A new model of posterior capsule opacification in rodents

PURPOSE. To describe a new model of posterior capsule opacification (PCO) in rodents METHODS. An extracapsular lens extraction (ECLE), by continuous curvilinear capsulorrhexis and hydrodissection, was performed in 42 consecutive Brown Norway rats. Animals were killed at 0, 6, and 24 hours and 3, 7, and 14 days after surgery. Eyes were enucleated and processed for light microscopy and immunohistochemistry. RESULTS. In 34 (81%) of the animals the operated eye appeared well healed before death, with a clear cornea and a well-formed anterior chamber. In eight (19%) there was no view of anterior segment structures because of hyphema, fibrin, or corneal opacification. PCO was clinically evident 3 days after ECLE and was present in all animals at 2 weeks. Immediately after ECLE, lens epithelial cells (LECs) were present in the inner surface of the anterior capsule and lens bow. Twenty-four hours after surgery, LECs started to migrate toward the center of the posterior capsule. At 3 days, multilayered LECs, some spindle shaped, were present throughout the lens capsule. Capsular wrinkling was apparent. Lens fibers and Soemmering's ring were observed in all animals 14 days after surgery, indicating some degree of cellular differentiation. Activated macrophages were present in greater numbers at 3 and 14 days after surgery (P <0.05), when proliferation and migration of LECs appeared to be greatest, and lens fiber differentiation was evident, respectively. CONCLUSIONS. In rodents PCO occurs after ECLE and is associated with low-grade inflammation, mostly of mononuclear macrophages. Although no intraocular lens implantation was performed, this model appears to be valuable for studying the sequence of events that leads to PCO after cataract surgery and the extracellular matrix cues that promote lens fiber differentiation.

Indications for penetrating keratoplasty and associated procedures, 1989-1995

Purpose. To identify changing trends in indications for penetrating keratoplasty and associated surgical procedures. Methods. Review of charts from all patients who underwent penetrating keratoplasty at Wills Eye Hospital from January 1, 1989 through December 31, 1995. Results. A total of 2,442 corneal transplants were performed in 2,186 patients. The leading indication for penetrating keratoplasty was pseudophakic corneal edema, accounting for 634 cases (26.0%); 54.7% of them were associated with anterior chamber intraocular lenses, 36.4% with posterior chamber intraocular lenses, and 3.1% with iris-fixated intraocular lenses. Regraft (17.8%), Fuchs' dystrophy (15.7%), and keratoconus (13.2%) followed pseudophakic corneal edema in frequency. Cataract extraction, with or without intraocular lens implantation, was combined with penetrating keratoplasty in 439 cases of 1,264 phakic eyes (34.7%). Intraocular lens exchange was performed in 285 of the 634 cases of pseudophakic cornea edema (44.9%). Conclusion. Pseudophakic corneal edema was the leading indication for penetrating keratoplasty, with an increasing number of cases associated with posterior chamber intraocular lenses during the study period (p = 0.001). The number of regrafts steadily increased between 1989 and 1995 (p = 0.001), being the second most common indication for corneal transplantation since 1992.

Surgical technique:Complex glaucoma case requiring molteno drainage tube extension

A 42-year-old man has been under long-term follow-up since he was a child for congenital glaucoma and buphthalmos in both eyes. His left eye best corrected visual acuity (BCVA) was counting fingers, due to end-stage glaucoma. He was on maximal medical therapy with an intraocular pressure (IOP) maintained at mid to low twenties. His right eye, the only seeing eye, had a BCVA of 6/9. This eye had undergone multiple glaucoma laser and surgical procedures, including an initial first Molteno drainage device inserted superonasally that failed in April 2003 due to fibrotic membrane over the tube opening. As a result, he subsequently had a second Molteno drainage device inserted inferotemporally. To further maximize his vision he had an uncomplicated cataract extraction and intraocular lens implant in December 2004, after which he developed postoperative cystoid macular edema and corneal endothelial failure. He underwent a penetrating keratoplasty in the right eye thereafter in March 2007. After approximately a year, the second Molteno device developed drainage tube retraction, which was managed surgically to maintain optimum IOP in the right eye. His right eye vision to date is maintained at 6/12. © 2011 Mustafa and Azuara-Blanco.

