Penetrating Keratoplasty Group Research Articles

Recurrence Characteristics on Optical Coherence Tomography and Treatments of Reis-Bücklers Corneal Dystrophy After Phototherapeutic Keratectomy or Penetrating Keratoplasty

PurposeTo evaluate the recurrence characteristics on optical coherence tomography and clinical outcomes after phototherapeutic keratectomy (PTK) or penetrating keratoplasty (PKP) in patients with Reis-Bücklers corneal dystrophy (RBCD). DesignRetrospective interventional case series. MethodsSeventeen patients with RBCD (31 eyes, including six surgery-naïve eyes and 25 surgical eyes) received 44 surgical interventions from 1996 through 2022. PTK or PKP was performed as the initial surgical procedure. Significant recurrence was determined when best spectacle-corrected visual acuity decreased at least two lines with increased opacity in the superficial cornea. Repeated PTK or PTK on the corneal graft (CG-PTK) was considered if patients could not endure poor vision due to significant recurrence. Recurrence depth and annual increase in thickness of the central cornea and subepithelial deposits were assessed by anterior segment optical coherence tomography. ResultsThe mean follow-up time was 12.8±8.5 years (range, 2.0–25.5 years). The mean logMAR best spectacle-corrected visual acuity improved from 1.24±0.48 preoperatively to 0.27±0.09 postoperatively in the initial PTK group (13 eyes, P<0.001), from 1.84±0.69 to 0.40±0.13 in the PKP group (12 eyes, P<0.001), from 1.04±0.46 to 0.30±0.07 in the repeated PTK group (12 times in 7 eyes, P<0.001), and from 1.29±0.43 to 0.39±0.11 in the CG-PTK group (7 times in 5 eyes, P=0.001). The median significant recurrence time was 27 months (95% confidence interval 23.9-30.1), 96 months (84.1-107.9), 31 months (28.8-33.1), and 24 months (19.8-28.2), respectively (P<0.001). The depth of superficial deposits located between the epithelium and the anterior stroma was approximately 115μm (85-159μm). The annual thickening of subepithelial deposits was 14±2μm after initial PTK, 7±3μm after PKP, 14±3μm after repeated PTK, and 30±11μm after CG-PTK, compared to 4±2μm in surgery-naïve eyes (P=0.002, 0.515, 0.002, <0.001). The thickness of the central cornea increased by 15±2μm, 7±2μm, 15±3μm, and 31±10μm per year in the four surgery groups, respectively, compared to 5±2μm in surgery-naïve eyes (P=0.001, 0.469, 0.001, <0.001). ConclusionsBetter visual acuity can be achieved after PTK than PKP for treatment of RBCD. The annual thickening of subepithelial deposits may approximate an increase in central corneal thickness. The superficial distribution of subepithelial deposits makes it feasible to perform repeated PTK, even on the corneal allograft, for recurrent RBCD.

Comparison of therapeutic effects between big-bubble deep anterior lamellar keratoplasty and penetrating keratoplasty for medically unresponsive Acanthamoeba keratitis

PurposeTo compare the outcomes of big-bubble deep anterior lamellar keratoplasty (BB-DALK) and penetrating keratoplasty (PKP) in the management of medically unresponsive Acanthamoeba keratitis (AK).MethodsThis retrospective study included 27 eyes of BB-DALK and 24 eyes of PKP from a tertiary ophthalmology care centre. Glucocorticoid eye drops were subsequently added to the treatment plan 2 months postoperatively based on the evaluation using confocal laser scanning microscopy. The clinical presentations, best-corrected visual acuity (BCVA), postoperative refractive outcomes, graft survival, and Acanthamoeba recurrence were analyzed.ResultsThe AK patients included in the study were in stage 2 or stage 3, and the percentage of patients in stage 3 was higher in the PKP group (P = 0.003). Clinical presentations were mainly corneal ulcers and ring infiltrates, and endothelial plaques, hypopyon, uveitis and glaucoma were more common in the PKP group (P = 0.007). The BCVA and the graft survival rate showed no statistically significant differences between the two groups at 1 year after surgery. However, 3 years postoperatively, the BCVA of 0.71 ± 0.64 logMAR, the graft survival rate of 89.5%, and the endothelial cell density of 1899 ± 125 cells per square millimeter in the BB-DALK group were significantly better than those of the PKP group (P = 0.010, 0.046, and 0.032, respectively). 3 eyes (11.1%) in the BB-DALK group and 2 eyes (8.3%) in the PKP group experienced Acanthamoeba recurrence, but the rates showed no statistically significant difference between the two groups (P = 1.000). In the PKP group, immune rejection and elevated intraocular pressure were observed in 5 and 6 eyes, respectively.ConclusionCorneal transplantation is recommended for AK patients unresponsive to antiamoebic agents. The visual acuity and graft survival can be maintained after BB-DALK surgery. Acanthamoeba recurrence is not related to the surgical approach performed, whereas complete dissection of the infected corneal stroma and delayed prescribing of glucocorticoid eye drops were important to prevent recurrence.

