Publications by authors named "Timur M Yildirim"

Background: Homogeneous intraocular lens (IOL) calcification deteriorates patient's visual quality. There is a lack of functional and patient-reported data on patients with this material change undergoing IOL exchange surgery. The aim of this study was to evaluate subjective and objective outcomes following IOL exchange due to homogeneous IOL calcification to improve evidence-based patient counseling.

View Article and Find Full Text PDF

Purpose: To assess visual outcomes and stability of lens alignment more than 3 years after implanting either the AT Lisa Tri Toric (Carl Zeiss Meditec) or the Acrysof IQ Restor Toric (Alcon Laboratories, Inc) intraocular lens (IOL).

Methods: Patients who had received either the AT Lisa Tri Toric or the Acrysof IQ Restor Toric IOL were included in the study. The average follow-up period was 5.

View Article and Find Full Text PDF
Article Synopsis
  • The study aimed to explore how calcium and phosphorus levels influence optical deterioration in intraocular lenses (IOLs) that have calcified.
  • Researchers analyzed 18 explanted IOLs, identifying differences between primary and secondary calcification by measuring straylight and light loss.
  • Findings revealed primary calcified IOLs had significantly higher calcium and phosphorus content, leading to greater optical impairment compared to secondary calcification, highlighting the importance of these minerals in visual quality deterioration.
View Article and Find Full Text PDF
Article Synopsis
  • The study investigates the relationship between phosphate levels in aqueous humor and the risk of calcification in intraocular lenses (IOLs), especially in diabetic patients.
  • In vitro tests involved different IOL models exposed to varying phosphate concentrations to assess calcification using several analytical methods.
  • Results indicated that higher phosphate concentrations and longer exposure times significantly increased the risk of IOL calcification, supporting the hypothesis that diabetic conditions may elevate this risk.
View Article and Find Full Text PDF

Purpose: In Descemet Membrane Endothelial Keratoplasty (DMEK) a gas bubble is usually used to attach the graft to the host cornea. In this study, we observed the bubble size and bubble-graft coverage at different gaze angles following DMEK.

Methods: This observational prospective study analyzed 465 images of patients who underwent an uneventful DMEK.

View Article and Find Full Text PDF
Article Synopsis
  • The study analyzed data from over 2500 intraocular lens (IOL) explantations to determine the causes and characteristics of explantation within the first year after implantation.
  • The study found that 1.9% of IOLs were explanted early, mainly due to dislocation, visual intolerance, opacification, and intraoperative complications, with the fastest explantations occurring due to intraoperative issues.
  • The findings suggest that there are areas for improvement in IOL design and implantation techniques, especially concerning intraoperative damages and early calcification of hydrophilic IOLs.
View Article and Find Full Text PDF

Background: In recent years intraocular lenses (IOLs) for correcting presbyopia have been significantly improved and diversified. There are currently many different IOL models based on a wide variety of optical designs.

Objective: The wide variety of available IOL solutions to correct presbyopia can be challenging for surgeons and patients.

View Article and Find Full Text PDF

Introduction: The aim of this study was to analyze posterior surface opacification in explanted silicone intraocular lenses (IOLs) with clinicopathologic correlation to asteroid hyalosis.

Methods: In a laboratory setup, 12 explanted silicone IOLs underwent laboratory analyses, including light microscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy for elemental composition (EDX). Relevant clinical data were obtained for each case, including gender, age at IOL implantation, dates of implantation and explantation, as well as history of neodymium-dopped yttrium aluminum garnet (Nd:YAG) laser treatments or other opacification removal attempts.

View Article and Find Full Text PDF

Cataract is among the leading causes of visual impairment worldwide. Innovations in treatment have drastically improved patient outcomes, but to be properly implemented, it is necessary to have the right diagnostic tools. This review explores the cataract grading systems developed by researchers in recent decades and provides insight into both merits and limitations.

View Article and Find Full Text PDF

Background: Chromatic aberration of the eye results from the dispersion of polychromatic light at the interfaces of ocular media. An intraocular lens (IOL) based approach utilizing the diffractive-multifocal principle has been proposed for its correction, but the clinical evidence on the impact of reducing or increasing chromatic aberration on the visual quality of pseudophakic patients remains scarce.

Methods: In this cross-sectional study, longitudinal chromatic aberration (LCA) effects were studied monocularly in 37 patients implanted with a monofocal lens.

View Article and Find Full Text PDF

Purpose: In intraocular lens (IOL) implantation, insertion of the IOL injector enlarges the clear corneal incision. A larger incision size (IS) is associated with a higher risk for surgically induced astigmatism and endophthalmitis. The goal of this study was to determine which parameters most influence the final IS.

View Article and Find Full Text PDF

Purpose: We evaluated implantation behavior and injector damage of two different IOL injector systems, the Multisert and the AutonoMe.

Design: Prospective, randomized, comparative study with laboratory investigation.

Methods: We examined used injectors from 48 bilateral cataract cases and assessed video recordings of each Implantation.