The outcome of the functioning filter after subsequent cataract extraction

OBJECTIVE: To evaluate and compare the outcome of functioning filtration surgery followed by cataract surgery with posterior intraocular lens implantation by both phacoemulsification and extracapsular cataract extraction (ECCE) techniques in glaucomatous eyes. PATIENTS AND METHODS: We retrospectively evaluated the clinical course of 77 eyes (68 patients) that after successful trabeculectomy, underwent cataract surgery by either phacoemulsification or ECCE techniques. We determined the frequency of partial and absolute failure following cataract surgery by either phacoemulsification or ECCE in eyes with functioning trabeculectomies. Partial failure of intraocular pressure (IOP), control after cataract extraction was defined as the need for an increased number of antiglaucoma medications or argon laser trabeculoplasty to maintain IOP =21mm Hg. Complete failure of IOP control after cataract surgery was defined as an IOP >21 mm Hg on at least two consecutive measurements one or more weeks apart or the performance of additional filtration surgery. Failure rates were calculated using the Kaplan-Meier actuarial method. Failure rates between phacoemulsification and ECCE subgroups were compared using the log rank test. RESULTS: The probability of partial failure by the third postoperative year after cataract surgery was 39.5% in the phacoemulsification subgroup and 37.3% in the ECCE subgroup. This small difference is not statistically significant (P = 0.48). The probability of complete failure by the fourth postoperative year after cataract surgery was 12.0% in the phacoemulsification subgroup and 12.5% in the ECCE subgroup. This difference is also not statistically significant (P = 0.77). At the 6-month follow-up visit, visual acuity of both groups improved one or more lines in 87.0% of patients, and worsened one or more lines in 3.9% of patients. Sixty-one percent achieved visual acuity of 20/40 or better. The most frequent complication was posterior capsular opacification requiring laser capsulotomy that occurred in 31.2% of patients. CONCLUSION: Cataract extraction by either phacoemulsification or ECCE following trabeculectomy surgery may be associated with a partial loss of the previously functioning filter and the need for more antiglaucoma medications to control IOP.

Surgical checklist for cataract surgery:progress with the initiative by the Royal College of Ophthalmologists to improve patient safety

PurposeThe World Health Organisation (WHO) identified patient safety in surgery as an important public health matter and advised the adoption of a universal peri-operative surgical checklist. An adapted version of the WHO checklist has been mandatory in the National Health Service since 2010. Wrong intraocular lens (IOL) implantation is a particular safety concern in ophthalmology. The Royal College of Ophthalmologists launched a bespoke checklist for cataract surgery in 2010 to reduce the likelihood of preventable errors. We sought to ascertain the use of checklists in cataract surgery in 2012.Patients and methodsA survey of members of the Royal College of Ophthalmologists seeking views on the use of checklists in cataract surgery. Four hundred and sixty-nine completed responses were received (18% response rate).ResultsRespondents worked in England (75%), Scotland (11%), Wales (5%), Northern Ireland (2%), the Republic of Ireland (1%), and overseas (6%). Ninety-four per cent of respondents support the use of a checklist for cataract surgery and 85% say that they always use a checklist before cataract surgery. Sixty-seven per cent of cataract surgeons stated they undertake a pre-operative team brief. Thirty-six per cent use a cataract surgery checklist developed locally, 18% use the college's bespoke cataract surgery checklist, 39% use a generic surgical checklist, and 4% reported that they do not use a checklist.ConclusionNinety-three per cent of cataract surgeons responding to the questionnaire report using a surgical checklist and 67% use a team brief. However, only 54% use a checklist, which addresses the selection of the correct intraocular implant. We recommend wider adoption of checklists, which address risks relevant to cataract surgery, in particular the possibility of selection of an incorrect IOL.Eye advance online publication, 24 May 2013; doi:10.1038/eye.2013.101.

Photosensitisers - the progression from photodynamic therapy to anti-infective surfaces

Introduction: The application of light as a stimulus in pharmaceutical systems and the associated ability to provide precise spatiotemporal control over location, wavelength and intensity, allowing ease of external control independent of environmental conditionals, has led to its increased use. Of particular note is the use of light with photosensitisers.