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

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. 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. 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). 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.

Glaucoma after penetrating keratoplasty and keratoprosthesis

To compare visual and glaucoma outcomes in patients with known glaucoma after a penetrating keratoplasty (PKP) or a Boston Keratoprosthesis Type 1 (KPro) as a second corneal replacement procedure. Retrospective interventional case series. Charts of 141 eyes that underwent either a PKP or KPro at the Centre hospitalier de l'Université de Montréal after one failed PKP from 2008 to 2020 were reviewed. Forty-six eyes with preoperative glaucoma were included. Data collected included demographics, indication for the initial surgery, best corrected visual acuity (BCVA), concurrent ocular disorders, number of glaucoma medications, need for glaucoma surgery, cup-to-disc ratios (CDRs), mean RNFL thickness, and visual field (VF) characteristics. Primary outcomes were glaucoma progression trends. Secondary outcomes were visual outcomes and need for additional procedures. Mean follow-up was 4.7years for the PKP and 7.3 for the KPro group (P<0.007). 30.6% of PKP compared to 70.5% of KPro patients were diagnosed with glaucoma preoperatively. Glaucoma worsened similarly in both groups; this is based on an analysis of the number of glaucoma medications, CDR, need for glaucoma surgery, and characteristic VF changes. Patients in the PKP group required significantly more regrafts than patients in the KPro group (31.8 vs. 8.3%; P=0.045). A preoperative diagnosis of glaucoma does not preclude KPro implantation. In glaucomatous eyes, the disease progressed similarly in both groups. Since both procedures increase the risk of worsening glaucoma, close follow-up is recommended. KPro may decrease the need for further corneal transplantation surgery.

Comparison of Five-Year Graft Survival After Keratoplasty in the Veteran Population

Purpose: We investigated the corneal graft survival rate after penetrating keratoplasty (PK) and Descemet stripping endothelial keratoplasty (DSEK) in a veteran population. Methods: A retrospective review was conducted on patients undergoing a primary PK or DSEK at a large Veterans Affairs Medical Center between January 2005 and August 2019. Exclusion criteria included patients with a postoperative follow-up less than 5 years and patients undergoing additional ocular procedures during surgery. Patients were classified into 3 groups depending on their glaucoma status before corneal transplant: no pre-existing glaucoma, medically managed glaucoma, or surgically managed glaucoma. Graft survival was calculated using the Kaplan–Meier survival analysis. Results: A total of 30 eyes underwent PK, and 28 eyes underwent DSEK. There was no significant difference in graft survival rates between PK and DSEK at 1 year (83% vs. 79%, P = 0.555), 3 years (53% vs. 64%, P = 0.536), and 5 years (40% vs. 54%, P = 0.399). When combining PK and DSEK groups, Kaplan–Meier analysis showed a highly significant difference in 5-year graft survival between patients without pre-existing glaucoma (58%) and patients with either medically (50%) or surgically managed glaucoma (0%). Conclusions: We find approximate parity in 1-year, 3-year, and 5-year survival rates after PK and DSEK within the veteran population. However, survival rates for both procedures are lower than those previously reported within other populations. Additional studies to understand these differences in larger cohorts are warranted. Ophthalmologists must understand the increased risk of graft failure in the veteran population to provide appropriate counseling.