View Article and Find Full Text PDF

Differentiating between various intraocular lens (IOL) changes can be a challenge. In particular, certain IOL models carry the risk of late postoperative calcification. A major cause of IOL exchange surgery could be avoided if appropriate modifications were made during the IOL manufacturing process.

View Article and Find Full Text PDF

Background: Keratoconus is a bilateral, yet asymmetric disease. In rare cases, the second eye may show no signs of tomographic changes. The purpose of this study was to analyze the biomechanical characteristics in tomographically regular keratoconus fellow eyes.

View Article and Find Full Text PDF

Simultaneous implantation of a monofocal or monofocal toric intraocular lens (IOL) into the capsular bag and a multifocal IOL into the ciliary sulcus, referred to as duet procedure, allows us to create multifocality that is more easily reversible than the implantation of a capsular bag-fixated multifocal IOL. The optical quality and results after the duet procedure are equivalent to those of a capsular bag-fixated multifocal IOL. Patients who cannot tolerate the side effects of multifocal optics or who develop an ocular condition leading to loss of function such as age-related macular degeneration (AMD) or glaucoma in the course of their lives may benefit from the reversibility of the procedure.

View Article and Find Full Text PDF

Purpose: The smaller incision, new-generation implantable miniature telescope is a novel implant to optimize vision in retinal patients with central vision loss. Using Miyake-Apple techniques we visualized the device implantation, repositioning, and explantation, while noting capsular bag dynamics.

Methods: Using the Miyake-Apple technique, we assessed capsular bag deformation after successful implantation of the device in human autopsy eyes.

View Article and Find Full Text PDF

Aim: To determine the clinical risk factors that may increase the occurrence of intraocular lens (IOL) calcification in patients who had undergone pars plana vitrectomy (PPV).

Methods: The medical records of 14 patients who underwent IOL explantation due to clinically significant IOL opacification after PPV were reviewed. The date of primary cataract surgery, technique and implanted IOL characteristics; the time, cause and technique of PPV; tamponade used; additional surgeries; the time of IOL calcification and explantation; and IOL explantation technique were investigated.

View Article and Find Full Text PDF
Article Synopsis
  • Opacification from calcification in hydrophilic acrylic intraocular lenses is a significant complication after cataract surgery, leading to the need to remove the lens.* -
  • The study aimed to assess whether hydrophobic surface properties of some hydrophilic acrylic lenses could reduce the risk of calcification compared to standard hydrophilic and hydrophobic lenses.* -
  • Results showed that all hydrophilic lenses, regardless of their surface properties, experienced calcification, while the hydrophobic lenses did not, indicating that hydrophobic surfaces do not prevent crystal formation.*
View Article and Find Full Text PDF

In this meta-analysis and systematic literature review of refractive outcomes after Descemet membrane endothelial keratoplasty (DMEK), the extent of the refractive shift and an overview of reasons for refractive shift after DMEK are provided. The PubMed library was screened for articles containing the terms "Descemet membrane endothelial keratoplasty," "DMEK," "Descemet membrane endothelial keratoplasty combined with cataract surgery," "triple-DMEK" combined with "refractive outcomes," "refractive shift," and "hyperopic shift." The refractive outcomes after DMEK were analyzed and compared using a fixed and random effects model.

View Article and Find Full Text PDF

To evaluate the long-term posterior capsule opacification (PCO) formation, and glistening rate of the HOYA Vivinex (XY1) IOL compared to Alcon AcrySof (SN60WF). In this prospective, multicentric, randomized, paired-eye, open-label study, we included 87 subjects that underwent cataract surgery with IOL implantation, with 67 patients completing the 3-year follow-up. The completer population consisted of 32 subjects implanted with XY1 and 35 implanted with SN60WF.

View Article and Find Full Text PDF

The purpose of this study is to quantitatively assess lens opacity, using a swept-source optical coherence tomography (SS-OCT) device for anterior segment assessment, and establish the correlation with Scheimpflug imaging, corrected distance visual acuity (CDVA) and cumulative dissipated energy (CDE). This prospective cross-sectional single-center study enrolled 51 patients (51 eyes) with crystalline lens opacity. Patients with previous ocular surgery, pathologies or general disorders affecting vision were excluded.

View Article and Find Full Text PDF

Ophthalmic viscosurgical device (OVD) is used during intraocular surgery to protect ocular tissue. It requires complete removal from the eye by the end of surgery to avoid postoperative complications. This study compares the interaction of a cohesive OVD with two different intraocular lenses (IOLs) of different equilibrium water content.

View Article and Find Full Text PDF

Opacification through calcification of hydrophilic acrylic intraocular lenses (IOL) is a severe complication after cataract surgery. Causing symptoms that range from glare through to severe vision loss, the only effective therapy is explantation of the opacified IOL so far. Although IOL calcification is a well-described phenomenon, its pathogenesis is not fully understood yet.

View Article and Find Full Text PDF