Areas covered: Photosensitisers are widely used in photodynamic therapy to cause a cidal effect towards cells on irradiation due to the generation of reactive oxygen species. These cidal effects have also been used to treat infectious diseases. The effects and benefits of photosensitisers in the treatment of such conditions are still being developed and further realised, with the design of novel delivery strategies. This review provides an overview of the realisation of the pharmaceutically relevant uses of photosensitisers, both in the context of current research and in terms of current clinical application, and looks to the future direction of research.

Expert opinion: Substantial advances have been and are being made in the use of photosensitisers. Of particular note are their antimicrobial applications, due to absence of resistance that is so frequently associated with conventional treatments. Their potency of action and the ability to immobilise to polymeric supports is opening a wide range of possibilities with great potential for use in healthcare infection prevention strategies.

Phacoemulsification combined with posterior capsulorhexis and anterior vitrectomy in the management of malignant glaucoma in phakic eyes

Purpose: To describe sequential phacoemulsification-intraocular lens (IOL) implantation-posterior capsulorhexis-anterior vitrectomy in the management of phakic malignant glaucoma. Methods: Twenty consecutive patients (25 eyes) with phakic malignant glaucoma were enrolled at the Zhongshan Ophthalmic Center, Sun Yat-sen University. All patients underwent phacoemulsification, IOL implantation and posterior capsulorhexis together with anterior vitrectomy via a clear corneal paracentesis. Visual acuity, intraocular pressure (IOP), anterior chamber depth (ACD), surgical complications and medications required after the surgery were recorded. Results: After surgery, the mean LogMAR visual acuity and ACD increased significantly (visual acuity from -1.56 ± 1.17 to -0.54 ± 0.81, p < 0.001; ACD from 0.367 ± 0.397 mm to 2.390 ± 0.575 mm, p < 0.001), and mean IOP decreased significantly (from 39.6 ± 10.6 mm Hg to 14.5 ± 4.1 mmHg, p < 0.001). No serious perioperative complications occurred, and only five eyes required topical glaucoma medications after surgery. Conclusion: Combined phacoemulsification-IOL implantation-posterior capsulorhexis-anterior vitrectomy surgery is a safe and effective method for treating patients with phakic malignant glaucoma. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

Visual outcomes of cataract surgery performed by supervised novice surgeons during training in rural China

To assess the outcomes of cataract surgery performed by novice surgeons during training in a rural programme. Design: Retrospective study. Participants: Three hundred thirty-four patients operated by two trainees under supervision at rural Chinese county hospitals. Methods: Two trainees performed surgeries under supervision. Visual acuity, refraction and examinations were carried out 3 months postoperatively. Main Outcome Measures: Postoperative uncorrected visual acuity, pinhole visual acuity, causes of visual impairment (postoperative uncorrected visual acuity<6/18) Results: Among 518 operated patients, 426 (82.2%) could be contacted and 334 (64.4% of operated patients) completed the examinations. The mean age was 74.1±8.8 years and 62.9% were women. Postoperative uncorrected visual acuity was available in 372 eyes. Among them, uncorrected visual acuity was ≥6/18 in 278 eyes (74.7%) and <6/60 in 60 eyes (16.1%), and 323 eyes (86.8%) had pinhole visual acuity≥6/18 and 38 eyes (10.2%) had pinhole visual acuity<6/60. Main causes of visual impairment were uncorrected refractive error (63.9%) and comorbid eye disease (24.5%). Comorbid eye diseases associated with pinhole visual acuity<6/60 (n=23, 6.2%) included glaucoma, other optic nerve atrophy, vitreous haemorrhage and retinal detachment. Conclusions: The findings suggest that hands-on training remains safe and effective even when not implemented in centralized training centres. Further refinement of the training protocol, providing postoperative refractive services and more accurate preoperative intraocular lens calculations, can help optimize outcomes. © 2012 The Authors Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.

