RESUMO
Objective By using a newly developed animal model of limited macular translocation (LMT) in rabbit eyes, to explore the complications,indications and predictability of LMT. Methods LMT models were performed in 15 rabbit eyes, and were divided into 4.5 mm group and 3.5 mm group by the length of scleral shortening.The effect of retinal translocation (distance and direction) and its complications were analyzed. In a separated group, postoperative corneal astigmatism was studied after release of scleral shortening suture 1 month after LMT. In order to study the impact of neuroretina retinal pigment epithelium (RPE) adhesion on LMT, retinas and choroids in 4 pigmented rabbit eyes were pretreated with photocoagulation. Results Success rate of LMT was 86 7%. In these cases, retinal translocations were achieved [(distance of 610 to 2 690 ?m, [AKx-]?s =(1 395?636) ?m; translocation angle ? of 10 38?, ?s =(22.7?8.3) ?]. The difference in scleral shortening between 4.5 mm and 3.5 mm groups did not significantly influence the final translocation. Major complications of LMT included intraocular bleeding, retinal break, and corneal astigmatism. Release of scleral shortening suture reduced corneal astigmatism and made it more regular, meanwhile, retinal translocation did not regress. The neuroretina RPE adhesion induced by retinal photocoagulation made neuroretinal hydrodissection difficult, and led to retinal break readily. . The difference in scleral shortening between 4.5 mm and 3.5 mm groups did not significantly influence the final translocation. Major complications of LMT included intraocular bleeding, retinal break, and corneal astigmatism. Release of scleral shortening suture reduced corneal astigmatism and made it more regular, meanwhile, retinal translocation did not regress. The neuroretina RPE adhesion induced by retinal photocoagulation made neuroretinal hydrodissection difficult, and led to retinal break readily. Conclusion Sufficient LMT models in rabbit eye were obtained with few postoperative complications. Direction of retinal translocation is an important factor influencing the effect of LMT, except for distance. Release of scleral shortening suture can effectively reduce corneal astigmatism without causing regression of retinal translocation. For the patients with a history of macular or para macular photocoagulation, LMT should be performed carefully.
RESUMO
Objective To investigate the preoperative design and application of the minimum foveolar translocation distance and angle of macular translocation. Methods The fundus fluorescein and indocyanine green angiographies were performed on 53 eyes of 53 patients with classic subfoveal choroidal neovascularization (SCNV), including 42 with exudative age-related macular degeneration and 11 with high myopic macular degeneration. The actual area of macular SCNV and the minimum foveolar translocation distance and angle were analyzed. Results The actual area of SCNV was 0.39~18.00 mm 2 with the mean of (3.08?3.22) mm 2. The designed minimum superior translocation distance was 67~2 240 ?m with the mean of (845.72?425.23) ?m;the minimum designed minimum inferior translocation distance was 53~ 2 430 ?m with the mean of (912.17?547.77) ?m. The minimum designed superior translocation angle was 1~32? with the mean of (13.23?6.68)?;the minimum designed inferior translocation angle was 1~35? with the mean of (14.06?8.46)?. The individual difference of the minimum designed superior and inferior translocation distance was more than 500 ?m in 16 eyes (30.19%), and the difference of translocation angle was more than 10? in 11(20.75%). Conclusion Preoperative design of minimum translocation distance and angle of macular translocation may be helpful to choose the operation program.