I have always believed that only a single refraction and its spherical equivalents can produce the best-corrected visual acuity (BCVA) for any given person. Assuming that human intelligence allows for accurate estimation of Snellen acuity even without crisp vision, there should only be a narrow range of refractions that can be tolerated. After reviewing some refraction notes from a clinician’s office, I’m shocked:

2006: OD: -1.00 -1.50 x 080 OS: -7.00 -0.50 x 040

2007: OD: -1.25 -1.00 x 099 OS: -8.50 +1.00 x 160

2008: OD: -1.00 – 0.75 x 095 OS: -7.50 – 1.00 x 060

Even at first glance, there are multiple inconsistencies in these notes. The refractions came from a large academic practice, and the 2006 and 2007 refractions even came from the same optometrist. The patient had never undergone any eye surgeries, but was an elderly person.

Why the hell was the OS examination from 2007 written in plus cylinder notation? The conversion doesn’t even match up with either of the other two exams. If you look only at the right eye, the axis changed every year, as did the cylindrical power. As far as I understand, there are published tables on the tolerated range of axes for a given astigmatic correction. A correction of 1D with an axis fluctuation of up to 19-degrees (80 to 99) does not seem tolerable.

Unfortunately, I don’t have the acuity for each refraction to verify the results.

medicine ophthalmology

Several months ago I released an online intraocular lens calculator featuring three of the commonly used power calculation formulas, as described in the peer-reviewed literature. I received 82 hits on the page the first day it opened, and amassed about 400 total hits in one week. That is considerable for an unadvertised website.

Due to legal pressures, I was forced to remove it online. This is unfortunate, because there are no other freely available, web-based calculators. Granted, most modern A-scan devices have these formulas built into them, but there is something to be said for crunching a few calculations without hunting down the scanner in the building. Too bad.

computing, medicine

This photo is from a guy who ended up having a penetrating corneal injury from a thorn. Apparently he was running through the woods in the dark, and came across a brier patch. Lesson learned…

A few issues to note when repairing corneal lacerations with foreign bodies:

• Make note of the direction of entrance. In some instances, it is easier to remove the foreign body from the direct it enters the globe.
• Composition of foreign body. If plant matter is involved, think of Bacillus cereus. You’d want to cover this organism with the appropriate antibiotics.
• Do not inject gentamicin intracamerally. You will kill the retina if anything greater than 100-ug goes intraocular.
• Make note of the tension of the sutures passed. At times it is tempting to tighten the knots as much as possible, but that is often unnecessary. You just want a water-tight seal without inducing too much astigmatism.

medicine ophthalmology

To think we’ve been using this A-scanner for our axial length measurements for cataract surgery. Circa 1970′s-style. We did get a new one recently…it’s white instead of yellow.

medicine ophthalmology

I’ve always suspected that physicians have a narrower breadth of knowledge than the average professional, especially in non-medical issues. After all, college and medical school for them consisted of learning organic chemical processes and bizarre diseases.

My suspicion was confirmed recently during a friend’s wedding. A portion of the wedding lunch was dedicated to “wedding trivia”. It wasn’t the typical trivia about the bride and groom one would know from being their acquaintances, but rather hardcore minutiae a la trivial pursuit.

Topics included politics:

What is the term used to describe unintended civilian consequences resulting from covert operations from an aggressor government?

And science:

What is the name used to describe the first primitive bird considered to be descended from dinosaurs?

The teams were divided by dinner tables. My table consisted of internists, nephrologists, and other physicians. We placed near the bottom of the competitor list, behind the lawyer table (trivia nights at the pub must have given them an advantage) and all of the tables with PhD’s.

Conclusion: We spend too much time studying diseases that have no cures.

Note: The answers to the aforementioned questions are “blowback” and “Archeopteryx”, respectively.

medicine humor, medicine