This at home ultrasound machine is just an amazing piece of technology, and I think one, which could change health care across the world. An Israeli company, Pulsenmore has developed a home ultrasound machine attachment that works with a smart phone. The main application allows pregnant women to take their own ultrasound scans and have them reviewed by their Obstetrician.
The system was started by an Israeli Obstetrician who has used it for 2000 of his patients. He gives the women guidance over the phone on scanning technique and then provides follow up care appointments throughout the term of the pregnancy.
The machine has received FDA approval in the USA so it's not unlikely that the equipment will be approved for use in Canada at some time. I discussed this with my wife who is a retired Cardiac and Ob/Gyn Ultrasonographer and she agrees that It's clear that this could be used for a lot more than self home health diagnosis of pregnancies. It puts the whole ultrasound baby pictures business into the realm of family photo taking and with the cooperation of physicians allows the guided diagnosis of all sorts of soft tissue medical issues.
Another interesting development in the at home ultrasound machine involves using a 3D augmented reality headset to do remotes ultrasound scans. David Black, a University of British Columbia PhD specializing in in medical robotics and imaging, mixed reality, and teleoperation in Canada has developed this system.
To operate the system, a nurse, or any health care worker without ultrasound training uses an existing ultrasound machine probe is connected to a device that allows 3D audio and visual feedback through the 3D goggles. The device is connected through the internet to a specialized hospital radiology department ultrasound machine.
A trained ultrasonographer, or a radiologist, hundreds or even thousands of miles away can then use a probe simulator device to coach the person doing point of care to get accurate scans by matching the sonographers probe position shown in the 3D goggle's display. The Sonographer verifies using their own ultrasound display that the point of care person is getting good useable diagnostic images
Dr. Silvia Chang is a Professor in the Department of Radiology at UBC who is collaborating with David Black. She is also the head of Abdominal Imaging in the Department of Radiology at Victoria General Hospital in British Columbia, Canada.
Here Dr Chang discusses how a trained hospital sonographer could easily perform ultrasound scans thousands kilometers away of remotely by guiding the hand movements of a person providing point of care. The Care person only has to match their hand position with the Sonographers hand position superimposed by the 3D headset.
It's not just remote parts of British Columbia in Canada that experience no access to Ultrasounds. Recent events have revealed that the entire US state of Alabama has a critical shortage of Ob/Gyn doctors and because of that the US Government is funding millions of dollars in remote or "robotic" ultrasounds, which in turn get sent digitally out of State to large hospitals.
Here is Dr Mehmet Oz talking about the program:
This has caused a controversy with Ob/Gyn specialist groups nationally, presumably because they would prefer the US federal government money being made available to hire more doctors to service Alabama.
More background on why Alabama has so few doctors and hospitals can be found here.
The piezoelectric crystal array used in most ultrasound machine probes today has been around at least 50 years. It is a tried and true technology but it has limitations. Piezo crystals are basically glass and can be easily damaged if dropped, it has hundreds of individual wires connecting the crystals which can short out or break. Most importantly the traditional probe scans in a narrow slice and is dependent on the skill of the operator manipulating it so the scan cut produce an optimal image.
A company called Butterfly networks has developed a new form of ultrasound probe. The scanning array they have invented is a thin flexible film of capacitive elements rather than piezoelectric crystals. The interconnection wiring is all done much like the process used in an integrated circuit chip.
The biggest game changer though is that the scan can be electronically adjusted 20 degrees off axis to eliminate the need for complex hand manipulation by a skilled sonographer. This makes the device much easier for use by an emergency room physician for example. The doctors skill is still needed to be able to interpret what is being scanned, but the actual process of getting a great picture of what is going on has been made significantly easier
To look at what could be coming down the pipe for the future of ultrasound we can see this project which combines the modalities of ultrasound and photo-acoustics.
Researchers are using an array of ultrasound sensors much like that now done for 3D and 4D ultrasound but in this case while some sensors focus on traditional ultrasound pictures, New sensors in the system sense ultrasonic vibration in blood cells allowing a 3D picture that not only shows soft tissue structures but blood flow to and from them. This new process is called RUS-PAT.
A typical hospital based ultrasound machine is used for many types of diagnoses. It typically has multiple ultrasound probes each one made for a specific kind of examination. One of the reasons hospital based ultrasound machines are large is that they have to provide high supply voltages and currents to some of the probes to drive the piezoelectric crystals in the probes.
If you want to make an ultrasound probe and machine smaller one method involves building the machine specifically to analyze one area of the body. The detection of tumour growth in breast cancer is an area like that.
MIT PhD student Colin Marcus and former MIT Doctor Osman Goni Nayeem have been working on breast cancer tumour tracking since 2023 an have refined their own Breast cancer ultrasound device into a package not much bigger than a couple of smart phones.
The idea they have come up is to make it possible to take an image of a suspicious growth and track it over multiple weeks to see if it is changing shape or getting larger. Things that could mark the growth as an aggressive cancer.
They plan to keep miniaturizing the technology until it becomes as simple to use as a holter monitor the patient takes homes and wears for a period of time monitoring any changes in growths previously detected in a regular mammogram.
It is important to note there are limitations to how well this equipment can work. It is tempting to think that this device is just a natural progression in ultrasound technology where the same processing power of a hospital machine can be packed into a smaller package. However, Ultrasound does require skilled operation & interpretation on the part of the sonographer. Larger hospital machines are made so that the sonographer can adjust a wide variety of parameters to get the very best image.
There are many variables that need to be manipulated to produce a high quality ultrasound image such that any pathology can be clearly seen. In the absence of a skilled operator and with miniaturized equipment you have to depend on automated adjustments which may not give you a great image. It restricts the clinician from seeing all but the most obvious problems.
As well, there is the durability of the equipment. The piezoelectric crystal array used in the probe end of the ultrasound machine is notoriously fragile. There are typically hundreds of crystals inside the probe connected by hundreds of fine wires that can easily be damaged.
Ultrasound machine probes are usually the most expensive part of any ultrasound machine. If you have a tiny machine where the ultrasound probe is built into the smartphone holder, you have no option but to replace the whole device if it gets dropped or the probe damaged.
There is also patient safety. Ultrasound machines heat up the body tissue that is being scanned. That's the primary reason doctors reccomend not having too many ultrasounds. System power is therefore another variable that has to be juggled to get deep enough penetration without exceding safety guidelines with respect to heat buildup.
Despite the inherent drawbacks there's got to be plenty more application for this device than simply obstetrics. Their are applications in wellness and disease prevention. General Practitioner's and Nurse Practitioners could use the device just like they use their stethoscope and blood pressure cuff right now. A recent article discusses how carotid artery ultrasound could be part of routine examination.
Links:
Jan 06/2025 - Wearable at home ultrasound machine replaces blood pressure cuff
The enduring drawback of modern Ultrasound comes from how it represents living tissue in 256 shades of grey. Doctors and Ultrasonographers all agree it would be much better if organs and tissue could be represented in colour.
Researchers are pioneering a new field called rotational ultrasound tomography (RUST) which involves combining two existing technologies and coming up with a system that enhances ultrasound images called RUST-PAT.
Photoacoustic Tomography (PAT) involves shooting a laser into soft tissue so that blood vessels and the fluids flowing through them vibrate at ultrasonic frequencies. Then, by using a highly modified 4D Ultrasound probe using a rotating sector scanner its possible to see not only the bladder, liver or kidney but all the vessels running through it. The vessels being highlighted in colour so it becomes easy to see the extent to which tumours have grown and are affecting nearby tissue