Visual Outcomes and Prognostic Factors of Successful Penetrating Keratoplasty in 0- to 7-Year-Old Children With Congenital Corneal Opacities

Clinical Analysis of Repeat Penetrating Keratoplasty in Children

(1) Background: To analyze the indications, graft survival, and graft failure-related risk factors of repeat penetrating keratoplasty (RPK) in children. (2) Methods: In this case series, children younger than 12 years who received RPK at Beijing Tongren Hospital were reviewed. The indications for RPK, postoperative complications, and graft survival were analyzed. The analysis of the potential variables associated with graft survival was performed using Cox proportional hazards regression. (3) Results: A total of 30 RPK eyes of 29 children were included in this study. The mean follow-up time was 26.98 ± 18.75 months. The most common indication for RPK was a vascularized corneal scar (86.67%). Postoperative complications occurred in 27 eyes (90%), including immune rejection (46.67%), epithelial defects (36.67%), and glaucoma (26.67%). About 60% of the regrafts remained clear one year after RPK, while the overall graft survival rate was 30% at the last visit. The most common cause of regraft failure was irreversible immune rejection (8/21). The significant risks of graft failure included an age of less than 60 months at surgery (p = 0.009), corneal vascularization (p = 0.018), and a postoperative epithelial defect (p = 0.037). (4) Conclusions: A vascularized corneal scar is the most common indication of RPK in children. Immune rejection is the most prevalent complication, and irreversible immune rejection always causes regraft failure.

Update on Pediatric Corneal Diseases and Keratoplasty

Managing pediatric corneal disorders is challenging as the prognosis of pediatric keratoplasty depends on several factors. Advancements in the genetic basis of congenital corneal diseases and investigations in congenital corneal conditions provide a better understanding of pediatric corneal conditions. Surgeons performing keratoplasty in children now have a choice of various techniques. Evolving surgical techniques of anterior lamellar and endothelial keratoplasties has expanded the management interventions in these pediatric corneal morbidity conditions; however, considerable concerns still exist in association with corneal transplantation in infants and children. Outcomes in pediatric keratoplasty depend upon the preoperative indications, the timing of surgical intervention, intraoperative and postoperative factors including the patient/care givers' compliance. Factors such as low scleral rigidity, higher rate of graft failure, need for frequent examinations under anesthesia, and difficulty in optimal visual acuity assessment still remain a considerable challenge in pediatric scenarios. In children, deprivation amblyopia as a result of the corneal opacification can adversely affect visual development, causing dense amblyopia. Outcomes to surgical interventions for management of corneal opacification in children is further compromised by the pre-existing amblyopia apart from the concerns of refractive outcome of the graft. Graft rejection, graft infection, amblyopia, and glaucoma continue to be serious concerns. In recent years both anterior and posterior lamellar keratoplasty techniques are being increasingly performed in pediatric eyes, which offer advantages in the form of lower risk of graft rejection. The timing of surgery, careful case selection, cautious intraoperative approach, and optimal postoperative management can improve the anatomical and functional outcome in difficult cases.

[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.

Current Perspectives on Corneal Transplantation (Part 2)

Disease of the cornea is the third leading cause of blindness worldwide. Corneal graft surgery is one of the most successful forms of solid organ transplantations in humans, with ever increasing developments in surgical technique. To date, approximately 4504 corneal transplants are performed in the UK each year. While full thickness transplantation was the most commonly performed keratoplasty over the last few decades, selective lamellar transplantation of the diseased layers of the cornea has been universally adopted. This comprehensive review aims to provide an updated synthesis on different types of corneal transplantations, their treatment outcomes, and the associated complications of each procedure both in adult and pediatric populations. In addition, we also present an up-to-date summary of the emerging therapeutic approaches that have the potential to reduce the demand for donor-dependent keratoplasty.

Penetrating keratoplasty in children under 3 years old with congenital corneal opacities

AIM

To evaluate the graft rejection and visual outcomes after penetrating keratoplasty (PK) in the presence of various congenital corneal opacities in children.

