Publications by authors named "Theofilos Tourtas"
Article Synopsis
- The study focuses on the histological findings and AS-OCT results in patients suffering from severe keratomalacia and corneal perforation due to vitamin A deficiency (VAD).
- Four patients were examined, with most showing severe VAD and evidence of corneal damage, including perforation in three cases.
- The findings highlight a correlation between AS-OCT imaging and histological results, demonstrating that keratomalacia, while rare, can still occur in well-nourished populations, showcasing symptoms such as Bitot's spots in one patient.
Purpose: To analyze the feasibility and outcome of Descemet membrane endothelial keratoplasty (DMEK) for treatment of endothelial failure in primary angle closure suspect (PACS) eyes.
Methods: Retrospective, single-center case series of eyes treated by DMEK for endothelial failure caused by PACS. Main study parameters were success rate of DMEK, best-corrected visual acuity, anterior chamber depth, central corneal thickness, and endothelial cell density.
Purpose: This study evaluated the dysregulation of TCF4 isoforms and differential exon usage (DEU) in corneal endothelial cells (CECs) of Fuchs endothelial corneal dystrophy (FECD) with or without trinucleotide repeat (TNR) expansion in the intron region of the TCF4 gene.
Methods: Three RNA-Seq datasets of CECs (our own and two other previously published datasets) derived from non-FECD control and FECD subjects were analyzed to identify TCF4 isoforms and DEU events dysregulated in FECD by comparing control subjects to those with FECD with TNR expansion and FECD without TNR expansion.
Results: Our RNA-Seq data demonstrated upregulation of three TCF4 isoforms and downregulation of two isoforms in FECD without TNR expansion compared to the controls.
Purpose: The purpose of this study was to investigate the differences in guttae ultramorphology and their relation to visual function in eyes with Fuchs endothelial corneal dystrophy (FECD).
Methods: Thirty FECD eyes without ocular comorbidities were included. Visual functional parameters (best-corrected visual acuity with high-contrast and low-contrast letters and contrast sensitivity/LogCS) and corneal morphology measured with Scheimpflug tomography (Pentacam) were assessed.
Fuchs endothelial corneal dystrophy (FECD) is the most common inherited corneal disease. Fibrillar focal excrescences called guttae and corneal edema due to corneal endothelial cell death result in progressive vision loss. Multiple genetic variants have been reported, but the pathogenesis of FECD is not fully understood.
View Article and Find Full Text PDFBackground/aims: Ectasia of the cornea can occur decades after penetrating keratoplasty (PK), especially in keratoconus eyes. The purpose of this study was to characterise ectasia after PK by morphological findings in anterior segment optical coherence tomography (AS-OCT).
Methods: In this retrospective, single-centre case series, 50 eyes of 32 patients with a history of PK at an average of 25±10 years earlier were included.
Purpose: The purpose of this study was to describe the feasibility of Descemet membrane endothelial keratoplasty (DMEK) as a treatment modality for spontaneous detachment of DM (DMD) decades after penetrating keratoplasty (PK) for keratoconus.
Methods: We describe the clinical characteristics and therapeutic surgical approach in 6 eyes of 5 patients with DMD. Clinical images, anterior segment optical coherence tomography scans, and histological findings are presented.
Purpose: This study aimed to evaluate the clinical outcomes up to 10 years after Descemet membrane endothelial keratoplasty (DMEK).
Methods: In this retrospective, consecutive, single-center case series the medical files of eyes which have received DMEK between 2009 and 2012 for the treatment of endothelial dysfunction was evaluated regarding follow-up time and clinical outcomes. Annual examinations of best-corrected visual acuity (BCVA), endothelial cell density (ECD), central corneal thickness (CCT) of 66 eyes which fulfilled the criterion of a minimum of 8 years follow-up were analyzed.
Purpose: Rho-associated kinase (ROCK) inhibitors have been successfully used as a rescue strategy in eyes that failed to clear after descemetorhexis without endothelial graft for treatment of Fuchs endothelial corneal dystrophy (FECD). The functional mechanisms by which ROCK inhibitors modulate corneal endothelial cell regeneration in FECD patients have, however, not been clarified. Here, we analyzed the effect of the ROCK inhibitor ripasudil on corneal endothelial cells of FECD patients and normal donors using ex vivo tissue and in vitro cellular models.
View Article and Find Full Text PDFPurpose: Descemet membrane endothelial keratoplasty is often combined with phacoemulsification and intraocular lens implantation (DMEK + cataract/IOL triple procedure) in phakic patients. This procedure results in a refractive shift that is difficult to predict. The aim of this study was to evaluate the hypothesis that the refractive shift in the second eye follows the shift in the first eye.
View Article and Find Full Text PDFIntroduction: Since the beginning of the COVID-19 pandemic there has been some debate regarding the risk of transmission through tissue transplantation and tissue banking processes.
Aim Of The Study: To analyze the changes that SARS-CoV-2 has caused regarding the harvesting of corneal donor tissue and eye bank activities in Germany.
Methods: A questionnaire was provided to 26 eye banks in Germany, consisting of questions about adaptations made in the screening of potential donors and the harvesting of corneal tissue following the pandemic spread of SARS-CoV-2.
Aims: To evaluate the contrast sensitivity in patients with nuclear cataract and corneal guttae compared to patients with nuclear cataract without guttae.
Methods: In this retrospective, single-centre case series, 50 eyes of 50 patients fulfilling the inclusion criteria were enrolled. Patients with corneal guttae and nuclear cataract (n=25, study group) underwent triple Descemet membrane endothelial keratoplasty (DMEK).
