Extracapsular Cataract Surgery Research Articles

The effect of vitreous presentation during extracapsular cataract surgery on the postoperative visual acuity at one year

The purpose of this study was to determine the effects that vitreous presentation (VP) during extracapsular cataract surgery has on patients' 1-year postoperative vision. The study was a prospective, long-term, clinical trial. The study took place at 19 Department of Veterans Affairs medical centers. Patients having VP during cataract surgery and receiving a posterior chamber (PC) intraocular lens (IOL) (230 patients) were prospectively compared with a 5% random sample of nonvitreous presentation (NVP) cataract surgery patients (521 patients). Best-corrected visual acuity (BCVA) at 1 year was obtained by a masked, certified examiner. There was no statistical difference (P = .089) between the VP patients receiving PC IOL and the NVP patients in percentage of patients having BCVA of 20/40 or better at 1 year (91.1% vs 94.9%). There were significantly more PC IOL VP patients than NVP patients with BCVA of 20/50 or worse at some time during the first postoperative year (21.6% vs 10.9%; P = .0003), significantly fewer with BCVA of 20/20 or better at 1 year (27.8% vs 38.8%; P = .013), and significantly more with cystoid macular edema (11.5% vs 3.6%; P = .0002), retinal detachment (4.3% vs 0.2%; P = .0002), and uveitis (3.4% vs 0.6%; P = .012). The NVP patients rated their vision as very good or excellent significantly more often than the VP patients (71% vs 58%; P = .025). Vitreous presentation during extracapsular cataract surgery leads to somewhat worse overall outcomes in patients, although the majority of patients with VP do reasonably well.

Triple surgery. Keratoplasty combined with cataract extraction and intraocular lens implantation

Since the 1980s, combined perforating keratoplasty and extracapsular cataract surgery with intraocular lens implantation (triple procedure) has been performed with increasing success for patients with corneal disease and cataract. Advantages include prompt visual rehabilitation, protection of the transplanted endothelium from sequential cataract surgery, and similar up to superior functional results following triple procedures. In the following review article, the authors discuss advantages and disadvantages of triple procedures, alternative surgical techniques, problems in intraocular lens power calculation, intraoperative pitfalls, and postoperative results of combined keratoplasty, cataract removal, and intraocular lens implantation.

Cost-effectiveness analysis of cataract surgery: a global and regional analysis.

To estimate the population health effects, costs and cost effectiveness of selected cataract surgery interventions in areas of the world with different epidemiological profiles. Effectiveness estimates are based on a review of the literature taking into account factors such as operative failure, complications and patient non-compliance. A population model was applied to follow the lifelong impact on individuals having cataract surgery. Costing estimates are based on primary data collected in 14 epidemiological subregions by regional costing teams and on a literature review. Costings were estimated for different geographical coverage levels using non-linear cost functions. Intra- and extra-capsular cataract surgeries are cost-effective ways to reduce the impact of cataract-blindness. Extra-capsular cataract surgery is more cost-effective than intra-capsular surgery in all regions considered. Providing extra-capsular cataract surgery to 95% of those who need it (95% coverage level) would avert over 3.5 million disability-adjusted life years (DALYs) per year globally. The cost-effectiveness ranges from 57 International dollars (1 dollar) per DALY in the WHO South-East Asia Region where there is high overall child and adult mortality to 1 dollar 2307 per DALY in the WHO Western Pacific Region where there is low overall child and adult mortality. Extra-capsular surgery for cataracts at a high level of coverage is the most cost-effective way of restoring sight in all epidemiological subregions considered. Analysts from countries within a region are encouraged to further contextualize the results based on their own country's specific parameters.

