Management of Corneal Clouding in Patients with Mucopolysaccharidosis

Mucopolysaccharidoses (MPS) are a rare group of lysosomal storage disorders characterized by the accumulation of incompletely degraded glycosaminoglycans (GAGs) in multiple organ systems including the eye. Visual loss occurs in MPS predominantly due to corneal clouding and retinopathy, but the sclera, trabecular meshwork and optic nerve may all be affected. Despite the success of therapies such as enzyme replacement therapy (ERT) and hematopoietic stem-cell transplantation (HSCT) in improving many of the systemic manifestations of MPS, their effect on corneal clouding is minimal. The only current definitive treatment for corneal clouding is corneal transplantation, usually in the form of a penetrating keratoplasty or a deep anterior lamellar keratoplasty. This article aims to provide an overview of corneal clouding, its current clinical and surgical management, and significant research progress.

A Corneal Perforation Related to Beauveria Bassiana and Post-Penetrating Keratoplasty Management Discussion

Fungal keratitis is an infection that is insidious and frequently misdiagnosed. Those with chronic eye surface conditions, contact lenses, systemic immunosuppression, and diabetes have been the most frequently affected with fungal keratitis. An 84-year-old male patient with a history of bilateral penetrating keratoplasty (PK) for keratoconus presented with pain and decreased visual acuity on his left eye. A corneal perforation was found, which was treated immediately with a full-thickness corneal transplant. The specimen was sent for bacterial and fungal cultures. Topical corticosteroids were prescribed postoperatively. Beauveria bassiana was isolated from the corneal scrapings. The postoperative treatment was modified by reducing the dose of corticosteroid and adding topical natamycin together with systemic posaconazole. No recurrence occurred in the transplant four months postoperatively under topical dexamethasone 0.1% b.i.d. 

This is the first case of keratitis and perforation in a previously transplanted cornea. Due to the rarity of the infection, there are no clear guidelines for postoperative prophylaxis in B. bassiana infection. Either the continuation of corticosteroids or the switch to another immunosuppressive therapy and selecting the appropriate antifungal regimen posed a significant therapeutic dilemma.

Medium-Term Clinical Outcomes of Deep Anterior Lamellar Keratoplasty versus Penetrating Keratoplasty for Macular Corneal Dystrophy

Purpose

To compare the postoperative outcomes of deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PKP) for macular corneal dystrophy (MCD).

Design

Single-center, retrospective, interventional case series.

Methods

A chart review was performed of 100 patients (157 eyes) who underwent primary DALK (DALK group) and PKP (PKP group) for histopathologically confirmed MCD for whom at least 12 months of follow-up were available. Between-group comparisons were performed of visual acuity (VA), graft survival, and postoperative complications.

Results

There were 22 eyes in the DALK group and 135 in the PKP group. Postoperative best-corrected visual acuity (BCVA) of 20/40 or better was achieved in 90.9% of the DALK group and 76.3% of the PKP group (P=0.12). At last visit, graft survival was 95.5% (21 eyes) and 91.1% (123 eyes) in DALK and PKP groups, respectively (P=0.69, Log rank test). Corneal graft rejection episodes occurred in 1 (4.5%) DALK graft and 19 (14.1%) PKP grafts. Five of the 19 graft rejections in the PKP group were irreversible. Microbial keratitis and cataract occurred in 6 (4.5%) and 15 (11.1%) PKP eyes. One (4.5%) eye in the DALK group had cataract and none of the DALK cases developed microbial keratitis. Clinically significant recurrence was observed in 4 (2.9%) PKP eyes and 1 (4.5%) DALK eye (P=0.69), respectively.

Conclusion

DALK is a viable option for MCD without Descemet membrane involvement. DALK had comparable medium-term visual and survival outcomes to PKP. DALK has the advantage of lower open sky intraoperative complications and lower graft rejection episodes.

