A new technique for Nd:YAG laser posterior capsulotomy

AIM:To investigate the effects of a new opening pattern in neodymium:yttrium-aluminum-garnet(Nd:YAG)laser posterior capsulotomy on visual function.METHODS:This technique was conducted along a circular pattern.The energy ranged between 0.8 and1.2 mJ/pulse was consumed and mean total energy levels were 74±21 mJ(mean±standard deviation:SD,from 40 to167)and laser shots aimed at 150μm away behind a datum point and went along an imaginary line which extends 0.5 mm inside from optic margin and into the circular en bloc pattern.Vitreous stands were attached with fragment and then they were cut off by the laser after circular application.The circular fragment was completely separated from vitreous,and then this fragment was quickly sunk in intravitreal space.RESULTS:The follow-up period ranges from at least a week to 40mo,making 15.8mo on average.The procedural outcome showed 96%(74 eyes out of the 77eyes)enhancement in patients’visual acuity.Cystoid macular edema or retinal detachment was not observed in any of the patients during follow-up periods.CONCLUSION:This new technique is expected to improve the weaknesses that the conventional procedures have by adding the process to cut off vitreous stands attached with the fragment by the laser to the circular application.

Comparison of two Nd:YAG laser posterior capsulotomy: cruciate pattern vs circular pattern with vitreous strand cutting

AIM： To investigate the effects and safety of neodymium： yttrium-aluminium-garnet（Nd：YAG） laser posterior capsulotomy with vitreous strand cuttingMETHODS： A total of 40 eyes of 37 patients with symptomatic posterior capsular opacity（PCO） were included in this prospective randomized study and were randomly subjected to either cruciate pattern or round pattern Nd：YAG posterior capsulotomy with vitreous strand cutting（modified round pattern）. The best corrected visual acuity（BCVA）, intraocular pressure（IOP）, refractive error, endothelial cell count（ECC）, anterior segment parameters, including anterior chamber depth（ACD） and anterior chamber angle（ACA） were measured before and 1 mo after the laser posterior capsulotomy. RESULTS： In both groups, the BCVA improved significantly（P〈0.001 for the modified round pattern group, P=0.001 for the cruciate pattern group）; the IOP and ECC did not significantly change. The ACD significantly decreased（P〈0.001 for both） and the ACA significantly increased（P=0.001 for the modified round pattern group and P=0.034 for the cruciate group）. The extent of changes in these parameters was not significantly different between the groups.CONCLUSION： Modified round pattern Nd：YAG laser posterior capsulotomy is an effective and safe method for the treatment of PCO. This method significantly changes the ACD and ACA, but the change in refraction is not significant. Modified round pattern Nd：YAG laser posterior capsulotomy can be considered a good alternative procedure in patients with symptomatic PCO.

Stability of neodymium:YAG laser posterior capsulotomy in eyes with capsular tension rings

·AIM: To evaluate the stability of neodymium(Nd):YAG laser posterior capsulotomy in eyes with capsular tension rings(CTRs).·METHODS: A total of 60 eyes that underwent cataract surgery and laser posterior capsulotomy postoperatively were included in this retrospective cohort study. To evaluate the safety and stability of capsulotomy, changes in the size of posterior capsulotomy and anterior chamber depth(ACD) in three groups: the group without CTR, the group with 12 mm CTRs, and the group with 13 mm CTRs, at 1wk, 3, 12, and 15mo after capsulotomy, were compared. ·RESULTS: In the group without CTR and the group with 12 mm CTR, there was no significant change in ACD at every post-laser follow-up. In the group with 13 mm CTR, the ACD change was significant until 3mo after capsulotomy. In all groups, there was a significant increase in the area of capsulotomy between 1wk and 3mo post-laser. Between 3 and 12mo post-laser, only the group with 13 mm CTR showed a significant increase in the area of capsulotomy(P<0.01). ·CONCLUSION: Laser posterior capsulotomy is safe in all three groups. The capsulotomy and ACD become stabilized and have not shown significant changes since 1y postlaser, even with larger CTRs. The maintenance of centrifugal capsular tension can last longer with larger CTRs, and the stability of the capsulotomy site can be reached about 12mo after capsulotomy in pseudophakic eyes with larger CTRs.

