Straylight in anterior segment disorders of the eye

This thesis describes new insights in the role of clinical straylight measurements in patients with ocular anterior segment disorders. Ocular straylight involves the fraction of the incoming light that is scattered by the ocular media. It does not contribute to the normal retinal image formation, but generates a rather homogeneous haze over the entire retina instead. This leads to a decrease in quality of the retinal image and complaints of hazy vision, increased glare hindrance and loss of colour and contrast perception. Ocular straylight is a comparatively new factor to be taken into consideration in clinical practice. It has been studied for years in experimental and laboratory settings and recently a survey paper has appeared. The concept of straylight fills a gap in the evaluation of patients with visual complaints, as straylight measurements are able to translate subjective complaints into quantifiable and reproducible results which provide a valuable contribution to visual tests already in use. The aims of this thesis were to study 1) the influence of the healthy and diseased anterior ocular segment on the amount of straylight and 2) which contributions straylight measurements can make in the diagnostic and therapeutic process of several corneal and lenticular disorders, in relation to the commonly accepted and universally used visual function measures such as visual acuity and slitlamp evaluation. The studies in this thesis provide additional insights in the clinical relevance of straylight measurements in a multifold of diseases and disorders which can be encountered in the practice of an ocular anterior segment surgeon

Straylight in posterior polar cataract

Purpose: To study straylight before and after posterior polar cataract removal. Setting: Academic Medical Center, Amsterdam, the Netherlands. Design: Prospective case series. Methods: Patients diagnosed with posterior polar cataract who agreed to cataract surgery were included in the study. Intraocular straylight was measured before and after surgery with the compensation comparison method using a straylight meter (C-Quant). Results: Measurements were performed on 8 eyes of 4 patients. The mean preoperative corrected distance visual acuity was relatively good (0.15 logarithm of the minimum angle of resolution [logMAR] ± 0.18 (SD). The mean postoperative CDVA was −0.08 ± 0.09 logMAR (P <.01). The mean preoperative straylight was extreme (2.01 ± 0.38 log[s]), 13 times that of a young normal eye; however, it improved postoperatively to 1.04 ± 0.26 log(s) (P <.01). Conclusions: Straylight in eyes with posterior polar cataract patients can be extremely bothersome, while visual acuity is relatively well preserved. Surgery was effective in lowering straylight levels. For these patients, straylight measurements can help objectively measure the quality of vision complaints, and elevated straylight levels can be an indication for surgery independent of visual acuity

Multifocal intraocular lens implantation after previous hyperopic corneal refractive laser surgery

Purpose: To describe the outcomes in terms of the refraction and visual acuity of multifocal intraocular lens (IOL) implantation in patients with previous hyperopic corneal refractive laser surgery. Setting: Academic Medical Center, University of Amsterdam, Amsterdam, and Retina Total Eye Care, Driebergen, the Netherlands. Design: Retrospective case series. Methods: Results were analyzed 3 months after implantation of a multifocal IOL (Acrysof Restor SN6AD1) in patients after previous corneal refractive laser surgery for hyperopia. The primary outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and refraction. The secondary outcome measures were the number of laser enhancements and posterior capsule opacification (PCO) rates. Results: Forty eyes of 40 patients were included. Sixteen eyes (40.0%) had lens extraction because of cataract, and 24 eyes (60.0%) had refractive lens exchange. The mean postoperative UDVA was 0.16 logarithm of the minimum angle of resolution (logMAR) ± 0.18 (SD), and the mean postoperative CDVA was 0.01 ± 0.08 logMAR. The mean postoperative spherical equivalent was 0.04 ± 0.92 diopter (D). Twenty-five eyes (62.5%) were within ±0.50 D of emmetropia, and 35 eyes (87.5%) were within ±1.0 D of emmetropia. Nine eyes (22.5%) had a laser enhancement because of a residual refraction error. Eleven eyes (27.5%) had a neodymium:YAG laser capsulotomy because of PCO. Conclusions: In general, multifocal IOL implantation after corneal refractive laser surgery for hyperopia resulted in good visual acuity and refraction. The magnitude of previous hyperopia did not influence the refractive predictability

Multifocal intraocular lens implantation after previous corneal refractive laser surgery for myopia

Purpose: To describe the refraction and visual acuity outcomes of multifocal intraocular lens (IOL) implantation in patients with previous corneal refractive laser surgery for myopia. Setting: Academic Medical Center, University of Amsterdam, Amsterdam, and Retina Total Eye Care, Driebergen, the Netherlands. Design: Retrospective cohort study. Methods: The 3-month results after implantation of a multifocal IOL (Acrysof Restor) in patients who had corneal refractive laser surgery for myopia were analyzed. The primary outcome measures were corrected distance visual acuity, uncorrected distance visual acuity (UDVA), and refraction. The secondary outcome measures were number of laser enhancements, corneal irregularity, pre-laser magnitude of myopia, and posterior capsule opacification (PCO) rate. Results: Seventy-seven eyes of 43 patients were included. Twenty-nine eyes had lens extraction because of cataract, and 48 eyes had a refractive lens exchange. The mean postoperative UDVA was 0.14 logarithm of minimum angle of resolution +/- 0.22 (SD). The mean postoperative spherical equivalent was -0.38 +/- 0.78 diopter (D). Fifty-seven percent of eyes were within +/- 0.50 D of emmetropia, and 86% were within +/- 1.0 D. Sixteen eyes (20.8%) had laser enhancement because of residual refraction. Fourteen eyes (18.2%) had a neodymium:YAG laser capsulotomy because of PCO. Eyes with pre-laser myopia greater than 6.0 D had a less predictable outcome than eyes with pre-laser myopia less than 6.0 D (P = .026). Conclusions: Multifocal IOL implantation after corneal refractive laser surgery for myopia resulted in good visual acuity and refraction. Results were less predictable with myopia greater than 6.0 D. (C) 2017 ASCRS and ESCR

