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This review summarizes data collected by the Swedish National Cataract Register (NCR), which by the end of 2022 contained data on more than 2.6 million cataract surgeries between 1992-2022. During these 31 years, the cataract surgery rate (CSR) rose from 3 700 to 14 407. The coverage of NCR is very high, including 93% of all cataract procedures in Sweden during the last decade. A clear trend is that the procedure is performed in eyes with increasingly high visual acuity. The proportion of patients with Snellen 0.5 or worse in the first eye at surgery has decreased from 88% in 2007 to 69% in 2022. Patient Reported Outcome Measures (PROM) have been registered with the Catquest-9SF questionnaire since 2008, demonstrating stable favorable outcomes. Surgical complications have decreased; endophthalmitis has decreased from 0.10% to below 0.02%, and posterior capsule rupture from 2.8% to 0.6%.

Purpose: To evaluate the performance of different probabilistic classifiers to predict posterior capsule rupture (PCR) prior to cataract surgery., Methods: Three probabilistic classifiers were constructed to estimate the probability of PCR: a Bayesian network (BN), logistic regression (LR) model, and multi-layer perceptron (MLP) network. The classifiers were trained on a sample of 2 853 376 surgeries reported to the European Registry of Quality Outcomes for Cataract and Refractive Surgery (EUREQUO) between 2008 and 2018. The performance of the classifiers was evaluated based on the area under the precision-recall curve (AUPRC) and compared to existing scoring models in the literature. Furthermore, direct risk factors for PCR were identified by analysing the independence structure of the BN., Results: The MLP network predicted PCR overall the best (AUPRC 13.1 ± 0.41%), followed by the BN (AUPRC 8.05 ± 0.39%) and the LR model (AUPRC 7.31 ± 0.15%). Direct risk factors for PCR include preoperative best-corrected visual acuity (BCVA), year of surgery, operation type, anaesthesia, target refraction, other ocular comorbidities, white cataract, and corneal opacities., Conclusions: Our results suggest that the MLP network performs better than existing scoring models in the literature, despite a relatively low precision at high recall. Consequently, implementing the MLP network in clinical practice can potentially decrease the PCR rate., (© 2023 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

The present review summarizes data collected by the Swedish National Cataract Register (NCR), which by the end of 2021 contained data for more than 2.4 million cataract surgeries between 1992 and 2021. During these 30 years, the cataract surgery rate rose from 3700 to 12 800. The coverage of NCR is very high including 93% of all cataract procedures in Sweden between 2010 and 2021. Independently of demographic changes, the proportion of operations of patients age 60 to 79 has increased while the proportion of 80 to 90+ has decreased. The median visual acuity of the first eye planned for surgery was 0.1 decimal in 1992 and has increased to 0.5 decimal in 2021. Patient-reported outcome measures have been registered with the Catquest-9SF questionnaire since 2008, demonstrating intervention at an earlier stage, but consistently favorable outcomes. Surgical complications have decreased; endophthalmitis has decreased from 0.10% to below 0.02%, and posterior capsule rupture from 2.8% to 0.6%., (Copyright © 2023 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To determine the trends in anesthesia techniques for cataract surgery over the past decade and their relationship to surgical complications., Setting: Clinics affiliated with the European Registry of Quality Outcomes for Cataract and Refractive Surgery (EUREQUO)., Design: Retrospective cross-sectional register-based study., Methods: Variables include patient demographics, visual acuity, ocular comorbidities, surgery characteristics, intraoperative complications, and postoperative complications for the study period from January 2008, to December 2018. The anesthesia methods registered in the EUREQUO and included in the study are topical, combined topical and intracameral, sub-Tenon, regional, and general anesthesia. Multivariate logistic regression models for each complication were constructed to estimate the adjusted odds ratio (OR) and 95% CIs., Results: Complete data were available of 1 354 036 cataract surgeries. Topical anesthesia increased significantly over time (from 30% to 76%, P < .001). Sub-Tenon and regional anesthesia decreased (from 27% and 38% to 16% and 6%, respectively, P < .001), and general and combined topical and intracameral anesthesia remained stable (around 2%). Sub-Tenon (OR, 0.80; 95% CI, 0.71-0.91, P < .001), regional (0.74; 95% CI, 0.71-0.78, P < .001), general (0.53; 95% CI, 0.50-0.56, P < .001), and intracameral anesthesia (0.76; 95% CI, 0.64-0.90, P = .001) carried a significantly decreased risk of posterior capsule rupture (PCR), with and without dropped nucleus, compared with topical anesthesia. The risk of endophthalmitis was significantly lower with regional anesthesia compared with topical anesthesia (OR, 0.60; 95% CI, 0.44-0.82, P = .001)., Conclusions: The use of topical anesthesia for cataract surgery increased over time. Topical anesthesia is associated with an increased risk of PCR with and without dropped nucleus, and endophthalmitis., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of ASCRS and ESCRS.)

