Deep anterior lamellar keratoplasty and penetrating keratoplasty in macular corneal dystrophy: comparison of visual and topographic outcomes and complications.

PURPOSES: This study aims to assess and compare the postoperative visual and topographic outcomes, complications, and graft survival rates following deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with macular corneal dystrophy. METHODS: In this study we enrolled 59 patients (23 male; and 36 female) with macular corneal dystrophy comprising 81 eyes. Out of these, 64 eyes underwent penetrating keratoplasty, while 17 eyes underwent deep anterior lamellar keratoplasty. The two groups were analyzed and compared based on best-corrected visual acuity, corneal tomography parameters, pachymetry, complication rates, and graft survival rates. RESULTS: After 12 months, 70.6% of the patients who underwent deep anterior lamellar keratoplasty (DALK) and 75% of those who had penetrating keratoplasty (PK) achieved a best-corrected visual acuity of 20/40 or better (p=0.712). Following surgery, DALK group showed lower front Kmean (p=0.037), and Q values (p<0.01) compared to the PK group. Postoperative interface opacity was observed in seven eyes (41.2%) in the DALK group. Other topography values and other complications (graft rejection, graft failure, cataract, glaucoma, microbial keratitis, optic atrophy) did not show significant differences between the two groups. The need for regrafting was 9.4% and 11.8% in the PK and DALK groups, respectively (p=0.769). Graft survival rates were 87.5% and 88.2% for PK and DALK; respectively (p=0.88 by Log-rank test). CONCLUSION: Both PK and DALK are equally effective in treating macular corneal dystrophy, showing similar visual, topographic, and survival outcomes. Although interface opacity occurs more frequently after DALK the visual results were comparable in both groups. Therefore, DALK emerges as a viable surgical choice for patients with macular corneal dystrophy without Descemet membrane involvement is absent.

Long-Term Follow-Up of Pediatric Excimer Laser-Assisted Penetrating Keratoplasty for Congenital Stromal Corneal Dystrophy.

PURPOSE: The purpose of this study was to highlight characteristic clinical and microscopic findings and report the long-term follow-up of pediatric excimer laser-assisted penetrating keratoplasty (excimer-PKP) for congenital stromal corneal dystrophy (CSCD). METHODS: A 2-year-old Greek child presented with CSCD at our department. Clinical examination showed bilateral flake-like whitish corneal opacities affecting the entire corneal stroma up to the limbus. Genetic testing identified a mutation of the decorin gene (c.962delA). The variant was not present in the parents and represented a de novo mutation. The uncorrected visual acuity was 20/100 in both eyes. Excimer-PKP (8.0/8.1 mm) was performed on the right eye at the age of 2.5 years and on the left eye at the age of 3 years. Postoperatively, alternating occlusion treatment was performed. RESULTS: The light microscopic examination demonstrated a disorganized extracellular matrix of the corneal stroma characterized by a prominent irregular arrangement of stromal collagen lamellae with large interlamellar clefts containing ground substance, highlighted by periodic acid-Schiff- and Alcian blue-positive reaction detecting acid mucopolysaccharides. Electron microscopy showed disorganization and caliber variation of collagen lamellae and thin filaments within an electron-lucent ground substance. The postoperative course was unremarkable. Both grafts remained completely clear 14 years postoperatively. Corneal tomography showed moderate regular astigmatism with normal corneal thickness. The corrected distance visual acuity was 20/25 in both eyes. CONCLUSIONS: Excimer-PKP for CSCD might be associated with excellent long-term results and a good prognosis, particularly when the primary surgery is performed at a very young age. However, this requires close postoperative follow-up examinations by an experienced pediatric ophthalmologist to avoid severe amblyopia.

Familial primary calcific band-shaped keratopathy with late onset systemic disease: a case series and review of the literature.

