Extracapsular Surgery Research Articles

Comparison between remifentanil, propofol or both for sedation during retrobulbar nerve block

Objectives: To compare between the efficacy of remifentanil and propofol and combination of both for analgesia during retrobulbar nerve block in cataract surgery. Materials and Methods: A prospective randomised double blind study conducted in King Hussein Medical Center in Royal Medical Services during the period between September 2004 and August 2005. 160 patients undergoing extra capsular cataract extraction surgery under retrobulbar anaesthesia were enrolled in the study. Patients were randomly divided into four groups (40 patients in each group) and received different drug combinations by the same anaesthetist as follows: remifentanil 0.3 microgram/kg (group 1), propofol 0.5 mg/kg (group 2), remifentanil 0.3 microgram/kg and propofol 0.5 mg/kg (group 3) and saline 0.1 ml/kg as a placebo (group 4). Patient’s movement and pain were observed during the injection. Heart rate, respiratory rate and haemoglobin oxygen saturation were observed every minute for 10 minutes after the block. Results: No significant movement occurred in group 3 during the placement of the block compared to half of the patients in the control group. The mean visual analogue score was 2.3 in group 3 compared to 6.7 in group 4. There was no significant change in mean heart and respiratory rates and haemoglobin oxygen saturation among the three study groups. Conclusion: Patients undergoing cataract surgery under retrobulbar anaesthesia, a combination of remifentanil 0.3 microgram/kg and propofol 0.5 mg/kg is considered to provide excellent relief of pain with least patient movement and minimal respiratory and cardiac side effects.

Effect of intraocular lens edge profile on posterior capsule opacification after extracapsular cataract surgery in a developing country

To determine whether square-edged polymethyl methacrylate (PMMA) intraocular lenses (IOLs) reduce posterior capsule opacification (PCO) in the context of extracapsular cataract surgery in a developing country. A rural hospital in India. This was a prospective randomized double-masked fellow-eye controlled study. Over a 4-month period, 118 patients with normal eyes apart from age-related cataract were randomized to receive a square-edged or round-edged PMMA IOL in the first eye. The IOLs were identical apart from the edge profile. The fellow-eye had implantation of the alternative IOL within 1 month. Retroillumination images of the posterior capsule were taken using a dedicated camera system and analyzed to quantify the PCO area using POCO software 1 and 2 years postoperatively and the PCO area and severity using POCOman semiqualitative software at 2 years. Visual acuity was measured using a Gujarati logMAR chart. One hundred fifteen patients were available for examination at 1 year and 107 at 2 years. With POCO software, the PCO area was reduced in the square-edged IOL group at 1 year (median 30% versus 20%, P=.001) and at 2 years (median 45% versus 35%, P=.006). With POCOman, the PCO area and severity were reduced in the square-edged group at 2 years (median 41.5% versus 33.2%, P=.019 and 0.59 versus 0.46, P=.037, respectively). There was no significant difference in visual acuity between the 2 groups at 1 or 2 years. Sophisticated image analysis techniques can be used in developing countries to quantify PCO. Using extracapsular surgery, square-edged PMMA IOLs reduced the PCO area and severity compared with an identical round-edged IOL; however, the differences were not as marked as those reported with phacoemulsification. This may be due to the difficulty of performing a capsulorhexis that lies on the IOL surface in this situation. Nevertheless, square-edged IOLs offer a potential benefit for extracapsular surgery in the developing world.

