The first clinical trial of the Q-switched Nd:Yag laser posterior capsulotomy by using of Coherent Model 9900 in Korea was carried out since March of 1985. And only 267 aphakic eye cases(257 patients, among 680 consecutive subjects could be followed up for clinical evaluations. The results obtained are as follows: (1) 143 aphakic eyes and 58 pseudophakic eyes with 66 traumatic aphakic eyes were subjected. (2) Good results could be obtained with minimal complications by lower setting (under 1.5 ml) with mean pulse energy of 40~149. (3) Vision improvement after Nd:Yag laser up to 0.9 or more showed in 110 eyes(63%) out of 175 eyes. (4) Complications were encountered in 51 eyes(19%) but most cases were transitory without permanent damages. Vitreous prolapse with rupture of the anterior hyaloid face (14.6%) was observed more frequently in aphakic eyes than in pseudophakic eyes.
Humans ; Korea ; Posterior Capsulotomy* ; Prolapse ; Rupture

Previous reports have shown that Nd:YAG laser capsulotomy is associated with elevated intraocular pressure(IOP). Topical apraclonidine hydrochloride has been shown to be effective in preventing postlaser pressure spikes. This study was designed to compare the effect of apraclonidine hydrochloride 0.5%versus 1% in controlling IOP elevation after Nd:YAG laser posterior capsulotomy. Fourteen eyes were treated with 0.5%apraclonidine(Group 1), twenty eyes with 1%apraclonidine(Group 2)and fifteen eyes without apra-clonidine(Group 3)in Nd:YAG laser posterior capsulotomy. The mean post-operative IOP at 1 to 3 hours of Group 3(15.0+/-3.6 mmHg, 16.0+/-4.3 mmHg) was higher than Group 1(10.8+/-3.5 mmHg, 11.6+/-3.0 mmHg)and Group 2 (11.2+/-3.0 mmHg, 12.7+/-2.3 mmHg)(P<0.05)and no statistically significant difference in mean IOP was found between Group 1 and Group 2(P>0.05). This result suggests that 0.5%and 1%apraclonidine are equally effective in preventing IOP rise and 0.5%apraclonidine can be a useful adjunct in preventing IOP elevation following Nd:YAG laser posterior capsulotomy.
Intraocular Pressure* ; Lasers, Solid-State* ; Posterior Capsulotomy*

PURPOSE: This study aimed to investigate factors that cause after-cataract such as diabetes, intravitreal gas injection during vitrectomy, and other factors in relation to the vitrectomy. METHODS: The relationship between the vitrectomy and the frequency of Nd:YAG laser posterior capsulotomy was investigated in a sample of 947 monitored patients' eyes that underwent cataract surgery. The patients' eyes were classified into Group 1, which comprised 715 patients' eyes that underwent cataract surgery only, Group 2, which comprised 152 eyes that underwent both vitrectomy and cataract surgery at the same time, and Group 3, which comprised 80 eyes that underwent cataract surgery after vitrectomy. The age, gender, diabetes status, gases injected during the vitrectomy, and other factors were investigated. RESULTS: It was found that 50 eyes (6.99%) in Group 1 received the posterior capsulotomy, 28 eyes (18.4%) had the procedure in Group 2, and 16 eyes (20.00%) had the procedure in Group 3, respectively. In Group 1, 21 eyes (8.86%) that received the posterior capsulotomy were from diabetic patients, 20 eyes (19.8%) were diabetic in Group 2, and 10 eyes (21.73%) were diabetic in Group 3. In Group 1, 29 eyes (6.06%) were from non-diabetics that received posterior capsulotomy, 8 eyes (15.68%) were from non-diabetic patients in Group 2, and 6 eyes (17.64%) were from non-diabetic patients in Group 3. In the group that had vitrectomy with gas injection, 6 eyes (25%) received the posterior capsulotomy in Group 2, and 10 eyes (24.39%) had the procedure in Group 3, respectively, while those in the group that had vitrectomy without gas injection included 22 eyes (17.46%) in Group 2 and 6 eyes (15.38%) in Group 3. CONCLUSIONS: The Nd:YAG laser posterior capsulotomy was more frequently applied to patients who underwent vitrectomy, younger patients, diabetes patients, and patients who had vitrectomy with gas injection.
Cataract ; Gases ; Humans ; Posterior Capsulotomy* ; Vitrectomy*