Five-year incidence and postoperative visual outcome of cataract surgery in urban southern China:The liwan eye study

Purpose. To determine the 5-year incidence and visual outcome of cataract surgery in an adult urban Chinese population. Methods. A comprehensive eye examination was performed at baseline and 5 years later on subjects participating in a population-based study. Incident cataract surgery was defined as having undergone surgery in either eye during the 5-year period. Postoperative visual impairment (PVI) was defined as visual acuity (VA) <6/18 based on both presenting VA (PVA) and best corrected VA (BCVA) in the operated eye. Results. Among the 1405 baseline participants, 75% (924) of survivors were seen at the 5-year follow-up visit. Forty-four returning participants (62 eyes) had undergone incident cataract surgery, an incidence of 4.84% (95% confidence interval [CI] - [3.53, 6.44]). Detailed medical and surgical records were available for 54/62 (87.1%) eyes, and of these, 5/ 54 (24.1%) had an immediate preoperative visual acuity <6/ 120. All recorded surgeries were performed at tertiary-level hospitals with phacoemulsification and foldable intraocular lens implantation. Those undergoing cataract surgery were more educated (P < 0.05) and had poorer baseline PVA in the worse-seeing eye (P < 0.001) than 54 persons with baseline PVA <6/18 due to cataract who had not had surgery. Among the 62 operated eyes, 22.6% (14/62) had PVI based on PVA and 9.6% (6/62) based on BCVA. Conclusions. Despite somewhat lower incidence, outcomes of cataract surgery in urban southern China are comparable with developed countries and better than for rural China. In urban China, emphasis should be on improving access to surgery. (Invest Ophthalmol Vis Sci. 2012;53:7936-7942) © 2012 The Association for Research in Vision and Ophthalmology, Inc.

A study of initial therapy for glaucoma in southern India: India Glaucoma Outcomes and Treatment (INGOT) Study.

PURPOSE: To compare initial glaucoma therapy with medications and trabeculectomy in southern India. METHODS: Patients aged ≥ 30 years newly diagnosed with glaucoma were randomized to trabeculectomy with 5-fluorouracil or medical therapy. Subjects with best-corrected vision <6/18 due to cataract underwent phacoemulsification (phaco/intraocular lens, IOL). Intraocular pressure (IOP), vision and visual function were assessed at 12 months. RESULTS: Patients assigned to medications and surgery received the expected therapy in 86% (172/199) and 64% (126/199) of cases, respectively. Forty patients (20%) assigned to surgery refused any treatment and 33 (17%) received medications. Among 199 patients randomized to medications, 52 (26.1%) underwent phaco/IOL, as did 89/199 (43.7%) of patients randomized to trabeculectomy. Baseline parameters of the two groups did not differ, nor did 1-year follow-up rates (medication 65%, trabeculectomy 58%, P = 0.15). Final IOP was lower with randomization to trabeculectomy (16.3 ± 5.1 mmHg) than medication (18.8 ± 6.7 mmHg, P < 0.0001). In regression models, randomization to trabeculectomy (P < 0.0001) was associated with lower IOP, and simultaneous trabeculectomy and cataract surgery was associated with higher IOP (P = 0.008) than trabeculectomy alone. Subjects receiving Phaco/IOL had significantly better final acuity (P < 0.0001) and visual function (P = 0.035), despite concurrent glaucoma treatment. Final visual acuity was worse in those receiving trabeculectomy in addition to cataract surgery, but this was of borderline significance (P = 0.06). CONCLUSIONS: Trabeculectomy lowered IOP significantly more than medical treatment, but with slightly greater loss of visual acuity. Combined phaco/IOL and trabeculectomy improved visual acuity with substantial IOP lowering.

Long-term graft survival in patients with flexible open-loop anterior chamber intraocular lenses

Purpose. To evaluate the long-term graft survival in patients with flexible open-loop anterior chamber intraocular lenses (AC IOL). Methods. We retrospectively reviewed the records of patients with aphakic/pseudophakic bullous keratopathy who underwent penetrating keratoplasty and flexible open-loop AC IOL implantation in our institution from 1983 to 1988. Results. 79 eyes from 77 patients were included in the study. Mean follow-up was 50 months (range 1 to 123 months). At last follow-up 61 eyes (77.2%) had clear grafts. Among them, the visual acuity was = 20/40 in 14 eyes (23.0%), 20/50-20/100 in 22 eyes (36.1%), 20/200-20/400 in 9 eyes (14.8%) and = CF in 16 (26.2%). Increment of glaucoma medications and/or glaucoma surgery was the most frequent complication (37 eyes, 46,8%). Cystoid macular edema was newly diagnosed in 10 eyes (12.7%). Conclusions. Flexible, open-loop anterior chamber lens are a viable option in the treatment of patients with aphakic or pseudophakic bullous keratopathy undergoing penetrating keratoplasty.

