Using X-ray velocimetry to measure lung function and assess the efficacy of a pseudomonas aeruginosa bacteriophage therapy for cystic fibrosis.

Phase contrast x-ray imaging (PCXI) provides high-contrast images of weakly-attenuating structures like the lungs. PCXI, when paired with 4D X-ray Velocimetry (XV), can measure regional lung function and non-invasively assess the efficacy of emerging therapeutics. Bacteriophage therapy is an emerging antimicrobial treatment option for lung diseases such as cystic fibrosis (CF), particularly with increasing rates of multi-drug-resistant infections.

Mechanical ventilation decreases tidal volume heterogeneity but increases heterogeneity in end-expiratory volumes.

How the heterogeneous distribution of lung volumes changes in response to different mechanical ventilation (MV) strategies is unclear. Using our well-developed four-dimensional computed tomography (4DCT) high-resolution imaging technique, we aimed to assess the effect of different MV strategies on the distribution and heterogeneity of regional lung volumes. Healthy adult female BALB/c mice received either 2 h of "injurious" MV [ = 6, mechanical ventilation at high PIP with zero PEEP (HPZP)] with a peak inspiratory pressure (PIP) of 20 cmHO and zero positive end-expiratory pressure (PEEP), or 2 h of "protective" MV [ = 8, mechanical ventilation at low PIP with PEEP (LPP)] with PIP = 12 cmHO and PEEP = 2 cmHO.

The association between regional transcriptome profiles and lung volumes in response to mechanical ventilation and lung injury.

Background: Lung inhomogeneity plays a pivotal role in the development of ventilator-induced lung injury (VILI), particularly in the context of pre-existing lung injury. The mechanisms that underlie this interaction are poorly understood. We aimed to elucidate the regional transcriptomic response to mechanical ventilation (MV), with or without pre-existing lung injury, and link this to the regional lung volume response to MV.

The proteomic response is linked to regional lung volumes in ventilator-induced lung injury.

It is unclear how acid-induced lung injury alters the regional lung volume response to mechanical ventilation (MV) and how this impacts protein expression. Using a mouse model, we investigated the separate and combined effects of acid aspiration and MV on regional lung volumes and how these were associated with the proteome. Adult BALB/c mice were divided into four groups: intratracheal saline, intratracheal acid, saline/MV, or acid/MV.

Quantification of muco-obstructive lung disease variability in mice via laboratory X-ray velocimetry.

To effectively diagnose, monitor and treat respiratory disease clinicians should be able to accurately assess the spatial distribution of airflow across the fine structure of lung. This capability would enable any decline or improvement in health to be located and measured, allowing improved treatment options to be designed. Current lung function assessment methods have many limitations, including the inability to accurately localise the origin of global changes within the lung.

Real-time in vivo imaging of regional lung function in a mouse model of cystic fibrosis on a laboratory X-ray source.

Most measures of lung health independently characterise either global lung function or regional lung structure. The ability to measure airflow and lung function regionally would provide a more specific and physiologically focused means by which to assess and track lung disease in both pre-clinical and clinical settings. One approach for achieving regional lung function measurement is via phase contrast X-ray imaging (PCXI), which has been shown to provide highly sensitive, high-resolution images of the lungs and airways in small animals.

Interaction between regional lung volumes and ventilator-induced lung injury in the normal and endotoxemic lung.

Both overdistension and atelectasis contribute to lung injury and mortality during mechanical ventilation. It has been proposed that combinations of tidal volume and end-expiratory lung volume exist that minimize lung injury linked to mechanical ventilation. The aim of this study was to examine this at the regional level in the healthy and endotoxemic lung.

The Link between Regional Tidal Stretch and Lung Injury during Mechanical Ventilation.

