Foldable Intraocular Lens Implantation Research Articles

Reducing angiographic cystoid macular edema and blood–aqueous barrier disruption after small-incision phacoemulsification and foldable intraocular lens implantation: Multicenter prospective randomized comparison of topical diclofenac 0.1% and betamethasone 0.1%

To compare the effectiveness of a topical nonsteroidal drug (diclofenac 0.1%) and a topical steroidal drug (betamethasone 0.1%) in preventing cystoid macular edema (CME) and blood-aqueous barrier (BAB) disruption after small-incision cataract surgery and foldable intraocular lens (IOL) implantation. Shohzankai Medical Foundation Miyake Eye Hospital, Tokyo, Japan. This multicenter interventional double-masked randomized study comprised 142 patients having phacoemulsification and foldable IOL implantation. Seventy-one patients were randomized to receive diclofenac eyedrops and 71, betamethasone eyedrops for 8 weeks postoperatively. The incidence and severity of CME were evaluated by fluorescein angiography. Blood-aqueous barrier disruption was determined by laser flare-cell photometry. Of the patients, 63 were men and 79 were women. Five weeks after surgery, the incidence of fluorescein angiographic CME was lower in the diclofenac group (18.8%) than in the betamethasone group (58.0%) (P<.001). At 1 and 2 weeks, the amount of anterior chamber flare was statistically significantly less in the diclofenac group than in the betamethasone group (P<.05). At 8 weeks, intraocular pressure was statistically significantly higher in the betamethasone group (P = .0003). Diclofenac was more effective than betamethasone in preventing angiographic CME and BAB disruption after small-incision cataract surgery. Thus, nonsteroidal antiinflammatory agents should be considered for routine treatment of eyes having cataract surgery.

The Effect of Topical Diclofenac on Choroidal Blood Flow in Early Postoperative Pseudophakias with Regard to Cystoid Macular Edema Formation

To study the chronological change in choroidal blood flow (ChBFlow), disruption of the blood-aqueous barrier, and incidence of cystoid macular edema (CME) in early postoperative pseudophakic eyes, as well as the effect of nonsteroidal anti-inflammatory drug (NSAID) eye drops on these phenomena. Fifty patients who underwent phacoemulsification and foldable intraocular lens (IOL) implantation were randomized to receive either topical diclofenac or fluorometholone for 5 postoperative weeks. An additional 20 subjects, with long-standing pseudophakia served as the control. The blood-aqueous barrier was examined by laser flarimetry and choroidal blood velocity (ChBVel), volume (ChBVol), and ChBFlow by laser Doppler flowmetry (LDF) at 2 days and 1, 2, and 5 weeks after surgery. The incidence and severity of CME were evaluated by fluorescein angiography at 2 and 5 weeks after surgery. Compared with patients taking diclofenac, those receiving fluorometholone showed significantly reduced ChBVol at 2 weeks (0.38 +/- 0.08 vs. 0.32 +/- 0.07, P = 0.022) and ChBFlow at 1 (11.01 +/- 1.74 vs. 9.35 +/- 1.51, P = 0.003) and 2 (11.15 +/- 1.43 vs. 8.47 +/- 1.27, P = 0.000) weeks after surgery, as well as a significantly elevated amount of anterior flare at 1 (8.9 +/- 2.2 vs. 24.4 +/- 18.9, P = 0.001) and 2 (9.2 +/- 3.5 vs. 16.7 +/- 12.3, P = 0.025) weeks after surgery. The ChBVol and ChBFlow in the fluorometholone group, however, returned to normal and was not different from the diclofenac group at 5 weeks after surgery. The incidence of fluorescein angiographic CME trended to be higher (P = 0.08) at 2 weeks and was significantly higher (P = 0.001) at 5 weeks after surgery in eyes with fluoromethalone than with diclofenac. Reduction of ChBFlow, disruption of the blood-aqueous barrier, and incidence of CME in early postsurgical pseudophakic eyes were more effectively prevented chronologically in eyes treated with diclofenac than in those treated with fluorometholone.