BACKGROUND: Familial calcific band-shaped keratopathy (BSK) is a very rare disease, with no underlying cause. There is no underlying disease in this form of the disease. This article introduces a family with seven children, three of whom were diagnosed with familial primary calcific BSK. One of them developed a systemic disease 38 years after ocular manifestation. CASE PRESENTATION: In this case report, three Iranian siblings from a family with familial calcific band-shaped keratopathy (BSK) are introduced. Systemic and ocular examinations performed on these patients indicated the occurrence of chronic kidney disease in the older child, a 41-year-old woman, 38 years after ocular manifestation. The examinations conducted on the other two siblings revealed no pathological findings. The 41-year-old sister and 37-year-old brother underwent unilateral deep anterior lamellar keratoplasty (DALK), while the 33-year-old sister underwent bilateral superficial keratectomy (SK). CONCLUSION: Considering the late onset of systemic disease in one of the siblings diagnosed with familial calcific band-shaped keratopathy (BSK), it is crucial to emphasize the necessity of long-term follow-up for these patients and their families.

Clinical outcomes of epithelial basement membrane dystrophy after keratorefractive lenticule extraction.

PURPOSE: To determine the clinical outcomes of keratorefractive lenticule extraction (KLEx) in eyes with epithelial basement membrane dystrophy (EBMD) that developed after surgery. SETTING: Onnuri Smile Eye Clinic, Seoul, South Korea. DESIGN: Retrospective single-center study. METHODS: This study reviewed the medical records of 26 eyes of 16 patients who exhibited signs of EBMD after KLEx. Postoperatively, corneal findings and visual outcomes were evaluated. Statistical analyses were also performed on eyes without corneal complications after KLEx. RESULTS: Signs of EBMD were first observed within 1 week postoperatively in 22 eyes (84.6%): 6 eyes (23.1%) showed epithelial defects, 10 eyes (38.5%) showed subepithelial corneal opacity, 5 eyes (19.2%) showed diffuse lamellar keratitis, and 1 eye (3.9%) showed epithelial ingrowth. Symptoms such as pain, while corneal lesions were present, occurred in 21 eyes (80.8%). At 3 months postoperatively, 21 eyes (80.8%) showed no specific findings on slitlamp microscopy after medical treatment, 2 eyes (7.7%) showed subepithelial corneal opacity, 2 eyes (7.7%) showed corneal scar, and 1 eye (3.9%) showed epithelial ingrowth. Uncorrected distance visual acuity was 20/25 or better in 24 eyes (92.3%), and spherical equivalent was within ±1.0 D in 20 eyes (76.9%). The efficacy index of the EBMD group did not significantly differ from the control group, while the safety index was significantly lower. CONCLUSIONS: Manifestations of EBMD can occur after KLEx and can affect clinical outcomes. Most cases showed favorable results with appropriate nonsurgical treatment; however, some cases had long-term complications such as corneal scarring.

Novel Manifestation of Corneal Dystrophy After Keratorefractive Surgery.

PURPOSE: This study aimed to report cases of bilateral corneal Bowman layer deposits in 4 patients with a history of keratorefractive surgery. To our knowledge, this condition has not previously been reported and should be distinguished from granular corneal dystrophy type 2 and other corneal dystrophies. METHODS: We reviewed all available medical records that were collected between January 2010 and December 2021 at a tertiary referral center and performed whole-exome sequencing to provide diagnostic information. RESULTS: Four patients exhibited similar bilateral corneal deposits that were observed more than 10 years after keratorefractive surgery. The patients' ages ranged from 36 to 53 years; 3 of the 4 patients were female. Three patients received laser in situ keratomileusis surgery, and 1 received radial keratotomy. All 4 patients denied having a family history of ocular diseases and reported an uneventful postoperative course. On examination, the best-corrected visual acuity ranged from 6/10 to 6/6 in all 4 patients. Slit-lamp examination revealed bilateral superficial corneal deposits involving the central cornea, and anterior segment optical coherence tomography revealed hyperreflective deposits located in the Bowman layer. Such unique manifestations suggested corneal dystrophy; thus, whole-exome sequencing was performed on all 4 patients. Only 1 patient exhibited a missense mutation in TGFBI . We further analyzed common de novo mutations to explore possible candidate genes associated with this presentation. CONCLUSIONS: We report a rare entity of presumed corneal dystrophy with deposits located in the Bowman layer in 4 patients who had received keratorefractive surgery. Clarifying the underlying pathophysiology and genetic predisposition of this disease may aid in diagnosing and preventing potential complications after keratorefractive surgery.

