January 2018

“We sail within a vast sphere, ever drifting in uncertainty, driven from end to end.” –Blaise Pascal

TASK AT HAND: Happy New Year! It’s a new year and the Sunday Surgical Scrub returns today with two concepts worth a year of pontification. This week I’m thinking about risk and uncertainty. One of the favorite tasks I undertake on the Sunday Surgical Scrub is too analyze terms that are commonly used interchangeably but which should not. This is another example. Risk and uncertainty are frequently used to describe some aspect of unknown events or trends. Some use risk as a measure of uncertainty – this is incorrect.

Risk is a property you can measure and assess. It should be used to describe an exposure to a harm. For example, you can calculate the risk of developing lung cancer based on exposure to cigarette smoking. Risk relies on metrics to comparing populations and their relative exposure to the risk in question. Another example is the insurance industry which measures and ascribes risk for harms like disability, death or destruction of property.

How can you use risk in your approach to strategy? Look for situations where you can measure, or at the very least have comparable exposures, to assess your risk. For example, an entrepreneur hopes to open a store and is trying to decide on locations. Metrics like number of businesses in the area, income for the surrounding zip codes, employment figures, etc. can all be used to arrive at measures of viability of such a venture.

Now, uncertainty is a different beast. Uncertainty is tough to measure and, consequently, has a large degree of chance involved. The current soaring price of the digital currency Bitcoin is an example. There is a finite number of Bitcoins (approximately 21 million) so this represents a scarce digital resource with no useful metrics to analyze to assess the risk of a price decrease (or increase). Another example is weather prediction. Although sophisticated weather models exist, and we can find values for risk of rain or snow, there is still an element of uncertainty that precludes precise determination.

Uncertainty, due to the element of chance, has the opportunity for massive rewards or major losses. Whereas risk tends to lend itself to calculated gains or losses, uncertainty is where dramatic swings can occur. As a general pearl, if you can find a competitive advantage to describe uncertain outcomes, you need to develop and exploit these. These can be parlayed into a potential novel first-mover advantage or give you a significant competitive edge in market competition.

The call to action from today’s Sunday Surgical Scrub is to look for opportunities to analyze elements of risk and uncertainty in personal decisions, professional opportunities or instances involving complex decision making. Understand what the risk of exposure is and the degree of uncertainty becomes clear. The choice is then whether you want to accept that risk and uncertainty in the options available.


MEDICINE & MACULA: Wiliam Osler wrote, “medicine is a science of uncertainty and an art of probability”. These are wonderful words! Today I present a case of a young patient who suffered a retinal detachment secondary to a giant retinal tear (GRT) in the setting of trauma. Historically, surgical success rates for the management of GRTs were poor. The risks of failure from redetachment and proliferative vitreoretinopathy (PVR) were high. Modern surgical techniques have mitigated the risk of poor outcomes and improve our success rates significantly.

Here is the intraoperative view of a patient with a giant GRT secondary to trauma. Note the massive tear rolled over on itself. As mentioned above, these eyes are at high risk for the development of PVR. This case has further increased risk of PVR due to the young age of the patient.

I employed scleral buckle, vitrectomy, membranectomy, endolaser and long-acting gas tamponade (C3F8) for surgical repair. Here is the view at the end of the case.

Long-term follow-up shows an excellent outcome where the patient recovered most of their vision. You can see the laser demarcation in this montage photo.


Here is the optical coherence tomography (OCT) shows good macular anatomy and foveal architecture.


GRATIS: “There is no such uncertainty as a sure thing.” -Robert Burns


My best to you,

David Almeida


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