Induction of oxidative stress in human aqueous and vitreous humors by Nd:YAG laser posterior capsulotomy

AIM： To evaluate whether the Q-switched Nd：YAG laser treatment applied in routine capsulotomy elicits oxidative stress in aqueous and vitreous humors. METHODS： Thirty-six patients who had to undergo a 25 gauge pars plana vitrectomy due to vitreoretinal disorders were enrolled, 15 of them underwent a Q-switched Nd：YAG laser capsulotomy 7 d before vitrectomy due to posterior capsule opacification（PCO）（Nd：YAG laser group） while the remaining 21 patients were not laser treated before vitrectomy（no Nd：YAG laser group）. Samples of the aqueous and vitreous humors were collected during vitrectomy from all patients for the assessment of oxidative parameters which were compared between the Nd：YAG laser group and no Nd：YAG laser group. Thiobarbituric acid reactive substances（TBARS）, a product of membrane lipid peroxidation, nitrite levels, the antioxidative activities of SOD and catalase, the 4-HNE-protein conjugate formation, indicating structural modifications in proteins due to lipoperoxidation, were assessed in aqueous and vitreous samples. RESULTS： In the human vitreous humor TBARS levels are significantly higher in the Nd：YAG laser group compared to the no Nd：YAG laser group and importantly, there is a significant correlation between the TBARS levels and the total energy of Nd：YAG laser used during capsulotomy.Moreover the anti-oxidative activities of SOD and catalase were significantly decreased by Nd：YAG laser treatment, both in aqueous and vitreous humors. In accordance with the TBARS data and anti-oxidative enzyme activities, significantly higher levels of proteins were conjugated with the lipoperoxidation product 4-HNE in the aqueous and vitreous humors in the Nd：YAG laser-treated group in comparison to no Nd：YAG laser group. CONCLUSION： These data, clearly suggest that any change that Q-switched Nd：YAG photo disruption may cause in the aqueous and vitreous compartments, resulting in a higher level of oxidative damage might be of considerable clinical significance particularly by accelerating the aging of the anterior and posterior segments of the eye and by worsening the intraocular pressure, the uveal, the retinal（especially macular） pathologies.

Effect of Anterior Capsule Polishing on the Need for Laser Capsulotomy

Purpose: To determine the effect of anterior capsule polishing (APC) on the rate of posterior capsule opacification (PCO) as assessed by the need for laser posterior capsulotomy. Setting: University-based clinical practice, Jules Stein Eye Institute, Los Angles, California, USA. Methods: This study involved a retrospective review of eyes that underwent phacoemulsification and intraocular lens implantation between September 1991 and June 1999. Lens epithelial cells in the 763 study eyes were mechanically debrided or polished from the inside surface of the anterior capsules using a pair of Shepherd-Rentsch (Morning STAAR Inc.) capsule polishers. The 484 control eyes that had surgery earlier in the series were not polished. The rate of laser capsulotomy in the ACP and the non-ACP groups was compared using a Kaplan-Meier survival analysis. Multivariate regression was performed to determine if variables other than ACP influenced the need for laser posterior capsulotomy. Results: We identified 763 eyes that had ACP and 484 that did not. At the 24-month follow-up interval, 26.6% of the eyes in the ACP group had received a capsulotomy versus 19.50% in the non-APC. Next, a separate study was done using only one eye per patient, taking the patient as the unit of analysis. Again the capsulotomy rate was higher in the ACP group compared to the non-ACP (1.02 per 100 person-months of follow-up vs. 0.74 per 100 person-months of follow-up). Finally, a third Kaplan-Meier analysis was done on 52 patients that had one eye treated with the ACP procedure and the other eye with the non-ACP procedure. Although the log-rank test showed the statistical significant of this analysis to be borderline, the results again favored the non-ACP group with a lower capsulotomy rate. Multivariate analysis showed very similar results to the above univariate studies. The mean time to capsulotomy was 46 months for the polished group and 70 months for the unpolished group. The severity of cataract (p = 0.46) and the type of haptics (p = 0.86) did not influence the rate of capsulotomy. Plate haptic IOLS had a higher rate of capsulotomy than loop haptic IOLS (p = 0.001). Conclusions: Polishing of the anterior capsule with Shepherd-Rentsch polishers may unexpectedly increase the rate of posterior capsule opacification in eyes with round-edge silicone lenses.

