Femtosecond thin-flap laser assisted in situ keratomileusis for correction of post-penetrating keratoplasty ametropia: long-term outcome

PURPOSE

To evaluate the long-term clinical outcomes of femtosecond thin-flap LASIK (femto-LASIK) for correction of refractive error after penetrating keratoplasty in keratoconus-affected eyes.

SETTING

a private ophthalmology clinic.

DESIGN

Prospective interventional case series.

METHODS

This prospective interventional case series enrolled 22 eyes of 22 patients who underwent femto-LASIK for the management of post-penetrating keratoplasty ametropia. The refractive error, uncorrected (UDVA), and corrected (CDVA) distance visual acuities and vector analysis were reported in short-term and long-term period after surgery.

RESULTS

The mean age was 32.7 ± 7.5 years (range, 23 to 47 years) at the surgery time. The average time between PK and femto-LASIK was 42.5 ± 31.7 months. The average follow-up duration after femto-LASIK was 81.2 ± 18.6 months. The mean preoperative UDVA significantly improved from 0.47 ± 0.15 logMAR to 0.35 ± 0.14 logMAR at 12 months (P = 0.048) and 0.4 ± 0.17 at final follow-up exam (P = 0.007). CDVA was 0.22 ± 0.1 at baseline which improved to 0.18 ± 0.15 and 0.15 ± 0.1 logMAR at 12 and 81 months, respectively. (Ps = 0.027, 0.014). The mean cylinder before surgery was - 5.04 ± 1.4D which significantly decreased to -1.5 ± 0.8 D at 12 months postoperatively. (P < 0.001). There was a significant increase in refractive astigmatism from 12 months to 81 months postoperatively (-3.1 ± 2.0, P = 0.002). At the final visit, the efficacy index was 0.83, and the safety index was 1.16.

CONCLUSIONS

Despite the short-term outcome indicated that femo-LASIK was effective for correction of post-keratoplasty ametropia during short-term period, a notable regression in its effect was observed in the long-term follow-up. Therefore, the predictability of this technique might decrease in the long-term.

Influence of Post-radiation Ocular Surface Disorder on Ocular Surgery: A Case Report and Review of the Literature

BACKGROUND

Ocular surface disorder after ocular radiation therapy, even though commonly reported, is often overlooked. Any delay in diagnosis may lead to complications that threaten vision. The presented case highlights the clinical outcome of a severe post-radiation disorder of the ocular surface, the importance of intensive therapy, and the limitations of further surgical interventions.

CASE PRESENTATION

A 34-year-old woman was referred for a second opinion due to a years-long history of pain and redness in her right eye (OD) after proton beam therapy for recurrent iris melanoma. The patient then developed post-radiation retinopathy with macula edema, secondary glaucoma, cataract, as well as a severe ocular surface disorder with corneal decompensation and band keratopathy. Several surgical treatments have been attempted, including phacoemulsification with IOL implantation and trabeculectomy with mitomycin C. Due to refractory glaucoma, Baerveldt glaucoma drainage was then necessary. Given the worsening clinical presentation of post-radiation ocular surface disorder with progressing band keratopathy, the possibility of penetrating keratoplasty (PKP) was discussed.

CONCLUSION

The continuous worsening of clinical symptoms of the disorder of the ocular surface after proton beam radiotherapy can be the result of a post-radiation syndrome. Gradual expansion of ischemia, vasculitis, and inflammatory mediators compresses the retinal tissue, leading to recurrent macular edema as well as to secondary glaucoma and corneal decompensation. Band keratopathy is occasionally noted and seems to result from severe post-radiation disorder of the ocular surface. However, PKP would typically be indicated in cases of corneal perforation, uncontrolled infectious keratitis, or for improving vision in the presence of corneal opacification, none of which applied to our patient. Furthermore, post-radiation keratopathy implies compromised corneal stromal lymphogenesis and angiogenesis, both of which are now considered essential conditions for allograft rejection. Moreover, a previously performed Baerveldt glaucoma drainage surgery can affect the survival rate of the endothelial cells of the recipient cornea. Therefore, a penetrating or endothelial keratoplasty should be viewed as a high-risk procedure. In this instance, the rigorous treatment of the severe ocular surface disorder was crucial. We managed our patient's complex situation by following the latest guidelines set by the Tear Film & Ocular Surface Society and aimed to alleviate the symptoms as effectively as possible. In conclusion, careful decision-making regarding surgical treatment options should be considered, taking into account the complexities and potential risks involved.

Infectious Keratitis After Keratoplasty in the United States: Analysis of a National Medicare Claims Data Set

PURPOSE

The aim of this study was to assess the incidence, trends, and risk factors of infectious keratitis (IK) and subsequent repeat keratoplasty after penetrating keratoplasty (PK) and endothelial keratoplasty (EK).

METHODS

Using a retrospective cohort study design, IK cases within 6 months of keratoplasty were identified using billing codes among 100% Medicare beneficiaries aged 65 years and older who underwent either PK or EK between 2011 and 2020. Multivariable logistic regression models were used to evaluate factors associated with postkeratoplasty IK.

RESULTS

We identified 115,588 keratoplasties, of which 20.0% (n = 23,144) were PK and 80.0% (n = 92,444) were EK. IK developed within 6 months with a rate of 3.32% (n = 769) post-PK and 0.72% (n = 666) post-EK. Overall rates of IK decreased from 16.05 to 9.61 per 1000 keratoplasties between 2011 and 2020 ( P < 0.001). The median interval between keratoplasty and diagnosis of IK was 73 days (interquartile range: 29-114 days) for PK and 74 days (interquartile range: 38-116 days) for EK. After IK, 22.9% (n = 176) and 23.8% (n = 159) eyes underwent repeat keratoplasty within 1 year for PK and EK, respectively. The occurrence of IK after PK was associated with age 85 years and older [odds ratio (OR): 1.38; 95% confidence interval (CI): 1.13-1.68] relative to patients aged 65 to 74 years. The occurrence of IK after EK was also associated with age 85 years and older (OR: 1.44; 95% CI: 1.14-1.82) relative to patients aged 65 to 74 years.

CONCLUSIONS

IK was 4 times more common after PK than EK and the complication was associated with older age. Our findings may help corneal surgeons in counseling patients at higher risk and guiding their postoperative care.

Suture-related complications after deep anterior lamellar keratoplasty for keratoconus

PURPOSE

The purpose of this study is to determine the incidence of suture-related complications, their risk factors, and effects on the clinical outcomes after deep anterior lamellar keratoplasty (DALK) for keratoconus.

METHODS

In this retrospective, comparative, interventional study, the records of consecutive patients with keratoconus who underwent DALK were reviewed for suture-related complications. Univariate analyses were used to identify risk factors for suture complications. We compared groups with and without suture-related complications to evaluate the effects of these complications on clinical outcomes after DALK.

RESULTS

Of the 633 DALKs, 438 eyes (69.2%) developed suture complications including loose sutures (32.7%), spontaneous suture rupture (30%), sterile suture abscesses (22.8%), suture tract vascularization (16.4%), suture erosion (10.3%), and suture cheese wiring (6.8%). Vernal keratoconjunctivitis increased the incidence of sterile suture infiltration, premature suture loosening, and suture tract vascularization. Loose suture was observed more commonly in larger graft size, while spontaneous suture rupture was associated with late suture removal. There was no statistically significant difference in postoperative outcomes including visual acuity, refraction, graft rejection, and failure in eyes with and without suture complications. However, suture-related complications were directly associated with sight-threatening ocular morbidities, including graft rejection (39 eyes), ulcer (1 eye), and failure (2 eyes).

CONCLUSION

Suture-related complications frequently occurred after DALK for keratoconus. Ocular surface inflammation, large grafts, and late suture removal increased the risk of suture-related complications. While these complications had no negative impact on clinical outcomes in the majority of cases, some of them led to sight-threatening morbidity, underlining the importance of early diagnosis and treatment.

Glaucoma after penetrating keratoplasty and keratoprosthesis

PURPOSE

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.

DESIGN

Retrospective interventional case series.

PARTICIPANTS

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.

METHODS

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.

RESULTS

Mean follow-up was 4.7 years 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).

CONCLUSIONS

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.

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

PURPOSES

This study aims to assess and compare the postoperative visual and topographic outcomes, complications, and graft survival rates following deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with macular corneal dystrophy.

METHODS

In this study we enrolled 59 patients (23 male; and 36 female) with macular corneal dystrophy comprising 81 eyes. Out of these, 64 eyes underwent penetrating keratoplasty, while 17 eyes underwent deep anterior lamellar keratoplasty. The two groups were analyzed and compared based on best-corrected visual acuity, corneal tomography parameters, pachymetry, complication rates, and graft survival rates.