Purpose: To analyze the outcomes of cataract surgery complicated by posterior capsule rupture (PCR)., Setting: European clinics affiliated to the European Registry of Quality Outcomes for Cataract and Refractive Surgery (EUREQUO)., Design: Retrospective cross-sectional register-based study., Methods: Data were retrieved from the EUREQUO between January 1, 2008, and December 31, 2018. The database consists of data on demographics, intraoperative complications such as PCR, type of intraocular lens (IOL) material, postoperative refraction, corrected distance visual acuity (CDVA), and postoperative complications., Results: 1 371 743 cataract extractions with complete postoperative data were reported in the EUREQUO. In 12 196 cases (0.9%), PCR was reported. After PCR, patients were more likely to receive a poly(methyl methacrylate) IOL (5.2% vs 0.4%, respectively) or no IOL (1.1% vs 0.02%, respectively) compared with patients without PCR. The refractive and visual outcomes in patients with PCR were significantly worse than in those without PCR (mean CDVA 0.13 ± 0.21 vs 0.05 ± 0.16 logMAR, P < .001; mean absolute biometry prediction error 1.15 ± 1.60 diopters [D] vs 0.41 ± 0.45 D, P < .001). A multivariate linear regression analysis, adjusting for potential explanatory variables, confirmed a statistically significant difference (0.04 logMAR, P < .001, and .70 D, P < .001, respectively). Patients with PCR had significantly more postoperative complications (corneal edema 0.88% vs 0.17%, adjusted odds ratio [aOR], 2.80 95% CI, 2.27-3.45, endophthalmitis 0.11% vs 0.02%, aOR, 4.40 95% CI, 2.48-7.81, uncontrolled intraocular pressure 0.55% vs 0.03%, aOR, 14.58 95% CI, 11.16-19.06, P < .001)., Conclusions: Patients with PCR had significantly worse visual and refractive outcomes and more postoperative complications than patients without PCR. However, most of these patients achieved better postoperative visual acuity than that preoperatively., (Copyright © 2022 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To analyze the incidence and risk factors for posterior capsule rupture (PCR) in cataract surgery., Setting: European clinics affiliated with the European Registry of Quality Outcomes for Cataract and Refractive Surgery (EUREQUO)., Design: Retrospective cross-sectional register-based study., Methods: Data were obtained from the EUREQUO. The database contains data on demographics, comorbidities, and intraoperative complications, including PCR for the study period from January 1, 2008, to December 31, 2018. Univariate and multivariate logistic regression analyses were performed to estimate the (adjusted) odds ratio (OR) and 95% confidence intervals (CIs)., Results: We analyzed EUREQUO registry data of 2,853,376 patients, and 31,749 (1.1%) cataract surgeries were complicated by a PCR. Data were available of 2 853 376 patients, and 31 749 (1.1%) cataract surgeries were complicated by a PCR. The PCR rate ranged from 0.60% to 1.65% throughout the years, with a decreasing trend (P < .001). The mean age of the PCR cohort was 74.8 ± 10.5 years, and 17 29 (55.5%) patients were female. Risk factors most significantly associated with PCR were corneal opacities (OR 3.21, 95% CI, 3.02-3.41, P < .001), diabetic retinopathy (OR 2.74, 95% CI, 2.59-2.90, P < .001), poor preoperative visual acuity (OR 1.98, 95% CI, 1.88-2.07, P < .001), and white cataract (OR 1.87, 95% CI, 1.72-2.03, P < .001)., Conclusions: Risk factors for PCR were identified based on the EUREQUO, and the incidence of this complication is decreasing over time., (Copyright © 2021 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To study practice patterns in European cataract surgery over a 10-year period., Setting: European clinics affiliated to the European Registry of Quality Outcomes for Cataract and Refractive Surgery (EUREQUO)., Design: Registry cohort study., Methods: The EUREQUO contains preoperative, intraoperative, and postoperative parameters reported by surgeons in many European clinics. All data reported to the registry are anonymized. Preoperative parameters included age, sex, visual acuity, target refraction, ocular comorbidity, and surgical difficulties. Surgical data included anesthesia, surgical technique, intraocular lens optic biomaterial, and complications. Postoperative parameters included visual acuity, refraction, and short-term complications., Results: During the study period (January 1, 2008, to December 31, 2017), a total of 2 714 108 cataract extractions were reported to the EUREQUO. Preoperative data changed over time, with decreases in mean age (74.5-73.0 years), proportion of women from 60.6% (100 373/165 628) to 57.2% (174 908/305 845), and proportion of coexisting eye diseases from 30.0% (49 638/165 650) to 27.0% (82 704/305 846) and with improvements in preoperative visual acuity (mean logarithm of minimum angle of resolution [logMAR] 0.46 to 0.37). The use of topical anesthesia increased over time from 28.1% (26 238/93 320) to 71.7% (130 525/182 083). Surgical complications showed a significant decrease from 2.5% (4107/165 650) to 1.2% (3573/305 846). The visual outcome improved over time (mean logMAR 0.08 to 0.05), as did the absolute median prediction error (0.38 diopter [D] to 0.28 D)., Conclusions: Trends in European cataract surgery practice patterns from 2008 to 2017 have moved toward younger patients with better preoperative visual acuity, fewer surgical complications, and better predicted refractions and visual outcomes., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of ASCRS and ESCRS.)

