Bo Philipson

Endophthalmitis after cataract surgery: risk factors relating to technique and events of the operation and patient history: a retrospective case-control study.

OBJECTIVE This study aimed to investigate the relationship between postoperative endophthalmitis and current changes in the cataract operative technique. DESIGN A retrospective case-control study. PARTICIPANTS The 22,091 cataract operations performed from 1990 through 1993 at St Eriks Hospital formed the basis for this investigation. In a random fashion, 220 control subjects were selected to be compared with the endophthalmitis cases. MAIN OUTCOME MEASURES Numerous variables pertaining to the cataract extraction procedure and to the ocular and general health of patients with cataracts were analyzed regarding the development of postoperative intraocular infection. Patient age, presence of diabetes or immunosuppression, type of cataract extraction and intraocular lens (IOL), and intraoperative or postoperative complications were the principal variables assessed. RESULTS Fifty-seven patients with endophthalmitis were diagnosed, resulting in an overall frequency of 0.26%. Immunosuppressive treatment (P = 0.019), wound abnormality (P = 0.03), and the use of IOLs without a heparinized surface (P = 0.0023) were the only significant risk factors found in a logistic regression model. CONCLUSIONS The results suggest that cataract operating practice may alter the risk for endophthalmitis in that implanting a heparinized IOL and creating a tight section both seem to provide protection against this dreaded complication. Regarding patient history, an increased susceptibility was found among subjects treated with immunosuppressants. Designing a prophylactic protocol that protects against endophthalmitis more efficiently than did the study prophylaxis of 20 mg of subconjunctival gentamicin, is important not only for this patient subgroup but also for the cataract operated population at large.

Normal human lens—the distribution of protein

The distribution of dry mass and protein was determined in 21 normal human lenses of different age. The lenses were obtained from enucleated tumor eyes and were immediately prepared for quantitative microradiography. The measurements were performed along the lens axis. In the anterior and posterior subcapsular cortex the dry mass content was about 0·2 g/cm 3 From this region there was an even and continuous increase over a distance of about 0·5 mm to a level of about 0·45 g/cm 3 . This level was fairly constant in the center of the lens. These results allowed a subdivision of the lens into a central lens core with a constant high concentration of dry mass and a peripheral zone with an increasing concentration from the periphery. No major changes with age in the dry mass levels could be found.

Heparin surface modified intraocular lenses. Three-month follow-up of a randomized, double-masked clinical trial.

ABSTRACT Two types of intraocular lenses (IOU) were used in a controlled, randomized, double‐masked clinical trial. The study lens was a onepiece, poly(methyl methacrylate) (PMMA) lens with heparin grafted on the entire surface. The control lens was identical in all respects but lacked the heparin surface. The IOLs were implanted in the capsular bag after extracapsular cataract extraction in 266 patients. No unexpected reactions or severe complications occurred. The postoperative visual acuity of all cases at the three‐month visit was 20/40 or better in 91.6% of the heparin group and in 86.2% of the control group. When excluding cases with preoperative pathology, 97% of the heparin group and 95% of the control group had a visual acuity of 20/40 or better. A mild iritis was observed in one case of the heparin group and in four cases of the control group at three months. At three months there was a statistically significant difference between the heparin surface modified and control IOLs for both the number of patients with cellular precipitates and the number of precipitates per IOL. From the present data we conclude that during the first three postoperative months heparin surface modified lenses are more biocompatible than PMMA lenses.

Heparin surface modified intraocular lenses implanted in the monkey eye

ABSTRACT The biocompatibility, of heparin surface modified poly(methyl methacrylate) intraocular lenses (IOLs) was evaluated in two experiments following implantation in the anterior and posterior eye chambers of adult cynomolgus monkeys. Throughout the study, large inflammatory cells and prominent pigment deposits were seen on the unmodified lenses, whereas the heparin surface modified IOLs remained almost free of precipitates. Similarly, fewer posterior svnechias were observed in eyes implanted with surface modified IOLs in the posterior chamber than in eyes implanted with control lenses. Histopathological examination of enucleated eyes confirmed the clinical findings. These experiments strongly support the idea that surface modification with heparin is a useful way to reduce clinical complications following cataract surgery with IOL implantation.

Metabolic Syndrome Components in Relation to Risk of Cataract Extraction: A Prospective Cohort Study of Women

