Penetrating Keratoplasty For Keratoconus Research Articles

Risk factors for corneal graft rejection after penetrating keratoplasty for keratoconus.

To evaluate the association between donor-related factors and the risk of rejection in patients undergoing penetrating keratoplasty (PKP) for keratoconus. A retrospective review was performed of keratoconus patients with no corneal neovascularization who underwent PKP from November 2014 to December 2016 and completed at least two years of follow-up. Preoperative, donor, operative, and postoperative data were collected and analyzed to identify factors leading to corneal graft rejection. A total of 201 eyes (of 201 patients) that underwent PKP for keratoconus were included. Of these, 22.9% (95% CI 17.6-29.2%) had an episode of graft rejection. The overall graft survival rate was 98.5%. Receipts with a history of corneal transplant in the fellow eye (IRR 1.69, 95% CI 1.01, 2.80; p = 0.044) and those with postoperative stromal neovascularization (IRR 2.51, 95% CI 1.49, 4.21; p = 0.001) had a significantly higher incidence of rejection than those without these features. In univariate analysis, death-to-surgery time and death-to-excision time (DET) showed a weak association with graft rejection (p 0.05 and 0.08 respectively); However, in the multivariable analysis, this significance was lost. Grafts with a death-to-excision time (DET) greater than 8 h had a 0.53X lower risk of rejection compared with grafts with DET within 8 h or less (p = 0.05). Rejection was higher in patients receiving grafts with a preservation time within 7 days or less compared with preservation time greater than 7 days (30.6% vs. 21.2%, respectively, p = 0.291). In the multivariable analysis, none of the donor-related factors were significantly associated with graft rejection; however, short death-to-surgery time may be associated with rejection after PKP. Recipients with a history of PKP in the fellow eye and those who developed corneal neovascularization were also at increased risk of developing rejection after keratoplasty.

Main issues in penetrating keratoplasty.

This review explores contemporary challenges in penetrating keratoplasty (PK), focusing on technical intricacies, technological advancements, and strategies for preventing graft rejection. A systematic literature search from January 2018 to July 2023 was conducted across PubMed, Cochrane, Web of Science, Scopus, and EMBASE. The inclusion criteria comprised studies on PK and its comparison with other corneal pathologies, with emphasis on keratoconus (KC). Two independent reviewers screened studies, extracting relevant data. The review covers PK evolution, highlighting infra-red femtosecond lasers' impact on graft shapes, minimizing astigmatism, and enhancing wound healing. Graft rejection, a primary complication, is examined, detailing risk factors and preventive measures. Preoperative considerations, diagnostic techniques for rejection, and PK in KC are discussed. Postoperative care's significance, including intraocular pressure monitoring and steroid administration, is emphasized. The paper concludes with a comprehensive approach to prevent graft rejection, involving topical and systemic medications. An outlook on evolving monoclonal antibody research is presented. As the field progresses, personalized approaches and ongoing therapeutic exploration are expected to refine strategies, enhancing PK outcomes.

Analysis of visual and refractive results after wedge resection for high astigmatism after penetrating keratoplasty in keratoconus.

To analyze visual and refractive results after wedge resection to correct high astigmatism after penetrating keratoplasty (PK) for keratoconus. Cornea Unit of the Centro de Oftalmología Barraquer Barcelona, Spain. A retrospective quasi-experimental, before and after study. Patients who developed high astigmatism or ectasia in the graft-host junction after PK were treated with wedge resection. The following variables were studied before the surgery, 1-year after and at the final visit: uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refractive and topographic astigmatism and spherical equivalent. Vectorial analysis of the astigmatism changes was performed. Fifty-one eyes were included with a mean follow-up of 4.19 ± 3.09 years. Mean refractive astigmatism was 11.47 ± 3.57 diopters (D) pre-operatively and 4.79 ± 3.32 D at the final follow-up (p < 0.001). The mean centroid changed from 2.65 ± 11.82 D at 23 degrees preoperatively to 0.35 ± 5.86 D at 127 degrees postoperatively. Concerning spherical equivalent, the mean preoperative value was -3.10 ± 4.15 D and the mean postoperative value was -1.55 ± 3.41 D (p = 0.002). Mean pre-operative and final follow-up UDVA were 1.25 ± 0.27 and 0.84 ± 0.50 (p < 0.001). Mean Pre-op and final follow-up CDVA were 0.27 ± 0.19 and 0.24 ± 0.24. Wedge resection is a useful surgical procedure to correct high astigmatism. It is a safe technique with moderate efficacy and may be considered as initial procedure of choice in high astigmatism due to long-term ectasia in the graft-host junction after PK for keratoconus.