The aim of this study was to assess the association between regional tidal volume (Vt), regional functional residual capacity (FRC), and the expression of genes linked with ventilator-induced lung injury. Two groups of BALB/c mice ( = 8 per group) were ventilated for 2 hours using a protective or injurious ventilation strategy, with free-breathing mice used as control animals. Regional Vt and FRC of the ventilated mice was determined by analysis of high-resolution four-dimensional computed tomographic images taken at baseline and after 2 hours of ventilation and corrected for the volume of the region (i.

Application of a novel in vivo imaging approach to measure pulmonary vascular responses in mice.

Noninvasive imaging of the murine pulmonary vasculature is challenging due to the small size of the animal, limits of resolution of the imaging technology, terminal nature of the procedure, or the need for intravenous contrast. We report the application of laboratory-based high-speed, high-resolution x-ray imaging, and image analysis to detect quantitative changes in the pulmonary vascular tree over time in the same animal without the need for intravenous contrast. Using this approach, we detected an increased number of vessels in the pulmonary vascular tree of animals after 30 min of recovery from a brief exposure to inspired gas with 10% oxygen plus 5% carbon dioxide (mean ± standard deviation: 2193 ± 382 at baseline vs.

High resolution propagation-based imaging system for in vivo dynamic computed tomography of lungs in small animals.

We have developed an x-ray imaging system for in vivo four-dimensional computed tomography (4DCT) of small animals for pre-clinical lung investigations. Our customized laboratory facility is capable of high resolution in vivo imaging at high frame rates. Characterization using phantoms demonstrate a spatial resolution of slightly below 50 μm at imaging rates of 30 Hz, and the ability to quantify material density differences of at least 3%.

Cardiogenic Airflow in the Lung Revealed Using Synchrotron-Based Dynamic Lung Imaging.

The beating heart is known to produce pressure and airflow oscillations in the lungs of mammals. This phenomenon is often disregarded as detailed measurement of its effects in the lung have hitherto not been possible. Previous studies have attempted to measure the effect of these oscillations on gas mixing.

Array-source X-ray velocimetry.

X-ray velocimetry (XV) has shown promise for investigations into various dynamic biological systems, including the motion of lungs and the flow of blood. Prior research in the field of XV has highlighted the need for both high spatial resolution to resolve features for tracking, and temporal resolution for accurate velocity measurement. In X-ray imaging systems, enhancement of spatial and temporal resolution requires a small focal spot size and high power output respectively, increasing anode power density requirements.

[Embolization of prostate arteries - an alternative technology for treatmetment of prostatic adenoma in patients with diabetes mellitus.].

The article details the examination plan and recommendations for the endovascular treatment of patients with prostate adenoma with concomitant diabetes mellitus. The results of the work of the Department of Andrology and Urology at the Endocrinological Research Center for prostate artery embolization are also displayed. A clinical case of care for a patient with prostate adenoma and severe diabetes mellitus is presented.

Technical Note: Contrast free angiography of the pulmonary vasculature in live mice using a laboratory x-ray source.

Purpose: In vivo imaging of the pulmonary vasculature in small animals is difficult yet highly desirable in order to allow study of the effects of a host of dynamic biological processes such as hypoxic pulmonary vasoconstriction. Here the authors present an approach for the quantification of changes in the vasculature.

Methods: A contrast free angiography technique is validated in silico through the use of computer-generated images and in vivo through microcomputed tomography (μCT) of live mice conducted using a laboratory-based x-ray source.

Quantification of heterogeneity in lung disease with image-based pulmonary function testing.

Computed tomography (CT) and spirometry are the mainstays of clinical pulmonary assessment. Spirometry is effort dependent and only provides a single global measure that is insensitive for regional disease, and as such, poor for capturing the early onset of lung disease, especially patchy disease such as cystic fibrosis lung disease. CT sensitively measures change in structure associated with advanced lung disease.

Imaging lung tissue oscillations using high-speed X-ray velocimetry.

This work utilized synchrotron imaging to achieve a regional assessment of the lung's response to imparted oscillations. The forced oscillation technique is increasingly being used in clinical and research settings for the measurement of lung function. During the forced oscillation technique, pressure oscillations are imparted to the lungs via the subjects' airway opening and the response is measured.

