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It's all relative
  1. Robert W Tarr
  1. Correspondence to Dr R W Tarr, Department of Radiology, University Hospitals Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106, USA; robert.tarr{at}

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It's poetry in motion She turned her tender eyes to me As deep as any ocean As sweet as harmony But she blinded me with science! Thomas Dolby, 1982

In 1905, Albert Einstein wrote five theoretical manuscripts which revolutionized the field of physics. He was 26 years old at the time. He had graduated from Zurich Polytechnical Institutes but had yet to obtain his doctorate degree and secure a university teaching and research position. During the time Einstein authored these five landmark articles, he was employed as a third tier patent reviewer in Bern, Switzerland.

Einstein eventually won the Nobel prize in 1921, not for what has become his most famous work, the theory of relativity, but rather for his theory of the photoelectric effect, which was one of the manuscripts published in 1905. Part of his work on the photoelectric effect dispelled the then commonly held notion that light, similar to sound, needed to be transmitted through a medium or ‘ether’ in order to be observed. Rather than acting solely as a wave, Einstein theorized that light behaved as both a wave and a particle or photon. His description of the photon property of light eventually gave birth the field of quantum mechanics which in turn was instrumental in the future descriptions of atomic and subatomic properties.

Ironically, Einstein spent most of the rest of his career and life attempting to debunk the theories espoused by proponents of quantum mechanics. What bothered Einstein most about the tenants of quantum mechanics was the application of uncertainty and probability to explain natural occurrences. As he famously stated, “God does not play dice”. Einstein became obsessed with developing a unified law which would explain the action of all elements of nature and would apply equally to the cosmos and the atom.

Unique among physicists, Einstein developed his theories through thought experiments which were bolstered by mathematical equations. He left the confirmation of proof of his ideas through experimental observation to others. Unfortunately, a unified law to explain the totality of nature could not be developed by Einstein and has yet to be developed by anyone else.

I do not have the thinking power close to what Albert Einstein possessed and yet I often find myself yearning for a unified law which could dictate my neurointerventional recommendations and actions. Similar to quantum mechanics, my treatment recommendations to patients are more often than not based on probabilities. Sometimes those probabilities are less accurate than others, depending on the quantity and quality of evidence base medicine available at the time of my recommendation. Often the probabilities which are available to me are diluted by blended data obtained from multiple subjects, and are not necessarily accurate for the individual characteristics of the patient sitting before me. I have also noticed that my recommendations have changed over time for specific patient problems and are often tempered by the most recent study results. Sometimes this makes me wonder if the advice I give today will be considered absurd 5 years hence.

I also find that the way we treat a problem is often biased by the freshness of device development. For example, when I was starting my career, a patient with a symptomatic cavernous carotid aneurysm would be evaluated with a balloon test occlusion, and if they passed the test occlusion the problem would be treated with parent artery occlusion using detachable balloons. Detachable balloons are no longer available, and many among us would currently treat the problem by placing a flow diverter, although I think the jury is still out on that.

So wouldn't it be nice for us and our patients if we knew with certainty that our recommendations were correct whether made today or 20 years from now? Wouldn't it be nice to know that 10 coils of a certain length and diameter or that any other device we apply would, with certainty, exclude an aneurysm from the circulation without risking harm to the parent artery or downstream circulation? Similarly, wouldn't it be nice to know ahead of time that if we are able to recanalize the middle cerebral artery of the stroke patient on our table they will make a significant neurological recovery? Also, wouldn't it be nice to know whether that same patient would recover without our efforts to recanalize their vessel? Wouldn't it be nice to have a universal law which predicted the outcome of all of our recommendations and treatments?

Oh well, just a thought experiment I suppose.

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  • Competing interests None.

  • Provenance and peer review Not commissioned; externally peer reviewed.

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