Tuesday, February 3, 2015

Tryin’ To Make A Tricorder

Sometimes present technology stirs the imagination of a writer to think about what might come from it; progress for humanity, horrible nightmares, or further advances. And then there are the opposite cases, where something from a writer’s mind spurs a revolution in real world technology – the old, “We ought to be able to make one of those."

This is the first flight of the USS Enterprise. Actually, it
never went to space. Notice that the bottom of the shuttle
doesn’t have the thermal shield tiles, so it couldn’t
possibly go to space – well, at least it couldn’t come back.
Enterprise was scrapped for parts for subsequent shuttles.
Star Trek gave us both. The telephone could likely give rise to the communicator, and lasers probably influenced the idea of phasers. On the other hand, NASA honored Star Trek by naming the first of the space shuttles Enterprise, meaning that the fictional version predated the real version by some 10 years. But where did the tricorder idea come from?

The tricorder was a hand held monitoring device that could record and analyze data on a number of subjects. Spock used it to scan for life forms and geologic conditions, etc. Michael Jones, with Google, states that the tricorder’s mapping function was one of the inspirations behind Google Earth.

Scotty used it to analyze materials and warp cores. What was going on in the 1960’s that gave the idea to Gene Roddenberry that they could have a hand held device that would analyze just about anything?

McCoy’s medical tricorder was used for diagnosing the medical problems of the crew – except for the guy in the red shirt from the landing party – all he got was, “He’s dead Jim.” Bones also had a diagnostic bed that could be used in the sick bay. Sometimes on Next Generation they would use the tricorder while the patient was in the diagnostic bed. Apparently the patient wanted a second opinion.

Now we have an impetus to construct a real tricorder, at least the medical version. QualComm has put up the money for the Tricorder X Prize, worth a cool $10 million to the winning team in early 2016. This is just in time for the Star Trek 50th anniversary – on purpose or happy accident?

Here’s Bones with a tricorder from the original Star
Trek. I have found episodes with everyone using the
device, McCoy, Spock, Scotty, Sulu, Chekov, Kirk, even
Uhura. The gal in the back is Yeoman Rand, she used
the tricorder a lot in the eight episodes in which she
made an appearance.
A paper from 2006 provides a glimpse into the future. This study described a hand held gamma ray energy device for detecting cancer cells in a surgical setting. Remove the tumor and then probe to see if all the cancerous cells are gone from the site. I wonder if they re-purposed a salt-shaker for the probe.  This is a version of a tricorder function for diagnosis and to monitor treatment.

The current medical term for what a medical tricorder does is rapid medical assessment (RMA). RMA can be done by people as a method of triage in emergency departments, or by device as a diagnostic/treatment mechanism. A 2015 paper discusses the use of Mouthlab from Multisensor Diagnostics Company. This tool uses as disposable mouthpiece and a handheld device to monitor several vital signs (heart rate, temperature, respiratory rate, blood oxygenation) at once. This would then be a tricorder use for monitoring vitals and possibly biomarkers.

But the $10 million won’t come so easily; the hand held PET scanner did just one thing and the Mouthlab only does vital signs. To win the prize, the final tricorder must be able to diagnose at least 13 core health conditions (anemia, atrial fibrillation, chronic obstructive pulmonary disease (COPD), diabetes, Hepatitis A, leukocytosis, pneumonia, otitis media, sleep apnea, stroke, tuberculosis, urinary tract infection, as well as the absence of those conditions), as well as three elective conditions (allergens, cholesterol screen, food-borne illness, HIV screen, hypertension, hypothyroidism/hyperthyroidism, melanoma, mononucleosis, osteoporosis, Whooping Cough, shingles, or strep throat).

Think about it, those conditions include metabolic disorders, cancers, bacterial infections, viral infections, blood problems, cardiac electrical problems and bone density issues.