Descemet membrane suturing to manage recurrent graft detachment in a patient with Descemet membrane endothelial keratoplasty on failed penetrating keratoplasty

A 65-year-old patient with history of keratoconus, mild cataract and penetrating keratoplasty over 30 years ago developed corneal oedema subsequent of graft failure with best corrected visual acuity (BCVA) of counting fingers. He underwent a successful cataract surgery combined with a 7.25 mm Descemet’s Membrane Endothelial Keratoplasty (DMEK) with Sodium Hexafluoride (SF6) gas. His cornea remained oedematous inferiorly at 4 weeks, despite two subsequent re-bubbling due to persistent DMEK detachment inferiorly. This was managed by three radial full thickness 10-0 nylon sutures placed in the inferior cornea along with intracameral injection of air. Following this, his anterior segment ocular coherence tomography (OCT) confirmed complete attachment of the graft, and the sutures were removed 4 weeks later. Unaided visual acuity was 20/63 and BCVA was 20/32 after 8 months. DMEK suturing can be helpful in persistent DMEK detachments, which is refractory to repeated re-bubbling due to uneven posterior surface of previous PK.

Profile of donors and corneal tissue obtained through hospital cornea retrieval programme in a recently established eye bank of a tertiary care teaching hospital of Eastern India

Context:

There is a global need for quality eye banking practices and sensitization of primary care physicians toward corneal donation.

Aims:

To evaluate performance of a recently established eye bank (EB) and quality of corneas obtained, and identify areas of improvement during procurement and utilization of donor corneas.

Settings and Design:

This retrospective observational study is based on records of corneas collected through hospital cornea retrieval programme (HRCP) in the EB of a tertiary care institution during the first 2 years of its establishment.

Methods and Material:

Data on demographic characteristics of donors, death-preservation interval, specular microscopy parameters of corneas, indications for utilization, and reasons for non-utilization of corneas were collected.

Statistical Analysis Used:

Means, standard deviation, range, frequencies, and proportions were analyzed. Spearman's correlation coefficient and Kruskal–Wallis test were applied taking P < 0.05 as significant.

Results:

The EB retrieved 54 corneas from 27 donors with mean age 42.3 ± 24.2 years. All tissues were preserved in Cornisol®. Majority (50%) of transplantable tissues had an endothelial cell density (ECD) between 2,000 and 2,500 cells/mm². ECD decreased significantly with increasing age (Spearman's ρ -0.747, P < 0.001; Kruskal–Wallis P < 0.001). Overall utilization rate of tissues was 87.04% (47/54), and utilizable corneas (50/54, 92.6%) were mainly used for optical purposes (34/50, 68%).

Conclusions:

Successful HCRP of the recently established EB has shown considerable promise in terms of quality and utilisation of corneas. There is need for active involvement of primary care physicians in contributing to increasing voluntary eye donation through awareness, advocacy, and social mobilization.

Advances in corneal graft rejection

PURPOSE OF REVIEW

Immune rejection after corneal transplantation is a major risk for graft failure. We aim to summarize recent advances in the understanding and management of graft rejection.

RECENT FINDINGS

Immune rejection remains the leading cause of graft failure in penetrating keratoplasty (PKP). While ABO blood type and sex match between donor and recipient may reduce rejection, human leucocyte antigens class II matching in a randomized study did not reduce the risk of rejection in high-risk PKP. Compared with PKP, deep anterior lamellar keratoplasty, descemet stripping automated endothelial keratoplasty, and descemet membrane endothelial keratoplasty have lower immune rejection rates of 1.7-13%, 5-11.4%, and 1.7-2.8%, respectively, based on long-term (5 years and more) studies. Whether immune rejection is a major risk factor for graft failure in these lamellar keratoplasties is unclear. While there have not been major advances in the systemic management of graft rejection, topical nonsteroid agents such as tacrolimus and anti-vascular endothelial growth factor have shown promise in high-risk cases.

SUMMARY

Immune rejection remains the leading cause of graft failure in PKP. Lamellar keratoplasties have significantly lower rejection rates compared with PKP. The significance of rejection in the failure of lamellar grafts warrants further investigation.

Why a dedicated section on keratoconus in the European Journal of Ophthalmology?

Keratoconus is emerging as a new subspecialty in ophthalmology. The literature is booming with publications on the topic as we have better understanding of the pathophysiology, treatment and prognosis of the disease over the past two decades. Advances in diagnostic tools as well as genuine increase in prevalence have shifted perspective of the disease from being a rare one. Early diagnosis is of public health interest as early treatment arrests progression. With the view to encourage research, increase awareness and to reflect the evolution of knowledge related to keratoconus, the European Journal of Ophthalmology has dedicate a special section on keratoconus in its journal.