Risk Factors of Urrets-Zavalia Syndrome after Penetrating Keratoplasty.

Objective: The objective of this study was to analyze the clinical features and risk factors of Urrets-Zavalia syndrome (UZS) after penetrating keratoplasty (PKP). Methods: The medical records of 152 patients who underwent PKP at the Department of Ophthalmology, Tongji Hospital, between January 2014 and December 2016 were retrospectively reviewed. UZS was diagnosed based on pre- and post-operative pupillary findings. The relationships among the primary disease, postoperative intraocular pressure (IOP), and the incidence of UZS were statistically analyzed. The pupillary changes during the follow-up period were studied. Results: Among the 152 included patients, 23 were diagnosed with UZS, with an incidence of 15.13%. The primary diseases of the UZS patients were keratoconus (eight cases, 34.78%), viral keratitis (six cases, 26.08%), leukoma (four cases, 17.39%), fungal corneal ulcer (two cases, 8.70%), corneal endothelial decompensation (two cases, 8.70%), and corneal degeneration (one case, 4.35%). The incidence of UZS in keratoconus patients was higher than that in patients with fungal corneal ulcer (42.11% versus 6.25%, p = 0.003); In addition, the transient postoperative high IOP was not significantly related to the incidence of UZS in keratoconus patients in our study (p = 0.319). Twenty-one patients with UZS were followed up for >6 months, seven of whom (33.33%) recovered spontaneously (within the range of 48 days to 1.5 years). Conclusion: In our study, the incidence of UZS after PKP was 15.13%, and 33.33% of these patients recovered spontaneously. UZS may be more likely to occur in patients with keratoconus. Postoperative transient high IOP may increase the incidence of UZS after PKP for keratoconus.

Topography-Guided Trans-Epithelial No-Touch Photorefractive Keratectomy for High Irregular Astigmatism After Penetrating Keratoplasty: A Prospective 12-Months Follow-Up.

PurposeTo describe the efficacy and safety of topography-guided trans-epithelial no-touch photorefractive keratectomy (PRK) for the correction of highly irregular astigmatism after penetrating keratoplasty (PK).Patients and MethodsA prospective study was conducted on 12 eyes of 12 patients affected by highly irregular astigmatism after PK for keratoconus. Each patient underwent a single-step topography-guided trans-epithelial ablation (CIPTA®2 software, iVis Technologies). Corneal topography data as well as uncorrected (UDVA) and corrected distance visual acuity (CDVA) and spherical equivalent (SEQ) were collected preoperatively (T0) and at 1 (T1), 3 (T2) and 12 (T3) months after surgery.ResultsMean UDVA and CDVA significantly improved, respectively, from 1.22±0.17 and 0.18±0.03LogMAR at T0 to 0.63±0.17 (CI 95%, P<0.001) and 0.04±0.03LogMAR at T3 (CI 95%, P<0.001). Mean SEQ significantly decreased from −3.75±1.32 to –1.60±1.32D (CI 95%, P<0.02). Mean subjective refractive astigmatism (SRAST) and mean keratometry astigmatism (SimK) significantly decreased, respectively, from 7.83±0.98 and 8.10±1.48D to 2.83±0.98 and 5.29±1.48D (CI 95%, P<0.001). Corneal Morphological Irregularity index (CMI) significantly decreased from 62.76±7.26 µm to 23.24±7.26 µm (CI 95%, P<0.001). Apart from a single episode of graft rejection 5 days after ablation, successfully reverted with topical steroids, no other complications were noted. A mild corneal haze was observed in two eyes (16.7%) at 3 months post-PRK, and no regression was observed at 12 months.ConclusionOur study demonstrates the safety and long-term effectiveness of a trans-epithelial topography-guided ablation in the treatment of post-PK highly irregular astigmatism.

Biomechanical Effects of Deep Anterior Lamellar Keratoplasty and Penetrating Keratoplasty for Keratoconus: A Finite Element Analysis.