Outcomes of additional posterior to ridge diode laser versus conventional laser anterior to ridge in severe stage 3 retinopathy of prematurity-a randomized control trial

Background:Laser photocoagulation restricted to ablation of the avascular retina has been the conventional but not a completely effective treatment strategy in the management of threshold retinopathy of prematurity(ROP).The purpose of this study was to compare the structural outcomes of additional posterior to ridge diode laser compared to conventional diode laser to avascular retina alone in threshold stage III ROP.Methods:This was a prospective,randomized study involving infants diagnosed with threshold stage III ROP in one or both the eyes.The infants were randomized into control and study groups.Infants under the control group underwent conventional laser to avascular retina alone while infants under the study group received additional two rows of laser posterior to the ridge in the vascular retina.The infants were followed up at 2 weeks,1 month and up to 6 months after the laser procedure.Results:During the study period of 1 year,42 eyes of 24 infants were recruited into this study with 21 eyes in each group.The mean birth weight was 1,310.48±400.92 g in the test group and 1,341.9±396.2 g in the control group.The mean post conceptional age at the time of intervention was 36.43±2.79 weeks in test group and 36.29±2.55 weeks in the control group.At 1-month post laser,19 eyes in the study group showed regression of neovascularization laser compared to 18 eyes in the control group.However at the end of 3 and 6 months post laser,both groups had showed similar rates regression of neovascularization(19 of 21 eyes in both groups).Five eyes in the study group and six in the control group required additional laser treatment.Two eyes in the study group and one eye in the control group developed post laser vitreous hemorrhage.Conclusions:Posterior to ridge laser treatment for severe stage 3 ROP did not show any additional benefit compared to conventional laser.

Femtosecond laser capsulotomy versus manual capsulotomy： a Meta-analysis

AIM：To perform a Meta-analysis on the precision and safety of femtosecond laser（FSL） capsulotomy compared with manual continuous curvilinear capsulotomy（CCC）.· METHODS：We searched PubMed,EMBASE,Web of Science,the Cochrane Library databases,and Clinical Trials.gov that maintained our inclusion criteria.Reference lists of retrieved articles were also reviewed.The effects of morphology of capsulorhexis and the tears of anterior capsule were calculated by using randomeffect models.· RESULTS：We identified 4 randomized and 7nonrandomized studies involving 2941 eyes.The diameter of capsulotomy and the rates of anterior capsule tear showed no statistically difference between FSL group and manual group（MD=0.03;95%CI,-0.03 to0.09,P=0.31）,and（OR=1.40;95%CI,0.28 to 6.97,P=0.68） respectively.In terms of the circularity of capsulotomy,FSL group had a more significant advantage than the manual CCC group（MD=0.09;95%CI,0.05 to 0.12,P〈0.001）.· CONCLUSION：Our Meta-analysis shows that FSL can perform a capsulotomy with more precision and higher reliability than manual CCC.The results in diameter of capsulotomy and the rate of anterior capsule tears was no significant difference between FSL and manual CCC groups.However in terms of circularity,the FSL was superior to the manual procedure.

Pediatric Nd:YAG laser capsulotomy in the operating room: review of 87 cases

AIM: To report a large series of children having Nd:YAG laser capsulotomy in the operating room using the lateral decubitus position. METHODS: Medical records of children who underwent Nd:YAG laser capsulotomy in the operating room at Ann & Robert H. Lurie Children's Hospital of Chicago between September 2008 and April 2017 were reviewed. Induction of general anesthesia and intubation was performed in the supine position after which the patient was placed in lateral decubitus position. The Nd:YAG laser capsulotomy was performed using a standard protocol. At the completion of the procedure, the patient was turned back into the supine position and extubated. RESULTS: This study included 87 eyes of 60 patients. Patient's age ranged from 1 to 18 y(mean 6.4±4.1 y). In most cases(84/87, 97%), the procedure was performed under general anesthesia. In all cases, good focus on the membrane was achieved, and the procedure was performed successfully. There were no intraoperative ocular or anesthesia-related complications. CONCLUSION: When performing Nd:YAG laser capsulotomy in the operating room, the lateral decubitus position allowsan easy and safe approach without the risk of potentially devastating complications that have been associated with the previously described sitting and prone positions.