Visual Outcomes in Pediatric Patients with Peters Anomaly

Purpose

This study aimed to evaluate the visual outcomes of pediatric patients diagnosed with Peters anomaly (PA) in a tertiary eye care center.

Methods

This was a retrospective study undertaken at a single academic center. Clinical records of pediatric patients diagnosed with PA from 2000 to 2017 were reviewed. Parameters recorded included visual acuity (VA), intraocular pressure (IOP), presence of glaucoma, and surgical procedures performed. The impact of PA type on final visual acuity levels was analyzed using generalized estimation equation models.

Results

Twenty-one eyes from 11 patients were analyzed. At the final visit, 9 eyes (42.8%) had a VA ≥20/200, while 12 (57%) had <20/200, ranging from 20/250 to no light perception. Of the study cohort, 15 (71.5%) eyes had type I, while six (28.5%) had type II PA. Glaucoma was present in 20 eyes (95%) at the final visit. One eye had dense central leucoma and microphthalmos where IOP could not be measured accurately. Seventeen eyes (81%) underwent at least one intraocular surgery, while the average number of surgeries per eye was 2.9 ± 2.5 (range=0– 9). The type of PA beta(se)=0.53 (0.41), p = 0.20] was not found to be a significant risk factor for worse VA.

Conclusion

Severe visual impairment develops in the majority of patients with PA. The type of anomaly does not appear to be associated with a worse visual function in patients with PA. Glaucoma develops in a high percentage of this patient population, and thus close monitoring of IOP in this patient population is crucial.

Comparison of complications and visual outcomes between big-bubble deep anterior lamellar keratoplasty and penetrating keratoplasty for fungal keratitis

BACKGROUND

To compare the postoperative complications and visual outcomes of big-bubble deep anterior lamellar keratoplasty (BB-DALK) and penetrating keratoplasty (PK) for fungal keratitis (FK).

METHODS

This retrospective study included 94 cases of BB-DALK for FK and 161 cases of PK for FK from a tertiary ophthalmology care centre.

RESULTS

The most common FK pathogens were Fusarium (n = 84, 32.9%) and Aspergillus (n = 67, 26.3%). The recurrence rates after BB-DALK and PK were 3.2 and 5%, respectively (p = 0.723). The follow-up duration was 31.9 ± 15.8 months in the BB-DALK group and 33.9 ± 15.0 months in the PK group. The immune rejection rate was significantly lower in the BB-DALK group than in the PK group (1.1 vs. 18.6%, p < 0.001), as was the incidence of secondary glaucoma (p = 0.018). Endothelial cell density in the BB-DALK group tended to be stable at postoperative month 6, whereas the PK group still attenuated at a hyper-physiological rate. Postoperative best-corrected visual acuity (BCVA) significantly improved in both groups (p < 0.001). No significant difference between-group was observed in BCVA, refractive cylinder, and spherical equivalent postoperatively.

CONCLUSION

Big-bubble DALK is a useful and safe alternative to PK for medically uncontrolled FK.

Late-onset spontaneous Descemet's membrane detachment post penetrating keratoplasty in a patient with congenital glaucoma

A 27-year-old female presented with a sudden decrease of vision in the left eye (OS). Ocular history included advanced congenital glaucoma and previous (15 years) bilateral penetrating keratoplasty and cyclophotocoagulation (9 months) in the left eye. The patient had microcystic corneal edema and Descemet's membrane (DM) detachment; imaging confirmed the detachment with no detectable breaks. DM re-attachment was attempted with an intracameral air bubble tamponade. The edema improved 10 days postoperatively and the graft became clear. Late-onset DM detachment following keratoplasty can occur in patients with congenital glaucoma with no history of recent trauma or eye rubbing. The exact mechanism is unknown, but transscleral cyclophotocoagulation may have a causative role. Timely treatment with air injection results in successful anatomic outcomes.

Outcomes of keratoplasty in a cohort of Indian patients with xeroderma pigmentosum

Purpose:

To evaluate the outcomes of keratoplasty for xeroderma pigmentosum (XP) performed at a tertiary eye care center.

