Gerald Schmidinger

Repeatability and Reproducibility of Central Corneal Thickness Measurement With Pentacam, Orbscan, and Ultrasound

Purpose. The authors conducted a comparison of anterior chamber depth (ACD) measurement by 3 devices of EchoScan, Orbscan II, and IOLMaster to assess the validity of the latter 2 and its reliability with Orbscan II. Methods. Forty-four myopic patients, 56.8% female, were enrolled in this prospective study. In all 88 eyes, the ACD was first measured with Orbscan II, followed by IOLMaster and EchoScan U3300, both under cycloplegia. The mean (± standard deviation) age and spherical equivalent were 30.2 ± 8.5 years and −4.98 ± 2.67 D, respectively. The difference between ACD measurements by these 3 devices was analyzed using the repeated-measures analysis of variance. Agreement between each pair of devices was assessed by computing the 95% limits of agreement (LoA). Orbscan II reliability was also evaluated by using the 95% LoA between 2 consecutive measurements. P value adjustments for multiple comparisons were performed using the Bonferroni method. Results. There was a statistically significant difference between measurements made with the 3 devices (p < 0.001). The mean difference between Orbscan II and Echoscan ACD measurements was −0.03 ± 0.12 mm, with the 95% LoA from −0.25 to +0.20 mm, and between IOLMaster and Echoscan measurements, it was +0.09 ± 0.14 mm with the 95% LoA from −0.18 to +0.36 mm. On average, Orbscan II readings were lower and those of IOLMaster were higher than Echoscan readings. Both Orbscan II and IOLMaster agreed with Echoscan in measuring ACD. The 2 readings by Orbscan II had a 95% LoA of −0.05 and +0.07 mm that shows good reliability. Conclusion. ACD measurement differences with the 3 studied devices proved to be statistically significant; however, these minor differences may be clinically negligible depending on the use of the measurement. As an advantage, both Orbscan II and IOLMaster are noncontact, and with their ACD measurements being valid, they may be considered suitable devices for this purpose. In addition, Orbscan II produces highly repeatable ACD measurements.

Validity and Repeatability of Anterior Chamber Depth Measurements With Pentacam and Orbscan

Purpose. The purpose of this study was to determine the validity and repeatability of anterior chamber depth (ACD) measurements obtained with a novel rotating Scheimpflug camera (Pentacam; Oculus Optikgeräte GmbH, Wetzlar, Germany) to scanning slit topography (Orbscan; Bausch & Lomb, Rochester, NY). Methods. ACD in 60 healthy eyes was measured twice by two independent observers with each modality in random order. A total of eight measurements was performed on each eye. The mean differences between measurements, between observers, and between modalities were calculated, and 95% limits of agreement (LoA) were given as mean ± 1.96 * standard deviation (SD) of the mean. Results. The mean ACD values as determined with the different modalities (± SD) were 3.18 ± 0.38 mm for Pentacam imaging and 3.23 ± 0.40 for Orbscan. The mean difference between the two modalities was 0.047 mm (LoA: 0.176 to -0.081 mm). Within each modality, the limits of agreement of the differences between individual measurements and between different observers were within 0.073 mm or 4% of total ACD. The total variance in the observed data was 0.145. The variance resulting from interindividual differences in ACD was 85%, as a result of the two different modalities 15%, as a result of different observers 0.007%, and as a result of different measurements 0.007%. Conclusions. In the assessment of normal eyes, the differences of ACD values measured with Orbscan and Pentacam were within clinically acceptable levels, and inter- and intraobserver variability was considerably below clinically significant levels. Thus, these two modalities can be regarded as interchangeable.

Angiogenic and inflammatory markers in the intraocular fluid of eyes with diabetic macular edema and influence of therapy with bevacizumab.