A randomized controlled trial of peeling and aspiration of Elschnig pearls and neodymium: yttrium-aluminiumgarnet laser capsulotomy

AIM: To compare surgical peeling and aspiration and neodymium yttrium garnet laser capsulotomy for pearl form of posterior capsule opacification(PCO).METHODS: A prospective, randomized, double blind,study was done at Rotary Eye Hospital, Maranda,Palampur, India, Santosh Medical College Hospital,Ghaziabad, India and Laser Eye Clinic, Noida India.Consecutive patients with pearl form of PCO following surgery, phacoemulsification, manual small incision cataract surgery and conventional extracapsular cataract extraction(ECCE) for age related cataract, were randomized to have peeling and aspiration or neodymium yttrium garnet laser capsulotomy. Corrected distance visual acuity(CDVA), intra-operative and postoperative complications were compared.RESULTS: A total of 634 patients participated in the study, and 314(49.5%) patients were randomized to surgical peeling and aspiration group and 320(50.5%) to the Nd:YAG laser group. The mean pre-procedural log MAR CDVA in peeling and neodymium: yttrium-aluminium-garnet(Nd:YAG) laser group was 0.80 ±0.25 and 0.86 ±0.22, respectively. The mean final CDVA in peeling group(0.22 ±0.23) was comparable to Nd:YAG group(0.24 ±0.28; t-test, P =0.240). There was a significant improvement in vision after both the procedures(P 【0.001). A slightly higher percentage of patients in Nd:YAG laser group(283/88.3%) than in peeling group(262/83.4%) had a CDVA of 0.5(20/63) or better at 9mo(P 【0.001). On the contrary, patients havingCDVA worse than 1.00(20/200) was also significantly higher in Nd:YAG laser group as compared to peeling group(25/7.7% vs 15/4.7%, respectively). On application of ANCOVA, there was less than 0.001% risk that PCO thickness and total laser energy had no effect on rate of complications in Nd:YAG laser group and less than 0.001% risk that PCO thickness had no effect on complications in peeling group respectively. Sum of square analysis suggests that in the Nd:YAG laser group,thick PCO had a stronger impact on complications(Fischer test probability, P r 【0.0001) than thin PCO and total laser energy(Fischer test probability, P r 【0.002),respectively; similarly, in peeling group, thick PCO and preoperative vision had a stronger effect on complications than thin PCO, respectively(Fischer test probability, P r 【0.001). The rate of complications like uveitis(P =0.527) and cystoid macular edema(P =0.068),did not differ significantly between both the groups.However, intraocular pressure spikes(P =0.046) and retinal detachment(P【0.001) were significantly higher in Nd:YAG laser group as compared to peeling group.Retinal detachment was more common in patients having degenerative myopia(7/87.5%, P 【0.001). Recurrence of pearls was the most common cause of reduction of vision in the peeling group(24/7.6%, P 【0.001).CONCLUSION: There is no alternative to Nd:YAG laser capsulotomy for fibrous subtype of PCO. For pearl form of PCO, both techniques are comparable with regard to visual outcomes. Nd:YAG laser capsulotomy has a higher incidence of IOP spikes and retinal detachment whereas recurrence of pearls may occur after successful peeling and aspiration. When posterior capsulotomy is needed in patients with retinal degenerations,retinopathies and pre-existing retinal breaks, the clinician should be cautious about increased risks of possible complications of Nd:YAG laser capsulotomy.

Cell death and survival following manual and femtosecond laser-assisted capsulotomy in age-related cataract

AIM： To study molecular and morphological changes in lens epithelial cells following femtosecond laser-assisted and manually performed continuous curvilinear capsulotomy（CCC） in order to get information about these methods regarding their potential role in the induction of development of secondary cataract. METHODS： Anterior lens capsules（ALC） were removed from 40 patients with age-related cataract by manual CCC and by femtosecond laser-assisted capsulotomy（FLAC）. Samples removed by manual CCC were assorted in group 1, FLAC samples were classified in group 2. Morphology of lens epithelial cells was examined with light and electron microscopes. Following capsulotomy, expressions of p53, Bcl-2 and cyclin D1 genes were analyzed with reverse transcriptase polymerase chain reaction. Immunohistochemistry was used to detect the pro-apoptotic p53 in the epithelial cells. RESULTS： Light and electron microscopic examination showed that ALC of group 1 contained more degenerating cells following manual CCC than after FLAC. The expression level of p53 was higher after manual than laser-assisted surgery. Immunocytochemistry indicated significantly higher number of cells containing p53 protein in the manual CCC group than following FLAC. Bcl-2 and cyclin D1 gene expression levels were slightly lower following manual CCC than after FLAC, but the difference was not significant. CONCLUSION： Manually removed ALC shows slightly, but not significantly larger damage due to the mechanical stretching and pulling of the capsule than those removed using FLAC.

