Using Smartphones as a Medical Device for Point-of-Care Applications
What makes smartphones as a medical device exciting as potential point of care platform?
Smartphones are the most widely used portable devices in the world today. According to Statita, the number of current worldwide smartphone users is around 3.5 billion. This means that 45% of the world’s population owns a smartphone. It is predicted that by 2023, the number of mobile device users will increase to 7.3 billion. Considering that smartphone manufacturers offer new models every year, the number of smartphones in circulation is likely three times that number or more.
The price of smartphones ranges from $50 USD for the most basic units to US$1500 for high-end branded units. Smartphones are ubiquitous, very affordable and have lots of powerful features which are perfect to support a variety of medical diagnostic applications at the point-of-care.
8 Reasons to use smartphones as a medical device for Point-of-Care applications
Easy-to-use and portable. Given the lucrative market and tight competition, manufacturers have employed the latest available technologies and design to create a user experience that satisfies consumer needs. Smartphones can be held in one hand and have very responsive touch screens. They have generally been drop tested and some models are water resistant. They are lightweight and can be comfortably carried for long periods of time. The batteries are very compact and can store enough energy for 1 to 3 days of usage without charging. These features align perfectly with the requirements of point-of-care devices for medical diagnostics. They should be portable, able to run tests for multiple patients in a day, and easy-to-use even for people who are not medical practitioners.
Connectivity. Smartphones are primarily designed to connect to other phones for people to communicate via voice or text messaging. Smartphones nowadays are typically equipped to use multiple connectivity standards. They are able to operate using GSM, 4G, LTE and 5G. They can connect to other systems using a wireless technology that allows monitoring devices to talk to each other (ANT+). They can access the global positioning system (GPS) and global navigation satellite system (GLONASS). Smartphones can also interface with USB, WIFI, Bluetooth and near-field communication (NFC). These connectivity features can be used to connect accessory parts of a medical diagnostic tool and to transmit data to a remote server or physician for review and diagnostic interpretation. GPS can be used to gather location data or monitor patients. For example, they could give data on where diagnostic tests were conducted in any part of the world, giving surveillance data that would be particularly useful during an epidemic.
Image capture and high-resolution video. The resolution of smartphone cameras is very impressive. Some smartphones are capable of capturing images with resolutions up to 64 Megapixels (MP) with multiple aperture settings (F1.8, F2.0, F2.2). They have auto focus features with hybrid optical zoom using the state-of-the-art lenses. Some models can record video up to UHD 8K (7680 x 4320) @ 24 FPS, slow motion at 960 fps@ HD (1280 x 720), and high-speed image capture at 240fps@FHD (1920 x 1080). The majority of the diagnostic platforms use optical systems. The ability of some smartphones to capture images at 64MP at low light conditions is suitable for fluorescence detection. With an added microscope lens, smartphones can detect fluorescence as analytes react to an assay. Cells and other microscopic materials can also be captured both as stills and in video mode. In terms of medical diagnostics, this may be the most useful feature that smartphones have.
High definition display. Smartphones support impressive high-definition displays. Even with their compact size, models are available with resolutions up to 4K, capable of displaying over 16 million colours. Numerous display technologies can be used including in-plane switching liquid-crystal displays (IPS LCD) and active-matrix organic light emitting diode displays (AMOLED). AMOLED displays can be viewed clearly even in a bright environment. This can be important in situations where the point-of-care may be in an environment where viewing an ordinary display tends to be difficult. In resource limited countries, mobile and portable clinics are very common and a display that can be viewed in the field is very important.
Embedded sensors. The sensors embedded in smartphones include accelerometers, barometers, finger print readers, gyroscopic sensors, geomagnetic sensors, hall effect sensors, RGB light sensors, proximity sensors, and more. Accelerometers and gyro sensors can be used to monitor the movement of patients (i.e. walking, movement while sleeping, or even in the event of a fall). Temperature and RGB light sensors are used for monitoring patients’ vital signs such as monitoring pulse, breathing and oxygen saturation levels.
Sound capture and audio output. The audio output of smartphone speakers is getting better and better. It is simple to connect smartphones to external audio output devices via Bluetooth or phone jack. Audio can be played in many formats such as MP3, WAV and M4A. Smartphones’ built-in microphones can capture sound around the device. Software applications could be written to output sound over a range of frequencies and volumes. Possible medical applications include assessing hearing loss, and therapies for tinnitus (for example Otoharmonics Levo system).
Software applications (APPS). Smartphones are typically updated regularly with the latest iOS or Android operating systems. The systems are bundled with a variety of software applications for running the smartphone’s functions, and various proprietary and third-party applications which are available to meet consumer’s needs. Developers can create their own apps. For medical diagnostics, these could take the form of graphical user interfaces (i.e. instrument control elements, graphs, charts), report generation tools, or cloud-based data management software. The ability to quickly develop and manage software applications for smartphones is another one of their key advantages.
Processing capability and memory. Modern smartphones have impressive computing power. Octa-core CPUs (8 processing units) with clock speeds >2 GHz are common. Random access memory (RAM) capacities can be as high as 12 GB, with internal storage (read-only memory – ROM) up to 128 Gigabytes (GB), and external storage up to 1 TB. These specifications are equivalent to six (6) desktop PCs from 10 years ago. That is a very impressive processing power in the palm of your hand! For medical device applications, this could be used for processing complex algorithms such as image analysis, machine learning (ML) and even artificial intelligence (AI) to predict correlations from a huge set of data.