RESULTS

After 12 months, 70.6% of the patients who underwent deep anterior lamellar keratoplasty (DALK) and 75% of those who had penetrating keratoplasty (PK) achieved a best-corrected visual acuity of 20/40 or better (p=0.712). Following surgery, DALK group showed lower front Kmean (p=0.037), and Q values (p<0.01) compared to the PK group. Postoperative interface opacity was observed in seven eyes (41.2%) in the DALK group. Other topography values and other complications (graft rejection, graft failure, cataract, glaucoma, microbial keratitis, optic atrophy) did not show significant differences between the two groups. The need for regrafting was 9.4% and 11.8% in the PK and DALK groups, respectively (p=0.769). Graft survival rates were 87.5% and 88.2% for PK and DALK; respectively (p=0.88 by Log-rank test).

CONCLUSION

Both PK and DALK are equally effective in treating macular corneal dystrophy, showing similar visual, topographic, and survival outcomes. Although interface opacity occurs more frequently after DALK the visual results were comparable in both groups. Therefore, DALK emerges as a viable surgical choice for patients with macular corneal dystrophy without Descemet membrane involvement is absent.

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

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

[Analysis of long-term outcomes of penetrating keratoplasty for congenital corneal opacity]

Objective: To investigate the long-term outcomes of corneal grafts after penetrating keratoplasty(PK) for congenital corneal opacity(CCO) in children aged 0 to 5 years and the related influencing factors. Methods: It was a retrospective series case study. Data of 39 children (55 eyes) who underwent PK surgery due to CCO in the keratology Department of Beijing Tongren Hospital from April 2014 to April 2018 and were followed up for more than 30 months were collected. Among them, there were 17 males (43.6%) and 22 females (56.4%). The age at operation was (16.2±13.3) months, and the follow-up time was (46.4±13.8) months. Clinical data such as basic information, preoperative diagnosis, operation age, operation method and postoperative complications were recorded. The corneal graft transparency was analyzed according to preoperative diagnosis, corneal neovascularization area, age at surgery, monocular or binocular surgery interval, primary surgery type and further surgery, and postoperative complications were observed. Results: At 12 months, 24 months and the last follow-up after PK, 78.2% (43/55), 70.9% (39/55) and 58.2% (32/55) of the affected eyes had clear corneal grafts, respectively.There was no statistical significance between Peters anomaly and sclerocornea (P>0.05), while the extent of neovascularization in the limbus had a significant effect on corneal graft transparency, and graft opacity was more likely to occur in patients with vessel area exceeding 2 quadrants (P<0.05).The highest corneal graft transparency was found in children aged 1 to 3 years 80.8%(21/26) (P<0.05), followed by children younger than 6 months (7/15).The translucency rate of the corneal graft was higher in patients undergoing unilateral surgery than in those undergoing bilateral surgery (P<0.05).Translucency of corneal graft was higher in children with simple surgery than with combined surgery (P<0.05), however, cataract surgery after PK had no significant effect on corneal graft transparency (P>0.05).The postoperative complications mainly included immune rejection in 19 eyes (34.5%), complicated cataract in 13 eyes (23.6%), glaucoma in 7 eyes (13.2%), persistent corneal epithelial defect in 7 eyes (13.2%). Conclusions: After PK in children with CCO, the transparent rate of corneal grafts decreases gradually with time, but the long-term translucency of corneal grafts can still be obtained. The range of corneal neovascularization, age at the time of surgery, whether the surgery was binocular and whether the surgery was combined had an effect on the transparency of corneal graft.

High Astigmatism Secondary to Peripheral Ectasia Recurrence in Postpenetrating Keratoplasty Eyes Managed With Miniscleral Contact Lenses

OBJECTIVES

After penetrating keratoplasty (PK) for keratoconus, vision can be impaired by high-degree astigmatism, particularly in those patients with recurrent peripheral ectasia. Scleral contact lenses (CLs) have long been used in the management of keratoconus both in treatment-naive corneas and those postcorneal transplants. We report the use of miniscleral CLs and their related visual and clinical outcomes in a series of patients with post-PK peripheral rim ectasia.

METHODS

In this retrospective case series, 5 patients (7 eyes) presented because of reduced visual acuity with their spectacles/CLs and/or reduced comfort with their existing rigid gas-permeable lenses. All patients in this series underwent PK more than two decades ago for keratoconus (mean 28.7 years±7.2). All patients demonstrated characteristic thinning at the graft-host junction, with anterior chamber deepening. Central corneas had remained clear in all patients inferring high visual potential. Contact lenses used were No 7 Comfort 15 miniscleral and the Onefit MED scleral with 14.5 mm and 15.6 mm diameters, respectively.

RESULTS

All eyes achieved a best-corrected visual acuity of 6/9 or greater. One case had difficulty with insertion and removal and has since discontinued wearing lens at this time. All others are successfully wearing the lenses regularly.

CONCLUSION

Despite advances in CL design, surgical management is still required in some patients. Miniscleral CLs are effective in the refractive management of peripheral ectasia in keratoconic post-PK eyes and should be considered in such eyes before proceeding with repeat surgical intervention.

Cataract surgery following penetrating keratoplasty in children

Background

Following penetrating keratoplasty, cataract surgery warrants certain modifications to ensure maximum survival of the graft.

Purpose

To emphasize the intraoperative challenges and surgical manipulations to be followed.

Synopsis

The surgeon makes a superior sclerocorneal tunnel avoiding the graft host junction. Dispersive viscoelastic is used. Continuous curvilinear capsulorhexis is done. Cataractous lens aspirated with a low flow rate. The intraocular lens is placed in the bag. Superior peripheral iridectomy and primary posterior capsulorhexis are done. The wound closed with two interrupted 10-0 nylon sutures. Graft host junction integrity is maintained.

Highlights

Ensure 1. Good intraoperative corneal visibility, 2. Avoid graft host junction for main port incision 3. Generous dispersive viscoelastic use/soft shell technique to protect the corneal endothelium, 4. Avoid phaco energy in case of soft cataracts/low phaco energy and flow rates, 5. Phaco probe to be meticulously oriented away from corneal endothelium, 6. Primary posterior capsulorhexis to be done as in any pediatric cataract surgery, 7. Make sure of the graft host junction integrity at the end of the surgery, 8. Restrict to a single port whenever possible.

Video link

https://youtu.be/tu4R5JangYs.

Recurrent Filamentous Fungal Keratitis Caused When the Primarily Selected Graft Diameter was Too Small

PURPOSE

To establish the importance of using a sufficiently large corneal graft in primary penetrating keratoplasty in order to prevent recurrence of fungal keratitis.

OBERSERVATIONS

A 58-year-old female patient underwent emergency penetrating keratoplasty (diameter 7.0 mm, double running suture) for therapy-resistant fungal keratitis (Fusarium solani) at an external eye clinic. Despite intensive antifungal therapy, new fungal infiltrates appeared in the host cornea after a few days. The patient was referred to our department for further treatment. On first presentation, circular infiltrates were seen around the corneal graft with anterior chamber involvement and therapy-resistant hypopyon. We performed an emergency penetrating repeat keratoplasty (diameter of 13.0 mm, 32 interrupted sutures) combined with anterior chamber lavage and intracameral and intrastromal drug injection.

CONCLUSION AND IMPORTANCE

Fungal keratitis sometimes has a frustrating clinical course. Therefore, early diagnosis with effective therapy initiation is of the utmost importance. In cases of penetrating keratoplasty, optimal planning and timing (before anterior chamber involvement) should be provided. Sufficient safety distance must be ensured in the choice of graft diameter, fixation with multiple interrupted sutures, and anterior chamber lavage, as well as intracameral and intrastromal drug administration. Incomplete excision carries a risk of recurrence and endophthalmitis in the course. Close postoperative control is necessary to detect early recurrences.

Hallermann-Streiff Syndrome in Concordant Monozygotic Twins With Congenital Cataracts, Exudative Retinal Detachments, and One Case of Corneal Perforation Requiring Keratoplasty

PURPOSE

We describe the management of Hallermann-Streiff syndrome in monozygotic female twins with congenital cataracts, exudative retinal detachments, and 1 case of corneal descemetocele with associated dellen and subsequent perforation.

METHODS

This study was a case report and review of the literature.

RESULTS

Twins 1 and 2 exhibited all 7 cardinal characteristics of Hallermann-Streiff syndrome, presenting with spontaneous lenticular resorption, anterior uveitis, and glaucoma. They underwent bilateral cataract extraction with near total capsulectomy. Both twins experienced recurrent glaucoma, for which twin 1 underwent successful endocyclophotocoagulation in both eyes and twin 2 in the left eye alone. The fellow eye developed 2 sites of perilimbal corneal descemetoceles with associated dellen at the inferotemporal limbal corneal junction leading to spontaneous perforation of 1 site, requiring a full-thickness corneal graft. Both twins developed recurrent bilateral exudative retinal detachments unresponsive to oral prednisolone. Twin 1's last best-corrected visual acuity with aphakic spectacles was 20/260 in the right eye and 20/130 in the left eye at age 4 years and 8 months. Twin 2's last best-corrected visual acuity was 20/130 in each eye at age 4 years and 11 months, over a year after right eye penetrating keratoplasty.