Featuring the Nd:YAG laser capsulotomy in the operating room

Dear Editor,We read with interest the article of Kinori et al[1]titled’Pediatric Nd:YAG laser capsulotomy in the operating room:review of 87 cases’.Facilities for laser capsulotomy under general anesthesia are essential for young children and uncooperative patients undergoing cataract surgery.

Cumulative probability and risk analysis for Nd:YAG laser capsulotomy

AIM: To estimate the cumulative probability of Nd:YAG capsulotomy at a teaching institution and evaluate secondary risk factors.METHODS: The records of all patients who underwent phacoemulsification with intraocular lens(IOL) placement between 2005-2010 were retrospectively reviewed. The cumulative probability of Nd:YAG capsulotomy(capsulotomy) was calculated using KaplanMeier survival analysis and secondary risk factors were evaluated using the Cox proportional hazards regression model. RESULTS: One thousand three hundred and fifty four charts were reviewed. A total of 70 capsulotomies wereperformed. The mean follow-up was 19.4 mo(standard deviation 17 mo). The cumulative probability of capsulotomy was 4% at 1 year, 5% at 2 year, and 9% at 3 year. Multivariate analysis demonstrated an increased risk with younger age(HR = 1.03, CI 1.01-1.05, P = 0.007), placement of sulcus IOL(HR = 2.57, CI 1.32-4.99, P = 0.005), ocular trauma(HR = 2.34, CI 1.13-4.83, P = 0.02), and phacoemulsification by a more experienced surgeon(HR = 4.32, CI 1.89-9.87, P = 0.001).CONCLUSION: Cumulative probability of capsulotomy was lower than previously reported. Posterior capsule opacification was strongly associated with younger age and factors associated with high-risk cataract surgery. Surgeon awareness to the risk factors that correlate with posterior capsulotomy may allow for more thorough pre-operative disclosure and enhance patient satisfaction.

Rescue with intravitreal bevacizumab in aggressive posterior retinopathy of prematurity poorly responsive to laser treatment

Successful management of a case of aggressive posterior retinopathy of prematurity(APROP)poorly responsive to laser therapy with intravitreal bevacizumab(IVB)is discussed.IVB is useful as rescue therapy in such cases,if given within the correct window period post laser therapy.

Long term changes of posterior corneal elevation after myopic laser in situ keratomileusis

Background: Corneal ectasia is a serious complication after laser in situ keratomileusis(LASIK). Ideally, patients at risk of ectasia should be identified prior to laser as unsuitable for LASIK, however, at present, there is no absolute test, system, or marker that can unequivocally identify patients at risk of developing ectasia. It has been suggested that changes in the forward protrusion of the posterior cornea or posterior corneal elevation(PCE) may be a key to the early detection of ectasia after LASIK. The purpose of this study was to examine the long term changes of the PCE after myopic LASIK using the ORBSCAN~ IIz(Bausch & Lomb, Rochester, USA) and to evaluate the contributory preoperative factors to PCE changes.Methods: This was a retrospective longitudinal case series. Forty-two eyes of 23 consecutive myopic patients who underwent uneventful LASIK surgery 6 years ago were recalled for a postoperative follow-up examination using the ORBSCAN~ IIz to determine the elevation changes to the posterior corneal surface from the preoperative measurements. A forward shift of the posterior surface was given a negative value. Correlation analyses and forward stepwise regression analyses were performed to evaluate the effect of each of the preoperative parameters on the changes in PCE. Statistical and graphical analyses were performed.Results: There was no statistical difference between the mean best-fit sphere(BFS) pre-LASIK and 6 years postop(P=0.25). Forty-two post-LASIK eyes had a mean posterior displacement of -9.38±9.84 μm(range, 12 to-31 μm) 6 years after LASIK. Forward stepwise multiple linear regression analysis indicated that the ablation spherical equivalent(ASE) was the only indicator of the forward shift of the posterior cornea after LASIK.Conclusions: The present study identified a significant forward shift of the posterior cornea 6 years after LASIK. The ASE was the most significant prognostic determinant for forward protrusion of the posterior cornea after LASIK.