Effect of cataract surgery on the corneal endothelium: Modern phacoemulsification compared with extracapsular cataract surgery

Purpose To investigate whether modern phacoemulsification surgery results in more damage to the corneal endothelium than extracapsular cataract extraction (ECCE), and to examine which preoperative, operative, and postoperative factors influence the effect of cataract surgery on the endothelium. Design Randomized controlled trial. Participants Five hundred patients 40 years or older were randomized into 2 groups (ECCE, 249; phacoemulsification, 251). Methods Central corneal endothelial cell counts, coefficient of variation of cell size, and hexagonality were assessed before surgery and up to 1 year postoperatively. Main outcome measure Endothelial cell count. Results Four hundred thirty-three patients completed the trial. The initial preoperative mean cell count for the entire sample was 2481 (standard error [SE]: 18.6), reduced at 1 year postoperatively to 2239 (SE: 23.5). An average 10% reduction in cell count was recorded by 1 year postoperatively. There was no such change in hexagonality or in the coefficient of variation. There was no significant difference in overall percentage cell loss between the 2 treatment groups. Factors associated with excessive cell loss (≥15% by 1 year) were a hard cataract (odds ratio [OR]: 2.1, 95% confidence limits: 1.1–4.1; P = 0.036), age (OR: 1.04, P = 0.005), and capsule or vitreous loss at surgery (OR: 2.38, P = 0.106). Phacoemulsification carried a significantly higher risk (OR: 3.7, P = 0.045) of severe cell loss in the 45 patients with hard cataracts relative to ECCE (52.6% vs. 23.1%; chi-square test, P = 0.041), with both procedures achieving similar postoperative visual acuity outcomes. Conclusions No significant difference in overall corneal endothelial cell loss was found between these 2 operative techniques. The increased risk of severe cell loss with phacoemulsification in patients with hard cataracts suggests that phacoemulsification may not be the optimal procedure in these cases, and that ECCE should be preferred.

Analysis of lens protein after extracapsular cataract surgery

Analysis of lens protein after extracapsular cataract surgery

Sudden decrease in vision caused by liquefied after-cataract

We report a case of sudden decrease to unilateral visual acuity in a 39-year-old patient who had extracapsular cataract surgery 5 years earlier. The decrease was caused by involvement of the visual axis because of a rare complication known as liquefied after-cataract. Treatment with a neodymium:YAG (Nd:YAG) laser was successfully performed. Although there was no rupture in the posterior capsule, the opacity disappeared and the visual acuity improved to 20/20. This new form of after-cataract can cause a sudden decrease in vision, and Nd:YAG laser treatment, even without a posterior capsule rupture, can be performed successfully.

Essential ophthalmic surgery

Alexander J. E. Foss Essential ophthalmic surgery320 pagesButterworth Heinemann, Oxford, 2001ISBN 0 7506 4197 5Price: £35 The aim of this book is to provide the trainee ophthalmic surgeon with a basic understanding of ocular surgery. The text is divided into three main sections, covering the basic principles of surgery, ocular anaesthesia and surgical techniques. The first section looks at general considerations regarding instrumentation, wound creation, wound closure, wound healing and aftercare, controlled tissue destruction and the use of different fluids in ocular surgery. These topics are often not dealt with systematically during ophthalmological training, and thus the present short review is useful. Examples of the basic issues presented include recommendations regarding the use of tissue adhesives in ophthalmic surgery, and illustrations of how a slip knot is deliberately made and how accidental slip knots can be avoided. The second section consists of a short and concise overview of the different types of anaesthesia used in ocular surgery, with emphasis on the use of regional blocks. The third section describes the most commonly performed operations. As the book is primarily meant for the trainee ophthalmic surgeon, it covers the surgery with which a candidate for the Royal College of Ophthalmologists' fellowship examination is expected to be familiar. It offers practical advice for each procedure, describing how to judge the depth when placing corneal sutures, how to avoid an unintended circumferential torque when making a continuous graft suture, what to do when experiencing difficulties in expressing the lens nucleus during extracapsular cataract surgery and how to handle posterior capsular rupture during phacoemulsification. In addition to chapters describing the techniques and pitfalls associated with the procedures most commonly performed by the general ophthalmic surgeon, the book contains sections on ocular biometry and orbital and lens implant biomaterials and design. The author describes the book's primary purpose as being to cover 'all that we would like to know, but are afraid to ask'. He goes on to state that surgery is about learning tricks, and says that he has tried to include as many of these tricks as possible. In my opinion, he has fulfilled both these objectives satisfactorily. The layout of the book may at first glance be considered somewhat old-fashioned, with its simple, schematic drawings exclusively in black and white, but the drawings are illustrative, and, in general, no information is lost due to the lack of colour. Its short, concise and well-written text makes the book easily accessible and it is reasonably priced. The author begins his preface with a quotation from a fellow ophthalmologist: 'Surgery is about learning monkey tricks, but finding a good monkey can be difficult'. Appropriately, the demand for 'good monkeys' may be considerably fulfilled by use of the present textbook.

