AIM To characterize and compare total lung capacity (TLC) measured by plethysmography with high-resolution computed tomography (HRCT), and to identify variables that predict the difference between the two modalities. METHODS Fifty-nine consecutive patients referred for the evaluation of COPD were retrospectively reviewed. Patients underwent full pulmonary function testing and HRCT within 3 mo...

BACKGROUND The study of body composition in specific populations by techniques such as bio-impedance analysis (BIA) requires validation based on standard reference methods. The aim of this study was to develop and cross-validate a predictive equation for bioelectrical impedance using air displacement plethysmography (ADP) as standard method to measure body composition in Mexican adult men and w...

BACKGROUND Impedance plethysmography applied to the head by using a pair of electrodes attached to the scalp surface is known as bipolar Rheoencephalography or REG I and was originally proposed to measure changes in cerebral blood volume related to the heartbeat. REG I was soon discarded in favor of other REG configurations, since most of the signal was shown to be heavily contaminated by the e...

Venography is the current standard for the diagnosis of deep vein thrombosis (DVT). Noninvasive tests have differing sensitivity and specificity, are technically demanding, and may be subject to variability in interpretation. Light reflection rheography (LRR) is a noninvasive method utilizing light-emitting diodes and a sensor to measure light reflected from the skin surface. The intensity of r...

This study was designed to test whether awareness of the measurement of breathing influences the breathing pattern in healthy subjects under routine laboratory conditions. Seventy four subjects (40 females and 34 males), aged 21-63 yrs, were studied under three different conditions whilst their breathing was being recorded for 5 min by means of inductance plethysmography (Respitrace): 1) subjec...

In asthma, airways constrict in response to emotion and stress, but underlying mechanisms, potential extrathoracic contributions, and associations with airway pathophysiology have not been elucidated. We therefore investigated the role of the cholinergic pathway in emotion-induced airway responses in patients with asthma and the association of these responses with airway pathophysiology. Patien...

BACKGROUND Ankle-brachial-Index (ABI) measured by manual Dopplersonography is an easily assessable marker of global cardiovascular risk. The aim of this study was to establish novel photo-plethysmography (PPG)-based ABI assessments in an epidemiologic context and to compare its results with those of Doppler. METHODS Two devices for PPG-based ABI assessments (Vicorder, Vascular Explorer) were ...