Microsporidial Stromal Keratitis in Post-Keratoplasty Eyes

PURPOSE

The purpose of this paper is to report the clinical manifestations, diagnostic evaluation, management and outcomes of microsporidial keratitis in post-keratoplasty eyes.

METHODS

This is a retrospective review of three patients diagnosed with microsporidial stromal keratitis in post-keratoplasty eyes between January 2012 and December 2021 at a tertiary referral center (Ospedali Privati Forlì "Villa Igea", Forlì, Italy).

RESULTS

All patients presented with fine multifocal granular infiltrates following keratoplasty for a presumed herpetic keratitis. No microorganisms were isolated from the corneal scrapings and no clinical response was observed with broad-spectrum antimicrobial therapy. In all cases, confocal microscopy demonstrated spore-like structures. The histopathologic examination of the excised corneal buttons confirmed the diagnosis of microsporidial stromal keratitis. Following therapeutic keratoplasty and treatment with an initial high dose and extended taper of topical fumagillin, clinical resolution was achieved in all eyes. The Snellen visual acuities at the final follow-up were 20/50, 20/63 and 20/32.

CONCLUSIONS

Prior to definitive surgery, confocal microscopy can be employed for the in vivo detection of pathogenic microorganisms such as Microsporidium. In post-keratoplasty eyes, therapeutic keratoplasty and an initial high dose of topical fumagillin with extended taper can allow the resolution of microsporidial stromal keratitis with a satisfactory visual prognosis.

Case report: A case of acute postoperative endophthalmitis following penetrating keratoplasty due to carbapenem-resistant Klebsiella Pneumoniae and literature review

A 22-year-old lady underwent penetrating keratoplasty for serious keratoconus. The following day, it was complicated by the development of infectious endophthalmitis. The source of infection was identified as carbapenem-resistant Klebsiella pneumoniae. The donor corneal button might be playing a role in infection transmission due to carbapenem-resistant Klebsiella pneumoniae in a sputum culture when the donor was still alive. Nosocomial infections were typically severe, rapidly progressive, and difficult to treat. Finally, the patient underwent therapeutic penetrating keratoplasty again with complete resolution of the infection.

Managing Post-Keratoplasty Astigmatism: High-Tech vs. Low-Tech Imaging Techniques for Guiding Suture Manipulation

Astigmatism is a visually significant condition that can develop after keratoplasty. The management of post-keratoplasty astigmatism can be performed both when transplant sutures are in place and when they have been removed. Fundamental for astigmatism management is its identification and characterization in terms of type, amount, and direction. Commonly, post-keratoplasty astigmatism is evaluated through corneal tomography or topo-aberrometry; however, many other techniques can be used in case these instruments are not readily available. Here, we describe several low-tech and high-tech techniques used for post-keratoplasty astigmatism detection in order to quickly understand if it contributes to low vision quality and to determine its characteristics. The management of post-keratoplasty astigmatism through suture manipulation is also described.

Epstein-Barr Virus Keratouveitis-Induced Malignant Glaucoma After Penetrating Keratoplasty: A Case Report and Literature Review

PURPOSE

To report a case of Epstein-Barr virus (EBV) keratouveitis-induced malignant glaucoma after repeat penetrating keratoplasty (PK).

METHODS

Retrospective review of the patient's medical records and review of literature on EBV corneal endotheliitis and/or anterior uveitis.

RESULTS

A 78-year-old Thai female patient presented with a markedly edematous corneal graft, dense pigmented keratic precipitates, fibrinous anterior chamber reaction, uniformly flat anterior chamber, and ocular hypertension of 55 mmHg in the left eye on the first day after the third PK. An aqueous tap for polymerase chain reaction analysis was positive for EBV DNA but negative for other herpesviruses. The patient was diagnosed with EBV endotheliitis and anterior uveitis-induced malignant glaucoma; and successfully treated with oral valacyclovir and topical 2% ganciclovir eye drops.