Flurbiprofen-loaded acrylate polymer nanosuspensions for ophthalmic application

Polymeric nanoparticle suspensions were prepared from Eudragit RS100 ® and RL100 ® polymer resins and loaded with flurbiprofen (FLU), with the aim at improving the availability of the drug at an intra-ocular level for the prevention of the myosis induced during extracapsular cataract surgery. Nanosuspensions were prepared by a quasi-emulsion solvent diffusion technique using different formulation parameters (drug-to-polymer ratio, initial polymer concentration, agitation speed, etc.). The resulting nanoparticles showed mean sizes around 100 nm and a fixed positive charge ( ξ-potential around +40/+60 mV). Stability tests after mid-time storage (4°C or room temperature) or freeze-drying were carried out to optimise a possible final pharmaceutical preparation. In vitro, dissolution tests showed a controlled release profile of FLU from the nanoparticles. In vivo anti-inflammatory efficacy was assessed in the rabbit eye after induction of an ocular trauma (paracentesis). FLU-loaded nanosuspensions did not show toxicity on ocular tissues. Moreover, an inhibition of the miotic response to the surgical trauma comparable to a control eye-drop formulation was obtained, even though an actual lower concentration of free drug in the conjunctival sac was achieved from the nanoparticle system. Drug levels in the aqueous humour were also higher after application of the nanosuspensions.

Survey of intraocular lens material and design.

Modern cataract surgery is constantly evolving and improving in terms of lens material and design. Researchers and physicians strive to obtain better refractive correction with smaller wound size and minimizing host cell response to limit the proliferation of lens epithelial cells leading to opacification of the lens capsule. Intraocular lens material varies in water content, refractive index, and tensile strength. Intraocular lens design has undergone revisions to prohibit lens epithelial cell migration and reflection of internal and external light. The evolution of intraocular lens and extracapsular cataract surgery has lead to faster postoperative recovery and better visual outcomes.

Cataract surgery in patients with Behçet’s disease

Purpose: To evaluate the outcomes and complications of cataract surgery in patients with Behçet’s disease. Setting: Department of Ophthalmology, Hacettepe University School of Medicine, Ankara, Turkey. Methods: Thirty-three eyes of 26 patients with Behçet’s disease that had extracapsular cataract surgery between January 1993 and July 1999 were analyzed retrospectively. The mean age of the patients was 38.9 years (range 20 to 54 years). The mean postoperative follow-up was 22.9 months (range 6 to 66 months). Results: Extracapsular cataract extraction (ECCE) was performed in 22 eyes with and in 6 eyes without intraocular lens (IOL) implantation. Phacoemulsification with IOL implantation was performed in 5 eyes. Postoperatively, the visual acuity was better in 29 eyes (87.8%) and was 0.5 or better in 14 eyes (42.4%). Posterior segment complications of Behçet’s disease, mainly optic atrophy and macular alterations from preoperative inflammatory episodes, restricted final acuity. No significant difference was detected in postoperative inflammation among the types of surgery; that is, ECCE, ECCE with IOL implantation, and phacoemulsification with IOL implantation. A neodymium:YAG laser posterior capsulotomy was performed in 3 cases. Conclusions: In patients with Behçet’s disease, inflammation after extracapsular surgery was mild when surgery was performed after at least 3 months of no inflammatory signs. The results show that the outcomes of extracapsular cataract surgery mainly depend on the degree of preoperative posterior segment involvement.

O uso de lentes intra-oculares em pacientes portadores de Hanseníase

Purpose: To evaluate the ocular alterations due to cataract surgery with IOL implant in leprosy patients and compare them with patients without leprosy. Methods: In this study, 122 leprosy patient eyes and 71 eyes from patients without leprosy underwent extracapsular cataract surgery and/or phacoemulsification with IOL implant and were examined periodically after the operation. Results: Ocular alterations due to surgery and IOL presence were found more often in leprosy patients. Conclusions: IOL used in leprosy patient is an appropriate procedure when we face patients with the disease handicaps.