12-year follow-up of the first endothelial keratoplasty without Descemet stripping in a 3-month newborn with Congenital Hereditary Endothelial Dystrophy (CHED).

BACKGROUND: Endothelial Keratoplasty (EK) is now considered as the standard treatment for Congenital Hereditary Endothelial Dystrophy (CHED) by many surgeons. We present the 12-year clinical outcome of the youngest operated patient with CHED in which we successfully performed a bilateral EK procedure without removing the recipient endothelium-Descemet complex. CASE PRESENTATION: In November 2010 we performed EK without Descemet Stripping in a 3-month female newborn, thinking that the lower manipulation obtained by leaving the recipient endothelium-Descemet complex could be the key factor for the success of our surgery. Such a particular technique was new in newborns. The surgery was a success, but the long-term visual result was not predictable at that time. We followed the patient at 4 months, and then yearly. At the latest visit in October 2022 the visual, cognitive, and motorial developments were normal, with Best-corrected Distance Visual Acuity of 0.4 LogMAR with - 0.75 D sf + 2.75 D cyl @ 105° in the right eye (RE) and 0.4 LogMAR with + 1.50 D sf + 2.50 D cyl @ 60° in the left eye (LE). The endothelial microscope showed an unexpected healthy endothelium, with a cell count of 2383 cells/mm2 in the RE and of 2547 cells/mm2 in the LE from a starting donor count of 2900 cells/mm2. No secondary procedures were performed during the 12-year follow-up. CONCLUSION: EK without Descemet stripping has proved to be a successful procedure over time in our newborn. The unexpected healthy endothelium suggests a role of the Descemet membrane in CHED.

Sequential Custom Therapeutic Keratectomy for the Treatment of Granular Corneal Dystrophy Type 1: A Long-term Study.

PURPOSE: To evaluate the effectiveness of sequential custom phototherapeutic keratectomy (SCTK) for granular corneal dystrophy type 1 (GCD1). METHODS: Thirty-seven eyes of 21 patients with GCD1 were treated with SCTK to remove superficial opacifications, regularize the corneal surface, and decrease optical aberrations. SCTK is a sequence of custom therapeutic excimer laser keratectomies with step-by-step intraoperative corneal topography monitoring of results. Six eyes of 5 patients previously treated with penetrating keratoplasty received SCTK for disease recurrence. Pre-operative and postoperative corrected distance visual acuity (CDVA), refractive values, mean pupillary keratometry, and pachymetry were retrospectively analyzed. The mean follow-up period was 41.3 months. RESULTS: SCTK provided significant decimal CDVA improvement, from 0.33 ± 0.22 to 0.63 ± 0.24 (P < .0001) at the last available follow-up visit. One eye, initially treated with penetrating keratoplasty, showed visually significant disease 8 years after the first SCTK and was re-treated. Mean corneal pachymetry difference between preoperative and final follow-up values was 78.42 ± 62.26 µm. Mean corneal curvature and the spherical component did not show a statistically significant change or hyperopic shift. Astigmatism and higher order aberration reduction were statistically significant. CONCLUSIONS: SCTK is a powerful tool for the treatment of anterior corneal pathologies hindering vision and quality of life, such as GCD1. SCTK is less invasive and fosters more rapid visual recovery than penetrating keratoplasty or deep anterior lamellar keratoplasty. Providing significant visual improvement, SCTK can be the preferred initial treatment in eyes with GCD1. [J Refract Surg. 2023;39(6):422-429.].

Repeat deep anterior lamellar keratoplasty (DALK) for failed primary DALK.