CONCLUSIONS

EBV endotheliitis and anterior uveitis can induce malignant glaucoma following PK. A high index of suspicion is required when a patient has a history of unexplained multiple graft rejections.

Histopathology of the Host Cornea Following Penetrating Keratoplasty

INTRODUCTION

To study the ultra-structural changes in the diseased corneal cells by histopathology, electron microscopy, and immunohistochemistry using conventional antisera and monoclonal antibodies with the ultimate goal of justifying pre-treatment and post-treatment advice and, if necessary, modifying the post-operative treatment for improved graft survival.

METHODS

Thirty cases registered for penetrating keratoplasty were worked up for routine systemic and ophthalmic criteria. A full-thickness diseased cornea was subjected to histopathology after suitable staining and fixation, including electron microscopic and immunohistochemical studies where possible.

RESULTS

The ages ranged from four to 60 years. The majority (26%) were in the age group of 31-40 years. The most frequent causes of corneal pathology that underwent keratoplasty include post-traumatic corneal scarring (40%), followed by pseudophakic bullous keratopathy (16.7%). In almost all cases, the histopathology confirmed the existing clinical diagnosis. Histopathology helped to confirm one doubtful case of Fuchs' dystrophy and to contradict one clinical diagnosis of pseudophakic bullous keratopathy, which turned out to be epithelization of the anterior chamber.

CONCLUSION

The results underline the significance of the histopathological study of these corneal conditions to increase the post-surgical survival of the corneal graft.

Incidence, Pathophysiology, Complications, and Management of Positive Vitreous Pressure During Penetrating Keratoplasty: A Literature Review

Positive vitreous pressure (PVP) is common during open anterior segment surgery and penetrating keratoplasty (PKP) has a reported incidence rate of 40-50%. Despite adequate perioperative preventive precautions, positive pressure occurs during surgery and optimum management of PVP is required to avoid serious complications. Many pharmacological and mechanical approaches can be employed either preoperatively or intraoperatively to decrease vitreous pressure. Surgical techniques such as graft-over-host technique, the modified graft-over-host technique, techniques employed mattress sutures and needle, or Vitreous aspiration or vitrectomy can be effectively used to manage intraoperative PVP during PPK. This article reviews the incidence, risk factors, prevention, and different approaches to the management of positive vitreous pressure during PKP to analyze the available evidence in order to improve the safety profile of PKP and prevent sight-threatening complications.

An Overview of Corneal Transplantation in the Past Decade

The cornea is a transparent avascular structure located in the front of the eye that refracts light entering the eyes and also serves as a barrier between the outside world and the internal contents of the eye. Like every other body part, the cornea may suffer insult from trauma, infection, and inflammation. In the case of trauma, a prior infection that left a scar, or conditions such as keratoconus that warrant the removal of all or part of the cornea (keratoplasty), it is important to use healthy donor corneal tissues and cells that can replace the damaged cornea. The types of cornea transplant techniques employed currently include: penetrating keratoplasty, endothelial keratoplasty (EK), and artificial cornea transplant. Postoperative failure acutely or after years can result after a cornea transplant and may require a repeat transplant. This minireview briefly examines the various types of corneal transplant methodologies, indications, contraindications, presurgical protocols, sources of cornea transplant material, wound healing after surgery complications, co-morbidities, and the effect of COVID-19 in corneal transplant surgery.

Impact of pandemic COVID-19 lockdown on penetrating keratoplasty patients

Purpose

To study the impact of the COVID-19 lockdown on the regular follow-up of keratoplasty patients.

Methods

This retrospective interventional case series included 30 patients who had immunological corneal endothelial rejection out of 190 patients who came for post-PKP follow-up between September 15, 2019, and September 30, 2020. The demographics, primary diagnosis, surgical technique, time of presentation, recovery of graft, associated ocular problems, and visual acuity at 1 month were analyzed. Forward stepwise (likelihood ratio) binary logistic regression was used to find significant variables.

