Martin Baumeister

Comparison of manual and automated methods to determine horizontal corneal diameter

Purpose: To compare 2 manual methods and 2 automated devices for measuring the horizontal corneal diameter (white‐to‐white [WTW] distance). Setting: Department of Ophthalmology, Johann Wolfgang Goethe‐University, Frankfurt am Main, Germany. Methods: In 100 eyes of 61 patients, the WTW distance was measured independently by 2 examiners using the following techniques: the Holladay‐Godwin gauge, a measuring caliper, Zeiss IOLMaster, and Orbscan® II topography system (Bausch & Lomb). The results were compared with measurements on magnified slitlamp photographs of the anterior eye segment. Statistical evaluation was performed using the Bland‐Altman method for comparison of measurement techniques. Results: The mean horizontal corneal diameter was 11.91 mm ± 0.71 (SD) with the measuring caliper, 11.8 ± 0.60 mm with the Holladay‐Godwin gauge, 11.78 ± 0.43 mm with the Orbscan II, and 12.02 ± 0.38 mm with the IOLMaster. The coefficient of inter‐rater repeatability was 1.30 for the caliper, 0.92 for the Holladay‐Godwin gauge, 0.76 for the Orbscan II, 0.50 for the IOLMaster, and 1.16 for the manual measurement in anterior segment images. The results obtained with the caliper were statistically significantly different between the 2 examiners (P<.001). The measurements of examiner 2 using the caliper were significantly different from the measurements of the same examiner using the Holladay‐Godwin gauge. This was not the case with the 2 automated devices. Conclusions: Automated measurement of the WTW distance provides more precise results than measurements using manual methods. The Zeiss IOLMaster had the highest reliability in measuring corneal diameter.

Scotopic measurement of normal pupils: Colvard versus Video Vision Analyzer infrared pupillometer.

Purpose: To prospectively measure the scotopic pupil diameter in a normal population and to compare 2 infrared pupillometers for these measurements. Setting: Johann Wolfgang Goethe‐University, Department of Ophthalmology, Frankfurt am Main, Germany. Methods: The Colvard infrared pupillometer was compared to the Video Vision Analyzer (VIVA) infrared pupillometer under scotopic light conditions in 33 participants (aged 19 to 55 years). Reliability was assessed by 2 independent examiners (E1, E2). Statistical analysis was performed using a comparison method by Bland and Altman. Results: Mean pupil diameter was 6.16 mm ± 1.20 (SD) (range 3.20 to 9.00 mm) with all measurements taken under scotopic illumination. The mean scotopic pupil diameter was 6.08 ± 1.16 mm (range 3.2 to 8.4 mm) with the Colvard pupillometer and 6.24 ± 1.28 mm (3.5 to 9.0 mm) with the VIVA pupillometer. The mean differences between the Colvard and VIVA were −0.27 mm (E1) and −0.05 mm (E2). Limits of agreement ranged from 1.4 (Colvard) to 2.4 (VIVA). The coefficients of repeatability ranged from 0.7 (Colvard) to 1.1 (VIVA). Conclusions: A mean scotopic pupil diameter of 6.15 mm with a maximal pupil size of 9.00 mm can be expected in a normal population; this should be considered in refractive corneal and refractive lens surgery. Measurements with the Colvard pupillometer were more reliable and precise than those with the VIVA pupillometer.

Diffuse lamellar keratitis after laser in situ keratomileusis imaged by confocal microscopy.

OBJECTIVE To report the confocal microscopic findings of two different cases of diffuse lamellar keratitis (DLK) after primary laser in situ keratomileusis (LASIK) and LASIK flap relifting. DESIGN Observational case report of two cases. METHODS Two cases of DLK with different clinical appearances after primary LASIK and LASIK flap relift were selected. A third case of uneventful LASIK was selected as control case. Examination with a white-light tandem slit-scanning confocal microscope was performed in addition to routinely applied slit-lamp biomicroscopy. RESULTS In both cases, confocal microscopic examination showed infiltration of cells considered most likely to be mononuclear cells and granulocytes into the flap interface. Under treatment with topical steroids, the inflammation was reduced in both cases, to a minimum within 1 week, without loss of visual acuity. At this stage, only remnants of the granulocytelike cells, but not active inflammation, were imaged by confocal microscopic examination. CONCLUSIONS Our findings confirm the clinical observation that DLK is an inflammation confined to the flap interface. Confocal in vivo microscopy could be a useful noninvasive tool to study the course of DLK in humans.