PurposeTo theoretically compare corneal displacement and the von Mises (VM) stress distribution of deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) for keratoconus (KC) and to evaluate the effects of residual stromal thickness (RST) and intraocular pressure (IOP) on postoperative corneal biomechanics.MethodsWe performed DALK and PK simulations using Ansys by employing anisotropic nonlinear hyperelastic corneal material properties. We analyzed corneal displacement and VM stress in DALK and PK models under IOPs of 10, 15, 20, and 25 mmHg. We established two DALK models: The ideal-type DALK ensured that postoperative central corneal thickness was constant at 560 µm and the corneal graft thickness varied with RST. The clinical-type DALK ensured that corneal grafts had the same thickness (500 µm) regardless of RST. Then we analyzed the effects of RST and IOP on postoperative corneal displacement and VM stress.ResultsCorneal displacement and VM stress were lower in the DALK than in the PK model. In the ideal-type DALK model, an increase in RST was associated with increased deformation and decreased VM stress in the healing zone, except for a RST of 0 µm. In the clinical-type DALK model, deformation and VM stress in the healing zone decreased with an increase in RST, except for a RST of 0 µm.ConclusionsDALK showed more stability than PK. For the ideal-type DALK model, an increase in RST resulted in decreased postoperative corneal biomechanics in the healing zone. For the clinical-type DALK model, corneal deformation and VM stress decreased with an increase in RST, which provides numerical evidence for the design of corneal transplantation for patients with KC.Translational RelevanceIn this computational modeling study, we first theoretically compared corneal biomechanics between DALK and PK for KC. Then, the effects of RST and IOP on postoperative corneal biomechanics were investigated. Our findings provide novel insights into the optimal design for corneal transplantation for patients with KC.

Traumatic wound dehiscence after penetrating keratoplasty for keratoconus: about a case

We report a case of a 35-year-old patient, who had undergone optical penetrating keratoplasty (PKP) for bilateral keratoconus in 2012. He was referred to ophthalmic emergency room for a blunt eye injury of the right eye. His visual acuity was reduced to light perception. Slit lamp examination revealed a dehiscence of PKP at 4 o´clock (extending from 2 o´clock to 7 o´clock) with flat anterior chamber, iris prolapse, total hyphema and corneal edema of the corneal graft (A). The posterior segment noted no complications. Suturing of the graft was performed; seven interrupted 10-0 monofilament nylon sutures were applied in the area of wound dehiscence (B). Follow-up was ensured for several months, during which visual acuity rose to 1/10. The scar from transfixing keratoplasty for keratoconus is at a high risk of rupture even with minor trauma. The prognosis for such a trauma is always severe and the post-traumatic course remains less pejorative, especially when there are lesions of the posterior segment.

Graft rejection-like reactions in the early postoperative period after deep anterior lamellar keratoplasty for keratoconus: a retrospective study.

BackgroundDeep anterior lamellar keratoplasty (DALK) is indicated to correct high astigmatism in patients with keratoconus (KC) and no evidence of Descemet’s membrane rupture. However, some patients with KC experience graft rejection-like inflammatory reactions within 2 months (usually in the first week) after DALK. The aim of this study was to identify the characteristics and influencing factors of these reactions by reviewing the records of patients who underwent DALK or penetrating keratoplasty (PKP) for KC or other corneal problems.MethodsWe retrospectively reviewed the medical records of patients who underwent DALK for KC (DALK/KC), PKP for KC (PKP/KC), or DALK for other corneal problems (DALK/non-KC) at Ban Buntane Hotokukai Hospital between January 2006 and December 2015 and who were followed for more than 1 year. We collected data on the characteristics and incidence of severe inflammatory graft reactions in the early postoperative phase (ie, within 2 months after keratoplasty) and visual outcomes after these inflammatory reactions.ResultsPostoperative inflammatory reactions characterized by persistent epithelial defects, loose suture with infiltration, and vessel invasion occurred in seven of eleven DALK/KC patients, three of 50 DALK/non-KC patients, and none of five PKP/KC patients. These reactions were nonresponsive to topical steroids, and suture removal was required. Although a clear corneal graft in the pupillary area was obtained and best-corrected visual acuity was good after the resolution of inflammation, a risk of corneal astigmatism remained.ConclusionThe incidence of these reactions in the early postoperative period is high after DALK for KC. These reactions do not respond well to topical steroids, and suture removal may be required, which may cause high astigmatism after the inflammation subsides. Lamellar keratoplasty should be considered carefully for patients with KC.

