Inspiratory and expiratory HRCT findings in Behçet's disease and correlation with pulmonary function tests

Does quantitative lung SPECT detect lung abnormalities earlier than lung function tests? Results of a pilot study

BACKGROUND

Heterogeneous ventilation in lungs of individuals with allergies, cigarette smokers, asthmatics and chronic obstructive pulmonary disease (COPD) patients has been demonstrated using imaging modalities such as positron emission tomography (PET), magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT). These individuals suffer from narrow and/or closed airways to various extents. By calculating regional heterogeneity in lung ventilation SPECT images as the coefficient of variation (CV) in small elements of the lung, heterogeneity maps and CV-density curves can be generated and used to quantitatively measure heterogeneity. This work explores the potential to use such measurements to detect mild ventilation heterogeneities in lung-healthy subjects.

METHOD

Fourteen healthy subjects without documented lung disease or respiratory symptoms, and two patients with documented airway disease, inhaled on average approximately 90 MBq (99m)Tc-Technegas immediately prior to the 20-min SPECT acquisition. Variation in activity uptake between subjects was compensated for in resulting CV values. The area under the compensated CV density curve (AUC), for CV values greater than a threshold value CVT, AUC(CV > CVT), was used as the measure of ventilation heterogeneity.

RESULTS

Patients with lung function abnormalities, according to lung function tests, generated higher AUC(CV > 20%) values compared to healthy subjects (p = 0.006). Strong linear correlations with the AUC(CV > 20%) values were found for age (p = 0.006) and height (p = 0.001). These demonstrated that ventilation heterogeneities increased with age and that they depend on lung size. Strong linear correlations were found for the lung function value related to indices of airway closure/air trapping, residual volume/total lung capacity (RV/TLC; p = 0.009), and diffusion capacity of the lung for carbon monoxide adjusted for haemoglobin concentration in the blood (DLCOc; p = 0.009), a value partly related to supposed ventilation/perfusion mismatch. These findings support the association between conventional lung function tests and the AUC(CV > 20%) value.

CONCLUSIONS

Among the healthy subjects, there is a group with increased AUC(CV > 20%) values, but with normal lung function tests, which implies that it might be possible to differentiate ventilation heterogeneities earlier in a disease process than by lung function tests.

Evaluation of Biventricular Myocardial Performance Index in Patients with Behçet's Disease

OBJECTIVE: The global function of both left ventricular (LV) and right ventricular (RV) functions were compared in patients with Behçet's disease (BD) versus healthy controls. METHODS: Biventricular function was evaluated by measurement of the myocardial performance index (MPI) evaluated from tissue Doppler echo-cardiographic measurements in 24 BD patients and was compared with measurements in 24 age- and sex-matched healthy controls. RESULTS: Significantly higher MPI values were associated with ventricular dysfunction. The study demonstrated impaired RV function in patients with BD compared with healthy controls, whereas normal LV function was observed both in patients with BD and in healthy controls. CONCLUSION: Early noninvasive evaluation of the properties of BD during the asymptomatic phase of this inflammatory disease may have prognostic value in the management of patients.

Pulmonary involvement in Behçet's disease

BACKGROUND

Behçet's disease (BD) is a multisystem vasculitis and pulmonary involvement in BD is reported to indicate poor prognosis and high mortality.

OBJECTIVES

The aims of this study were to report on patients with pulmonary involvement and to discuss pulmonary artery thrombus and small-sized vasculitis associated with BD, with respect to previously published cases.

METHODS

Fifteen patients with BD and pulmonary involvement were included in this study. Massive hemoptysis was observed in all patients having pulmonary artery aneurysm (PAA).

RESULTS

Eleven patients had macroscopic pulmonary vascular disease (2 PAA, 3 PAA and thrombi and 6 only thrombi) and 3 patients had microscopic pulmonary vascular disease. The remaining patient had pulmonary cryptococcosis.

CONCLUSIONS

Data regarding treatment and outcomes of patients having BD-related pulmonary emboli/infarct and small-sized vasculitis are limited. Pulmonary vasculitis affects different levels of the pulmonary artery in BD and should be classified as macroscopic and microscopic vascular disease. 'Pulmonary artery thrombosis' should be used instead of 'pulmonary emboli'. Spiral CT angiography is the best radiological tool for evaluation of pulmonary problems in BD. Treatment of vasculitis should be based on the type of vascular disease and may vary among different types of vascular disease. Anticoagulation can be used in patients with microscopic vascular disease and nonaneurysmal macroscopic vascular disease. More studies are needed to clarify this issue.