Unusual sequel to a known complication

A 76-year-old man underwent cataract surgery with implantation of an acrylic foldable intraocular lens by standard phacoemulsification technique. The preoperative and immediate postoperative period was uneventful. His postoperative visual acuity...

Clinical study on the management of angle-closure glaucoma by phacoemulsification with foldable posterior chamber intraocular lens implantation

目的 评价透明角膜切口白内障晶状体超声乳化吸出后房人工晶状体植入术治疗原发性闭角型青光眼合并白内障的疗效.方法 回顾性分析闭角型青光眼伴白内障14例(27眼).单纯行透明角膜切口白内障晶状体超声乳化吸出联合后房型人工晶状体植入术,术后随访8～20个月.结果 所有患者术中术后无严重并发症,术后视力较术前明显提高,术后平均眼压(12.64±3.37)mmHg与术前用药后平均眼压(16.72±4.26)mmHg相比差异有统计学意义(配对t检验,P＜0.01),周边前房较术前明显加深,前房角均重新开放或部分开放增宽.结论 单纯透明角膜切口白内障晶状体超声乳化吸出后房型折叠人工晶状体植入术,可有效治疗合并白内障的闭角型青光眼。

Astigmatism after superonasal and superotemporal clear corneal incisions in phacoemulsification

To determine the astigmatism outcomes after cataract surgery performed using superonasal and superotemporal clear corneal incisions. Department of Ophthalmology, Kartal Training and Research Hospital, Istanbul, Turkey. This prospective study includes consecutive 45 eyes of 34 patients having phacoemulsification with implantation of foldable acrylic intraocular lens through a corneal tunnel incision between January and April 2004. The right eye always had a superotemporal incision while the left eye a superonasal incision. Astigmatism was measured by keratometry readings before surgery and 3rd, 15th, and 45th days postoperatively. The surgically induced astigmatism (SIA) was calculated by the vector analysis using the Holladay-Cravy-Koch method at 3rd day, 2nd and 6th weeks postoperatively. The mean preoperative astigmatism was 0.74 +/- 0.45 diopter (D) in the temporal incision group and 0.69 +/- 0.39 D in the nasal incision group. Fifty-eight percent of eyes had against-the-rule (ATR) astigmatism, 26% had with-the-rule (WTR) astigmatism, and 16% were astigmatically neutral. At 6 weeks, 46% of eyes had ATR astigmatism and 35% had WTR astigmatism. The mean total astigmatism was lower in the temporal incision group than in the nasal incision group at all successive examinations postoperatively. Although the total astigmatism decreased at 6 weeks in both groups, temporal incisions yielded less total and surgically induced astigmatism (P < .05). Cataract surgery using superotemporal incision induced significantly less SIA in the early postoperative period.

Management of large traumatic zonular dialysis with phacoemulsification and IOL implantation using the capsular tension ring

To report our results and to evaluate the longterm effect of capsular tension ring (CTR) insertion in eyes with large traumatic zonular dialysis that underwent phacoemulsification with posterior chamber (PC) intraocular lens (IOL) implantation. This prospective study included 17 eyes of 17 consecutive patients with cataract and large traumatic zonular dialysis (range 80-160 degrees determined pre-or intraoperatively). After insertion of a CTR, phacoemulsification with foldable acrylic PC IOL implantation was performed. Posterior capsule rupture, vitreous loss, best corrected visual acuity (BCVA), intraocular pressure (IOP) in the pre- and postoperative periods and postoperative IOL decentration were recorded. The mean follow-up period was 25.9 months (range 15-35 months). Capsule collapse did not occur in any eye with a CTR. Postoperatively, four eyes developed raised IOP that responded well to medical therapy. An improvement in BCVA was observed in all eyes except one because of co-existing fundus pathology. No IOL was found to be decentrated at the end of the follow-up period, apart from one eye in which the PC IOL was dislocated due to a postoperative trauma, in which an anterior chamber IOL was implanted. In cases of cataract associated with large traumatic zonular dialysis, implanting a CTR before or during phacoemulsification with an in-the-bag PC IOL is relatively safe technique with a high success rate. The CTR was found to be efficient in preventing IOL decentration in eyes with traumatic zonular deficiency.

