Study of krypton laser-induced choroidal neovascularization in a Guinea pig model of high anisometropia.
OBJECTIVE
To investigate the association between high anisometropia and the area of choroidal neovascularization (CNV) induced by krypton laser in guinea pigs and better understand the pathogenesis and prevention of myopic CNV.


METHODS
Nine 3-week old male guinea pigs with anisometropia >6.00D were randomly assigned to three groups according to examination date after laser photocoagulation (7d, 14d and 28d). All animals underwent refraction. The eye with higher myopia was used as the experimental eye, and the other as the control eye. All eyes received repeated multi-wavelength krypton laser photocoagulation treatments (wavelength: 532nm; laser power: 400mW; spot diameter: 50μm; exposure time: 0.1s). Fundus photography and indocyanine green angiography (ICGA) were performed. Afterwards, the animals were sacrificed immediately, and the eyes were enucleated and processed for histopathologic examination and flat mounts.


RESULTS
CNV appeared at 7d after laser treatment. The area of CNV peaked at 14d, and decrease in area and the presence of scarring was noted at 28 d. CNV was present in 66.7% of eyes by ICGA at 14 d. CNV could be observed under light microscopy at all three time points. At 14d, flat mount showed the neovascular plexus around the lesion. Semi-quantitative analysis revealed that the area of CNV in treated eyes was greater than that of control eyes.


CONCLUSIONS
Since the mechanism of CNV in this study resembles that of CNV in pathological myopia, this model can be used to investigate the etiology, pathogenesis and treatment of CNV in pathological myopia.
Medical College of Qinghai University, Qinghai 810007, China.
Jianghui
J
Wang
Wei
W
Jiang
Zefeng
Z
Kang
Lina
L
Liang
Xiaoman
X
Liu
Nannan
N
Tian
Qing
Q
Zhang
D000818:Animals; D015858:Anisometropia / Q000150:complications*; D020256:Choroidal Neovascularization / Q000209:etiology* / Q000473:pathology / Q000628:therapy; D004396:Coloring Agents; D005654:Fundus Oculi; D006168:Guinea Pigs; D007208:Indocyanine Green; D007726:Krypton; D017075:Laser Coagulation / Q000009:adverse effects; D008297:Male; D009216:Myopia / Q000628:therapy; D047728:Myopia, Degenerative; D009389:Neovascularization, Pathologic; D011897:Random Allocation; D013997:Time Factors
D004396:Coloring Agents; D007726:Krypton; D007208:Indocyanine Green