Early results of circularity and centration of capsulotomy prepared by three different methods

AIM:To compare the difference of capsulotomy produced by precision pulse capsulotomy(PPC),manual(M-CCC),and femtosecond laser assisted capsulotomy(FLAC)in relation to intraocular lens(IOL)centration,circularity and its effect on visual outcomes.METHODS:Prospective,non-randomized comparative study conducted at LV Prasad Eye Institute,Hyderabad,India.Sixty eyes of 52 patients were grouped into 3(FLAC,PPC and M-CCC)based on capsulotomy techniques used.Twenty consecutive eyes with uneventful phacoemulsification and with no comorbidities affecting the capsulotomy or visual outcome were included in each group.The main outcome measure was IOL centration in relation to capsulotomy and pupil.Secondary outcome measures were post-operative visual acuity,manifest refraction and aberration profile between groups.RESULTS:At 5 wk the visual,refractive outcomes and endothelial cell density were comparable between the 3 groups.The median circularity index of FLAC was statistically significantly different to M-CCC or PPC(1-10)groups(P<0.01)but PPC(11-20)was comparable to FLAC.Decentration of IOL center in relation to capsulotomy was seen only between the PPC(1-10)group and FLAC group(P=0.02).The IOL was well centered in relation to the pupil in all the groups(P=0.46).The quality of vision parameters like the higher order aberrations,spherical aberration,coma,trefoil,modular transfer function,and Strehl ratio were comparable between the groups.CONCLUSION:Our study shows that despite differences in the morphology of capsulotomy produced by PPC,M-CCC,FLAC a well-centered IOL can be achieved.The measured capsular morphology parameters do not affect visual outcomes.

Effect of four different intraocular lenses on posterior capsule opacification

AIM: To evaluate the impact of 4 different intraocular lenses(IOLs) on posterior capsule opacification(PCO) by comparing the neodymium: yttrium-aluminum-garnet(Nd:YAG) laser capsulotomy rates.METHODS: This retrospective study included 4970 eyes of 4013 cataract patients who underwent phacoemulsification and IOL implantation between January 2000 and January 2008 by the same surgeon at one clinic. Four different IOLs were assessed. The outcome parameter was the incidence of Nd:YAG laser posterior capsulotomies.· RESULTS: An Nd:YAG laser posterior capsulotomy was performed in 153(3.07%) of the 4970 eyes. The mean follow-up time was 84 mo for all of the IOL groups. The percentage of eyes developing PCO was significantly greater for the acrylic hydrophilic IOLs than for the hydrophobic IOLs, although eyes with acrylic hydrophilic IOLs did not require Nd:YAG laser capsulotomy as soon as eyes with acrylic hydrophobic IOLs. There was no difference between the long-term PCO rates when 1-and 3-piece acrylic hydrophobic IOLs were compared or when IOLs made of the same material but with different haptic angles were compared.· CONCLUSION: In this study, eyes with acrylic hydrophilic IOLs were more likely to develop PCO than those with acrylic hydrophobic IOLs. The lens design(1-piece versus 3-piece and varying haptic angles) did not affect the PCO rate.

Hydrophobic versus hydrophilic acrylic intraocular lens on posterior capsule opacification: a Meta-analysis

