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2013-04-30

Bloodless. Micro- and Nano-Surgery


Micro- and nanotechnology have started to revolutionize the one medical specialty that always held the closest of analogies to a mechanistic view of the human body: surgery.

The principles are readily obvious:
  1. The smaller the invasive mechanical tools, the smaller the required incision, the lower the need for anesthesia, and the lower the impact of overall operative trauma on the organism and the risk of infection.
  2. The smaller the invasive mechanical tools, the more likely it is that surgical (that is, mechanical) approaches can be relied on to perform the work previously entrusted to biochemical (that is, pharmaceutical) intervention with its inevitable, often extensive, and often numerous side effects, including the need to rely on complex and uncontrollable therapeutic mechanisms deemed “irrational” from a scientific perspective and generally subsumed under the notion of placebo effects.
  3. The smaller the invasive mechanical tools, the closer they come to the molecular level in the category of nanotechnology, the more the distinction between surgical and pharmacological intervention blurs. With one critical distinction, though: conventional wisdom has it that a surgical tool needs to remain under the surgeon’s control at all times whereas the molecules of any pharmacological substance by definition operate on a stochastic basis once released into the human body.
  4. The smaller the invasive mechanical tools, the lower or even inexistent the need for blood transfusions becomes – for patients who are Jehovah’s Witnesses it may be a religious tenet while for Muslims transfusions may be limited by religious concerns (such as the faith of the donor) but, aside from such considerations, procurement and management of adequate blood supply is not without substantial risks even in present times.
  5. Insertion of micro- and nano-technological mechanical tools into human vessels and body cavities entails certain challenges that can be summarized as issues of “command and control,” not unlike remote tactical direction exercised by a battlefield commander. This involves not only the direction of the tool with precision and accuracy but also fundamentally revolutionized imaging technology in order to maintain orientation, overview, and indeed overall systemic control over the operation.

It also does not surprise that technology developed for medical uses in small, tight spaces very often has multiple uses, sometimes even military, security and industrial ones.

With cardiovascular, cerebrovascular and ischemic disease but also cancer as the primary killers in the U.S. and worldwide accounting for about half of all deaths, the potential market for developing and advancing related technologies probably rivals the customer basis of the pharmaceutical industry. Even if expertise continues to become a lot more ubiquitous through telemedicine including remote surgery and videoconferencing, the cost of surgical intervention will most likely at most times and even in the very long term exceed the cost of a pharmaceutical solution – but not if the therapy requires maintenance drugs that need to be taken for extended periods or even a lifetime, or needs to be weighted by comparative effectiveness. Another factor that requires a paradigm shift in how medical care is reflected in its treatment by accounting standards is the increased promptness with which patients can go home and back to work.

Minimal procedures adapt to the size and location of the problem. Open heart surgery becomes necessary in far fewer instances and there is hope for similar developments in all locations of the human body that permit access through vessels or body cavities in some however indirect and roundabout way. But an extra hour or two of the surgical team’s time can shorten recovery periods by weeks or months, not to mention mortality risks attributable to distinguishable but still surgery-related factors such as infections, hemorrhaging, or delayed effects resulting from structural damage to tissue during surgery.

Methods based on catheters were originally developed in cardiology to address leaky heart valves, arrhythmias including atrial fibrillation (a major stroke risk), and atrial septal defects. Catheters are also the basis of balloon angioplasty and placement of drug-eluting and recently also dissoluble stents, while catheter-based zapping of nerves in the vicinity of the renal region found to be responsible for driving hypertension promises a cure for the condition. Lysis of blood clots in the brain thus far is based primarily on pharmacological methods but may eventually be assumed by nanotechnology.

The more technology advances, the clearer it becomes how many challenges remain unresolved: vascular plaques and blood clots call for maintenance of vascular walls and cardiac valves similar to that of pipe drains. With growing knowledge of dietary and environmental impact over time on our vascular system and recognition of the insufficiency of “diet and exercise,” the systemic nature of this problem and its effect on all organs becomes as obvious as the insufficiency of a solution based on pharmaceuticals alone. While medication may be effective in slowing down the process, it has rarely if ever been shown to reverse it, which would be necessary to begin speaking of a “cure“ in the sense of turning back the clock by a few decades – as would be necessary to create a significant impact on human life expectancy and quality of life.

Minimally invasive microsurgery and surgical nanotechnology are by no means limited to cardiac and vascular issues. Laparoscopic and endoscopic methods have taken over increasingly complex tasks in the abdominal cavity as well as along the entire digestive tract. Fallopian tubes and ovaries are now operated on under imaging magnification factors of 15-30x with heretofore unknown microthread material. Similar developments are taking over surgical interventions also in otorhinolaryngology and, where it is perhaps most noted by the public, in ophthalmology.

But arguably the most challenging frontier is neurosurgery. Interventions in the central nervous system as well as at peripheral nerves become increasingly possible as our tools begin to resemble a fine brush more than a sledgehammer. Operating inside the intact skull and in the extremely tricky anatomy of the spine requires miniaturization of operating tools as well as miniaturization of imaging, remote guidance, and drainage systems. This becomes increasingly accessible with continuing advances in material science, microfiber-optics and IT-supported imaging and control systems. By reducing the size of the solution to the size of the problem, surgical intervention may live up to its original mechanistic view of the human body that has been denied throughout so many centuries by mystics and spiritualists. And yet, in the molecular dimension, the mechanistic view of the body may yet surprise us with a truly spectacular renaissance. 

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