Laser Procedures in Ophthalmology
Ophthalmic lasers deliver precisely targeted energy to treat various eye conditions without traditional incisional surgery. As an ophthalmic assistant, you will help set up the laser, position the patient, and assist during the procedure. Understanding what each laser does and why it is used is essential for effective patient education and clinical support.
YAG Laser Capsulotomy
The Nd:YAG laser is used to treat posterior capsular opacification (PCO), sometimes called a "secondary cataract." After cataract surgery, the posterior capsule that was left in place to support the IOL can become cloudy over time, causing blurred vision.
The YAG laser creates an opening in the opacified capsule, restoring clear vision. The procedure is quick (a few minutes), performed at the slit lamp, and typically painless. Vision improvement is often immediate.
Another YAG application is peripheral iridotomy (PI) for narrow-angle or angle-closure glaucoma. The laser creates a small hole in the peripheral iris, allowing aqueous humor to flow from the posterior chamber to the anterior chamber, relieving pupillary block and opening the drainage angle.
Selective Laser Trabeculoplasty (SLT)
SLT is a laser treatment for open-angle glaucoma. It selectively targets pigmented cells in the trabecular meshwork without damaging surrounding tissue. This stimulates a biological response that improves aqueous outflow and lowers IOP.
- IOP reduction: typically 20-30%
- Effect may take 4-6 weeks to fully develop
- Can be repeated if the initial effect diminishes over time
- Often used as first-line treatment or as an adjunct to medications
Intravitreal Injections
Intravitreal injections deliver medication directly into the vitreous cavity. The most common medications are anti-VEGF agents (vascular endothelial growth factor inhibitors), which block the protein responsible for abnormal blood vessel growth and vascular leakage.
Common anti-VEGF agents: Ranibizumab (Lucentis), aflibercept (Eylea), bevacizumab (Avastin, used off-label), faricimab (Vabysmo).
Conditions treated:
- Wet AMD: Choroidal neovascularization causing leakage and hemorrhage
- Diabetic macular edema (DME): Macular swelling from leaky diabetic vessels
- Retinal vein occlusions: Macular edema following venous blockage
The injection is performed under topical anesthesia. The assistant helps with setup, including preparing the medication, applying povidone-iodine for antisepsis, and positioning the patient.
Laser Safety
Laser safety is a shared responsibility:
- All personnel in the laser room must wear wavelength-specific protective eyewear
- The patient receives appropriate protection for the non-treated eye
- Warning signs must be posted outside the treatment room when the laser is in use
- Only trained personnel should operate or assist with laser equipment
- Filters on the slit lamp protect the operator's eyes during delivery
Key Takeaways
- YAG laser capsulotomy clears posterior capsule opacification after cataract surgery; YAG iridotomy treats narrow-angle glaucoma
- SLT selectively targets trabecular meshwork to lower IOP in open-angle glaucoma and can be repeated
- Anti-VEGF intravitreal injections treat wet AMD, DME, and retinal vein occlusions by blocking abnormal vessel growth
- Laser safety requires wavelength-specific eyewear, posted warning signs, and trained personnel
- Post-procedure IOP checks are standard after laser treatments