PURPOSE: To report a patient with a pseudophakic bullous keratopathy (PBK) who underwent Descemet's membrane stripping endothelial keratoplasty (DSEK) with manual preparation of the donor corneal graft.CASE SUMMARY: A 61-year-old female presented with visual disturbance in her right eye. Five months prior, she was treated with phacoemulsification and intraocular lens exchange surgery of the right eye, and a very severe corneal edema was revealed by slit-lamp examination. We diagnosed PBK and planned DSEK with manual preparation of a donor corneal graft because of the non-availability of a microkeratome or a femtosecond laser. After making the corneal graft using an artificial anterior chamber, crescent knife and cornea dissector, the keratoplasty proceeded using the graft. Three months after surgery, her graft was well-maintained on the right eye. The patient's visual acuity was 0.3, and the corneal endothelial cell count was 1,844/mm².CONCLUSIONS: Manual preparation of the donor corneal graft for DSEK is suitable as a second choice treatment method when the availability of surgical devices is limited.
Anterior Chamber ; Cornea ; Corneal Edema ; Corneal Transplantation ; Descemet Membrane ; Endothelial Cells ; Female ; Humans ; Lenses, Intraocular ; Methods ; Middle Aged ; Phacoemulsification ; Tissue Donors ; Transplants ; Visual Acuity

corneal graft survival following primary penetrating keratoplasty (PK) with imported donor corneas.METHODS: The eyes of patients who underwent primary PK with imported donor corneas were classified retrospectively into two groups according to a donor-age cutoff of 65 years. Primary outcome measures were rejection-free graft survival and graft survival. Cox proportional hazard regression analysis was used to assess the factors affecting graft survival. Survival analysis was performed using the Kaplan-Meier method, while differences between groups were examined using a log-rank test. A subgroup analysis of low- and high-risk eyes according to preoperative diagnosis was also performed.RESULTS: A total of 140 eyes from 138 patients (age, 58 ± 18 years) were enrolled. Cox regression analysis revealed that the donor age of 65 years or older group presented an increased risk of both graft rejection and failure. Survival analysis revealed that rejection-free graft survival and graft survival rates were higher in eyes in the donor age of less than 65 years group. Finally, in the subgroup analysis, both rejection-free graft survival and graft survival rates were significantly higher in the donor age of less than 65 years group than in the donor age of 65 years or older group, but only in the low-risk subgroup.CONCLUSIONS: Donor age may correlate with graft survival in primary PK performed with imported donor corneas. Donor age could be a considerable factor in primary PK with imported donor corneas, especially in preoperatively low-risk patients.]]>
Cornea ; Corneal Transplantation ; Diagnosis ; Graft Rejection ; Graft Survival ; Humans ; Keratoplasty, Penetrating ; Methods ; Outcome Assessment (Health Care) ; Retrospective Studies ; Risk Factors ; Tissue Donors ; Transplants

Keratoplasty, which is cornea transplant surgery, is one of the treatment methods for patients with turbidity or keratitis. Recently, keratoplasty using a surgical robot was studied to increase precision. In this study, the effect of surgical factors on the deformation and curvature of the cornea were analyzed in order to improve the accuracy of keratoplasty and derive the optimal surgical factors using finite element method (FEM). Suturing tension and depth were selected as surgical factors. An FEM model, a constitutive equation, and boundary conditions were determined using experiments and reference data. Suturing tension significantly impacted deformation and curvature change, and suturing depth affected the position of the thread-cornea contact point. Both factors have a significant impact on a focal point in the retina and the patient's visual acuity after keratoplasty.
Cornea ; Corneal Transplantation ; Finite Element Analysis ; Humans ; Keratitis ; Methods ; Retina ; Visual Acuity