METHODS

In this retrospective cohort study, children who underwent PK were then followed for 5y. The patient's medical records were collected from June 2014 until June 2019 and analyzed in December 2019. All patients were children under three years old with congenital corneal opacities with or without microcornea who came to a pediatric ophthalmologist and underwent PK in Jakarta Eye Center (JEC). Beforehand, all children have participated in a thorough evaluation for PK. In the case of severe microcornea was not advised to undergo surgery. The visual outcomes and graft survival rate were described in percentages. The graft survival plot was presented with Kaplan-Meier, while the visual acuity was analyzed using the Wilcoxon signed ranks test.

RESULTS

Sixteen eyes from eleven patients (seven girls and four boys) underwent PK. The graft survival rate of the first 6, 12, and 18 mo later of keratoplasty was 100%, 83.3%, and 66.7%, respectively. The overall mean survival time is 22mo (standard error 2.419), and no significant difference between the patients underwent PK before and after 36mo of their age (P=0.52). The graft failure was 50%, and post-surgery complications included cataract 43.7%, band keratopathy 12.5%, and scleromalasia 6.25%. Wilcoxon test analysis of visual acuity post keratoplasty was not statistically significant (P=0.34), while overall showed 44% improvements of visual outcome for 5y of follow-up. With a good survival at one year up to 22mo (83.3%), the visual acuity could be achieved (63%), and showed improvements (44%) during follow-up.

CONCLUSION

The complications are frequent for pediatric PK. Thus, corneal surgery on infants requires careful case selection, adequate pre-operative evaluation, skilled surgery (optical correction), very close cooperation family-physician, intensive post-operation care, and amblyopia management in the future.

Possible association between viral infection and poor survival of the corneal graft after penetrating keratoplasty in patients with congenital corneal opacity: a cohort study

BACKGROUND

Congenital corneal opacity (CCO) is a rare disorder. Penetrating keratoplasty (PK) is the main surgical option for CCO, but many factors affect graft survival. Therefore, this study aimed to perform a virological examination of CCO specimens after PK to explore the relationship between virological factors and graft survival after PK.

METHODS

This prospective study included consecutive patients (<6 months of age) diagnosed with CCO and treated with PK at Beijing Tongren Hospital from August 2017 to January 2018. Next-generation sequencing was used to detect viral DNA in the CCO specimens. The survival of the primary graft was analysed using the Kaplan-Meier method.

RESULTS

Overall, 24 eyes of 24 infants were treated with PK during the study period. The mean age at surgery was 4.8±1.1 months. Epstein-Barr virus DNA was detected in two specimens, varicella-zoster virus DNA in one specimen, herpes simplex virus DNA in three specimens and cytomegalovirus DNA in one specimen. In the virus-positive group, only one (14.3%) graft remained clear during follow-up. In contrast, in the virus-negative group (n=17), 13 (76.5%) grafts were still clear at the last follow-up. The mean survival of the grafts in the virus-positive group was significantly shorter than in the virus-negative group (11.0±9.8 months vs 27.1±7.7, p<0.001).

CONCLUSION

The presence of viral DNA in CCO specimens might be associated with poor graft survival after PK.

Analysis of Graft Failure After Primary Penetrating Keratoplasty in Children With Peters Anomaly

PURPOSE

To investigate the causes of graft failure and risk factors associated with total graft opacity after primary penetrating keratoplasty (PK) in children with Peters anomaly (PA).

METHODS

In this retrospective study, patients with PA (younger than 5 years) who received primary PK in Beijing Tongren Hospital were reviewed. The follow-up period was a minimum of 6 months. A modified PA classification system was used, and all failed grafts were categorized into partial and total opacity groups. Patient demographics, PA classification, operation details, degree of graft opacity, and causes of graft failure were recorded.

RESULTS

Of the 165 eyes, 54 eyes (32.7%) demonstrated graft failure along with various degrees of graft opacity. Approximately half of the grafts applied failed within 6 months postoperatively. The partial and total opacity groups did not demonstrate any significant differences regarding diagnosis distribution. Irreversible immune rejection accounted for 61.1% of all graft failures; furthermore, it had a significantly higher proportion in the partial opacity group than in the total opacity group (71.0% and 47.8%, respectively; P = 0.058). The degree of graft opacity was significantly associated with patient age at surgery (P = 0.002), preoperative corneal vascularization (P = 0.009), and iris defects (P = 0.001). However, administration of intensive topical corticosteroids could reduce the risk of total opacity in the rejected grafts.