Age-related risk factors, culture outcomes, and prognosis in patients admitted with infectious keratitis to two Dutch tertiary referral centers

PURPOSE: To assess age-related risk factors (RFs), microbiologic profile, and prognosis of infectious keratitis and create guidelines for prevention and treatment. METHODS: Retrospective review of patients with infectious keratitis admitted to 2 Dutch tertiary referral centers from January 2002 to December 2004. RESULTS: Forty-nine patients were admitted to the Academic Medical Center (Amsterdam) and 107 to the Rotterdam Eye Hospital. Mean age was 56.6 +/- 24.4 (SD) years; 49.4% were >or=60 years of age. The most common RFs among the elderly were systemic illness (36.4%), ocular surgery (33.8%), topical steroids (26%), blepharitis (20.8%), and herpetic eye disease (28.6%). This was significantly different from the most common RFs among younger patients (contact lens wear, 62.7%; chi2, P = 0.000). Gram-negative infections predominated (52.3%) and were more prevalent among younger patients (chi2, P = 0.000). Gram-positive infections prevailed among the elderly. Untreated patients had higher culture positive rates (68.7%) than patients treated with antibiotics before culturing (41.3%; chi2, P = 0.001). Elderly patients had a higher risk of perforations than younger patients (27.6% vs. 9.9%), a worse prognosis (mean VA, 6/30 vs. 6/10), and more often needed surgery (57.1% vs. 23.4%; P < 0.005 in all cases). CONCLUSIONS: Infectious keratitis is a more severe disease in elderly than in younger patients with more complications and a worse prognosis. Elderly patients have multiple and more diverse risk factors, making prevention difficult. Prevention should aim at minimizing topical steroid use and controlling blepharitis, ocular surface disease, and herpetic eye disease. Initial antibiotic treatment should include sufficient coverage of Gram-positive pathogen

Intraocular pressure after descemet stripping endothelial keratoplasty (DSEK)

To assess the incidence of elevated intraocular pressure (IOP) after descemet stripping endothelial keratoplasty (DSEK). Retrospective case series. From the start of the technique in our hospital in 2003 until the middle of 2010, 73 eyes underwent DSEK, of which 66 (90.5 %) had a clear graft 1 year after surgery. IOP data pre- and postoperatively were analyzed. Follow-up was 1-5 years (mean 3.8, SD 1.3). Mean age was 71 years (SD 11, range 43-89). Three eyes (4.5 %) had a history of glaucoma before DSEK. Mean pre-operative IOP was 12.4 mmHg (SD +/- A 4.3). Mean IOP 1 day post-operatively was 16.4 mmHg (+/- 9.2). Mean IOP after 1 and 6 months, and 1, 3, and 5 years were, respectively, 13.9 (+/- 5.3), 14.7 (+/- 5.6), 14.2 (+/- 5.4), 13.8 (+/- 3.7), and 12.6 (+/- 3.5). Seventeen percent (11 eyes) had a postoperative rise in IOP which needed medical or surgical intervention: 8 % (5 eyes) had a rise in IOP 1 day after DSEK, of which 1 underwent a trabeculectomy 7 months after DSEK surgery; 6 % (4 eyes) had a rise in IOP later in the postoperative period, which could all be managed medically; and 3 % (2 eyes) had increased IOP 1 day after DSEK and later in the postoperative period, both eyes underwent a trabeculectomy 5 and 24 months, respectively, after DSEK surgery. An increase in IOP was encountered in 17 % of DSEK patients. Checking the IOP in the short and long postoperative period is necessar

Straylight Measurements in Two Different Apodized Diffractive Multifocal Intraocular Lenses

PURPOSE: To evaluate differences in straylight between eyes implanted with a hydrophilic multifocal IOL (Seelens MF; Hanita Lenses, Hanita, Israel) and a hydrophobic multifocal IOL (SN6AD1; Alcon Laboratories, Inc., Fort Worth, TX). METHODS: In a prospective cohort study, routinely obtained straylight measurements (C-Quant; Oculus Optikgerate, Wetzlar, Germany) 3 months after standard phacoemulsification for either cataract or refractive lens procedures were compared. Patients were implanted with either the SeeLens MF IOL or the SN6AD1 IOL. Postoperative straylight values, visual acuity, and refractive outcomes were compared. RESULTS: The SeeLens MF IOL was implanted in 84 eyes and the SN6AD1 IOL in 79 eyes. The difference in straylight was 0.08 (P = .01), with the SeeLens MF IOL having less straylight. Postoperative CDVA was logMAR -0.03 +/- 0.06 in the SeeLens MF group, and logMAR -0.02 +/- 0.08 in the SN6AD1 group. Mean postoperative refraction was + 0.01 +/- 0.43 and + 0.06 +/- 0.35 D, respectively. CONCLUSIONS: The Seelens MF IOL showed a straylight of log(s) 0.08 lower than the SN6AD1 IOL. In terms of spherical equivalent and visual acuity the lenses performed equally. More study will aid in understanding the causes and clinical impact of this differenc