Presbyopia is an age-related condition that progressively decreases the ability to focus on near objects. Minimally invasive surgical techniques have been developed to improve near vision, including laser in situ keratomileuses (LASIK) and corneal inlay. Most have similar approaches using monovision or increasing the depth of focus. Monovision laser refractive surgery is a combination of conventional LASIK, LASIK which creates a multifocal cornea (central near or peripheral near) and aspheric micro-monovision LASIK with a special ablation profile, which develops spherical aberration. Conductive keratoplasty is a method that uses radiofrequency energy to shrink the mid-peripheral corneal stromal tissue. However, it is not used because of regression. A corneal inlay is a small device that is implanted in the corneal flap or pocket made by a femtosecond laser. It is inserted into the non-dominant eye. There are various inlays such as the Flexivue Microlens (refractive), Raindrop (corneal shape-changing), and KAMRA (small-aperture) inlays. However, the safety and effectiveness of these inlays have not been proven over a long follow-up period, so care is required when performing inlay implantation. All presbyopia treatments can improve near vision but also have limitations and side effects such as reduced far vision, contrast sensitivity, or increased glare. Therefore, it is essential to select patients carefully. Mechanisms associated with presbyopia are not fully understood, and presbyopia remains challenging for ophthalmologists.
Contrast Sensitivity ; Cornea ; Corneal Transplantation ; Follow-Up Studies ; Glare ; Humans ; Inlays ; Keratomileusis, Laser In Situ ; Methods ; Presbyopia ; Refractive Surgical Procedures ; Vision, Monocular

OBJECTIVE: To investigate the effects of corneal thickness distribution and apex position on postoperative refractive status after full-bed deep anterior lamellar keratoplasty (FBDALK). METHODS: This is a retrospective analysis of patients who were diagnosed with advanced keratoconus between 2011 and 2014 in our hospital. The base of the cone in all patients did not exceed the central cornea at a 6-mm range. The FBDALK was performed by a same surgeon. All patients had a complete corneal suture removal and the follow-up records were intact. Patients who had graft-bed misalignment or who were complicated with a cataract or glaucoma were excluded. Uncorrected visual acuity (UCVA), best spectacle corrected visual acuity (BSCVA), and Pentacam examination data were recorded at two years postoperatively. The recorded data included the superior-inferior (S-I) and nasal-temporal (N-T) corneal thickness differences in 2, 4, 6, and 8 mm diameter concentric circles with the corneal apex as the center (S-I_{2 mm}, S-I_{4 mm}, S-I_{6 mm}, S-I_{8 mm}, N-T_{2 mm}, N-T_{4 mm}, N-T_{6 mm}, and N-T_{8 mm}), the linear, X-axis, and Y-axis distance between the corneal pupillary center and the cornea apex, total corneal astigmatism at a zone of 3 mm diameter from the corneal apex (TA_{3 mm}), the astigmatic vector values J₀ and J₄₅, and the corneal total higher-order aberration for 3 and 6 mm pupil diameters (HOA_{3 mm} and HOA_{6 mm}). Statistical analysis was performed by SPSS 15.0. RESULTS: A total of 47 eyes of 46 patients met the criteria and were included in this study. The mean follow-up time was (28±7) months. The mean UCVA was 0.45±0.23 (logMAR) (MAR: minimum angle of resolution) and the mean BSCVA was 0.19±0.15 (logMAR), which were all significantly positively correlated with postoperative TA_{3 mm} and HOA_{3 mm}. The mean S-I corneal thickness differences were (44.62±37.74) μm, and the mean N-T was (38.57±32.29) μm. S-I_{2 mm} was significantly positively correlated with J₀ (r=0.31), J₄₅ (r=0.42), HOA_{3 mm} (r=0.37), and HOA_{6 mm} (r=0.48). S-I_{4 mm} and S-I_{8 mm} were significantly positively correlated with HOA_{3 mm} (r=0.30, r=0.40) and HOA_{6 mm} (r=0.46, r=0.35). The X-axis distance between corneal pupillary center and corneal apex was significantly positively correlated with J₄₅ (r=0.29). CONCLUSIONS In patients with advanced keratoconus after FBDALK, the unevenly distributed thickness at corneal pupillary area and the misalignment of corneal apex and pupillary center might cause significant regular and irregular astigmatism, which affected the postoperative visual quality.
Adolescent ; Adult ; Cornea/surgery* ; Corneal Transplantation/methods* ; Cryopreservation ; Female ; Follow-Up Studies ; Humans ; Keratoconus/diagnosis* ; Keratoplasty, Penetrating/methods* ; Male ; Retrospective Studies ; Visual Acuity ; Young Adult

