Patient Education

This sections is the largest and most difficult section. I put this chapter first because it is good to get the largest section out of the way, but in reality the material in this chapter calls in material from chapters that come after it. You may have to jump around the a book a little to get the most out of this chapter.

Surgery

There are a lot of surgeries that patients have to have in ophthalmology. When patients have questions you are expected help answer their questions. The COA exam reflects this. It will expect you to know the differences among the many surgeries.

Oculoplastic

Oculoplastics have to do with the look of the eye. If a patient has ptosis, droopy eyelids, the surgeon will prepare a surgery to raise the eye lids. These surgeons will also preform enucleations and eviscerations. Enucleation is the removal of the entire eyeball leaving only the muscles and orbit intact. Evisceration is the removal of the entire contents of the eye leaving the sclera.

Memorization Trick

Enucleation nukes the entire eye. Evisceration leaves a visible sclera. 

Cornea

Keratoplasty is when a dying part of the cornea is replaced with donated corneal tissue. This is also known as corneal grafting or a corneal transplant.

Pterygium surgery is the removal of tissue, which grows over the cornea.

Refractive surgeries – Review my post on Assisting in Surgical Procedures under the section refractive surgery . Be able to describe LASIK, LASEK, PRK, PTK, and RK.

Muscular

Physicians can correct strabismus “crossed-eyes”. They do this by either strengthening a muscle by doing a resection or by weakening a muscle which is a recession. Resections are performed by shortening the tendon. A recession is performed by attaching the  muscle further back on the eye.

Cataracts

Cataract surgery is very common in ophthalmology. The COA exam will expect you to know a lot about cataract surgery.

Symptoms Glare – Patients will often say that they see glare from oncoming traffic while driving at night. Or see glare in a room with low lights. Halos – Halos are rings of light around a source of light. This is another common complaint. Patients will state that they see halos around headlights. Special tests related to cataract surgery are:

Corneal Topography – This makes a typographical map of the cornea which gives the provider information about the shape and curvature of the cornea. Surgeons use this while planning for cataract surgery. Read more about corneal topography here.

PAM (Potential Acuity Meter) estimates the vision a patient may have after cataract surgery. The PAM is a device which attaches to a slit lamp. When the patient looks into the PAM a visual acuity chart is seen. The visual acuity chart lights up helping the patient see it through media opacities.

BAT (Brightness Acuity Test) gives the most accurate idea of a patient’s visual disability. If a patient has a dense cataract it they will read worse when testing visual acuity with the BAT. Many insurances require that a patient have a visual acuity of ²⁰⁄₄₀ or ²⁰⁄₅₀ before they will cover the cataract surgery. The BAT helps achieve this goal. I patient with a dense cataract may have a visual acuity of ²⁰⁄₂₅, but with the BAT see ²⁰⁄₆₀.

Glaucoma

Glaucoma is death of the optic nerve. High eye pressure is associated with glaucoma. A decrease in aqueous outflow causes eye pressure to increase. Aqueous is produced by the ciliary body, flows through the pupil, over the iris, and out through the trabecular meshwork.

Open Angle Glaucoma– Open angle glaucoma is the most common form of glaucoma. It occurs when the trabecular meshwork is not functioning properly. It is like have a clogged drain. The aqueous can’t filter out effectively so more pressure builds up. Treatment for Open Angle Glaucoma- The physician will first start with drops to lower eye pressure. He will then move to a trabeculectomy. A trabeculectomy provides an alternate route for fluid to travel.  A laser is used to poke a hole in the limbus. The aqueous then flows underneath the conjunctiva. This area is a bleb. Remember Pressure = Force/Area. This surgery increases area which decreases pressure.

Closed Angle Glaucoma – There is an angle that is made between the cornea and the iris. When this angle shrinks fluid can’t drain out of the trabecular meshwork. Treatment for Closed Angle Glaucoma- The most common treatment for acute angle closure glaucoma is an Iridotomy. An iridotomy is hole that is cut in the iris with a laser. This increases the buildup of pressure that increases behind the iris.

Retina

Vitrectomy – A vitrectomy is the removal of vitreous from the eye. If a patient has had a vitreous hemorrhage the surgeon may consider performing a vitrectomy. The physician may also decide to do a vitrectomy if he wants to do retinal surgery. When a vitrectomy is performed oil or a gas bubble is placed inside the eye to help hold its shape.

Photocoagulation– Photocoagulation is the using a laser to coagulate bleeds to stop bleeding. Patients with advanced diabetic retinopathy may need photocoagulation. Anti-VEGF injections – VEGF(Vascular Endothelial Growth Factor) causes new blood vessels to grow. It most cases this is a good thing, but when this occurs in the retina it can cause vision problems. Patients that are experiencing advanced neovascularization (new blood vessel growth) may receive anti-VEGF treatments which stop neovascularization.