Topical plus subconjunctival anaesthesia: foldable intraocular lens implantation in eyes without capsule support through a self‐sealing incision

To evaluate the clinical outcomes of topical plus subconjunctival anaesthesia for secondary implantation of foldable intraocular lens (IOL) (Ophtec PC 425Y) in eyes without capsule support through a self-sealing incision. We reviewed the medical records of 22 patients (22 eyes) who received topical plus subconjunctival anaesthesia for scleral fixation of a foldable IOL through small incision. The scleral incision technique was used for IOL scleral fixation. Twelve eyes had traumatic cataract, seven had postphacoemulsification complications and three were aphakic. We studied visual outcome, intraoperative complications and perioperative pain. Autorefractometry and keratometry measurements and central endothelial cell counts were evaluated 1 day preoperatively and 4 months postoperatively. The level of intraoperative pain was scored on a scale of 1-10, where 1 = no pain and 10 = severe pain. Nineteen patients (86%) tolerated the procedure well, giving pain scores of 1-3, and none required supplemental anaesthesia. The mean age of the patients was 60 years. The postoperative best-corrected visual acuity (BCVA) ranged between 20/100 and 20/25. Four months postoperatively, the mean myopic shift by autorefractometry was -1.25 dioptre (D) and the mean postoperative astigmatism was 1.75 D. The mean central corneal endothelial loss at 4 months was 12.24% (range 4.5-17.2%). Five microscopic hyphaema occurred intraoperatively. Four cystoid macular oedema and four peripheral anterior synechia were the only complications, each occurring at the final follow-up. Topical plus subconjunctival anaesthesia and scleral fixation of foldable IOL (Ophtec PC 425Y) was safe, quick, required a small incision, led to favourable visual outcomes and minimized the risk of intraoperative and postoperative complications in eyes without capsule support. However, a long-term study of a large population is required to confirm these findings.

Implantation of foldable intraocular lens in eyes without lens capsule support

目的 探讨无晶状体囊眼的折叠式人工晶状体植入的可行性和有效性.方法 28例无晶状体囊眼,经3.2mm角膜缘切口或透明角膜切口,植入Alcon单片式折叠式人工晶状体,双襻用10-0聚丙烯缝线缝合固定于睫状沟,观察术中植人情况和术后视力、角膜、眼内炎反应症及人工晶状体位置等情况.结果 所有病例均顺利植入人工晶状体,1例术中出现前房积血.术后随访3～18月,视力均有不同程度提高,人工晶状体位置正,无严重术后并发症发生.结论 单片式折叠人工晶状体双襻缝线固定植入治疗无晶状体囊眼是可行和有效的,长期的并发症有待进一步观察。

Comparison of Sulcus Implantation of Single-Piece Hydrophilic Foldable Acrylic and Polymethylmethacrylate Intraocular Lenses in Eyes with Posterior Capsule Tear during Phacoemulsification Surgery