AIM: To conduct a Meta-analysis pooling randomized controlled trials(RCTs) to compare hydrophobic with hydrophilic acrylic intraocular lenses in terms of posterior capsule opacification(PCO) development.METHODS: Electronic databases including PubMed,Embase, and the Cochrane Library were queried from their starting till January 2020. RCTs investigating the impact of hydrophobic versus hydrophilic acrylic intraocular lenses on PCO were considered eligible in this study. The pooled effect estimates were calculated using the random-effects model.RESULTS: Thirteen RCTs comprising of 939 patients(1263 eyes) were covered in this study. Patients with hydrophobic acrylic intraocular lenses had a lower PCO score than those with a hydrophilic acrylic intraocular lenses [standard mean difference:-1.80;95% confidence interval(CI):-2.62 to-0.98;P<0.001]. Moreover, the frequency of neodymium-doped yttrium aluminum garnet(Nd:YAG)capsulotomy in patients with hydrophobic acrylic intraocular lenses was significantly lower than patients with hydrophilic acrylic intraocular lenses(relative risk: 0.38;95%CI: 0.20-0.71;P=0.003).CONCLUSION: These findings suggest that hydrophobic acrylic intraocular lenses are superior to hydrophilic acrylic intraocular lenses in patients after cataract surgery due to lower PCO score and reduced Nd:YAG capsulotomy. While similar studies are conducted by other researchers, the present study conducted subgroup analyses that show superior results with hydrophobic lenses in trials conducted in western countries.

Intervention of laser periphery iridectomy to posterior iris bowing in high myopic eyes

Background For some high myopic patients with posterior iris bowing, laser periphery iridectomy should be performed pre-operation to prevent pupil block glaucoma if these patients would have phakic intraocular lens implantation to correct high myopia. So we had the opportunity to analysis the influence of laser iridectomy on posterior iris bowing. Methods Eighteen high myopic patients with posterior iris bowing （11 males and 7 females） were involved in the study in Beijing Tongren Eye Center from March 2008 to July 2008. Phakic intraocular lens were implanted to correct their ametropia. The mean age was （32＋6） years （range, 25-40 years）. The center anterior chamber depth, the pupil diameter, the posterior iris bowing depth and the anterior chamber angle were measured with anterior segment coherence tomography （AS-OCT） under the normal condition, myosis condition induced by 2% pilocarpine, laser periphery iridectomy after myosis, and 2% pilocarpine eluting condition respectively. Results There was no significant difference of center anterior chamber depth under the four conditions （P=0.512）. The pupil constricted after pilocarpine （P=0.001）. After＇ laser iridectomy performed and pilocarpine eluted, posterior iris bowing depth reduced more than that in normal condition （P=0.003）. The anterior chamber angle reduced significantly after laser periphery iridectomy and pilocarpine eluted （P=0.012）. Conclusion Laser periphery iridectomy can reduce the posterior iris bowing, which might be due to the change in aqueous circulate pathway.

Long-term efficacy and safety of YAG laser vitreolysis for vision degrading myodesopsia

AIM:To assess the long-term efficacy and safety of yttrium-aluminum garnet(YAG)laser vitreolysis for vision degrading myodesopsia(VDM)caused by posterior vitreous detachment(PVD).METHODS:This retrospective study reviewed VDM patients of PVD type undergoing YAG laser vitreolysis.The baseline demographic information,the patterns of floaters,the number of floaters,and the subjective improvement of floater sympotoms(ranging from 0 to 100%)from medical records were collected.Significant improvement was defined as a relief of floater symptoms of≥50%at the final visit.The long-term efficacy and safety of YAG laser vitreolysis were analyzed.The risk factors linked to significant improvement of floater symptoms were defined using univariate and multivariate logistic regression analyses.RESULTS:The final analysis included 221 patients with VDM.The mean age of patients was 61.08±7.74y,and the mean length of follow-up was 21.38±5.61mo.Totally 57.01%of patients experienced a significant improvement in their floater symptoms after YAG laser therapy,and none of them developed delayed retinal abnormalities such as retinal tears or detachments.Age(OR=1.049,95%CI=1.007-1.092,P=0.021)was identified as a significant risk factor for significant improvement in VDM.CONCLUSION:YAG laser vitreolysis is an effective and secure treatment for PVD-type VDM,and patients of advanced age are more likely to get favorable outcomes.

Nasopharyngeal Obstruction: A Rare Post Laser Assisted Tonsillectomy Complication

Tonsillectomy once was a most common ENT procedure, being referred in past as the “bread and butter of otorhinolaryngologists” though not so commonly performed these days. The usual complications of this procedure have been haemorrhage-primary/reactionary/secondary, infection, tonsillar bed structures injury, and even death. With the advent of newer technologies like lasers, microdebriders, coblators, harmonic scalpel, radiofrequency, newer complications also arise. This case report focuses on one such complication of laser assisted tonsillectomy, not much spoken of in books.