ABSTRACT
Background Triamcinolone acetonide (TA) is often used in the treatment of uveitis and fundus disease,but whether it has toxic effect to normal tissue around eyes is unclear.Objective The aim of this study was to explore the adverse and toxic effects of TA on the periorbitally normal tissue following the periocular injection.Methods Twenty-seven New Zealand albino rabbits were randomly divided into experimental group,normal saline solution group and blank control group.TA was periocularly injected twice (20 mg for each) at 1-month interval in the rabbits of the experimental group,and 0.5 ml normal saline solution was used in the same way in the rabbits of the normal saline solution group.Not any drug was used in the blank group.The rabbits were sacrificed 1 month and 2 months,3 months after the secondary injection.For the preparation of the specimens of extraocular muscles,peribulbus adipose tissue,lacrimal gland and optic nerve.Hematoxylin and eosin staining of the specimens was performed to examine the the pathological change under the optical microscope,and the ultrastructural of peribulbus tissues was observed under the transmission electron microscope.Results No statistically significant change was found in IOP among various time points and groups (Fgroup =0.952,P =0.881 ; Ftime =7.297,P =0.411).The hyphological structures and ultrastructure of extraocular muscles,peribulbus adipose tissue,lacrimal gland and optic nerve were normal in the rabbits of the normal saline solution group and the blank control group.However,the optical microscopy showed varying degrees of atrophy or dissolving in the extraocular muscle fibers,the increase of glandular epithelial cells and enlargement of nuclei in the lacrimal gland as well as visible disorder arrangement of nerve fibers,vacuoles degeneration and the decrease of glial cells in optial nerve tissue in the rabbits of the experimental group from 1 month though 3 months after the secondary injection.Under the transmission electron microscope,the muscle stripes,bright band and dark band were incompletely disappeared,and expansionary sarcoplasmic reticulum and oval nucleus at the inferior to sarolemma were seen in the extraocular muscles.In addition,swelling lacrimal gland epithelial cells,thickening nuclear membrane and more organelles were exhibited in the lacrimal gland.In the optic never tissue,uneven myelin,space between axons and myelin,lamellar separation and degeneration also were revealed in the rabbits of the experimental group after injection of TA.Peribulbus adipose tissue was near normal both by optical microscope and transmission electron microscope in the experimental group.Conclusions The periocular injection of TA dose not elevated the IOP.However,it will result in the histogical and ultrastructural damages of extraocular muscles,lacrimal gland and optic nerve.
ABSTRACT
Background Refractive regression is a common complication of high myopia after laser in situ keratomileusis (LASIK),and it affects the stability of surgery.Objective This study was to observe the preventive effect of timolol on refractive regression in high myopia after LASIK.Methods A perspective randomized controlled trial was performed under the approval of Affiliated Hospital of Zunyi Medical College and the informed consent of the patients.Sixty eyes of 60 patients with high myopia (-7.16±0.95) D for LASIK were randomized into experimental group and control group.Regular eye drops were topically administered in the patients after LASIK in both groups,and timolol 0.5 ％ was added topically from 1 day after LASIK.The uncorrected visual acuity (UCVA),best corrected visual acuity (BCVA),spherical equivalent (SE),corneal anterior surface curvature,intraocular pressure (IOP),central corneal thickness (CCT) were measured before LASIK,1 week,1 month,3 months and 6 months after LASIK,respectively.Residual stromal bed thickness was calculated before LASIK.The differences of above-mentioned indexes were analyzed and compared between the two groups and among the various time points using repetitive measurements analysis of variance,independent simple t test and Bonferroni test.Results No significant differences were found in the demography between the experimental group and the control group,including age,UCVA,BCVA,SE,IOP,corneal anterior surface curvature,CCT and residual stromal bed thickness (all at P＞0.05).UCVA was significantly different between the two groups among various time points (Fgroup =3.91,P＜0.05 ; Ftime =3.80,P＜0.05),and the UCVA was significantly higher in the experimental group than the control group 6 months after LASIK (t=2.97,P＜0.05),and UCVA was gradually increased as the lapse of postoperative time with the significant difference between 7 days and 6 months after LASIK in the experimental group (P＜0.05).No significant difference was seen in the BCVA between the two groups at various postoperative time points (Fgroup =2.44,P＞0.05;Ftime =2.31,P＞0.05).SE refraction in both groups were significantly reduced from 7 days through 6 months after LASIK,showing significant difference between the groups at various time points after LASIK(Fgroup =11.52,P＜0.05;Ftime =22.06,P＜0.05).The SE refraction was higher in the experimental group than that in the control group 6 months after LASIK (t =2.47,P＜0.05).Corrected IOP in the experimental group was lower than that of the control group at 7 days,1 month and 3 months after LASIK,respectively (Fgroup =14.83,P＜0.05).The change of CCT was not statistically different between the control group and the experimental group (Fgroup =0.04,P＞0.05).The anterior corneal surface curvature was steady in the experimental group during the following-up duration after LASIK,while the control group was growing gradually (Ftime =18.73,P＜0.05).Conclusions The study data show that topical administration of 0.5％ timolol early in high myopia following LASIK is effective for the reduction of the refractive regression.It is suggested that 0.5％ timolol can prevent cornea ectasia by lowering IOP.Reduction of the IOP may contribute to improving the regression after keratorefractive surgery in high myopic eyes.
ABSTRACT
Background Glucocorticoid drugs have been used increasingly in ophthalmology.It has been established that glucocorticoid are associated with a rise in intraocular pressure (IOP) and the development of glaucoma.Selective laser trabeculoplasty (SLT) is thought to be effective in treating patients with glucocorticoidinduced elevated IOP.Objective This study was to assess the efficacy of SLT in lowering IOP in patients with glucocorticoid-induced ocular hypertension.Methods A retrospective case series study was adopted.SLT around 360° chamber angle was performed in 9 eyes of 9 patients with glucocorticoid-induced glaucoma in Eye & ENT Hospital of Fudan University,including 5 eyes of 5 patients owing to use of glucocorticoid eye drops for long-term after laser in situ keratomileusis (LASIK) and 4 eyes of 4 patients who received intravitreal injection of 0.1 ml triamcinolone acetonide (TA) (4.0 mg) for macular edema induced by central retinal vein occlusion(CRVO).All of the patients were lack of preexisting glaucoma or ocular hypertension and underwent unsuccessful maximum tolerated medical therapy before SLT treatment.The base IOP was 35-44 mmHg and glucocorticoid drugs were ceased for 2-12 months prior to the SLT.The patients were followed-up for 6 months.IOP was measured and recorded before and 1 hour,1 week,1 month and 3 months,6 months after SLT.The difference of IOP was compared by repeated measures analysis of variance and multiple comparison analysis.Results All the patients received single SLT operation.The mean IOP was (40.0±2.9) mmHg before operation,but the IOP was (37.9±8.1),(34.9±5.9),(27.6±6.7),(21.6±6.9) and (17.9±2.9)mmHg 1 hour,1 week,1 month,3 months and 6 months after SLT.The IOP at 1 month,3 months and 6 months after SLT were significantly lower than that before operation (all at P＜0.05).Two patients received a filtration surgery for uncontrolled IOP at 1 month and 3 months after SLT respectively,and another patient still used 2 kinds of lowing-IOP eye drops until the end of following-up duration.Conclusions SLT reduce IOP in 6 eyes of 9 patients with glucocorticoid-induced increased IOP from the initial 1 month through 6 months after SLT.