We describe herein a case of an impending corneal perforation with a large descemetocele in a patient with previous penetrating keratoplasty (PKP) that subsequently was treated with an emergent lamellar keratoplasty using frozen preserved cornea. A 76-year-old male patient, who had a PKP, presented with a completely whitish and edematous graft accompanied by large epithelial defects. Although antibiotics and antiviral agents were tried for three days, the corneal stroma abruptly melted, except for the Descemet's membrane and endothelium. Cryopreserved corneal tissue that was kept at -80degrees C was thawed and sutured on top of the remaining Descemet's membrane and endothelium. Pathological and microbiological tests were conducted using the remaining donor and recipient corneal tissues. After tectonic corneal transplantation on top of a large descemetocele, a healthy graft and relatively clear interfaces between graft-host junctions were maintained without serious adverse reactions throughout 6 month follow-up period. Microbiological evaluations of donor tissue at the time of thawing and tissue preparation were done, and the results were all negative. Tissue that was taken intraoperatively from the recipient cornea also showed negative microbiological results. In conclusion, tectonic lamellar keratoplasty, using cryopreserved corneal tissue, only onto the remaining Descemet's membrane and endothelium in an emergent condition, was a safe and effective treatment.
Cornea/*surgery ; Corneal Perforation/pathology/physiopathology/*surgery ; Corneal Transplantation/*methods ; *Cryopreservation ; Eye Injuries, Penetrating/pathology/physiopathology/*surgery ; Female ; Humans ; Keratoplasty, Penetrating ; Male ; Middle Aged ; *Tissue Donors ; Treatment Outcome ; Visual Acuity

Artificial corneas have been developed as an alternative to natural donor tissue to replace damaged or diseased corneas. This study was conducted to evaluate the stability and biocompatibility of PHEMA-PMMA [poly (2-hydroxyl methacrylate)-poly (methyl methacrylate)] keratoprostheses in rabbits following penetrating keratoplasty. Sixteen male New Zealand White rabbits aged 16 weeks were divided into three groups. Group I and group II contained six rabbits each, while the control group had four rabbits. Experimental surgery was conducted under general anesthesia. The cornea was penetrated using an 8 mm diameter biopsy punch. In group I (core 5 mm & skirt 3 mm) and group II (core 6 mm & skirt 2 mm), the keratoprosthesis was placed into the recipient full thickness bed and sutured into position with double-layer continuous. In the control group, corneal transplantation using normal allogenic corneal tissue was performed with the same suture method. After four and eight weeks, keratoprosthesis devices were evaluated by histopathological analysis of gross lesions. Post-operative complications were observed, such as extrusion and infection in experimental groups. Most corneas were maintained in the defect site by double-layer continuous suture materials for 4 weeks and kept good light transmission. However, most artificial cornea were extruded before 8 weeks. Overall, combined PHEMA and PMMA appears to have sufficient advantages for production of artificial corneas because of its optical transparency, flexibility and other mechanical features. However, the stability and biocompatibility were not sufficient to enable application in humans and animals at the present time using penetrating keratoplasty. Further studies are essential to improve the stability and biocompatibility with or without other types of keratoplasty.
Anesthesia, General ; Animals ; Biopsy ; Cornea ; Corneal Transplantation ; Humans ; Keratoplasty, Penetrating* ; Male ; Methods ; Pliability ; Polyhydroxyethyl Methacrylate ; Polymethyl Methacrylate ; Rabbits* ; Sutures ; Tissue Donors

BACKGROUNDSmall incision refractive lenticule extraction (SMILE) is an effective laser procedure that treats myopia. This research was to describe a novel approach to treat corneal ulcer or perforation using the corneal lenticules obtained from SMILE and to evaluate the safety and effectiveness of tectonic keratoplasty with femtosecond laser intrastromal lenticule (TEKIL).

METHODSA total of twenty patients (22 eyes) were monitored for at least 6 months and were assessed using slit lamp microscopy, optical coherence tomography, and best-corrected visual acuity (BCVA). Postoperative complications throughout the study period were recorded.