CONCLUSIONS

We describe 2 rare cases of Hallermann-Streiff syndrome in monozygotic twins complicated by corneal perforation requiring penetrating keratoplasty in 1 eye of 1 twin. Although corneal opacities have been described in this condition, this is the first case of corneal descemetocele in Hallermann-Streiff syndrome. The cornea was stabilized with a relatively favorable visual outcome over 1 year later.

Incidence and risk factors for glaucoma development and progression after corneal transplantation

OBJECTIVE

To assess the cumulative incidence and risk factors for glaucoma development and progression within 1-2 years following corneal transplant surgery.

DESIGN

Retrospective cohort study.

METHODS

Patients undergoing penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), Descemet stripping endothelial keratoplasty (DSEK), Descemet membrane endothelial keratoplasty (DMEK), Boston keratoprosthesis type I (KPro) implantation, or endothelial keratoplasty (DSEK or DMEK) under previous PK (EK under previous PK) at one academic institution with at least 1 year of follow-up were included. Primary outcome measures were cumulative incidence of glaucoma development and progression after corneal transplant, in patients without and with preoperative glaucoma, respectively. Risk factors for glaucoma development and progression were also assessed.

RESULTS

Four hundred and thirty-one eyes of 431 patients undergoing PK (113), DALK (17), DSEK (71), DMEK (168), KPro (35) and EK under previous PK (27) with a mean follow-up of 22.9 months were analyzed. The 1-year cumulative incidence for glaucoma development and progression was 28.0% and 17.8% in patients without and with preoperative glaucoma, respectively. In a Cox proportional hazards analysis, DSEK surgery, KPro implantation, average intraocular pressure (IOP) through follow-up and postoperative IOP spikes of ≥30 mmHg were each independently associated with glaucoma development or progression (p < 0.04 for all).

CONCLUSIONS

A significant proportion of patients developed glaucoma or exhibited glaucoma progression within 1 year after corneal transplantation. Patient selection for DSEK may partly explain the higher risk for glaucoma in these patients. Postoperative IOP spikes should be minimized and may indicate the need for co-management with a glaucoma specialist.

Long-Term Endothelial Cell Viability After Deep Anterior Lamellar Versus Penetrating Keratoplasty for Keratoconus

OBJECTIVES

We compared long-term endothelial cell survival after penetrating versus after deep anterior lamellar keratoplasty for keratoconus.

MATERIALS AND METHODS

We retrospectively compared 64 eyes of 55 patients who had penetrating keratoplasty and 40 eyes of 37 patients who had deep anterior lamellar keratoplasty for keratoconus (October 2003-February 2021). Best-corrected visual acuity, Goldmann applanation tonometry, fundus examination with 90D lens, and specular microscopy with CEM-530 (Nidek) were performed preoperatively and every 6 months postoperatively. Main outcomes were endothelial cell density, central corneal thickness, and visual acuity. Secondary outcomes were coefficient of variation, hexagonality, graft rejection episodes, and graft clarity.

RESULTS

We found no significant differences between the 2 treatment groups regarding patient age, donor age, preoperative vision, central corneal thickness, and recipient-donor trephine diameters. Mean follow-up was 92.5 months. In deep anterior lamellar keratoplasty, the endothelium was preserved significantly better for 10 years versus for penetrating keratoplasty. Mean endothelial density in penetrating versus deep anterior lamellar keratoplasty was 2006.7 versus 2354.7 cells/mm2 at 1 year (P = .010), 1170.5 versus 2048.2 at 5 years (P <.001), and 972.5 versus 1831.6 at 10 years (P < .001). Cumulative endothelial cell loss was 43% and 19.7% at 10 years for penetrating and anterior lamellar keratoplasty, respectively. Significantly more thickening of central cornea was shown in penetrating keratoplasty after 7 years. Corneal thickness was 583.0 µm in penetrating and 545.1 µm in deep anterior lamellar keratoplasty (P = .002) at 10 years. Vision gain and coefficient of variation were similar. Hexagonality decreased significantly in both groups at 10 years. Rates of rejection were 12.5% in penetrating and 7.5% in deep anterior lamellar keratoplasty. Graft survival rates were 97.5% and 96.9%, respectively.

CONCLUSIONS

In keratoconus, endothelial vitality is better preserved with deep anterior lamellar keratoplasty than with penetrating keratoplasty over a 10-year follow-up.

Laser in situ keratomileusis versus Artisan lens implantation in correcting ametropia after penetrating keratoplasty for keratoconus

PURPOSE

To compare the long-term safety and efficacy of laser in situ keratomileusis (LASIK) with Artisan phakic intraocular lens implantation to correct refractive errors after penetrating keratoplasty (PK) for keratoconus.

METHODS

This retrospective comparative interventional case series included a total of 33 consecutive keratoconus eyes that had previous PK and received subsequent LASIK (n = 16) or Artisan lens implantation (n = 17) were included in this study. Outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refractive error, and complications.

RESULTS

Postoperatively, the UDVA of ≥20/40 was achieved in none of the LASIK group compared to 62.5% of eyes in the Artisan group (P < 0.001); the respective values for CDVA of ≥20/40 were 87.5 and 94.1% (P = 0.51). Spherical equivalent refraction decreased from - 6.97 ± 1.50 D preoperatively to - 4.20 ± 2.05 D postoperatively in the LASIK group (P < 0.001) and from - 10.79 ± 2.15 D preoperatively to - 2.13 ± 1.23 D postoperatively in the Artisan group (P < 0.001). There was no significant change in the refractive astigmatism in LASIK group (P = 0.30) or Artisan group (P = 0.11). The efficacy and safety indices were significantly better for Artisan (0.82 ± 0.34 and 1.13 ± 0.30, respectively) than for LASIK (0.22 ± 0.17 and 0.85 ± 0.24, respectively, P ≤ 0.006 for both comparisons). While refractive error changed significantly from postoperative year 3 to the final visit in the LASIK group, it remained stable in the Artisan group through follow-up period. No significant complications were observed in any group.

CONCLUSION

Artisan lens implantation provided superior and stable visual outcomes compared to LASIK for the management of post PK refractive errors in keratoconus eyes.

[Surgical technique of keratoplasty with simultaneous implantation of a continuous ring or ring segment into the graft]

The article presents the surgical technique of penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK) with femtosecond-laser assistance involving simultaneous implantation of an intracorneal continuous ring (ICCR) or an intracorneal ring segment (ICRS) into the graft. Surgical technique no. 1 - keratoplasty with simultaneous implantation of ICRS. Intrastromal circular tunnel is formed in the central zone of donor cornea using femtosecond laser. Then penetrating trepanation 8.1 mm in diameter is performed symmetrically to the formed tunnel. After preparing penetrating or lamellar recipient bed, suture fixation is placed in the corneal transplant, then the ICRS is implanted into the graft. Surgical technique no. 2 - keratoplasty with simultaneous implantation of ICCR. The donor cornea is dissected from periphery to center using femtosecond laser. Central zone remains untouched. A large diameter full-thickness trepanation is performed and the donor cornea is divided into the anterior and posterior layers. The ICCR is put on the donor cornea while holding the posterior layer with forceps. Penetrating or lamellar recipient bed is prepared, then the corneal graft is fixed with sutures. Transparent corneal graft acceptance does not guarantee high visual acuity due to post-keratoplasty astigmatism. Surgical correction of astigmatism is performed in the long term post-operatively and isn't effective enough. We proposed this new surgical technique of keratoplasty with simultaneous implantation of ICCR and ICRS into the graft as close as possible to the visual axis of the eye, which can help make the postoperative astigmatism minimal both immediately after surgery and in the long term. The study proposes a new approach to intraoperative prevention of post-keratoplasty astigmatism. The technique is simple, safe and effective. Analysis of long-term outcomes is required before recommending this method for widespread use in clinical practice.

Outcomes of Penetrating Keratoplasty After Open Globe Injury

PURPOSE

The purpose of this study was to investigate the clinical features, surgical outcomes, and prognostic factors of penetrating keratoplasty (PKP) after open globe injury (OGI).

