Over the last decade the use of musculoskeletal ultrasound has increased dramatically. Physicians are now armed with a tool that allows them to perform diagnostic ultrasound evaluations of the musculoskeletal system and also track needle progress during a guided injection. During sports medicine fellowship, there is a large and expanding focus on ultrasound and the expectation upon graduation is to be proficient enough to use your skills out in practice. The reality is, ultrasound machines remain cost prohibitive and require a large capital investment from a healthcare institution in order to purchase one. This can be a frustrating time for a junior attending as they are anxious to deploy the skills they mastered during fellowship, but instead are spending time convincing administrators to pay for an ultrasound. This is where the Butterfly ultrasound can become a game changer. Not just for physicians in practice, but also those in training. Built from the ideas of CEO Dr. Jonathan Rothberg, the Butterfly ultrasound was created in Guilford, Connecticut.
A standard ultrasound probe uses quartz crystal transducers to create the image (Lurye, 2018). The Butterfly created an ultrasound probe made up of their newly developed synthetic chip composed of 9,000 metal transducers (Lurye, 2018). The probe currently only works with Apple compatible devices. I found the image to be clearer on the smaller iPhone screen verse the larger screen on an iPad. The probe is slightly heavier than other ultrasound probes and weighs in at 0.69lbs (Butterfly Network, 2019). The battery lasts for 2 hours between charges and the device comes with a charging station (Butterfly Network, 2019).
The Butterfly shows up in a single small box similar to a new iPhone. Outside of downloading the Butterfly Inc app, there is no other installation required. All you need to do is plug the ultrasound into your iPhone and you can start scanning. If you want to change from musculoskeletal imaging to soft tissue imaging, it is as easy as scrolling through the presets on the app screen. In seconds, I was flipping from cardiac mode to musculoskeletal mode to doppler mode. Images are also easily saved with a single click on the screen of the phone. One unique feature that highlights the advantage of having the probe plug into an iPhone involves adjusting the gain of an image. You can adjust the gain by swiping your finger from side to side over the portion of the image you would like to lighten or darken. This really helps highlight the structures you are trying to identify during a scan.
For this review of the Butterfly iQ, I evaluated the Butterfly’s use in sideline coverage, clinic, and for ultrasound guided injections.
The first area I evaluated the Butterfly in was for sideline use. For providers who have large computer-based ultrasounds in the office, these devices typically lack the required mobility for sideline use. The Butterfly offers an easy sideline solution. Its versatility as a single probe that acts as a linear, curved, and hockey stick probe make travelling with the ultrasound easy. One area of sideline coverage I am sometimes uncomfortable with is posterior back hits and the concern for renal laceration. Using the abdominal probe setting, I was quickly able to visualize the kidney. I was impressed with the detail of the kidney and I was able to switch over to doppler mode and view the arterial blood supply to the kidney.
I was also able to evaluate to perform a brief lung exam as well. It is easy to visual the pleura line and also to evaluate for B-lines which suggest pulmonary edema or lack of lung sliding suggesting pneumothorax.
As mentioned earlier, the price tag of the Butterfly make it a great entry level ultrasound for a provider just starting a clinical sports practice. When performing a diagnostic rotator cuff evaluation in clinic with the Butterfly, I was able to visualize all four rotator cuff muscles easily. I felt like there was more anisotropy during the evaluation, which led to more work to get a cleaner image. I was still able to visualize tendon insertion, but it did have less detail compared to other ultrasound machines. It performed better when visualizing superficial tendons, like the quadriceps tendon.
However, what made the Butterfly stand out was its easy ability to go from a soft tissue ultrasound to an echocardiogram. For primary care sports doctors, our practice may not be exclusively musculoskeletal issues. Depending on your primary training, you may also be managing medical patients in the clinic or emergency department. This probe gives us the flexibility to quickly obtain a four-chamber view of the heart in order to aid us in our diagnosis.
I was most excited to see how well the Butterfly would perform in ultrasound guided injections, as it could be a great tool for current fellows and new grads. After going through some of the more common injections, I would rate the Butterfly as a good entry level device. Visualizing the suprapatellar recess for a knee joint injection was very simple and gave a clear image.
This is in contrast to a hip joint injection, which did require more work on probe maneuvering to get a clear image of the femoral head and neck. I was still able to visualize the hip joint capsule and in the hands of an experienced provider, a hip injection can be performed easily.
Visualizing nerves was also more challenging with the Butterfly. While evaluating the median nerve within the carpal tunnel, I struggled with some of the detail of the superficial structures.
Some other structures that imaged well for ultrasound guided injections were the adductor tendons, biceps tendon sheath, and lateral epicondyle origin.
The handheld market for ultrasound continues to grow as more physicians discover the field known as POCUS (point of care ultrasound). One device most frequently compared to the Butterfly iQ is the Philips Lumify. The Philips Lumify platform uses Android devices and involves rental or purchasing plans for individual probes. One probe costs $199 per month and an additional $199 for any additional probe.
The Clarion is another alternative in the handheld ultrasound market. Again, you have to purchase a single probe and there are no package deals available. A single probe runs in the $15,000 price field for an outright purchase. The Butterfly iQ costs $1,999 and requires an annual subscription of $420 (Butterfly Network, 2019).
Ultimately, the Butterfly ultrasound offers physicians with an affordable and high-quality ultrasound to begin performing diagnostic evaluations and ultrasound guided injections. The price tag and versatility of the single probe really puts the Butterfly at an advantage over its competitors.
1. (2019, March). Retrieved from Butterfly Network: https://www.butterflynetwork.com/specs
2. Lurye, R. (2018, April 15). Starting With Ultrasound, an Innovation Empire is Growing in Guilford. Retrieved from Hartford Courant: https://www.courant.com/business/hc-biz-guilford-butterfly-network-rothberg-20180412-story.html