significantly decreased the likelihood of returning to productive activities (P<0.01), while being white (P<0.05) and having a higher median income (P<0.001) significantly increased this probability. The same factors, bar being on Medicaid, affected the return to employment. Whites returned to productive activities 2.5 times sooner than African Americans and employment twice as fast (P<0.001). Being in the 75th income percentile compared with the 25th shortened time to employment by 209 days. CONCLUSION: Findings here suggest that income and race affect the time to return to productivity and employment, while being on Medicaid also has a role in general post injury productivity.

Comparison of physiological and radiological screening for lung volume reduction surgery.

Physiological and radiological criteria are both used to identify candidates for LVRS. This study compares the predictive value of these screening techniques among patients with homogeneous (Ho) and heterogeneous (He) emphysema. Preoperative inspiratory lung conductance (G(Li)) during spontaneous breathing and quantitative radioisotope V/Q scan (QVQS) results were available for 48 of 50 patients undergoing bilateral LVRS for emphysema. Ho disease (n = 21) was defined by QVQS as an upper/lower perfusion ratio (ULPR) between 0.75 and1.25. G(Li) correlated with 6-mo improvement in FEV(1) (DeltaFEV(1)-6) (r = 0.53, p < 0.001) for the entire cohort, and for patients with both Ho (n = 21, r = 0.56, p = 0.015) and He disease (n = 27, r = 0.46, p = 0.017). ULPR correlated less well with DeltaFEV(1)-6 (n = 48, r = -0.38; p = 0.008) for the cohort, and was significantly correlated with outcomes only in the subgroup of patients with He disease (r = -0.40, p = 0.04). Multivariate regression demonstrated that by combining G(Li) and ULPR criteria, 33% of the DeltaFEV(1)-6 response could be accounted for. We conclude that both physiological and radiological criteria help identify appropriate candidates for LVRS. G(Li) best identifies patients with Ho emphysema who may benefit from surgery, but would be excluded on the basis of strictly radiological criteria. ULPR helps identify patients with He disease that improves with surgery, despite unfavorable G(Li).

Preoperative screening for lung volume reduction surgery: usefulness of combining thin-section CT with physiologic assessment.

OBJECTIVE: This study was performed to assess the usefulness of preoperative thin-section CT alone and in combination with physiologic measurements in emphysema patients being evaluated for lung volume reduction surgery. SUBJECTS AND METHODS: Six 1-mm collimation sections through the chest were obtained in 20 patients being evaluated for lung volume reduction surgery. Extent and severity of emphysema were assessed by visually scoring the images. CT scores ranged from 0 to 144. Inspiratory resistance was measured in 12 of 20 patients and was also used to discriminate between responders (change in forced expiratory volume in 1 sec, > or = 150 ml after surgery) and nonresponders (change in forced expiratory volume in 1 sec, < 150 ml after surgery). RESULTS: Four of 20 patients with mild emphysema as revealed by thin-section CT (scores of < 50) did not improve lung function after lung volume reduction surgery. Eight of the remaining 16 patients with moderate to severe emphysema as revealed by thin-section CT (scores of > 50) underwent inspiratory resistance measurement. Those seven patients whose inspiratory resistance measurement exceeded 8.5 cm H2O/l per second did not respond favorably to lung volume reduction surgery (change in forced expiratory volume in 1 sec, < 150 ml). The remaining five patients whose inspiratory resistance measurement was less than 8.5 cm H2O/l per second responded favorably to lung volume reduction surgery. Thus, only five of the 20 patients showed improvement in forced expiratory volume in 1 sec after surgery. CONCLUSION: Our data suggest that among patients with moderate to severe emphysema who are being examined for lung volume reduction surgery, the combination of radiologic and physiologic assessment is more accurate for predicting a favorable response to lung volume reduction surgery than radiologic assessment alone. However, in patients with chronic obstructive pulmonary disease by the American Thoracic Society criteria, mild emphysema as revealed on thin-section CT virtually precludes further workup because these patients are unlikely to respond favorably to lung volume reduction surgery.

Sarcoidlike reaction in patients with malignancy.

PURPOSE: To determine the radiologic features, pathogenesis, and prognostic importance of sarcoidlike reaction in patients with malignancy. MATERIALS AND METHODS: Radiographs and computed tomographic (CT) scans of the chests of 10 patients with known malignancy and either concurrent or subsequent development of noncaseating granulomas (NCG) were reviewed and correlated with histopathologic reports and pertinent clinical data. RESULTS: Ten patients with malignancy were found to have either mediastinal or hilar lymph node enlargement (n = 4) or parenchymal lung disease (n = 6). The presumptive diagnosis was metastatic disease. In eight of 10 histopathologic specimens, no tumor was found, but innumerable NCGs were present. They were thought to be consistent with sarcoidlike reaction. In the other two specimens, only a small focus of tumor cells was found amidst innumerable NCGs. On CT scans of the chests, parenchymal lung disease took the form of either ground-glass attenuation (n = 1) or nodules following perivascular and peribronchial distributions (n = 5). CONCLUSION: Lymph node enlargement and parenchymal lung nodules may not indicate metastatic disease. Sampling of all abnormal areas may be helpful in staging the disease and in treating and determining the prognosis of patients. Likewise, the discovery of NCG does not necessarily indicate sarcoidosis and may represent sarcoidlike reaction.

The effect of a contingent monetary reward on probation referrals to a drug abuse program.

Faced with reductions in public funds and calls for greater accountability, substance abuse programs can possibly increase revenues through patient fees by increasing referrals from the criminal justice system. Accountability can be improved through the use of organizational behavior management techniques. This study demonstrates the utility of behavioral techniques to increase referrals and revenue in an outpatient drug abuse program. The rate of criminal justice referrals increased substantially when counselors were offered "commissions" based on patient fees. These results are discussed with respect to the practicality of behavioral techniques in the management of drug abuse programs and with regard to policy implications.