Comparison of visual and topographic outcomes of deep-anterior lamellar keratoplasty and penetrating keratoplasty in keratoconus.

To compare visual, surgical and topographic outcomes of deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) for keratoconus (KC). In this multicenter, prospective, randomized clinical trial 76 eyes of 71 KC patients operated between January 2011 and July 2014 in 2 tertiary referral hospitals were included. Consecutive patients were alternately selected to receive one of the two surgical methods. Thirty eight eyes underwent DALK with the big-bubble technique and 38 eyes underwent PK. Mean best spectacle corrected visual acuity (BSCVA) at the first postoperative week (P=0.012) and the first postoperative month (P<0.001) was statistically significantly higher in DALK group. The mean BSCVA at 12mo was not significantly different for DALK (0.30±1.99 logMAR) versus PK (0.40±0.33 logMAR) (P=0.104). The 76.3% of the eyes had a BSCVA over 0.5 in DALK and 47.4% in PK group (P=0.009). The 7.9% of the eyes had a BSCVA of 1.0 in DALK and 5.3% in PK group (P=0.644). Mean spherical equivalent was -2.94 D in DALK and -3.09 D in PK group. Mean topographic astigmatism was 4.62 D and 4.18 D respectively. Regular topographic patterns were observed in 31 (81.6%) of DALK and 29 (76.3%) of PK (P=0.574). The most frequent topographic pattern was oblate asymmetric bow tie, seen in 39.5% in DALK and 23.7% in PK. Big bubble DALK provides an earlier visual improvement compare to PK. However, visual and topographic outcomes are similar to those in PK at 1y. Postoperative complications including rejection and intraocular pressure elevation are more frequent in PK. DALK is a safer alternative to PK for KC. However, intraoperative perforation of the Descemet's membrane is a significant complication.

Trends in Corneal Transplantation in Keratoconus.

To determine recent trends in and sociodemographic/comorbid conditions associated with penetrating keratoplasty (PK) and lamellar keratoplasty (LK) for keratoconus (KCN). Patients with KCN and subsequent PK and LK procedures were identified using International Classification of Diseases, 9th revision (ICD-9) and Current Procedural Terminology (CPT) billing codes. The change in surgical rates was calculated over a decade, and multivariate analysis demonstrated factors associated with undergoing surgery. A total of 21,588 patients with KCN underwent 1306 PK procedures and 109 LK procedures during the study period. Individuals were significantly less likely to undergo PK from 2009 to 2012 compared with 2001 to 2008 [odds ratio (OR) 0.57, 95% confidence interval (CI) 0.47-0.68, P < 0.001]. Multivariate analysis revealed the factors that increased the likelihood of PK alone and included age 20 to 40 (OR 1.90, 95% CI, 1.19-3.04, P < 0.001), black race (OR 1.36, 95% CI, 1.06-1.74, P = 0.01), and education less than a bachelor's degree or only a high school diploma (OR 1.94-2.84, P < 0.001 for all comparisons). Female sex (OR 0.74, 95% CI, 0.63-0.88, P < 0.001) and household net worth either between 150 and 249k (OR 0.64, 95% CI, 0.48-0.84, P < 0.001) or more than $500,000 (OR 0.71, 95% CI, 0.51-0.99, P = 0.03) were traits associated with decreased odds of PK. No significant associations for LK were observed. The rate of PK in KCN is decreasing in the United States. The third or fourth decade of life, male sex, black race, lower education, and greater household net worth are associated with increased odds of PK.

