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It is unfortunate that much of what we need to do to the human body to treat it requires that we cut it open, as this creates a whole set of risks and complications for science and medicine. Thankfully, science and technology march on in the quest to reduce our dependence on invasive surgeries. An interesting Economist article takes a look into some of the more unconventional tools that are being explored as potential non-invasive replacements.

Let’s take a classic problem which often has a surgical solution: the removal of a cancerous tumor. How could we solve this without resorting to the use of a scalpel?

• Of course, there’s radiation – which, as we’ve discussed before, is potentially dangerous if the radiation dosage isn’t calculated sufficiently well.
• The use of ultrasound as a means to visualize what’s going on under the skin is commonly known. But a small startup in Washington called Mirabilis Medica came up with a means to use ultrasound not only to see a tumor or blood clot, but also to focus it and generate enough heat to destroy the tumor/blood clot (what they’ve called High-Intensity Focused Ultrasound or HIFU; explanatory diagram below).

• Professor Weihong Tan at the University of Florida published a paper in PNAS in early 2009 a means of using light as a way of non-invasively activating blood clotting. The system is described in the picture below, but relies on a means of inhibiting the activity of Thrombin (a protein that helps control blood clotting) with short stretches of DNA (which they’ve cutely termed “Thrombin-binding Aptamers” or TBA) that have been chemically modified to be able to change shape in the light (cis-trans isomerization under photon stimulation). The vision is to one day be able to inject a patient with these Thrombin-TBA “molecular clasps” and hit the patient with a light source, cutting off the blood flow to the tumor and all without needing invasive surgery!

These only scratch the surface of what new technologies and scientific advances might be capable of. Son et lumiere (sound and light) as surgical tools indeed!

(Image credit) (Image credit – Mirabilis Medica) (Image credit – PNAS publication)

Helpings hands? This metal-and-polymer gripper, triggered chemically, could usher in a new era of minimally invasive surgery. Credit: Timothy Leong/JHU

The other day I happened upon this article and I couldn’t help but be impressed. Today minimally invasive surgery implies smaller incisions, but incisions nonetheless. How would you like minimally invasive to mean zero incisions?  If Dr. Gracias and his colleagues have their way that may soon become a reality.

From the MIT Technology Review:

The new technology is a step toward surgical tools that move more freely inside the human body. “We want to make mobile surgical tools,” says David Gracias, a biomolecular- and chemical-engineering professor at Johns Hopkins University, who led the development of the new gripper. “The ultimate goal is to have a machine that you can swallow, or [to] inject small structures that move and can do things [on their own].”

A gripper based on the current design could respond autonomously to chemical cues in the body. For example, it might react to the biochemicals released by infected tissue by closing around the tissue, so that pieces can be removed for analysis.

Gracias and his colleagues presented the microgripper at the American Chemical Society meeting earlier this month. To demonstrate the device, they used it to grasp and maneuver tiny beads and clumps of cells in a petri dish. They have also used the device in the laboratory to perform an in vitro biopsy on a cow’s bladder. “This is the first mobile micromachine that has been shown convincingly to do very useful things,” Gracias says. “And it does not require electric power for operation.”

In it’s current iteration the gripper is maneuvered by magnets thereby removing the need for any incisions. As a scientist I can’t help but wonder when this remarkable device can be made available for laboratory use. Being able to manipulate items at a microscopic level based on chemical features could be very useful. In the meantime I look forward to a future of incision free biopsies!