Scanning electron microscopic characteristics of Phakic intraocular lenses

OBJECTIVE To analyze the surface quality of new generation phakic intraocular lenses (IOLs). DESIGN Experimental materials study. MATERIALS Three different new generation phakic IOLs: angle-fixated anterior chamber lens Chiron Vision NuVita MA20 (polymethylmethacrylate [PMMAD, iris-fixated anterior chamber lens Ophtec Artisan Iris-Claw (PMMA), posterior chamber lens Staar ICM (polymer from porcine collagen and 2-hydroxyethyl methacrylate [HEMA]). METHODS Representative samples of three different phakic IOLs underwent surface and edge-finish examination with light microscopy (LM). The phakic IOLs were then examined by use of scanning electron microscopy (SEM), and particular attention was given to optic surface quality, edge finish, haptic, and optic/haptic junction. RESULTS In all IOLs the LM examination showed a smooth and homogeneous surface. No irregularities, particularly at the optic front and back surface, optic edge, haptic, and the optic/haptic junctions, were detected by SEM. One exception was a minor surface roughness at the claws of an Artisan iris-fixated anterior chamber IOL. CONCLUSIONS Phakic IOLs are implanted either in the anterior or posterior chamber of healthy eyes, and high standards for their surface quality are required. The evaluation of surface properties with LM and SEM did not reveal any defects that contraindicate the implantation of phakic IOLs.

Confocal microscopic characteristics of stage 1 to 4 diffuse lamellar keratitis after laser in situ keratomileusis

Purpose: To evaluate 4 stages of diffuse lamellar keratitis (DLK) after laser in situ keratomileusis using confocal microscopy. Setting: Department of Ophthalmology, Johann Wolfgang Goethe‐University, Frankfurt am Main, Germany. Methods: This retrospective study comprised 17 eyes (15 patients): 11 cases of stage 1 DLK, 5 cases of stage 2, 1 case of stage 3, and 2 cases of stage 4. All eyes were examined by slitlamp biomicroscopy and confocal microscopy. Results: In all cases of stage 1 and 2 DLK, confocal microscopy showed infiltration of inflammatory cells into the flap stroma and the interface. The density of the infiltrates and the number of cells varied within the stage 1 corneas; all stage 2 corneas had dense infiltrates. In the eye with stage 3 DLK, an aggregation of presumed cell remnants was noticed. In the stage 4 cases, there was no active inflammation but stromal folds and numerous activated keratocytes were detected. Conclusions: Confocal microscopy showed differences in the appearances of the DLK groups. There were similarities in the features of stages 1 and 2. Only stages 1 and 2 represented active inflammation, whereas stages 3 and 4 showed the result of accumulation and decay of the inflammatory cells.

LASIK mit superiorem Hinge und Scanning-Spot-Excimerlaserablation zur Korrektur von Myopie und myopem Astigmatismus: Einjahresergebnisse einer prospektiven klinischen Studie an 100 Augen

