The goal of this study is to find the best techniques to take non-invasive images of the arteriovenous fistula (AVF) in hemodialysis patients.

The vascular access is at the same time both the 'lifeline' and the 'Achilles' heel' of hemodialysis patients. Despite improved understanding of the pathophysiology of stenosis and thrombosis of the vascular access, unfortunately translating these advances into either improved therapies or a superior process of care has not been very successful. As a result, there continues to be an epidemic of arteriovenous fistula (AVF) maturation failure, a proliferation of relatively ineffective interventions such as angioplasty and stent placement, an extremely high incidence of catheter use (1).

A major problem is the timely diagnosis of AVF access dysfunction, which - undiagnosed and untreated - will eventually result in its loss. Current methods of diagnosing impending AVF deterioration utilize measurement of access flow, access flow recirculation, ultrasound imaging and angiography. None of these methods are applicable on a per-treatment basis and require some sort of intervention.

Recent advances in video-imaging open the opportunity to non-invasively track AVF movements, possibly on a routine basis. These AVF movements are created by the arterial pulse and routinely checked manually prior to each AVF cannulation. In this research the investigators plan to film the actual AVF movements with the goal to explore the technical feasibility of video-imaging based access surveillance.

Inclusion Criteria:

• age > 18 years; routinely cannulated AVF in place

Exclusion Criteria:

• inability to communicate in English
• skin maladies which render meaningful AVF imaging impossible
• vascular access procedures in the last 8 weeks

The investigators would like to study patients with chronic kidney disease, currently undergoing hemodialysis via AVF at Renal Research Institute dialysis clinics.