Results

The study population had 19 males (63.33%) and 11 females (36.67%). The mean age of the study group was 42.83 ± 18.89 (8-80) years. Of 30 patients, 19 (63.3%) presented before and 11 (36.7%) after the COVID-19 lockdown. Overall, 23 (77%) showed a reversal of graft rejection. Logistic regression showed that preoperative indications, large-sized grafts, and deep corneal vascularization were significant risk factors for non-resolution of graft rejection. It was noted that patients who presented to the hospital late had poor recovery (P = 0.002). The delay in the presentation was a significant risk factor for non-resolution of graft rejection (P < 0.01). Z-test for proportions revealed that the difference in the non-resolution of rejection on immediate or delayed treatment in patients presenting during lockdown (P = 0.002) was significant.

Conclusion

This article is to highlight the impact of the COVID-19 lockdown on graft rejection recovery of PKP patients due to delays in follow-up. Early treatment helps in the recovery of graft transparency and the reversal of immunological graft rejection. Also, primary diagnosis, deep vascularization, and large-sized grafts were significant risk factors for non-resolution of graft rejection.

Evaluating Keratoplasty for Fuchs' Endothelial Corneal Dystrophy: A Literature Review

Fuchs' endothelial corneal dystrophy (FECD) is progressive corneal endothelium dysfunction, characterised by corneal oedema, and potential blindness if left untreated. Keratoplasty is the only definitive treatment to restore vision in FECD, with different surgical techniques being described. The corneal transplant has been described as the most commonly performed and most successful allogenic transplant globally; therefore, it is crucial to dissect it further since a large proportion of the population worldwide is likely to be impacted. We feel that an updated literature review is both very relevant and necessary at present and aim to amalgamate more recent data on the topic (including meta-analyses, systematic reviews, and randomised control trials (RCTs), among others). We acknowledge that the paucity of reliable data limits progress for FECD and that there are existing ethical complexities in performing prospective trials on patients.  Traditionally, the surgery for FECD was limited to penetrating keratoplasty (PK), yet recent developments have introduced more advanced procedures and adapted the existing ones, to provide treatment specific to the disease-affected corneal layers. The questions we will address encompass: how does the severity of FECD govern the treatment options available, what are the differences between PK and types of endothelial keratoplasty (EK), what are the expected clinical outcomes of each of these operations, what are the potential concerns with the idealistic descemetorhexis surgery, and what do we envisage for times to come? Besides this, novel minimally-invasive pharmacological techniques are now being trialled, such as Rho kinase (ROCK) inhibition and cultured endothelial cells (CECs), which may drastically improve the dependence on corneal donors. We examine and critically appraise the literature to explore the understanding of FECD, and the treatment options that exist: historically, currently, and those anticipated for the future.

[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.

Penetrating Keratoplasty: Indications and Graft Survival by Geographic Region

Corneal transplantation, or penetrating keratoplasty (PK), is the most common form of solid-organ transplantation performed worldwide. Here, we evaluated the indications for PK and rates of transplant survival around the world by geographic region. We conducted a literature search of PubMed, MEDLINE, and Google Scholar databases and identified 155 relevant studies from 41 countries published between 1987 and 2021. The most common indications for PK were keratoconus in Europe, Africa, the Middle East, Australia, New Zealand, and Central and South America, bullous keratopathy in North America, and corneal scarring in Asia. The overall global mean graft survival rates at 1-, 2-, 3-, 5-, and 10-years were 88.6%, 81.2%, 78.9%, 72.8%, and 61.2%, respectively. Through this systematic analysis of PK by region, we hope to bring a new perspective to the corneal transplantation literature and to potentially highlight global differences and unmet needs in patient care.

Pars plana vitrectomy and therapeutic keratoplasty in endophthalmitis and infectious keratitis

PURPOSE

To describe the anatomical and functional outcomes of patients with infectious keratitis (IK) and secondary endophthalmitis who underwent penetrating keratoplasty (PK) after pars plana vitrectomy (PPV) assisted by temporary keratoprosthesis (TKP).

