The Centers for Disease Control estimates that around 2.8 million people in the United States suffer from a traumatic brain injury (TBI) every year, and vision can be affected.  Concussions are a type of TBI.

The rate of childhood TBI visits to the emergency department more than doubled between 2001 and 2009, making children more likely than any other group to go to the ER with concussion symptoms.

It was once assumed that the hallmark of a concussion was a loss of consciousness. More recent evidence, however, does not support that. In fact, the majority of people diagnosed with a concussion do not experience any loss of consciousness. The most common immediate symptoms are amnesia and confusion.

There also are multiple visual symptoms that can occur with a concussion, either initially or during the recovery phase.

Visual symptoms after a concussion include:

• Blurred vision.

• Difficulty reading.

• Double vision.

• Light sensitivity.

• Headaches accompanying visual tasks.

• Loss of peripheral...

The majority of cataract surgeries performed in the U.S. are done with a local anesthetic and IV sedation.

The local anesthesia may be accomplished in one of two ways: either an injection of anesthetic around the eye or anesthetic eye drops placed on the eye, often combined with an injection of a small amount of anesthetic into the front of the eye at the very beginning of surgery.

The injection of anesthetic around the eye generally produces a deeper anesthesia for the surgery than the topical method but it also comes with increased risk. There is a very small chance of potentially serious bleeding behind the eye and a rare chance of inadvertent penetration of the back of the eye with the injection needle.

The topical anesthesia has lower risk but does not provide quite as much numbing, although the overwhelming majority of people having cataract surgery with a topical anesthetic do not experience any significant pain during the procedure. 

The other difference between the two types...