ABSTRACT
OBJECTIVE: Aim of this study was to use a combination of partial least squares regression and a machine learning approach to predict IOL tilt using pre-operative biometry data. SETTING: Patients scheduled for cataract surgery at the Kepler University Clinic Linz. DESIGN: Prospective single center study. METHODS: Optical coherence tomography, autorefraction and subjective refraction was performed at baseline and 8 weeks after cataract surgery. In analysis I only one eye per patient was included and a tilt prediction model was generated. In analysis II a pair-wise comparison between right and left eyes was performed. RESULTS: In analysis I 50 eyes of 50 patients were analysed. Difference in amount, orientation and vector from pre- to post-operative lens tilt was -0.13°, 2.14° and 1.20° respectively. A high predictive power (variable importance for projection) for post-operative tilt prediction was found for pre-operative tilt (VIP=2.2), pupil decentration (VIP=1.5), lens thickness (VIP=1.1), axial eye length (VIP=0.9) and pre-operative lens decentration (VIP=0.8). These variables were applied to a machine learning algorithm resulting in an out of bag score of 0.92°. In analysis II 76 eyes of 38 patients were included. The difference of pre- to post-operative IOL tilt of right and left eyes of the same individuum was statistically relevant. CONCLUSION: Post-operative IOL tilt showed excellent predictability using pre-operative biometry data and a combination of partial least squares regression and a machine learning algorithm. Pre-operative lens tilt, pupil decentration, lens thickness, axial eye length and pre-operative lens decentration were found to be the most relevant parameters for this prediction model.
ABSTRACT
Purpose: The purpose of this study was to investigate the diagnostic value of anterior segment optical coherence tomography (AS-OCT) scans for Pseudomonas keratitis. Methods: Patients with treatment-naïve keratitis underwent AS-OCT imaging. The following parameters were evaluated: corneal thickness (CT), infiltrate thickness (IT), infiltrate diameter (ID), tissue loss/gain, entropy, and distance of the lesion from the corneal pupillary center. Three different OCT devices were used for the analysis. The relationship between the detected pathogen and the OCT patterns was analyzed. Results: Nineteen eyes of 19 patients were included in the analysis: seven cases in the Pseudomonas group and 12 cases in the Gram-positive group. The mean (SD) values for the Pseudomonas and Gram-positive groups, respectively, were as follows: CT, 834 µm (165 µm) and 760 µm (120 µm); IT, 290 µm (152 µm) and 287 µm (84 µm); ID, 2067 µm (1470 µm) and 1307 µm (745 µm); distance to center, 3.0 mm (1.2 mm) and 3.0 mm (1.6 mm); epithelial defect, 1193 µm (586 µm) and 484 µm (615 µm); tissue gain, +31% (19%) and +10% (12%); and entropy level, 4.0 (0.8) and 3.9 (1.1). Conclusions: This study introduces novel insights by identifying specific OCT parameters that distinguish Pseudomonas keratitis, including a 30% tissue gain. These findings align with earlier research that underscores the potential of OCT in differentiating various pathogens causing keratitis. Translational Relevance: The findings of this study could be used to develop new diagnostic strategies for Pseudomonas keratitis. The OCT findings could be used to develop new biomarkers for the infection.
Subject(s)
Keratitis , Tomography, Optical Coherence , Humans , Keratitis/diagnostic imaging , Cornea/diagnostic imaging , Pseudomonas , PupilABSTRACT
PURPOSE: To compare the lens tilt after apex-centered capsulotomy with standard pupil-centered capsulotomy. SETTING: Clinical practice. DESIGN: Prospective, randomized, investigator-masked trial. METHODS: This prospective, randomized, investigator masked study included 40 patients with age-related cataract scheduled for femtosecond laser-assisted cataract surgery (FLACS) in both eyes. The main outcome was the tilt of the intraocular lens (IOL), measured with the IOLMaster 700. RESULTS: The study enrolled 80 eyes of 40 patients. The mean distance from the center of the apex-centered capsulotomy to the pupil-centered capsulotomy was 175.8 ± 97.2 µm. The amount of IOL tilt was not significantly reduced with the new technique (P > .05). Tilt orientation was more stable in eyes treated with apex-centered capsulotomy. CONCLUSIONS: Centration of the capsulotomy on the lens apex in FLACS does not influence the amount of IOL tilt but the orientation stability. The clinical importance of this finding has to be further elucidated.