To compare the results of sulcus implantation of acrylic and poly(methylmethacrylate) (PMMA) intraocular lens (IOL) in eyes with posterior capsule tear during phacoemulsification surgery. In all eyes a posterior capsule tear developed during phacoemulsification surgery and an IOL to the ciliary sulcus was implanted primarily. A total of 89 eyes of 88 patients received hydrophilic foldable acrylic IOL (acrylic group). A total of 72 eyes of 72 patients received PMMA IOL (PMMA group). The mean age was 67.1 years and 68.1 years and postoperative follow-up period was 19.2 months and 17.9 months in acrylic and PMMA groups, respectively. Temporary corneal edema appeared in 33 eyes and 26 eyes, elevation of intraocular pressure in 17 eyes and 12 eyes, anterior chamber inflammatory reaction in 5 eyes and 5 eyes, clinical cystoid macular edema in 7 eyes and 12 eyes, and decentered IOL in 4 eyes and 3 eyes in acrylic and PMMA groups, respectively. Late postoperative endophthalmitis developed in two eyes of the PMMA group. Rhegmatogenous retinal detachment developed in one eye in each group. Final best-corrected visual acuities were 5/10 and above in 73 eyes (82.02%) in the acrylic group and 5/10 and above in 42 eyes (58.33%) in the PMMA group. Postoperative final induced astigmatism was 0.5+/-0.5 D (SD) in the acrylic group and 1.11+/-0.65 D (SD) in the PMMA group (p=0.0001) (independent samples t-test). Increased astigmatism is more frequently seen in the PMMA group. The implantation of foldable acrylic IOL in the sulcus after posterior capsule tear maintains the advantages of small incision surgery.

Vitrectomy combined with phacoemulsification and intraocular lens implantation for treatment of proliferative diabetic retinopathy

To determine clinical outcomes of vitrectomy and silicone oil tamponade combined with phacoemulsification and foldable intraocular lens (IOL) implantation for the treatment of severe proliferative diabetic retinopathy (PDR). Fifty-three patients (57 eyes) with proliferative diabetic retinopathy were included in this study. All patients had tractional or tractional-rhegmatogenous retinal detachment. These patients were divided into combined surgery group and vitrectomy group. Thirty-three patients (33 eyes) of combined surgery group underwent vitreoretinal surgery and silicone oil tamponade combined with phacoemulsification and foldable intraocular implantation. Twenty patients (24 eyes) of vitrectomy group underwent vitreoretinal surgery and silicone oil tamponade only. The postoperative rates of retinal reattachment and complications were analyzed. Rates of retinal reattachment in combined surgery group was 87.9% vs. 83.3% for vitrectomy groups. The difference in rates of retinal reattachment was not statistically significant between these 2 groups (P > 0.05). Rates of visual acuity better than 0.1 in combined surgery group was 60.6% vs. 33.3% in vitrectomy group 6 month after operation. The difference in rates of postoperative iris neovascularization was not statistically significant between these 2 groups (P > 0.05). Combined vitreoretinal surgery and phacoemulsification with intraocular lens implantation is safe and effective in treating severe proliferative diabetic retinopathy. Combined surgery may prevent a second operation for post vitrectomy cataract, allowing earlier visual rehabilitation.

Paediatric pseudophakia: analysis of intraocular lens power and myopic shift

At the Alberta Children's Hospital, the authors have been performing paediatric cataract extraction with intraocular lens (IOL) implant for over 10 years. The authors examined the amount of myopic shift that occurs in various age groups and cataract types, in order to evaluate the success of predicting the appropriate power of IOL to implant. This study is a retrospective review children undergoing small incision posterior chamber foldable IOL implantation between age 1 month and 18 years, from 1995 to 2005. 163 eyes of 126 patients underwent surgery. All patients were followed for a minimum of 6 months postoperatively. The children were divided into four groups at time of surgery: Group A: 1-24 months, Group B: 25-48 months, Group C: 49-84 months, Group D: 85 months-18 years. The mean target refraction for the groups were: Group A: +6.37 D, Group B: +4.66 D, Group C: +1.95 D, and Group D: +0.97 D. Children under 4 years experienced the most myopic shift and the largest mean rate of refractive change per year. Mean change Group A: -5.43 D, Group B: -4.16 D, Group C: -1.58 D, Group D: -0.71 D. Eighty-nine per cent of patients with unilateral cataracts had a postoperative refraction within 3.00 D of the fellow eye at last follow-up visit (mean=3.16 years). The rate of myopic shift is high in children under age 4 years at time of surgery, shifting as much as -12.00 D. The mean postoperative target refraction should probably be increased from previous literature recommendations. The patient's age at time of cataract surgery and the refractive power of fellow eye are all factors to consider when deciding what power IOL to surgically implant in a paediatric patient.