OBJECTIVE To investigate the association between metabolic syndrome and some of its components with the incidence of cataract extraction. DESIGN Population-based prospective cohort study. PARTICIPANTS A total of 35,369 women, participating in the Swedish Mammography Cohort, aged 49 to 83 years, who completed a self-administered questionnaire about anthropometric measurements and lifestyle factors in 1997. METHODS The women were followed from September of 1997 to October of 2005. The cohort was matched with registers of cataract extraction in the study area. MAIN OUTCOME MEASURES Incident surgical extraction of age-related cataract. RESULTS We identified 4508 incident cases of cataract extractions during 98 months of follow-up. In multivariate analysis, women with a waist circumference >or=80 cm had an 8% increased risk of cataract extraction (rate ratio [RR], 1.08; 95% confidence interval [CI], 0.99-1.17). Women with diabetes had a 43% increased risk of cataract extraction (RR, 1.43; 95% CI, 1.10-1.86), and hypertension was associated with a 12% increased risk (RR, 1.12; 95% CI, 0.99-1.26). Women with all 3 components of the metabolic syndrome (waist >or=80 cm, diabetes, and hypertension) had a 68% increased risk of cataract extraction (RR, 1.68; 95% CI, 1.40-2.02) compared with women without any of these components. Among women aged less than 65 years at baseline with all 3 components of metabolic syndrome, the risk of cataract extraction was approximately 3-fold more (RR, 2.80; CI, 1.94-4.03). CONCLUSIONS Metabolic syndrome and its components, abdominal adiposity, diabetes, and hypertension, seem to be associated with an increased risk for cataract extraction, especially among women aged less than 65 years.

Incidence of endophthalmitis in Sweden

Abstract. A retrospective review of all suspected and proven cases of endophthalmitis (EO) during a period of 18 months in Sweden is presented. This period covered the time of transition in the surgical technique at a large number of clinics. Sixty‐two cases of EO were reported out of which 52 were post‐operative. A total incidence of post‐operative endopthalmitis (POE) was found to be 0.33%. The incidence of culture proven POE was however only 0.06%. No cultures or only conjunctival cultures had been taken in 32 (61.5%). S.epidermidis and S.aureus comprised the majority of isolates. No case of fungal EO was reported. The number of posttraumatic EO was low.

Risk of acute suprachoroidal hemorrhage with phacoemulsification

Purpose: To establish whether small incision cataract surgery with phacoemulsification decreases the risk of acute suprachoroidal hemorrhage (ASCH) compared with traditional nucleus expression by extracapsular cataract extraction (ECCE). Setting: St. Erik Eye Hospital, Stockholm, Sweden. Methods: A retrospective study was done on the incidence of ASCH in cataract surgery between July 1990 and July 1996. During this period, 37,565 cataract extractions (phacoemulsification and ECCE) were performed at St. Erik Eye Hospital, combined procedures excluded. The criteria for diagnosis were the suspicion of ASCH during surgery and a verified diagnosis via an expulsive hemorrhage into the wound (4 cases), postoperative ultrasonic examination (20 cases), or a choroidal mass on performing ophthalmoscopy together with a postoperative history alluding to the diagnosis (2 cases). Results: Twenty‐six eyes were identified with ASCH, including 7 during phacoemulsification and 19 during ECCE. The incidence of ASCH was 0.03% in the 23,213 phacoemulsification cases and 0.13% in the 14,352 ECCE cases. The difference was statistically significant (P = .0003; chi‐square test). Conduslon: Small incision surgery with phacoemulsification decreased the risk of ASCH in cataract surgery compared with the traditional nucleus expression technique.

Microdensitometer system for microradiography

SummaryA microdensitometer system for point measurements in areas down to a few square micrometers is described. The detector system is connected to an integrating digital voltmeter, constituting a very sensitive system. The digital output signals and a digital identification are registered on a recorder and on a tape punch, thus facilitating computer analysis.The precision of the equipment varied from ∼1.1 per cent, for low signal levels, to ∼0.3 percent for the highest signal levels. Stray light, the only important source of systematic errors, was found to influence the output signal level. Concerning determinations of the densities, however, a variation of the order of 1 per cent was only obtained for small areas with densities differing from that of the background.

Heparin surface modified intraocular lenses - a one-year follow-up of a safety study

Abstract PMMA intraocular lenses have been modified by bonding a monolayer of Heparin molecules to the surface. These Heparin surface modified (HSM) IOLs were implanted in the capsular bag after extracapsular cataract extraction. Sixty‐six patients were followed for 12 months in an open safety study. No unexpected reactions or severe complications occurred. Eighty‐nine per cent of the patients obtained a visual acuity (VA) of 0.5 or more at the 12‐month visit. When excluding cases with pre‐operative pathology only one case (1.5%) had less VA than 0.5. A mild postoperative iritis was seen during the first week after surgery, and in only three cases at a later visit. Cell precipitates were seen in a small number of cases. From this study and from earlier in vitro and in vivo animal studies we draw the conclusion that the Heparin surface modified IOLs are safe for implantation in human eyes.

Unscheduled DNA synthesis in lens epithelium after in vivo exposure to UV radiation in the 300 nm wavelength region

Abstract A quantitative autoradiographic method was developed to study the pattern of DNA synthesis in the rat lens epithelium after in vivo exposure to UV radiation in the 300 nm wavelength region. It was found that UV radiation (peak transmission = 298 nm, half‐width = ± 10 nm) induces unscheduled DNA synthesis and that the proportion of nuclei in S‐phase concurrently is reduced indicating an inhibition of the scheduled DNA synthesis. The registered unscheduled DNA synthesis is believed to be excision repair of DNA damage induced by the UV radiation. Excision repair in lens epithelial cells could be one mechanism involved in the correlation between exposure to sunlight and cataracts.