The role of corneal endothelium in macular corneal dystrophy development and recurrence.

Macular corneal dystrophy (MCD) is a progressive, bilateral stromal dystrophic disease that arises from mutations in carbohydrate sulfotransferase 6 (CHST6). Corneal transplantation is the ultimate therapeutic solution for MCD patients. Unfortunately, postoperative recurrence remains a significant challenge. We conducted a retrospective review of a clinical cohort comprising 102 MCD patients with 124 eyes that underwent either penetrating keratoplasty (PKP) or deep anterior lamellar keratoplasty (DALK). Our results revealed that the recurrence rate was nearly three times higher in the DALK group (39.13%, 9/23 eyes) compared with the PKP group (10.89%, 11/101 eyes), suggesting that surgical replacement of the corneal endothelium for treating MCD is advisable to prevent postoperative recurrence. Our experimental data confirmed the robust mRNA and protein expression of CHST6 in human corneal endothelium and the rodent homolog CHST5 in mouse endothelium. Selective knockdown of wild-type Chst5 in mouse corneal endothelium (ACsiChst5), but not in the corneal stroma, induced experimental MCD with similar extracellular matrix synthesis impairments and corneal thinning as observed in MCD patients. Mice carrying Chst5 point mutation also recapitulated clinical phenotypes of MCD, along with corneal endothelial abnormalities. Intracameral injection of wild-type Chst5 rescued the corneal impairments in ACsiChst5 mice and retarded the disease progression in Chst5 mutant mice. Overall, our study provides new mechanistic insights and therapeutic approaches for MCD treatment by high-lighting the role of corneal endothelium in MCD development.

Effect of Nd:YAG laser capsulotomy on graft endothelium after penetrating keratoplasty

BackgroundTo investigate the safety of Nd:YAG laser capsulotomy in eyes with Penetrating Keratoplasty (PK) and its impact on corneal endothelium as well as graft survival. MethodsThirty patients who underwent Nd: YAG laser capsulotomy after PK and 30 pseudophakic control eyes were included in this prospective study. Endothelial cell density (ECD), hexagonality (HEX), coefficient of variation (CV), central corneal thickness (CCT), and the change of these values during follow-up measured at the 1st hour, first week, and first month after the laser and the data were compared between groups. ResultsThe mean time passed between the PK procedure and the subsequent YAG laser procedure was i.e. of YAG laser after PK was 30.5 ± 15.2 months (range 6 to 57 months). Baseline ECD was 1648.2 ± 669.77 cells/mm² in the PK group and 2008.27 ± 347.42 cells/mm² in the control group. In the first month, ECD was 1545.2 ± 639.35 cells/mm² in the PK group and 1979 ± 350.95 in the control group. The loss was significantly higher in PK group (-103 ± 153.67 cells/mm²) (6.25%) compare to the control group (-28.73 ± 82.31 cells/mm²) (1.44%) (p = 0.024). A significant increase in CV was observed in the PK group, and not in the control group (p = 0.008, p = 0.255, respectively). There were no significant changes in HEX and CCT values in either group. ConclusionNd:YAG laser provides a significant increase in visual acuity in first month in patients with PK with no significant harmful effect on graft transparency. Endothelial cell density measurements during follow-up will be beneficial.