Keratokonusas: 14-kos metų kiaurinės keratoplastikos ankstyvųjų pooperacinių rezultatų apžvalga

Keratokonusas – viena dažniausių kiaurinės keratoplastikos (KKP) priežasčių pasaulyje. Serga jauni, darbingo amžiaus žmonės, todėl pažengus ligai (vėlyvoje stadijoje), kai kiti gydymo metodai neefektyvūs, KKP gali grąžinti regą. Pastebėta, kad po donorinės ragenos persodinimo komplikacijų pasitaiko, tačiau dauguma recipientų patenkinti pooperaciniu rezultatu. Siekdami įvertinti dėl keratokonuso atliekamų KKP dažnį išanalizavome per 14-lika metų (2001-2014 m.) LSMUL KK Akių ligų klinikoje operuotų ligonių atvejus. Šiame straipsnyje aptarsime KKP dažnį, kai donorinės ragenos persodinimo priežastis - keratokonusas, sergančiųjų pasiskirstymą pagal amžių, lytį, pažeistą akį, taip pat ankstyvuosius pooperacinius rezultatus (regos aštrumo pokytį, pooperacinę eigą, komplikacijas), kataraktos ir glaukomos bei amžiaus reiškmę regos aštrumo pokyčiui. Retrospektyvinis tyrimas vykdytas gavus Bioetikos centro leidimą (Nr. BEC-MF-623). Nustatyta, kad 2001-2014 metais KKP dėl keratokonuso atlikta 71 akyje (24,83 proc.). 59 recipientams persodinta donorinė ragena vienoje akyje, 6 – abiejose akyse. Transplantacijų pasiskirstymas pagal pažeistą akį statistiškai reikšmingai nesiskiria (p=0,635): dešinės akies keratoplastika - 33 ligoniams (46,5 proc.), kairės – 38 ligoniams (53,5 proc.). 19 (26,8%) moterų, kurių amžiaus mediana 39 (27-46) metai ir 52 (73,2%) vyrai, amžiaus mediana 28,5 (25-36) metai. Imtyje vyrų buvo statistiškai reikšmingai daugiau nei moterų (p&amp;lt;0,001). Vyrų ir moterų amžius statistiškai reikšmingai skiriasi (p &amp;lt; 0,019). Nustatyta, kad po ragenos persodinimo 95,8 proc. recipientų regos aštrumas pagerėjo: nežymiai – 32,4 proc., vidutiniškai – 50,7 proc., ženkliai – 12,7 proc. Tik 4,2 proc. recipientų regos aštrumas nepakito ar net pablogėjo. Sklandi pooperacinė eiga (be užfiksuotų komplikacijų) buvo 40 (56,3 proc.) recipientų. 31 tiriamajam (43,7 proc.) stebėtos įvairios komplikacijos. Iš viso diagnozuoti 58 komplikacijų atvejai: 21 recipientui nustatyta viena iš komplikacijų, likusiems - dvi ir daugiau. Ragenos atmetimo reakcija – 14 (24,1proc.) recipientų, ragenos paburkimas – 13 (22,5 proc.) recipientų, siūlės (-lių) atsipalaidavimas – 12 (20,7 proc.) recipientų, akispūdžio padidėjimas – 8 (13,8 proc.) recipientų, transplantato vaskuliarizacija – 5 (8,6 proc.) recipientams, descemeto membranos raukšlės – 4 (6,9 proc.) recipientams, infiltracija apie siūles – 2 (3,4 proc.) recipientams. 2001-2014 metais LSMUL KK Akių ligų klinikoje 24,8 proc. KKP operacijų atlikta dėl keratokonuso. KKP dešinėje ir kairėje akyse atliktos vienodai dažnai (46,5 proc. v.s. 53,5 proc., p&gt;0,635). Donorinės ragenos persodinimo operacija dėl keratokonuso dažniau taikyta vyrams nei moterims (73,2proc. vs. 26,8 proc., p&amp;lt;0,001) ir atlikta 10,5 metų jaunesniame amžiuje (p&amp;lt;0,019). Po kiaurinės keratoplastikos 95,8 proc. atvejų regos aštrumas pagerėjo ir tik 4,2 proc. nepakito, ar net pablogėjo. Jokių komplikacijų nebuvo 40 (56,3 proc.) recipientų. Dažniausia komplikacija - ragenos atmetimo reakcija (24,1 proc.).