Surgical interventions for age-related cataract

BACKGROUND: Cataract accounts for 50% of blindness globally and remains the leading cause of visual impairment in all regions of the world, despite improvements in surgical outcomes (WHO 2005). This number is expected to rise due to an aging population and increase in life expectancy. Although cataracts are not preventable, their surgical treatment is one of the most cost-effective interventions in healthcare. OBJECTIVES: To compare the effects of different surgical interventions for age-related cataract. SEARCH STRATEGY: We searched CENTRAL, MEDLINE, EMBASE up to July 2006, NRR Issue 3 2005, the reference lists of identified trials and we contacted investigators and experts in the field for details of published and unpublished trials. SELECTION CRITERIA: We included randomised controlled trials (RCTS). DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and discrepancies were resolved by discussion. Where appropriate, risk ratios, odds ratios and weighted mean differences were summarised after assessing heterogeneity between the studies. MAIN RESULTS: We identified 17 trials that randomised a total of 9627 people. Phacoemulsification gave a better visual outcome than extracapsular surgery but similar average cost per procedure in Europe but not in poorer countries. Extracapsular surgery with posterior chamber lens implant and ICCE with or without an anterior chamber intraocular lens (IOL) implant gave acceptable visual outcomes but extracapsular surgery had less complications. Manual small incision surgery provides better visual outcome than ECCE but slightly inferior unaided visual acuity compared to phacoemulsification. AUTHORS' CONCLUSIONS: This review provides evidence from seven RCTs that phacoemulsification gives a better outcome than ECCE with sutures. We also found evidence that ECCE with a posterior chamber lens implant provides better visual outcome than ICCE with aphakic glasses. The long term effect of posterior capsular opacification (PCO) needs to be assessed in larger populations. The data also suggests that ICCE with an anterior chamber lens implant is an effective alternative to ICCE with aphakic glasses, with similar safety. Phacoemulsification provides the best visual outcomes but will only be accessible to the poorer countries if the cost of phacoemulsification and foldable IOLs decrease. Manual small incision cataract surgery provides early visual rehabilitation and comparable visual outcome to PHACO. It has better visual outcomes than ECCE and can be used in any clinic that is currently carrying out ECCE with IOL. Further research from developing regions are needed to compare the cost and longer term outcomes of these procedures e.g. PCO and corneal endothelial cell damage.

Heavier molecular weight ocular viscoelastic devices and timing of post-operative review following cataract surgery

BackgroundTo assess the safety of abandoning the next day post-operative review in preference for assessment only 2 hours post-surgery for both phacoemulsification and extracapsular surgery with heavier molecular weight ocular viscoelastic devices (OVD).Methods475 patients who underwent uncomplicated cataract surgery using heavier molecular weight ocular viscoelastic device (Healon GV) were studied. Of these 415 were phacoemulsification and 60 extracapsular and none received Intraocular pressure (IOP) lowering prophylaxis at the end of surgery. All were examined at 2 hours post-surgery and on the following day. Results were tabulated and analysed assessing wound stability, corneal clarity, anterior chamber reaction and IOP.ResultsIn the time between the two assessments 44 (10.6%) patients developed a total of 53 new problems, with a majority being increases in IOP. Based on the lower threshold of IOP of 30 mmHg, the incidence of new problems at the next-day assessment was 9.8% (95% CI: 7.0 to 13.6) in the phacoemulsification group and 16.3% (7.3 to 29.7)in the extracapsular surgery group. At the higher threshold of IOP of 35 mmHg the corresponding figures were 6.6% and 16.3%.ConclusionThere is a higher incidence of new problems at the next-day assessment than previous studies with conventional OVD. Therefore results from previous studies using standard OVDs cannot be simply extrapolated to heavier molecular weight OVDs. When these agents are used, routine use of an ocular hypotensive agent may be necessary to increase the safety of abandoning the review on the first post-operative day for phacoemulsification patients. This is to be studied.

