Related Experiment Video
Updated: Mar 2, 2026

Magnetic Resonance Imaging Quantification of Pulmonary Perfusion using Calibrated Arterial Spin Labeling
Published on: May 30, 2011
Perfusion by Arterial Spin labelling following Single dose Tadalafil In Small vessel disease (PASTIS): study protocol
Mathilde M H Pauls1,2,3, Natasha Clarke1,4, Sarah Trippier4
1Neurosciences Research Centre, Molecular and Clinical Sciences Research Institute, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK.
Background:
Cerebral small vessel disease is a common cause of vascular cognitive impairment in older people, with no licensed treatment. Cerebral blood flow is reduced in small vessel disease. Tadalafil is a widely prescribed phosphodiesterase-5 inhibitor that increases blood flow in other vascular territories. The aim of this trial is to test the hypothesis that tadalafil increases cerebral blood flow in older people with small vessel disease.
Methods/Design:
Perfusion by Arterial Spin labelling following Single dose Tadalafil In Small vessel disease (PASTIS) is a phase II randomised double-blind crossover trial. In two visits, 7-30 days apart, participants undergo arterial spin labelling to measure cerebral blood flow and a battery of cognitive tests, pre- and post-dosing with oral tadalafil (20 mg) or placebo.
Sample Size:
54 participants are required to detect a 15% increase in cerebral blood flow in subcortical white matter (p < 0.05, 90% power). Primary outcomes are cerebral blood flow in subcortical white matter and deep grey nuclei. Secondary outcomes are cortical grey matter cerebral blood flow and performance on cognitive tests (reaction time, information processing speed, digit span forwards and backwards, semantic fluency).
Discussion:
Recruitment started on 4th September 2015 and 36 participants have completed to date (19th April 2017). No serious adverse events have occurred. All participants have been recruited from one centre, St George's University Hospitals NHS Foundation Trust.
Trial Registration:
European Union Clinical Trials Register: EudraCT number 2015-001235-20 . Registered on 13 May 2015.
More Related Videos
13:48Reduction of Radiation Exposure during Endovascular Treatment of Peripheral Arterial Disease Combining Fiber Optic RealShape Technology and Intravascular Ultrasound
Published on: April 21, 2023
09:33A Methodological Approach to Non-invasive Assessments of Vascular Function and Morphology
Published on: February 7, 2015