METHODS

An observational retrospective case series was performed. Data were collected from January 2013 to July 2020. Patients over 18 years old with a clinical and microbiological diagnosis of IK, and clinical, ultrasonographic, and or microbiological diagnosis of endophthalmitis were included. Anatomical success was defined as infection resolution with preservation of the ocular globe integrity. No change or improvement of best-corrected visual acuity (VA) at the last follow-up was considered as a functional success.

RESULTS

A total of 32 eyes of 32 patients were analyzed. The anatomic success was obtained in 87.5% eyes in which the infection was eradicated. The 63% patients maintained or improved their best-corrected VA, 37.5% ended up with hand motion VA.

CONCLUSIONS

Our results suggest that PPV assisted by TKP followed by PKP can be a good approach for treating patients with endophthalmitis secondary to IK while allowing further visual improvement after an optical PK. Further prospective studies need to be done to evaluate final visual rehabilitation of these patients.

Prevalence of Herpesvirus DNA in Corneal Transplant Recipients

Purpose: Graft failure after penetrating keratoplasty (PK) is a serious complication, especially in eyes with herpetic keratitis (HK). This study evaluated the prevalence and graft survival of herpes simplex virus type 1 (HSV-1) and varicella zoster virus (VZV) DNA in recipient corneas during PK. Methods: The retrospective study was performed at the Department of Ophthalmology at University Hospital in Mainz, Germany. We analyzed data from every patient who underwent PK between January 2020 and June 2021. According to our clinical routine, we performed HSV-1 and VZV polymerase chain reaction (PCR) on all excised corneal buttons regardless of the primary clinical diagnosis. Results: We included 112 eyes of 112 consecutive patients who underwent PK. At the time of PK, 91 (81.25%) patients had no history of HK and 21 (18.75%) patients did. The recipient corneas of 91 patients without a history of HK tested positive for HSV-1 DNA in 12 (13.2%) eyes, for VZV DNA in 3 (3.3%) eyes, and for HSV-1 and VZV DNA simultaneously in 2 (2.2%) eyes. The recipient corneas of 21 patients with a preoperative history of HK tested positive for HSV-1 DNA in 13 (61.9%) eyes and VZV DNA in 1 (4.8%) eye. All patients with positive herpes DNA and no history of HK prior to PK received antiherpetic treatment and had a 100% graft survival rate after 1 year. Conclusions: We found herpesvirus DNA in 18.7% of recipient corneas without clinical suspicion or history of herpes keratitis. This suggests the need of routine HSV-1 and VZV PCR testing in all explanted corneas regardless of clinical suspicion, to detect, treat and prevent possible recurrence of herpes infection in corneal grafts and support graft survival.

Incidence of Complications Related to Corneal Graft in a Group of 758 Patients

Purpose: this study aimed to assess the frequency of complications related to corneal grafts, including epithelialization disorders, wound dehiscence, infectious keratitis, recurrence of herpetic keratitis, graft rejection, late graft failure, and infectious and noninfectious corneal melting, while also considering risk factors, particularly indications. Methods: this retrospective analysis of corneal graft failure included a chart review of the hospital records of patients who underwent penetrating keratoplasty (PK) between January 2016 and December 2020 at the Department of Ophthalmology of the District Railway Hospital, Katowice, Poland. Results: Between 2016 and 2020, a total of 758 PK procedures were carried out at the ophthalmology department. Bullous keratopathy (20.58%), keratoconus (18.07%), and corneal perforation (13.32%) were the primary indications for keratoplasty. Secondary glaucoma was diagnosed in 99 patients (13.06%). The success rate of PK was 72.43% (494). The most frequent treatment complication was secondary glaucoma (13.06%), followed by late endothelial failure, perforation (4.1%), and bacterial keratitis (3.23%). Patients in the high-risk group were 4.65 times more likely to develop complications than those in the low-risk group. Multivariate regression analysis showed that concomitant ophthalmic diseases (odds ratio (OR): 3.12, confidence interval (CI): 1.60−6.08, p = 0.00) and connective tissue diseases (OR: 7.76, CI: 2.40−25.05, p = 0.00) were significant factors associated with the occurrence of complications. Diabetes, dermatological diseases, primary glaucoma, and sex were not associated with corneal graft failure (p > 0.05). Conclusion: Chronic loss of the endothelium was the primary cause of graft failure in individuals who underwent PK. The high-risk transplant has up to 4.65 times higher risk of complications compared to the indications with a good prognosis.

