Full-thickness Penetrating Keratoplasty Research Articles

Gelatinous Drop-Like Corneal Dystrophy in an Acehnese Family: Serial Cases.

Introduction : Gelatinous drop-like dystrophy (GDLD) is a rare type of corneal dystrophy with an autosomal recessive inheritance pattern. Although the prevalence in Japan is approximately 1 in 33,000, it is much less common in other nations. Lamellar or penetrating keratoplasty is needed for most patients to alleviate the symptoms. This case series aims to provide knowledge regarding rare cases of GDLD and its management.
 Case Illustration : Three male siblings from consanguineous marriage were found to have corneal dystrophy, characterized by a white-yellow nodular lesion with a kumquat-like appearance on the corneal surface. The visual acuity of each patient was light perception with good projection. To treat the condition, all patients underwent full-thickness penetrating keratoplasty. One month after the procedure, their visual acuity had improved to 3/60, 2/60, and 2/60, respectively.
 Discussion : GDLD is a genetic disease with gelatinous amyloid deposits in the cornea that typically manifests within the first decades of life. GDLD can present in three different phenotypes, including band keratopathy, mulberry, and kumquat-like appearance. In the case of these siblings, they have developed the severe kumquat-like phenotype. Detection by examining family involvement and the cornea's clinical presentation can help diagnose GDLD. Full-thickness penetrating keratoplasty can be an option for managing severely impaired visual acuity caused by GDLD.
 Conclusion : GDLD is a rare corneal dystrophy that can lead to severe visual impairment. The objective of treating GDLD is to enhance vision and prevent its progression. Vision loss can be alleviated througha surgical procedure such as full-thickness penetrating keratoplasty.

Intraoperative collagen imaging of sutured cornea: A way towards managing post-penetrating keratoplasty astigmatism

The birefringent nature of the human cornea plays an important role in comprehending its structural behavior in both diseased and surgical conditions. During corneal transplantation, irregular astigmatism is a common post-surgical complication that depends on the characteristics of suturing. Four human cadaver corneas are subjected to an in-vitro model of a typical full-thickness penetrating keratoplasty (PK) procedure using 16 simple interrupted 10–0 vicyrl sutures. The birefringence of these four corneas is analyzed using digital photoelasticity and compared with the control cornea (without PK). It is found that the sutures and their mutual interaction influence the morphology of the peripheral birefringence of the cornea. The findings of the present investigation are pertinent to intraoperative suture management during PK. Results suggest conserving the typical diamond-shaped morphology of peripheral birefringence would ensure uniform distribution of sutures. Therefore, birefringence imaging could be useful in suture management to ensure proper apposition of the graft-host junction, thus minimizing the risk of irregular astigmatism.

Questionable effect of collagen cross-linking for keratoconus in a pregnant female

We report a rare case of keratoconus (KC) progressing to advanced stage in a pregnant female with previously stable KC managed with collagen cross-linking 7 years back. A 26-year-old female first visited during the second month of her pregnancy with stable KC managed with collagen cross-linking 7 years back. She was found to have corneal melt with haze and was advised to undergo keratoplasty surgery. However, the patient was not willing for that, and the surgery was deferred. After 4 months, the patient came with similar complaints. On examination, the corneal melt was advanced and the patient was suggested surgery again. However, she again deferred the surgery. At the eighth month of pregnancy, the patient came with advanced melt with well-epithelized descemetocele, which was then successfully operated on an emergency basis with full-thickness penetrating keratoplasty.

The Effects of Donor-Recipient Age and Sex Compatibility in the Outcomes of Deep Anterior Lamellar Keratoplasties.