METHODS

A retrospective review of all patients treated for OGI between January 2000 and July 2017 was conducted. Demographic, preoperative, perioperative, and postoperative data were collected for those who underwent PKP after OGI. The predictive value of each preoperative variable on graft failure was assessed using univariate and multivariable Cox proportional hazards models, and the predictive value of variables on post-PKP visual outcome was assessed using both univariate and multivariable logistic regression models. All eyes that underwent PKP after OGI were included unless they had less than 365 days of follow-up.

RESULTS

Forty-six eyes that underwent PKP met inclusion criteria. The median age was 46 years (interquartile range = 23.00-61.25), median follow-up was 78.5 months (interquartile range = 38.63-122.02), and 37 of 46 subjects (80.4%) were male. The observed 1- and 5-year graft survival estimates were 80.4% and 41.7%, respectively. Factors statistically associated with graft failure in multivariable analyses were rejection episode, hazard ratio (HR) = 3.29; retinal detachment (RD), HR = 3.47; and endophthalmitis, HR = 6.27. Fifteen of 42 eyes (35.7%) regained ambulatory vision (20/200 or better). The strongest predictors of vision worse than 20/200 at the last follow-up were RD, odds ratio (OR) = 43.88; graft rejection, OR = 12.42; and injury outside the workplace, OR = 25.05.

CONCLUSIONS

Despite a high graft survival at 1 year, most of the patients did not regain ambulatory vision. Graft rejection, RD, and endophthalmitis were risk factors for graft failure. These factors should be considered when counseling patients regarding PKP after OGI.

Enterobacter cloacae Keratitis: Clinicomicrobiological Profiles, Risk Factors, and Outcomes

PURPOSE

The purpose of the study was to report the clinical features, risk factors, antibiotic susceptibility, and treatment outcomes in a series of Enterobacter cloacae keratitis.

METHODS

A retrospective analysis was performed of the electronic medical records of microbial keratitis caused by E. cloacae identified by the Vitek 2 system (BioMerieux, Craponne, France). We collected data pertaining to demographics, risk factors, ulcer characteristics, antibiogram, visual acuity at presentation and final follow-up, and management outcome. The main outcome measure was resolution of infection. The final visual acuity was the secondary outcome measure.

RESULTS

Ten episodes of E. cloacae keratitis in 9 patients were identified between January 2009 and December 2019. Nine (90%) cases had undergone penetrating keratoplasty and 8 were failed grafts. Other risk factors included topical steroid use and irregular ocular surface due to epithelial bullae. The mean ulcer size was 17.55 ± 13.99 mm 2 . More than 80% of isolates were sensitive to chloramphenicol, gentamicin, and colistin. Nine (90%) cases healed on medical management within 56.55 ± 26.74 days (range 9-120 d), although almost all required adjunctive procedures: tissue adhesive application (n = 6) and/or tarsorrhaphy (n = 4). One case with a near total infiltrate had a mixed infection with Kocuria kristinae requiring therapeutic penetrating keratoplasty. One case developed endophthalmitis and phthisis after the corneal infiltrate resolved.

CONCLUSIONS

E. cloacae keratitis is a rare clinical entity seen more often in immunocompromised host conditions such as failed corneal transplants with concomitant topical steroids. Most cases healed with medical management.

Acute corneal allograft rejection following SARS-CoV-2 vaccination-A systematic review

All documented cases of acute corneal allograft rejection following SARS-CoV-2 vaccination were examined, to characterize possible risk factors and graft outcomes. Comprehensive search (4 electronic databases: PubMed, CENTRAL, ClinicalTrials.gov, Google Scholar, plus manual search in articles' reference lists) until March 1st 2022 to identify studies reporting acute corneal allograft rejection following SARS-CoV-2 vaccination; study protocol was developed in line with PRISMA statement. We analysed demographics, allograft type, rejection prophylaxis regime at the time of vaccination, transplantation-to-vaccination time (G-Vt), vaccination-to-immune reaction onset time (V-Rt), management, best-corrected visual acuity before and after rejection, and graft survival. Of 169 titles/abstracts screened, 16 studies (n  = 36 eyes) met the inclusion criteria. Fourteen eyes (38.9%) had received >1 graft, and 11.1% of cases had history of immune reactions; 52.9% of cases occurred after the first dose. Median (P25-P75) G-Vt was 48 (10-78) months; median V-Rt was 9 (7-14) days. In eyes with resolved rejection, median time-to-resolution was 3 (1-4) weeks. Four eyes (11.1%) had partial resolution of corneal decompensation, and 5 grafts (13.9%) failed. Acute corneal allograft rejection after SARS-CoV-2 vaccination is a rare event, but may occur any time post-keratoplasty. Early recognition and prompt, aggressive treatment is warranted to optimize vision and graft survival. Well-known risk factors for rejection may be confounding factors, including the high proportion of cases with a history of previous grafts and the rejection prophylaxis regimes at the time of vaccination. Increasing immunosuppressants in the peri-vaccination period may decrease the risk of immune reactions, especially in high-risk cases.

Blast Wound Dehiscence During Descemet Membrane Endothelial Keratoplasty Rebubbling in a Previous Penetrating Keratoplasty: A Case Report

PURPOSE

The purpose of this study was to describe a rare complication of Descemet membrane endothelial keratoplasty (DMEK) rebubbling.

METHODS

An 86-year-old woman with bilateral penetrating keratoplasty (PK) performed 20 years previously for Fuchs endothelial dystrophy underwent DMEK surgery for endothelial corneal decompensation in the left eye. Surgery was complicated in the postoperative period by repeated DMEK graft detachments requiring rebubbling.

RESULTS

The third rebubbling procedure caused a traumatic PK wound dehiscence at the graft-host junction with full-thickness opening of approximately 180 degrees. PK wound dehiscence was resutured in the theater, DMEK lenticule was removed from the eye, and the full-thickness graft was repeated.

CONCLUSIONS

DMEK graft rebubbling in patients with previous PK may lead to traumatic wound dehiscence. Avoidance of excessive increases in intraocular pressure during the rebubbling procedure should be encouraged to decrease the risk of this rare complication.

Reticular epithelial edema after penetrating keratoplasty in a patient taking netarsudil

Netarsudil is a relatively new medication for the treatment of primary open-angle glaucoma and ocular hypertension. It has been associated with red eyes and burning after instillation. Reticular epitheliopathy is a relatively rare complication of netarsudil that has been described in patients with preexisting corneal edema. We report the case of a healthy 76-year-old woman who developed reticular epitheliopathy after full-thickness penetrating keratoplasty that completely resolved following discontinuation of the medication. In cases where netarsudil is initiated for treatment of glaucoma or, off-label, endothelial dysfunction, reticular epithelial edema should be considered in patients complaining of a decline in vision and severe pain.

[Clinical analysis of penetrating keratoplasty for infants with congenital corneal opacity]

Objective: To investigate the corneal graft survival and related risk factors of primary penetrating keratoplasty in congenital corneal opacity infants. Methods: It was a retrospective cohort study. Data were collected from forty-two infants (51 eyes) who were aged ≤12 months and diagnosed with congenital corneal opacity in Beijing Tongren Hospital and Beijing Anzhen Hospital from January 1, 2017 to January 31, 2018. The mean age at surgery was (5.7±2.2) months (3-12 months). The mean follow-up duration was (28.6±2.6) months (24-33 months). All the patients underwent penetrating keratoplasty. The status of the corneal grafts and complications were observed and recorded during the regular follow-up. The survival probabilities were estimated by using the Kaplan-Meier and Log-rank test. The graft survival between different influence factors was analyzed by using the χ² test. Results: The Kaplan-Meier survival rates for penetrating keratoplasty were 84.3% (43/51) at 6 months, 78.4% (40/51) at 12 months and 60.8% (31/51) at the last follow-up. The presence of corneal neovascularization was significantly correlated with graft failure (χ²=5.264, P=0.022). The graft survival differed between eyes receiving combined surgery and mere penetrating keratoplasty and in eyes with varied surgical indications (P=0.039, <0.01). Increased intraocular pressure (7 eyes, 13.7%) and persistent epithelial defects (7 eyes, 13.7%) were the most common postoperative complications, followed by complicated cataract (4 eyes, 7.8%) and posterior capsule opacification (2 eyes, 3.9%). Conclusions: The graft survival rate was satisfactory following pediatric keratoplasty although it had a tendency to decrease with the follow-up time. Corneal neovascularization was a major risk factor of graft failure. Surgical indications and procedures also had a certain effect on the graft survival.

P-15 Utilising endothelial migration to perform deep anterior lamellar keratoplasty in eyes with deep posterior corneal scarring typically treated with penetrating keratoplasty

*Correspondence - Luis García-Onrubia: luis.garciaonrubia@gstt.nhs.uk PURPOSE: To describe a novel technique for deep anterior lamellar keratoplasty (DALK) in patients central corneal perforation and deep scarring making conventional DALK (Melles or Big Bubble) unviable. A posterior Descemet's membrane (DM) skirt has provided an adequate scaffold for the migration of the host endothelial cells.