Outcomes of Pythium keratitis: a meta-analysis of individual patient data

Background

Pythium keratitis is a difficult-to-treat corneal infection.

Methods

A meta-analysis of individual patient data from observational studies of Pythium keratitis was performed. The outcomes of interest were therapeutic penetrating keratoplasty (TPK) and globe removal (evisceration, enucleation, or exenteration); the main exposures were linezolid and azithromycin use.

Findings

Of 46 eligible articles, individual patient data were available for 306 eyes (34 studies). Pythium keratitis was associated with high rates of TPK (80%, 95%CI 70-87%) and globe removal (25%, 95%CI 13-43). In multivariable models adjusting for age and country, fewer TPKs were performed in patients treated with azithromycin (RR=0.80, 95%CI 0.67-0.96; P=0.04) and linezolid (RR=0.82, 95%CI 0.67-0.99; P=0.02).

Conclusions

Studies of Pythium keratitis reported high rates of TPK and globe removal. Use of azithromycin and linezolid was associated with a lower rate of TPK. While promising, these results should be interpreted with caution given the biases inherent to observational studies.

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.

Current approaches in the management of patients with keratoconus

Keratoconus is a relatively frequent eye disease, especially in young patients, in which the cornea gradually thins and deforms in a cone shape. In the past, it could be treated only with glasses, rigid contact lenses or, for advanced cases, penetrating corneal transplant. Nowadays, corneal cross-linking, intracorneal ring segments implantation or deep anterior lamellar keratoplasty are available options of treatment, along with the above mentioned ones. Several studies focused on this disease and its management attempted to establish the applicability of these treatment methods in current practice. In the early stages, glasses or soft toric contact lenses are able to correct the astigmatism, but, as the disease progresses, rigid contact lenses are indicated. Corneal cross-linking is done in order to slow down or even stop the progression of the disease. Implanting intracorneal ring segments helps improve visual acuity in patients with low vision that cannot be corrected otherwise. Advanced stages need corneal transplant, either penetrating or anterior lamellar, depending on each patient's ocular characteristics. Thus, keratoconus treatment is individualized for every patient, according to the stage of the disease. Moreover, because of the new developed technology, keratoconus patients can benefit from efficient treatment, in much safer conditions.

Acute Rejection Following COVID-19 Vaccination in Penetrating Keratoplasty in a Young Male - A Case Report and Review of Literature

PURPOSE

To report a case of a boy with acute keratoplasty rejection manifesting 12 days after receiving BNT162b2 messenger RNA (mRNA) vaccine for COVID-19.

STUDY DESIGN

A case report.

RESULTS

A 15-year-old boy with a history of penetrating keratoplasty due to acanthamoeba keratitis developed corneal decompensation 12 days after BNT162b2 messenger RNA vaccine for COVID-19 disease. One-week treatment with topical Dexamethasone 2% eye drops resulted in a complete resolution of corneal edema.

CONCLUSIONS

This case suggests that BNT162b2 messenger RNA (mRNA) vaccine can be associated with acute keratoplasty rejection in children, which responds completely to topical steroids. Ophthalmologists should be aware of this risk of cornea decompensation after COVID-19 vaccine in children who received a cornea transplant.

Outcomes of Severe Fungal Keratitis Using in vivo Confocal Microscopy and Early Therapeutic Penetrating Keratoplasty

Purpose

The purpose of this study was to assess the impact of early diagnosis using in vivo confocal microscopy and early therapeutic penetrating keratoplasty (TPK) on the outcomes of severe cases of fungal keratitis.