PURPOSE: This study aimed to investigate factors that cause after-cataract such as diabetes, intravitreal gas injection during vitrectomy, and other factors in relation to the vitrectomy. METHODS: The relationship between the vitrectomy and the frequency of Nd:YAG laser posterior capsulotomy was investigated in a sample of 947 monitored patients' eyes that underwent cataract surgery. The patients' eyes were classified into Group 1, which comprised 715 patients' eyes that underwent cataract surgery only, Group 2, which comprised 152 eyes that underwent both vitrectomy and cataract surgery at the same time, and Group 3, which comprised 80 eyes that underwent cataract surgery after vitrectomy. The age, gender, diabetes status, gases injected during the vitrectomy, and other factors were investigated. RESULTS: It was found that 50 eyes (6.99%) in Group 1 received the posterior capsulotomy, 28 eyes (18.4%) had the procedure in Group 2, and 16 eyes (20.00%) had the procedure in Group 3, respectively. In Group 1, 21 eyes (8.86%) that received the posterior capsulotomy were from diabetic patients, 20 eyes (19.8%) were diabetic in Group 2, and 10 eyes (21.73%) were diabetic in Group 3. In Group 1, 29 eyes (6.06%) were from non-diabetics that received posterior capsulotomy, 8 eyes (15.68%) were from non-diabetic patients in Group 2, and 6 eyes (17.64%) were from non-diabetic patients in Group 3. In the group that had vitrectomy with gas injection, 6 eyes (25%) received the posterior capsulotomy in Group 2, and 10 eyes (24.39%) had the procedure in Group 3, respectively, while those in the group that had vitrectomy without gas injection included 22 eyes (17.46%) in Group 2 and 6 eyes (15.38%) in Group 3. CONCLUSIONS: The Nd:YAG laser posterior capsulotomy was more frequently applied to patients who underwent vitrectomy, younger patients, diabetes patients, and patients who had vitrectomy with gas injection.
Cataract ; Gases ; Humans ; Posterior Capsulotomy* ; Vitrectomy*

The cataract extraction is sometimes followed by postoperative complications related to changes in the vitreous. The lack of stability of vitreous in the aphakic eyes may be due not only to loss of the mechanical support of the lens but also to changes in the vitreous molecular composition. To define the effect of lens extraction on hyaluronic acid concentration in rabbit vitreous, six cases of rabbit eye were operated with ECCE and posterior capsulotomy equivalent to ICCE. In control rabbit group, hyaluronic acid concentration in vitreous was 202.3 +/- 77.8 ug/ml and the seventy days after surgical intervention, hyaluronic acid concentration in vitreous was 79.0 +/- 55.7 ug/ml. These result indicated that ECCE and posteror capsulotomy induced marked decrease of hyaluronic acid concentration in rabbit vitreous, which is statistically significant(p<0.05).
Cataract Extraction ; Hyaluronic Acid* ; Posterior Capsulotomy ; Postoperative Complications

We performed posterior capsulotomy on after cataract(132 eyes) by using Modelocked Nd:YAG Laser from May 1988 to september 1988. The results were as follows; 1. 72 aphakic eyes, 60 pseudophakic eyes(42 senile cataract, 61 adult cataract, 17 traumatic, 12 congenital cataract) were followed. 2. On performing posterior capsulotomy, the power setting of Nd:YAG laser ranged from 1.0 to 2.9mJ in 106 eyes(80.3%). 3. Postoperative visual acuity of 0.7 or better was achieved in 72 eyes(56.1%) and 1.0 or better in 24 eyes(18.2%). 4. Ocular complications after posterior caps ulotomy were transient increase of intraocular pressure(14,4%), intraocular lens damage(33.3%), vitreous prolapse (5.3%), transient anterior uveitis(6.1%) and cystoid macular edema(0.8%).
Adult ; Cataract ; Humans ; Lenses, Intraocular ; Posterior Capsulotomy* ; Prolapse ; Visual Acuity

We performed posterior capsulotomy on after cataract(132 eyes) by using Modelocked Nd:YAG Laser from May 1988 to september 1988. The results were as follows; 1. 72 aphakic eyes, 60 pseudophakic eyes(42 senile cataract, 61 adult cataract, 17 traumatic, 12 congenital cataract) were followed. 2. On performing posterior capsulotomy, the power setting of Nd:YAG laser ranged from 1.0 to 2.9mJ in 106 eyes(80.3%). 3. Postoperative visual acuity of 0.7 or better was achieved in 72 eyes(56.1%) and 1.0 or better in 24 eyes(18.2%). 4. Ocular complications after posterior caps ulotomy were transient increase of intraocular pressure(14,4%), intraocular lens damage(33.3%), vitreous prolapse (5.3%), transient anterior uveitis(6.1%) and cystoid macular edema(0.8%).
Adult ; Cataract ; Humans ; Lenses, Intraocular ; Posterior Capsulotomy* ; Prolapse ; Visual Acuity

