"Swiss roll" amniotic membrane technique for the management of corneal perforations

Banking of post-SMILE stromal lenticules for additive keratoplasty: A new challenge for eye banks?

PURPOSE

ReLEx (Refractive Lenticule Extraction) Small Incision Lenticule Extraction (SMILE), the second generation of ReLEx Femtosecond Lenticule Extraction (FLEx), is a minimally invasive, flapless procedure designed to treat refractive errors such as myopia, hyperopia, presbyopia, and astigmatism. This review aims to provide a comprehensive overview of the methods for preserving SMILE-derived lenticules and discusses their potential future applications.

METHODS

A narrative literature review was conducted using PubMed, Scopus, and Web of Science databases, focusing on articles published up to January 2024 and available in English. The authors also evaluated the reference lists of the collected papers to identify any additional relevant research.

RESULTS

No standardized protocols currently exist for the storage or clinical application of SMILE-derived lenticules. However, these lenticules present a promising resource for therapeutic uses, particularly in addressing the shortage of donor corneal tissues. Their potential applications include inlay and overlay additive keratoplasty, as well as other ocular surface applications. Further research is needed to establish reliable protocols for their preservation and clinical use.

CONCLUSION

SMILE-derived lenticules offer significant potential as an alternative to donor corneal tissues. Standardizing their storage and application methods could enhance their use in clinical settings.

Corneal stromal lenticule transplantation for the treatment of corneal ulcers

PURPOSE

To evaluate the safety and efficacy of using corneal stromal lenticules (CSLs) obtained during refractive surgery Refractive Lenticule Extraction (ReLEx) with the Small Incision Lenticule Extraction (SMILE) procedure for the treatment of corneal ulcers.

METHODS

This retrospective study included 12 eyes of 12 patients, 7 men and 5 women with varying degrees of corneal ulcer. The mean age was 64 ± 18 (range 34 to 95 years). The monitoring included corrected distance visual acuity (CDVA), slit-lamp biomicroscopy examination, a Seidel test, stability of the graft and anterior segment optical coherence tomography (AS-OCT) inspection. Patients were closely monitored for possible postoperative complications for at least 6 months.

RESULTS

In 7/12 (58%) eyes, the corneal ulcer was successfully sealed with CSL and amniotic membrane (AM) without the need for any additional surgical intervention. In 3 eyes, penetrating keratoplasty (PK) was needed in addition to CSL transplantation and in 2 eyes the scleral patch was used to fully seal after CSL transplantation. During the follow-up period no signs of rejection or infection were detected in any patient.

CONCLUSION

The use of CSLs from ReLEx SMILE may be considered as an alternative method for the treatment of corneal ulcers before a more extensive and definitive solution - PK - is used. Our preliminary findings suggest that properly performed CSL transplantation using cryopreserved lenticules is a safe and effective method to temporarily cover the corneal partial-thickness defect or even perforation.

Case Report: Use of Amniotic Membrane for Tectonic Repair of Peripheral Ulcerative Keratitis With Corneal Perforation

Purpose

To provide a perspective and surgical video demonstration of peripheral corneal ulceration and perforation managed with multilayered amniotic membrane transplantation.

Case Reports

Case 1 describes a 48-year-old female with progressive redness and pain, and an inferonasal corneal thinning and perforation in the left eye from peripheral ulcerative keratitis. She underwent conjunctival recession with amniotic membrane inlay and onlay (Sandwich technique) transplantation. The amniotic membrane integrated well, and her Snellen visual acuity improved from 6/21 preoperatively to 6/9 at 3 months post op. Case 2 describes a 78-year-old male with redness and pain with temporal corneal thinning bilaterally and perforation in the right eye from peripheral ulcerative keratitis. Both eyes underwent similar surgical intervention with smooth integration of the amniotic membrane in the cornea and improvement in the visual acuity. Both patients were also started on systemic immunosuppression in collaboration with the rheumatology team.

Conclusion

We report successful use of multilayered amniotic membrane transplantation for the treatment of corneal ulceration and perforation. The authors believe the simplicity of the surgical technique, easier access to amniotic membrane tissue, and lower induced post-operative astigmatism all provide advantages over alternative treatment modalities.