Purpose: To evaluate the effectiveness of repeat deep anterior lamellar keratoplasty (DALK) in patients of previous failed DALK. Methods: : A retrospective analysis of records of seven patients who had undergone repeat DALK following the failure of the primary DALK was done. The indications for repeat surgery, time elapsed since the first surgery, and pre- & postoperative best-corrected visual acuity (BCVA) were noted for all the patients. Results: The follow-up period ranged between one- to four-year post repeat DALK. The indication of primary DALK was keratoconus with vernal keratoconjunctivitis (VKC) (n = 3), corneal amyloidosis (n = 2), Salzman nodular keratopathy (n = 1), and healed keratitis (n = 1). The need for repeat surgery arose when the BSCVA dropped to less than 20/200. The time interval elapsed since the first surgery ranged from two months to four years. Postoperatively, the BSCVA improved from 20/120 to 20/30 at the end of one-year post repeat DALK in all except one patient. All regrafts were clear at the most recent examination, performed after a mean period of 18 months after the secondary graft. No complication was encountered during the resurgery. The dissection of the host bed was easier in the second surgery owing to weaker adhesions. Conclusion: The prognosis for repeat DALK for failed DALK is excellent, and the outcomes of secondary grafts were comparable to those of primary DALK grafts. Re DALK offers the advantage of an easier dissection and lower chances of graft rejection compared to penetrating keratoplasty.

Etiology-Specific Comparison of the Long-Term Clinical Outcome of Repeat Deep Anterior Lamellar Keratoplasty for Optical Indications.

PURPOSE: The aim of this study was to evaluate the etiology-specific clinical outcomes and complications of repeat deep anterior lamellar keratoplasty (DALK) after failed DALK. METHODS: This retrospective case study included 32 eyes of 27 patients who underwent repeat DALK of 450 cases of DALK performed for optical indications between 1997 and 2013. The patients were divided into 4 etiology-specific subgroups (the corneal dystrophy, ocular surface disease, stromal scar, and others) or those with or without limbal stem cell deficiency (LSCD). The clinical outcomes evaluated were graft survival, best-corrected visual acuity, endothelial cell density, and complications. RESULTS: The mean postoperative follow-up duration was 69.6 ± 54.8 months. The 1-, 3-, and 5-year overall graft survival rate were 76.7%, 57.5%, and 38.8% respectively. The graft survival rate was the highest in the corneal dystrophy group ( P = 0.0014) and was significantly ( P = 0.0010) higher in eyes without LSCD than in eyes with LSCD. There were no significant differences in the graft survival rates between the previous and current DALK groups. The postoperative best-corrected visual acuity of all subjects improved significantly. The postoperative endothelial cell density did not decrease after repeat DALK. There were no significant differences in the incidence of complications between patients with and without LSCD, except the incidence of persistent epithelial defects. CONCLUSIONS: Repeat DALK had favorable outcomes in all etiology-specific groups, whereas eyes with LSCD required careful assessment of the ocular surface to avoid graft failure due to persistent epithelial defects.

Paraproteinemic Keratopathy in a Patient With Previous LASIK Procedure Mimicking Lattice Corneal Dystrophy.

PURPOSE: The aim of this study was to report a unique clinical presentation of paraproteinemic keratopathy after a myopic uneventful laser in situ keratomileusis (LASIK) procedure that led to the diagnosis of gammopathy of undetermined significance. METHODS: This was an interventional case report. A 55-year-old woman present with bilateral branching opacities limited to the optical zone of myopic LASIK. The patient's medical history was unremarkable. RESULTS: After ruling out a mutation in TGF-ß1 , a systemic workup was performed, revealing an IgG level of 12.8 mg/dL, lambda-free light chain of 12.8 mg/dL, and M-spike of 0.6 g/dL. Bone marrow aspiration was slightly hypercellular, without evidence of neoplastic infiltration by plasma cells. The patient underwent 3 cycles of systemic chemotherapy, with improvement in best-corrected visual acuity. CONCLUSIONS: Paraproteinemic keratopathy is a rare clinical presentation that may lead to a systemic diagnosis of hematologic malignancy. To the best of our knowledge, this is the first reported case of paraproteinemic keratopathy after LASIK.