Penetrating Keratoplasty for Keratoconus With and Without Resolved Corneal Hydrops: Long-term Results

To evaluate the long-term risk of endothelial rejection, graft survival, and associated factors following penetrating keratoplasty (PK) for keratoconus, with and without prior resolved corneal hydrops. Retrospective cohort study. Primary outcome measures were endothelial rejection-free survival and failure-free survival. Secondary outcome measures were corneal neovascularization following hydrops and complications following PK. A total of 245 eyes underwent PK for keratoconus with mean follow-up of 5.6 ± 3.6 years. Eyes with prior hydrops (n= 74) had lower endothelial rejection-free survival rates compared with eyes without prior hydrops: 86.5% ± 4.0% vs 86.5% ± 2.6% at 1 year, 61.0% ± 6.2% vs 76.9% ± 3.3% at 5 years, and 45.8% ± 10.1% vs 70.9% ± 4.3% at 10 years, respectively (P= .023). Multivariate analysis identified factors associated with endothelial rejection as age ≤25 years (P= .017), corneal neovascularization (P= .001), donor trephination size >8mm (P= .017), and poor clinic attendance (P= .015). There was no difference in the failure-free survival rates with and without prior hydrops: 98.6% ± 1.3% vs 97.1% ± 1.3% at 1 year, 97.3% ± 1.9% vs 95.1% ± 1.9% at 5 years, and 97.3% ± 1.9% vs 92.2% ± 2.7% at 10 years, respectively (P= .42). Corneal neovascularization was present at the time of PK in 44.6% of eyes with prior hydrops and 7.6% without prior hydrops (P < .001). Corneal neovascularization, a frequent complication of corneal hydrops, was associated with increased risk of endothelial rejection following PK. However, allograft survival was similar in eyes with and without prior hydrops.

Long-term results of lasik refractive error correction after penetrating keratoplasty in patients with keratoconus

ObjectiveTo evaluate the long term results of Lasik for residual refractive errors (RE) after penetrating keratoplasty (PKP) for keratoconus (KC). DesignRetrospective cohort. MethodRecords of 14 consecutive patients (19 eyes) who had Lasik after PKP for KC were retrospectively reviewed. In all eyes with refractive stability and suture removed before Lasik, far distance Visual Acuity with (AVCC) and without correction (AVSC), spherical equivalent (EE), refractive (Ast) and keratometric (dK) astigmatism were analyzed pre- and post-operatively before and after one year of follow up. Data were analyzed using Shapiro–Wilk normality test, Student t test and Mann–Whitney test. A p-value of <0.05 was considered statistically significant. ResultsThe mean follow-up time was 3.16 months for the follow-up before one year postoperative and 5.8 years for the follow-up after one year postoperative. The best spectacle corrected visual acuity of 0.11 LogMAR (DE 0.07) before Lasik remained stable throughout the study. The SE decreased from −2.6 (DE 3.53) to −0.36 D (DE 1.33) (p<.05) for the follow-up before one year postoperative and −1.28 D (DE 1.63) (p=.07) for the follow-up after one year postop. The refractive cylinder was reduced from −3.43 (DE 1.35) preoperative to −1.37 D (DE 1.24) (p<.05) and −3.21 D (DE 2.29) (p=.36) in the long term after one year of follow-up. ConclusionsLasik refractive results regress one year after the operation; therefore it is not an effective long-term surgical refractive procedure for residual refractive errors after PKP for KC.

Resultados a largo plazo de lasik para ametropía residual en queraplastia penetrante en pacientes con queratocono

ObjectiveTo evaluate the long term results of Lasik for residual refractive errors (RE) after penetrating keratoplasty (PKP) for keratoconus (KC). DesignRetrospective cohort. MethodRecords of 14 consecutive patients (19 eyes) who had Lasik after PKP for KC were retrospectively reviewed. In all eyes with refractive stability and suture removed before Lasik, far distance Visual Acuity with (AVCC) and without correction (AVSC), spherical equivalent (EE), refractive (Ast) and keratometric (dK) astigmatism were analyzed pre- and post-operatively before and after one year of follow up. Data were analyzed using Shapiro-Wilk normality test, Student t test and Mann-Whitney test. A P-value of <0,05 was considered statistically significant. ResultsThe mean follow-up time was 3.16 months for the follow-up before one year postoperative and 5.8 years for the follow-up after one year postoperative. The best spectacle corrected visual acuity of 0,11 LogMAR (DE 0,07) before Lasik remained stable throughout the study. The SE decreased from −2.6 (DE 3.53) to −0,36 D (DE 1.33) (P<.05) for the follow-up before one year postoperative and −1.28 D (DE 1.63) (P=.07) for the follow-up after one year postop. The refractive cylinder was reduced from −3.43 (DE 1.35) preoperative to −1.37 D (DE 1.24) (P<.05) and −3.21 D (DE 2.29) (P=.36) in the long term after one year of follow-up. ConclusionsLasik refractive results regress one year after the operation; therefore it is not an effective long-term surgical refractive procedure for residual refractive errors after PKP for KC.

