IOP
Just before dilating the patient the doctor will check the patient’s intraocular pressure (IOP). The eye is a hydraulic system, making and draining aqueous humor twenty-four hours a day, seven days a week. If the production of fluid does not match the drainage of fluid then pressure could build up inside the eye and when this happens it presses on the delicate optic nerve at the back of the eye. If the pressure remains high long enough, it will eventually start to crush the roughly 1.5 million optic nerve fibers leading to irreversible vision loss known as glaucoma.
The doctor measures IOP through one of the following methods.
The Perkins (Goldmann) handheld tonometer is used in conjunction with fluress which is an anesthetic mixed with fluorescein dye.
I-care is able to be used without fluress. This is useful for children who have difficulty with eye drops or for patients who may be allergic to fluorescein
At our Lewis Center office we can also do a NCT (non-contact tonometry or air-puff test) using the autorefractor, and for young children the doctor may also do palpations (feeling the softness of the eye beneath closed eyelids using fingers).
Since the Perkins (Goldmann) handheld tonometer is the most commonly used, please watch the following video on how it is performed.
And here is a video on the I-care
IOP is recorded on the workup tab as seen below.
The result should look like this.
Posterior
The Posterior portion of the exam is when the doctor uses the slit lamp or BIO to examine the interior and back of the eye, usually after the patient is dilated.
To view the peripheral retina, many doctors use a 20D lens in conjunction with the BIO headset.
BIO headset
A superfield lens used with the slit lamp is often used to view the Optic nerve and macula. This can be done whether the patient is dilated or not.
The direct retinoscope is used as an alternative to the superfield/slit lamp to view the optic nerve and macula undilated.
In order to get the best view of the structures in the back of the eye, the doctor normally dilates the patient. There are several drops that can be used to dilate: tropicamide, phenylephrine, Cyclopentolate, and Atropine. The length of time a patient stays dilated depends on the drop used, so it is very important to always use the appropriate drop.
Tropicamide is the most common dilating drop and will dilate for several hours. Comes in both 0.5% and 1% solutions.
Phenylephrine is another dilating drop, weaker that Tropicamide and is used for patients who dilate easily or can be used in addition to Tropicamide for patients who are difficult to dilate.
Cyclopentolate is used less often than tropicamide because it lasts significantly longer and is usually used on children to help the doctor get a more accurate reading of their prescription because in addition to dilating the pupil it also temporarily paralysis accommodation.
Atropine is used very infrequently because it dilates for a very long time. It is most commonly used during emergencies where a patient’s symptoms are eased by dilation.
After the patient is fully dilated the doctor will complete this portion of the exam in their dilation room. The OA is generally not present for this section of the exam. Occasionally, however, the dilation will need to be postponed. When this occurs the doctor will still check the posterior (usually right after examining the anterior) even though their views will be limited, and you will need to record any findings they observe. This data is recorded in the Exam tab on the right side of the screen.
How to record Posterior findings
If the patient dilates, check the Dilated box on the workup tab, update the time, record what eyes received drops (typically OU unless it is unusual circumstances) and select which kind of drops the doctor used from the drop-down (the doctor will tell you what kind of drops they used) and the number of drops instilled.
If the patient defers dilation, check the Refused Dilation box, update the time, and enter “Miotic” into the drops box. You will also need to enter “Miotic” into the text-box labeled Retina, and delete any text in the Periphery boxes. If dilation has been deferred, the doctor will take a look into the back of the eye, and will typically ask for the C/D ratios. This data can be found into two separate boxes in the middle of the Posterior side, labeled H and V. Simply read off the numbers in the boxes for the doctor; for example, if the right eye has the numbers 0.5 in H and 0.6 in V, you would read out “0.5 by 0.6 in the right eye.” Record changes to data as the doctor tells you.
This image highlights where the most common posterior findings belong. Many of these items will be spoken in rapid succession, so it pays to become very familiar with each findings proper location.
Please watch the following video which covers how to record posterior findings.
Introduction to Glaucoma
The following video introduces the two main types of glaucoma and how they differ from each other.
Introduction to Macular Degeneration
The following video introduces the two stages of macular degeneration: dry and wet.
Introduction to Diabetic Eye disease
The following video introduces how diabetes can affect the eye.
Introduction to Floaters and Retinal Detachments
The following videos introduce floaters (floaters vs. PVD) and different reasons why the retina can tear/detach (vitreous degeneration and epiretinal membranes/macular pucker).
Please take the Checkpoint Quiz