Sutureless Tectonic Mini-Descemet's Stripping Automated Endothelial Keratoplasty ("mini-DSAEK") for the management of corneal perforations

PURPOSE

To report the outcomes of a new technique, pull-through sutureless 'mini-DSAEK', to manage corneal perforations secondary to different aetiologies including trauma, neurotrophic ulcer following penetrating keratoplasty (PK), herpes simplex keratitis and microbial keratitis.

METHODS

In this retrospective case series, we report the clinical outcomes of five cases of sutureless tectonic mini-DSAEK performed in patients presenting with large corneal perforations to Southend University Hospital between November 2019 and October 2020. One corneal perforation was sufficiently peripheral for the tectonic mini-DSAEK graft to be successfully positioned outside of the central visual axis. Four corneal perforations were central or paracentral for which the tectonic grafts involved the visual axis.

RESULTS

Anterior chambers remained deep and formed with no evidence of leak in all subsequent follow ups in all patients representing 100% tectonic success. All tectonic grafts remained attached except one partially detached graft. One patient underwent uneventful phacoemulsification with intraocular lens implant 8 months after the primary intervention with excellent visual outcome. Two patients underwent two-piece mushroom PK and one patient underwent triple procedure (cataract extraction   +   intraocular lens   +   PK) for visual rehabilitation 2-6 months after the primary intervention with good visual outcome.

CONCLUSION

Sutureless tectonic pull-through mini-DSAEK is a useful technique in the management of corneal perforations, with a number of advantages compared with conventional techniques.

Results of Resorbable and Running Sutured Amniotic Multilayers in Sterile Deep Corneal Ulcers and Perforations

PURPOSE

To present the results of a modified surgical technique for secure tightening and fixation of multilayer amniotic membranes (AMs) in sterile deep or perforating corneal ulcers.

METHODS

We retrospectively analyzed the data of patients suffering from corneal ulcers who had been treated between February 2016 and June 2018 with running and resorbable sutures to fixate multilayer AMs. The parameters analyzed were gender, age, etiology of corneal ulcer, ulcer diameter, corneal thickness (CST) before and after the microsurgical procedure as measured with optical coherence tomography, number of inlays, repeat surgical procedures, follow-up duration in months, and rate of success (defined as a stable anterior chamber with improved CST, a negative Seidel test, and no need for any microsurgical keratoplasty during the first 6 months after treatment). The results were statistically evaluated using the Wilcoxon test. A P-value ≤0.05 was considered to show a statistically significant difference.

RESULTS

The CST increased significantly after AM transplantation (from 206.26 ± 114.93 μm at baseline to 454.70 ± 244.08 μm at 1-3 months; P < 0.001). Repeat multilayer transplantation was required in 7 of the 23 patients included (30.4%), in 6 of whom the treated eye was stable at month 6. In 2 of the 23 patients, perforating keratoplasty became necessary. One patient also demanded such a procedure to improve his visual acuity. The success rate was 91.3% (n = 21).

CONCLUSIONS

Running resorbable suture fixation of multilayer AMs proved to be an efficient means for the treatment of noninfectious deep or small perforating corneal ulcers.

Tectonic Mini-DSAEK Facilitates Closure of Corneal Perforation in Eyes With Healthy Endothelium

PURPOSE

The purpose of this study was to report a surgical technique for closure of a traumatic corneal perforation in a patient with healthy endothelium.

METHODS

A 69-year-old male patient presented to Southend University Hospital with a 2.5 mm round temporal corneal perforation caused by a metallic foreign body from an industrial accident. Best-corrected visual acuity at presentation was 6/36. The patient received a tectonic small diameter Descemet stripping automated endothelial keratoplasty (mini-DSAEK) to close the perforation. The patient subsequently developed traumatic cataract and underwent cataract surgery 8 months later. Clinical outcomes at 1 week, 1 month, 3 months, 6 months, and 9 months were evaluated. The primary outcomes of interest were successful sustained closure of the perforation and surgical complications, with secondary outcomes of best-spectacle corrected visual acuity (BSCVA, Snellen) and keratometric astigmatism (KA, Pentacam).