Analysis of the Etiologies and the Classification of Fixed Dilated Pupil after Intraocular Surgery

Purpose: To seek for mechanisms to prevent fixed dilated pupil including Urrets-Zavalia syndrome after intraocular surgery by analyzing and classifying the causes of such cases. Methods: Medical records and anterior segment photographic images of patients with fixed dilated pupil who underwent penetrating keratoplasty, lamellar keratoplasty, or cataract surgery were analyzed in a retrospective manner from April, 1984 to February, 2014. Results: Among 15 cases of postoperative fixed dilated pupil, 8 eyes of keratoconus eyes had received penetrating keratoplasty done and 7 eyes with ocular disorders other than keratoconus underwent intraocular surgeries. In cases 1 and case 2, which received penetrating keratoplasty for keratoconus, dilated pupil with regular pupil border, iris atrophy, and secondary glaucoma occurred; these cases were classified as group 1 and diagnosed as Urrets-Zavalia syndrome. Cases from 3 to 8 which also received penetrating keratoplasties due to keratoconus, irregularly dilated pupil, severe iris atrophy, posterior synechiae after moderate to severe inflammation in the anterior chamber, and fibrotic membrane on the anterior capsule occurred; these cases were classified as group 2. Finally, cases 9 to 15, which had mild inflammation, no fibrotic membrane, and regularly fixed dilated pupil after receiving other intraocular surgeries were classified as group 3. Conclusions: Differences exist between definite Urrets-Zavalia syndrome and postoperative fixed dilated pupil with regards to regularity of pupillary margin, degree of iris atrophy, posterior synechiae, fibrotic membrane, and posterior subcapsular opacity. Therefore, a new classification of fixed dilated pupil after intraocular surgery which addresses these characteristics is required and various trials to prevent the adverse postoperative complications of fixed dilated pupil should be performed. Preventive measures may include careful control of intraocular pressure, restricting atropine use, completely removing of viscoelastics, and minimal air or gas injection. J Korean Ophthalmol Soc 2015;56(1):47-54

Topoplastia de Cvintal assistida por laser de femtossegundo

Apresentamos um relato de astigmatismo tardio progressivo pos-transplante de cornea para ceratocone, associado a afinamento periferico na juncao doador-receptor, o que presumidamente pode ser considerado como recorrencia da ectasia. O caso foi tratado por meio de Topoplastia de Cvintal assistida por laser de femtossegundo para a confeccao da incisao com geometria top hat, seguido de sutura com ajuste per-operatorio guiado por ceratoscopia.

Urrets-Zavalia syndrome following penetrating keratoplasty for keratoconus

Urrets-Zavalia syndrome (UZS) consists of a fixed dilated pupil associated with iris atrophy. It is a poorly understood complication following penetrating keratoplasty (PKP) for keratoconus (KC). In this work, we aim to establish the incidence, visual outcomes, and an understanding of UZS. This was a retrospective single-center study in a tertiary eye service in the United Kingdom of consecutive patients with UZS following PKP for KC in a 10-year period. Post-operative complications, including raised intraocular pressure (IOP), were recorded. UZS patients and age-matched control patients who had undergone PKP for KC without developing UZS attended a comprehensive clinical assessment. Anterior segment indocyanine green (ICG) angiography assessed iris perfusion. The incidence of UZS was 16.2 %. There was no difference in LogMAR VA or Pelli-Robson contrast sensitivity between groups. There was higher first-day post-operative IOP in UZS (p = 0.02). UZS patients had increased pupil size (p = 0.09) with reduced response to pilocarpine 2 % (p < 0.001). ICG angiography revealed delayed/reduced iris vasculature filling in UZS compared with normal filling patterns of controls. Elevated post-operative IOP within 24 h was a significant factor in the development of UZS. Visual function in UZS patients was unaffected. UZS patients developed longstanding mydriasis with reduced reactivity to topical pilocarpine 2 %. ICG angiography confirmed iris vessel ischemia; supporting the theory that iris ischemia resulting from occlusion of iris root vessels due to elevated IOP causes UZS. We advocate rigorous intraoperative management of ocular viscoelastic devices and aggressive postoperative IOP control in patients undergoing PKP for KC.

