PhD students
Current PhD projects
Indre Vasiliauskaite
In her PhD thesis, Indre focuses on assessing clinical outcomes and graft survival after Descemet membrane endothelial keratoplasty (DMEK). Indre is especially looking into the long-term (10 years) graft survival after DMEK and how graft survival is affected by early endothelial cell density decrease after DMEK. Furthermore, Indre is also evaluating the effect of donor parameters such as donor sepsis and post-DMEK ocular procedures such as phacoemulsification after phakic DMEK on endothelial cell densities outcomes after DMEK. Another thesis aspect is the impact of early graft detachment on DMEK outcomes.
Click here for the published articles of Indre.
PhD promotor: Prof. Dr. Martine Jager (Leiden University)
Co-promotors: Dr. Silke Oellerich and Dr. Gerrit Melles
Finalized PhD projects
Alina Miron
Elucidation of the migratory behaviour of the corneal endothelium
The thesis focuses on the in vivo and in vitro behavior of corneal endothelial cells before and after endothelial keratoplasty. The first part of the project concentrates on the ECD decrease after DMEK and DMEK graft viability prior to transplantation. The second part focusses on regenerative strategies for the treatment of FECD by developing and applying in vitro cell migration assays. In vitro cell migration from DMEK grafts of various sizes and shapes are investigated in a 3D cell culture system aiming to identify critical parameters for the successful clinical application of corneal endothelial therapies.
Click here to read the complete thesis.
PhD promotor: Prof. Dr. Martine Jager (Leiden University)
Co-promotors: Dr. Silke Oellerich and Dr. Gerrit Melles
Date of PhD defence: March 9, 2023
Lamis Baydoun
Descemet membrane endothelial keratoplasty: graft rejection, failure, and survival
Within the past two decades, full thickness penetrating keratoplasty (PK) has been largely supplanted by lamellar endothelial keratoplasty (EK) procedures that have revolutionized the treatment of corneal endothelial diseases such as Fuchs endothelial dystrophy. Since the introduction of EK in 1998, these techniques have undergone continuous transition, from Deep lamellar endothelial keratoplasty (DLEK) to Descemet stripping (automated) endothelial keratoplasty (DSEK/DSAEK) and eventually to Descemet membrane endothelial keratoplasty (DMEK). While the graft in DLEK and DSEK/DSAEK consists of endothelium, Descemet membrane and stroma, in DMEK only an isolated Descemet membrane with its endothelium, devoid of stroma, is transplanted. Notably, the thinner graft used in DMEK may have three main advantages over earlier techniques: Faster and better visual rehabilitation, predictable small refractive change, and a reduced risk of immunologic reactions. This thesis will investigate the clinical outcomes after DMEK, the latest refinement of lamellar endothelial keratoplasty techniques. The focus will be on DMEK graft survival and on allograft rejection (and its prediction), a complication that may potentially lead to graft failure and hereby reduce the overall survival probability.
Click here to read the complete thesis.
PhD promotor: Prof. Dr. Martine Jager (Leiden University)
Co-promotor: Dr. Gerrit Melles
Date of PhD defence: December 1, 2021
Daniele Spinozzi
Transplantation of cultured corneal endothelial cells: towards clinical application
Corneal transplantation still represents the elected method for the treatment of corneal endothelial pathologies. However, the worldwide shortage of donor corneas induced the exploration of approaches to use the donor tissue more efficiently or to be more independent from donor tissue. In his thesis, Daniele illustrated the improvements of new strategies for cell-based corneal endothelial regeneration, alternative to corneal endothelial surgical transplantation, by bridging the gap between in vitro experiments and clinical models. In the studies described, he addressed the establishment of a GMP-compliant protocol for in vitro hCEC culture for clinical application and then focused on endothelial cell sheet transplantation, describing both in vitro and in vivo applications of expanded CEC-carriers constructs made by biocompatible materials. This PhD project was part of the Horizon 2020 EU Consortium ARREST BLINDNESS.
Click here to read the complete thesis.