PurposeCorneal transplantations are the commonest allogenic transplant surgeries performed worldwide. Transplantable grade donor cornea is a finite resource. There is thus an impetus for eye banks to optimize the use of each harvested cornea, and clinicians to minimize the risks of graft rejection and failure. With better survival and lower rejection rates, anterior lamellar keratoplasty has gained popularity as an alternative technique to full-thickness penetrating keratoplasty, for the treatment of corneal stromal diseases. This study evaluated the effects of donor-recipient age- and sex-matching on the outcomes of eyes that had undergone deep anterior lamellar keratoplasty (DALK) surgeries.DesignObservational cross-sectional study (national corneal graft registry data).SubjectsAll DALK surgeries performed in a tertiary ophthalmic hospital over an 11-year period.MethodsTo analyse the effects of donor-recipient sex-matching, transplantations were classified as “presumed H-Y incompatible” (male donor to female recipient) or “presumed H-Y compatible” (all other donor-recipient sex combinations). For age-matching, differences in donor and recipient ages were calculated. Cox proportional hazards regressions were used to evaluate the influence of donor-recipient sex-matching and age-matching on graft failure and rejection.Main Outcome MeasuresRates of graft failure and rejection within each group.Results401 eyes were included. 271 (67.6%) transplants were presumed H-Y compatible. 29 (7.2%) grafts failed and 9 (2.2%) grafts rejected. There were trends of lower hazard ratios (HRs) in graft failure and rejection in the presumed H-Y compatible group [HRs: 0.59 (95% CI 0.20–1.77, p = 0.34) and 0.93 (95% CI 0.22–3.89, p = 0.926), respectively]. Median difference in age between recipients and donors was 15.0 years (IQR −2.8–34.3). The HRs of graft failure and rejection were not influenced by donor-recipient age [HRs per 1-year increase in age difference: 0.995 (95% CI 0.98–1.01, p = 0.483) and 1.01 (95% CI 0.99–1.03, p = 0.394), respectively].ConclusionIn eyes that had undergone DALK surgeries, no significant influence of donor-recipient sex- or age-matching on graft rejection and failure was observed. Without strong evidence and the limitations of obtaining sample sizes required for an adequately powered study, the benefits of sex- and age-matching of donors and recipients during graft allocation for DALK surgeries is currently inconclusive.

Absent Red Reflexes and Cloudy Corneas.

Absent Red Reflexes and Cloudy Corneas.

Effect of a Multidisciplinary Educational Course on Health Literacy and Satisfaction of Patients Undergoing Keratoplasty

Background: Keratoplasty is a surgical procedure in which part or all of a damaged or diseased cornea is replaced by healthy corneal tissue from a donor. The study aimed to evaluate the effect of a multidisciplinary education course on the health literacy and satisfaction of patients undergoing keratoplasty. This study was carried out at the Ophthalmology department and outpatient clinics at Assiut University hospital. The sample of the study was a purposive sample of 60 adult and elderly patients (30 study group and 30 for the control group) undergoing corneal transplantation surgery. Tools of data collection included four tools, (1) patient’s interview questionnaire sheet, (2) patient's knowledge assessment & observation checklist, (3) health literacy questionnaire, (4) patient satisfaction with nursing care quality questionnaire. The main results of this study revealed the majority of patients in the two groups were diagnosed with keratoconus, performed Full-thickness (penetrating) keratoplasty for optical reasons. There was a highly statistically significant difference between both the study and control of patients regarding health literacy score. Half of the patients in the control group have poor satisfaction level while the majority of the study group patients (83.3%) have a very good satisfaction level post educational course application. There was a positive correlation between patients’ knowledge & health literacy and patient satisfaction (P. <0.001). The main recommendation is to establish a patient education center in the ophthalmology department to provide patients with the needed information before performing the keratoplasty.

Term Newborn with Corneal Opacity.

Term Newborn with Corneal Opacity.