METHODS AND ANALYSIS

A case report. A 32-year-old male with previous hydrops developed severe corneal scarring with a break in DM visible on OCT scanning. A modified DALK procedure was perform consisting of a 400µm, 8.5mm Anterior lamellar cap with a 4.5mm posterior lamellar disc, denuded of endothelial cells and containing a DM skirt.Initially, manual dissection of the and anterior 400µm of corneal stroma was performed using a modified Melles technique. The residual posterior lamellar was assessed and found to have significant residual scarring. A central 4mm optical window was performed through the posterior lamellar over the visual axis.The donor tissue was cut using a 350µm microkeratome head. The anterior cap was trephined to 8.5mm and set aside. The posterior lamellar was placed in a punch block, and the endothelial was removed using a silicone tipped cannula. The removal of endothelial cells was confirmed using trypan blue dye. A posterior lamellar graft with a 4.0mm stromal bed and a 4.5mm DM skirt was fashion using a peeling and double punch technique. The posterior lamellar graft was inserted into the optical window such that the DM skirt provided a bridge to the donor corneal endothelium. The anterior cap was sutured with a double continuous suture of 10-0 monofilament nylon. An inferior peripheral iridotomy was created, and an air bubble filling the anterior chamber was left at the end of the case.

RESULTS

The preoperative visual acuity (VA) was hand movements. Full attachment of the posterior lamellar was seen at all time-points from week one onwards. Central corneal pachymetry continued to reduce for 12 weeks. One year after the operation, with sutures in, the best spectacle-corrected VA was 6/12. The corneal graft was clear, and no rejection episodes occurred. Endothelial cell repopulation of the donor DM could be observed with specular microscopy.

CONCLUSION

The presence of DM promotes endothelial migration and healing. Modifications to traditional DALK surgery, in which DM is used to promote endothelial healing, are a viable alternative to penetrating keratoplasty. This method eliminates the risk of allograft endothelial rejection and allows a 'regenerative' for DALK to be used, offering a new modality of treatment in patients with healthy reserves of endothelial cells and deep posterior lamellar scarring.

P-12 A case of Descemet's membrane detachment following penetrating keratoplasty for keratoconus

*Correspondence - Nadeem Ahmad: nadeem.ahmad123@doctors.org.uk OBJECTIVE: To present an uncommon case of Descemet's (DM) detachment 20 years following PK for keratoconus. The detachment spontaneously resolved with conservative management.To review the literature and published case reports for the clinical course, prognosis, and managements employed for DM detachment following PK.

METHODS AND ANALYSIS

Case presentation of a patient presenting to our department and review of the literature.

RESULTS

Our patient presented with a spontaneous DM detachment 20 years after an uncomplicated PK for keratoconus. Imaging showed recurrence of corneal ectasia inferiorly, which would give this patient a poorer prognosis and higher risk of re-detachment after surgical intervention for the detachment. We opted for conservative management, after which the DM detachment spontaneously resolved and corneal thickness improved.DM detachment is an uncommon late complication of PK and pathophysiology is thought to be mechanical due to a retrocorneal membrane, or due to recurrence of corneal ectasia. The majority of published cases underwent surgery with air, SF6, or C3F8 with postoperative supine positioning, or progression to repeat PK or DSAEK if this initial treatment fails. Topical steroids can be given for conservative management.

CONCLUSION

Conservative management of DM detachment can be an option for patients with guarded prognosis, or in small detachments with no tears. Our case provides another data point on the presentation and progression of this complication to the small number of case reports in the literature.

Microbial Keratitis Associated With Penetrating Keratoplasty and Scleral Lens Wear: A Case Series

OBJECTIVES

To report on microbial keratitis (MK) in three scleral lens (SL) wearers who had undergone penetrating keratoplasty (PKP).

METHODS

This retrospective case series describes 3 cases of MK in patients who wore SLs after PKP.

RESULTS

All three patients wore SLs for visual rehabilitation for corneal irregularity induced by PKP; all three also had concurrent ocular surface disease (keratoconjunctivitis sicca and corneal exposure). Cultures identified the causative organism in two patients, and septated hyphae suggestive of fungal infection were identified in tissue removed during therapeutic PKP in the third patient. All three patients were receiving either topical or systemic immunosuppressive therapy before the infection developed.

CONCLUSIONS

Scleral lenses are often used to manage complex ocular disease, which can make it difficult to determine the precise cause of complications that arise after wearing the lenses. Multiple factors, including SL wear, may have contributed to the initial development of MK in the three patients in this case series. Patients who wear SLs after PKP should be monitored closely.

Five Cases of Corneal Graft Rejection After Recent COVID-19 Vaccinations and a Review of the Literature

PURPOSE

The purpose of this study was to report 5 cases of acute corneal graft rejection after COVID-19 vaccination and perform a review of the literature.

METHODS

This was a case series and review of literature dated on the October 10, 2021.

RESULTS

We describe 5 cases-2 patients with Descemet stripping automated endothelial keratoplasty (for Fuchs endothelial dystrophy) who presented with acute corneal graft rejection after their first dose of mRNA (BNT162) vaccine. The other 3 patients who had penetrating keratoplasty performed more than 10 years ago for keratoconus presented with acute graft rejection-2 patients after their second dose of adenovirus vector (AZD1222) vaccine and 1 patient after first dose of mRNA (BNT162) vaccine. Three patients were not using any topical steroid treatment at the time of diagnosis of graft rejection. The mean duration between vaccination and onset of symptoms was 16.86 ± 6.96 days for the mRNA vaccine and 17 ± 11.89 days for the adenovirus vector vaccine.

CONCLUSIONS

Corneal graft rejection has recently been reported after COVID-19 vaccination. Patients with keratoplasty need to be advised regarding the risk of corneal graft rejection and warning symptoms of rejection after COVID-19 vaccination. Seeking early referral to the emergency department and increasing topical steroids pre-COVID-19 and post-COVID-19 vaccination may reduce the risk of rejection.

[Optical rehabilitation and pediatric ophthalmological care following keratoplasty for childhood corneal opacities]

BACKGROUND

The younger the children are at the time of corneal transplantation, the worse the survival prognosis of the graft.

PREOPERATIVE CONSIDERATIONS

Preoperative considerations are significant in terms of accurate parental education, ensuring adherence to treatment and choosing the appropriate surgical time frame (amblyopia versus graft failure, compliance of the patient). Parental education must include the reduced visual prognosis in young children, exceptions being later acquired corneal pathologies such as inflammatory corneal scars (herpes) and keratoconus.

POSTOPERATIVE CARE

A distinction must be made between morphological care after transplantation and refractive correction as well as treatment of amblyopia. The younger the children, the less favorable the prognosis for the transplant and the more often multiple examinations with anesthesia are necessary in order to detect complications, such as infiltrates or suture loosening at an early stage. Especially unilateral congenital pathologies often do not lead to a sufficient improvement of amblyopia (refractory amblyopia, poor compliance).

CONCLUSION

The prognosis after keratoplasty in childhood is already partly decided by the careful evaluation of indications (no surgery of a sclerocornea) and the detailed and realistic clarification for the parents (cooperation with long-term ocular and systemic treatment even if the child has poor compliance, frequent check-ups, reduced chances of amblyopia treatment). The younger the child is at the time of transplantation, the more frequent are graft failure and the development of complications. Later manifesting diseases in older children (herpetic corneal scars, keratoconus) have a better prognosis.

Analysis of risk factors of rapid attenuation of graft endothelium in the early stage after penetrating keratoplasty

This study aimed to analyze the factors of rapid attenuation of graft endothelium in the early stage after penetrating keratoplasty (PKP), with a view to guiding patients with PKP to better long-term outcomes. This study included 226 patients who underwent PKP with follow-up time >1 year at the Qingdao Eye Hospital of Shandong First Medical University from January 2018 to June 2020. Medical records were retrospectively studied, and donor factors, patient factors, and surgical factors were comparatively analyzed to clarify those affecting the rapid decay of graft endothelium after PKP. The median time between excision and death >60 min and patient age >60 years were risk factors for endothelial cell loss (ECL) rate >30% at 1 month postoperatively. However, a higher percentage of patients with donor age ≤60 years and Optisol preservation solution had endothelial cell density (ECD) >2000 cells/mm² in the graft at postoperative 1 year. A year after the surgery, patients with corneal endothelial decompensation and immune rejection were at risk for ECD < 1000 cells/mm². The combined operations had a significant effect on the ECL in the early postoperative period. Patients who underwent combined extracapsular cataract extraction or intraocular lens implantation had a significantly higher rate of ECL at postoperative 1 month than other patients, and no significant effect at postoperative 1 year. However, patients without combined operations have a higher probability of maintaining a high level of graft ECD. The graft diameter also affected postoperative ECL. In patients with a larger graft diameter, attenuation of ECD was slower. The ultimate goal of PKP is to maintain graft transparency for extended periods. The use of younger donors, minimizing unnecessary operation in the anterior chamber, and minimizing immune rejection may maintain a greater donor corneal endothelium in the long term.

