by Dave King, a vascular technologist
Like many vascular technologists, I have worked in NHS and private hospitals and so have practical experience of dozens of different ultrasound machines to treat a variety of vascular and related diagnostic problems.
Some hospitals I dread because I know I’m going to have to use all my skills to get good results because the equipment is poor. This is both time consuming and mentally exhausting – and it doesn’t have to be like this.
The latest generation of ultrasound machines can run rings around some of the monsters of yesteryear.
However, even now, there are clear differences between machines, particularly when you need to work on ‘difficult’ patients.
Also while some machines are great at one type of investigation, they completely fail at another.
The difficult patient
All vascular technologists will know what I mean by ‘the difficult patient’.
They will be the friendliest, most cooperative patient you could hope for, but the problem is that they are obese.
Ultrasound doesn’t like obesity. It’s not just the depth the ultrasound has to penetrate when doing an abdominal scan, it’s the intervening soft tissues, fluid and gas that defocus the ultrasound beam and throw away the useful returning echos.
Or the patient might be as skinny as a rake but, especially if they are a diabetic or a renal patient, calcium deposited in the arterial wall can totally obscure the blood flow through the artery.
Obesity, renal and diabetic complications are increasing year on year in my work and so challenges for vascular technologists are on the rise.
Smart technology to the rescue
Riding to our rescue is new, smart technology which can, to some extent, compensate for these problems.
For instance, clever software algorithms can compensate for ultrasound velocity variations in different types of tissue, allowing the ultrasound beam to remain focused through a fat tummy.
Clever frequency and spatial compounding can make a spotty, unclear image quite smooth, making it easier to steer a needle with ultrasound guidance where other systems have effectively ‘lost the needle in the haystack’.
New technology also means we can do much more than we could even a decade ago.
When a patient is complaining of a swollen calf, a doctor will usually request an ultrasound DVT investigation.
Today it takes no more than an additional 30 seconds to show that fluid collection (superficial lymphoedema ) is the real problem, thanks to the exquisite imaging of the dilated lymph network just beneath the skin surface.
Zonare Z.ONE Colour Duplex scanner
The Zonare Z.ONE Colour Duplex scanner employs all these smart enhancements and as a result excels where other systems sometimes fall short.
The other great advantage of this machine is that it is portable.
As a locum ultrasound technologist, I provide ultrasound services in NHS hospitals, private hospitals and GP clinics, in fact wherever my services are needed in the UK.
When appropriate equipment is unavailable or the scanning room is already fully booked, I have the luxury of being able to detach the Zonare engine from its cart, grab a probe or two and go.
I know that this diminutive ensemble of equipment can match or exceed the performance of any of the big machines.
It also prevents patients having to be moved from the ward to the scanning room – something our profession hates because invariably the bed is wide, the room is too small and we end up straining our back and arm muscles to position the ultrasound probe in the optimum location on the patient’s neck.
A quick and easy alternative is to grab the Zonare engine with the probe plugged in ready to go, spare hot swap battery in my pocket, run up the stairs to the ward, place the engine on the patient’s bedside table, do the scan, get back to the scan room and report the results.
All this is quicker than waiting for the porters to negotiate the bed into the lift, through multiple doorways down to the scanning room where we have had to rearrange the furniture to squeeze the bed into a room which is not designed for the job.
I just love the concept behind the Zonare Duplex machine – I use all its capabilities in my research and everyday scanning work. Long live portable ultrasound, smart machines and clever software.
About Dave King
Dave King is a clinical vascular scientist/ bioengineer/inventor with 43 years experience in vascular ultrasound. Involved in the research group in Guy’s Hospital, London which inaugurated arguably the first vascular laboratory in the UK in 1968, Dr King currently has a research interest in failing dialysis fistulae AVF and has developed with his research team an ultrasonic blood pressure transducer UBPT which may assist early detection of fistula problems.