RESULTS

The anterior chamber was reformed by the graft, restoring the globe's mechanical integrity. The bare stroma reepithelized by 1 week. Neither intraoperative nor postoperative surgical complications were reported. The anterior chamber remained deep and formed during subsequent follow-ups through 9 months. At the 9-month follow-up, final best spectacle-corrected visual acuity was 6/6-1 (Snellen fraction). Keratometric astigmatism was 1.1 diopters.

CONCLUSIONS

Tectonic mini-Descemet stripping automated endothelial keratoplasty is a safe technique in the management of corneal perforations too large for tissue adhesives, with a low astigmatic profile and rapid visual recovery.

Ultra-stiff compressed collagen for corneal perforation patch graft realized by in situ photochemical crosslinking

Despite the potential of a collagen construct, consisting of a major extracellular matrix component of the native cornea, as a patch graft to treat the corneal perforation, there has still been difficulty in acquiring sufficient mechanical properties for clinical availability. This study developed a novel in situ photochemical crosslinking (IPC)-assisted collagen compression process, namely, the IPC-C² process, to significantly enhance the mechanical properties of the collagen construct for the development of a collagenous patch graft. For the first time, we found that compressed collagen construct was rapidly rehydrated in an aqueous solution, which inhibited effective riboflavin-mediated photochemical crosslinking for mechanical improvement. The IPC-C² process was designed to concurrently induce the physical compaction and photochemical crosslinking of a compressed collagen construct, thereby avoiding the loosening of collagen fibrillar structure during rehydration and ultimately improving crosslinking efficiency. Hence, the suggested IPC-C² process could fabricate a collagen construct with a high collagen density (∼120-280 mg ml^-1) and ∼10³-fold increased mechanical properties (an elastic modulus of up to ∼29 MPa and ultimate tensile strength of ∼8 MPa) compared with collagen gel. This construct can then be used as a clinically applicable collagenous patch graft. With sufficient mechanical strength for surgical suture and the controllable thickness for patient specificity, the potential of the fabricated IPC-compressed collagen construct for clinical applications was demonstrated by using an in vivo rabbit corneal perforation model. It effectively protected aqueous humor leakage and maintained the integrity of the eye globe without an additional complication.

Case Series Describing the Use of Low-Temperature Vacuum-Dehydrated Amnion (Omnigen) for the Treatment of Corneal Ulcers in Cats and Dogs: 46 Cases (2016-2017)

Amniotic membrane is widely used in the treatment of ocular surface disorders in human and veterinary patients. Preservation and storage of amnion has proven challenging, prompting the development of new preservation techniques. Omnigen, a novel low-temperature vacuum-dehydrated amnion, is reported to possess enhanced structural properties and biochemical stability in vitro, but its clinical use in veterinary patients is not well described. This study aims to document and describe the varied use of Omnigen for the surgical treatment of corneal ulceration in cats and dogs. A total of 45 patients (46 eyes) were recruited from the clinical record system of the Royal Veterinary College (London) between January 2016 and December 2017. Brachycephalic breeds were over-represented (37/45; 82.2%). Omnigen was used as a standalone graft in 5/46 (10.9%) eyes, as a supplementary graft in 29/46 (63.0%) eyes and as a patch in 12/46 (26.1%) eyes. Graft failure occurred in 10/46 eyes (21.7%). At final examination 43/46 eyes (93.5%) had healed and 31/33 eyes (93.9%) were visual. This study demonstrates the successful use of Omnigen for the surgical treatment of corneal ulceration in cats and dogs. Further studies are needed to clarify its properties and benefits in the clinical field.

Lamellar Keratoplasty Combined with Amniotic Membrane Transplantation for the Treatment of Corneal Perforations: A Clinical and In Vivo Confocal Microscopy Study

Purpose

To evaluate the clinical and in vivo confocal microscopy outcome of lamellar keratoplasty combined with amniotic membrane transplantation for the treatment of corneal perforations.

