Algorithm and software for field distortion correction in a commercial SD-OCT for corneal curvature assessment.

Accurate assessment of corneal curvatures using frequency domain optical coherence tomography (OCT) with galvanometer scanners remains challenging due to the well-known scan field distortion. This paper presents an algorithm and software for correcting the distortion using only two simple measurements in which a readily available standard sphere is positioned in different depths in front of the OCT scanner. This offers a highly accessible and easily reproducible method for the field distortion correction (FDC). The correction was validated by measuring different spherical phantoms and conducting corneal curvature measurements of ex vivo porcine corneas using a commercial spectral-domain OCT system and a clinically approved swept-source OCT as a reference instrument. Thus, the error in radius measurements of spherical phantoms was reduced by >90% and astigmatism by >80% using FDC. In explanted porcine eyes, the error in astigmatism measurements with the Telesto was reduced by 75% for power and 70% for angle. The best fitting sphere radius was determined up to a deviation of 0.4% from the Anterion. This paper describes a correction algorithm for OCT immanent distortion that is applicable to any scanning OCT setup and enables precise corneal curvature measurements. The MATLAB software for the FDC is publicly available on GitHub.

Long-Term Results of 0.19mg Fluocinolone Acetonide Insert for Treatment of Non-Infectious Uveitis in Clinical Practice.

PURPOSE: To evaluate the long-term outcomes of patients with non-infectious uveitis treated with 0.19 mg fluocinolone acetonide insert (FAi) for up to 36 months in clinical practice. METHODS: A retrospective study conducted at a single uveitis center. RESULTS: Fifty eyes of 39 patients were included. Mean best corrected visual acuity (BCVA) and central retinal thickness (CRT) remained stable until month 36 after FAi implantation (61.04 vs. 70.25 letters and 370.8 vs. 332.5 µm, respectively). The recurrence rate was 34% (17 eyes) after 36 months, of which 82% (14 eyes) received high-dose corticosteroids before FAi. Mean intraocular pressure (IOP) remained unchanged (13.38 vs. 15.74 mmHg), while most phakic eyes (13 of 14 eyes) required cataract surgery. CONCLUSIONS: We show that FAi effectively prevents recurrences of non-infectious uveitis for up to three years in clinical practice, comparable with randomized clinical trials. Patients who received high-dose corticosteroids before FAi have an increased risk for early recurrence and should be considered for scheduled re-treatment.

Rotational stability of plate haptic toric intraocular lenses after combined 25-gauge vitrectomy and cataract surgery.

AIM: To evaluate the postoperative intraocular lens (IOL) rotational stability and residual refractive astigmatism following combined 25-gauge vitrectomy and cataract surgery with implantation of a plate haptic toric IOL. METHODS: In this retrospective case series, 32 eyes of 32 patients underwent a combined 25-gauge vitrectomy and phacoemulsification for vitreoretinal diseases and cataract with regular corneal astigmatism of at least 1 diopter (D). A plate haptic toric IOL (AT Torbi 709M, Carl Zeiss Meditec AG) was implanted in all eyes. The outcome measures were rotational stability and refractive astigmatism up to 6mo postoperatively as well as the best corrected visual acuity (BCVA). RESULTS: Preoperative refractive astigmatism was 2.14±1.17 D, which was significantly reduced to 0.77±0.37 D six to eight weeks postoperatively and remained stable throughout the observation period (0.67±0.44 D at three months and 0.75±0.25 D at six months; for all groups: P<0.0001 compared to baseline). BCVA improved significantly from 0.36±0.33 logMAR preoperatively to 0.10±0.15 logMAR following surgery (P=0.02). Mean IOL axis deviation from the target axis was 3.4°±2.9° after six to eight weeks and significantly decreased over time (2.4°±2.6° six months after surgery; P=0.04). In one patient IOL, re-alignment was performed. CONCLUSION: Corneal astigmatism is significantly reduced following combined 25-gauge vitrectomy and cataract surgery. The plate haptic toric IOL position and axis remain stable during the observation period of six months.

Fluocinolone acetonide 0.19-mg implant for the treatment of noninfectious uveitis with involvement of the posterior segment: a real-world study.

PURPOSE: To evaluate the effectiveness of 0.19-mg fluocinolone acetonide implant (FAi) for preventing inflammatory relapses in noninfectious uveitis with posterior segment involvement in standard clinical practice. Further, to assess the value of remission induction therapy with intraocular and periorbital administered high-dose corticosteroids before FAi. METHODS: A retrospective cohort study in a tertiary referral center specialized in uveitis management. The primary study outcomes were the best-corrected visual acuity (BVCA) and central retinal thickness (CRT) within a 12-month observation period. The secondary outcomes were intraocular pressure (IOP) and intraocular inflammation. The main safety measures were IOP increase and cataract formation. RESULTS: In total, 76 eyes of 57 patients received FAi. Locally administered high-dose corticosteroids were applied in 68.4% of all eyes before FAi. BCVA remained stable within the 12-month observation period (63.21 vs. 62.95, difference 0.26 letters; 95% CI: - 6.31 to 6.84; p > 0.9). Significant CRT reduction upon FAi was sustained after 12 months (362.7 vs. 309.1 µm, difference 53.57 µm; 95% CI: 1.55 to 105.6; p = 0.04). Intraocular inflammation was reduced until 9 months of follow-up (0.82 vs. 0.3, difference 0.53; 95% CI: 0.11 to 0.95; p = 0.007). A mean IOP increase (13.68 vs. 15.6; difference - 1.92; 95% CI: - 3.85 to 0.004; p = 0.0507) and cataract development (20% of all phakic eyes) were noted. CONCLUSION: We observed similar levels of FAi effectiveness for the treatment of noninfectious uveitis in standard clinical practice compared to previous randomized clinical trials. Moreover, remission induction therapy before FAi can benefit patients with increased baseline uveitis activity.

Differential effects of Nintedanib and Pirfenidone on lung alveolar epithelial cell function in ex vivo murine and human lung tissue cultures of pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease. Repetitive injury and reprogramming of the lung epithelium are thought to be critical drivers of disease progression, contributing to fibroblast activation, extracellular matrix remodeling, and subsequently loss of lung architecture and function. To date, Pirfenidone and Nintedanib are the only approved drugs known to decelerate disease progression, however, if and how these drugs affect lung epithelial cell function, remains largely unexplored. METHODS: We treated murine and human 3D ex vivo lung tissue cultures (3D-LTCs; generated from precision cut lung slices (PCLS)) as well as primary murine alveolar epithelial type II (pmATII) cells with Pirfenidone or Nintedanib. Murine 3D-LTCs or pmATII cells were derived from the bleomycin model of fibrosis. Early fibrotic changes were induced in human 3D-LTCs by a mixture of profibrotic factors. Epithelial and mesenchymal cell function was determined by qPCR, Western blotting, Immunofluorescent staining, and ELISA. RESULTS: Low µM concentrations of Nintedanib (1 µM) and mM concentrations of Pirfenidone (2.5 mM) reduced fibrotic gene expression including Collagen 1a1 and Fibronectin in murine and human 3D-LTCs as well as pmATII cells. Notably, Nintedanib stabilized expression of distal lung epithelial cell markers, especially Surfactant Protein C in pmATII cells as well as in murine and human 3D-LTCs. CONCLUSIONS: Pirfenidone and Nintedanib exhibit distinct effects on murine and human epithelial cells, which might contribute to their anti-fibrotic action. Human 3D-LTCs represent a valuable tool to assess anti-fibrotic mechanisms of potential drugs for the treatment of IPF patients.