Cost analysis of eye bank versus surgeon prepared endothelial grafts

BackgroundSelective lamellar corneal transplantation (keratoplasty) has overtaken full thickness penetrating keratoplasty as the graft choice for endothelial failure. Even more recently eye bank prepared tissues are becoming increasing popular as a way to reduce the risks of tissue loss and stress during endothelial keratoplasty preparation in the surgical theatre. This study compares costs between surgeon and eye bank prepared tissues for Descemet’s stripping automated endothelial keratoplasty (DSAEK) and Descemet’s membrane endothelial keratoplasty (DMEK).MethodsRetrospective study conducted at the Royal Liverpool University Hospital including endothelial keratoplasties with a minimum of 6 months follow-up time. Cost analysis included surgical expenses, tissue acquisition fees, cost of patient’s ward admission and out-patient expenses, including cost of re-bubbling procedures, costs of visits, anterior segment imaging and optometrist visits within the first 6 months follow-up.ResultsNinety-eight eyes of 98 patients were included in the study of which 42 underwent DSAEK surgery and 56 DMEK surgery. Cost analysis of surgical expenses in the DSAEK group showed a significant difference between using surgeon prepared and eye bank prepared tissue (£3866 ± 296 and £4389 ± 360, respectively; p < 0.01) and the same was found in the DMEK group (£3682 ± 167 and £4162 ± 167 for surgeon prepared and eye bank prepared tissues, respectively; p < 0.01). Cost of out-patient visits did not differ significantly in either group.ConclusionsAt the Royal Liverpool University Hospital, eye bank prepared tissues had higher surgical expenses compared to those prepared by the surgeon, while the post-operative care expenses were similar between the two groups.

TEMPORARY KERATOPROSTHESIS WITH PENETRATING KERATOPLASTY IN CONJUNCTION WITH PARS PLANA VITRECTOMY FOR REPAIR OF RETINAL DETACHMENTS IN PATIENTS WITH ANTERIOR AND POSTERIOR SEGMENT PATHOLOGY.

To review the visual and anatomical outcomes of combined anterior and posterior segment surgery for retinal detachment repair. Eight patients with combined retinal and corneal disease underwent combined temporary keratoprosthesis with penetrating keratoplasty combined with pars plana vitrectomy for retinal detachment repair with silicone oil tamponade. Visual and anatomical outcomes were reviewed retrospectively. Follow-up ranged from 12 months to 37 months. Preoperative visual acuity ranged from light perception to hand motion. All but one case had proliferative vitreoretinopathy present at the time of surgery. Postoperative visual acuity ranged from hand motion to light perception. At the most recent follow-up visit, all of the patients had attached retinas, no patients had phthisis bulbi, and all but one patient had a clear cornea. However, 3 of these cases (38%) required repeat retinal detachment repair and one of them also required repeat penetrating keratoplasty, which was performed at the time of retinal repair. Combined full-thickness penetrating keratoplasty and retinal detachment repair has good anatomical outcomes and is an efficient way to treat complex anterior and posterior segment abnormality. Although postoperative visual function is limited; almost all patients were agreeable to repeat surgery if they were presented with the choice again.

Full thickness penetrating keratoplasty with cataract extraction and intraocular lens implantation in leprosy patients

Full thickness penetrating keratoplasty with cataract extraction and intraocular lens implantation in leprosy patients

Developmental glaucoma in a patient of ectrodactyly-ectodermal dysplasia.