[Optical properties of the cornea after different modifications of penetrating keratoplasty]

PURPOSE

Comparative analysis of optical properties of the cornea after different modifications of penetrating keratoplasty.

MATERIAL AND METHODS

The study included 56 patients (56 eyes) divided into three study groups according to the surgery technique. Group I included 17 patients (17 eyes) after one-piece mushroom keratoplasty, group II - 21 patients (21 eyes) after two-piece mushroom keratoplasty and group III - 18 patients (18 eyes) after penetrating keratoplasty. In addition to standard examination methods, before surgery and in the course of the follow-up all patients underwent software-powered corneal densitometry on the anterior segment analyzer (Pentacam HR, "Oculus", Germany), as well as an assessment of the degree and regularity of postoperative astigmatism.

RESULTS

Comparison of the obtained results revealed with a high degree of confidence higher values of the total specific light scattering after two-piece mushroom keratoplasty throughout the entire observation period (p<0.05). At the same time, there was no statistically significant difference in visual acuity between the three study groups (p>0.05). A statistically significant increase in the level of induced astigmatism was revealed after penetrating keratoplasty.

CONCLUSION

The observed increase in light scattering after two-piece mushroom keratoplasty does not lead to a decrease in visual acuity. The interface in the optical zone of the cornea formed by a microkeratome does not affect the degree and regularity of induced astigmatism.

[Comparative evaluation of the results of one- and two-piece mushroom keratoplasty]

PURPOSE

To compare and evaluate the outcomes of one- and two-piece mushroom keratoplasty configurations for various corneal pathologies.

MATERIAL AND METHODS

A total of 32 patients (32 eyes) with corneal perforations, descemetocele and deep corneal opacities underwent surgery. Depending on the surgery technique, the patients were divided into 2 groups: group I (17 eyes) underwent manual one-piece mushroom keratoplasty according to our own technique; group II (15 eyes) underwent modified two-piece microkeratome-assisted mushroom keratoplasty according to the technique by M. Busin. All patients underwent clinical and functional studies before surgery and in the course of a 1-year follow-up.

RESULTS

Transparent engraftment of the cornea was achieved in 82 and 80% of cases; best corrected visual acuity (BCVA) averaged 0.57±0.19 and 0.53±0.17; spherical component of refraction varied from 1.25 to +5.5 and from 1.25 to 6.0 diopters; mean corneal astigmatism was 3.15±1.73 and 3.21±1.89 diopters in groups I and II, respectively. At 6 months after surgery, the mean endothelial cell density (ECD) was 2336±198 and 2291±175 cells/mm², at 1 year - 2041±189 and 1955±161 cells/mm² in groups I and II, respectively.

CONCLUSION

One- and two-piece mushroom keratoplasty is effective in surgical treatment of various corneal pathologies ensuring a high rate of transparent corneal engraftment. The revealed risk of false chambers formation between separate parts of the graft after the two-piece method could in most cases be eliminated by re-injecting air into the anterior eye chamber.

Elevated Cytokine Levels in Aqueous Humor Are Associated with Peripheral Anterior Synechiae after Penetrating Keratoplasty

Peripheral anterior synechiae (PAS) after corneal transplantation leads to refractory glaucoma and permanent loss of vision. However, the exact mechanism remains elusive. This study aimed to evaluate the association between cytokine levels in the aqueous humor (AqH) and the progression of PAS after penetrating keratoplasty (PKP). We measured 20 cytokine levels in AqH and assessed the correlation with PAS progression after PKP in 85 consecutive patients who underwent PKP. We also evaluated age-dependent alterations in PAS and cytokine levels in DBA2J mice. PAS developed in 38 (44.7%) of 85 eyes after PKP. The incidence of intraocular pressure increase after PKP was significantly greater in eyes with PAS (26.3%) than in those without PAS (2%, p = 0.0009). The PAS area at 12 months after PKP was significantly positively correlated with the preoperative levels of interleukin (IL)-6, interferon (IFN)-γ and monocyte chemotactic protein (MCP)-1 (p ≤ 0.049). In the DBA2J mice, an experimental glaucoma model that developed PAS at 50 weeks, the AqH levels of IL-2, IL-6, IL-10, IFN-γ, tumor necrosis factor-α, MCP-1 and granulocyte-macrophage colony-stimulating factor (GM-CSF) significantly increased at 50 weeks compared to 8 weeks (p ≤ 0.021). In conclusion, inflammatory alterations in the AqH microenvironment, such as high preoperative specific cytokine levels, can lead to PAS formation and glaucoma.

Fulminant Sphingomonas paucimobilis keratitis: case study and review of literature

Sphingomonas paucimobilis is a low-virulence gram-negative bacillus known to cause various ocular infections such as endophthalmitis, panophthalmitis and keratitis that are usually associated with an underlying risk factor such as peri-partum or postpartum phase, cataract surgery, contact lens use, neurotrophic keratopathy or ocular trauma. We report a case of spontaneously occurring perforated corneal ulcer caused by the organism in a young man managed by penetrating keratoplasty. The course was followed by endophthalmitis with graft infection culminating in phthisis bulbi despite aggressive medical and surgical management. Along with reporting this case, we also present a review of literature on ocular infections caused by the same organism.

Factors Predictive of Double Anterior Chamber Formation Following Deep Anterior Lamellar Keratoplasty

PURPOSE

To identify risk factors predictive of postoperative double anterior chamber formation after deep anterior lamellar keratoplasty (DALK).

DESIGN

Retrospective institutional cohort study.

METHODS

The study group included all consecutive eyes undergoing primary DALK between May 2015 and October 2018 at Villa Igea private hospital (Forli, Italy). The indications for surgery were categorized as (1) keratoconus without scarring; (2) keratoconus with scarring; (3) non-keratoconus without scarring; and (4) non-keratoconus with scarring. Multivariate binary logistic regression analysis was performed, introducing, as independent variables, those that reached a significance level of less than .05 in univariate analysis. The main outcome measure was whether or not postoperative double anterior chamber (AC) occurred.

RESULTS

A total of 591 eyes of 591 patients were included. The main indication for DALK was keratoconus (67.2%, n = 397), and pneumatic dissection was achieved in 72.9% (n = 431) of patients. Postoperative double AC was observed in 8.1% (n = 48) of cases. Age, intraoperative central DM perforation, type 2 bubble formation, and presence of scar in keratoconic and nonkeratoconic corneas were all associated with an increased risk of postoperative double AC formation in the univariate analysis. Manual dissection was not associated with double AC formation. The factors that remained significant in multivariate analysis were keratoconus with scarring (odds ratio [OR] = 3.56, P = .02), non-keratoconus with scarring (OR = 5.09, P = .002), intraoperative central perforation (OR = 6.09, P = .03), and type 2 bubble formation (OR = 14.17, P < .001).

CONCLUSIONS

Scarred corneas of both normal and abnormal shape are independent risk factors for double AC formation following DALK, along with intraoperative perforation and the occurrence of a type 2 bubble.

Three-Dimensional Optical Coherence Tomography Imaging For Glaucoma Associated With Boston Keratoprosthesis Type I and II

PRECIS

Three-dimensional (3D) spectral domain optical coherence tomography (OCT) volume scans of the optic nerve head (ONH) and the peripapillary area are useful in the management of glaucoma in patients with a type I or II Boston Keratoprosthesis (KPro).

PURPOSE

The purpose of this study was to report the use of spectral domain OCT in the management of glaucoma in patients with a type I or II Boston KPro.

MATERIALS AND METHODS

This study is an observational case series. Four consecutive patients with KPro implants were referred for glaucoma evaluation. A comprehensive eye examination was performed which included disc photography, visual field testing, and high-density spectral domain OCT volume scans of the ONH and the peripapillary area. 2D and 3D parameters were calculated using custom-designed segmentation algorithms developed for glaucoma management.

RESULTS

Spectral domain OCT parameters provided useful information in the diagnosis and management of 4 KPro patients. OCT parameters which can be used in KPro patients included 2D retinal nerve fiber layer (RNFL) thickness, 3D peripapillary RNFL volume, 3D peripapillary retinal thickness and volume, 3D cup volume, and 3D neuroretinal rim thickness and volume. In 3 of 4 cases where the traditional 2D RNFL thickness scan was limited by artifacts, 3D spectral domain OCT volume scans provided useful quantitative objective measurements of the ONH and peripapillary region. Therefore, 3D parameters derived from high-density volume scans as well as radial scans of the ONH can be used to overcome the limitations and artifacts associated with 2D RNFL thickness scans.