Current smartphone medical diagnostic devices
Universities, research communities and start-up companies have started to incorporate smartphones into their products. The following are examples of companies that have produced medical devices using smartphones either as an included part of their product, or as a component to be provided by the end user, with their product being an accessory.
StethIO has designed and developed an elegant stethoscope using a smartphone. The StethIO hardware combines aesthetic design with a sound capture module to record and decompose sounds into their frequency components, constructing a spectrogram. Audio playback is synchronized with accurate visualization to assist in diagnosis.
StethIO analyzes the sound of the heart in real time and displays the sound frequencies
- CellScope
CellScope’s otoscope uses a smartphone camera for remote diagnosis of pediatric ear infections. The CellScope software application connects the digital otoscope and stores images for better diagnosis of ear health. Otoscope attached to Smartphone.
The AliveCor® KardiaMobile EKG Monitor is an FDA-Cleared wireless personal EKG that connects to a smartphone. It monitors heart activity and records the data on the phone. The portable EKG device is a single-lead electrocardiogram reader that is placed at the back of a smartphone. The EKG chart and other heart information is displayed via an app. The device could be used in intensive care units and by Emergency Medical Technicians (EMT).
AliveCor EKG attached to smartphone during the measurement
Due to its portability, the device can be used anytime and anywhere. A user can conduct a rapid assessment of cardiac problems, like atrial fibrillation, in the field. Using the device’s wireless capabilities, users can transmit any questionable EKG results to another smartphone or server for consultations with cardiologists from the field.
Butterfly iQ is a portable single probe ultrasound device that delivers a 2D array of 9000 micro-machined sensors connected to a smartphone. Butterfly’s Ultrasound-on-Chip™ technology replaces the older transducer system with many sensors on a single silicon chip. The device is designed with a built-in battery and wireless charging, which offers over two hours of scanning time. This portable ultrasound tool can help medical practitioners make better decisions at the point-of-care.
Butterfly iQ, a small ultrasound device connected to smartphone
- MobiUS
Mobisante, Inc. has received 510(k) clearance from the FDA for its smartphone-based ultrasound imaging system, MobiUS. The device is an innovative, portable, affordable and accessible ultrasound imaging system that uses a smartphone and internet cloud services.
The ParatusPerio® Test analyzes 5 bacteria, 2 cytokines (indicators of inflammation), and 1 proteinase (actual molecule that destroys tissue) to determine a patient’s oral health. The diagnostic tool includes a cartridge that attaches to a smartphone. The device uses the smartphone’s camera to capture an image of the assay reaction and analyses the result using an app.
The ParatusPerio® module attachment to Smartphone
Healthy.io transforms the smartphone camera into a clinical grade medical device by combining AI and machine learning (ML) for colorimetric analysis. The company’s first product is a smartphone-powered urinalysis device cleared by the FDA and European regulators as equivalent to lab-based testing.
Another application is in wound management. The company released a CE-marked and FDA-registered product for digitalized wound assessment. The device is used to support decisions for wound care and track healing over time.
FDA cleared Smartphone and the kit for urine test
Luminostics developed a diagnostic platform with smartphone readout for rapid home testing, point-of-care testing, and global health applications. The diagnostics platform is compatible with most smartphone models, can detect or measure bacteria, viruses, proteins, and hormones from swabs, saliva, urine, and blood.
The company’s core innovation is a new type of nanoparticle that is detectable using a smartphone’s built-in camera and flash in combination with the company’s proprietary hardware and software technology.
Luninostics diagnostic device using smartphone
How about smartphones as a medical device diagnostic tool at the point-of-care?
My answer is definitely yes! The powerful features of smartphones are perfectly suited for a medical diagnostic platform requiring optics, sound analysis, high-resolution display and software applications. In terms of availability, usability and portability, smartphones are well designed and very easy to use. They have the processing power of a laptop, tablet PC, iPad or even desktop computer. For medical diagnostic tools at the point-of-care, it is definitely possible to leverage some of these salient features. Potential diagnostic applications could include glucose monitoring, flow cytometry, rapid kits, medical diagnostics with microfluidic devices, digital health for monitoring hard-to-heal wounds, portable microscopes, monitoring vital signs and even for surveillance for chronic health conditions.
Takeaways
Smartphones as a medical device are here to stay (or until neuralink comes on-line in 15 years)! Innovation will continue to move these devices forward for consumer use. Currently, smartphone hardware is robust and dependable. Processing power, RAM and storage capacities are sufficient for many medical device applications. Many connectivity options are available, with more on the horizon (5G). Impressive integrated optical systems are standard, and displays will continue to adapt to the latest innovations.
While smartphones are generally used as consumer products, when combined with medical hardware attachments and software applications, they will be used more and more for medical applications. The trend towards decentralizing health care empowers individuals to do tests at the point-of-care – doctors’ clinics, mobile clinics or even in-home. With the COVID-19 pandemic, home tests and telemedicine are growing throughout the global health system.
Smartphones as a medical device will play a major role in the way healthcare providers handle diagnostics, monitoring and provision of the diagnosis at the point-of-care. If you would like to discuss how to use a smartphone in your next medical device, please contact us.
Lorenzo Gutierrez is the StarFish Medical Microfluidics Manager and Interim Toronto Site Director. Lorenzo has extensive experience translating point of care assays to microfluidic cartridges. His microfluidics portfolio includes developing a polyvalence instrument for early infant diagnostics at Chipcare.
Images: StarFish Medical