Purpose: The purpose of this study was to determine the concentrations of angiogenic and inflammatory markers in human eyes with diffuse diabetic macular edema before and during therapy with intravitreal bevacizumab and their association with disease activity. Methods: In a prospective clinical trial, 10 eyes of 10 consecutive patients with vision loss because of diabetic macular edema were compared with 10 eyes of 10 age-matched controls. Bevacizumab was administered at baseline; retreatments were given monthly according to disease activity. During a follow-up of 6 months, aqueous humor samples were taken each time intravitreal therapy was administered. A multiplex assay was used for measurement of 12 different growth factors and cytokines. Results: Aqueous humor of eyes with diabetic macular edema demonstrated a significantly increased expression of monocyte chemoattractant protein-1 and interleukin-8 and higher, but not significant, levels of interleukin-6 and vascular endothelial growth factor. Intravitreal therapy with bevacizumab resulted in a significant decrease of vascular endothelial growth factor below physiologic levels. This change was not associated with clinical disease activity as measured by visual acuity and central retinal thickness. Conclusion: Eyes with diabetic macular edema showed a different profile of monocyte chemoattractant protein-1 and interleukin-8 as compared with controls. The intraocular vascular endothelial growth factor expression decreased significantly after the first intravitreal injection of bevacizumab; this reduction was prolonged by consecutive monthly retreatment.

Long-term Changes in Posterior Chamber Phakic Intraocular Collamer Lens Vaulting in Myopic Patients

OBJECTIVE Evaluation of central and midperipheral vaulting of the posterior chamber phakic intraocular Collamer lens (ICL; Staar Surgical Inc., Monrovia, CA) in eyes with moderate to high myopia. DESIGN Retrospective analysis of prospectively collected data. PARTICIPANTS Eighty-four eyes treated with the latest ICL (V4 model) and 27 eyes treated with early ICL models were examined. METHODS After standardized ICL implantation, patients underwent complete ophthalmologic examinations before surgery and at 1 week, 1 month, 3 months, 6 months, and at yearly intervals thereafter. Central vaulting was measured using the Jaeger device (Haag-Streit, Bern, Switzerland). From 2006 onward, vaulting was measured additionally by optical coherence tomography (Visante OCT; Carl Zeiss Meditec, Jena, Germany). Using the Visante OCT, the crystalline lens rise and the midperipheral vaulting of the ICL were assessed. MAIN OUTCOME MEASURES Central vaulting after ICL implantation. RESULTS The mean duration of follow-up was 74.1+/-23.1 months and 96.3+/-50.2 months in eyes treated with V4 and early models, respectively. Postoperative central vaulting was 466+/-218 microm (range, 30-900 microm) in eyes treated with the V4 models and 321+/-200 microm (range, 150-900 microm) in those treated with early ICL models. From the 6-month follow-up onward, a continuous and nearly linear reduction of central vaulting was observed. At the 10-year follow-up, the mean central vaulting was reduced to 184+/-159 microm (range, 6-500 microm) and 138+/-218 microm (range, 0-820 microm) in eyes treated with V4 or early models, respectively. Eyes with total vaulting had a mean central vaulting of 407+/-202 microm (range, 180-730 microm), whereas those with midperipheral contact had a significantly lower central vaulting of 105+/-87 microm (range, 0-200 microm). CONCLUSIONS This study revealed consistent reduction of central vaulting over a 10-year period and provides further evidence that insufficient vaulting of the ICL is responsible for the development of anterior subcapsular cataract. A minimum central vaulting of 230 microm seems to be necessary to ensure total vaulting of the ICL. If an ICL is chosen for the correction of myopia, targeting for the greatest possible postoperative central vaulting is advised to achieve safe and complete vaulting for several years.

Influence of Blue-Light-Filtering Intraocular Lenses on Color Perception and Contrast Acuity

