Comparison of visual quality following different methods of YAG laser posterior capsulotomy for posterior capsular opacification / 中华实验眼科杂志

Objective To evaluate and compare the subjective and objective visual quality of YAG laser posterior capsulotomy.Methods A series of case observation study was designed.Twenty-eight patients (38 eyes)underwent Nd:YAG laser posterior capsulotomy in the Eye Hospital of Wenzhou Medical University were retrospectively collected from 2015 to 2016.Patients were divided into circular capsulotomy group (20 patients 23 eyes) and cruciate capsulotomy group (12 patients 15 eyes) based on the capsulotomy technique (round incision of posterior capsule or cross incision of posterior capsule).The uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) were examined before and 2 weeks after operation,the intraocular pressure was also measured before operation,1 hour after operation and 2 weeks after operation.The Strehl ratio (SR),modulation transfer function (MTF) cut-off,objective scatter index (OSI),OQAS values (OVs) were analyzed by Two-channel visual quality analysis system OQAS Ⅱ at 1 h and 2 weeks after operation.The changes of intraocular scattering and visual quality at 1 h and 2 weeks after operation with different posterior capsulotomy methods were compared and analyzed.Results At 2 weeks after operation,the UCVA was 0.18±0.15 and 0.16±0.14,and the BCVA was 0.10±0.10 and 0.10±0.11,respectively in the circular capsulotomy group and cruciate capsulotomy group,which was higher than those before operation (all at P＜0.05),but there was no significant difference in UCVA and BCVA between the two groups (all at P＞0.05).There was no significant difference in intraocular pressure between the two groups at 1 hour and 2 weeks after operation (both at P＞0.05).In the circular capsulotomy group,the incidence of black shadow drift was 39.1％ and 30.4％ respectively at 1 hour and 2 weeks after operation,which was higher than that in the cruciate capsulotomy group (6.7％ and 6.7 ％),with no significant differences between the two groups (P =0.065,0.177).No significant difference were found in the incidence of black shadow drift before eyes between the two groups (P＞0.05),and there was no significant differences in the OQAS parameters OSI,MTF,SR,OV100％,OV20％ and OV9％ between the two groups (all at P＞0.05).Conclusions After Nd:YAG laser capsulotomy,the incidence of black shadow drift in the cruciate capsulotomy group is lower than that in the circular capsulotomy group.There is no significant difference in the visual acuity,intraocular pressure,intraocular scattering and visual quality parameters between circular posterior capsulotomy and cross posterior capsulotomy.

Effect of Nd:YAG Laser Capsulotomy on Anterior Segment Parameters in Patients with Posterior Capsular Opacification after Phacovitrectomy

PURPOSE: To compare changes in anterior segment parameters after Nd:YAG laser capsulotomy in eyes that underwent either combined phacovitrectomy or cataract surgery. METHODS: This retrospective study enrolled 37 eyes of 35 patients with posterior capsular opacification treated with combined phacovitrectomy (group A), and 35 eyes of 32 patients with posterior capsular opacification treated with cataract surgery (group B). Anterior segment parameters, including anterior chamber depth (ACD), anterior chamber angle, and anterior chamber volume, were measured by a Pentacam before Nd:YAG laser capsulotomy and 1 hour, 1 day, 1 week, 1 month, and 3 months after this treatment. RESULTS: In the cataract surgery group, the ACD was significantly lower 1 day (3.75 ± 0.74 mm), 1 week (3.73 ± 0.24 mm), and 3 months (3.74 ± 0.33 mm) after Nd:YAG laser capsulotomy compared with the pretreatment value (4.20 ± 0.62 mm, p = 0.002). By contrast, the ACD did not change significantly over time in the combined phacovitrectomy group. The ACD differed significantly between the two groups at 1 week, 1 month, and 3 months after capsulotomy. There were no significant changes in the anterior chamber volume, anterior chamber angle, central corneal thickness, or pupil size from before to after capsulotomy in either group. A non-significant trend toward myopic shift was observed in group A (p = 0.072) and B (p = 0.055). CONCLUSIONS: The results of the present study may help determine the power of the intraocular lens in patients who underwent combined surgery or cataract surgery and who will receive Nd:YAG laser capsulotomy.

The Influence of Vitrectomy of Nd:YAG Laser 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.

The Influence of Vitrectomy of Nd:YAG Laser 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.