The name tricorder comes from the fact that it
recorded data and that it originally had three modes,
geologic, meterologic, and biologic. So it could be used
for many things. Here, Data uses it as a hand puppet
after he receives his emotion chip.
But it gets harder, the device must also be able to measure several vital signs and transmit the data for real time analysis and monitoring. Perhaps the toughest requirement? The entire instrument can’t weigh more than five pounds (2.26 kg)

The Star Trek medical tricorder didn’t touch your body, the salt shaker, er…..probe, was waved across your body and you looked at the old time tape recorder with the shoulder strap to see the results. We haven’t got there yet, at least not for all tests. Today, most tests still require some sample taken from the patient and then assessed in a laboratory for specific characteristics.

Changes from normal chemistry, or the presence or absence of some key molecule are then indications of certain disease states. Usually there is a list of possible diseases (a differential diagnosis) and then additional laboratory tests or diagnostic procedures (surgery, PET, MRI, etc) are used to eliminate some possibilities and strengthen others.

Some tests we currently have don’t require touching the patient or taking a sample, mostly imaging methods (X-ray, MRI, PET scan), but most laboratory tests require something given by a patient (saliva, urine) or taken from a patient (tissue, blood).

This is an old example of lab on a chip, although it is still
one of the prettiest. This chip was used for DNA
sequencing. Each channel had a final endpoint in which
the reaction took place and was then read.
The current methodology for performing many tests in a short time and a small space using a small sample is called “laboratory on a chip.” A small liquid sample is dispersed on a surface, into many wells or areas where specific tests can be performed. The whole thing may use less than a single drop of sample.

Microfluidics is a whole field of research that is used to inform the designers how to get small fluid samples to the areas and how small fluid volumes behave. It isn’t just the biochemical or molecular tests that are challenging, it’s getting the sample to the test areas. Once in the testing areas, then the chemistry can be run to produce products or measure components of the sample.

The tricorder devices will have to have a way to measure the results of the reactions or the properties of the fluid. How it gathers the data is important and takes a lot of technology. UV/Visible spectroscopy looks for the absorbance of light rays (colors or fluorescence); mass spectroscopy identifies molecules by mass to charge ratio.

On the other hand, Raman Spectroscopy measures the unique vibrational and rotational characteristics of specific molecules and ultra thin layer chromatography separates molecules based on solubility and mass. Each of these technologies usually requires desk-sized pieces of equipment; the winning device might use any or all of these measurement techniques.  This makes the weight requirement of five pound max a little tougher to achieve.

This is a schematic which shows UV or visible light
spectroscopy. With UV you can measure DNA, RNA, or
fluorescence With visible light, you can measure the
intensity of colors. Each can give information about
how much of a certain compound is there.

The sample components or reaction measurements will be made and their amounts will be assessed relative to the total sample. Those values, along with vital functions data will be assessed by the machine and a diagnosis will be rendered.

The goal is to have consumers use the product themselves, without need for medical professionals or extensive medical knowledge. Therefore, the workings of the machine must be self-contained and self-diagnosing, and the analysis must come down to specific, but easily understandable results. Not easy for a device that may use some very high tech mechanisms. Of course, there’s nothing saying that the finalists must use lab on a chip technology – it could be something completely new.

Good luck to all the ten finalists. You can learn about their projects here. Next week, we take a look at warp drive. Is it possible to use antimatter or plasma for travel? And what about that speed of light thing?

Contributed by Mark E. Lasbury, MS, MSEd, PhD

Fridman GY, Tang H, Feller-Kopman D, & Hong Y (2015). MouthLab: A Tricorder Concept Optimized for Rapid Medical Assessment. Annals of biomedical engineering PMID: 25605586

Chandler, D. (2014). A Doctor in the Palm of Your Hand: How the Qualcomm Tricorder X-Prize could help to revolutionize medical diagnosis IEEE Pulse, 5 (2), 50-54 DOI: 10.1109/MPUL.2013.2296803

Gulec SA, Daghighian F, & Essner R (2006). PET-Probe: Evaluation of Technical Performance and Clinical Utility of a Handheld High-Energy Gamma Probe in Oncologic Surgery. Annals of surgical oncology PMID: 16865592

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