Photorefractive keratectomy with mitomycin-C after corneal transplantation for keratoconus

To evaluate the efficacy of photorefractive keratectomy (PRK) for residual refractive error after penetrating keratoplasty (PKP) for keratoconus. Private ophthalmic clinic. Case series. Consecutive patients who had PRK augmented with topical mitomycin-C (MMC) after PKP for keratoconus were retrospectively reviewed. Patients were divided into a a low cylinder group (refractive cylinder ≤ 6.00 D) and a high cylinder group (refractive cylinder >6.00 D). Visual acuity, refraction, and keratometry were analyzed preoperatively and 1, 3, 6, and 12 months postoperatively. The study comprised 47 eyes (41 patients). The spherical equivalent (SE) decreased from -4.24 D ± 3.23 (SD) preoperatively to -0.71 ± 1.03 D 12 months postoperatively in the low cylinder group and from -4.19 ± 3.54 D to -2.45 ± 3.42 D, respectively, in the high cylinder group. The refractive cylinder decreased from -4.27 ± 1.4 D to -1.71 ± 1.55 D, respectively, in the low cylinder group and from -7.78 ± 1.21 D to -4.6 ± 2.54 D, respectively, in the high cylinder group. By the last follow-up, 8.3% of patients had lost 2 lines of corrected distance visual acuity. There were no cases of corneal haze greater than 2+ or of graft rejection. Penetrating keratoplasty with adjunctive MMC decreased several refractive variables in patients with previous PKP. These results compare well with those in the published literature and suggest PRK is as effective as, and probably safer than, laser in situ keratomileusis in treating refractive error in these cases. No author has financial or proprietary interests in any material or method mentioned.

Salzmann’sche noduläre Degeneration 20 Jahre nach perforierender Keratoplastik bei Keratokonus

We report a unique case of a young patient who underwent penetrating keratoplasty for keratoconus 20 years previously and presented in our department with visual deterioration due to Salzmann's nodular degeneration (SND) on the corneal graft, induced probably by underlying recurrent herpetic (HSV) keratitis. The patient was treated with phototherapeutic keratectomy (PTK) and despite the low endothelial density of the corneal graft, visual acuity was sufficiently restored. Treatment with PTK is a promising therapeutic option in SND to avoid repeat penetrating keratoplasty, even if the prognosis for the corneal graft is endangered by several risk factors (age of the graft, low endothelial density, subclinical recurrent HSV infection).

Centre-Specific Variation in Corneal Transplant Outcomes in the United Kingdom

To examine the influence of center or surgeon transplant workload on corneal transplant outcome. In this database study, centers were categorized as high or low volume if registering more than 50 and less than 10 corneal transplants per year, respectively; surgeons were categorized as high or low volume if registering more than 30 and less than 10 transplants per year, respectively. The participants were patients aged at least 17 years receiving a first penetrating keratoplasty for keratoconus, Fuchs' endothelial disease, or pseudophakic corneal edema in a 7-year period from 1999 in (1) high-volume (n=1724) and low-volume (n=2131) centers and (2) under care of high-volume (n=1332) and low-volume (n=1949) surgeons. Main outcome measures were (1) graft survival at 5 years and (2) 2-year posttransplant best-corrected and day-to-day visual acuity and astigmatism. No significant difference in graft survival was found according to center or surgeon workload. Statistically significantly better day-to-day visual acuity was found only in patients with Fuchs' endothelial disease managed by high-volume surgeons (20/40 or better in 50% vs. 42% for low-volume surgeons). There was statistically significantly better best-corrected visual acuity in high-volume centers for Fuchs' endothelial disease and pseudophakic corneal edema and for high-volume surgeons in all disease groups. Based on this national transplant cohort, when analyzed according to center volume or surgeon transplant workload, there is no variation in graft survival and only minor variation in transplant functional outcome.