Methods:

A retrospective review of medical records of those patients who were clinically diagnosed to have XP (54 eyes of 36 patients) and underwent keratoplasty; either deep anterior lamellar keratoplasty (DALK, four eyes), endothelial keratoplasty (EK, eight eyes), or penetrating keratoplasty (PK, 42 eyes) from 1994 to 2018.

Results:

The median age at surgery was 20.6 years (interquartile range [IQR], 14.6–27.6 years) and 20 (55.6%) were males. Graft failure occurred in 15 eyes (35.7%) in the PK group and two eyes (50%) in the DALK group; none failed in the EK group. The probability of graft survival in the PK group was 97.2% ± 2.7% at 1 year, 74.0% ± 8.0% at 2 years, and 54.8% ± 11.7% at 5 years. In the PK group, 13 eyes needed antiglaucoma medications, 11 eyes developed graft infiltrate, and 13 eyes needed secondary interventions (cataract surgery, excision biopsy, and tarsorrhaphy). In the EK group, three eyes needed secondary interventions (excision biopsy). Median postoperative endothelial cell density at the last follow-up in the PK group was 1214 cells/mm² (IQR, 623–2277 cells/mm²).

Conclusion:

Despite the complexities of the ocular surface and adnexal issues in XP, keratoplasty had reasonably good outcomes. More than half of the PK grafts survived 5 years with no failures in the EK group. Regular follow-up and timely management of suture-related infections raised intraocular pressure, and suspicious ocular surface lesions, in addition to solar protection, are important for the success of keratoplasty in these eyes.

Specular microscopy in clinical practice

Specular microscopy is a noninvasive diagnostic tool that allows for in vivo evaluation of corneal endothelium in health and various diseased states. Endothelial imaging helps in the diagnosis and management of several endothelial disorders. The review focuses on the principles of specular microscopy, limitations of endothelial imaging, and its interpretation in common conditions seen in the clinical practice. A thorough PubMed search was done using the keywords specular microscopy, corneal endothelium, and endothelial imaging.

Acute onset of deep calcareous degeneration treated with keratoplasty procedures: Two cases report

There are two types of corneal calcium deposition, one is calcific band keratopathy and another is calcareous degeneration. We report two cases of acute onset of calcareous degeneration after using topical eye drops for their corneal wounds. The calcification in both the cases developed within 1 month. Due to the deeper stromal opacity, calcareous degeneration was impressed. In our cases, the deposits were too deep that they required keratoplasty procedures as better treatment options. One of the cases was treated with penetrating keratoplasty and another case was treated with deep anterior lamellar keratoplasty. Both of our cases had stable corneal grafts, and there were no ocular inflammation and no recurrence of calcification at least for 6 months.

Mini-Scleral Contact Lens for Asian Eyes Post-Penetrating Keratoplasty with Smaller Palpebral Aperture: Case Reports

PURPOSE

To report the use of miniscleral contact lenses (MSCLs) with diameter of 14.7 mm for Asian eyes to improve vision in patients after penetrating keratoplasty (PKP) surgery.

METHODS

Two patients with high corneal astigmatism post-PKP were evaluated for a contact lens fitting. Visual acuity, slit lamp, and anterior segment OCT findings before and after fitted the lens of 14.7 mm diameter were recorded.

RESULTS

A Kmax of case 1 and 2 were 52.8 D and 76.9 D, respectively at the first visit. Both patients were successfully fit with MSCLs, showing adequate corneal clearance of over 250 μm with no corneal touch on OCT and sufficient limbal clearance and edge alignment. MSCLs use resulted in improved comfort and visual acuity of 20/30 or better.

CONCLUSION

MSCLs with diameter of 14.7 mm can be considered a safe and effective option for patients with highly steep corneas post-PKP surgery in Asian eyes.

Comparison of penetrating keratoplasty and deep anterior lamellar keratoplasty in keratoconus eyes with vernal keratoconjunctivitis

Purpose:

The purpose of the study is to compare outcomes after penetrating keratoplasty (PK) against deep anterior lamellar keratoplasty (DALK) for keratoconus in patients with vernal keratoconjunctivitis (VKC).