Relationship between ciliary muscle contraction and the pseudo accommodation after the implantation of foldable intraocular lenses

To investigate the relationship between high frequency component of accommodative microfluctuation (HFC) and the pseudo accommodation after the implantation of foldable intraocular lenses (IOL). With ARK-730A accommodation analyzer we checked HFC in 50 cases (50 eyes) of patients who had good pupil reaction to light and the pupil diameter was 2.0 approximately 3.5 mm approximately. Three months after the implantation of foldable IOL, the relationship among ciliary muscle accommodative microfluctuation, IOL movement and pseudo accommodation was analyzed. There was positive correlation between ciliary muscle accommodative microfluctuation and IOL movement (r = 0.702, P < 0.01), between IOL movement and pseudo accommodation (r = 0.861, P < 0.01), and between ciliary muscle accommodative microfluctuation and pseudo accommodation (r = 0.915, P < 0.01). Pseudo accommodation was greater in patients who showed more ciliary muscle accommodative microfluctuation and IOL movement. HFC induces IOL movement, and it is one of the most important reasons for pseudo accommodation after foldable IOL implantation.

Evaluation of Macular Changes After Uncomplicated Phacoemulsification Surgery by Optical Coherence Tomography

Purpose: To evaluate the effect of uncomplicated phacoemulsification surgery on macula by optical coherence tomography (OCT). Methods: A total of 110 eyes of 102 patients who underwent uncomplicated phacoemulsification and foldable intraocular lens implantation at Beyoglu Eye Research and Training Hospital between February and March 2005 and who were without any systemic disease, fundus or other ocular pathology were included. Postoperatively, topical prednisolone acetate (6× 1) and ofloxacine (5× 1) was started, and by decreasing the dosage progressively, treatment was continued for 6 weeks. Full ophthalmologic and OCT examinations were done preoperatively and at the postoperative 1st day, 1st week, 1st, 3rd, and 6th months. Mean retinal thicknesses, volumetric analyses at central fovea, superior, inferior, temporal, and nasal macular quadrants, and thinnest foveal retinal thicknesses were recorded. Preoperative and postoperative measurements were analyzed statistically by using ANOVA test, paired samples t-test with Bonferroni correction, and Pearson's correlation test. Results: The mean central foveal retinal thickness was preoperatively 202.4 ± 25.9 μ m, postoperatively 200.4 ± 26.1 μ m at 1st day (p = 0.29), 208.4 ± 27.6 μ m at 1st week (p = 0.29), 226.2 ± 54.9 μ m at 1st month, 215.2 ± 24.0 μ m at 3rd month, 213.5 ± 29.4 μ m at 6th month (p < 0.001). Perifoveal macular thicknesses at superior, inferior, temporal, and nasal quadrants were 264.9 ± 28.8 μ m, 266.1 ± 29.5 μ m, 255.0 ± 31.3 μ m, 260.3 ± 34.0 μ m, respectively, preoperatively; 287.9 ± 28.4 μ m, 288.0 ± 26.3 μ m, 286.8 ± 33.1 μ m, 272.0 ± 32.4 μ m, respectively, at postoperative 1st month (p < 0.001). The change in mean central foveal thickness, foveal thinnest retinal thickness, mean perifoveal retinal thickness and volumetric analyses was insignificant at postoperative 1st day (p > 0.05), and significant at 1st week, 1st, 3rd, and 6th months (p < 0.05 for all measurements). Conclusions: Statistically significant increase in macular thickness was detected at postoperative early periods, after the 1st week after uncomplicated cataract operation. The increase in macular thickness starts from parafoveal regions. Longer follow-up of patients is required for the macular consequences, and different treatment protocols should be studied in a randomized controlled fashion.

