Accuracy of toric intraocular lens power calculation depending on different keratometry values using a novel network based software platform.

Purpose: To compare different corneal keratometry readings (swept-source-OCT-assisted biometry and Scheimpflug imaging) with a novel software platform for calculation of toric intraocular lenses. Setting: Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany. Design: Retrospective, non-randomized, clinical trial. Methods: Twenty-three eyes undergoing toric intraocular lens implantation were included. Inclusion criteria were preoperative regular corneal astigmatism of at least 1.00 D, no previous refractive surgery, no ocular surface diseases and no maculopathies. Lens exchange was performed with CALLISTO eye (Zeiss). For each patient, the expected postoperative residual refraction was calculated depending on three different corneal parameters of two different devices: standard K-front (K) and total keratometry (TK) obtained by a swept-source-OCT-assisted biometry system (IOL Master 700, Zeiss) as well as total corneal refractive power (TCRP) obtained by a Scheimpflug device (Pentacam AXL, Oculus). Barrett's formula for toric intraocular lenses was used for all calculations within a novel software platform (EQ workplace, Zeiss FORUM®). Results were statistically compared with postoperative refraction calculated according to the Harris dioptric power matrix. Results: The standard K values (mean PE 0.02 D ± 0.45 D) and TK values (mean PE 0.09 D ± 0.43 D) of the IOL Master 700 reached similar results (p = 0.96). 78% of eyes in both K and TK groups achieved SE within ±0.5 D of attempted correction and all eyes (100%) were within ±1.0 D of attempted correction in both groups. By contrast, the prediction error in the IOL calculation using the TCRP of the Scheimpflug device was significantly greater (mean PE -0.56 D ± 0.49 D; p = 0.00 vs. standard K and p = 0.00 vs. TK) with adjusted refractive indices. Thirty-nine and Ninety-one percentage of eyes in the TCRP group achieved SE within ±0.5 D (p = 0.008 K vs. TCRP and p = 0.005 TK vs. TCRP) and ± 1.0 D (p = 0.14 vs. TCRP) of attempted correction, respectively. Conclusion: All three corneal parameters (standard K, TK, TCRP) performed well in calculating toric IOLs. The most accurate refractive outcomes in toric IOL implantation were achieved by IOL calculations based on swept-source-OCT-assisted biometry. The SS-OCT-based K-front and TK values achieve comparable results in the calculation of toric IOLs.

Vitronectin stabilizes intravascular adhesion of neutrophils by coordinating ß2 integrin clustering.

The recruitment of neutrophils from the microvasculature to the site of injury or infection represents a key event in the inflammatory response. Vitronectin (VN) is a multifunctional macromolecule abundantly present in blood and extracellular matrix. The role of this glycoprotein in the extravasation process of circulating neutrophils remains elusive. Employing advanced in vivo/ex vivo imaging techniques in different mouse models as well as in vitro methods, we uncovered a previously unrecognized function of VN in the transition of dynamic to static intravascular interactions of neutrophils with microvascular endothelial cells. These distinct properties of VN require the heteromerization of this glycoprotein with plasminogen activator inhibitor-1 (PAI- 1) on the activated venular endothelium and subsequent interactions of this protein complex with the scavenger receptor low-density lipoprotein receptor-related protein-1 on intravascularly adhering neutrophils. This induces p38 mitogen-activated protein kinases-dependent intracellular signaling events which, in turn, regulates the proper clustering of the b2 integrin lymphocyte function associated antigen-1 on the surface of these immune cells. As a consequence of this molecular interplay, neutrophils become able to stabilize their adhesion to the microvascular endothelium and, subsequently, to extravasate to the perivascular tissue. Hence, endothelial-bound VN-PAI-1 heteromers stabilize intravascular adhesion of neutrophils by coordinating b2 integrin clustering on the surface of these immune cells, thereby effectively controlling neutrophil trafficking to inflamed tissue. Targeting this protein complex might be beneficial for the prevention and treatment of inflammatory pathologies.

Evaluation of total corneal power measurements with a new optical biometer.

PURPOSE: To evaluate the repeatability and validity of total corneal power measurements (total keratometry [TK]) obtained with a recently introduced optical biometer (IOLMaster 700, Carl Zeiss Meditec AG) to a Scheimpflug device (Pentacam, Oculus). SETTING: Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany. DESIGN: Prospective randomized controlled trial. METHODS: The inclusion criteria were a corneal astigmatism of 3.00 diopters (D) or less, no previous ocular surgery, no known corneal irregularities, and no known dry eyes. All eyes were measured 3 times using the optical biometer and the Scheimpflug device. The results were statistically compared using Bland-Altman, within-subject SD, and astigmatism vector analysis. RESULTS: Ninety-three eyes of 93 subjects were included. Overall, the repeatability of all eyes measured was 0.42 for standard K, 0.40 for TK, 0.45 for total corneal refractive power (TCRP), 0.43 for true net power (TNP), and 0.39 for simulated K. Bland-Altman analysis showed no significant difference between the optical biometer's TK compared with standard K and the Scheimpflug device's simulated K, TNP, and TCRP, the P value exceeding .05 in each case. A difference of >0.50 diopters between astigmatism measurements between TK and TCRP was found in 10 cases compared with standard K and TNP with 0 and 2 cases. CONCLUSIONS: Repeatability of both devices was high, although measurements of meridian showed a great variability, suggesting that numerous measurements are needed to enhance accuracy. TCRP measurements between recently introduced TK and TCRP cannot be used interchangeably. Future studies are necessary to evaluate which measurement will result in a better outcome when respective measurements are used for toric intraocular lens calculations.