A 23-year-old Indian female, already on intraocular pressure (IOP) lowering eye drops was referred for control of IOP. Systemic involvement was marked for coarse facial features [Fig. 1a], dental and skeletal abnormalities [Fig. 1c-g] suggestive of ectrodactyly-ectodermal dysplasia (EED). The right eye was in exotropia with no perception of light. The left eye had generalized nebular corneal opacification [Fig. 1b], wide-angle recess with numerous iris processes on gonioscopy, and visual acuity of 20/800. Applanation IOP was 28 mm Hg in the right eye and 46 mm Hg in left eye. Pachymetry and axial lengths were 523 μm and 24.32 mm, respectively in the left eye. Hazy view of fundus revealed glaucomatous optic disc changes.Figure 1: (a) Coarse facial features. (b) Dense corneal opacity in the right eye and the left eye with hazy cornea. (c) Oligodontia. (d) Orthopantomograph showing oligodontia with underdeveloped alveolar bone. (e and f) Ectrodactyly of hands. (g) Ectrodactyly and syndactyly of feetAfter lowering IOP with oral acetazolamide, Ahmed glaucoma valve FP7 (New World Medical, Inc CA) was implanted in superotemporal quadrant. The tube was placed in in the anterior chamber. At 4 months, full-thickness penetrating keratoplasty (PK) was done. In the early postoperative period vision was 20/1000 and IOP varied between 6 to 9 mm Hg [Fig. 2a]. At 7 months follow-up after PK, best-corrected visual acuity (BCVA) was 20/80 [Fig. 2b]. The corneal graft was clear but cataractous changes were noticed [Fig. 2c]. The IOP was 16 mm Hg, and the tube was well placed in the anterior chamber [Fig. 2d] with diffuse functional bleb [Fig. 2e]. The left eye fundus examination revealed average-sized disc with vertical cup-to-disc ratio of 0.75 and inferior rim thinning [Fig. 2f]. At 18-month follow-up, graft was clear, BCVA was 20/50, and IOP was 16 mmHg.Figure 2: (a) Some edema of the graft 1-week post-keratoplasty (b) Clear graft at 7-month follow-up (c) Clinically significant cataract. (d) Ahmed glaucoma valve FP7 tube in situ (white arrow) in the anterior chamber. (e) Bleb (red arrow). (f) Fundus photo depicting glaucomatous cupping in the left eyeDiscussion The reported ocular involvement in EED includes telecanthus, blepharophimosis, entropion, meibomian gland absence, atresia of lacrimal outflow tract components, ocular surface and tear film disorders, and keratopathy.[12] Infantile glaucoma has been reported with ectodermal dysplasia.[3] The absence of iris anomalies and presence of ectrodactyly differentiate this case from Axenfeld-Rieger syndrome.[4] Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Combined Descemet membrane endothelial keratoplasty and extracapsular cataract extraction: management of an intraoperative challenge

Endothelial corneal transplantation (Descemet membrane endothelial keratoplasty [DMEK]) combined with cataract surgery as a triple procedure has been demonstrated to be safe and cost-effective. Where the corneal opacity is more significant, this may preclude safe phacoemulsification. This may not be apparent during preoperative assessment. An 80-year-old man with corneal decompensation secondary to herpes simplex endotheliitis and cataract underwent combined cataract extraction and DMEK. Intraoperatively, the surgical view became too poor to continue with conventional phacoemulsification. The lens was extracted by conversion to extracapsular surgery (extracapsular cataract extraction [ECCE]). Descemet membrane endothelial keratoplasty surgery was then completed without complication. Postoperatively, the graft remained attached, and by 3 months, acuity improved to 20/32 (Snellen). A poor intraoperative view during the triple procedure does not preclude a successful outcome. Corneal opacity can be overcome, avoiding full-thickness penetrating keratoplasty or discarding healthy graft tissue. Conversion to ECCE combined with DMEK is a feasible option intraoperatively that can still provide good outcomes.

Biocompatibility evaluation of bioprinted decellularized collagen sheet implanted in vivo cornea using swept-source optical coherence tomography.

Corneal transplantation by full‐thickness penetrating keratoplasty with human donor tissue is a widely accepted treatment for damaged or diseased corneas. Although corneal transplantation has a high success rate, a shortage of high‐quality donor tissue is a considerable limitation. Therefore, bioengineered corneas could be an effective solution for this limitation, and a decellularized extracellular matrix comprises a promising scaffold for their fabrication. In this study, three‐dimensional bioprinted decellularized collagen sheets were implanted into the stromal layer of the cornea of five rabbits. We performed in vivo noninvasive monitoring of the rabbit corneas using swept‐source optical coherence tomography (OCT) after implanting the collagen sheets. Anterior segment OCT images and averaged amplitude‐scans were acquired biweekly to monitor corneal thickness after implantation for 1 month. The averaged cornea thickness in the control images was 430.3 ± 5.9 μm, while the averaged thickness after corneal implantation was 598.5 ± 11.8 μm and 564.5 ± 12.5 μm at 2 and 4 weeks, respectively. The corneal thickness reduction of 34 μm confirmed the biocompatibility through the image analysis of the depth‐intensity profile base. Moreover, hematoxylin and eosin staining supported the biocompatibility evaluation of the bioprinted decellularized collagen sheet implantation. Hence, the developed bioprinted decellularized collagen sheets could become an alternative solution to human corneal donor tissue, and the proposed image analysis procedure could be beneficial to confirm the success of the surgery.