Pain Induced by Phacoemulsification Performed by Residents Using Topical Anesthesia

To evaluate patient-reported pain induced by phacoemulsification performed by residents using topical anesthesia. This prospective study comprised 81 eyes of 76 consecutive patients having phacoemulsification under topical anesthesia. Surgery was performed by an experienced surgeon (group 1; n=41 eyes) or by two residents (group 2; n=40 eyes). No sedation or intracameral anesthesia was used in either group. Eighty eyes had clear corneal phacoemulsification with foldable acrylic posterior chamber intraocular lens implantation. Patients were asked postoperatively to grade the pain they experienced during the procedure using a visual analog pain scale from 0 to 10. The median pain score for the overall pain was 1.59 +/- 1.43 (range: 0 to 6) in group 1 and 1.95 +/- 1.64 (range: 0 to 7) in group 2 (P = .291). The mean pain score for the maximum pain perceived was 2.39 +/- 1.86 (range: 0 to 7) in group 1 and 2.53 +/- 1.67 (range: 0 to 7) in group 2 (P = .734). There was no significant correlation between the duration of surgery and the overall pain score (r = 0.102, P = .365). Topical anesthesia had sufficient analgesic effects in selected patients undergoing phacoemulsification cataract surgery by resident surgeons. The pain felt during the operation was low and tolerable.

Factors influencing refractive outcomes after combined phacoemulsification and pars plana vitrectomy: Results of a prospective study

To evaluate the factors influencing the refractive outcomes of combined phacoemulsification, foldable intraocular lens (IOL) implantation, and pars plana vitrectomy (PPV). Department of Ophthalmology, Seoul National University Hospital, Seoul, Korea. One hundred fifty-four consecutive patients who had combined phacoemulsification, IOL implantation, and PPV between September 2001 and August 2004 were enrolled in a prospective study. Refractive, keratometric, and axial length measurements were performed preoperatively and 4 months postoperatively. The factors influencing the postoperative refractive outcomes were analyzed. The mean refractive prediction error (ie, actual minus predicted spherical equivalent [SE]) was -0.06 diopters (D) +/- 0.75 (SD). In long eyes (preoperative axial length more than 24.5 mm), the mean predicted SE and actual SE were -0.81 +/- 0.76 D and -1.24 +/- 0.79 D, respectively; the difference was significantly different (P = .001, paired t test). Patients with a preoperative visual acuity worse than 5/200 and those with preoperative foveal detachment had a significant postoperative myopic shift (P = 0.024 and P = 0.002, respectively; paired t test). Postoperative refractive error was not influenced by the intraocular air or gas tamponade during surgery (P = 0.336, paired t test). The combined surgery included a small biometric error that was within the tolerable range in most cases. However, myopic shifts developed in patients with long axial lengths, poor preoperative visual acuity, and the preoperative presence of foveal detachment.

Cystoid macular edema after phacoemulsification: risk factors and effect on visual acuity

Background: To determine the incidence and risk factors for cystoid macular edema (CME) after phacoemulsification surgery and its effect on visual acuity. Methods: This prospective study evaluated 98 eyes of 98 patients (43 women) with a mean (SD) age of 61.8 (11.3) years. Phacoemulsification was performed with temporal clear corneal incision and implantation of foldable hydrophilic acrylic intraocular lens in the bag. Postoperative visits were on day 1, week 1, and at 1, 3, and 6 months. In addition, at week 10 all patients had fundus fluorescein angiography, and presence of CME was determined. Age, sex, iris colour, pseudoexfoliation, type of cataract, phaco time, status of the posterior vitreous, iris trauma, severity of anterior chamber reaction, and visual acuities were evaluated. Results: No major intraoperative complications occurred. Twenty-five (25.5%) eyes were CME(+), and 73 (74.4%) eyes were CME(−). CME occurred in 70% of patients with iris trauma and 20.5% of patients with no iris trauma. CME was more common in patients who had postoperative anterior chamber inflammation of 2+ or more than in patients with less inflammation (43.2% vs. 11.5%). Complete posterior vitreous detachment had some apparent protective effect against CME development. The mean visual acuities of CME(+) patients were lower than those of CME(−) patients in all postoperative periods. The difference was significant in the third month ( p < 0.05). Interpretation: CME after phacoemulsification was associated with iris trauma and severe postoperative inflammation. Complete posterior vitreous detachment had some apparent protective effect against CME development. CME may be associated with decreased visual acuity.