Methods

This retrospective single-center study included 38 patients (40 eyes) with fungal keratitis who presented between December 2013 and February 2020. Preoperative, intraoperative, and postoperative parameters were recorded to assess the role of early correct diagnosis and early surgical therapy on visual acuity outcome and enucleation rate during follow-up.

Results

The mean patient age was 51 years (71% females). The initial external diagnosis was correct in 20 cases (50%). The mean time from symptom onset until admission to our department was 46.8 ± 68.0 (median 28.5) days. The mean time to correct diagnosis after admission to our department was 1 day with in vivo confocal microscopy (IVCM). IVCM was performed in 38 cases, of which 36 (sensitivity: 94.7%) were positive for fungal infection. Twenty-seven out of 40 (67.5%) eyes received a TPK 4.2 ± 3.9 days after admission, with a mean graft size of 8.9 ± 1.9 mm. Three eyes (7.5%) were enucleated. The corrected distance visual acuity of the entire study population increased from 2.0 ± 1.2 LogMAR to 0.96 ± 1.17 LogMAR.

Conclusion

In vivo confocal microscopy is a powerful tool for the early detection of fungal organisms in infectious keratitis. An early TPK with a large graft helps to eradicate the infection timely and results in a favorable visual acuity outcome and lower enucleation rate, especially when treating filamentous fungi.

Eight-years Egyptian experience of Boston type I keratoprosthesis following failed penetrating keratoplasty or ocular surface disease

PURPOSE

To evaluate the outcome and complications after implantation of the Boston type I keratoprosthesis (Kpro) in two groups of eyes.

METHODS

We retrospectively reviewed records of 28 eyes with failed Penetrating keratoplasty (PKP) (Group A) and 31 eyes with severe ocular surface diseases who implanted Kpro. Follow-up was performed for a mean 37 months. Primary outcomes were Kpro retention and visual improvement, secondary outcomes included the occurrence of complications as endophthalmitis, retro-prosthesis membrane (RPM), intraocular pressure (IOP) abnormalities, posterior capsule opacification (PCO), graft thinning and extrusion.

RESULTS

Visual improvement was achieved in 20 eyes in Group A, and in 19 eyes in Group B. In group A, the prosthesis was retained in 25 eyes, while prosthesis retention in Group B was in 26 eyes. Group A had higher rates of PCO, high IOP, soft IOP, and graft thinning. Group B had higher risk of RPM, and endophthalmitis. Two eyes in Group A, and Five eyes in Group B required redo procedure.

CONCLUSION

The Boston Kpro type I is an effective procedure in eyes with high risk of keratoplasty failure and in severe ocular surface diseases, it has a high retention rate, higher in cases following failed PKP.

Machine Learning to Analyze Factors Associated With Ten-Year Graft Survival of Keratoplasty for Cornea Endothelial Disease

Purpose

Machine learning analysis of factors associated with 10-year graft survival of Descemet stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PK) in Asian eyes.

Methods

Prospective study of donor characteristics, clinical outcomes and complications from consecutive patients (n = 1,335) who underwent DSAEK (946 eyes) or PK (389 eyes) for Fuchs’ endothelial dystrophy (FED) or bullous keratopathy (BK) were analyzed. Random survival forests (RSF) analysis using the highest variable importance (VIMP) factors were determined to develop the optimal Cox proportional hazards regression model. Main outcome measure was 10-year graft survival with RSF analysis of factors associated with graft failure.

Results

Mean age was 68 ± 11 years, 47.6% male, in our predominantly Chinese (76.6%) Asian cohort, with more BK compared to FED (62.2 vs. 37.8%, P < 0.001). Overall 10-year survival for DSAEK was superior to PK (73.6 vs. 50.9%, log-rank P < 0.001). RSF based on VIMP (best Harrell C statistic: 0.701) with multivariable modeling revealed that BK (HR:2.84, 95%CI:1.89–4.26; P < 0.001), PK (HR: 1.64, 95%CI:1.19–2.27; P = 0.002), male recipients (HR:1.75, 95%CI:1.31–2.34; P < 0.001) and poor pre-operative visual acuity (HR: 1.60, 95%CI:1.15–2.22, P = 0.005) were associated with graft failure. Ten-year cumulative incidence of complications such as immune-mediated graft rejection (P < 0.001), epitheliopathy (P < 0.001), and wound dehiscence (P = 0.002) were greater in the PK compared to the DSAEK group.