Comparison of penetrating keratoplasty versus lamellar keratoplasty for macular corneal dystrophy: a retrospective study of a single-center experience

Background: Although penetrating keratoplasty (PK) still remains the dominant form of transplantation for macular corneal dystrophy (MCD) patients, many studies evaluating these new forms of selective lamellar keratoplasty (LK) now suggest equivalent or better visual outcomes. This study aimed to explore the difference in outcomes and complications that follows each type of these operations. Methods: A retrospective, single-center study was performed at King Abdulaziz medical city in 2022. The study included patients with a histological diagnosis of MCD who undergone either PK or LK. Data was collected from health records using a form that consisted of patient characteristic, type of operation and post-operative outcomes, including visual acuity, survival rate and complications. Results: The study included a total of 54 eyes of patients who have MCD. A best corrected visual acuity (BCVA) of 0.5 or better was achieved in 82.5% of eyes of PK group and 42.9% of eyes of LK group. Graft survival rate was 90% (36 eyes) and 85.7% (12 eyes) in PK and LK groups respectively. Regarding complications, four PK eyes (10%) and one LK eye (7.1%) had high intraocular pressure, three PK eyes (7.5%) and one LK eye (7.1%) developed rejection, one PK eye (2.5%) developed recurrent epithelial erosion, and another one PK eye (2.5%) developed Traumatic epithelial laceration. Conclusions: PK operations resulted in a better post-operative visual acuity compared to LK group. The graft survival rate was slightly better for the PK group. PK was associated with higher incidence of complications than LK group.

Different Course of Immune Reactions and Endothelial Cell Loss after Penetrating Low-Risk Keratoplasty and Descemet Membrane Endothelial Keratoplasty for Fuchs Endothelial Dystrophy.

The aim of this study was to compare the incidence of immune reactions and endothelial cell loss after penetrating keratoplasty (PKP) vs. Descemet membrane endothelial keratoplasty (DMEK) in patients with Fuchs endothelial dystrophy (FED). In the present retrospective study, a total of 962 surgeries (225 excimer laser PKP and 727 DMEK) of 700 patients performed between 28.06.2007 and 27.08.2020 in the Department of Ophthalmology at Saarland University Medical Center UKS were statistically evaluated. On the one hand, the prevalence and the temporal course of the immune reactions that occurred were analysed using the Kaplan-Meier method, as well as the effect of the immune reactions on the endothelial cells and corneal thickness. Secondly, endothelial cell density, pleomorphism, and polymegethism of the endothelial cells were evaluated for the time points U1 = preoperative, U2 = 6 weeks postoperative, U3 = 6 to 9months postoperative, U4 = 1 to 2 years postoperative, and U5 = 5 years postoperative. In addition, statistical tests were carried out for differences between the two types of surgery and in the longitudinal course. A total of 54 immune reactions occurred during the observed period, whereby the probability of such a reaction was significantly greater in the PKP group with 8.9% than in the DMEK group with 4.5% (p = 0.011). The comparison of the two Kaplan-Meier curves also showed a significant difference between the two surgical techniques in the log-rank test (p = 0.012). The endothelial cell loss due to the immune reaction was only significant in PKP (p = 0.003). For all surgical procedures, endothelial cell density decreased significantly with time in both surgical techniques (p < 0.0001 in each case), but more strongly with DMEK than with PKP (p < 0.0001). Furthermore, this cell density was significantly higher with PKP than with DMEK for the whole observation time (p < 0.0001). Polymegethism decreased significantly in the DMEK group (p < 0.0001). Pleomorphism was significantly higher, on average, in DMEK than in PKP (p < 0.0001). The prognosis of DMEK in patients with FED seems to be more favourable after immune reactions than that of PKP, as not only were immune reactions less frequent, but they were also milder. However, endothelial cell density was significantly higher in the PKP group during the entire follow-up.

Penetrating Keratoplasty Versus Deep Anterior Lamellar Keratoplasty for Advanced Stage of Keratoconus