Methods:

Keratoconic patients with VKC who received PK (n = 55, group 1) or DALK (n = 62, group 2) were retrospectively enrolled. The Student’s t test, Mann–Whitney test, Fisher’s exact test, chi-square test, and Kaplan–Meier survival curve were used to compare outcomes between the groups.

Results:

The follow-up period was 59.4 ± 44.1 and 62.4 ± 38.9 months in groups 1 and 2, respectively (p = 0.70). Postoperative best spectacle-corrected visual acuity was 0.24 ± 0.18 and 0.29 ± 0.19 logMAR, respectively (p = 0.13). Graft rejection occurred in 34.6% and 25.8% of eyes in groups 1 and 2, respectively (p = 0.30). Groups 1 and 2 were comparable in the rates of cataract (3.6% and 12.9%, respectively, p = 0.07) and high intraocular pressure (3.6% and 8.1%, respectively, p = 0.31). Compared with the eyes with inactive VKC, PK eyes that experienced postoperative disease reactivation had a higher rate of suture abscesses (10.9% versus 50.0%, respectively, p = 0.01) and suture-tract vascularization (6.5% versus 33.3%, respectively, p = 0.03). Similarly, disease reactivation significantly increased suture abscesses from 27.3% to 51.7% (p = 0.03) and suture-tract vascularization from 18.2% to 49.6% (p = 0.005) in the DALK group. The graft survival rates were 95.3% in group 1 and 87.9% in group 2 at the 4-year follow-up, with mean durations of 14.4 and 11.1 months, respectively (p = 0.20).

Conclusion:

The results indicate no difference in outcomes between PK and DALK for keratoconus in patients with VKC. Postoperative VKC reactivation increased the rate of suture-related problems after both techniques of keratoplasty.

Acute endophthalmitis after penetrating and endothelial keratoplasty at a tertiary eye care center over a 13-year period

Purpose:

To evaluate the clinico-microbiological profile, donor cornea risk factors, and outcomes of postkeratoplasty endophthalmitis at a tertiary care center.

Methods:

Retrospective analysis of charts of 28 consecutive patients (28 eyes) of acute endophthalmitis following either an endothelial keratoplasty (EK) or an optical penetrating keratoplasty (PK) surgery, performed between 2006 and 2018 (13-year period). Positive microbiology, identification and classification of predisposing factors, surveillance of utilized paired donors, treatment outcomes, and differences in the rate and severity of the event between optical penetrating and endothelial keratoplasty.

Results:

The estimated incidence of endophthalmitis was 0.23% in the entire cohort; it was 0.34% and 0.15%, after EK and PK, respectively (P = 0.049). The median time of endophthalmitis was 4.5 days postsurgery. Donor-related endophthalmitis was recognized in 7/28 (25%) eyes. Culture positivity was 68% (n = 19 of 28). Bacteria was isolated in 84% (n = 16 of 19) instances; Gram-negative bacilli were more common (87.5%; 14 of 16), and Pseudomonas species (50%; 7 of 14) was the most common Gram-negative bacterium. Majority (>75%) of the Gram-negative bacteria were resistant to all fluoroquinolones, aminoglycosides, 3^rd generation cephalosporins, and meropenam; 1/3^rd were resistant to imipenem; and 90% were sensitive to colistin. Treatment included intraocular antibiotic injections (96.4%), vitrectomy (42.9%), and therapeutic keratoplasty (50%). In 85.7% (24 of 28), globe was salvaged. The final vision was 20/200 or better in 39.1% (9 of 23) eyes.

Conclusion:

EK carried a higher risk of endophthalmitis than PK in this cohort. Bacterial infection was more common in this series, with Gram negative bacilli being the commonest organisms. Multidrug resistance was common (~75%) in Gram negative isolates.

Challenges in using both eyes of the same patient when evaluating the results after implantation of intrastromal corneal ring segments

PURPOSE

To assess correlation between results from both eyes of the same patient after implantation of intrastromal corneal ring segments (ICRS) and define whether they can be used together in clinical studies.

METHODS

A review of medical records of 74 patients with keratoconus implanted with bilateral Ferrara ICRS at Centro de Oftalmología Barraquer from January 2005 until December 2014. Data were collected on uncorrected visual acuity, best-corrected visual acuity and subjective refractive values (sphere, cylinder and axis).