Purpose: To explore the frequency and outcomes of cataract surgery in eyes with previous vitrectomy., Setting: Fifteen European countries., Design: Retrospective cross-sectional register-based study., Methods: The European Registry of Quality Outcomes of Cataract and Refractive Surgery (EUREQUO) contains data on baseline characteristics, surgery, and follow-up for cataract surgeries. Previous vitrectomy is included as a mandatory parameter in baseline characteristics. According to the protocol for EUREQUO, consecutive cases should be reported by participating units., Results: This study included data from units in 15 European countries from 2008 to 2018; 1 715 348 cataract extractions with follow-up data were reported to EUREQUO. Previous vitrectomy was reported in 19 416 eyes comprising 1.1% of all cases. This proportion was about the same for each study year. Most patients were men, and their mean age was 64.1 years compared with 73.7 years for the rest of the database. The preoperative visual acuity was modestly worse in postvitrectomy eyes compared with the opposite (corrected distance visual acuity [CDVA] 0.45 vs 0.25, respectively). A postoperative CDVA of 0.5 or better was achieved by 82.8% of the postvitrectomy eyes compared with 95.6% for the non-postvitrectomy eyes. The absolute mean biometry prediction error for the same groups was 0.52 diopters (D) vs 0.43 D, respectively., Conclusions: Patients undergoing cataract extraction after previous vitrectomy were younger and mostly men. Their visual and refractive outcomes were slightly inferior compared with the patients without vitrectomy.