To compare visual acuity, refractive error, and complications after penetrating keratoplasty (PK) versus deep anterior lamellar keratoplasty (DALK) in the management of advanced stage of keratoconus. Retrospective, comparative, interventional study. This study enrolled 411 consecutive keratoconus eyes with preoperative mean keratometry ≥60 D that received either PK (218 eyes) or DALK (193 eyes). The outcome measures were postoperative visual acuity, refraction, complications, and further surgical interventions. The mean follow-up duration was 77.9±46.5 and 72.9±47.8 months in the PK and DALK groups, respectively (P=0.28). Compared to baseline values, postoperative visual acuity and refraction significantly improved in both groups. Postoperative corrected distance visual acuity was 0.18±0.13 and 0.26±0.19 logMAR in the PK and DALK groups, respectively (P<0.001). Postoperative spherical equivalent refraction was -2.89±2.89 D after PK and -4.58±3.62 D after DALK (P<0.001). Final keratometric astigmatism was comparable between the two groups (P=0.82). Suture-related complications were observed in 48.6% of the PK eyes and 72.0% of the DALK eyes (P<0.001). The incidence of graft rejection was 33.5% after PK and 19.7% after DALK (P=0.002). At the last visit, 98.2% of PK grafts and 94.8% of DALK grafts remained clear (P=0.06). Both techniques of corneal transplantation led to a significant improvement in the visual and refractive variables in eyes with advanced keratoconus. PK resulted in a better visual acuity and refraction with less suture-related complications compared to DALK. However, PK was associated with higher rate of graft rejection. The two techniques were comparable in terms of graft survival.

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

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). 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. 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. 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.

The clinical outcomes of keratoplasty in irreversible corneal decompensation secondary to Axenfeld-Rieger syndrome.

To evaluate the clinical outcomes of penetrating keratoplasty (PK) and Descemet's stripping automated endothelial keratoplasty (DSAEK) in eyes with irreversible corneal decompensation secondary to Axenfeld-Rieger syndrome (ARS). In this retrospective case series, a total of four eyes undergoing PK and seven eyes undergoing DSAEK, including one eye requiring one repeat DSAEK, between 2014 and 2021 were enrolled. Postoperative complications, graft survival, glaucoma treatment before and after keratoplasty, visual outcomes, and endothelial cell density were recorded. The mean follow-up duration was 34.4 ± 16.8months. Before keratoplasty, the mean BCVA was 2.0 ± 0.4 LogMAR, and the mean IOP was 21.7 ± 8.1mmHg. A total of 63.6% of eyes (7/11) received glaucoma treatment, including five eyes with glaucoma surgeries. After keratoplasty, 27.3% of eyes (3/11) exhibited secondary graft failure. The mean BCVA reached a maximum of 0.7 ± 0.5 LogMAR at 8.9 ± 7.5months, with no significant difference between the PK and DSAEK groups (P1 = 1.00, P2 = 0.12). Four eyes with previous glaucoma surgeries exhibited markedly high IOP. A total of 72.7% of eyes (8/11) required additional glaucoma treatments. The mean endothelial cell loss (ECL) rates at 1, 6, 12 and 24months were 43%, 49%, 63% and 54%, respectively, with no significant difference between the PK and DSAEK groups (P1 = 0.64, P2 = 1.00, P3 = 0.57, and P4 = 0.44). Both PK and DSAEK can successfully treat corneal decompensation secondary to ARS, resulting in similar outcomes with regard to IOP control, BCVA and ECL. IOP control is essential for postoperative management, especially for eyes with previous glaucoma surgeries.

Corneal biomechanical changes after Descemet stripping automated endothelial keratoplasty, penetrating keratoplasty, and phacoemulsification.

To evaluate corneal biomechanical changes after Descemet stripping automated endothelial keratoplasty (DSAEK), penetrating keratoplasty (PK), and phacoemulsification (PE). This prospective study included 138 eyes which underwent PK (26 eyes), DSAEK (26 eyes), PE (57 eyes), and 29 normal eyes. Intraocular pressure (IOP) was measured by Goldmann applanation tonometer (GAT), and central corneal thickness (CCT) and axial length by ultrasound. The ocular response analyzer was used to measure corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-related IOP (IOPg), and cornea-compensated IOP (IOPcc) preoperatively and 1, 3, and 6months postoperatively. At baseline, PK group had the lowest CH and CRF. There was a significant increase in CH and CRF to normal values in PK (P = 0.015 and 0.006) and PE (P = 0.005 and 0.0001) groups over the study period. At 6months, CH and CRF increased and reached normal values in the PK group; increased to a lower level than normal in the DSAEK group; and, after an initial reduction, increased to normal values in the PE group. At 6months, DSAEK group had the lowest CH and CRF. There was a significant positive correlation between CRF and GAT (r = 0.281, P = 0.009), IOPg and GAT (r = 0.335, P = 0.001), and IOPcc and GAT (r = 0.282, P = 0.001). CH was negatively correlated with age (r = -0.189, P = 0.04). Corneal biomechanical factors increase after DSAEK and PK. At post-operative month six, they reach normal values in PK group, but are lower than normal in DSAEK group.