Patellar luxation as a complication of surgical intervention for the management of cranial cruciate ligament rupture in dogs

This retrospective study identified 32 cases of patellar luxation which occurred as a complication of surgical intervention for cranial cruciate ligament rupture (CCLR). The complication was recorded mostly in larger (>/=20 kg) dogs with the Labrador Retriever being the most common breed. The complication followed extra-capsular, intra-capsular and tibial plateau levelling surgery. The mean time from CCLR surgery to the diagnosis of patellar luxation was 14 weeks. The incidence of patellar luxation occurring as a complication of surgical intervention for CCLR was 0.18% of all CCLR corrective procedures. Corrective surgery for patellar luxation was successful in 79% of stifles. The patellar reluxation rate was significantly lower (p = 0.0007) when at least one corrective osteotomy (tibial tuberosity transposition, femoral trochlear sulcoplasty or tibial plateau levelling osteotomy with tibial axial re-alignment) was performed (35%), compared to when corrective osteotomy was not performed (100% patellar reluxation rate). When performing corrective surgery for patellar luxation following CCLR surgery, at least one corrective osteotomy should be performed in order to reduce the patellar reluxation rate. The correction of patellar luxation following surgery for CCLR is challenging and carries a significant rate of failure.

Surgical interventions for age-related cataract

Cataract accounts for 50% of blindness globally and remains the leading cause of visual impairment in all regions of the world, despite improvements in surgical outcomes (WHO 2005). This number is expected to rise due to an aging population and increase in life expectancy. Although cataracts are not preventable, their surgical treatment is one of the most cost-effective interventions in healthcare. To compare the effects of different surgical interventions for age-related cataract. We searched CENTRAL, MEDLINE, EMBASE up to July 2006, NRR Issue 3 2005, the reference lists of identified trials and we contacted investigators and experts in the field for details of published and unpublished trials. We included randomised controlled trials (RCTS). Two review authors independently extracted data and discrepancies were resolved by discussion. Where appropriate, risk ratios, odds ratios and weighted mean differences were summarised after assessing heterogeneity between the studies. We identified 17 trials that randomised a total of 9627 people. Phacoemulsification gave a better visual outcome than extracapsular surgery but similar average cost per procedure in Europe but not in poorer countries. Extracapsular surgery with posterior chamber lens implant and ICCE with or without an anterior chamber intraocular lens (IOL) implant gave acceptable visual outcomes but extracapsular surgery had less complications. Manual small incision surgery provides better visual outcome than ECCE but slightly inferior unaided visual acuity compared to phacoemulsification. This review provides evidence from seven RCTs that phacoemulsification gives a better outcome than ECCE with sutures. We also found evidence that ECCE with a posterior chamber lens implant provides better visual outcome than ICCE with aphakic glasses. The long term effect of posterior capsular opacification (PCO) needs to be assessed in larger populations. The data also suggests that ICCE with an anterior chamber lens implant is an effective alternative to ICCE with aphakic glasses, with similar safety. Phacoemulsification provides the best visual outcomes but will only be accessible to the poorer countries if the cost of phacoemulsification and foldable IOLs decrease. Manual small incision cataract surgery provides early visual rehabilitation and comparable visual outcome to PHACO. It has better visual outcomes than ECCE and can be used in any clinic that is currently carrying out ECCE with IOL. Further research from developing regions are needed to compare the cost and longer term outcomes of these procedures e.g. PCO and corneal endothelial cell damage.

Risk Factors of Massive Suprachoroidal Hemorrhage during Extracapsular Cataract Extraction Surgery

To estimate retrospectively the incidence, predisposing factors, and possible mechanisms precipitating massive suprachoroidal hemorrhage (MSCH) development during cataract extraction surgery. The study was conducted on 6639 consecutive cataract extractions performed between 1994 and 2002. All of the procedures were carried out using traditional nucleus expression methods. The study cases comprised 19 patients who developed intraoperative MSCH. The remaining 6620 patients served as the control group. Baseline systemic and ocular characteristics, as well as intraoperative factors, were analyzed. Categorical variables were analyzed using the chi-square test and the Fisher exact test. The incidence of MSCH during cataract surgery was 0.28%. Highly significant risk factors included high myopia, glaucoma, and diabetes (p<0.01). Atherosclerotic vascular diseases and/or hypertension were less significantly related to the condition (p<0.05). There was no significant relationship between MSCH formation and age, sex, side of the cataract, history of ocular trauma, or inflammation. The incidence of MSCH did not differ between patients operated on with extracapsular or intracapsular cataract extraction. Attention to multiple preoperative and intraoperative ocular and systemic variables may allow the identification of, and prophylaxis for, patients at greater risk for MSCH.