Purpose: The aim of this study was to describe changes over time in the indications and outcomes of cataract surgery and to discuss optimal timing for the surgery., Design: Database study., Participants: Patients who had undergone cataract extraction in the Netherlands, Sweden, or Malaysia from 2008 through 2012., Methods: We analyzed preoperative, surgical, and postoperative data from 2 databases: the European Registry of Quality Outcomes for Cataract and Refractive Surgery (EUREQUO) and the Malaysian National Cataract Registry. The EUREQUO contains complete data from the national cataract registries in the Netherlands and Sweden., Main Outcome Measures: Preoperative and postoperative corrected distance visual acuity, preoperative ocular comorbidity in the surgery eye, and capsule complications during surgery., Results: There were substantial differences in indication for surgery between the 3 national data sets. The percentage of eyes with a preoperative best-corrected visual acuity of 20/200 or worse varied from 7.1% to 72%. In all 3 data sets, the visual thresholds for cataract surgery decreased over time by 6% to 28% of the baseline values. The frequency of capsule complications varied between the 3 data sets, from 1.1% to 3.7% in 2008 and from 0.6% to 2.7% in 2012. An increasing postoperative visual acuity was also seen for all 3 data sets. A high frequency of capsule complication was related significantly to poor preoperative visual acuity, and a high frequency of decreased visual acuity after surgery was related significantly to excellent preoperative visual acuity., Conclusions: The 5-year trend in all 3 national data sets showed decreasing visual thresholds for surgery, decreasing surgical complication rates, and increasing visual outcomes regardless of the initial preoperative visual level. Cataract surgery on eyes with poor preoperative visual acuity was related to surgical complications, and cataract surgery on eyes with excellent preoperative visual acuity was related to adverse visual results., (Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to use the Catquest-9SF to measure cataract surgery outcomes, and to use Rasch analysis to test the psychometric properties of this questionnaire, including its validity and responsiveness., Methods: Patients were recruited as consecutive cataract surgery patients during 1 month at six surgical units in Sweden (via the National Cataract Register). The patients completed the questionnaire before surgery and 3 months after. The Catquest-9SF data were assessed for fit to the Rasch model using version 3.63.2 of the WINSTEPS software (Winsteps.com, Beaverton, OR, USA). Both preoperative and postoperative questionnaires were included in the analysis. The responsiveness to cataract surgery was calculated as the effect size., Results: Completed questionnaires before and after surgery were received from 846 patients. The Rasch analysis showed that the category thresholds were ordered. All items fit a single overall construct (infit range 0.79-1.40; outfit range 0.74-1.40). The ability to discriminate different strata of person ability was good, with a real patient separation of 2.58 and patient separation reliability of 0.87. The questionnaire showed unidimensionality and was largely free from differential item functioning. The item difficulty was reasonably well targeted to both preoperative and postoperative patient ability. The Catquest-9SF Rasch score correlated significantly with visual acuity, and cataract surgery resulted in a significant improvement with an effect size of 1.8., Conclusion: The Catquest-9SF shows excellent psychometric properties, as demonstrated by Rasch analysis. It is highly responsive to cataract surgery, and its brevity (nine items) makes it well suited for use in daily clinical practice., (© 2009 The Authors. Journal compilation © 2009 Acta Ophthalmol.)