PURPOSE To compare contrast acuity at different illumination levels and color vision and the subjective impression in patients after bilateral cataract surgery with a mixed implantation of a blue-light-filtering and an ultraviolet (UV)-filtering intraocular lens (IOL). DESIGN Randomized, controlled, double-masked, and bilateral study with intraindividual comparison. PARTICIPANTS This study included 48 eyes of 24 consecutive patients with age-related cataract. METHODS Each patient had standardized small incision cataract surgery with IOL implantation into the capsular bag. Patients were randomly assigned to receive a blue-light-filtering Hoya AF-1 (UY) YA-60BB IOL in one eye and a UV-filtering Hoya AF-1 (UV) VA-60BB IOL (Hoya Medical Europe, Frankfurt/Main, Germany) in the contralateral eye. Contrast acuity was measured at illumination levels of 500, 5, and 0.5 lux and contrast levels of 100%, 50%, 25%, 12.5%, and 6.25%. Color vision was assessed using the Lanthony desaturated D-15 test, the Lanthony new color test (Munsell chroma 2 and 4), and an anomaloscope. Blue/yellow foveal threshold was tested applying short-wave automated perimetry. The subjective visual impression of patients was evaluated using a questionnaire. MAIN OUTCOME MEASURES Contrast acuity, color vision, and foveal threshold. RESULTS The blue-light-filtering IOLs had worse contrast acuity (P = 0.0004) and foveal threshold (P = 0.008) compared with the UV-filtering IOLs. Color vision tests and high-contrast visual acuity did not show any statistically significant differences between IOLs (P>0.05). On questioning, 3 of 24 patients noticed a difference between the implanted IOLs concerning visual impression. CONCLUSIONS This study shows that blue-light-filtering IOLs negatively affect contrast acuity and blue/yellow foveal threshold when compared with UV-filtering IOLs. Although the differences were small, the results suggest bilateral implantation of the same IOL type and avoidance of a mixed implantation of a blue-light-filtering IOL in one and a non-blue-light-filtering IOL in the contralateral eye in patients with high demands in color vision. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Contrast sensitivity function in eyes with diffractive bifocal intraocular lenses.

PURPOSE: To evaluate the image quality of asymmetric Acri.Twin bifocal intraocular lenses (IOLs) (Acri.Tec) by comparing distance and near black–white contrast sensitivity function with that of the Pharmacia 811E IOL. SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. METHODS: Thirty‐two eyes of 16 patients were examined after contralateral implantation of 1 Acri.Twin near‐weighted 733D IOL and 1 Acri.Twin distance‐weighted 737D IOL. Twenty eyes in 10 patients were examined after binocular Pharmacia 811E IOL implantation. Best corrected distance and near visual acuities were determined. Individual reading distance was recorded and corrected to 40 cm for the near contrast test (Holladay Contrast Acuity Test). Distance contrast sensitivity function was evaluated using the Acuity Max (Science 2020) computer program. RESULTS: Best corrected distance visual acuity was significantly better in patients with the 737D IOL than in those with the 733D or 811E IOLs. For distance reading with best distance correction, the 733D IOL performed better than the 737D and the 811E. Individual reading distance with the Acri.Twin IOL and 811E IOL was 33.6 cm and 34.0 cm, respectively. Best distance‐corrected near contrast sensitivity function was better in eyes with the near‐weighted 733D IOL. Binocular testing showed a significant difference between the 2 groups only at low‐contrast values. At distance, contrast sensitivity function was better with the 737D IOL, whereas no difference was found between the 733D and the 811E IOLs. Binocular contrast sensitivity function at distance revealed statistically significantly better results in the Acri.Twin group. CONCLUSION: An asymmetric diffractive bifocal lens system was advantageous in terms of vision quality when implanted binocularly and superior to monocular stronger weighted focus compared with conventional bifocal IOLs.

Depth of focus in eyes with diffractive bifocal and refractive multifocal intraocular lenses

PURPOSE: To evaluate monocular and binocular depth of focus in eyes with different multifocal intraocular lens (IOLs) systems. SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. METHODS: In this comparative interventional study, binocular implantation of multifocal IOLs was performed in 3 groups. In the first group, 26 eyes of 13 patients received asymmetric Acri.Twin (Acri.Tec) IOLs, a near‐weighted 733D in 1 eye and a distance‐weighted 737D in the fellow eye. In the second group, 26 eyes of 13 patients received a diffractive 811E IOL (Pharmacia). In the third group, 26 eyes of 13 patients received a refractive Array IOL (AMO). The visual acuity was tested monocularly and binocularly starting at 6 m in 0.50 diopter (D) defocusing steps. RESULTS: Distance visual acuity was best in eyes with the distance‐dominated 737D IOL; eyes with the other IOLs had comparable results. Binocular distance visual acuity was comparable between the Acri.Twin group and the 811E group. The Acri.Twin group had better distance visual acuity than the Array group (P≤.048). Near visual acuity was best in eyes with the near‐weighted 733D, followed by the 737D and the 811E. Patients with Array IOLs had worse visual acuities at reading distance (between 33 cm and 40 cm) (P≤.001). Patients with diffractive bifocal IOLs had better results than patients with refractive multifocal IOLs at reading distance (P≤.018). CONCLUSION: The diffractive IOLs performed better than refractive IOLs. Asymmetric‐weighted IOLs provided better binocular depth of field.