Clinical and Histopathologic Characteristics and Template of the TGFBI p.(His626Arg) Missense Variant Lattice Corneal Dystrophy.

PURPOSE: The aim of this study was to define, following the IC3D template format, the clinical and histopathologic phenotype of the p.(His626Arg) missense variant lattice corneal dystrophy (LCDV-H626R), the most common variant lattice dystrophy, and to record long-term outcome of corneal transplantation in this dystrophy. METHODS: A database search and a meta-analysis of published data on LCDV-H626R were conducted. A patient diagnosed with LCDV-H626R who underwent bilateral lamellar keratoplasty followed by rekeratoplasty of 1 eye is described, including histopathologic examination of the 3 keratoplasty specimens. RESULTS: One hundred forty-five patients from at least 61 families and 11 countries diagnosed with LCDV-H626R were found. This dystrophy is characterized by recurrent erosions, asymmetric progression, and thick lattice lines that extend to corneal periphery. The median age is 37 (range, 25-59) years at the onset of symptoms, 45 (range, 26-62) years at the time of diagnosis, and 50 (range, 41-78) years at the time of the first keratoplasty, suggesting a median interval from the first symptoms to diagnosis and to keratoplasty of 7 and 12 years, respectively. Clinically unaffected carriers have been of age 6 to 45 years. Central anterior stromal haze and centrally thick, peripherally thinner branching lattice lines in the anterior to midstroma of the cornea were noted preoperatively. Histopathology of the host anterior corneal lamella showed a subepithelial fibrous pannus, a destroyed Bowman layer, and amyloid deposits extending to the deep stroma. In the rekeratoplasty specimen, amyloid localized to scarring along the Bowman membrane and to the margins of the graft. CONCLUSIONS: The IC3D-type template for LCDV-H626R should help diagnose and manage variant carriers. The histopathologic spectrum of findings is broader and more nuanced than what has been reported.

Corneal Electrolysis for Granular Corneal Dystrophy Type 2 (Avellino Corneal Dystrophy) Exacerbation After LASIK.

PURPOSE: To report two cases in which exacerbation of granular corneal dystrophy type 2 (GCD2; Avellino corneal dystrophy) after laser in situ keratomileusis (LASIK) was successfully removed by corneal electrolysis. METHODS: This study involved a 66-year-old man and a 43-year-old man with GCD2 who had undergone bilateral LASIK for myopia 10 or more years prior to presentation. In both patients, GCD2 corneal opacity gradually developed postoperatively at the LASIK flap interface, thus resulting in a decrease of visual acuity. For treatment, the LASIK flaps in both patients were surgically lifted to directly remove the opacity. Corneal electrolysis was then applied to the back of each LASIK flap and stromal bed. RESULTS: Postoperatively, the ocular symptoms and corneal opacities related to GCD exacerbation disappeared, with improvement of corrected and uncorrected distance visual acuity and almost no change of refractive error. CONCLUSIONS: The findings reveal that corneal electrolysis is safe and effective for treating exacerbations of GCD2 following LASIK when applied to a surgically lifted flap, and that it successfully removes GCD2-related LASIK flap interface opacities with almost no change of refractive error postoperatively. [J Refract Surg. 2023;39(1):61-65.].

Phototherapeutic keratectomy versus epithelial debridement combined with anterior stromal puncture or diamond burr for recurrent corneal erosions.

OBJECTIVE: To compare outcomes of phototherapeutic keratectomy (PTK) versus epithelial debridement combined with anterior stromal puncture (ASP) or diamond burr for the treatment of recurrent corneal erosions (RCES) in a large tertiary centre. METHODS: Patients with a diagnosis of RCES secondary to trauma or epithelial basement membrane dystrophy who underwent a surgical procedure between 2009 and 2019 were included in the study. The following data were collected: demographics, ocular history, prior medical treatment, ocular surgeries, intervention, complete epithelialization at postoperative week 1, recurrences, and complications. Recurrence was defined as either an objective finding of a corneal epithelial defect or symptoms suggestive of recurrent epithelial erosion on history. Recurrence rate and time to epithelialization were compared between groups. RESULTS: A total of 97 eyes (73 patients) were included in the study. Mean patient age was 51 ± 16.1 years, and mean follow-up was 474 days. RCES was secondary to epithelial basement membrane dystrophy in 80% (n = 78 of 97), trauma (15%, n = 15 of 97), or idiopathic (4%, n = 4 of 97). Epithelial debridement with ASP was performed in 34 eyes (35%), diamond burr in 33 eyes (33%), and PTK in 30 eyes (31%). Compared with epithelial debridement with ASP (recurrence 29.4%), the recurrence rate was significantly lower for both the diamond burr (9.1%, p = 0.031) and PTK groups (10%, p = 0.048). The diamond burr and PTK groups also had a significantly higher rate of complete epithelialization at 1 week (p < 0.05). CONCLUSION: Compared with epithelial debridement with ASP, diamond burr and PTK have significantly lower rates of recurrence and time to epithelialization and may be considered first for surgical management of RCES.

Complications in deep anterior lamellar keratoplasty - A retrospective interventional analysis in a large series.

Purpose: To analyze the complications in patients managed with deep anterior lamellar keratoplasty (DALK) for diseases of the anterior corneal stroma. Methods: This is a retrospective analysis of all the patients who underwent DALK in a tertiary care center in South India from 2010 to 2020. A total of 474 eyes in 373 patients were included in the study. Patients who underwent DALK for advanced keratoconus, keratoconus with Bowman's membrane scar, healed hydrops, macular corneal opacity, macular corneal dystrophy, granular corneal dystrophy, spheroidal degeneration, pellucid marginal degeneration, post-laser-assisted in situ keratomileusis ectasia, descematocele, post-collagen cross-linking aborted melt and dense scar, and post-radial keratotomy were included in the study. The patients were followed up for 17.2 +/- 9.2 months (1-9 years). Results: Complications noted in the surgery were intra-operatively Descemet's membrane perforation in 31 eyes (6.54%), post-operatively secondary glaucoma in 16 eyes (3.37%), cataract in seven eyes (1.47%), suture-related complications in five eyes (1.05%), graft rejection in three eyes (0.63%), traumatic dehiscence in two eyes (0.42%), filamentary keratitis in two eyes (0.42%), interface infiltrate in one eye (0.21%), and recurrence of disease in four eyes (7.14%) out of 57 eyes with corneal dystrophy. Conclusion: DALK as an alternative to penetrating keratoplasty for anterior corneal stromal diseases. It has become an automatic choice for diseases of the anterior cornea requiring keratoplasty. Complications can occur at any stage of surgery; however, if identified and managed early, they can result in optimal outcome.

[The effect of silicone oil retention sutures on preventing silicone oil migration and protecting the corneal endothelium].

Objective: To observe the restriction effect of silicone oil retention sutures and their protective effect on the corneal endothelium. Methods: Retrospective case series study. The clinical data of 6 patients (6 eyes) with lens-iris damage after severe ocular trauma were collected from March 2017 to November 2021 in Beijing Tongren Hospital. Their was combined retinal injury in each eye, so silicone oil retention sutures and silicone oil filling were performed. The silicone oil position was observed by slit lamp and ultrasound biomicroscopy. The corneal endothelium was examined by specular microscopy during the follow-up. Results: All patients were male, with an average age of 47 years (range, 26 to 73 years). The diseased eyes included 2 left eyes and 4 right eyes. Five eyes had ocular rupture, and 1 eye had ocular contusion. The follow-up time ranged from 5 months to 51 months, with an average of 18.5 months. In all 6 eyes, the silicone oil was completely located in the posterior segment and never touched the corneal endothelium. Four eyes maintained healthy and had a clear cornea during the follow-up, while 2 eyes developed band keratopathy at the 11 month and 16 month separately during follow-up, 1 of which was found to suffer corneal decompensation at the last follow-up (51 month). Both band keratopathy and corneal decompensation were caused by severe anterior segment trauma and were not related to the silicone oil contact with the cornea. There were no complaints about occlusion or glare due to silicone oil retention sutures. All patients did not need to keep the prone position postoperatively. Silicone oil emulsification occurred in 1 eye and ocular hypertension occurred in this eye after silicone oil emulsification. Conclusion: Silicone oil retention sutures can effectively prevent silicone oil from migrating to the anterior chamber or contacting the corneal endothelium.

Penetrating Keratoplasty Versus Descemet Stripping Automated Endothelial Keratoplasty in Children With Congenital Hereditary Endothelial Dystrophy: Long-Term Results.

PURPOSE: The purpose of this study was to compare the outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PKP) in patients with congenital hereditary endothelial dystrophy (CHED). METHODS: This was a retrospective, comparative study of all the patients with a histopathological diagnosis of CHED who underwent PKP or DSAEK between January 1, 1990, and December 31, 2016. All the cases were included except those patients who had clear grafts but did not complete 2 years of postoperative follow-up. The main outcome measure was graft clarity 2 years after surgery. RESULTS: There were 111 eyes of 63 patients. Seventy-six eyes underwent PKP, and 35 eyes underwent DSAEK. The median age at surgery was 6.8 years in the PKP group and 10.32 years in the DSAEK group. At 2 years postoperatively, clear grafts were noted in 66 of 76 (86.8%) eyes in the PKP group and 30 of 35 (85.7%) eyes in the DSAEK group. At the last follow-up, 80.3% of PKP grafts and 82.8% of DSAEK grafts were clear ( P =0.5). The type and timing of complications differed between the 2 groups. The PKP group had a statistically significant higher rate of graft rejection (19.5%) versus the DSAEK group (0%) ( P =0.01). DSAEK complications were mainly lenticule detachment that developed within one month postoperatively. There was no statistically significant difference in the visual outcomes at the last follow-up between the groups. CONCLUSION: Endothelial keratoplasty is a safe alternative to conventional PKP in CHED. The visual outcome and survival rates were comparable, but DSAEK had a lower rejection rate and fewer suture-related complications.

Early onset unilateral Terrien's marginal degeneration.

A young man in his first decade of life presented with insidious onset, gradually progressive diminution of vision in right eye since 2 months associated with foreign body sensation. Slit-lamp examination revealed superior arcuate band of corneal stromal thinning extending from 9-3 o' clock. There was associated corneal vascularisation and presence of lipid deposition at the leading edge of the furrow formation with intact epithelium without any apparent signs of inflammation. There was no previous history of ocular or systemic disease, trauma, ocular surgery, collagen vascular disease or contact lens wear. Serological tests for rheumatic diseases did not show any abnormalities. Scheimpflug imaging showed high against the rule astigmatism with a 'reverse crab claw' pattern. A provisional diagnosis of right eye Terrien's marginal corneal degeneration was made. On a 1-month follow-up visit, there was significant symptomatic relief with lubricants alone and with spectacles the visual acuity improved to 20/60 in the right eye.

Histological findings of corneal tissue after failed phototherapeutic keratectomy in macular corneal dystrophy - a case report.

BACKGROUND: Macular corneal dystrophy is a rare inherited disease of the cornea leading to deposits mainly in the stroma. Affected patients suffer from progressive loss of visual acuity which should be treated with penetrating keratoplasty. This is the first case report describing the clinical and histopathological findings of corneal tissue after failed phototherapeutic keratectomy (PTK) in a patient with macular corneal dystrophy. CASE PRESENTATION: A 32-year-old man presented with visual impairment, blurred vision and increasing glare sensitivity in both eyes in 2014. All symptoms had existed for several years and had recently increased sharply. A corneal dystrophy was diagnosed and penetrating keratoplasty was recommended but the patient was hesitant to undergo surgery. In 2018, in contrast to current guidelines, a PTK was performed in both eyes in Turkey for unknown reasons. In May 2019, he presented again in our clinic. Best corrected visual acuity was markedly reduced in both eyes. Slit-lamp examination revealed multiple dense, poorly circumscribed grey-white patchy changes in the stroma accompanied by corneal opacity in both eyes. In February 2020, the patient decided to have penetrating keratoplasty performed at the University Eye Hospital in Tübingen. The explanted cornea was stained for acid mucopolysaccharides (AMP) and periodic acid-Schiff staining (PAS). The histopathological examination revealed destruction of Bowman's layer and a subepithelial fibrosis band due to the PTK previously performed. The AMP staining demonstrated blue deposits typical of macular corneal dystrophy, mainly in the stroma but also in the endothelium. Interestingly, the acidic mucopolysaccharides were found increased in the PTK-induced subepithelial fibrosis band. The postoperative course after keratoplasty was favourable with a significant increase in visual acuity and a clear graft. CONCLUSIONS: This report presents the first case of a histologically evident exacerbation of macular corneal dystrophy after PTK and emphasizes the relevance of thorough pre-interventional diagnosis and patient selection to consider other therapeutic approaches, such as penetrating keratoplasty.

Influence of graft vascularization on graft survival following homologous limbo-keratoplasty.

PURPOSE: Limbo-keratoplasty enables visual improvement and limbal stem cell transplantation at the same. During follow-up, most grafts show vascularization of the limbus. However, it is unclear whether vascularization is harmful due to immunologic effects or helpful to nourish the limbal stem cells and is therefore necessary for a clear graft. The aim of our study is to analyze the influence of graft vascularization on graft survival following homologous limbo-keratoplasty. METHODS: In this retrospective study, we assessed all consecutive limbo-keratoplasties performed in our hospital. All eyes with suitable photo-documentation were included and divided into two groups (limbal stem cell deficiency and corneal dystrophy). We categorized the grade of vascularization (0, 1, 2, 3, 3b) and analyzed clear graft survival, recurrence of the underlying disease and the endothelial cell density (ECD) with regard to the reason for the graft. Event rates were estimated with the Kaplan-Meier method. RESULTS: A total of 79 eyes with limbal stem cell deficiency and 15 with corneal dystrophies were analyzed. A high degree of graft vascularization had a tendency for better graft survival in limbal stem cell deficiency, whereas in corneal dystrophies, grafts with no vascularization had preferable outcomes. Recurrence-free graft survival was only seen in grade 1 and 3 vascularization in corneal dystrophies. CONCLUSION: Vascularization of the limbus seems to have an impact on the long-term outcome of limbo-keratoplasty. The effect seems to be favorable in limbal stem cell deficiency and on recurrence rates in corneal dystrophies. However, the latter might be overshadowed by an unfavorable immunologic effect in corneal dystrophies where the baseline immunologic risk profile is commonly more favorable than in limbal stem cell deficiency.

Transepithelial phototherapeutic keratectomy for post-traumatic recurrent corneal erosions.

Purpose: To evaluate the outcomes of transepithelial phototherapeutic keratectomy (transepithelial PTK) for treatment of posttraumatic recurrent corneal erosions. Methods: Twenty-four eyes of 22 patients with posttraumatic recurrent corneal erosions who were treated with transepithelial PTK from April 2018 to July 2020 were included in this retrospective study. The rates of recurrent erosions and complications were evaluated during the follow-up after surgery. Visual acuity and refraction were recorded preoperatively and 1 year after surgery. Total corneal astigmatism, total corneal irregular astigmatism, and total corneal spherical aberrations were recorded using corneal tomography preoperatively and 1 year after surgery. Results: Mean postoperative follow-up was 13 months (range: 12-32 months). None of the patients suffered from any complications or further erosions. Uncorrected distance visual acuity, best-corrected distance visual acuity, spherical equivalent, and cylinder remained stable at 1-year postoperatively compared with the baseline (P = 0.214, P = 0.461, P = 0.084, and P = 0.879, respectively). Moreover, there was no significant difference in total corneal astigmatism, total corneal irregular astigmatism, and total corneal spherical aberrations between baseline and 1-year postoperative visit (P = 0.938, P = 0.136, and P = 0.981, respectively). Conclusion: Transepithelial PTK was an effective treatment for patients with posttraumatic recurrent corneal erosions.