"Masked" pseudoexfoliation syndrome in unoperated eyes with circular posterior synechiae: clinical-electron microscopic correlation.

To investigate the prevalence of "masked" pseudoexfoliation (PEX) syndrome in eyes with circular posterior synechiae receiving antiglaucomatous therapy with miotics. Cross-sectional prospective study. Twenty-eight eyes of 27 consecutive patients with circular posterior synechiae and a history of miotic drug use without previous intraocular surgery, inflammation, or trauma, and without conventional signs of PEX material in the anterior chamber were included in the study. All eyes were investigated by slitlamp biomicroscopy and gonioscopy of the anterior chamber before extracapsular cataract surgery for the presence of typical PEX-associated iris pigment epithelial changes, such as peripupillary atrophy and trabecular meshwork melanin granule deposition. The anterior chamber depth, lens thickness, and axial lengths of the eyes were measured by A-scan immersion sonography. The excised anterior lens capsules obtained during extracapsular cataract surgery were investigated for the presence of precapsular fibrillar PEX deposits by electron microscopy. The prevalence of masked PEX syndrome in eyes with circular posterior synechiae receiving antiglaucomatous therapy with miotics. Transmission electron microscopy of unselected nonserial sections revealed a precapsular layer consisting of typical PEX fibers or microfibrils, which indicated early stages of PEX syndrome in 18 (64%) of 28 eyes with circular posterior synechiae. Melanin granules were frequently found adhering to the fibrillar layer. Eyes with precapsular fibrillar deposits showed significantly greater trabecular meshwork pigmentation than eyes without such deposits. Differences in age, lens thickness, axial length of the eye, anterior chamber depth, and degree of peripupillary atrophy were, however, not statistically significant between the groups with and without electron microscopic evidence of PEX deposits. Circular posterior synechiae were more frequently associated with manifest or early stages of PEX syndrome. However, the formation of broad posterior synechiae in miosis prevented a definite clinical diagnosis based on the classic changes of the anterior lens capsule. In eyes with spontaneous or miotic-induced circular posterior synechiae without other obvious cause, the masked variant of PEX syndrome should always be considered.

Posterior capsule opacification and anterior capsule opacification.

Posterior capsule opacification (PCO) is still the most frequent complication of cataract surgery. A variety of studies has led to a better understanding of the pathogenesis of PCO, and strategies of molecular biology have produced new therapeutic options, such as immunological techniques or gene therapeutic approaches. Surgical strategies and intra-ocular lens-dependent factors also are capable to reduce the rate of PCO. In-the-bag implantation of intra-ocular lenses with a sharp optic edge seems to be effective in inhibiting equatorial lens epithelial cell migration to the center of the posterior capsule. Several PCO documentation systems have been developed that will lead to more exact and better comparable recording of PCO rates. In the year 2000, PCO or secondary cataract is still the most frequent complication after extracapsular cataract surgery. In a 1998 meta-analysis, PCO rates of 11.8% 1 year after extracapsular cataract surgery with intraocular lens implantation, 20.7% after 3 years, and 28.4 % after 5 years have been reported. For the United States, it has been estimated that the overall expenses for treatment of PCO are only exceeded by the costs for cataract treatment itself. In the past decade, a lot of experimental and clinical studies have been performed on this topic. They have led to 1) to a better understanding of the pathogenesis of the development of anterior and posterior capsule opacification; 2) more objective and better comparable systems of documentation and analysis of PCO; and a number of 3) surgical and 4) pharmaceutical strategies to prevent PCO.

Outcome of extracapsular cataract surgery plus posterior chamber intraocular lens insertion for age-related cataract in eastern Nepal.