RESULTS

A total of 39 patients were male (53%), and 35 were female (47%). Mean age at the time of implantation was 32.5 ± 10 years. No major complications occurred. A significant correlation between the results from right and left eyes was found (p < 0.0043), indicating that both eyes significantly resembled each other. No significant interaction in the magnitude of change between eye and surgery was observed under classic and mixed models.

CONCLUSION

Based on our data, whenever application is not possible under mixed-model analyses, we recommend the use of a first eye operated only, either right or left, in order to avoid bias and errors derived from autocorrelation and guarantee the independence of the registered observations.

Unexplained Bilateral Simultaneous Corneal Graft Rejection in a Healthy 18-Year-Old Male

PURPOSE

To report a rare case of unexplained bilateral corneal graft rejection one year after penetrating keratoplasty (PK) in an otherwise healthy individual, who was compliant with topical fluorometholone maintenance therapy.

OBSERVATIONS

An 18-year-old gentleman, who underwent successful, sequential, non-simultaneous, bilateral PK for advanced keratoconus, presented one year later with an acute endothelial rejection episode involving both eyes simultaneously. The rejection episode was reversed with a high dose of intravenous (IV) methylprednisolone pulse therapy over three days, topical cyclosporine-A 1%, and prednisolone acetate 1%, and then maintained on cyclosporine-A 1% eye drops, as the patient was a steroid responder. Conclusion and importance: Bilateral corneal graft rejection, although rare, can occur even several months after successful PK. Prompt management is crucial for the successful reversal of an acute corneal graft rejection episode. In steroid responders, Cyclosporine-A 1% can play a role in reducing the need for, or frequency of, potent steroid eye drops in the acute phase, and as a long-term steroid-sparing agent for maintenance.

Indications of Keratoplasty and Outcomes of Deep Anterior Lamellar Keratoplasty Compared to Penetrating Keratoplasty

Background

Corneal diseases are a significant cause of visual impairment and blindness. Despite the treatable nature of many corneal diseases before visual demise, many cases of advanced disease necessitating keratoplasty for visual rehabilitation are encountered. A mismatch between the number of corneal donors and potential recipients also exists worldwide, with underutilization of certain types of keratoplasty techniques that may allow more efficient use of this limited resource.

Methodology

A retrospective cohort study of all cases of optical corneal transplantations performed from January 1, 2015 to October 31, 2020 was performed. Indications for keratoplasty, type of keratoplasty, complications, intraocular pressure elevation, and best corrected visual acuity (BCVA) by category and range at different time intervals were collected and analyzed. Findings were compared between penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK) for all indications, specifically for keratoconus (KCN).

Results

A total of 58 corneal transplants meeting our criteria were performed during the study period. PK was performed for 29 eyes, DALK for 28 eyes, and endothelial keratoplasty for one eye. The most frequently encountered indication was KCN (62.1%). The number of eyes with BCVA of 20/100 or better increased from preoperative BCVA, 37/58 eyes had BCVA worse than 20/100 before keratoplasty (63.8%), while at the time of last follow-up 45/58 eyes had BCVA of 20/100 or better (77.6%). At the time of last follow-up 16/58 had BCVA in the range of 20/20 to 20/40 (27.6%) and 29/58 eyes had BCVA in the range of 20/50 to 20/100 (50%). Comparison of all cases of PK to DALK for all indications showed significantly better BCVA by category at one year, at last follow-up, and BCVA range at last follow-up (p = 0.032, 0.001, and 0.014, respectively). Although better visual acuity results by category and range at one year and last follow-up, respectively, were observed in more patients undergoing DALK than PK, for KCN the results were not statistically significant (p = 1.00, 1.00, 0.417, and 0.374, respectively). Overall, 70% of recorded complications, intraocular pressure (IOP) elevations, and graft rejections were seen in eyes that underwent PK; however, these findings were not statistically significant (p = 0.297). Graft failures occurred more frequently with PK than deep anterior keratoplasty when analyzed for all indications of keratoplasty (p = 0.010).