ZusammenfassungHintergrund. In den letzten Jahren wird die Laser-in-situ-Keratomileusis (LASIK) vermehrt zur Korrektur von Fehlsichtigkeiten eingesetzt. Ziel der vorliegenden Auswertung war es, Sicherheit, Wirksamkeit, Vorhersagbarkeit, Stabilität sowie die Komplikationen der LASIK mit Scanning-Spot-Excimer-Technologie zu bewerten. Patienten und Methode. Hundert konsekutive LASIK-Operationen im Zeitraum zwischen 2/1998 und 2/1999 [60 Patienten im mittleren Alter von 37 Jahren (Spannbreite: 20–55 Jahre)] wurden ausgewertet. Als Schnittgerät für die Keratomileusis wurde das Hansatome™ Mikrokeratom mit superiorem Hinge eingesetzt (Flapdurchmesser: 9,5 mm), die Laserablation wurde mit einem Scanning-Spot-Excimerlaser (Technolas-C-Lasik-217) durchgeführt. Das sphärische Äquivalent der subjektiven manifesten Refraktion lag im Mittel bei −6,96±2,87 dpt, die mittlere Sphäre bei −6,47±2,71 dpt, der mittlere Astigmatismus bei −0,98±0,94 dpt. Vor der Behandlung erreichten 6% der Augen mit bester Korrektur nur einen Visus von 0,5. Kontrolluntersuchungen fanden präoperativ, nach 1 und 7 Tagen sowie nach 1, 4 und 12 Monaten statt. Sicherheit, Wirksamkeit, Vorhersagbarkeit, Stabilität der refraktiven Werte sowie die Komplikationen wurden mit der Datagraph-Software (Version 1.11) ausgewertet. Ergebnisse. Am ersten postoperativen Tag und nach einer Woche konnten alle 100 Augen nachuntersucht werden, nach einem Monat 96, nach vier Monaten 95 und nach einem Jahr 92 Augen. Nach einem Jahr verlor kein Auge zwei oder mehr Zeilen an Sehvermögen, 99% lagen im Bereich von ±1 Zeile und 1% gewann 2 Zeilen (Sicherheitsindex: 1,03). Es erreichten 92% aller Augen einen unkorrigierten Visus von ≥0,5, 77% ≥0,8 und 51% von ≥1,0 (Wirksamkeitsindex: 0,89); 60 Augen (65,21%) lagen im Bereich von ±0,5 dpt, 82 Augen (89,13%) im Bereich von ±1,0 dpt und 91 Augen (98,91%) im Bereich von ±2,0 dpt. Das mittlere sphärische Äquivalent betrug nach einem Jahr −0,15±1,31 dpt. Zwischen 1 und 12 Monaten zeigte sich eine mittlere Regression von −0,14 dpt. Auf Wunsch der Patienten wurden 5 Augen während der Studienperiode wegen Unter- oder Überkorrektur nachbehandelt. Schnittkomplikationen traten nicht auf. Hornhautinfektionen wurden nicht verzeichnet, eine diffuse lamelläre Keratitis (DLK) wurde 12-mal beobachtet, aber alle Fälle heilten komplikationslos ab. Bei 7 Augen kam es zu einer leichten Dezentrierung (<1 mm) der Ablation, die in einem Fall zu einer erhöhten Blendempfindlichkeit führte. Schlussfolgerung. Die LASIK-Operation mit superiorem Hinge und Scanning-Spot-Excimer-Photoablation ist zur refraktiven Behandlung von Myopie (bis maximal −12 dpt) und myopischem Astigmatismus (bis maximal −5 dpt cyl.) geeignet. Die refraktiven Ergebnisse zeigten über den Verlauf des 12-monatigen Untersuchungszeitraums hohe Stabilität. Die Vorhersagbarkeit der refraktiven Ergebnisse lässt sich weiter verbessern.AbstractPurpose. Recently laser-in-situ-keratomileusis (LASIK) has been increasingly used to correct refractive errors. The purpose of this investigation was to evaluate the safety, efficacy, predictability, stability and complications using the scanning spot excimer LASIK technology. Patients and methods. The results of 100 consecutive LASIK operations carried out between 2/1998 and 2/1999 on 60 patients (mean age 37 years, range 20–55 years) have been evaluated. The Hansatome™ microkeratome with a superior hinge (flap diameter: 9.5 mm) and a scanning spot excimer laser (Technolas C-Lasik 217) were used in all cases. The mean spherical equivalent of the subjective manifest refraction was −6.96±2.87 diopters (D), the mean sphere was −6.47±2.71 D and the mean astigmatism was −0.98±0.94 D. In 6% of the eyes preoperative visual acuity was not better than 20/40. Examinations were performed preoperatively, after 1 and 7 days, after 1, 4 and 12 months. Safety, efficacy, predictability, stability and complications were calculated using the datagraph software (version 1.11). Results. All 100 eyes were examined after 1 day and 1 week, 96 after 1 month, 95 after 4 months and 92 after 1 year. Following 1 year none of the eyes lost 2 or more lines of best corrected visual acuity, 99% were within ±1 line and 1% gained 2 lines (safety index 1.03). In 92% of all eyes an uncorrected visual acuity of ≥0.5 was reached, in 77% ≥0.8 and in 51% ≥1.0 (efficacy index 0.89). For 60 eyes (65.21%) a refractive correction of±0.5 D was necessary, for 82 eyes (89.13%) ±1.0 D and for 91 eyes (98.91%) ±2.0 D. The mean spherical equivalent after 1 year was −0.15±1.31 D. Between 1 and 12 months a mean regression of −0.14 D occurred. On the request of the patients, 5 eyes were retreated during the study period for under- or overcorrection. Complications due to the microkeratome did not occur. Corneal infections were not observed, a diffuse lamellar keratitis (DLK) was seen in 12 cases, but all cases healed with no loss of visual acuity. In 7 eyes a slight decentration of the ablation was observed using corneal topography, which in one case caused an increase in glare sensitivity. Conclusions. LASIK with superior hinge and scanning spot excimer photoablation is suitable for the correction of myopia (up to a maximum of −12 D) and for myopic astigmatism (up to a maximum of −5 D). The refractive results showed a high stability during the 12-month study period but there is still room for improvement of the predictability.