As age-related cataract is the leading cause of blindness in Nepal, much more attention should be given to improving surgical outcomes. The aim of our study was to determine the effectiveness and risks of extracapsular cataract surgery (ECCE) for age-related cataract in a tertiary hospital of eastern Nepal. ECCE with posterior chamber intraocular lens (PC IOL) insertion on 797 eyes (754 patients) revealed improved visual acuity in 97.9%. In 595 (74.6%) the best corrected visual acuity was 6/18 or better, and 167 (20.9%) had 6/24 to 6/60 with negligible operative/postoperative complications. Thus it is concluded that ECCE with PC IOL could be performed safely and effectively even in developing countries where people are unaware that surgery is available and of the good surgical outcome.

Small incision extracapsular cataract surgery with manual phacotrisection

Purpose To evaluate the safety and efficacy of small incision extracapsular cataract extraction (ECCE) using the manual phacotrisection technique. Setting Department of Ophthalmology, Turgut Özal Medical Center, Inönü University, Malatya, Turkey. Methods Fifty-nine eyes of 54 patients had small incision ECCE by the manual phacotrisection technique. Mean follow-up was 10 months. After capsulorhexis and hydrodissection were performed, the endonucleus was prolapsed into the anterior chamber and trisected using an anteriorly positioned triangular trisector and posteriorly placed solid vectis. Pieces were extracted with a forceps through a small incision. Results Postoperatively, best spectacle-corrected visual acuity of 20/40 or better was achieved in 48 eyes (83%) and of 20/25 or better in 28 eyes (47%). The most frequent intraoperative complication was posterior capsule rupture (n = 5). Of eyes that developed posterior capsule rupture, 3 had vitreous loss and 2 had implantation of an anterior chamber intraocular lens (IOL). In 44 eyes, the IOL was implanted in the bag and in 12 eyes, in the ciliary sulcus. The most significant postoperative complication was transient corneal edema, which developed in 32 eyes (54%). No permanent complications (e.g., corneal endothelial decompensation) occurred in any case. Conclusion Manual phacotrisection has several advantages such as nucleus safety, less dependence on assistant personnel, the elimination of the phaco machine, and cost effectiveness.

Hardness and ultrasonic characteristics of the human crystalline lens

Purpose To evaluate the relationship between hardness of the human crystalline lens and its acoustic characteristics. Setting St. George’s Hospital Medical School, University of London, London, United Kingdom. Methods Cataractous lenses from patients who had extracapsular cataract surgery were studied for hardness and ultrasonic characteristics. Lens hardness was assessed with an automated guillotine. Ultrasound velocity and attenuation were measured with a scanning acoustic macroscope using the pulse transmission reflection method. Results Thirty-seven lenses from 37 patients (mean age 75.5 years) were evaluated. Lens hardness was associated with ultrasound attenuation ( r = 0.65, P < .0001) and attenuation frequency gradient ( r = 0.67, P < .0001). The correlation of hardness with mean ultrasound velocity was not significant ( r = 0.22, P = .2). Conclusions The attenuation of ultrasound waves by the human crystalline lens correlated with its hardness. Ultrasonography can be used to evaluate lens hardness.

Complications of extracapsular cataract surgery in chronic renal failure patients.

In chronic renal failure (CRF) patients the risk of per- and post-operative complications in cataract surgery is high. The most frequent complications observed in these patients and the prevalence of cataract were studied. Eighty-two CRF patients who had undergone ophthalmic examination between December 1996 and April 1998 at Başkent University, Department of Ophthalmology, were retrospectively analysed. Of 82 patients, 18 eyes of 14 CRF patients between 37 and 79 years of age underwent cataract extraction. Planned extracapsular cataract extraction was performed in all patients and all but one had posterior chamber intraocular lens implantation. In the post-operative period, scrapings of the corneal infiltrates were cultured and smears were examined, and the conjunctiva was swabbed and cultured also. Per-operative hypotony and scleral collapse occurred in 1 patient, and another had haemorrhage in the anterior chamber. Post-operatively, suture infiltration was observed in 10 eyes. These lesions disappeared after topical steroid and antibiotic treatment. Patients with CRF require special surgical considerations since they face both general surgical problems and others that arise due to their disease.