This review summarizes data collected by the Swedish National Cataract Register, which now contains data pertaining to more than a million cataract surgery procedures, representing 95.6% of the surgeries performed in Sweden during 1992-2009. During this period, the rate of cataract surgery rose from 4.47 to 9.00 per 1000 inhabitants. The mean patient age increased until 1999 but has slowly decreased since then. Preoperative visual acuity has risen steadily. The distribution between the sexes was stable until 2000, after which the proportion of women slowly decreased. Registration of subjective benefit has brought new knowledge regarding indications and expectations. An improved questionnaire, Catquest-9SF has been used since 2008. The outcome register generally shows good results from the surgery. Endophthalmitis has decreased from 0.10% to below 0.040%., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate whether posterior capsule opacification (PCO) morphology, visual acuity (VA) and self-assessed visual function correlate, and to compare perceived visual disabilities with those of cataract patients with corresponding VA., Methods: Twenty-one patients with PCO were examined before capsulotomy. In adjunct to the ophthalmological examination, the patients completed a Catquest questionnaire and a digitized retroillumation image was acquired. The images were analysed with the Evaluation of Posterior Capsule Opacification (EPCO) program. Data for visual function were compared with data from the National Swedish Cataract Register (NCR)., Results: The epco values were correlated with VA in the PCO eyes: the higher the epco score, the lower the VA. There were also correlations between the epco scores, satisfaction with vision, and perceived disabilities in daily life. Symptoms of glare were not significantly correlated with epco scores or with VA. Visual acuity in PCO eyes was better correlated with perceived disabilities and satisfaction with vision than VA in eyes with cataract., Conclusions: There was a significant correlation between epco scores and VA and between epco scores and Catquest. Consequently, the morphological method was related to the self-assessed visual function. Patients with PCO seemed to have more disturbed visual function, as defined by Catquest, than cataract patients with the same VA.

Purpose: To describe the functional outcome, as defined using the Catquest questionnaire, for patients with posterior capsule opacification (PCO) after capsulotomy., Methods: A total of 47 patients with PCO were examined before and 1 month after capsulotomy. In addition to the ophthalmic examination, Catquest was completed and a digital image of the posterior lens capsule acquired., Results: Capsulotomy resulted in a good level of benefit, as defined using Catquest, for 77% of the patients. No subgroup of patients who derived an exceedingly good or poor level of benefit was identified. Disabilities in daily life, satisfaction with vision and symptoms of glare improved from treatment (p < 0.001, p < 0.001 and p = 0.002, respectively). The results were comparable with the benefits of cataract surgery., Conclusions: Self-assessed visual function as defined using Catquest improved after capsulotomy for the vast majority of patients with PCO. No group of patients with exceptionally good or poor levels of benefit could be identified with certainty. However, the majority of those with a poor outcome were elderly individuals with ocular comorbidity. The overall functional results from treatment of PCO were very similar to those achieved after cataract surgery.

Purpose: To compare posterior capsule opacification (PCO) after cataract surgery with implantation of two silicone intraocular lenses (IOLs) with different designs., Methods: We carried out a prospective, clinical study of 116 patients randomized to standardized phacoemulsification with implantation of CeeOn Edge (n = 57) or SI40NB (n = 59) IOLs. The follow-up period was 3 years. To evaluate PCO morphologically, digital images were obtained and analysed using evaluation of posterior capsule opacification computer software (epco). The neodymium:YAG (Nd:YAG) capsulotomy rate was recorded., Results: At 2 and 3 years, the eyes with SI40NB IOLs had significantly more PCO than those with the CeeOn Edge IOLs (p = 0.00014 and p = 0.002). Nine Nd:YAG capsulotomies were performed in the SI40NB group and none in the CeeOn Edge group. This difference was statistically significant (p = 0.003). In some patients a regression of PCO was noticed and confirmed using epco. Statistically less PCO was noted when the capsulorhexis rim was placed so that it covered all 360 degrees of the optic of the IOL., Conclusions: A clinically and statistically significant difference in PCO development between CeeOn Edge and SI40NB IOLs at 2 and 3 years postoperatively was found. These findings support earlier studies indicating that a sharp edge of the optic is a more important factor in IOL design than IOL material in the prevention of PCO.