Correction of Retrograde Ejaculation in Patients with Diabetes Mellitus Using Endourethral Collagen Injection: Preliminary Results.

Introduction: Diabetic neuropathy secondary to diabetes mellitus type 1 (DM1) is responsible for retrograde ejaculation (RE) in 5-18% of cases. Medical treatment of RE is based either on increasing the sympathetic tone of the bladder or on decreasing the parasympathetic activity. However, the onset of side effects and the lack of response should be considered.

Prostatic Arterial Embolization vs Open Prostatectomy: A 1-Year Matched-pair Analysis of Functional Outcomes and Morbidities.

Objective: To evaluate 1-year surgical and functional results and morbidities of prostatic artery embolization (PAE) vs open prostatectomy (OP).

Patients And Methods: We undertook 1:1 matched-pair analysis (International Prostate Symptom Score [IPSS], peak flow [PF], postvoid residual [PVR], and prostate volume) of 287 consecutive patients treated for benign prostatic obstruction, including 80 OP and 80 PAE. Inclusion criteria were as follows: lower urinary tract symptoms or benign prostatic obstruction, IPSS ≥12, prostate-specific antigen (PSA) <4 ng/mL, or PSA between 4 and 10 ng/mL but negative prostate biopsy, total prostate volume >80 cm(3), and PF <15 mL/s.

Imaging regional lung function: a critical tool for developing inhaled antimicrobial therapies.

Alterations in regional lung function due to respiratory infection have a significant effect on the deposition of inhaled treatments. This has consequences for treatment effectiveness and hence recovery of lung function. In order to advance our understanding of respiratory infection and inhaled treatment delivery, we must develop imaging techniques that can provide regional functional measurements of the lung.

Prostatic artery embolization for prostate volume greater than 80 cm3: results from a single-center prospective study.

Objective: To investigate clinical benefits and safety of prostatic artery embolization (PAE) in patients with prostate volume ≥80 cm(3) and Charlson comorbidity index (CCI) ≥2 and affected by benign prostatic obstruction (BPO).

Patients And Methods: From January 2009 to January 2012, PAE was performed in 88 consecutive patients affected by clinical BPO. Inclusion criteria were symptomatic BPO refractory to medical treatment, International Prostate Symptom Score (IPSS) ≥12, total prostate volume (TPV) ≥80 cm(3), Qmax <15 mL/s, and CCI ≥2.

Functional lung imaging during HFV in preterm rabbits.

Although high frequency ventilation (HFV) is an effective mode of ventilation, there is limited information available in regard to lung dynamics during HFV. To improve the knowledge of lung function during HFV we have developed a novel lung imaging and analysis technique. The technique can determine complex lung motion information in vivo with a temporal resolution capable of observing HFV dynamics.

X-ray velocimetry within the ex vivo carotid artery.

X-ray velocimetry offers a non-invasive method by which blood flow, blood velocity and wall shear stress can be measured in arteries prone to atherosclerosis. Analytical tools for measuring haemodynamics in artificial arteries have previously been developed and here the first quantification of haemodynamics using X-ray velocimetry in a living mammalian artery under physiologically relevant conditions is demonstrated. Whole blood seeded with a clinically used ultrasound contrast agent was pumped with a steady flow through live carotid arterial tissue from a rat, which was kept alive in a physiological salt solution.

Synchrotron-based dynamic computed tomography of tissue motion for regional lung function measurement.

During breathing, lung inflation is a dynamic process involving a balance of mechanical factors, including trans-pulmonary pressure gradients, tissue compliance and airway resistance. Current techniques lack the capacity for dynamic measurement of ventilation in vivo at sufficient spatial and temporal resolution to allow the spatio-temporal patterns of ventilation to be precisely defined. As a result, little is known of the regional dynamics of lung inflation, in either health or disease.