Methods

In this retrospective, noncomparative, and interventional case series, 13 eyes of 13 patients with corneal perforation were included. All eyes were treated with lamellar keratoplasty combined with amniotic membrane transplantation for corneal reconstruction. Age, underlying etiology, location, size of corneal ulcer, size of corneal perforation, hospitalization days and follow-up time, and corneal confocal microscopy were investigated. Aqueous leakage, anterior chamber formation, epithelial healing time, and visual acuity (VA) were monitored after operation.

Results

The cause of corneal perforation (n = 13) was classified as infectious (n = 13) was classified as infectious (n = 13) was classified as infectious (

Conclusion

Lamellar keratoplasty combined with amniotic membrane transplantation may be an alternative, safe, and effective surgical therapy in the treatment of corneal perforations in the absence of a fresh donor cornea. We recommend this surgery to treat with the size of corneal perforation of <4 mm in diameter no matter peripheral or central corneal perforation, especially who had immune-related diseases.

Amniotic Membrane as a Main Component in Treatments Supporting Healing and Patch Grafts in Corneal Melting and Perforations

Purpose

To report on surgical approaches using amniotic membrane applications and patch grafts in corneal melting and perforations. Anatomical and functional results, including advantages and disadvantages of the interventions, will also be explored.

Methods

A five-year retrospective analysis of 189 surgical treatments involving corneal melting with perforation was performed. In one evaluated treatment type, a graft of amniotic membrane, often folded one to three times, was sutured with the epithelial side facing the previously mechanically debrided corneal tissue. A larger monolayer amniotic patch was then sutured, with the epithelial side facing the top of the first membrane, to the perilimbal conjunctiva. For corneal patch grafts, the size-fitting technique of graft trephination was applied, and the donor-recipient junctions were sewn with interrupted sutures. All the procedures were evaluated, noting outcomes and complications of surgery, preoperative and postoperative visual acuities, postoperative intraocular pressures, graft rejection, and other late comorbidities and complications.

Results

We performed 119 amniotic membrane applications (63%) and 70 corneal patch grafts (37%). Anatomical reconstruction of the anterior chamber was achieved in 157 eyes, of which 102 eyes (86%) received an amniotic membrane and 55 eyes (79%) were treated with the patch graft technique. In 63 eyes (33%), more than one amnion or graft treatment was necessary to close the corneal perforation.

Conclusions

The success of medical and surgical management depends on the cause of corneal melting, and amniotic membrane applications often require further intervention; nevertheless, patch grafts deliver better tectonic reconstruction than amniotic membrane alone.

Resorbable and running suture for stable fixation of amniotic membrane multilayers: A useful modification in deep or perforating sterile corneal ulcers

Purpose

To present a modified technique for secure tightening and fixing of multilayer amniotic membranes in deep or perforating corneal ulcers.

Observations

The modified procedure for application and fixation of multilayer amniotic membranes is retrospectively described step by step, and the results of three patients treated with this technique were retrospectively analysed and presented.

The modification consists basically in fixing the inlays with one mini-overlay that is sutured intracorneally with resorbable and running Vicryl 10.0, before a corneoscleral overlay is fixed on top conjunctivally with a running nylon 10.0 suture. The resorbable Vicryl suture is left in place permanently.

Conclusions and Importance

The method described avoids any risk of destroying or displacing the inlays by removing sutures later. In each of the three patients demonstrated as case reports the cornea remained stable throughout the 3- to 5-month follow-up period. This modified technique represents a very useful auxiliary means of treating deep or perforating non-infectious corneal ulcers.

Stromal lenticule transplantation for management of corneal perforations; one year results

PURPOSE

To study application of stromal lenticules extracted by femtolaser small incision lenticule extraction (SMILE) surgery as a surgical adjuvant to seal corneal perforations.

METHODS

Corneal stromal lenticules obtained through SMILE surgery with central thickness 100 μm or more were fixed over corneal perforation sites using 10-0 nylon interrupted stitches with an overlying single layer of amniotic membrane. Seven patients who had been followed up for a minimum of 12 months were assessed using slit-lamp biomicroscopy, fluorescein stain, tonometry, and best spectacle-corrected visual acuity (BSCVA) measurements. Postoperative complications were recorded throughout the follow up period.