RESULTSCorneal ulcer in 14 patients (16 eyes) and corneal perforation in six patients (6 eyes) were treated with TEKIL. The patients were ten females and ten males, with a mean age of 58.5 ± 16.3 years (range: 16-81 years). In this study, the most causes of corneal ulcer or perforation were immunologic causes (54.5%). After TEKIL procedure, global integrity was achieved in all cases. No immune rejection or perforation was detected. The mean BCVA improved from 0.17 ± 0.20 preoperatively to 0.27 ± 0.25 postoperatively at the final follow-up (t = 2.095, P = 0.052). The postoperative BCVA improved in 12 eyes (54.5%) and maintained in nine eyes (40.9%). Vision function successfully maintained in all eyes (100%). In three cases, corneal ulcers were treated by reoperation of TEKIL at 3 months after the initial surgery for the reason that the residual corneal thickness was <250 μm.

CONCLUSIONSTEKIL seems to be an effective treatment for corneal ulcer and perforation in the condition of emergency and donor shortage.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Cornea ; surgery ; Corneal Perforation ; physiopathology ; surgery ; Corneal Transplantation ; adverse effects ; methods ; Corneal Ulcer ; physiopathology ; surgery ; Female ; Humans ; Male ; Middle Aged ; Postoperative Complications ; Retrospective Studies ; Tomography, Optical Coherence ; Visual Acuity ; physiology ; Young Adult

PURPOSE: To report the clinical outcomes of deep anterior lamellar keratoplasty (DALK) when sterile gamma-irradiated acellular corneal tissues (VisionGraft) are used in combination with amniotic membrane transplantation (AMT) for intractable ocular surface diseases. METHODS: The medical records of fifteen patients who had DALK with AMT were retrospectively reviewed. Indications for surgery included ocular burn, bacterial keratitis, herpes simplex virus keratitis, corneal opacity with Stevens-Johnson syndrome, Mooren's ulcer, idiopathic myxoid degeneration of corneal stroma, and recurrent band keratopathy. DALK was performed using partial-thickness acellular corneal tissue and a temporary amniotic membrane patch was added at the end of the operation. RESULTS: All cases that underwent DALK with AMT became epithelialized within 2 postoperative weeks. Twelve patients showed favorable outcomes without graft rejection, corneal opacification, or neovascularization. The other three grafts developed corneal opacification and neovascularization, and required additional penetrating keratoplasty (PK). Unlike the results of previous PKs, there were no graft rejections and the graft clarity was well-maintained in these three cases for at least 8 months after PK. CONCLUSIONS: DALK using sterile acellular corneal tissues in combination with AMT may be a good therapeutic strategy for treating intractable ocular surface diseases because of lowered immune rejection, fibroblast activation, and facilitation of epithelialization. Furthermore, DALK can help stabilize the ocular surface, prolong graft survival, and may allow better outcomes when combined with subsequent PK.
Adult ; Aged ; Amnion/*transplantation ; Corneal Diseases/pathology/*surgery ; Corneal Stroma/radiation effects/*transplantation ; Female ; Graft Survival ; Humans ; Keratoplasty, Penetrating/*methods ; Male ; Middle Aged ; Retrospective Studies ; Visual Acuity ; Young Adult

BACKGROUNDThe limiting factor to corneal transplantation is the availability of donors. Research has suggested that xenogenic acellular corneal scaffolds (XACS) may be a possible alternative to transplantation. This study aimed to investigate the viability of performing lamellar corneal transplantation (LCT) in rabbits using canine XACS.

METHODSFresh dog corneas were decellularized by serial digestion, and LCT was performed on rabbit eyes using xenogeneic decellularized corneal matrix. Cellular and morphological changes were observed by slit-lamp, light, and scanning electron microscopy at 7, 30 and 90 days postoperatively. Immunocytochemical staining for specific markers such as keratin 3, vimentin and MUC5AC, was used to identify cells in the graft.

RESULTSDecellularized xenogenic corneal matrix remained transparent for about 1-month after LCT. The recipient cells were able to survive and proliferate into the grafts. Three months after transplantation, grafts had merged with host tissue, and graft epithelialization and vascularization had occurred. Corneal nerve fibers were able to grow into the graft in rabbits transplanted with XACS.

CONCLUSIONSXenogenic acellular corneal scaffolds can maintain the transparency of corneal grafts about 1-month and permit growth of cells and nerve fibers, and is, therefore, a potential substitute or carrier for a replacement cornea.

Animals ; Cornea ; surgery ; Corneal Stroma ; surgery ; Corneal Transplantation ; methods ; Dogs ; Microscopy, Confocal ; Rabbits ; Tissue Engineering