13/04/2024
Stains and Dyes in Ophthalmology:
▪️Fluorescein:
▫️Concentration
➖Fluorescein strip, each containing 0.6mg to 1mg of the dye
➖1% to 2% solution also available in a bottle form
➖IV injection preparations for FFA
10% dye in a 5ml vial
20% dye in a 2ml vial
▫️Uses
➖Diagnosis of dry eye disease
*Standardized grading of corneal and conjunctival staining.
*Measurement of TBUT (tear film breakup time)
*Tear meniscus height
➖Identifying and monitoring corneal epithelial defects, corneal ulcers, corneal abrasions
➖Applanation tonometry
➖Perforating injury-Seidel's test: If a perforation and active leak exist, the fluorescein is diluted by the aqueous and will appear as a yellow-green stream (of the diluted dye) within the dark orange (concentrated) dye. This is best appreciated while using the blue filter on the slit lamp.
➖Nasolacrimal duct patency-Jones dye disappearance test: 1% to 2% fluorescein is instilled into the conjunctival sac of the eye being tested, and a cotton bud is placed in the inferior meatus
➖Trauma to canaliculus: In case of eyelid trauma, 2% dye is injected in the lacrimal apparatus using a syringe for identification of cannalicular ends to help in repair of the canaliculus.
➖FFA-5ml of 10% or 20% fluorescien is given as an IV bolus injection. A series of photographs are then taken through special filters to image vasculature and other properties in various pathologies such as diabetic retinopathy, retinal vein occlusions, age related macular degeneration (wet), and macular ischemia.
➖Contact lens fitting.
➖Off-label intraocular use in posterior segment surgeries to stain the vitreous.
▪️Lissamine Green:
▫️Concentration
1%, 2%, 3% liquid dyes
1.5mg dye impregnated strips
▫️Uses
➖Diagnosis of Dry eye disease
*In Sjogren's syndrome suspects-to rule out Keratoconjunctivitis sicca.
➖To ascertain proper fitting of contact lens, and to look for any contact-lens induced conjunctival staining.
➖In patients with symptoms of dry eye disease but no clinical signs, can be used to assess lid margins for lid wiper epitheliopathy.
▪️Rose Bengal:
▫️Concentration
1.3 mg dye impregnated strips
▫️Uses
➖Conjunctival staining
Diagnosis of dry eye disease
Dysplastic or squamous metaplastic cells of conjunctival squamous neoplasms
➖Corneal staining
Herpetic corneal epithelial dendrites, superficial punctate keratitis.
➖Eyelid Staining
Diagnosis of Meibomian gland dysfunction.
▪️Trypan Blue:
▫️Concentration
Anterior capsular staining-0.06 %
Posterior segment surgeries-0.15%
Enucleation surgery for Tenon's capsule-0.06%
▫️Uses
➖To stain the anterior capsule of lens during cataract surgeries. This is especially useful in eyes with a decreased red reflex, or weak zonules, as the dye can immediately allow the surgeon to detect a radial shift of the capsular bag.
➖To stain and strip the Descemet's membrane in Descemet's stripping endothelial keratoplasty (DSEK).
➖Aid in stripping the corneal endothelium from the donor button in Deep anterior lamellar keratoplasty (DALK).
➖To stain the Tenon's capsule after enucleation surgeries.
➖For posterior segment surgeries, to stain the ERM.
▪️Indocyanine Green:
▫️Concentration
➖40mg in 2ml for IV injections
➖0.05% to 0.5% for posterior segment surgeries, the concentration of the dye used for ILM staining depends upon the surgeon.
➖The dye comes in a 25-mg vial of ICG, which is mixed with 5 mL of the aqueous solvent that comes with it to yield the 5 mg/mL (0.5%) concentration dye, which is used to stain the anterior capsule in cataract surgeries.
▫️Uses
➖For staining the anterior capsule during cataract surgery.
➖In chromovitrectomy to visualise the ILM.
➖In ICGA, to visualise choroidal circulation, and help in the diagnosis of conditions like polypoidal choroidal vasculopathy, choroidal neovascular membrane, age related macular degeneration (wet), and posterior uveitis.
▪️Triamcinolone Acetonide:
▫️Concentration
0.1 to 0.3ml of 40mg / ml solution-for staining the vitreous.
▫️Uses
➖During vitrectomy, the dye settles as crystals on the vitreous and facilitates complete detachment and removal of the posterior hyaloid.
➖If a posterior capsular rent occurs during cataract surgery, triamcinolone can be used to know if any vitreous strands are left in AC after anterior vitrectomy.
▪️Brilliant Blue G / Acid Blue:
▫️Concentration
For ILM staining - 0.025%
▫️Uses
➖Staining the ILM in posterior segment surgeries.
Credit: www.eyewiki.aao.org & www.gjcsro.com