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.

Épanchement sanguin endocapsulaire post-traumatique

A rare complication after extracapsular surgery of the cataract, blood effusion is often a fortuitous discovery when a drop in visual acuity occurs. The subject reported herein is a 76-Year-old patient who presented an endocapsular blood effusion with no liquid level 1 Year after the extracapsular surgery of the cataract, discovered while examining a decrease in visual acuity. Questioning led to the discovery of eye trauma due to Nd: YAG laser posterior capsulotomy 3 Months before, which had progressed spontaneously and favorably for 2 Months, with a reduction of the effusion and better visual acuity. The bleeding seems to have come from a vascular injury due to a direct contusion, with blood possibly coming from the ciliary body, the iridocorneal angle, or the vitreous. The liquid effusion may have been caught at the back by the implant and enclosed in the area located between the capsular bag and the anterior hyaloid, without intravitreous diffusion. Most of reported cases in the literature discuss observations made on an intact posterior capsule, which appeared during or after close surgery. The treatment was simple supervision. Some Authors propose a Nd: YAG laser capsulotomy in case resorption is too slow.

Small-incision manual extracapsular cataract surgery in Ghana, West Africa

Purpose To evaluate the results of small-incision manual extracapsular cataract extraction surgery (ECCE) in a district hospital in West Africa. Setting Margret Marquart Catholic Hospital, Ghana, West Africa. Methods This prospective study consisted of 200 eyes of 193 patients who had small-incision manual ECCE between January 1999 and May 2000. For comparison, the charts of 32 patients (32 eyes) operated on between July and December 1998 using a limbal incision (control group) were retrospectively analyzed. Outcome measures included intraoperative and postoperative complications, postoperative visual acuity, and refractive astigmatism. Results In the small-incision ECCE group, self-sealing wounds were achieved in 129 eyes (64.5%). Vitreous loss occurred in approximately 3% of eyes in both the small-incision and control groups. The final visual acuities were similar between the 2 groups, with more than 90% of eyes in both groups achieving a final best corrected visual acuity of at least 20/60. Eyes in the small-incision group had faster visual recovery ( P < .001), a lower incidence of fibrinous iritis ( P = .02), and were more likely to have round pupils ( P < .001) than eyes in the control group. The main complication of small-incision surgery was moderate corneal edema, which persisted until at least the 1-week visit in 14 eyes (7%). At the most recent visit, 1 eye in the small-incision group (0.5%) had bullous keratopathy. Conclusion In a district hospital in West Africa, small-incision manual ECCE surgery yielded faster visual rehabilitation and had a lower incidence of fibrinous iritis than standard ECCE surgery.

Surgical interventions for age-related cataract.