Endothelial corneal transplants: indications, clinical profile and surgical outcomes in a tertiary care hospital

BackgroundEndothelial keratoplasties have become the surgical procedure of choice over full thickness penetrating keratoplasty for corneal decompensation because of endothelial dysfunction. MethodsA retrospective data review was performed from February 2016 to April 2017 for all the patients who underwent endothelial keratoplasty in a tertiary care center for Indian Armed Forces. ResultsA total of 161 corneal transplants were performed; endothelial keratoplasties accounted for 34 (21.1%) transplants. Most common indication was pseudophakic/aphakic bullous keratopathy followed by Ahmed glaucoma valve–related corneal decompensation and Fuchs' corneal dystrophy, respectively. Mean preoperative corneal thickness was 845.96 ± 106.9 microns. Mean lenticule thickness was 131.55 ± 42.47 microns with microkeratome for descemet stripping automated endothelial keratoplasty (DSAEK) and 174 ± 70.4 microns manually for descemet stripping endothelial keratoplasty (DSEK). Mean preoperative best-corrected visual acuity (BCVA) was 1.65 LogMAR (Snellen equivalent in meters 2/60 approx) which significantly improved to 0.82 LogMAR (Snellen equivalent in meters 6/36 approx) after surgery. In the DSAEK group, BCVA improved from 1.61 to 0.7 LogMAR, whereas in the DSEK group, the visual acuity improved from 1.7 to 0.94 LogMAR at one-month postoperative period. Postoperatively, two patients had graft detachment and had to undergo repeat DSAEK. ConclusionStudy results suggest the similar trends in our tertiary care hospital as in other most advanced ophthalmic centers around the world for adoption of newer techniques of lamellar corneal transplants and their outcomes.

Non-related contact lens coinfection with Acanthamoeba and Fusarium

Rationale: Microbial keratitis caused by coinfection with more than one species of pathogens is a severe condition with an unfavorable prognosis. Patient concerns: An immunocompetent Nepali woman complained of pain in the left eye, redness, watering and decreased vision for 5 months. Interventions: The patient was discarded and accurately diagnosed with coinfection with Fusarium sp. and Acanthamoeba sp. The habit of washing the eyes with tap water from a domestic storage tank was the most likely source of infection since it was found to be contaminated with cysts of Acanthamoeba sp. The woman received eye drops of fluconazole and natamycin (5%), cefazoline (50 mg/mL), atropine, and tablets of itraconazole (100 mg), which were later switched to eye drops of clotrimazole (1%), natamycin (5%) and voriconazole (1%), and tablets of itraconazole. A full thickness penetrating keratoplasty was performed followed by treatment with eye drops of voriconazole (1%), natamet (5%), ofloxacin, atropine and carboxymethylcellulose for one week. Outcomes: After treatment, the condition of the patient significantly improved and was discharged one week after keratoplasty. Lessons: This is the first report of Acanthamoeba keratitis in Nepal and the first report of coinfection with Fusarium in this country and highlights the importance of early diagnosis of microbial keratitis both in single microorganism infections and coinfections, even in no contact lens wearers.

Corneal transplantation in the modern era.