The Swedish National Cataract Register (NCR) has been collecting data on cataract extractions in Sweden since 1992. This unique national database now contains data pertaining to more than 400 000 operations, representing 93.4% of all operations performed nationwide during 1992-2000. Clinic participation in the NCR is voluntary. Tests have shown NCR data to be extremely reliable, while the participation of nearly all providers of cataract surgery in Sweden makes the data highly representative of cataract surgery throughout the country. The NCR collects pre- and per-operative data for every cataract extraction performed at participating clinics. Surgical outcome data and data about patients' self-assessed visual function is collected in approximately 10% of cases. Since 1998, all cases of suspected postoperative endophthalmitis have also been reported to the NCR. The rate of surgery has increased from 4.47 to 7.26 per 1000 inhabitants during the period. Female subjects have constituted about 66% of all operated subjects each year and the mean age of patients has slowly increased from 75.2 to 76.1 years. Average pre-operative visual acuity has improved each year. Second eye surgery has increased from 28.5% to 36.8% of all surgeries. Phacoemulsification has reached 98% as type of surgery (in 2000) and 92.7% of all intraocular lenses are foldable. Surgical outcome has improved by achieving a final refraction closer to the target refraction and less surgically induced astigmatism. The positive impact of cataract surgery in very elderly people has been demonstrated, as has the positive effect of second eye surgery, especially in young subjects. The NCR has served to enhance knowledge about trends and results of cataract surgery in Sweden. This review article describes some of the activities carried out and their results.

Purpose: A Swedish National Cataract Register was instituted in 1992, monitoring nearly all cataract operations in Sweden, and since its inception comprising about 95% of all operations. Data from a total of approximately 290 000 operations have been collected during 1992-1998. Data quality is an important factor, and we have therefore assessed the various types and frequencies of data entry errors in the material., Methods: The medical records for all operations in five selected participating clinics were retrieved for a set month. Each data transfer step from the record to the final data base was monitored for a total of 574 operations. A total of 10 variables were recorded for each operation., Results: Significant sources of error were absent in most variables. However, possibly important errors appeared in three: "date entering waiting list", "preoperative best corrected visual acuity in the operated eye", or "visual acuity in the fellow eye". There were also noteworthy variations between the five clinics, different for different parameters. Errors were predominantly prone to appear at the very first step of registration. In most cases this was due to deviations from the data collection instructions., Conclusions: The reliability is good for most values entered into the register, but it is important to ensure that data definitions are exact and adhered to. Repeated information to the involved persons on how to fill in the forms appears to be a requisite for maintaining good input quality.

Purpose: To collect clinical data on cataract surgery to allow participating surgeons to compare their performance with that of their colleagues in an anonymous manner., Setting: Surgeons from 31 surgical units providing cataract surgery in 13 European countries., Methods: Every patient at each participating unit having surgery during 1 study month was evaluated. Data were reported to the coordinating center at the time of surgery and at the final examination. When the study was closed 6 months after surgery, all participants were provided with the outcomes from their own patients so they could compare them with outcomes from other centers., Results: The study included preoperative and intraoperative data on 2950 patients. Complete follow-up data were available for 2731 patients. The surgical audit included surgically induced astigmatism, proximity of target refraction, and the frequency of major complications. For each variable, a large variation in outcome between participating centers was found. Most centers had results both above and below average for different variables., Conclusion: Cataract surgery data collected from 31 units in 13 European countries allowed participants to compare their performance with that of their colleagues in an anonymous manner. Significant variation was found in the outcomes among the units, with many units reporting results above and below the averages.

Purpose: To describe the cost for society services caused by the patients awaiting surgery for one year in Gothenburg, 1997., Methods: From a waiting list of 1458 patients awaiting cataract surgery 250 randomly selected patients were interviewed. The structured questions focused on community services, such as home help, subsidised travel by taxi, medical treatment at home, visual aids, hospital stay and medical consultation, caused by the cataract symptoms., Results: The total cost for the community for the 1458 patients awaiting surgery was an estimated SEK 5,200,000. Hospital stay and home help were the largest parts of this community expense., Conclusion: The direct costs for society for one year caused by 1458 patients awaiting cataract surgery with a mean waiting time of 9.8 months was approximately the same as operating 800 patients (eyes).

