What is telesurgery and how long has it been in development?
Telesurgery, or remote surgery, is the ability for a doctor to perform surgery on a patient even though they are not physically in the same location.
Telesurgery has been in existence for some time, but there have been substantial barriers to its implementation, including adequate bandwidth and delays in video feedback.
This type of surgical innovation has been of interest to the military and while it has already been tested between countries, the Florida Hospital Nicholson Center’s research is primarily focused on testing lag times across technology-rich locations, such as hospital campuses domestically.
Once the test has been successfully practiced across campuses in the US, we will move on to longer distances until we find the threshold where the system breaks down.
What are the main applications telesurgery would be beneficial for?
Telesurgery is beneficial for military as well as domestic purposes. Domestically, telesurgery eliminates the need for patients to travel thousands of miles for procedures, increasing access the best medical care.
How have advances in bandwidth technology impacted the feasibility of safe telesurgery?
Without advanced bandwidth capabilities, the Internet is not robust enough to perform telesurgery. We have to demonstrate that the Internet is reliable enough carry real-time data from the operating room in this manner.
Our research is showing that the bandwidth capabilities exist in the current structure of our hospitals and that doctors can safely handle a certain level of delay while performing surgery.
What impact can lag time effects have on surgeons during robotic surgery?
Lag time, or latency, is particularly important to measure for telesurgery because it impacts how safely a surgeon can operate with telesurgery, and it is where the bottleneck in the technology has traditionally existed.
If robotic surgeons are unable to compensate for lag times in telesurgery, it could potentially hinder the procedure and endanger the patient.
Once we fully understand where and when lag is not the limiting factor, we can move on to other societal issues that will need to be solved before real telesurgery can be offered to the public.
At what point do delays become undetectable to surgeons performing surgery?
During the latency test we conducted, it was determined that surgeons began to feel the lag at 300 milliseconds, and in the 300-500 milliseconds range, surgeons attempted to compensate for the feeling by slowing their movements and becoming more conscious about every step.
The surgeons’ movements at this level were no longer one fluid stroke, but a sequence of individual steps connected together. Beginning at 600 milliseconds, most surgeons could no longer handle the latencies and performed the tasks unsafely.
How can lag times be tested?
We first tested a large number of surgeons at different lag times between 100ms and 1,000 ms. We did this with a simulator because the real surgical robots are not currently capable of operating through the internet.
From this we identified 0 to 200 ms as a range where latency is not visible to surgeons, 300 to 500 ms as a range where most could compensate for the effect, and 600 ms and higher as a level that is unsafe.
Then we measured the internet connection latency between a number of our hospital campuses. Within the city of Orlando our latency levels were always on the order of 5 ms, which is 40 times faster than the threshold of human perception.
When crossing to other cities in the state of Florida the latency was no higher than 150 ms.
What were the results of the most recent lag time test from Florida to other States?
Following the in-Florida tests we reached out to hospitals in Fort Worth, Texas and Denver, Colorado. Both of these tests delivered latency results of less than the 300 ms which are perceptible to surgeons.
Were you surprised by these results?
We were surprised that the levels across states were not significantly higher than the city-to-city results in Florida. In this environment, latency is largely determined by the number of hops which occur on smaller network connections, as opposed to the big internet trunks that cross the country.
Overall we are surprised that latency levels have fallen to such reasonable levels since these kinds of experiments were done in the early 2000's. It looks like we really are approaching a "medical quality" internet.
In what ways could the technology be improved further?
Specific telesurgery devices are dependent upon a real customer for this kind of service. I do not think the social, medical, insurance, and legal communities are prepared to accept this as an alternative right now.
But the military is a unique customer, with unique needs, and a unique opportunity. They have the ability to fund the development of a telesurgery system and to deploy it to reach injured soldiers being brought off of the battlefield.
Defense funding kick-started the entire robotic surgery field in the late 1990's, but the communication networks were not ready for the telesurgery they envisioned.
Today the network is there. If the military used it to improve care to soldiers, that would be a huge step toward a more general civilian adoption. Until that happens, these kinds of systems are too big of a change to be embraced in a civilian medical environment.
What do you think the future holds for telesurgery?
Based on our current tests, we have determined that telesurgery is possible and generally safe today, and limitations are not due to lag time but factors associated with reliability, social acceptance, insurance and legal liability.
There are plans to test further distances in the future, but we remain confident that the networks that exist between hospitals today are more than developed enough to sufficiently support telesurgery.
Where can readers find more information?
Reader can find more information about how the study was conducted and the results by visiting https://www.nicholsoncenter.com/our-research/studies.
About Dr Roger Smith
Dr. Roger Smith is the Chief Technology Officer for Florida Hospital's Nicholson Center. He was previously the CTO for U.S. Army Simulation, Training and Instrumentation and a Research Scientist at Texas A&M University.
He remains on the Graduate Faculty at University of Central Florida and President of Modelbenders LLC. He is focused on bringing innovative technologies into medical education, treatment and services.
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