Corneal blindness is one of the major causes of reversible blindness, which can be managed with transplantation of a healthy donor cornea. It is the most successful organ transplantation in the human body as cornea is devoid of vasculature, minimizing the risk of graft rejection. The first successful transplant was performed by Zirm, and since then, corneal transplantation has seen significant evolution. It has been possible because of the relentless efforts by researchers and the increase in knowledge about corneal anatomy, improvement in instruments and advancements in technology. Keratoplasty has come a long way since the initial surgeries wherein the whole cornea was replaced to the present day where only the selective diseased layer can be replaced. These newer procedures maintain structural integrity and avoid catastrophic complications associated with open globe surgery. Corneal transplantation procedures are broadly classified as full-thickness penetrating keratoplasty and partial lamellar corneal surgeries which include anterior lamellar keratoplasty [sperficial anterior lamellar keratoplasty (SALK), automated lamellar therapeutic keratoplasty (ALTK) and deep anterior lamellar keratoplasty (DALK)] and posterior lamellar keratoplasty [Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK)] broadly.

Etiology of Global Corneal Blindness and Current Practices of Corneal Transplantation: A Focused Review.

The purpose of this focused review was to explore the etiologies of corneal blindness worldwide and compare them with the indications and type of keratoplasties (eg, full-thickness penetrating keratoplasty, anterior lamellar keratoplasty, or endothelial keratoplasty) performed. A literature search of the articles published in the top 10 journals (based on the Altmetrics score) relevant to corneal transplantation within the past 20 years was performed to determine how the focus within corneal transplantation has changed over time. These data were compared with the prevalence and etiology of corneal blindness in each respective region worldwide. The leading etiologies of corneal blindness worldwide are primarily due to anterior corneal pathology with a normal endothelium, and the prevalence is highest in developing countries. In addition, the number and type of corneal transplantations performed globally indicate that current practices are disproportionately skewed in favor of endothelial keratoplasty, which is targeted for the pathology prevalent in developed countries. Despite the large number of individuals who would benefit from anterior lamellar keratoplasty, this technique seems to be infrequently performed. Most corneal blindness worldwide is secondary to anterior corneal pathology because of infections and trauma. However, this does not align with the current trends and practices in the field of corneal transplantation. We discuss potential solutions to address the current leading causes of global corneal blindness, including increasing the number of anterior lamellar keratoplasties performed, using long-term preserved corneas by trained surgeons, and improving eye bank handling and distribution of procured tissues.

New trends in corneal transplants at the University of Toronto

ObjectiveTo assess trends in surgical procedures and indications for all corneal transplants performed at the University of Toronto. DesignRetrospective cross-sectional study. ParticipantsOne thousand one hundred and four consecutive corneal transplants performed at the Kensington Eye Institute (KEI). MethodsDemographic, clinical, and pathological data retrieved from the Ophthalmic Pathology Laboratory on all corneal transplants performed at the KEI from January 2014 to December 2016. ResultsOver 3 years, partial-thickness lamellar keratoplasties were performed in 880 cases (80%) while full-thickness penetrating keratoplasties (PKP) accounted for 224 cases (20%). Leading causes of corneal transplant were Fuchs’ dystrophy (42%), graft failure (17%), bullous keratopathy (15%), and keratoconus (15%). Graft failure (40%) and keratoconus (31%) were the leading causes for PKP. Descemet’s membrane endothelial keratoplasty (DMEK) accounted for 37% of cases, Descemet’s stripping automated endothelial keratoplasty (DSAEK) for 30%, and deep anterior lamellar keratoplasty (DALK) for 13%. By 2016, partial-thickness procedures had increased by 10%, accounting for 85% of all procedures. In addition, DMEK increased by 26%, DSAEK decreased by 13%, and PKP decreased by 11%. Fuchs’ dystrophy remained the leading indication for DMEK (67%) and DSAEK (42%) procedures. In 2016, 73% of DALK procedures were for the treatment of keratoconus. ConclusionsPartial-thickness corneal transplants now account for 85% of all current graft procedures, and DMEK has emerged as the procedure of choice. Graft failure continues to be the leading indication for full-thickness grafts. Longitudinal studies are needed to determine whether these new trends persist and their future impact on graft failures.