Conclusions

Despite advancement and improvements in surgical techniques, statistics continue to show underutilization of the invaluable resource of donor corneas, with PK still being performed more than DALK for diseases that do not affect the endothelium. Our study found superior visual acuity outcomes of DALK as well as the advantages of less frequent complications, IOP elevations, graft rejections, and graft failures. We encourage ophthalmologists to utilize DALK in appropriate candidates to more fully utilize the scarce and potentially vision-restoring resource of donor corneal tissue.

Corneal Pathology and Cataract: Combined Surgery or Sequential Surgery?

Objectives

To compare our combined surgery (CS) and sequential surgery (SS) results.

Materials and Methods

The files of 44 patients who underwent CS (penetrating keratoplasty [PK], cataract extraction, and intraocular lens [IOL] implantation) and 126 patients who underwent SS (cataract extraction and IOL implantation in a second session after PK) between January 2009 and December 2018 were evaluated retrospectively. One eye of the patients who were followed up for at least 1 year was included in the study. The two groups were compared in terms of indications, corrected distance visual acuity (CDVA), refractive results, complications, and graft survival.

Results

In the CS and SS groups, the median age was 63 (30-79) and 43 (18-73) years (p<0.001) and the median follow-up time was 51 (13-152) and 64.5 (13-154) months (p=0.011), respectively. The most common PK indications were traumatic corneal scar (20.5%) and endothelial dystrophy (15.9%) in the CS group versus keratoconus (24.6%) and stroma dystrophy (17.5%) in the SS group. In the CS and SS groups, 50% vs 69% of patients had CDVA ≥0.4 (p=0.04); 45.5% vs 25.4% had CDVA (0.1-0.3) (p=0.04); and 54.5% vs 73% had spherical equivalent ≤±2.0 D (p=0.02). The most common postoperative complications were glaucoma (20.5% vs 15.9%, p=0.48) and allograft reaction (9.1% vs 23%, p=0.04). Graft survival rates were 95.2% vs 86.5% (p=0.10) at 1 year and 75.9% vs 68.9% (p=0.47) at 5 years, respectively.

Conclusion

Over long-term follow-up, the groups were similar in terms of graft survival. For this reason, each patient must be evaluated separately whether to perform a combined or sequential surgery. Given the lower refractive error and higher expectation of final visual acuity, SS can be more advantageous especially in young patients.

[Anterior stromal micropuncture for the treatment of persistent corneal epithelial graft defects after penetrating keratoplasty]

Persistent corneal graft erosion or persistent epithelial corneal defect is a frequent complication of penetrating keratoplasty. Its development can be contributed by the dry eye syndrome, rare blinking, lagophthalmos, symblepharon, viral infection, autoimmune aggression, and the use of epithelial-toxic eye drops. The article presents three clinical observations of patients who developed persistent corneal graft erosion after penetrating keratoplasty. Due to the ineffectiveness of local conservative therapy for more than 3 weeks, anterior stromal corneal micropuncture was performed. After the procedure, there was a gradual epithelial proliferation, complete healing of the corneal surface was observed 10-16 days after the manipulation, the follow-up period was at least 1 year. The mechanism of action of stromal micropuncture is associated with the creation of a porous surface with better adhesion properties, as well as with the activation of the production of extracellular matrix glycoproteins such as fibronectin, type IV collagen and laminin, which are necessary for stable adhesion of the epithelium. The use of stromal micropuncture of the donor flap in the treatment of post-keratoplasty persistent corneal epithelial defect was proposed for the first time.

Clinical Characteristics and Outcomes of Short-term Repeat Corneal Transplantation

PURPOSE

To explore the primary indications, direct causes and graft survival of short-term repeat keratoplasty.

METHODS

An analytical cross-sectional study.

RESULTS

The primary indications for keratoplasty were infectious keratitis (67.9%) and immune keratopathy (12.8%). The direct causes of graft failure were infectious ulcer (43.6%) and recurrence (30.8%). Pre-operative hypopyon (P = 0.017, HR = 1.757) and use of decellularized porcine corneas as grafts (P = 0.005, HR = 2.690) were independent risk factors for graft failure. The Kaplan-Meier analysis revealed that the 1-year survival rate of 88 repeat grafts was 85.2%, and the 5-year survival rate was 79.2%. The survival rates of the repeat grafts were significantly higher than those of the first grafts (P < 0.001).

