Effects of intravitreal indocyanine green injection in rabbits.
OBJECTIVE
To report the clinical, electrophysiologic, and histologic findings of different concentrations of indocyanine green (ICG) injected into the vitreous cavity of rabbit eyes.


METHODS
Forty-two rabbits underwent intravitreal injection of 0.1 mL of ICG in three different concentrations: 0.5 mg/mL (250 mOsm), 5 mg/mL (270 mOsm), and 25 mg/mL (170 mOsm). Fellow eyes were injected with 0.1 mL of balanced salt solution. Biomicroscopy, ophthalmoscopy, electroretinography, fluorescein angiography, and histologic evaluation were performed.


RESULTS
Eyes injected with 0.5 mg/mL of ICG showed b-wave latency delay on the first day after injection. Eyes injected with 5 mg/mL of ICG showed b-wave latency delay and decreased b-wave amplitude on the first and seventh days after injection; delayed a-wave latency on the first day after injection was also observed. Eyes injected with 25 mg/mL of ICG showed b- and a-wave amplitude and latency abnormalities during the entire follow-up. Direct correlation of increasing retinal edema proportional to the progressively increasing ICG concentrations was shown on histologic evaluation.


CONCLUSIONS
Intravitreal ICG injection in rabbit eyes may impair retinal function and morphology proportional to the progressively increasing ICG dosages.
Maia
Mauricio
M
Wilmer Ophthalmological Institute, The Johns Hopkins University School of Medicine, 550 North Broadway, Baltimore, MD 21205, USA.
Margalit
Eyal
E
Lakhanpal
Rohit
R
Tso
Mark O M
MO
Grebe
Rhonda
R
Torres
Gustavo
G
Au Eong
Kah-Guan
KG
Farah
Michel E
ME
Fujii
Gildo Y
GY
Weiland
James
J
de Juan
Eugene
E
D'Anna
Salvadori A
SA
Humayun
Mark S
MS
D000818:Animals; D004396:Coloring Agents / Q000008:administration & dosage / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004596:Electroretinography / Q000187:drug effects; D005451:Fluorescein Angiography; D007208:Indocyanine Green / Q000008:administration & dosage / Q000633:toxicity*; D007267:Injections; D008853:Microscopy; D009887:Ophthalmoscopy; D011817:Rabbits; D012160:Retina / Q000187:drug effects* / Q000503:physiopathology / Q000648:ultrastructure; D014822:Vitreous Body
D004396:Coloring Agents; D007208:Indocyanine Green