CONCLUSIONS

Irreversible immune rejection is the most common cause of graft failure after primary PK in pediatric patients with PA. The degree of graft opacity is closely related to patient age at surgery, preoperative corneal vascularization, and iris defects.

Penetrating Keratoplasty in Infants With Peters Anomaly: Visual and Graft Outcomes

PURPOSE

To determine the prevalence of survival of corneal grafts and visual outcomes of primary penetrating keratoplasty (PK) in infants with Peters anomaly (PA) in Beijing, China.

METHODS

Twenty-nine patients (37 eyes) with PA who underwent PK before the age of 1 year were included. Optical correction for all eyes and occlusion therapy of amblyopia for a unilateral opacity were performed 2 weeks after suture removal. All infants underwent assessment of visual acuity after surgery using Teller Acuity Cards. Survival probabilities were estimated using the Kaplan-Meier method and log-rank test. Visual outcomes and prognosis factors were analyzed using the χ2 test.

RESULTS

The mean age of 29 infants undergoing primary PK was 5.7 ± 2.3 months. The mean follow-up duration was 18.0 ± 3.0 months. Twenty-seven (73.0%) of 37 grafts retained full clarity at final follow-up. Visual acuity above ambulatory was achieved in 67.6% (25/37) and >20/260 was achieved in 48.6% (18/37) of cases. Of all surgical indications, vascularized PA I (50.0%, 6/12) and PA II (18.2%, 2/11) showed a lower proportion achieving visual acuity >20/260 than nonvascularized PA I (71.4%, 10/14) (P = 0.030 < 0.05). There was no significant difference in the prevalence of graft survival and vision outcome between infants younger than 6 months and older than >6 months.

CONCLUSIONS

For infants with PA who underwent PK, the prevalence of graft survival and visual acuity were related mainly to the indication. The main risk factors were corneal vascularization and an abnormal lens.

Pediatric Keratoplasty: The Success of a Tailor-Made Surgical Management

A Romanian 5-month-old girl was referred to our hospital after being diagnosed with congenital corneal opacities. She was sent in order to undergo penetrating keratoplasty (PKP) surgery on her left eye. The patient presented a natural tendency to esotropia. We took into account two different surgical techniques: PKP and lamellar keratoplasty. The latter was technically impossible to carry out because of the full-thickness corneal opacity. We conducted several tests to accurately obtain the patient's preoperative parameters and specifically decide the details of the surgical technique to be applied. For each step of the surgical procedure we carefully compared the individual results in the literature in order to ensure a stable and lasting result. In addition to this, we used an innovative suture technique: nylon thread, interrupted suture, alternating 11-0/10-0 threads. Six months after the operation, the functional result obtained was 4–5/10, with recovery of the fixation. Pediatric PKP, therefore, cannot follow a surgical standard, but requires careful case-by-case evaluation from the pre- to the postoperative phase, with the aim of maximizing stable visual acuity.

Outcome of a penetrating keratoplasty in a 3-month-old child with sclerocornea

Sclerocornea is a rare congenital anomaly with clouding of the peripheral cornea that possibly extends up to the center of the cornea. Characteristically, a clear distinction (limbus) between sclera and cornea is lacking. Early surgical treatment is essential for preventing amblyopia, but penetrating keratoplasty in children carries a relatively high risk of complications. Especially for sclerocornea, penetrating keratoplasty has generally been reported to have a poor surgical outcome and a high risk of complications, including corneoscleral adhesions. Here, we report the 4-year follow-up on a child with sclerocornea, who was successfully operated on at the age of 3 months and had a favorable outcome. Our findings suggest that in some cases, penetrating keratoplasty may be an option to treat sclerocornea in young children.

[Keratoplasty in children : Indications and results]

Penetrating keratoplasty in children is associated with very specific difficulties for the surgeon as well as for the patient and the parents. Special features are specific pediatric indications, which do not occur in adults, a more difficult examination and treatment adherence depending on the parents. Diseases with a favorable prognosis include keratoconus and herpetic keratitis. Especially sclerocornea and the Peters' anomaly often have a limited prognosis regarding vision and graft survival due to secondary malformations of the eye. In addition, younger age represents a risk factor. This is most likely due to the impaired examination during follow-up and reduced compliance. For successful penetrating keratoplasty in children the timing for the operation, in which the risk for the graft is weighed up against the risk for amblyopia, is crucial.