Scheimpflug measurement of intraocular lens position after piggyback implantation of foldable intraocular lenses in eyes with high hyperopia

To investigate the position of 3-piece foldable intraocular lenses (IOLs) after piggyback implantation for high hyperopia. University Eye Hospital, Johann Wolfgang Goethe University, Frankfurt am Main, Germany. Eight eyes of 5 highly hyperopic patients had phacoemulsification and implantation of 2 foldable IOLs. In 3 eyes, both IOLs were implanted in the capsular bag. In 5 eyes, 1 IOL was placed in the capsular bag and the second IOL in the ciliary sulcus. Intraocular lens optic tilt and decentration, combined thickness of both IOLs, and anterior chamber depth (ACD) were measured postoperatively over a period of 18 months using Scheimpflug photography. All eyes with both IOLs in the capsular bag showed interpseudophakic opacification, with a mean increase in combined IOL thickness of 0.4 mm, a decrease in ACD of 0.3 mm, and a corresponding hyperopic shift of 4.00 diopters. Eyes in which the anterior IOL was placed in the ciliary sulcus showed no changes in refraction or combined IOL thickness. In these eyes, the anterior IOL had a higher mean decentration (0.49 mm +/- 0.20 [SD] after 12 months) than the posterior IOL (0.21 +/- 0.13 mm after 12 months). Piggyback IOL implantation with placement of 2 foldable IOLs in the capsular bag can be followed by a hyperopic shift that may be caused in part by displacement of the IOLs. Placement of the anterior IOL in the ciliary sulcus can lead to higher decentration of this IOL.

Evaluation of Early Corneal Endothelial Cell Loss in Bimanual Microincision Cataract Surgery (MICS) in Comparison with Standard Phacoemulsification

To analyze early corneal endothelial cell loss due to microincision cataract surgery (MICS) in comparison with standard phacoemulsification through the temporal clear corneal incision. The examined group consisted of a nonrandomized, consecutive prospective series of 20 eyes of 20 patients who underwent uneventful microincision cataract surgery. Twenty eyes of 20 patients who underwent standard phacoemulsification with foldable intraocular lens (IOL) implantation served as a reference group. Patients with corneal disorders, contact lens wear, previous intraocular surgery, and a history of ocular trauma were excluded from the study. Patients were examined preoperatively and 10 days postoperatively. The following items were evaluated in this study: corneal endothelial cell density, intraoperative phaco power, effective phaco time, as well as pre- and postoperative visual acuity. Corneal endothelial cell counts were done in the central part of the cornea using a non-contact Topcon SP 2000P specular microscope before and 10 days after the surgery. The measurements were performed in a semiautomated, masked manner. Statistical analysis was done using nonparametric tests (Wilcoxon signed-ranks test and Mann-Whitney U test). All patients in the study underwent uneventful surgery. Best-corrected visual acuity (BCVA) examined 10 days postoperatively in the MICS group was 0.94+/-0.094, whereas in the standard phacoemulsification group it was 0.90+/-0.094. There was no significant difference between BCVA in the two groups (Mann Whitney U two-tailed test: p>0.05). In both groups there was a significant decrease in postoperative endothelial cell densities (ECDs) when compared to preoperative values. Mean postoperative ECDs were 2235+/-418 cells/mm2 in the MICS group and 2079+/-399 cells/mm2 in the standard phacoemulsification group; the difference was not statistically significant (Mann-Whitney U test: p>0.05). Patients in the MICS group lost an average of 9.5% of cells, whereas patients after standard phacoemulsification lost about 7.6% of cells. This difference was statistically insignificant. Microincision cataract surgery induced corneal endothelial cell loss similar to a standard phacoemulsification and allowed excellent visual results in this series of patients. These results support the use of MICS technique for cataract surgery.