Purpose: To investigate single nucleotide polymorphisms (SNPs) and trinucleotide repeat (TNR) expansion in the transcription factor 4 (TCF4) gene in a large cohort of German patients with Fuchs endothelial corneal dystrophy (FECD).
Methods: Genomic DNA was obtained from 398 patients with FECD and from 58 non-FECD controls. Thirty-seven previously reported SNPs were evaluated by genotyping.
Purpose: CTG trinucleotide repeat (TNR) expansion is frequently found in transcription factor 4 (TCF4) in Fuchs' endothelial corneal dystrophy (FECD), though the effect of TNR expansion on FECD pathophysiology remains unclear. The purpose of this study was to evaluate the effect of TNR expansion on TCF4 expression in corneal endothelium of patients with FECD.
Methods: Peripheral blood DNA and Descemet membrane with corneal endothelium were obtained from 203 German patients with FECD.
Purpose: To compare the incidence of fungal infection after endothelial keratoplasty (EK) when donor tissue had been stored in hypothermic medium or organ culture.
Methods: We describe the clinical features of 10 cases of fungal infection (keratitis or endophthalmitis) following EK identified at three European centres. Case definition was the culture of fungus or a positive PCR from the host cornea or anterior chamber after EK.
Purpose: To evaluate the incidence, clinical course, and management of fungal interface keratitis (IK) after Descemet membrane endothelial keratoplasty (DMEK).
Methods: This is a single-center retrospective observational case series of 3950 eyes undergoing DMEK. Six eyes with fungal IK were detected and analyzed.
Purpose:: To analyze and correlate corneal parameters with refractive shift after Descemet membrane endothelial keratoplasty combined with cataract surgery (triple Descemet membrane endothelial keratoplasty).
Methods:: This single-center retrospective observational case series included 152 eyes of 152 consecutive patients undergoing triple Descemet membrane endothelial keratoplasty in the first eye for Fuchs endothelial corneal dystrophy. Patients were examined preoperatively, as well as at 3, 6, and 12 months after surgery.
Purpose: To perform a fellow eye comparison of outcomes and complications when using air or sulfur hexafluoride (SF6) gas as a tamponade in Descemet membrane endothelial keratoplasty (DMEK).
Methods: One hundred thirty-six eyes of 68 consecutive patients who underwent uneventful DMEK in both eyes for Fuchs endothelial corneal dystrophy were included in this retrospective study. Inclusion criteria were air tamponade (80% of the anterior chamber volume) in the first eye and 20% SF6 gas tamponade (80% of the anterior chamber volume) in the second eye; and same donor tissue culture condition in both eyes.
Purpose: To evaluate the impact of the air bubble on endothelial cell loss using the "bubble-in-the-roll" technique during Descemet membrane endothelial keratoplasty (DMEK).
Methods: Twenty DMEK grafts not suitable for transplantation were manually prepared from organ-cultured corneoscleral discs and injected into culture media using the Endoject DMEK injector (Medicel AG, Wolfhalden, Switzerland). Based on the injection method, the grafts were divided into 2 groups: In group A (n = 10), a small air bubble was placed inside the graft roll while it was in the injector.
Fuchs endothelial corneal dystrophy (FECD) is a slowly progressive bilateral disease of corneal endothelium in which accumulation of extracellular matrix (ECM) and loss of corneal endothelial cells (CECs) are phenotypic features. The corneal endothelium maintains corneal transparency by regulating water hydration; consequently, corneal endothelial dysfunction causes serious vision loss. The only therapy for corneal haziness due to corneal endothelial diseases, including FECD, is corneal transplantation using donor corneas, and no pharmaceutical treatment is available.
View Article and Find Full Text PDFPurpose: The unfolded protein response (UPR) is believed to play a role in the pathogenesis of Fuchs' endothelial corneal dystrophy (FECD). The purpose of this study was to investigate whether unfolded proteins accumulate in the corneal endothelium in FECD and if they are involved in triggering cell death.
Methods: Descemet's membranes with corneal endothelial cells (CECs) were obtained during keratoplasty, and expression of aggresomes, type 1 collagen, fibronectin, and agrin was evaluated.
Aim: To determine whether clinical performance is negatively affected by prestripping Descemet membrane endothelial keratoplasty (DMEK) grafts from organ-cultured corneas.
Methods: We reviewed clinical records of all patients who underwent DMEK surgery for Fuchs endothelial dystrophy between 28 October 2014 and 11 August 2015. Grafts had been prepared from organ-cultured corneoscleral buttons 24 hours prior to surgery or during surgery.
Purpose: To analyze the role of initial intraoperative intraocular pressure (IOP) in graft adhesion in Descemet membrane endothelial keratoplasty (DMEK) during early follow-up.
Methods: This retrospective, observational, single-center case series included 118 eyes from 118 consecutive patients treated between May and July 2015 for DMEK or combined DMEK and phacoemulsification (triple-DMEK). Exclusion criteria were previous eye surgery other than cataract surgery, loss of follow-up, any application of IOP-lowering medication before and after surgery, and low intraindividual repeatability of IOP measurements.
Purpose: In Descemet membrane endothelial keratoplasty (DMEK), lamellar splitting of the Descemet membrane (DM) may occur during stripping of host DM, leaving residual DM on the recipient's DMEK interface. The purpose of this study was to determine the incidence rate of lamellar splitting of DM during DMEK and to describe the ultrastructure of DM in these eyes.
Design: Retrospective consecutive case series.