Posts

Optometry in Focus: Conjunctivitis (Pink Eye)

Happy Monday, y’all!With school back in session and cooler weather on its way, I suppose it’s time for a discussion on conjunctivitis, colloquially known as pink eye.But first, let’s start with a quick ocular anatomy review.AnatomyDespite how tempting it would be to just post a picture with fancy labels and the like, I think this section will work the best if you stop what you’re doing for a moment and find a way to look at your eye - a mirror would probably be the easiest.
What do you see?
If you’re like most people, you’ll notice the colored part, or the iris, first.  If you get really close to the mirror or change the lighting, you should be able to see a change in the size of the dark hole in the center of the iris. This is your pupil, which varies in size to adjust the amount of light coming into your eyes.
Above the iris and the pupil is the cornea.  This clear structure is difficult to truly see in the mirror, but if you wear contacts, this is what the contact drapes over.
In addit…

Contact Lenses: Ortho-K (Corneal Reshaping)

Happy Monday, y'all!In today's post, I'm taking a break from the world of neuro to answer a reader question.

JM writes: Do they still do corneal molding?  I did that for a while and loved it! I wore contact lenses at night, took them off in the morning, and could see without anything!  After a while, I didn't even have to wear them for several nights at a time and could still see!  Freedom!!First off, thank you so much for your question, JM!  And, believe it or not, yes we  still use corneal reshaping (or ortho-keratology) in practice! Keep reading to learn more!
Ortho-Keratology (Ortho-K)
What is Ortho-K?
As JM described in her question, Ortho-K is a process by which the cornea is molded by wearing specialty hard contact lenses over night to correct (myopic/near-sighted) refractive error.How It Works
This process that was first introduced in the 1960s uses a gas permeable lens design that sits directly on the cornea, rather than slightly vaulting over it, to create a flatt…

(Neuro)Optometry in Focus: Cranial Nerve Basics IV-VI

Hello, and welcome to part 2 of my Cranial Nerve Series!
In the previous post, I introduced cranial nerves and discussed the basics of CN I-III.  Ready for IV-VI? Let's get started!
CN IV: TrochlearCranial nerve IV, or the trochlear nerve, is solely responsible for controlling movement of the superior oblique muscle, which functions to help rotate the eye in an inwards motion (intorsion).  As such, CN IV is a general somatic efferent nerve.   Like the oculomotor nerve, the trochlear nucleus originates in the midbrain.  However, instead of immediately going forward towards the eyes, the trochlear nerve crosses to the opposite side, and then passes dorsally (posteriorly or to the back) out of the midbrain, and then proceeds to wrap towards the eyes.  This pathway will prove very important in my CN IV palsies post!
CN V: TrigeminalWhile CN IV was short, sweet, and to the point, the trigeminal nerve is anything but!  Trigeminal by definition means threefold, which speaks to the three prim…

(Neuro)Optometry in Focus: Cranial Nerve Basics I-III

Howdy, y'all!Since it's been a while since I wrote any neuro-related posts, I figure it's as good of time as any to begin a discussion on cranial nerves.  Let's get started!What are cranial nerves?Cranial nerves are simply the 12 pairs of nerves that originate in the brain, and then travel to various parts of the body.  Typically, these 12 nerves are referred to by roman numerals.

Before we dive further into each of the 12 cranial nerves, it's nice to have some understanding of, well, nerves.  So here it goes:Nerves can be classified in several different ways, but the most common are:SizeConduction speedFunction
OriginFor right now, I primarily want to focus on function. One major functional distinction is sensory versus motor.
Sensory nerves carry information regarding your senses to the brain.Since they are going to the brain, they are considered afferent. Motor nerves carry information from the brain to the body to create movement.Since they are coming from the bra…

Optometry in Focus: Eye Turns (Strabismus)

For those of you with children, have you ever seen your child’s eye turn in or out and wonder how concerned you should be?
In working with pediatrics, this is one of the more common questions that I am asked, and so, for tonight’s post, I’ll try to shed some light on eye turns.  Check it out! StrabismusThe BasicsEye turns, or strabismus, can be described in several ways.  The first is by consistency, with the deviation being either constant or intermittent.  The second is by time of onset - whether congenital/early onset or acquired.  Eye turns can also be described by the direction of the eye turn. In this, the eye can turn in (esotropia), out (esotropia), up (hypertropia), or down (hypotropia).  Finally, a single eye can turn, or the eyes can alternate. Who?At the end of the day, essentially anyone can have an eye turn. However, early onset eye turns may have a genetic component. Additionally, eye turns may be associated with ocular pathology or problems with the development of the bra…

Optometry in Focus: Ocular Allergies

Happy Friday y’all!First things first: how many of you haveseasonal allergies?If you’re anything like me, (especially when residing in Texas) allergy season has come to include every month of the year.  Interestingly, while most people are aware of the effects of allergies on their sinuses, I find that many people are unaware of how allergies affect their eyes.Insert today’s post!  Let’s get started!Ocular AllergiesCausesPretty much all allergic reactions in the body have the same basic cause: the body identifies something (an antigen) as a foreign entity, and decides to attack it.  Allergies specifically are associated with a Type 1 Hypersensitivity reaction, mediated by the specific antibody Ig-E.  In this, the Ig-E antibody that is specific for the antigen that you’re allergic to (ie pollen, dander, etc) binds to an immune cell called the mast cell, which contains products that are meant to destroy or remove the antigen.
The most prominent product in mast cells is histamine.  This c…

Optometry in Focus: Ocular Emergencies

Happy Monday, y’all!
One of my favorite COVID-era eye questions (thanks to 4 months of emergency care, triage, and telehealth calls to round out residency) is, “what constitutes an ocular emergency?”
(Which is closely related to, “do I really need to see a doctor for this?”)
With that in mind, today’s post is going to cover some common signs and symptoms that really do require a trip to your OD!
Flashes and FloatersFlashes and floaters are most commonly associated with a posterior vitreous detachment (not an emergency).  However, they may also be an indication of a retinal tear or retinal detachment.  If you have a sudden increase in flashes and floaters, call your eye doctor up, so that they can take a look! Loss of VisionA sudden change in vision can also be a sign of significant ocular problems.  From sudden blurry vision (that lasts more than a few seconds and doesn’t get better with artificial tears, cleaning glasses, or changing contacts), to a complete loss of vision, these changes …