Brimonidine 0.2% versus Apraclonidine 0.5% for Controlling Intraocular Pressure Elevation after Q-switched Nd:YAG Laser Posterior Capsulotomy

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 Change Following Nd: YAG Laser Posterior Capsulotomy in After Cataract

Intraocular pressures (IOP)were measured following Neodymium (Nd): YAG laser posterior capsulotomy in 51 pseudophakic eyes which had been treated with phacoemulsification and intraocular lens in the bag.Group 1 was no medical treated, group 2 was treated with 0.5%apraclonidine preoperatively, group 3 was treated with fluorometholone postoperatively, and group 4 was treated with 0.5%apraclonidine preoperatively and with fluorometholone postoperatively.IOP was measured preoperatively and 1, 3, 24 hours and 1 week postoperatively.Four eyes (7.8%)had greater than 5 mmHg elevation of IOP (1 eye in group 1, 3 eyes in group 3)and all of them decreased IOP to normal level within 3 hours.In summary, there was no or little IOP elevation without any medical treatment in eyes which had been treated with phacoemulsification and intraocular lens in the bag and had intact posterior lens capsule.

The Effect of Apraclonidine Hydrochloride 0.5%Ve rsus 1%for Controlling Intraocular Pressure Elevation after Nd :YAG Laser Posterior Capsulotomy

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)(P0.05). 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.

Clinical Analysis for Complications of Nd-YAG Laser Posterior Capsulotomy in Uveitis Patients

Nd-YAG laser is known as a safe and effective treatment for posterior capsular opacity after cataract surgery. We studied the ocular complications after Nd-YAG laser treatment in uveitis patients. From January 1991 to December 1996, we retrospectively investigated the complications of uveitis in 22 persons(25 eyes) after Nd-YAG laser posterior capsulotomy, and also investigated that of nonuveitis in 563 persons(635 eyes) as a control group. The uveitis cases consisted of six anterior uveitis, eight intermediate uveitis, seven Behcet`s syndromes, three panuveitis, and one posterior uveitis. In the uveitis group, the complications(18 eyes) consisted of three retinal detachments, one giant retinal tear, three glaucoma, two aggravations of uveitis, two vitreous opacities, one retinal emorrhage, one proliferative vitreoretinopathy, one hyphema, and four transient high intraocular pressures(IOP), and in the control group, it consisted of two subluxations of intraocular lens(IOL), three glaucomas, one retinal tear, three transient high IOPs, two vitreous opacities, two retinal hemorrhages, three macular holes, two retinal detachments, and five cystoid macular edemas. From our experience, the incidence of complications after Nd-YAG laser posterior capsulotomy in uveitis was higher than that in nonuveitis. It was also noted that it is necessary to follow up thoroughly the complications after Nd-YAG laser posterior capsulotomy in uveitis patients.

Development of After-cataract in Pseudophakic Eyes with Silicone or PMMA Intraocular Lens

Foldable intraocular lenses(IOLs) arebeing used and wide spread with some advantages such asn little surgically induced astigmatism and rapid visual rehabilitation, but the effect of foldable IOLs on long-term safety and the formation of after-cataract was not understood clearly yet. 48 patients(54 eyes) which underwent Nd-YAG capsulotomy from 1995 to 1997 at the Kangnam St. Mary`s Hostpital were studied. All the cases had been operated by one operator(Joo) with the same technique except for incision method. The average interval from cataract surgery to Nd-YAG capsulotomy was 31 months in PMMA group and 15 months in silicone group. This difference between the two groups was statistically significant(P=0.0002). The ratio of Elschnig pearl type to fibrosis type in after-c attract was 16:6 in PMMA group and 13:18 in silicone group. The average of the total energy used in Nd-YAG laser capsulotomy was 256mJ in PMMA group and 309mJ in silicone group. However, damages caused by YAG laser were severer and more common on the silicone IOLs than on the PMMA IOLs. Silicone IOL induces after-cataract faster than PMMA IOL and the major type of after-cataract in pseudophakia with silicone IOL is fibrosis.

The Rate of Posterior Capsular Opacification with Three Different Sizes of Capsular Intraocular Lenses

A prospective study was carried out in 124 cataract patients(140 eyes) to evaluate the rate and degree of the opacification and/or wrinkling of the posterior capsule after in-the-bag placement of 6 mm optic capsular IOLs-12.0mm, 12.5mm and 13.0mm loop to loop total length were inserted. Cases only with intact CCC(continuous curvilinear capsulorhexis) and in-the-bag placement of PCLs (posterior chamber lenses) were included but any case of operative complications were not included. The rate and degree of opacification and/or wrinkling of the opsterior capsule were observed at 1 week, 1 month, 2 months, 3 months, 6 months, and 12 months after operation, respectively. Posterior capsular wrinkling with striae increased with total length of capsular IOL up to postoperative 1 month but thereafter there were no significant differences among the three different sizes of I0Ls througthout the follow up periods. The differences of rate and degree of posterior capsular opacification among IOLs were not statistically significant during the follow up periods. Mild degree of IOL decentration -0.5mm to 1.0mm pccired in 10 eyes(7%). Nd/Yag laser posterior capsulotomy was done in 3 eyes(2%).