PhD promotor: Prof. Dr. Martine Jager (Leiden University)
Co-promotors: Dr. Silke Oellerich and Dr. Gerrit Melles
Date of PhD defence: November 17, 2020
Rénuka Birbal
Advances in endothelial keratoplasty
Corneal diseases are among the leading causes of reversible blindness worldwide. When conservative treatment options fail, many eyes can be treated with corneal transplantation. Historically, full thickness corneal transplantation, in which all corneal layers are replaced, has been the mainstay of care in the treatment of corneal endothelial disorders. In the past two decades, however, there has been a trend towards the selective, less invasive replacement of only the diseased, rather than all corneal layers. These partial thickness corneal transplantations are known as lamellar keratoplasties. Lamellar keratoplasty has significantly improved the clinical outcomes, such as visual acuity, after transplantation. Since its introduction in 1998, lamellar keratoplasty has evolved from Deep lamellar endothelial keratoplasty to Descemet membrane endothelial keratoplasty (DMEK). Globally, however, there is only one donor cornea available for 70 people in need. This shortage inspired further refinement of conventional DMEK and led to the development of adapted DMEK-techniques, which may increase the availability of endothelial donor grafts. This thesis focused on donor tissue preparation for DMEK and evaluates the feasibility and clinical outcomes of DMEK, DMET, Hemi-DMEK and Quarter-DMEK in the management of corneal endothelial disorders.
Click here to read the complete thesis.
PhD promotor: Prof. Dr. Martine Jager (Leiden University)
Co-promotor: Dr. Gerrit Melles
Date of PhD defence: November 17, 2020
Korine van Dijk
Clinical outcomes of modern lamellar keratoplasty techniques
After penetrating keratoplasty had been the preferred method for the treatment of corneal disorders for almost a century, the introduction of lamellar keratoplasty techniques has changed the field of corneal transplantation substantially over the last two decades. These lamellar keratoplasty techniques provide several advantages over penetrating keratoplasty: anterior lamellar keratoplasty may potentially improve graft survival by preserving the healthy recipient endothelium in the management of corneal stromal diseases, and endothelial keratoplasty has improved the predictability and speed of visual rehabilitation for treating endothelial disorders, mainly by leaving the anterior corneal surface intact. The latest innovation in the field of endothelial keratoplasty is Descemet membrane endothelial keratoplasty (DMEK), in which only the Descemet membrane and endothelium are replaced by donor tissue. The trend towards more selective and minimally invasive transplantation techniques has also led to the development of new treatment options for patients with (advanced) keratoconus, including the mid-stromal implantation of an isolated donor Bowman layer, referred to as Bowman layer-transplantation. This thesis focused on the feasibility and clinical outcomes of these two modern lamellar keratoplasty techniques, i.e. DMEK for endothelial disorders, and Bowman layer-transplantation for advanced keratoconus.
Click here to read the complete thesis.
PhD promotor: Prof. Dr. Martine Jager (Leiden University)
Co-promotor: Dr. Gerrit Melles
Date of PhD defence: January 16, 2018
Jack Parker
Recent innovations in minimally invasive anterior and posterior lamellar keratoplasty
For nearly a century, the definitive treatment of many corneal dystrophies and ectactic disorders were limited to penetrating keratoplasty, but over the past two decades, a surge of surgical innovation has propelled the treatment of many corneal diseases to more targeted approaches with significantly better visual outcomes. This thesis focused on the clinical outcomes of the rapid innovations for surgical treatment of corneal diseases, spanning from endothelial keratoplasty Bowman layer transplantation, highlighting key steps which may be moving us closer to a “post-keratoplasty” world.
Click here to read the complete thesis.
PhD promotor: Prof. Dr. Martine Jager (Leiden University)
Co-promotor: Dr. Gerrit Melles
Date of PhD defence: July 4, 2017
Lisanne Ham
Descement membrane endothelial keratoplasty – Donor tissue preparation and clinical outcomes
The first DMEK surgery was performed in 2006. The focus of this thesis was on the donor graft preparation technique and the postoperative outcomes of this new corneal transplantation technique. Clinical outcomes after DMEK were analyzed in terms of visual rehabilitation, endothelial cell density, refractive change and stability, and postoperative complications. New perspectives offered by DMEK were compared to the earlier corneal transplantation techniques.
Click here for the published articles of Lisanne.
PhD promotor: Prof. Dr. Jorge Alío
Co-promotor: Dr. Gerrit Melles
Date of PhD defence: May 14, 2012
Isabel Dapena
Descement membrane endothelial keratoplasty – Surgical technique, results and complications
Descemet membrane endothelial keratoplasty (DMEK) was the latest refinement of the endothelial keratoplasty techniques. The focus of this thesis was to describe the standardization of the surgical technique and to assess and evaluate the postoperative results of the standardized ‘no-touch’ DMEK technique. In addition the association of surgical-related aspects, including the surgeon’s learning curve, with postoperative outcomes was evaluated.
Click here for the published articles of Isabel.
PhD promotor: Prof. Dr. Jorge Alío
Co-promotor: Dr. Gerrit Melles
Date of PhD defence: May 14, 2012