Full-field ERG tests the entire retina’s electrical response to light. You get electrodes on the cornea or skin, dark-adapt for ~20 mins, then flashes of light stimulate rods and cones. It records a-waves (photoreceptor activity) and b-waves (inner retinal response). Used to diagnose widespread retinal diseases like retinitis pigmentosa or Leber congenital amaurosis. Results show overall retinal function, not localized areas.
GENE THERAPY
Gene therapy for Leber congenital amaurosis (LCA) delivers a functional copy of a mutated gene to retinal cells, usually using an adeno-associated virus (AAV) vector injected under the retina. The first FDA-approved treatment, Luxturna, targets RPE65 mutations and has shown improved night vision and visual fields in many patients.
- Process: A tiny surgical incision allows subretinal injection of the viral vector carrying the healthy gene.
- Outcome: Can restore some visual function, especially in dim light, but not full sight.
- Limitations: Effective only for certain mutations; benefits vary, and it’s not a cure.
- Risks: Includes inflammation, retinal detachment, or increased eye pressure.
- Research: Ongoing trials for other genes like CEP290 and GUCY2D.
AIR PUFF TONOMETER
👓 The air puff tonometer is a non-contact device that measures intraocular pressure (IOP) by blowing a quick puff of air onto the cornea.
- How it works: The device measures the corneal deformation caused by the air puff.
- Advantages: No direct contact with the eye, reducing infection risk.
- Common use: Often used for glaucoma screening and routine eye exams.
- Considerations: Can be less accurate than contact tonometers (e.g., Goldmann).
CATALIN
👨⚕️ Catalin is a topical eye drop for cataract management.
Key points:
- Active ingredient: Sodium 1-hydroxy-5-oxo-5H-pyrido[3,2-a]phenoxazine-3-carboxylate
- Antioxidant properties: May reduce oxidative stress in the lens
- Usage: Instill 1-2 drops, 3-4 times daily
Potential benefits:
- Slows cataract progression: May help delay surgery
- Antioxidant effect: Protects lens proteins
Notes:
- Consult an eye doctor: For proper diagnosis and treatment
- Not a cure: Management tool
MIOTIC DRUGS
👨⚕️ Miotic drugs constrict the pupil (miosis) and reduce intraocular pressure (IOP). Used for glaucoma, post-surgery, or counteracting mydriasis.
Common examples:
- Pilocarpine (cholinergic)
- Effect: 1–2 hours, lasts 4–8h.
- Use: Open-angle glaucoma, miosis.
- Side effects: Headache, dim vision, brow ache.
- Carbachol (cholinergic)
- Effect: Strong, longer-lasting.
- Use: Glaucoma, post-op care.
- Risk: Retinal detachment risk.
- Acetylcholine (direct-acting)
- Use: Intraocular surgery (short-acting).
- Echothiophate (anticholinesterase)
- Use: Chronic glaucoma.
- Risk: Cysts, systemic toxicity.
Precautions:
- Night vision issues: Avoid driving in low light.
- Retinal risk: Check for detachment symptoms.
- Asthma/COPD: Caution (bronchospasm).
- Tapering: Avoid sudden stop.
VON GRAEFE TEST
The Von Graefe test, also known as the Von Graefe’s prism test, is used to measure the amount of heterophoria (latent strabismus).
What it’s for:
The Von Graefe test is used to:
- Measure heterophoria (latent strabismus)
- Assess binocular vision
How it’s done:
- The patient is asked to look at a target.
- A prism is placed in front of one eye.
- The prism is adjusted until the patient reports alignment of the target.
- The amount of prism required to align the target measures the heterophoria.
PREVENTING BACTERIA CONJUNCTIVITIS
Bacteria conjunctivitis is an inflammation of the conjunctiva, caused by bacteria.
Bacteria conjunctivitis is contagious, hence it can spread from person to person and it is also very easy to get reinfected over and over again if precautionary measures are not taken.
To prevent bacteria conjunctivitis, do the following..
- Wash your hands regularly,
- Avoid touching your eyes with your hands.
- Disinfect your surroundings and change your beddings regularly
- Avoid sharing eyedrops
- Avoid using contaminated eyedrops
- Ensure that nothing touches the tip of your eyedrop dropper.