Cataract is the major cause of global blindness, accounting for 40 to 80% of all blindness in developing countries. The number of people blind from cataract is expected to rise due to the changing age distribution and increasing life expectancy. There is currently no proven intervention to prevent cataract and surgery is the only form of treatment. The objective of this review is to compare the effects of different surgical interventions for age-related cataract. We searched the Cochrane Controlled Trials Register - CENTRAL/CCTR, which contains the Cochrane Eyes and Vision Group specialised register (Cochrane Library Issue 3 2001), MEDLINE (1966 to August 2001), EMBASE (1980 to September 2001), the reference lists of identified trials, and we contacted investigators and experts in the field for details of published and unpublished trials. We included randomised controlled trials evaluating surgical treatment for people with age-related cataract. Two reviewers independently extracted data and discrepancies were resolved by discussion. Where appropriate, relative risks, odds ratios and weighted mean differences were summarised after assessing heterogeneity between the studies. We used a fixed effect model due to the low number of trials in each comparison. We identified six trials that randomised a total of 7828 people. Phacoemulsification gave a better visual outcome than extracapsular surgery and gave a similar average cost per procedure in one trial conducted in the UK. Extracapsular surgery with posterior chamber lens implant and intracapsular surgery with or without an anterior chamber intraocular lens implant gave acceptable visual outcomes at 12 to 24 months after surgery. In three large trials in south Asia, best-corrected visual acuity of less than 6/60 ranged from 0.5 to 4%. Higher rates of poor outcome were observed in a multicentre study with 19 surgeons compared to a single-centre study with two surgeons. This review provides evidence from one randomised controlled trial that phacoemulsification gives a better visual outcome than extracapsular extraction with sutures. However, this trial was conducted in a developed country specialised hospital setting and extrapolation to other settings must be made with caution. This review also found evidence that extracapsular cataract extraction with a posterior chamber lens implant provides better visual outcome than intracapsular extraction with aphakic glasses. This finding is also based on the results of a single trial. The long term effects of posterior capsular opacification need to be assessed in larger populations. The data in the review suggest that intracapsular extraction with an anterior chamber lens implant is an effective alternative to intracapsular extraction with aphakic glasses, with similar safety. Further data from developing regions are needed to compare all aspects of intraocular lens surgery with the three main surgical procedures - intracapsular extraction with an anterior chamber lens, extracapsular surgery with a posterior chamber lens with or without sutures.

PhacoXca™ cataract surgery

Modern cataract surgery involves removing cloudy lens cortex and nucleus through 2 openings in the eye: the capsulotomy and an incision in cornea or sclera. A new approach, PhacoXcap™, provides the ease of planned extracapsular surgery with the closed-system safety of phacoemulsification. PhacoXcap allows quick removal of the intact cortex and nucleus out of the lens bag and into the anterior chamber for iris plane phacoemulsification.

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.

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.

Simultaneous bilateral cataract extraction

Purpose To evaluate the visual outcome and safety of simultaneous bilateral cataract extraction. Setting Stobhill Hospital NHS Trust, Glasgow, United Kingdom. Methods This retrospective case review comprised 259 consecutive patients (518 eyes) who had simultaneous bilateral cataract surgery. Surgeries included bilateral extracapsular procedures, uniocular extracapsular procedures performed simultaneously with a different type of intraocular lens surgery in the other eye, and 1 bilateral intracapsular procedure. Outcome measures were postoperative best spectacle-corrected visual acuity (BSCVA), intraoperative and postoperative complication rates, and conjunctival swab culture results. Results Eighty-three percent of patients (75% of eyes) with measured preoperative and postoperative BSCVA achieved an acuity of 6/12 or better. Intraoperative and postoperative complication rates were similar to those in previous reports of unilateral extracapsular surgery and simultaneous bilateral cataract surgery. Endophthalmitis occurred in 1 eye (0.19%). There were no bilateral complications that resulted in visual loss. Cultures were positive from 42% of conjunctival swabs; 81% of positive cultures were coagulase-negative Staphylococcus and 10% were Staphylococcus aureus. Conclusions Simultaneous bilateral cataract surgery did not lead to an increased incidence of serious intraoperative or postoperative complications, and visual acuity results were good.

Small Incision Cataract Surgery and Placement of Posterior Chamber Intraocular Lenses in Patients With Diabetic Retinopathy

Diabetic patients undergoing cataract surgery have been demonstrated to have a guarded prognosis. Small incision cataract surgery has been postulated to cause fewer complications than other techniques of cataract extraction. We looked at small incision cataract surgery to see how diabetics fared. One hundred fifty-four eyes of diabetic patients were evaluated preoperatively through dilated fundus examination and Snellen visual acuity. The eyes then underwent small incision cataract surgery and were followed, undergoing periodic ophthalmoscopy, Snellen visual acuity measurement and additional postoperative therapeutic and surgical intervention. Final visual acuity improved by two Snellen lines or more in 61 out of 154 (40%) eyes. Final visual acuity worsened in 38 out of 154 (25%) eyes. Our results are similar to those reported for extracapsular surgery and phacoemulsification, suggesting that the prognosis is guarded for diabetics, even when undergoing small incision cataract surgery.