Presence of Panel-reactive Antibodies after Penetrating Keratoplasty

ABSTRACT Purpose To evaluate the relationship between penetrating keratoplasty (PK) and postoperative PRA level and number of unacceptable antigens. Methods A cross-sectionalstudy was performed on patients with history of PK. Patients with prior solid organ transplantation, pregnancy, or blood transfusion were excluded. These findings were combined with a retrospective review. Patients were grouped by single or multiple PKs. The primary outcome was postoperative PRA level. Results Incidence of postoperative PRA elevation and mean peak PRA was higher in the multiple PK group (p = .08 and p = .010, respectively). Mean number of unacceptable antigens was elevated in the multiple PK group (p = .024). There was a moderately positive correlation between number of PK grafts and PRA level (r = 0.629, p = .0002). Conclusions PRA level may be influenced by PKs, with higher PRA associated with increased prior PKs. Further studies are necessary to determine the potential prognostic value. Abbreviations: PK: penetrating keratoplasty; PRA: panel reactive antibodies; OSST: ocular surface stem cell transplantation; LSCD: limbal stem cell deficiency

Outcomes of deep anterior lamellar keratoplasty and penetrating keratoplasty in keratoconic eyes with and without previous hydrops.

The study aims to compare outcomes after deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in keratoconic eyes with or without previous hydrops. Retrospective analysis of 211 eyes who received PK (group 1, n = 74 [history of hydrops: n = 33]) or DALK (group 2, n = 137 [history of hydrops: n = 9]) from 2012 to 2019 at the Department of Ophthalmology, University of Cologne, Germany. Analysis included best spectacle-corrected visual acuity (BSCVA), complications, immune reactions, graft survival and keratometry, and subgroup analyses for subjects with or without previous hydrops. Follow-up was 34.0 ± 23.6months in group 1 and 30.7 ± 22.5months in group 2. No significant difference was found in the course of BSCVA between groups 1 and 2 (p = 0.182) and in postoperative BSCVA between eyes with and without previous hydrops, regardless of the surgical method (p = 0.768). Endothelial immune reactions occurred exclusively in group 1 and did not occur more frequently in eyes with previous hydrops (p = 0.377). A higher risk of complications for eyes with previous hydrops was observed (p = 0.022). There was no difference in astigmatism and maximum keratometry (Kmax) preoperatively and postoperatively between eyes with and without history of hydrops. The prognosis for visual outcome after keratoplasty including visual acuity, astigmatism, and Kmax for keratoconic eyes with previous hydrops is as good as for keratoconic eyes without previous hydrops, irrespective of the surgical method. However, eyes after hydrops seem to have an increased risk of complications.

Surgical management of glaucoma following different keratoplasty techniques.