Repeated intravitreal bevacizumab (Avastin®) treatment of persistent new vessels in proliferative diabetic retinopathy after complete panretinal photocoagulation

Acta Ophthalmol. 2011: 89: 76–81

Localized opacification of hydrophilic acrylic intraocular lenses after procedures using intracameral injection of air or gas

Purpose To describe clinical and laboratory findings in a series of cases of intraocular lens (IOL) opacification after procedures involving intracameral injections of air or gas. Setting John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Design Experimental study. Methods Seven hydrophilic acrylic IOLs explanted after Descemet‐stripping endothelial keratoplasty (DSEK) or Descemet‐stripping automated endothelial keratoplasty (DSAEK) because of a localized central optic opacification associated with decrease in visual acuity and complaints of foggy vision were analyzed. The explanted IOLs were sent to our laboratory in the dry state or in fixative by the explanting surgeons. They underwent pathological and histochemical evaluation (alizarin red and von Kossa method). Light scattering measurements were also performed on the surface of 1 explant using Scheimpflug photography. A questionnaire was sent to the surgeons to obtain information pertinent to each case. Results The 7 explanted IOLs were represented by 6 hydrophilic acrylic designs from 5 manufacturers. Gross and light microscopy showed that granular deposits were densely distributed in an overall round pattern within the margins of the capsulorhexis or the pupil on the anterior surface/subsurface of the IOLs. The granules stained positive for calcium (alizarin red and von Kossa method). Light scattering on the anterior optic surface was very high (228 versus 13 computer‐compatible tapes on a control IOL). Conclusions A localized pattern of calcification was seen on the anterior surface/subsurface of various hydrophilic acrylic IOLs. Surgeons should be aware of this phenomenon following DSEK/DSAEK procedures in pseudophakic patients with hydrophilic acrylic IOLs. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Intraindividual comparison of color contrast sensitivity in patients with clear and blue-light-filtering intraocular lenses.

PURPOSE: To evaluate the effect of blue‐light‐filtering intraocular lenses (IOLs) with a yellow chromophore on color contrast sensitivity by intraindividual comparison with an identically designed IOL without a blue‐light filter. SETTING: Medical University of Vienna, Department of Ophthalmology, Vienna, Austria. METHODS: Randomized implantation of an AF‐1 (UV) IOL (Hoya) in 1 eye and an AF‐1 (UY) IOL (Hoya) in the contralateral eye was performed after phacoemulsification and primary posterior curvilinear capsulorhexis. Three months postoperatively, the best distance‐corrected visual acuity was evaluated. Before color contrast sensitivity testing, a heterochromatic flicker test was performed in both eyes to avoid error in brightness matching. Central and peripheral tritan color contrast sensitivities were evaluated using the Moorfields Vision System (CH Electronics). RESULTS: Visual acuity did not differ significantly between the 2 IOL groups (P>.05). The central color contrast sensitivity threshold also did not differ significantly between eyes with a clear IOL and eyes with a yellow IOL at any tested spatial frequency. The peripheral color contrast sensitivity test showed slightly higher color contrast sensitivity thresholds in eyes with a yellow IOL, although the differences were not statistically significant. Two patients independently reported subjective changes in color perception in the eye with the yellow IOL. CONCLUSION: In this intraindividual comparison, the implantation of a blue‐light‐filtering IOL did not lead to a clinically significant change in color contrast sensitivity.