Conclusion

In our study, RSF combined with Cox regression was superior to traditional regression techniques alone in analyzing a large number of high-dimensional factors associated with 10-year corneal graft survival in Asian eyes with cornea endothelial disease.

Endoilluminator-aided cataract surgery in eyes with corneal opacity - A modified surgical approach

Background

Cataract and corneal blindness continue to be leading causes of reversible blindness in India. These can co-exist in a multitude of pathologies such as trauma, healed keratitis (old herpetic scar), chronic degenerative changes such as labrador keratopathy, bullous keratopathy, corneal dystrophies etc. Phacoemulsification in such eyes is rewarding to the patient in terms of minimal intervention, less risk of complications owing to reduced open sky time (as in case of combined keratoplasty), and better predictable visual outcomes. Approach to such eyes with poor visualisation is highly challenging.

Purpose

We illustrate a modified surgical technique of chandelier illumination through pars plana for cataract surgery in eyes with corneal opacity of varying grades.

Synopsis

Five patients with dense cataract and small pupils, associated with corneal opacity (leucomatous and macular grade) are described. Closed chamber phacoemulsification with intraocular lens with or without pupil expanders was performed assisted by 23 or 25 gauge pars plana chandelier illumination introduced in the vitreous cavity through a sclerotomy wound made prior to phacoemulsification in the inferotemporal quadrant.

Highlights

Chandelier illumination aids in reducing the light scatter that occurs due to corneal opacity. Ease of visualisation of lens structures and of performing cataract surgery was noticed. One case was combined with penetrating keratoplasty with reduced open sky time. This assisted technique has advantages such as enhancing visualisation intraoperatively and allowing working in closed chamber. Its self-retaining nature aids bimanual manipulation. No complications were encountered. The video highlights the utility, advantages and practicality of chandelier retroillumination in patients with corneal opacities of varying degree undergoing phacoemulsification.

Video Link

https://youtu.be/I3z6QG-_wD8.

Evaluation of the Clinical Findings of Patients with Penetrating Keratoplasty Followed by Telephone Due to the COVID-19 Pandemic

Objectives:

To evaluate changes in the clinical findings of keratoplasty patients who could not be examined face-to-face and were followed up by telephone during the coronavirus disease 2019 (COVID-19) pandemic.

Materials and Methods:

Patients with penetrating keratoplasty who presented to the cornea department between March 2020 and February 2021 were grouped according to whether they showed clinical deterioration (Group 1: no deterioration, Group 2: deterioration). The patients’ last visit prior to the COVID-19 pandemic and their first visit after the pandemic-related lockdown ended were evaluated. The demographic data, follow-up period, and ophthalmological examination findings of all patients were recorded and the data were compared between the groups.

Results:

Thirty-five eyes of 35 patients were included in the study. Signs of deterioration were detected in 8 (22.8%) of the patients (Group 1), while no deterioration was detected in 27 (77.2%) of the patients (Group 2). In the last follow-up visit prior to the COVID-19 pandemic, mean best corrected visual acuity (BCVA) was 1.26±0.43 LogMAR (range: 0.52-1.80) in Group 1 and 1.41±1.02 LogMAR (range: 0-3.1) in Group 2 (p=0.692). Mean BCVA in the first control during the pandemic was 2.07±0.86 LogMAR (range: 1.3-3.1) in Group 1 and 1.49±1.08 LogMAR (range: 0-3.1) in Group 2 (p=0.08). At the first visit during the COVID-19 pandemic, the mean intraocular pressure of Group 1 was 16.38±8.58 mmHg (range: 0-31), and Group 2 was 17.11±3.7 mmHg (range: 11-26) (p=0.984).