Improved accuracy of intraocular lens power calculation with the Zeiss IOLMaster

This study aimed to demonstrate how the level of accuracy in intraocular lens (IOL) power calculation can be improved with optical biometry using partial optical coherence interferometry (PCI) (Zeiss IOLMaster) and current anterior chamber depth (ACD) prediction algorithms. Intraocular lens power in 461 consecutive cataract operations was calculated using both PCI and ultrasound and the accuracy of the results of each technique were compared. To illustrate the importance of ACD prediction per se, predictions were calculated using both a recently published 5-variable method and the Haigis 2-variable method and the results compared. All calculations were optimized in retrospect to account for systematic errors, including IOL constants and other off-set errors. The average absolute IOL prediction error (observed minus expected refraction) was 0.65 dioptres with ultrasound and 0.43 D with PCI using the 5-variable ACD prediction method (p < 0.00001). The number of predictions within +/- 0.5 D, +/- 1.0 D and +/- 2.0 D of the expected outcome was 62.5%, 92.4% and 99.9% with PCI, compared with 45.5%, 77.3% and 98.4% with ultrasound, respectively (p < 0.00001). The 2-variable ACD method resulted in an average error in PCI predictions of 0.46 D, which was significantly higher than the error in the 5-variable method (p < 0.001). The accuracy of IOL power calculation can be significantly improved using calibrated axial length readings obtained with PCI and modern IOL power calculation formulas incorporating the latest generation ACD prediction algorithms.

Bacterial contamination in the anterior chamber after povidone–iodine application and the effect of the lens implantation device

To assess the incidence of anterior chamber bacterial contamination during cataract surgery, and compare results of injector implantation and forceps implantation of foldable intraocular lenses (IOLs). Department of Ophthalmology and Institute of Medical Microbiology, Semmelweis University, Budapest, Hungary. This prospective randomized controlled clinical study comprised 97 eyes of 96 patients. Antibiotic eyedrops were not used; however, povidone-iodine 10% solution was used to prepare the eyebrow and eyelids and povidone-iodine 5% to disinfect the ocular surface. A Steri-Drape (3M) was used to surround the eye. Aqueous fluid samples were aspirated from the anterior chamber at the beginning and the end of surgery. The samples were cultured for 14 days under aerobic and anaerobic conditions simultaneously. Cataract surgery was performed using a sutureless, superotemporal, clear corneal phacoemulsification technique. The IOL was implanted with an injector (n = 47) or a forceps (n = 50), with the instrument randomly selected. The frequency of positive bacterial cultures with each implantation method was compared using the Fisher exact test. Bacteria were found in the conjunctival samples in 21 eyes (21.65%) before povidone-iodine application and in 4 eyes (4.12%) after disinfection. The anterior chamber sample before surgery was culture positive for Staphylococcus epidermidis in 2 eyes and for Micrococcus luteus in 1 eye. After surgery, the culture was positive for S epidermidis in 1 eye (2.15%) in the injector group and 1 eye (2.00%) in the forceps group (P = .74). Neither sample came from an eye that had a positive culture preoperatively. There were no intraoperative complications. In uneventful clear corneal phacoemulsification, meticulous technique can prevent antibiotic use during surgery. No difference in anterior chamber bacterial contamination was found between IOL implantation using an injector or a forceps.