Cataract Surgery With Implantation of an Artificial Lens

BACKGROUND Cataract surgery, the most frequently performed operative procedure worldwide, typically concludes with the implantation of an artificial intraocular lens (IOL) to correct aphakia (absence of the crystalline lens). METHOD Selective literature review including current regulations, guidelines and recommendations for cataract surgery. RESULTS The main symptom of cataract is loss of visual acuity, which usually progresses slowly. It can arise in one eye or both. There is a basic distinction between congenital and acquired cataracts. The probability of developing a cataract rises with age because of biochemical aging processes. The development of a cataract becomes highly likely from the sixth decade of life onward. CONCLUSIONS As no effective medications for cataract are available at present, its current standard treatment is the removal of the clouded lens. In industrialized countries, this is usually done with ultrasound (phacoemulsification), followed by the implantation of an IOL.

Repeatability of lens densitometry using Scheimpflug imaging.

Purpose To evaluate the repeatability of different lens densitometry analysis modes performed with Scheimpflug imaging using the Pentacam HR device. Setting University eye hospital, Frankfurt am Main, Germany. Design Cross‐sectional study. Methods Eyes were analyzed under mydriasis during 2 examinations performed by the same examiner. Three single measurements were taken to assess lens densitometry via 3 modes as follows: peak (maximum), linear (vertical axis), and 3‐dimensional (3‐D). Measurements were also taken using 3 cylindrical reference blocks (P) with different diameters (2.0 mm, 4.0 mm, 6.00 mm) composing the whole lens depth. Repeatability was tested using Bland‐Altman analysis. As statistical parameters, the coefficient of repeatability (CoR) and the relative repeatability (RR) were applied. Results The study analyzed 105 eyes. The CoR of the peak modus was 5.6 (RR, 29.8%); of the linear modus, 0.9 (RR, 8.8%); and of the 3‐D modus, 0.36 (RR, 3.6%). The values of the P mode were lower, with a CoR between 0.19 and 0.30 (RR, 2.1%‐3.3%). Conclusions Lens densitometry using Scheimpflug imaging was highly repeatable. However, repeatability was dependent on the analysis mode used. Repeatability decreased with increasing opacification. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Intraokularlinsen zur Korrektur von Refraktionsfehlern

ZusammenfassungIm vorliegenden Übersichtsartikel wird der derzeitige Stand der Intraokularlinsenchirurgie zur Korrektur von Refraktionsfehlern dargestellt. Man unterscheidet zwischen additiver Chirurgie mit Kunstlinsenimplantation ohne Extraktion der kristallinen Linse [phake Intraokularlinse (PIOL)] und der Entfernung der natürlichen Linse mit Implantation einer Kunstlinse [refraktiver Linsenaustausch (RLA)]. Die phaken Intraokularlinsen (IOL) werden in kammerwinkelgestützte und irisgetragene Vorderkammerlinsen sowie sulkusfixierte Hinterkammerlinsen unterteilt. Die Implantation der phaken IOL (PIOL) hat sich als effektives, sicheres, vorhersagbares und stabiles Verfahren zur Korrektur von höheren Ametropien herausgestellt. Komplikationen sind selten und zwischen den 3 verschiedenen PIOL-Typen unterschiedlich, bei den Vorderkammerlinsen handelt es sich hauptsächlich um Pupillenverziehung und Endothelzellverlust.AbstractIn this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss.

[Intraocular lenses for the correction of refraction errors. Part 1: phakic anterior chamber lenses].

ZusammenfassungIm vorliegenden Übersichtsartikel wird der derzeitige Stand der Intraokularlinsenchirurgie zur Korrektur von Refraktionsfehlern dargestellt. Man unterscheidet zwischen additiver Chirurgie mit Kunstlinsenimplantation ohne Extraktion der kristallinen Linse [phake Intraokularlinse (PIOL)] und der Entfernung der natürlichen Linse mit Implantation einer Kunstlinse [refraktiver Linsenaustausch (RLA)]. Die phaken Intraokularlinsen (IOL) werden in kammerwinkelgestützte und irisgetragene Vorderkammerlinsen sowie sulkusfixierte Hinterkammerlinsen unterteilt. Die Implantation der phaken IOL (PIOL) hat sich als effektives, sicheres, vorhersagbares und stabiles Verfahren zur Korrektur von höheren Ametropien herausgestellt. Komplikationen sind selten und zwischen den 3 verschiedenen PIOL-Typen unterschiedlich, bei den Vorderkammerlinsen handelt es sich hauptsächlich um Pupillenverziehung und Endothelzellverlust.AbstractIn this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss.