Clinical outcomes in post-epikeratophakic eyes after removal of epikeratoplasty lenticule.

BACKGROUND: Assessment of the optical outcome and adverse events in post-epikeratopathic eyes after removal of the epikeratoplasty lenticule (EKPL). METHODS: This was a retrospective case-series study of patients who underwent EKPL removal between 2002 and 2020. Ten eyes were included in the analysis. We compared the clinical characteristics of the patients before surgery, 6 months after surgery, before lenticular removal, and after removal, and reported optical or ocular surface complications. RESULTS: We removed EKPL due to the lenticular opacity in five eyes (50%), intraocular lens (IOL) insertion (n = 4, 40%) after cataract surgery (n = 3) or in aphakic eyes (n = 1), and lenticule-induced irregular astigmatism in one eye (10%). After EKPL removal, the mean refractive power of the cornea (Km) revealed a tendency to increase. Out of nine cases, six cases showed corneal steepening and three cases revealed corneal flattening. When the keratometric readings of pre-epikeratoplasty and post-lenticular removal were compared within the same case, the average difference was 5.1 D ± 4.0 (n = 8). Complications were observed in 3 of 10 cases (excessive corneal flatness, ectatic change, and abnormal epithelial cell ingrowth) after removal. CONCLUSIONS: The surgeon should expect the corneal refractive power to steepen or flatten in some cases with abnormal astigmatism and irregularity. Epikeratophakic eyes may exhibit serious ectatic changes, and abnormal epithelial cell ingrowth after removal of epikeratophakic lenticules.

Long-term viability of allogenic donor stroma.

We report the clinical history and histopathology of the longest known postoperative course of a myopic cornea lenticule implanted via epikeratoplasty that also had been subjected to excimer laser and mitomycin. Despite the mechanical and photochemical processes the allogenic cornea stroma had sustained, it is notable that it retained structural integrity and clarity. This report affirms the potential long-term clarity and resilience of allogenic stromal cornea and supports its use as a potential stabilizing option in cornea allogenic intrastromal ring segments for keratoconus and variations thereof for other cornea disorders.

Epikeratophakia using small-incision lenticule extraction lenticule addition combined with corneal crosslinking for keratoconus.

An 18-year-old man with keratoconus had epikeratophakia using small-incision lenticule extraction lenticule addition in the left eye, which had a minimum corneal thickness of 356 µm. Accelerated (45 mW/cm2) transepithelial corneal crosslinking was performed 1 month later. The patient was followed for 3 years postoperatively. Examinations included anterior segment optical coherence tomography (AS-OCT), uncorrected (UDVA) and corrected (CDVA) distance visual acuities, subjective refraction, and topographic changes. The UDVA in the left eye improved from 20/200 preoperatively to 20/63 postoperatively, and the CDVA improved from 20/125 to 20/40. The manifest refraction was -1.50 -5.25 × 110. Corneal topography showed that lenticule implantation increased the thickness of the central and midperipheral cornea, with a minimum corneal thickness of 470 µm. The mean keratometry and greatest posterior elevation values were stable from 3 months postoperatively forward. On AS-OCT, the lenticule remained transparent and was attached smoothly with a visible demarcation line.

Tectonic epikeratoplasty with ethanol-stored donor corneas.

To evaluate the efficacy and outcomes of tectonic epikeratoplasty with use of ethanol-preserved corneal grafts for the management of perforated corneal melts. The present retrospective case series includes 10 eyes which underwent tectonic epikeratoplasty for perforated corneal melts. The stromal remainders of Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK) graft preparation were stored in 95% ethanol and used as emergency tectonic grafts for restoring globe integrity after sterile and infectious perforated corneal melts. In 6 cases with subtotal corneal melt, DMEK remainders (endothelium-denuded corneoscleral buttons) were used for 'limbus to limbus' tectonic epikeratoplasty and in 4 cases DSAEK remainders (anterior stroma) were used to seal focal perforated melts. Graft storage time was 5.1 ± 4.9 (ranging from 0.5 to 17) months. The surgeries were successful in all cases with restitution of the globe integrity. During the postoperative course 4 cases developed a graft melt (corneoscleral button for limbus to limbus tectonic epikeratoplasty, n = 3; lamellar patch, n = 1) within 2-6 months after the initial procedure. Three patients underwent successful repeat tectonic epikeratoplasty. In the fourth case of graft melt the globe was enucleated due to underlying expulsive haemorrhage and severe pain. The short-term results of the present case series suggest that the use of ethanol-stored stromal remainder of donor corneas after endothelial keratoplasty is an efficient temporary measure for tectonic restoration of perforated corneas.

Femtosecond Laser-Assisted Small Incision Endokeratophakia Using a Xenogeneic Lenticule in Rhesus Monkeys.

PURPOSE: To evaluate the feasibility and safety of xenogeneic endokeratophakia in rhesus monkeys and to explore the effects of a concave lenticule on refractive power. METHODS: Three adult New Zealand white rabbits and 6 healthy rhesus monkeys were used. The xenogenic concave grafts were created from the rabbits using a modified small incision lenticule extraction technique; after being cryopreserved in glycerol for 1 week, the grafts were implanted into the monkey recipient corneas. Spherical equivalent (SE), central corneal thickness, and keratometry curvature were assessed preoperatively, 1 week, 1, 4 and 6 months postoperatively. The quality of the xenogenic graft was also assessed by slit-lamp microscopy, in vivo confocal microscopy, and optical coherence tomography with anterior segment imaging. RESULTS: The graft appeared to be swollen a day after the operation but reduced considerably after a week. A trend of a lower refractive power (hyperopic shift) was demonstrated in relation to the SE after concave graft implantation. The mean SE increased from -0.60 ± 1.31 (median -0.69, interquartile range -1.00 to 0.50) preoperatively to 0.75 ± 1.27 (median 1.38, interquartile range -0.25 to 1.63) at 1 month postoperatively (P = 0.01). Central corneal thickness was significantly thicker each time after surgery compared with that recorded preoperatively (P < 0.01). The anterior and posterior interface between the graft and stroma was visible during the study. Corneal nerve regeneration was evident at 6 months postoperatively. The xenogeneic concave graft was stable and transparent at follow-up. Severe adverse events or evidence of a rejection response were not observed. CONCLUSIONS: Femtosecond laser-assisted small incision endokeratophakia using a xenogeneic corneal lenticule seems to be feasible and safe, which may provide a new method for myopia correction and keratoconus treatment.

Using Donor Lenticules Obtained Through SMILE for an Epikeratophakia Technique Combined With Phototherapeutic Keratectomy.

PURPOSE: To investigate the feasibility, safety, and efficacy of using a donor lenticule created during small incision lenticule extraction (SMILE) in an epikeratophakia technique combined with phototherapeutic keratectomy (PTK). METHODS: Six patients with decreased visual acuity due to a recurrence of corneal dystrophy were included in this prospective pilot study. PTK was performed using the MEL 80 excimer laser (Carl Zeiss Meditec, Jena, Germany) followed by the transplantation of donor lenticules onto the recipient eyes. These lenticules were extracted during SMILE procedures using the VisuMax femtosecond laser (Carl Zeiss Meditec) on 6 donors with myopia and served as the epikeratophakia tissue. RESULTS: The surgeries and postoperative follow-up examinations were uneventful and no complications were noted over 6 months of follow-up. The epithelium remodelling was achieved within 1 month. At the last measurement, the corrected distance visual acuity of all recipient eyes gained at least two lines. Five eyes (83.3%) gained at least two lines of uncorrected distance visual acuity compared to their preoperative levels. Mean keratometric power increased by 5.97 ± 3.73 diopters and central corneal thickness increased by 55.25 ± 36.38 µm. The epithelium healed and the lenticules remained clear over the follow-up period as observed under slit-lamp examination. Anterior segment optical coherence tomography observation showed the lenticule was transparent with a visible demarcation line during the follow-up examination. CONCLUSIONS: The use of a SMILE lenticule as a donor lenticule for an epikeratophakia technique appears feasible and safe in the short term. The predictability and long-term effects need further investigation. [J Refract Surg. 2016;32(12):840-845.].

A Case of Cataract Surgery in an Epikeratophakia Patient

PURPOSE: To report a case of cataract surgery in an epikeratophakia patient. CASE SUMMARY: A 59-year-old female with a history of epikeratophakic surgery 20 years ago complained of decreased visual acuity of both eyes for several months. She had nucleosclerotic and posterior subcapsular types of cataracts. Phacoemulsification and posterior capsule intraocular lens implantation were performed in both eyes. During surgery, corneal edema was especially prominent at the cornea with epikeratophakic lenticules in both eyes. In the left eye, severe corneal edema after one day of surgery was observed; however, after one week, corneal edema had subsided and visual acuity of both eyes had improved. CONCLUSIONS: When it necessary that cataract surgery is performed in patients with epikeratophakic lenticules, it is important to anticipate the corneal edema intraoperatively and postoperatively. Moreover, the surgeon should consider the acute calculation of the target refraction of intraocular lens in an epikeratophakia patient.

Long-term follow-up of epikeratophakia.

UNLABELLED: We report a 28-year follow-up of epikeratophakia surgery after extracapsular extraction of a congenital cataract. The patient's ocular history included the diagnosis of bilateral cortical congenital cataracts at 2 years of age, which was more severe in the right eye than in the left. One year later, the visual acuity in the right eye progressively worsened, and extracapsular cataract extraction without intraocular lens implantation was performed. After contact lens fitting failed, an epikeratophakia procedure was performed in the right eye. Twenty-eight years after the procedure, the patient was referred to Bascom Palmer Eye Institute for progressive loss of visual acuity in the left eye. It was discovered that the right eye had remained stable; the corrected distance visual acuity was 20/30 with a manifest refraction of -8.75 + 0.50 × 105. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Corneal scarring from laser in situ keratomileusis after epikeratoplasty: clinical and histopathologic analysis.

A 47-year-old woman required penetrating keratoplasty in the right eye after developing delayed visually significant corneal scarring bilaterally after laser in situ keratomileusis (LASIK) in 1997 following epikeratoplasty in 1987. Spectral domain ocular coherence tomography of the left cornea showed a 100 µm lenticule with a LASIK flap posterior to the host Bowman layer at 250 µm. Histopathology and electron microscopy of the right corneal button showed a 120 µm lenticule with a LASIK flap within the lenticule at 100 µm. Clinically significant scarring was present within the LASIK flap interface, within the lenticule stroma, and within the area of the underlying host Bowman layer. There were keratocytes at the junction between the LASIK flap and lenticule stromal bed. Although epikeratoplasty is no longer practiced, post-epikeratoplasty patients may present for refractive surgical options and LASIK carries significant risks for corneal scarring in these individuals, especially when using flap-creating devices that may create thin LASIK flaps.

Anatomical and functional graft survival, 10 years after epikeratoplasty in keratoconus.

PURPOSE: To report outcomes of epikeratoplasty in keratoconus (KC), utilizing manually-prepared plano donor lenticules in terms of flattening of the cone, reduction in astigmatism and improvement in the visual acuity. MATERIALS AND METHODS: Patients with KC, having visual acuity <20/200, astigmatism >12 diopters (D) but without corneal opacity underwent epikeratoplasty, using manually prepared plano donor lenticules from fresh or M.K preserved corneas, between 1990 - 2000 and followed for 10 years, were included in this report. Visual acuity slit-lamp-biomicroscopy, keratometry, and refraction were performed at 8 weeks, 12 weeks, and 6 months for all 59 patients. The same were carried out at 1 year, 5 years, and 10 years depending upon the availability of the patient for that period. RESULTS: Of the 59 patients, only 26 were available for follow-up after 10 years. At 3 months, 1 year and 5 years, best corrected visual acuity of (BCVA) ≥20/60 were achieved in 84.7%, 84.4% and 80.3% of eyes, respectively. BCVA was 73% at 10-year follow- up, which was due to the presence of posterior subcapsular cataract (PSC). The average keratometric astigmatism and average flattening in diopters stabilized at the end of 3 months, which remained constant at 1, 5, and 10-year follow-up. The average diopter of myopia was stabilized by 1 year, which was almost same at 10 year. Graft was clear in all but 1 eye at 10 year follow-up. CONCLUSION: Epikeratoplasty is a useful technique for keratoconic eyes without apical scarring who fail or unable to use contact lenses.

Lamellar corneal transplantation.

Penetrating keratoplasty (PK) has been the gold standard for the surgical treatment of most corneal pathologies; lamellar keratoplasty that only replaces the diseased corneal layers has recently evolved as an alternative, however. Innovations in surgical technique and instrumentation provide visual outcomes comparable to PK. We review the indications and outcomes of various techniques of anterior lamellar surgery developed to treat stromal disorders. Similarly, we discuss posterior lamellar keratoplasty techniques such as Descemet stripping automated endothelial keratoplasty and Descemet membrane endothelial keratoplasty. Posterior lamellar keratoplasty provides faster visual rehabilitation than PK in cases of Fuchs endothelial dystrophy and pseudophakic bullous keratopathy. In addition, for medically unresponsive infectious keratitis, therapeutic anterior lamellar keratoplasty yields similar graft survival to PK without an increased risk of disease recurrence.

Advanced topography-guided (OcuLink) treatment of irregular astigmatism after epikeratophakia in keratoconus with the WaveLight excimer laser.

PURPOSE: To evaluate the feasibility, safety, and predictability of treatment for high irregular astigmatism with advanced topography-guided laser epithelial keratomileusis in symptomatic eyes after epikeratophakia (EP) for keratoconus. METHODS: In a prospective case series, 10 consecutive eyes (10 patients) with high irregular astigmatism after epikeratophakia for keratoconus received OcuLink laser-assisted subepithelial keratectomy (LASEK) using the Allegretto Wave excimer laser. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifestation and refraction, corneal topographic examination with asphericity, and regularity were evaluated. All patients could not tolerate contact lens wear and had subjective symptoms. RESULTS: The UCVA improved from 0.61 ± 0.27 logarithm of the minimum angle of resolution (logMAR) (range, 0.3-1.0 logMAR) to 0.27 ± 0.07 logMAR (range, 0.2-0.4 logMAR), and the BSCVA improved from 0.25 ± 0.14 to 0.15 ± 0.09 logMAR (range, 0-0.3 logMAR) at 6 months after surgery. One patient had reduced UCVA (1 line), but no patients had reduced BSCVA. The refractive cylinder improved from -3.82 ± 2.43 diopters (D) (range, -0.75 to -7.75 D) to -1.43 ± 0.95 D (range, -0.25 to -2.50 D). The index of surface variance (an indicator of corneal surface irregularity) reduced from 115.1 ± 21.1 (range, 90-153) to 68.4 ± 18.2 (range, 39-95). Subjective symptoms, such as glare, halos, ghost images, starbursts, and monocular diplopia, were either not present or obviously alleviated. CONCLUSIONS: Advanced topography-guided (OcuLink) LASEK can significantly reduce irregular astigmatism and increase the UCVA and BSCVA.

[Perspectives of femtosecond laser-assisted keratoplasty]. / Perspektiven der Femtosekundenlaser-assistierten Keratoplastik.

The femtosecond laser technique allows completely new trephination procedures in penetrating and lamellar keratoplasty. With femtosecond laser-assisted penetrating keratoplasty it is possible to perform profiled trephination, such as top hat and mushroom profiles. Thus, it is easier to get a watertight wound closure intraoperatively and due to the larger wound surface wound healing is faster and allows early complete suture removal. In lamellar keratoplasty the femtosecond laser enables the surgeon to cut to any depth in the corneas resulting in thin corneal donor buttons, e.g. for DSAEK. In this manuscript an overview is given of the state of the art and of the perspectives of femtosecond laser keratoplasty.

Accommodating intraocular lens implantation in an epikeratophakia patient.

We report a case of implantation of the Crystalens AT-45SE and AT-52SE intraocular lenses in a highly myopic patient who had bilateral epikeratophakia surgery 15 years previously. Lessons learned from the first eye were taken into consideration when selecting the dioptric power for the fellow eye. With secondary interventions and meticulous lens calculations, the final outcomes were excellent and equivalent, allowing the patient to achieve uncorrected distance and intermediate visual acuities of 20/25 and near visual acuity of 20/50 in both eyes. To our knowledge, this is the first reported case of accommodating lens implantation in an epikeratophakic eye.

[Results of tectonic epikeratoplasty in the management of corneal perforations]. / Wyniki epikeratoplastyki tektonicznej w leczeniu perforacji rogówki.

PURPOSE: To present therapeutic application of tectonic epikeratoplasty as logical patch in severe ocular surface disorders. MATERIAL AND METHODS: Full thickness corneo-scleral transplants, 14 mm in diameter were used in 67 operations of 41 patients with corneal perforation or descemetocele. (14 women and 27 men), in the period 1998-2008. The mean age of patients was 55.2 +/- 17.7 years (range 15-82). The transplants were sutured over the limbus or the scleral rim and was implanted under the conjunctiva after 360 degrees peritomy. Donor tissue unsuitable for penetrating keratoplasty because of poor endothelium or corneal scarring, was obtained from Lublin Eye Bank. RESULTS: We observed closing of the perforation in all cases. Healing of the ulceration with scar formation and new vessels ingrowth was noted. In some eyes repeated epikeratoplasties were performed. CONCLUSIONS: Tectonic epikeratoplasty is a safe and simple method of treatment of corneal perforations. It provides a biological patch stimulating the healing of corneal defects. It gives time for systemic treatment before further ocular surface reconstructive procedures can be performed.

[Refractive surgery]. / Refraktive Chirurgie.

The surgical correction of refractive errors has gained widespread acceptance in the past 20 years, mainly through the introduction of the excimer laser. The excimer is used to ablate the cornea, renoving stromal tissue in the center (to correct myopia through flattening of the surface), or in the midperiphery (to steepen the cornea to correct hyperopia). Although excimer procedures dominate the field of refractive surgery, other approaches are also available. In the cornea itself, ring segments can be implanted, heat-induced coagulation effects can produce steepening, and cross-linking of the collagen fibers can stiffen a weakened structure. While all corneal procedures are extraocular, refractive surgery can also be performed within the eye. Special intraocular lenses can be implanted in the anterior chamber angle, fixated onto the iris, or placed in the posterior chamber in front of the crystalline lens. These so-called phakic intraocular lenses are available in different optical magnitudes and act to correct the patient's refractive error. Prebyopic individuals can have the crystalline lens removed in a procedure identical to cataract surgery. In such cases the lens is extracted even though no cataract is present, and an intraocular lens is implanted in the now empty capsular bag of the crystalline lens. The implanted lens serves to correct the preoperative refractive error.

Long-term microstructural changes following epikeratophakia: in vivo confocal microscopy study.

The unilateral epikeratophakic eye of a 20-year-old woman with a history of congenital cataracts was examined using laser scanning in vivo confocal microscopy 17 years after transplantation. In vivo confocal microscopy demonstrated a reduced keratocyte density in the grafted lenticule and the host stroma, with unusual elongated and tortuous hyperreflective branching structures in the anterior stroma of the host cornea. The sub-basal nerve plexus was present in the lenticule, although with a reduced nerve density. The appearance of the host endothelium was similar to that observed in Fuchs endothelial dystrophy. Dramatic microstructural changes were observed in almost all layers of the cornea 17 years after epikeratophakia. Although no longer performed as routine practice, in vivo confocal microscopy examination of epikeratophakia has provided fascinating insight into the potential corneal adaptations at a cellular level.

[Deep anterior lamellar (DALK) vs. penetrating keratoplasty (PKP): a clinical and statistical analysis]. / Tiefe lamelläre Keratoplastik vs. perforierende Keratoplastik: Klinische und statistische Analyse.

PURPOSE: Results of deep anterior lamellar keratoplasty (DALK) have been analysed regarding the BCVA, cylinder values, endothelial cell counts and complications both clinically and statistically. An answer to the question is sought as to whether DALK is an equal or better alternative to penetrating keratoplasty (PKP) given all indications with intact corneal endothelium. PATIENTS AND METHOD: A consecutive series on 166 eyes is compared to a group of 566 consecutive PKP eyes regarding visual acuity, astigmatism, stability of refraction and endothelial cell count. The operations were performed in one centre by the same surgeon with the same trephine (Guided Trephine System, GTS) and special instrumentation for DALK (Geuder, Heidelberg). All transplants were of a diameter of 8 mm, the fixation was done with the double-running antitorque suture with one exception. All cases of DALK and PKP were analysed first as two overall groups, then subgroups were broken down for keratoconus and endothelial cell counts (ECC). The subgroups comprised 135 DALK and 76 PKP eyes. RESULTS: BCVA was identical over the whole follow-up of 5 years for the overall groups of DALK and PKP. Statistically significant differences could only be found for the first 3 months favouring DALK (Median 0.5 to 0.35, p = 0.001), whereas for both groups BCVA was without statistically significant differences from month 6 through to 5 years. In the subgroups DALK versus PKP in keratoconus none of the medians from the 1st month to the 5th year were statically significantly different. Between the 1st and 2nd year a maximal BCVA of median 0.7 was reached. The analysis of the endothelial cell count shows both for the comparison of the overall groups and the subgroups keratoconus highly significant differences favouring DALK for all time intervals. CONCLUSION: Since stable ECC suggest an unlimited lifetime of DALK and there is no clinical difference in the outcomes of BCVA or cylinders it must be concluded that with the data presented the DALK operation should be preferred over PKP in eyes that preoperatively have normal endothelial cell counts.