To investigate the results of surgical management of glaucoma following different keratoplasty techniques. Medical records of 628 cases who underwent keratoplasty were reviewed. One hundred and eighty-eight patients (29.9%) who developed post-keratoplasty glaucoma were evaluated. Patients who could not be controlled with maximal medical treatment and underwent glaucoma surgery were included in this study. Trabeculectomy, Ahmed glaucoma valve (AGV) implantation or diode laser cyclophotocoagulation (DLC) were applied. Glaucoma surgery was performed in 55 (29.3%) patients who had uncontrolled post-keratoplasty glaucoma. In penetrating keratoplasty group (n = 42), DLC was applied to 30 (71.4%) eyes, AGV to 11 (26.2%) eyes, and trabeculectomy in 1 (2.4%) eye. InDescemet'smembrane endothelial keratoplasty group (n = 8), DLC was applied to 4 (50%) eyes, trabeculectomy for 3 (37.5%) eyes and AGV for 1 (12.5%) eye. In deep anterior lamellar keratoplasty group (n = 5), DLC was applied to 2 (40%) eyes, trabeculectomy to 2 (40%) eyes and AGV to 1 (20%) eye. While a statistically significant decrease was found in intraocular pressure (IOP) and anti-glaucomatous medication after surgery (p < 0.05 for each), no significant difference was found in best corrected visual acuity (BCVA). During follow-up, DLC was applied as re-glaucoma surgery in 19 (34.5%) cases. A significant reduction in IOP together with number of anti-glaucomatous medications was found with re-operation; however, a significant decrease in BCVA was noted (p < 0.05 for each). Glaucoma surgeries after keratoplasty are effective in decreasing IOP and the number of anti-glaucomatous medication. While BCVA doesn't change after the first glaucoma surgery, after re-operation significant decrease may occur.

Comparison of Penetrating Keratoplasty and Descemet Stripping Automated Endothelial Keratoplasty in Eyes with Glaucoma Ahmed Valve implants

Purpose: To compare the clinical outcomes of penetrating keratoplasty (PKP) and Descemet stripping automated endothelial keratoplasty (DSAEK) in eyes with Glaucoma Ahmed Valve implants.Methods: The charts of 11 patients who underwent PKP and 11 who underwent DSAEK between February 2016 and June 2018 were retrospectively reviewed; all patients previously underwent Ahmed valve implant surgery. The best corrected visual acuity, intraocular pressure, and endothelial cell count were compared 1, 3, and 6 months after surgery. Graft rejection and graft failure were also evaluated during follow-up. The survival rates were compared using Kaplan–Meier survival analysis.Results: The difference in graft survival rates of the PKP and DSAEK groups was not significant (p = 0.295); however, graft failure occurred earlier in the PKP group (12.9 ± 10.1 vs. 18.8 ± 5.3 months). The postoperative best corrected visual acuity of the PKP group had improved at 1 (p = 0.027) and 3 (p = 0.017) months, while the DSAEK group showed significant improvement at 1, 3, and 6 months (all p = 0.005). Intergroup analysis showed better visual prognosis of the DSAEK group at 1, 3, and 6 months after surgery (p = 0.023, p = 0.007, and p = 0.004, respectively).Conclusions: In our study, the two corneal transplantation methods did not have significantly different graft survival rates; however, graft failure occured later in the DSAEK group and the postoperative visual acuity was better than in the PKP group. Although further study is needed, performing DSAEK in patients with an Ahmed valve implant seems to be a good alternative to PKP.

Boston type I keratoprosthesis versus penetrating keratoplasty following a single failed corneal graft.

To compare long-term outcomes of the Boston type 1 keratoprosthesis (KPro) with penetrating keratoplasty (PKP) in patients with a failed first PKP. In this retrospective comparative case series, 48 eyes of 48 patients who underwent a second corneal replacement procedure after a first failed PKP at the Centre Hospitalier de l'Université de Montréal from 2008 to 2020 were included. Minimum follow-up duration was 5 years, and patients with keratoconus were excluded since such subjects are not candidates for KPro. Main outcome measures included best-corrected visual acuity (BCVA), postoperative complications, graft survival and subsequent interventions. Mean follow-up was 6.4 years for PKP and 9.6 years for KPro (p < 0.001). Preoperative BCVA was better in PKP patients (means 1.67 vs 2.13, p = 0.041). Visual outcomes were similar between groups. KPro patients developed 0.263 complication per patient-year (ppy) compared to 0.245 ppy or PKP. The most common complications for PKP were corneal complications (0.088 ppy) and glaucoma worsening (0.041 ppy). In KPro, glaucoma worsening (0.046 ppy), vitreoretinal complications (0.042 ppy) and retroprosthetic membrane (0.042 ppy) were the most frequent. Graft failure (69.6 vs 20.0%, p < 0.001) and reoperation rates (56.5 vs 12.0%, p = 0.001) were significantly higher for PKP. Failure mainly resulted from decompensation or rejection in PKP, while all five failures in KPro were caused by melt and/or extrusion. Both interventions showed similar visual outcomes. Complication profiles were different, with more posterior segment complications in the KPro group, and more corneal complications in the PKP group, often necessitating regraft.