Lens epithelial cell regression on the posterior capsule with different intraocular lens materials

BACKGROUND/AIMSPosterior capsular opacification (PCO) is caused by proliferation and migration of lens epithelial cells (LECs) across the posterior capsule and is the commonest cause of reduced vision after cataract surgery....

Lens epithelial cell proliferation, migration, and metaplasia following capsulorhexis

AIMTo study the behaviour of residual lens epithelial cells after capsulorhexis and expression of material from the isolated lens.METHODSHuman and bovine lens capsules were isolated, sterile non-toxic silicone rings inserted,...

Phacoemulsification cataract surgery in vitrectomized eyes

Purpose: To determine the problems, safety, and results of phacoemulsification cataract surgery in previously vitrectomized eyes.Setting: Department of Ophthalmology of Galdacaro Hospital, Galdacano, Spain.Methods: In this prospective study, phacoemulsification was performed in 23 eyes that had had vitrectomy between February 1992 and May 1994. Surgical and postsurgical difficulties and complications and visual acuity results were analyzed. Follow-up ranged from 12 to 24 months.Results: The incidence of surgical problems and complications was higher than usual: 7 eyes presented small pupil size (<3.0 mm); sudden changes in anterior chamber depth and pupil size during surgery occurred in 6 eyes; unusual mobility and flaccidity of the posterior capsule was observed in 6 cases, which was assoc-ated with posterior subcapsular cataract and young age (<50 years). posterior capsule tear occurred in 2 eyes, 1 of which required anterior vitrectomy. Postoperatively. best visual acuity improved two Snellen lines or more in 17 eyes (73.91%), did not change in 3 (13.04%), and worsened in 3.Conclusion: Phacoemulsification in vitrectomized eyes presented more problems and complications than usual However, it seems to be safer than manual extracapsular surgery because it minimized the risk of intraoperative eye hypotony or calapse.

Cholesterol Oxides Accumulate in Human Cataracts

Human lens membranes contain the highest cholesterol content of any known biological membrane. Although cholesterol is prone to oxidation, the presence of its oxidation products in human cataract has not been shown before. This study was designed to investigate the presence of cholesterol oxides in human cataractous lenses. Human clear lenses (n=48) were obtained from Coimbra University Hospital Eye Bank. Human cataracts (n=54) were obtained by routine extracapsular surgery. Cholesterol oxides were isolated by solid-phase extraction on a C18cartridge and quantified as TMS-ether derivatives by gas chromatography. The extraction procedure allows for an efficient recovery of the major cholesterol oxides, while retaining virtually all cholesterol. Exposure of membranes isolated from transparent human lenses to the free radical generator 2,2′-Azobis(2-amidinopropane) dihydrochloride (AAPH) produced 7α-hydroxycholesterol (6%), 7β-hydroxycholesterol (19%), 5α,6a-epoxycholestanol (1%) and 7-ketocholesterol (74%) as major oxidation products. Cataractous lenses contained quantifiable amounts of 7β-hydroxycholesterol (7.3±0.74 mmol mol−1cholesterol), 7-ketocholesterol (4.2±0.32 mmol mol−1cholesterol), 5α,6a-epoxycholestanol (0.9±0.16 mmol mol−1cholesterol), 20α-hydroxycholesterol (0.6±0.13 mmol mol−1cholesterol) and 25-hydroxycholesterol (0.1±0.02 mmol mol−1cholesterol), whereas clear lenses contained no detectable amounts of cholesterol oxides. We have shown, for the first time, that oxysterols accumulate in human cataracts. Although the total amount of oxidized cholesterol in cataracts is not likely to be high it may account for much of the membrane damage associated with cataract formation.