Determinants of postoperative corneal edema and impact on goldmann intraocular pressure.

PURPOSE: Recent studies report that increased corneal edema because of contact lens wear under closed lids is associated with elevated Goldmann intraocular pressure (GAT IOP). We sought to assess whether the impact of postoperative corneal edema on GAT IOP would be similar and to determine the differential effect of different amounts of edema. METHODS: The setting is a tertiary level cataract clinic in Shantou, China. Pre- and postoperative (day 1) GAT IOP, central corneal thickness (CCT), corneal hysteresis, corneal resistance factor, and radius of corneal curvature were measured for consecutive patients undergoing phacoemulsification surgery by 2 experienced surgeons. Corneal edema was calculated as the percentage increase in CCT. RESULTS: Among 136 subjects (mean age, 62.5 ± 15.4 years; 53.7% women), the mean increase in CCT was 10.3% postoperatively. Greater corneal edema was associated with lower GAT IOP in unadjusted analyses (P < 0.03) and in linear regression models (P < 0.01). In the model, higher corneal resistance factor (P < 0.001), lower corneal hysteresis (P < 0.001), and steeper radius of corneal curvature (P < 0.001) were associated with higher GAT IOP. Among subjects with edema < the median, edema was associated with lower GAT IOP (P = 0.004), whereas among those with edema ≥ the median, edema was not associated with GAT IOP. An increase in CCT of 7% was associated with an 8 mm Hg underestimation of GAT IOP in our models. CONCLUSIONS: The effect of postoperative edema on GAT IOP seems to be the opposite of contact lens-induced edema. The magnitude of the effect is potentially relevant to patient management.

Effectiveness of early lens extraction for the treatment of primary angle-closure glaucoma (EAGLE): a randomised controlled trial

Background
Primary angle-closure glaucoma is a leading cause of irreversible blindness worldwide. In early-stage disease, intraocular pressure is raised without visual loss. Because the crystalline lens has a major mechanistic role, lens extraction might be a useful initial treatment.

Methods
From Jan 8, 2009, to Dec 28, 2011, we enrolled patients from 30 hospital eye services in five countries. Randomisation was done by a web-based application. Patients were assigned to undergo clear-lens extraction or receive standard care with laser peripheral iridotomy and topical medical treatment. Eligible patients were aged 50 years or older, did not have cataracts, and had newly diagnosed primary angle closure with intraocular pressure 30 mm Hg or greater or primary angle-closure glaucoma. The co-primary endpoints were patient-reported health status, intraocular pressure, and incremental cost-effectiveness ratio per quality-adjusted life-year gained 36 months after treatment. Analysis was by intention to treat. This study is registered, number ISRCTN44464607.

Findings
Of 419 participants enrolled, 155 had primary angle closure and 263 primary angle-closure glaucoma. 208 were assigned to clear-lens extraction and 211 to standard care, of whom 351 (84%) had complete data on health status and 366 (87%) on intraocular pressure. The mean health status score (0·87 [SD 0·12]), assessed with the European Quality of Life-5 Dimensions questionnaire, was 0·052 higher (95% CI 0·015–0·088, p=0·005) and mean intraocular pressure (16·6 [SD 3·5] mm Hg) 1·18 mm Hg lower (95% CI –1·99 to –0·38, p=0·004) after clear-lens extraction than after standard care. The incremental cost-effectiveness ratio was £14 284 for initial lens extraction versus standard care. Irreversible loss of vision occurred in one participant who underwent clear-lens extraction and three who received standard care. No patients had serious adverse events.

Interpretation
Clear-lens extraction showed greater efficacy and was more cost-effective than laser peripheral iridotomy, and should be considered as an option for first-line treatment.