Current indications and surgical approaches to corneal transplants at the University of Toronto: A clinical-pathological study

ObjectiveTo determine the most common reasons and surgical approaches for corneal graft surgery at the Kensington Eye Institute (KEI), University of Toronto. DesignRetrospective cross-sectional study. ParticipantsA total of 229 consecutive corneal transplants performed at the KEI. MethodsDemographic, clinical, and pathological data on all 2012 and 2013 corneal transplants were collected. ResultsThe mean age for corneal transplants was 65 ± 16 years; 39% were full-thickness penetrating keratoplasties (PK) and 61% were partial-thickness. Graft failure (30%), infection (18%), and keratoconus (17%) were the leading indications for PK. Fuchs’ dystrophy (40%) and bullous keratopathy (24%) were main causes for partial-thickness procedures. Among partial-thickness approaches, Descemet’s stripping automated endothelial keratoplasty (DSAEK), deep anterior lamellar keratoplasty (DALK), and Descemet’s membrane endothelial keratoplasty (DMEK) procedures accounted for 68%, 16%, and 16%, respectively. Fuchs’ dystrophy (40%) and bullous keratopathy (33%) were the most common indications for DSAEK. Keratoconus (57%) and corneal scarring (35%) were the most common indications for DALK, whereas Fuchs’ dystrophy (82%) accounted for most DMEK procedures. The most common reasons for all corneal grafts were Fuchs’ dystrophy (25%), bullous keratopathy (21%), graft failure (17%), and keratoconus (12%). ConclusionsAlmost two-thirds of all corneal transplant procedures at the University of Toronto are partial thickness procedures. A failed graft was found to be the most common indication for full-thickness transplants. Fuchs’ dystrophy was the most common indication for a partial-thickness approach, most often treated by DSAEK. Longitudinal data are needed to determine whether partial-thickness surgeries will improve graft survival and reduce the need for regraft.

Corneal grafting for the treatment of full-thickness corneal defects in dogs: a review of 50 cases.

To describe corneal grafting for the treatment of full-thickness corneal defects in dogs and to determine its effectiveness in preserving vision. A review of the medical records of dogs that underwent corneal grafting following corneal perforations (≥3 mm) at the VTH-UAB from 2002 to 2012 was carried out. Fifty dogs of different breed, age and gender were included. Brachycephalic breeds were overrepresented (37/50;74%). All cases were unilateral, with euryblepharon being the most common concurrent ocular abnormality (20/50;40%). Full-thickness penetrating keratoplasties (FTPK) were performed in 21/50 eyes (42%) and lamellar keratoplasties (LK) in 29/50 eyes (58%). Frozen grafts (FroG) were used in 43/50 eyes (86%) and fresh homologous grafts (FreHoG) in 7/50 (14%). Of the former group, 26 were homologous (FroHoG:60%) and 17 heterologous (FroHeG:40%). A combination of topical medication (antibiotics, corticosteroids, cycloplegics, and 0.2% cyclosporine A) and systemic mycophenolate mofetil was administered. Median follow-up time was 200 days. Postsurgical complications included wound dehiscence (6/50;12%) and glaucoma (4/50;8%). Clinical signs of graft rejection were diagnosed as follows: FroHoG (13/26;50%), FroHeG (11/17;65%), FreHoG (4/7;57%), FTPK (12/21;57%), and LK (16/29;55%). Medical treatment successfully controlled graft rejection in 11/28 eyes (39%). Good anatomical outcome was achieved in 86% (43/50), of which 95% (41/43) were visual at last examination, with moderate opacification to complete transparency of the graft present in 48.2%. Corneal grafting is an effective surgical treatment for full-thickness corneal defects in dogs. If graft rejection is present, additional medical or surgical therapy may be necessary, achieving a highly satisfactory visual outcome.