Penetrating Keratoplasty versus Deep Anterior Lamellar Keratoplasty for Keratoconus: A Systematic Review and Meta-analysis.

Keratoconus is the most common form of primary corneal thinning. Different methods have been suggested to deal with the condition, including glasses, contact lenses, and surgical interventions, like penetrating keratoplasty (PKP) and deep anterior lamellar keratoplasty (DALK), well-known methods of the latter. This study was conducted to compare the outcomes and side effects of the two mentioned keratoplasty techniques. First, we systematically reviewed all original articles studies on PubMed, Scopus, Web of Science, and Embase. Then, the extracted data were pooled and meta-analyzed on each of the intended outcomes. A total of 30 studies were included in which PKP was more commonly performed compared to DALK. We found that adverse outcomes consisting of cataracts, graft rejection, graft failure, High-IOP, and corneal infection, were all more common findings in the PKP groups compared to the DALK groups. However, only for the high-IOP, cataracts, and graft rejection, the analysis of the extracted results demonstrated statistical significance. Overall, the DALK groups demonstrated significantly better results when considering the improvement levels by measuring the Endothelial Cell Count (ECC) and Spherical Equivalent (SE). In addition, though statistically insignificant, the Central Corneal Thickness(CCT), Best Corrected Visual Acuity(BCVA), Topographic Cylinder(TC), Refractive Cylinder values were greater in the PKP groups. Based on our study and with its limitations in mind, we can conclude that DALK can be a relatively safer and more effective procedure. Though, a larger number of high-standard randomized clinical trials still need to be conveyed for more definite conclusions.

Deep anterior lamellar keratoplasty versus penetrating keratoplasty: comparison of clinical outcomes in contralateral eyes.

This study aimed to compare the clinical outcomes following deep anterior lamellar keratoplasty and penetrating keratoplasty in contralateral eyes of the same patients. In this retrospective, comparative case series, clinical outcome data included best-corrected visual acuity, refractive spherical equivalent, refractive astigmatism, endothelial cell density, endothelial cell loss, central corneal thickness, and intraocular pressure, which were evaluated at 6, 12, 24, and 36 months after deep anterior lamellar keratoplasty and penetrating keratoplasty. Additionally, complications were assessed. Fifty-two eyes (26 patients) were included, of which 19 patients had keratoconus, 6 had stromal dystrophy, and 1 had post-laser-assisted in situ keratomileusis ectasia. The mean follow-up was 44.1 ± 10.5 months in the deep anterior lamellar keratoplasty Group and 47.9 ± 11.9 months in the penetrating keratoplasty Group. No significant differences were observed in the mean best-corrected visual acuity, refractive spherical equivalent, refractive astigmatism, and central corneal thickness between the deep anterior lamellar keratoplasty and penetrating keratoplasty Groups during follow-up. The endothelial cell density was significantly higher in the deep anterior lamellar keratoplasty Group than in the penetrating keratoplasty Group at 24 and 36 months postoperatively (p=0.022 and 0.013, respectively). Endothelial cell loss was significantly lower in the deep anterior lamellar keratoplasty Group than in the penetrating keratoplasty Group at 24 and 36 months postoperatively (p=0.025 and 0.001, respectively). Intraocular pressure was significantly lower in the deep anterior lamellar keratoplasty Group than in the penetrating keratoplasty Grroup at 6 months postoperatively (p=0.015). Microperforation occurred in 4 eyes (15%) during deep anterior lamellar keratoplasty surgery; however, penetrating keratoplasty was not required. No endothelial rejection occurred in the penetrating keratoplasty Group during follow-up. Over the 3-year follow-up, endothelial cell loss and intraocular pressure in the deep anterior lamellar keratoplasty Group were significantly lower than those in the penetrating keratoplasty Group, while visual and refractive results were similar.