CONCLUSION

Infectious keratitis is the most common indication of short-term graft failure and is often failed by infectious ulcer and keratitis recurrence. While the decellularized porcine cornea is a promising application in developing countries, certain difficulties, such as graft melting, remain unresolved.

Pediatric keratoconus - Current perspectives and clinical challenges

Keratoconus is an ectatic corneal disease characterized by progressive stromal thinning, irregular astigmatism, and defective vision. It can be unilateral or bilateral with asymmetric presentation. It starts at puberty and either progresses rapidly to an advanced stage of the disease or stops in case of delayed onset and slow progression. Pediatric keratoconus is more aggressive than in adults and the management protocols differ because of various rationales such as accelerated progression, advanced stage of disease at the time of diagnosis and co-morbidities. It poses a burden to the society as it affects the quality of life, social, and educational development in children. Hence early diagnosis, recognition of progression, and timely intervention with collagen crosslinking is imperative to arrest the worsening. Association with systemic syndromes and ocular comorbidities can be of concern in pediatric keratoconus. Severe ocular allergy when associated hastens progress and complicates timely intervention of crosslinking treatment and compliance to contact lens wear. Keratoplasty in pediatric keratoconus has good outcomes but can encounter frequent suture-related concerns. This article discusses the epidemiology, etiopathogenesis, clinical challenges, and current perspectives of management of pediatric keratoconus.

Impact of Scleral Contact Lens Use on the Rate of Corneal Transplantation for Keratoconus

PURPOSE

To evaluate the association of scleral contact lens (SCL) use on the risk for keratoplasty for people with keratoconus.

METHODS

The electronic health records of patients receiving eye care at the University of Michigan Kellogg Eye Center between August 1, 2012, and December 31, 2018, were reviewed. Patients with a diagnostic code of keratoconus or corneal ectasia, no previous history of keratoplasty, and for whom data were available for both eyes were included. Using a multivariable Cox regression model, associations between SCL use and keratoplasty were tested and adjusted for sociodemographic factors, maximum keratometry, and current contact lens (CL) use.

RESULTS

Two thousand eight hundred six eyes met the inclusion criteria. CL use in each eye was 36.2% with no CL, 7.2% soft, 33.9% rigid gas permeable (RGP), and 22.7% scleral. A total of 3.2% of eyes underwent keratoplasty. In the adjusted model, SCL or RGP CL use significantly lowered the hazard of undergoing keratoplasty (HR = 0.19, 95% confidence interval [CI] 0.09-0.39, P < 0.0001 and HR = 0.30, 95% CI 0.17-0.52, P < 0.0001, respectively) when compared with no CL use. Factors associated with increased risk of keratoplasty were black race as compared to white (HR = 1.87, 95% CI 1.10-3.16, P = 0.02), younger age (HR = 0.92 per 5-year increment, 95% CI 0.86-0.99, P = 0.032), and lower socioeconomic status (HR = 1.08 per 5-point increase in the Area Deprivation Index, 95% CI 1.03-1.13, P = 0.0008). Keratoplasty was not associated with sex, insurance, or maximum keratometry.

CONCLUSIONS

Physicians should maximize the use of scleral or RGP CL because patients who successfully use CL have almost one-fifth the risk of undergoing keratoplasty.

Corneal Graft Success Rates in HSV Keratitis: A Systematic Review

Herpes Simplex Virus (HSV) has worldwide prevalence. The primary objective of this systematic review was to compare penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK) regarding the efficacy and complications of the treatment of corneal scarring caused by herpes simplex keratitis. Out of the 469 articles identified during the combined search of the literature based on the PubMed and Cochrane libraries, 10 retrospective and 2 prospective studies published from January 2010 to December 2019 were included. The study outcomes indicated that both surgical approaches resulted in a comparable improvement of visual acuity (VA). However, DALK demonstrated fewer complications in the majority of studies. Higher graft survival rates were associated with higher acyclovir (ACV) doses (above 800 mg/day), topical steroid and antibiotic drops. In conclusion, in terms of postoperative VA, both PK and DALK demonstrate comparable efficacy. However, DALK, which is applied in less severe HSK cases, is associated with fewer complications and better graft survival rates. High dosages of ACV, topical steroids and antibiotics contribute significantly to improved postoperative outcomes.