Purpose: To study the gender difference in total utilisation of cataract surgery in Sweden during the years 1992-1997., Methods: The study is based on data from the National Swedish Cataract Register which covers about 95% of all cataract operations performed in Sweden during the study period., Results: Utilisation of cataract surgery in Sweden was significantly higher in females than in males for all age groups between 50 and 89 years of age during the period 1992-1997. This gender difference was more pronounced for second eye surgery than first eye surgery in most age groups. The gender difference varied also depending on the pre-operative visual acuity., Conclusion: The cataract surgery rate was significantly higher for females compared to males during the study period. Three hypotheses to explain the gender difference are discussed.

Aims: Cataract surgery has at times been said to correlate with an increased death risk. We have therefore analysed the standardised death ratio in a population based cohort of patients that had undergone cataract surgery., Methods: Data for all patients undergoing cataract surgery from 1986 up to and including 1990 in the Lund Health Care District were prospectively recorded, and 5120 were retrieved for analysis. Death dates and primary death diagnoses for each patient were obtained from the Swedish Bureau of Census up to and including 1991. Standardised mortality ratios were calculated for all patients, subdivided into a number of categories: inpatients, outpatients, sex, age < 75 years, age > or = 75 years, patients with heart and circulatory diseases, with malignant tumours, and with diabetes. The cut off age was set at 74 because this divided the patients into two approximately equal groups. Using time dependent survival regression, the relative risk for dying were estimated for sex, age, and for postoperative YAG laser capsulotomy, and also for diabetic patients and patients with rheumatoid arthritis., Results: Inpatients almost always show an increased standardised mortality ratio compared with outpatients. Young patients and diabetic patients also showed an increased standardised mortality ratio, compared with the normal population, but not older patients, who constitute the majority. Cardiovascular death diagnoses were overrepresented among the young., Conclusions: Cataract surgery is correlated with an increased standardised mortality ratio only in young patients and in patients with certain complicating diseases like diabetes and cardiovascular diseases.

In 1992 a Swedish National Cataract Register was instituted. More than 90% of all cataract surgeries are performed at community run eye clinics. All community run eye clinics in the country participated and 89% of all cataracts performed are included in this register. In total 31,679 eyes were entered. All the pertinent preoperative information on these patients can be found in the register. As indicated in other studies two-thirds of the surgeries were performed on women and one-third of the surgeries was performed on second eyes. The number of surgeries equals 4.5 per 1000 inhabitants and this figure has steadily increased since 1980.

With the Cataract Analysis System (CAS) we have analyzed 5.878 consecutive patients undergoing cataract operations from 1986 through 1990. The material is complete enough to be regarded as representative of the cataract surgery performed in the Lund Health Care District cataract surgery referral region during this period. There has been a striking increase in the number of operations, in 1990 reaching 3.6 per 1000 inhabitants in the referral region. A number of demographic factors have been analyzed previously, and the preoperative status of the patients is reported in this paper. In 1986, the cataract patients showed more visual impairment than in 1990, but the average age at surgery did not change between the years. We therefore suggest that the increase in the number of patients which were operated on represents a new category that was added. During the period, the planned refraction has changed towards emmetropia, presumably reflecting several kinds of improvements in the procedure. About 78 per cent of the population had a preoperative astigmatism < 1.5 D. As expected males had slightly longer eyes than women, and their corneal curvature was also slightly less.

With the Cataract Analysis System (CAS) we have analyzed 5878 consecutive cataract patients operated from 1986 through 1990. The material is complete enough to be regarded as representative of the cataract surgery performed in the entire referral region of the Lund Health Care District during this period. There has been a striking increase in the number of operations, in 1990 reaching 3.6 per 1000 inhabitants in the referral region. Simultaneously, surgery has changed from being mainly an in-patient to an out-patient procedure. Females predominate in the material, also after adjustment for the female preponderance in the population. Most likely, this is due to a higher incidence of cataract in women than in men.