Phacoemulsification versus extracapsular cataract extraction in patients with diabetes

ObjectiveTo compare phacoemulsification with extracapsular cataract surgery in patients with diabetes and to identify determinants of postoperative visual acuity. DesignProspective, randomized, paired-eye trial. ParticipantsForty-six patients with diabetes and bilateral cataract. InterventionPatients were allocated to phacoemulsification surgery with silicone intraocular lens to one randomly determined eye, and extracapsular cataract surgery with 7-mm polymethylmethacrylate intraocular lens to the other. Main outcome measuresLogarithm of minimum angle of resolution visual acuity (logMAR VA), incidence of clinically significant macular edema (CSME), retinopathy progression, indices of anterior segment inflammation, and incidence of capsulotomy. ResultsCompared with eyes undergoing phacoemulsification, eyes managed with extracapsular surgery had more anterior chamber cells (P = 0.0004) and flare (P = 0.007) 1 week after surgery and a higher incidence of posterior synechiae (P = 0.04) and intraocular lens deposits (P < 0.0005) in the first postoperative year. The need for posterior capsulotomy was greater in eyes undergoing extracapsular surgery (16 of 46 vs. 5 of 46, P = 0.01). No difference in incidence of postoperative CSME, progression of retinopathy, or development of high-risk proliferative retinopathy was identified between techniques (P = 1.0, 0.8, and 0.2). Median 1-year logMAR VA was worse in eyes undergoing extracapsular surgery (0.08 vs. 0.06, P = 0.02), especially in those with retinopathy (0.14 vs. 0.08, respectively; P = 0.01). The presence or absence of CSME at the time of surgery was the most significant determinant of 1-year logMAR VA in regression models for both extracapsular (P = 0.0004, R2 = 0.45) and phacoemulsification groups (P < 0.00005, R2 = 0.46). ConclusionsPhacoemulsification is associated with better postoperative VA, less postoperative inflammation, and less need for capsulotomy than extracapsular cataract surgery in patients with diabetes. However, with both techniques, the principal determinant of postoperative VA appears to be the presence or absence of CSME at the time of surgery. Early intervention, reducing the risk that unrecognized CSME is present at the time of surgery, may be more critical to outcome than choice of surgical technique.

Effectiveness of sub-Tenon’s versus peribulbar anesthesia in extracapsular cataract surgery

Purpose To compare the effectiveness of sub-Tenon’s versus peribulbar anesthesia in extracapsular cataract surgery. Setting Department of Ophthalmology and the Maccabi Eye Institute, Tel Aviv, Israel. Methods Sixty-four consecutive patients who had extracapsular cataract surgery were randomized to have sub-Tenon’s or peribulbar anesthesia. Intraocular pressure (IOP) was measured before and 1 and 10 minutes after injection. The motility of the rectus muscles was evaluated before and 20 minutes after the injection, and the patient’s anxiety level was recorded immediately after the injection. Pain was assessed intraoperatively and 1 and 24 hours postoperatively by patient self-grading. Results One minute after the injection, IOP increased significantly in the peribulbar group (mean 7.97 mm Hg ± 8.80 [SD]) ( P < .05). There was no significant increase in the sub-Tenon’s injection group (mean 0.12 ± 3.09 mm Hg). In both groups, IOP returned to preinjection levels by 10 minutes postoperatively. Patients with peribulbar anesthesia reported a significantly higher level of anxiety than those who had sub-Tenon’s anesthesia ( P < .05). Although the intraoperative pain levels were the same, the sub-Tenon’s group reported significantly higher levels of pain 1 and 24 hours postoperatively; 16% in the sub-Tenon’s group and none in the peribulbar group reported moderate pain 24 hours after anesthesia. Ocular motility was the same except for the inferior rectus muscle, which was less motile on average in the peribulbar group. Conclusion Sub-Tenon’s anesthesia led to less IOP elevation than peribulbar anesthesia and provided similarly good globe immobilization and approximately the same pain levels intraoperatively.

Results of small incision extracapsular cataract surgery using the anterior chamber maintainer without viscoelastic

AIMSTo assess the efficacy of extracapsular cataract surgery using the anterior chamber maintainer (ACM) without the use of viscoelastic. To compare the effects of this surgical technique on non-diabetic and...