Systemic & Ocular Diseases

Systemic

Diabetes – High blood sugar causes problems in both the lens and the retina. Glucose is deposited in the lens. The high concentration of glucose in the lens causes a large osmolarity gradient between the concentration of glucose in the aqueous humor outside of the lens and the concentration of the glucose in the lens. To compensate for this high osmolarity gradient water moves from the aqueous to the lens which causes the lens to swell. The swollen lens causes blurry vision. In the retina two types of diabetic retinopathy (retinal death) is seen.

1. NPDR (Non Proliferative Diabetic Retinopathy) – Proliferation refers to the growth of new blood vessels. With NPDR a physician will see dots. These dots are small aneurysm of retinal blood vessels.
2. PDR (Proliferative Diabetic Retinopathy)

Hypertension – Hypertension causes ischemia(blood clots) both systematically and in the retina. When an examiner sees “cotton wool spots” he is referring to areas of ischemia on the retina.

Ocular

Please refer to my Review of Ocular Diseases post. Also review the anatomy terms below:

1. Anterior Chamber
2. Anterior Segment
3. Aqueous & Vitreous Humor
4. Bowman’s Layer
5. Bulbar Conjunctiva
6. Canaliculus
7. Caruncle
8. Ciliary Body
9. Descemet’s Membrane
10. Endothelium
11. Iris
12. Lacrimal Gland
13. Fovea
14. Lateral Canthus
15. Lens
16. Macular
17. Medial Canthus
18. Nasolacrimal Duct
19. Nasolacrimal Sac
20. Optic Nerve
21. Palpebral Fissure
22. Plica
23. Posterior Chamber
24. Punctum
25. Sclera
26. Stroma

Safety glasses

Safety glasses can be prescribed for people who weld, are at risk for chemical contact with the eye, monocular patients, and for safety in street wear. Safety lenses are lenses which are shatter resistant.

Patient Instruction

Medication

For this section I would recommend looking at pharmacology. Instruct patients to instill topical eye drops by pulling down the lower lid and looking up. Applying pressure to the lacrimal ducts will decrease the amount of solution absorbed by the body. Instruct patients to instill ointment by looking up, pulling down the lower lid, and instilling the ointment in the lower lid.

Tests

This is an overlap section. Follow the links. Supplemental Skills Visual Fields Ocular Motility Look under cover tests and stereoacuity.

Procedures & Treatments

I lumped these sections together because all of this information is covered in Assisting in Surgical Procedures This post breaks down both major and minor procedures.

Eye Dressings

Pressure patches are used to help the eye heal. The difference between a pressure patch and an eye shield is that a pressure patch keeps the eye from moving. To apply a pressure patch the technician places a patch to the eye and tapes the patch from forehead to cheek. If the patient can move their eye after the patch has been applied then it must be redone until the patient can no longer open his eye. An eye shield is used to protect the eye. Eye shield are given to patients who have had surgeries. This keeps the eye protected from external forces.

Patient Flow

When guiding a low vision patient to the exam room offer your arm. Have the patient hold near your elbow as you guide them to the room. If the provider is running behind inform the patients.

Triage

Emergencies – Must be seen within minutes

1. Chemical burns
2. Retinal artery occlusions
3. Penetrating eye injuries
4. Sudden Vision loss

Urgent – Must be seen within the same day

1. Narrow angle closure glaucoma
2. Corneal ulcer
3. Foreign body
4. Corneal abrasion
5. Acute iritis
6. Retinal detachment
7. Hyphema
8. Blow-out fracture

Semi-urgent – Should be seen within days

1. Optic Neuritis
2. Ocular tumors
3. Previously undiagnosed glaucoma

Non urgent

1. Gradual blurry vision
2. Needs new glasses

NOTE: The above list of triage cases relied heavily on The Ophthalmic Assistant 8th edition.

Formes & Manuals

This was already covered under Medical Ethics, Legal & Regulatory Issues.

Vital Signs

It is expected that all health care workers know the following

CPR

Every ophthalmic technician needs to get a CPR (Cardiopulmonary Resuscitation) certification. There will be at least one question testing your knowledge on CPR on the COA exam.

Adult CPR

1. Is the scene safe – make sure that there are no hazards.
2. Is the victim responsive – does the victim respond to a loud voice or pain?
3. Call for help – Call 9-1-1
4. Compressions – 100 compressions per minute each 2 inches in depth.
5. Airway – Tilt head back, lift chin to open airway.
6. Breathing – Pinch the victims nose closed and give a breath. Watch for chest rise and fall. Breath delivered should be a normal breath.
7. Repeat CAB (Compression, Airway, Breathing) until victim breath or help arrives.

Infant CPR

1. Is the scene safe – make sure that there are no hazards.
2. Is the victim responsive – does the victim respond to a loud voice or pain?
3. Call for help – Call 9-1-1
4. Compressions – 100 compressions per minute and ¹⁄₂ inches in depth.
5. Airway – Tilt head back, lift chin to open airway.
6. Breathing – Pinch the victims nose closed and give a very small breath. Watch for chest rise and fall. Breath delivered should be a small puff of air. Large full breath could damage the infants lungs.
7. Repeat CAB (Compression, Airway, Breathing) until victim breath or help arrives.

Check out the COA Study Guide Study For the Certified Ophthalmic Assistant Exam