RESULTS

Corneal perforations had successfully been sealed in all 7 patients; 3 patients (42.9%) exhibited improved postoperative BSCVA. During the follow-up period of one year, no signs of re-perforation or infections were detected in any patient.

CONCLUSIONS

These early findings suggest that the use of corneal stromal lenticules could be a safe and efficient surgical adjuvant for corneal perforation closure with potential clinical application, together with amniotic membrane, as relatively simple and low cost temporary measures to prepare perforated corneas for further definitive procedures.

Improvement of Amniotic Membrane Method for the Treatment of Corneal Perforation

In our retrospective study we evaluated the efficacy of an improved amniotic membrane (AM) roll-in filling technique (AMR) combined with multilayer amniotic membrane cover to treat corneal perforation and included 46 cornea perforations ≤ 3 mm in diameter treated with AMR and 20% C₃F₈ mixed gas filling of the anterior chamber. Anterior chamber depth, aqueous leakage, bubble maintenance time, and cornea morphology were monitored after each operation. The mean diameter of corneal perforation was 1.60 ± 0.55 mm (range 0.5–3) and the success rate of the AMR method for corneal perforation reconstruction was 100% after a single operation. Anterior chamber depth was normally reconstructed without AMR break-off, aqueous leak, or other complications. The mean time of the C₃F₈ gas bubble in the anterior chamber was 8.6 ± 2.0 days (range 4–12). At the last follow-up, all patients' visual acuity was improved to varying degrees. The mean follow-up time was 11.0 ± 5.6 months (range 3–36). The AMR plugging combined with multilayer AM cover is a secure and easy intervention, which led to 100% success in our study. Various perforations ranging from trauma to infection can be treated with AMR, which is especially practical in those countries where donor cornea availability is limited.

Treatment of corneal perforation with lenticules from small incision lenticule extraction surgery: a preliminary study of 6 patients

PURPOSE

To evaluate the use of lenticules extracted using small incision lenticule extraction (SMILE) surgery as a surgical alternative for wound closure in corneal perforation.

METHODS

Corneal lenticules obtained through SMILE surgery with central thickness >100 μm were fixed over corneal perforation sites using 10-0 nylon interrupted stitches. Patients were monitored for a minimum of 1 year and were assessed using slit-lamp microscopy, fluorescein, digital tonometry, and best spectacle-corrected visual acuity (BSCVA) measurements. Postoperative complications throughout the study period were recorded.

RESULTS

Corneal perforations were successfully sealed in all 6 patients; 3 patients (50%) exhibited improved postoperative BSCVA. Between 3 and 4 weeks after the operation, part of the lenticules became incorporated into the corneal stroma and complete reepithelialization was achieved. During the follow-up period of 12 months, no evidence of infection, relapse, or perforation was detected in any patient.

CONCLUSIONS

These preliminary findings suggest that the use of corneal lenticules may be a safe and effective surgical alternative for corneal perforation closure, with potential clinical application as relatively simple and inexpensive temporary measures to improve the condition of the cornea for further definitive interventions.

Tectonic DSAEK for the Management of Impending Corneal Perforation

Purpose. To report a case of severe corneal thinning secondary to dry eye treated with a tectonic Descemet stripping automated lamellar keratoplasty (DSAEK) and amniotic membrane graft. Methods. A 72-year-old man with a history of long standing diabetes mellitus type 2 and dry eye presented with 80% corneal thinning and edema on the right eye and no signs of infectious disease, initially managed with topical unpreserved lubrication and 20% autologous serum drops. Eight weeks after, the defect advanced in size and depth until Descemetocele was formed. Thereafter, he underwent DSAEK for tectonic purposes. One month after the procedure, the posterior lamellar graft was well adhered but a 4 mm epithelial defect was still present. A multilayered amniotic membrane graft was then performed. Results. Ocular surface healed quickly and reepithelization occurred over a 2-week period. Eight months after, the ocular surface remained stable and structurally adequate. Conclusion. Tectonic DSAEK in conjunction with multilayered amniotic graft may not only provide structural support and avoid corneal perforation, but may also promote reepithelization and ocular surface healing and decrease concomitant inflammation.