Chronic thromboembolic pulmonary hypertension is associated with a loss of total lung volume on computed tomography

BACKGROUND Although lung volumes are usually normal in individuals with chronic thromboembolic pulmonary hypertension(CTEPH),approximately 20%-29%of patients exhibit a restrictive pattern on pulmonary function testing.AIM To quantify longitudinal changes in lung volume and cardiac cross-sectional area(CSA)in patients with CTEPH.METHODS In a retrospective cohort study of patients seen in our hospital between January 2012 and December 2019,we evaluated 15 patients with CTEPH who had chest computed tomography(CT)performed at baseline and after at least 6 mo of therapy.We matched the CTEPH cohort with 45 control patients by age,sex,and observation period.CT-based lung volumes and maximum cardiac CSAs were measured and compared using the Wilcoxon signed-rank test and the Mann-Whitney u test.RESULTS Total,right lung,and right lower lobe volumes were significantly reduced in the CTEPH cohort at follow-up vs baseline(total,P=0.004;right lung,P=0.003;right lower lobe;P=0.01).In the CTEPH group,the reduction in lung volume and cardiac CSA was significantly greater than the corresponding changes in the control group(total,P=0.01;right lung,P=0.007;right lower lobe,P=0.01;CSA,P=0.0002).There was a negative correlation between lung volume change and cardiac CSA change in the control group but not in the CTEPH cohort.CONCLUSION After at least 6 mo of treatment,CT showed an unexpected loss of total lung volume in patients with CTEPH that may reflect continued parenchymal remodeling.

Spontaneous pneumomediastinum and Macklin effect:Overview and appearance on computed tomography

Spontaneous pneumomediastinum(SPM) is described as free air or gas located within the mediastinum that is not associated with any noticeable cause such as chest trauma.SPM has been associated with many conditions and triggers,including bronchial asthma,diabetic ketoacidosis,forceful straining during exercise,inhalation of drugs,as well as other activities associated with the Valsalva maneuver.The Macklin effect appears on thoracic computed tomography(CT) as linear collections of air contiguous to the bronchovascular sheaths.With the recent availability of multidetector-row CT,the Macklin effect has been seen in the clinical setting more frequently than expected.The aim of this review article is to describe the CT imaging spectrum of the Macklin effect in patients with SPM,focusing on the common appearance of the Macklin effect,pneumorrhachis,and persistent SPM with pneumatocele.

Adrenal Venous Sampling in Patients with Primary Aldosteronism: Which Is the Best Evaluation Method for Laterality Assessments?

Purpose: The purpose was to investigate the most accurate method of adrenal venous sampling to diagnose unilateral primary aldosteronism (PA) prior to laterality assessment. Materials and Methods: Sixty-four consecutive PA patients were enrolled in this retrospective study. A catheter was placed in the common-trunk-vein (CTV), below the confluence of the inferior-phrenic-vein and the central-adrenal-vein (CAV) and the right-adrenal-vein (RAV). Blood-sampling was performed both pre- and post-adrenocorticotropic hormone stimulation. Lateralized ratio [LR;aldosterone/cortisol ratio (ACR) on high-value side/ACR on low-value side], contralateral ratio (CR;ACR on low-value side/ACR on inferior-vena-cava ratio), and plasma aldosterone concentration (PAC) were evaluated. The diagnostic accuracy of LR, CR and PAC in CTV/ CAV/RAV during pre- and post-ACTH was compared by receiver-operating-characteristic (ROC) analysis. Results: LR-CAV post-ACTH showed the highest detection rate for unilateral adrenal lesions (93.3%;14/15), with a sensitivity of 0.93 and a specificity of 0.84 at a cut-off value of 2.5. CR-post-ACTH had the highest Az value (0.89), with a detection rate of 86.7% (13/14), a sensitivity of 0.98, and a specificity of 0.88 at a cut-off value of 0.8. Conclusion: CR-post-ACTH and LR-CAV-post-ACTH are accurate predictors for laterality assessment in PA.