PURPOSE: To compare the effectiveness of 0.2% brimonidine tartrate and that of 0.5% apraclonidine hydrochloride for controlling IOP elevation after Nd:YAG laser capsulotomy. METHODS: Thirty eyes were given with 0.2% brimonidine (group 1) and fourteen eyes with 0.5% apraclonidine (group 2) before and after the procedure. Fifteen eyes served as untreated controls (group 3). Intraocular pressure and visual acuity were measured preoperatively and 1 hour, 3 hours, 24 hours, and 1 week postoperatively in all cases. RESULTS: The postoperative mean intraocular pressures of group 3 (14.97+/-3.58, 16.47+/-3.93 mmHg) at 1 hour and 3 hours were statistically significant higher than those of group 1 (11.23+/-3.43, 11.50+/-3.01mmHg), and those of group 2 (10.79+/-3.51, 11.57+/-3.03 mmHg)(p< 0.05), but, there were no statistically significant differences in mean IOP at 1 hour and 3 hours between group 1 and group 2 (P=0.569, P=0.610). At 1 hour and 3 hours, there was no case of IOP elevation of 5 mmHg above baseline in group1 and group 2. but, there were 5 cases (33.3%) at 1 hour and 6 cases (40%) at 3 hours in group 3. CONCLUSIONS: This result suggests that 0.2% brimonidine and 0.5% apraclonidine are equally effective for preventing acute IOP elevation after Nd:YAG laser capsulotomy, that is, 0.2% brimonidine is an effective and well-tolerated agent for preventing acute IOP rises after Nd:YAG laser posterior capsulotomy.
Intraocular Pressure* ; Posterior Capsulotomy* ; Visual Acuity ; Brimonidine Tartrate

Posterior capsule opacification(PCO) is a common complication of cataract surgery. The presence of a posterior chamber intraocular lens has been shown to decrease the incidence of the development of PCO. Moreover, there are evidences that the design of intraocular lens may also alter its development. Extracapsular lens extraction with implantation of posterior chamber lens were operated on a consecutive series of 230 eyes. These were evaluated in the viewpoint of PCO development after surgery. All were sulcus fixed and their optic designs were devided into two groups; a group of convex-plano lens with continuous laser ridge including convex-concave lens and a group of biconvex lens. The incidence of PCO was lower in convex-plano lens with continuous laser ridge group(6.7%) than that of boconvex lens group(18.9%). The incidence of Nd:YAG posterior capsulotomy marked 0.0% in continuous ridged group and 1.8% in biconvex group(p<0.05, p Capsule Opacification* ; Cataract ; Incidence ; Lenses, Intraocular* ; Posterior Capsulotomy

The purpose of this study was to evaluate the susceptibility of various intraocular lenses(IOLs) of different optic material to Nd:YAG laser in vitro. Four models of IOLs manufactured by different companies were selected and ten IOLs for each model were used for this study. Two models had lathe-cut polymethylmethacrylate(PMMA) optic, one silicone compound optic, and one acrylate/methacrylate copolymer optic. Q-switched Nd: YAG laser(7901 Nd-YAG laser, Coherent, Palo Alto, CA, USA) was used. The He-Ne aiming beam was focused on the posterior surface of optic, 2mm apart from the center of optic, and sixteen shots were applied to each optic with energy levels ranging from 0.3 to 2.0mJ with increment of 0.1 or 0.2mJ in a circular pattern. The spots were examined under phase contrast microscope and scanning electron microscope. The averages(+/-SD) of energy threshold at which damage was detected were 0.49+/-0.12mJ in silicone compound optic, 0.67+/-0.19mJ in acrylate/methacrylate copolyer optic, and 0.72+/-0.11mJ and 0.89+/-0.09mJ in lathe-cut PMMA optics. All interclass differences were statistically significant except the difference between lathe-cut PMMA optic with lower damage threshold and acrylate/methacrylate copolymer optic(Mann-Whitney test, p<.05). In conclusion, silicone compound and acrylate/methacrylate copolymer optics are more susceptible to Nd:YAG laser than PMMA optic in vitro and this suggests that in patients with high risk of developing severe posterior capsular opacification after cataract surgery, implantation of IOLs with PMMA optic is preferable and early Nd:YAG laser posterior capsulotomy with low energy is recommended in cases of implantation of foldable IOLs.
Cataract ; Humans ; Lasers, Solid-State* ; Lenses, Intraocular* ; Polymethyl Methacrylate ; Posterior Capsulotomy ; Silicones