CONCLUSIONS

Spectral domain OCT volume scans offer the possibility to enhance the evaluation of KPro patients with glaucoma by using both 2D and 3D diagnostic parameters that are easily obtained in a clinic setting.

Deep Intrastromal Arcuate Keratotomy With In Situ Keratomileusis (DIAKIK) for the Treatment of High Astigmatism After Keratoplasty: 2-Year Follow-up

PURPOSE

To describe 2-year results of deep intrastromal arcuate keratotomy with in situ keratomileusis (DIAKIK) for the treatment of high astigmatism after keratoplasty.

METHODS

This prospective study included 20 eyes from 20 patients presenting with high astigmatism after keratoplasty. All were treated by two-step femtosecond laser surgery, with two intrastromal arcuate keratotomies and a corneal flap, followed a few months later by excimer photoablation after reopening of the flap.

RESULTS

At 24 months, both uncorrected (UDVA) and corrected (CDVA) distance visual acuity had improved from 1.12 ± 0.42 logMAR (20/200 Snellen) before surgery to 0.58 ± 0.23 logMAR (20/80 Snellen) (P < .001) and from 0.31 ± 0.26 logMAR (20/40 Snellen) to 0.20 ± 0.20 logMAR (20/32 Snellen) (P = .04), respectively. The mean spherical equivalent improved from -5.01 ± 4.35 to -1.54 ± 2.42 diopters. The mean efficacy index was 0.63. The mean correction index was 0.93 ± 0.32. The mean flattening index was 1.09 ± 0.75 and the mean safety index was 1.39. No graft rejection or epithelial ingrowth was observed.

CONCLUSIONS

This two-step procedure was an effective treatment for high astigmatism after keratoplasty. The use of both femtosecond and excimer lasers helped to avoid some complications that would have jeopardized the grafts. Refractive and topographic stability was good 2 years after surgery. [J Refract Surg. 2019;35(4):239-246.].

Herpes simplex virus linear endotheliitis in a post-keratoplasty patient: A case report

RATIONALE

To report a case of herpes simplex virus (HSV) linear endotheliitis in a 57-year-old male who had underwent keratoplasty 10 years ago. The characteristic linear keratic precipitates (KPs) resembled the Khodadoust line in graft rejection. The differential diagnosis is essential, because the treatment regimen is different between HSV linear endotheliitis and graft rejection.

PATIENT CONCERNS

The patient developed a sudden onset of ocular pain and a decrease in visual acuity in his right eye. The patient had received penetrating keratoplasty in the eye 10 years ago.

DIAGNOSES

The ocular disease was evaluated using several ocular examinations, including best-corrected visual acuity (BCVA), intraocular pressure, slit lamp examination, fundus examination, and aqueous humor tap. Characteristic linear endothelial KPs were found both in the host cornea and graft cornea. Stromal edema was evident in both the donor and recipient corneas. The aqueous humor was sampled for viral polymerase chain reaction (PCR) analysis. The sample was investigated for the possible presence of HSV I, HSV II, cytomegalovirus, and varicella zoster virus. The PCR was positive for HSV I and negative for HSV II, cytomegalovirus, and varicella zoster virus.

INTERVENTIONS

The patient was treated with both antiviral and steroid treatments for 1 month. Thereafter, prophylactic antiviral treatment was continued.

OUTCOMES

The subjective symptoms had improved and the cornea edema and the linear endothelial KPs had disappeared. The BCVA improved from 20/200 to 20/80.

LESSONS

HSV linear endotheliitis is the most severe form of HSV endotheliitis. This case showed characteristic endothelial KPs, which were different from the Khodadoust line of graft rejection.

Outcome of deep anterior lamellar keratoplasty patients with intraoperative Descemet's membrane perforation: A retrospective cross-sectional study

PURPOSE

To evaluate functional and anatomical outcome in patients undergoing deep anterior lamellar keratoplasty (DALK) with intraoperative Descemet's membrane (DM) perforation (macro and micro).

METHODS

A retrospective cross sectional study (January 2009 to December 2015) of sixteen eyes of sixteen patients which included nine patients of advanced keratoconus (KC), two patients with paracentral DM scarring post hydrops, KC with Bowman's membrane scarring, macular corneal dystrophy and one patient of advanced Pellucid Marginal Degeneration (PMD). All underwent DALK with intraoperative DM perforation. Big bubble technique was attempted in all except in the two patients with post hydrops DM scar. Preoperative and postoperative best corrected visual acuity (BCVA), astigmatism and endothelial count (EC) were compared.

RESULTS

Postoperative BCVA and astigmatism were found to be better and statistically significant ('p value' 0.00 and 0.003 respectively). BCVA preoperative and postoperative was 1.07± 0.3 and 0.28 ± 0.09 in LogMAR respectively and astigmatism pre and postoperative 4.14 ± 1.5 D and 2.7 ± 0.97 D respectively. Percentage decrease in EC at sixth postoperative week was 7.48% and at sixth month and 1 year postoperative was 15.1%. Two patients developed postoperative double anterior chamber and two patients developed pupillary block glaucoma and all were successfully managed.

CONCLUSION

Not all patients of intraoperative DM perforation (including macro perforation) needs to be converted to penetrating keratoplasty. DALK can be successfully done if the perforation is identified early and managed adequately. This is the only known study which has shown a large series of successful DALK even with macro perforations.

Characteristics and risk factors of recurrent keratoconus over the long term after penetrating keratoplasty

PURPOSE

To determine the characteristics and risk factors of recurrent keratoconus (KC) after penetrating keratoplasty (PK).

METHODS

We enrolled patients who had maintained clear grafts for at least 10 years after PK based on their medical records. Patients were divided into the KC group or Others group based on the primary indication for PK. Each case was reviewed for clinically observed corneal ectasia. Steepest keratometric power (Ks), cylinder (CYL), and difference between Ks and minimum keratometric power (MinK) were analyzed in patients that underwent corneal topography more than three times after the 5th postoperative year.

RESULTS

One hundred one eyes of 82 patients were enrolled. The KC group comprised 50 eyes and the Others group comprised 51 eyes (herpes [n = 22], corneal leukoma [n = 12], and other [n = 17]). The mean period after PK was 27.2 years in the KC group and 26.0 years in the Others group. Recurrent KCs were observed in 18 eyes of 14 patients (36%), all of whom were in the KC group (p = 0.0001). Six of these eyes underwent PK again and all the grafts showed keratoconic changes histopathologically. The mean Ks during the whole observation period was 52.5 diopters (D) in the KC group and 49.2 D in the Others group (p < 0.0001). Logistic regression analysis revealed the risk factors of recurrent KC with positive Ks change and large CYL with significant p values (p = 0.0102, 0.0318, respectively).

CONCLUSIONS

KC progresses even after PK over the long term, requiring re-grafting in some cases. Risk factors for recurrent KC after PK are increasing Ks over time and a large CYL.

Management of Delayed Massive Suprachoroidal Hemorrhage: A Clinical Retrospective Study

Suprachoroidal hemorrhages, both expulsive and delayed non-expulsive, are among the most devastating complications of intraocular surgery. We reviewed the charts of 13 patients with a delayed non-expulsive suprachoroidal hemorrhage (DNSCH) after cataract extraction (3 patients), glaucoma filtering surgery (6 patients), penetrating keratoplasty (3 patients), or vitrectomy (1 patient). All had large hemorrhagic choroidal detachments with nine eyes presenting kissing choroidal detachment, five eyes with associated retinal detachment, and one eye with intravitreous hemorrhage. All patients were treated with systemic corticosteroids before surgery. Eleven eyes underwent anterior drainage sclerotomy, followed by SF6 gas injection in eight eyes, and pars plana vitrectomy with silicon oil tamponade in three eyes. Mean follow-up was 22 months. These procedures gave good anatomical results in eleven cases and good visual results in nine. The results suggest that not all DNSCH need to be drained surgically but that, when surgical drainage is indicated, the use of gas to maintain internal tamponade appears to be beneficial.

Assessment of visual evoked potentials in patients eligible for penetrating keratoplasty

Corneal opacities can obstruct ophthalmology examination in patients before penetrating keratoplasty (PK).To assess the usefulness of visual evoked potentials (VEPs) in estimating postoperative visual acuity (VA) in patients eligible for (PK) with opaque cornea in 1 eye and good VA in the fellow eye.In this observational study, the mean age of 52 males and 48 females was 57.17 ± 15.99 (21-87 years old). A total of 100 patients eligible for PK underwent an ophthalmological examination including VA and a VEP examination. The P2/P2 ratio was calculated. The correlation coefficient of the VA and the P2/P2 ratio was evaluated 1, 6, and 12 months after PK.A positive correlation of the P2/P2 ratio and VA 1, 6, and 12 months after PK were observed.VEPs including the P2/P2 ratio can be useful in estimating postoperative VA in patients eligible for PK.

