## 4 Discussion  
Corneal stromal wound healing is a very complex and orderly process with keratocyte death and repopulation, sequential transformation of keratocytes into fibroblasts and myofibbroblasts, infiltration of limbal and circulating immune cells, and remodeling of the corneal extracellular matrix (ECM) structure [19; 20; 21; 22]. Several properties explain the beneficial effects of AM transplantation for ocular surface reconstruction. Foremost, the AM has a mechanical function resulting in the growth of epithelial cells on the ocular surface. Furthermore, it stimulates epithelialization through the production of the epithelial growth factor (EGF), hepatocyte growth factor (HGF), and keratinocyte growth factor (KGF). Ultimately, the AM reinforces the adhesion of basal epithelial cells and prevents epithelial cell apoptosis. The inhibition of the proliferation of corneal, limbal, and conjunctival fibroblasts results from the suppression of TGFb signaling along with the reduced expression of TGFb-1, b-2, and b-3 isoforms and TGF-beta receptor II, which entails the anti-fibrotic effect of the AM [23]. The anti-inflammatory effect results from the inhibition of the expression of pro-inflammatory cytokines (IL-1a, IL-2, IL-8, IL-10, IFN-c, bFGF, TNFb, and PDGF) from the damaged ocular surface [24]. Additionally, it has been demonstrated that the AM stroma  
Figure 3: Patient number 3, right eye. (**A**) Anterior segment optical coherence tomography (AS-OCT) showing corneal thinning with residual stromal tissue (asterisk), Seidel positive. A reflex saturation beam artifact is visible as a dashed line (arrow). (**B**) The postoperative outcome at week 1. The therapeutic lens is seen above the corneal epithelium as a hyper-reflective band (arrow). The epithelium regrowth is indicated by a small asterisk and delimited by the Bowman’s membrane, visible as a hyper-reflective band (arrow). (**C**) The post-op outcome at 1 month shows a similar corneal appearance to week 1.  
acts as a trap for the inflammatory cells that undergo apoptosis [24]. Moreover, AM stromal and epithelial cells express FAS receptor, driving the fibroblast and inflammatory cells to apoptosis. The lack of immunogenicity avoids the need of any immunosuppressive treatment, enhancing the benefit of AMT. Finally, AM anti-angiogenic and anti-microbial properties have been demonstrated [24]. Current AMT techniques involve suturing the graft or patch of AM over the ocular surface. Nevertheless, the corneal sutures can not only cause postoperative pain and discomfort to patients [25] but also lead to complications such as additional trauma, suture abscesses [26; 27], infections [28; 29], granuloma formation [30], and tissue necrosis [31]. Furthermore, the inflammatory effect of corneal suture [32] can lead to an unsuccessful repairing attempt, especially if the corneal damage is due to an inflammatory disease. For this reason, sutureless techniques have been developed, including the use of cyanoacrylate glue. Although proven effective, this type of glue can cause complications, such as chronic inflammation and delay of wound healing due to its toxicity [33; 34; 35]. Fibrin glue is a preferred option to fix the AM to the ocular surface. The major drawback to its use is the risk of transmitted disease from blood donors [35; 36]. Other SAMT-reported procedures include mounting the amniotic membrane on an ocular conformer [37] or directly on a contact lens [38]. [PERSON] et al. managed to prepare a contact lens-shaped AM using glutaraldehyde and dialdehyde starch as a cross-linking agent [39]. The literature reports the use of a self-retaining cryopreserved amniotic membrane (PROKERA(r) Slim, Bio-Tissue, Miami, FL, USA) for the treatment of dry eye disease [40], corneal ulcers [41], [PERSON] syndrome/toxic epidermal necrolysis [42], and Sjogren's syndrome [43]. Some authors reported the use of a symblepharon ring in order to fix the AM to the ocular surface in patients with chemical injuries or toxic epidermal necrosis/Stevens-Johnsons syndrome [44; 45].