Conclusion:

The continuation of treatment initiated prior to the pandemic was probably the most important reason why deterioration was not observed in keratoplasty patients. In situations such as pandemics where face-to-face visits with patients may be disrupted, it may be possible to follow the patients safely with telemedicine visits until the difficult circumstances resolve.

Indications and outcomes of pediatric penetrating keratoplasty: A retrospective observational study

Background

Pediatric corneal transplantation can be indicated in congenital and acquired conditions. Challenges include preoperative evaluation, multiple intraoperative obstacles, and postoperative problems in follow-up and management. This study was aimed at identifying the indications and clinical outcomes of pediatric penetrating keratoplasty (PKP) in Jordan.

Methods

This retrospective cohort study was conducted in Amman, Jordan. Using the hospital's electronic database, all medical records of patients aged < 18 years who underwent PKP between January 2004 and October 2019 were reviewed. Preoperative evaluations included best-corrected distance visual acuity (BCDVA) and anterior and posterior segment examinations. Postoperative complications, BCDVA, and graft survival were examined 1 year postoperatively.

Results

A total of 149 cases of pediatric PKP were performed on 141 eyes of 118 patients with an age mean ± standard deviation (SD) of 11.44 ± 4.97 years at the time of surgery. Acquired non-traumatic corneal pathologies accounted for 65.8% of indications for PKP. The most frequent indication was advanced keratoconus (55.7%). Preoperative and 1-year postoperative BCDVAs significantly differed (P < 0.001), with 111 (74.5%) patients showing improved BCDVA, 12 (8.05%) patients showing worsened BCDVA, and 26 (17.45%) patients showing no change in BCDVA. The overall 1-year graft survival rate was 80.54%.

Conclusions

This was the largest study in Jordan involving pediatric patients who underwent PKP for various indications, showing a significant improvement in BCDVA, with a high survival rate at 1 year. Future studies with longer follow-up periods could provide stronger evidence for surgical outcomes and graft survival. Further, the option of lamellar keratoplasty in the pediatric age group should be assessed.

Comparison of Glaucoma Therapy Escalation After Penetrating Keratoplasty to Descemet Stripping Automated Endothelial Keratoplasty for the Treatment of Pseudophakic Bullous Keratopathy: A Cohort Study

PURPOSE

The purpose of this study was to compare glaucoma therapy escalation (GTE), graft survival, vision, and glaucoma following penetrating keratoplasty (PK group) and Descemet stripping automated endothelial keratoplasty (DSAEK group) to treat pseudophakic bullous keratopathy (PBK).

METHODS

This cohort included cases of PBK managed with PK from 2009 to 2014. We compared the incidences and determinants of GTE, graft survival, and visual disability. P < 0.05 was statistically significant.

RESULTS

There were 58 eyes in the PK group and 117 eyes in the DSAEK group. The incidence of GTE in the PK and DSAEK groups at the last follow-up was 34.2% (95% confidence interval [CI]: 19.5-48.9) and 46.6% (95% CI: 27.7-65.4), respectively. The risk of GTE was similar between the groups (relative risk [RR] = 1.36 [95% CI: 0.94-1.98], P = 0.12). GTE was significantly associated with graft survival in the PK group (RR = 3.25 [95% CI: 1.5-7.0], P < 0.001) and the DSAEK group (RR = 3.77 [95% CI: 2.6-5.6], P < 0.001). Glaucoma (P = 0.001) and previous keratoplasty (P < 0.001) were significant predictors for GTE. At the final follow-up visit, severe visual disability was not significantly different between the groups (RR = 0.9 [95% CI: 0.3-2.9], P = 0.88). There was a statistically significant improvement in vision after DSAEK (P < 0.001) but not after PK (P = 0.67).

CONCLUSION

GTE was similar in eyes with PBK managed by PK or DSAEK. Glaucoma and previous keratoplasty were predictors of GTE post-keratoplasty. DSAEK gave better visual outcomes than PK for managing PBK.