Factors Affecting Changes in Astigmatism before and after Suture Removal following Penetrating Keratoplasty

PURPOSE

To analyze the factors related to changes in astigmatism before and after suture removal in patients who underwent penetrating keratoplasty (PK).

METHODS

The study group consisted of 171 consecutive PKs in 171 patients. Keratometric astigmatism was measured before and after suture removal in all patients. The vectorial difference for each eye was calculated between the examination before suture removal and the first year after suture removal. The vectorial difference values were compared with the possible factors affecting astigmatic change such as age of the patient, donor-recipient trephine diameter difference, preoperative diagnosis, and time of suture removal. All sutures were removed completely in one session. The vectorial difference values of all groups were compared with each other statistically.

RESULTS

Before suture removal, the mean cylinder was 4.40 +/- 3.24 D; it was 3.96 +/- 2.19 D at 1 year after suture removal. The net difference of astigmatism was -0.27 +/- 3.50. The mean value of vectorial difference for all patients was 4.93 +/- 4.02 D. There was a statistically significant negative correlation between the trephine diameter difference and the vectorial difference (r= -0.582, p<0.01). There was a significant change in vectorial difference values in patients with high pre-suture removal astigmatism. Patients with keratoconus had a positive correlation between the pre-suture removal astigmatism and the vectorial difference (r=0.615, p=0.038).

CONCLUSIONS

After suture removal following PK, unexpected high levels of astigmatic change could be encountered due to donor-recipient trephine diameter difference and underlying primary diagnosis such as keratoconus. In particular, high level astigmatism before suture removal has a greater risk of increased astigmatic change after suture removal.

Late onset Descemet's membrane detachment 20 years after penetrating keratoplasty

This paper reports a case of spontaneous Descemet's Membrane (DM ) detachment 20-years after penetrating keratoplasty (PK). The patient presented with acute onset blurred vision in the right eye associated with mild ocular discomfort. There was no prior history of trauma. The patient had undergone PK in the right eye 20 years back. Detailed ophthalmic examination showed best corrected visual acuity of hand movements close to face in the right eye and 20/80 in the left eye. The right eye showed diffuse graft edema but no congestion, epithelial defect, or loss of continuity of graft-host junction to suggest a traumatic etiology. Anterior segment optical coherence tomography showed DM break with a detachment in the right eye, which was treated with an intracameral C3F8 injection. DM break with detachment post-PK has been very sparsely reported in literature and is an important differential to remember when faced with an edematous graft, in addition to the diagnosis of graft rejection or failure.

Comparison of 12-month anatomic and functional results between Z6 femtosecond laser-assisted and manual trephination in deep anterior lamellar keratoplasty for advanced keratoconus

The management of severe keratoconus requires corneal transplantation, for which the gold standard is deep anterior lamellar keratoplasty (DALK), preserving the healthy Descemet's membrane and endothelium. The safety and reproducibility of corneal cuts have been improved by the evolution of femtosecond lasers in refractive surgery, and femtosecond laser in DALK would seem to provide the same advantages over the manual method. In our retrospective study, we compare functional and anatomical results of femtosecond-assisted DALK versus manual trephination DALK in patients with keratoconus in stage 4 of the Krumeich classification. It is a retrospective study including all patients with stage 4 keratoconus who underwent femtosecond laser-assisted DALK between November 2012 and November 2015 in Nantes university medical center. We compared those patients to a group of patients who underwent manual DALK in the same period, paired by age and maximal keratometry. We assessed visual acuity, pachymetry, endothelial cell density (specular microscopy), and keratometry before surgery and at 4, 8 and 12 months of follow-up. Laser settings and intraoperative complications were recorded. Nineteen patients underwent surgery by femtosecond-assisted DALK, 6 women and 12 men with average age 30.2±10.8 years at transplantation. They were paired with a group of 17 patients who underwent manual DALK in order to compare results. Before surgery, mean visual acuity in the femtosecond group was 0.90 logMAR versus 0.89 logMAR in the manual group, showing no statistically significant difference (P=0.96). Both groups were similar in terms of preoperative age, mean keratometry, pachymetry and endothelial cell density. Average visual acuity post-surgery was 0.27; 0.26; and 0.14 logMAR for femtosecond DALK versus 0.27; 0.17 et 0.25 for manual DALK at 4, 8 and 12 months follow-up respectively, showing no statistically significant difference. After surgery, at 4, 8 and 12 months, mean pachymetry was similar in both groups, and average endothelial cell density was 2390 cells/mm² for femto DALK versus 2531 cells/mm² for manual DALK at 12 months of follow-up, showing no statistically significant difference (P=0.5726). The rate of Descemet's membrane microperforations during the procedure was low and similar for both groups. Our study allows for a 12-month follow-up, with assessment of visual recovery, anatomic result and endothelial safety in a series of 19 femtosecond laser-assisted DALK with no statistical significant difference versus the manual trephination group. Femtosecond laser allows for increased reproducibility of the DALK procedure without reducing adverse effects during surgery. Femtosecond laser seems to improve the technique of the DALK procedure, and future developments could improve the reproducibility of DALK even further. A medical economics study would be necessary to determine the cost-effectiveness of femtosecond laser-assisted DALK.

Microbial Keratitis After Penetrating Keratoplasty

PURPOSE

To report the incidence, microbiological profile, graft survival, and determining factors of microbial keratitis after penetrating keratoplasty (PK).

DESIGN

Observational case series.

METHODS

The study involved 51 patients (52 eyes) who were treated at a single tertiary referral center during a 10-year period. Retrospective chart review included medical records of all patients diagnosed with microbial keratitis after penetrating keratoplasty at the National Taiwan University Hospital between January 2000 and December 2009. The main outcome measures were incidence of graft infection, microbial profile, and graft survival status.

RESULTS

There were 871 PKs performed and 67 episodes in 52 eyes of culture-positive microbial keratitis during the study period. There were 32 infectious episodes (47.8%) in the first year post-PK and 35 episodes (52.2%) after the first year post-PK. Forty-four gram-positive bacterial isolates (57.9%), 17 gram-negative bacterial isolates (22.4%), and 15 fungal isolates (19.7%) were found. Twenty-three (34.3%) grafts remained clear after the infection episode with a mean follow-up of 1127 days (range, 25-3962 days). There was no difference in graft survival rate regarding the original indication of PK or offending pathogen. Suture-related infection was associated with decreased risk of graft failure (P = .02), while the factor associated with increased risk of graft failure was usage of antiglaucoma agents (P = .01).

CONCLUSION

Infectious keratitis after penetrating keratoplasty leads to a high graft failure rate. Such complications can occur before or after the first year post-PK.

Incidence and risk factors for post-penetrating keratoplasty glaucoma: A systematic review and meta-analysis

Objectives

To establish the incidence and risk factors for post penetrating keratoplasty glaucoma (PKKG).

Methods

Studies published between 1947 and 2016 regarding penetrating keratoplasty (PK) were identified using an electronic search and reviewed. For search purpose, PKKG was defined as ocular hypertension (> 21mmHg) after PK. The incidence and risk factors of PKKG were extracted for all studies. Pooled incidence, odd ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

Thirty studies reporting on 27146 patients were included in the analysis of the incidence and risk factors for PKKG. Exact PKKG definitions used in the literature could be classified in to three subgroups: I, ocular hypertension (> 21mmHg) after PK; II, I plus > 4 weeks medical treatment required; III, II plus treatment escalation among patients with preexisting glaucoma. Overall (Definition I) pooled incidence in all studies was 21.5% (95% CI 17.8%, 25.7%). The incidence varied according to different definitions. The highest incidence value was found when only studies using Goldmann tonometer were included (22.5%), while the lowest incidence was found when a strict definition was used and steroid-induced PPKG was excluded (12.1%). The incidence was higher in patients with preexisting glaucoma, bullous keratopathy (BK), aphakia, pseudophakia, failed graft, and surgical indication of trauma. A triple procedure (combined PK with extra capsular cataract extraction and intraocular lens implantation) was not identified as being associated with the increased risk for PKKG.

Conclusions

The overall pooled incidence of PKKG was 21.5%, but it varied according to the criteria used to define the presence of PPKG. Strong risk factors for PKKG included preexisting glaucoma and aphakia, while modest predictors included pseudophakia, regrafting, and preoperative diagnosis like BK and trauma. There may not be sufficient evidence to identify a significant association between a triple procedure and PKKG.