Dr. Assimellis Stuff In Dronka's Words Flashcards
Floaters
- aging vitreous-collagen fiber collapse-clumps/knots
- vitreous cortex (outer vitreous) peels from the retina-hole/break
- forward light scatter
Predisposition for floaters
High axial myopia
Diabetes
How many weeks to we have them back after we dilate them after the first time of floaters
6 weeks
This is when there is a the highest risk of RD/tears/holes after having floaters for the first time
Removal of floaters
Nd:YAG 1064=vitreolysis
Vitrectomy
Vitrectomy is still the only proven method to remove floaters. Vitreolysis can create significant issues and the risks dont necessarily outweigh the benefits
Cyclophotocoagulation procedure
- lowers IOP by decreasing production of AH. Ablated the CB epithelium.
- methods: transcleral, endoscopic
Complications of cyclophotocoagulation
Excessively lowered IOP secondary to collateral damage
Can’t see through the sclera and can see how much CB is being ablated, end up creating too much IOP drop and having hypotony. Sometimes too effective
Retinal laser therapy
Pan retinal photocoagulation
- Nd:YAH 532nm (or Argon)
- light is absorbed by the RPE-denatures protein via thermal burn-Cell death
What is PRP used for
DR
Retinal ischemia/neo
MOA of PRP
Light is absorbed by the RPE-denatures protein via thermal burn-cell death
-reduces the area of ischemic tissues-reduces total vascular endothelial growth factors (VEGF) production-reduces likelihood of neo
Complications of PRP
Chorodial effusion
Exudative RD
Macular edema
VF defects from scar tissues. They dont notice a large spot because there are a lot of smaller spots
Most commonl performed ophthalmic surgery
Cataract surgery
What laser is used for cataract surgery
Femtosecond laser
Femtosecond laser for cataract surgery
Nd:GLass 1053 (near infrared)
-creates plasma that rapidly expands, separating tissue by way of bubble formation
Pulse time < diffuse time
- significant reduction of heat affected zone
- more precise ablation
Pros of femtosecond laser for cataract surgery
More accurate ablation of crystalline lens
Less truama to surrounding tissue
Less negative outcomes
Refractive surgery
LTK PRK LASIK LASEK SMILE
LASIK/LASEK/PRL: Myopia
We want
- less optical power
- decreased curvature (Center)
We can
- flatten the cornea
- remove central tissue
LASIK/LASEK/SMILE: hyperopia
We want
- more optical power
- increased curvature (center)
We can
- steepen the cornea
- remove peripheral tissue
Phototherapeutic Keratoplasty (PTK)
Indicated for ANTERIOR corneal pathology ONLY
- spheroidal degeneration
- salzmann nodular degeneration
- band keratopthy
- RCE
- bullous keratopathy
- anterior corneal dystrophies
- superficial scars
- keratitis
Procedure for PTK
- Argon fluoride excimer laser (193nm)=photoablation
- by itself or in combination; before and/or after surgery
- reshapes the cornea which causes rapid re-epithelization
Anteiror stromal puncture indication
RCE
- trauma: organic material
- anterior corneal dystrophy: Map dot, reis-bucklers
Anterior stromal puncture procedure
Needle
- debride corneal epithelium
- puncture tissue to create hemidesmisome connections
Anterior stromal puncture with a Nd:YAG 1064
- No corneal debridement necessary***
- focused at BM
- energy: 1.8-2.2mJ. Shots ~ 1/4mm apart within subepithelium or superficial stroma
Signs of pigmentary dispersion
Kruckenberg spindle (endothelium) Iris concavity TI defects Scheie stripe (lens) Double hump sign (using 4 mirror) Excessive TTM pigment Sanpalosi line (Schwalbes)
Why do we use pilo before LPI
Tension on scleral spur pulls TM open, increased outflow
Pulls iris tight for us to see crypts
LPI setting ND;YAG 1064
Energy=3-6mJ Spit size is fixed Duration is fixed Pulses=1 Amount of burns=1-15, @ 11 or 1 oclock, 0.5-1mm in size (large enough to be patent)
Iridoplasty setttings
Power=300-500mW
Spot size=300-500um
Duration=300-500ms
Perfect candidate for YAG CAP
VA <20/30
Symptatomic
<3m post op cat sx
