BACKGROUND: Infectious keratitis is a major cause of global blindness. We tested whether standalone photoactivated chromophore corneal cross-linking (PACK-CXL) may be an effective first-line treatment in early to moderate infectious keratitis, compared with standard antimicrobial treatment.
METHODS: This is a randomized, controlled, multinational phase 3 clinical trial. Participants in five centers in Egypt, India, Iran, Israel, and China, aged ≥ 18 years, with infectious keratitis of presumed bacterial, fungal, or mixed origin, were randomly assigned (1:1) to PACK-CXL, or antimicrobial therapy. Outcomes measures included healing, defined as time to re-epithelialization of the corneal epithelial defect in the absence of inflammatory activity in the anterior chamber and clearance of stromal infiltrates. Treatment success was defined as the complete resolution of signs of infection.
RESULTS: Between July 21, 2016, and March 4, 2020, participants were randomly assigned to receive PACK-CXL (n = 18) or antimicrobial therapy per American Academy of Ophthalmology (AAO) guidelines (n = 21). No participants were lost to follow-up. Four eyes were excluded from the epithelialization time analysis due to treatment failure: two in the antimicrobial therapy group, and two in the PACK-CXL group. Success rates were 88.9% (16/18 patients) in the PACK-CXL group and 90.5% (19/21 patients) in the medication group. There was no significant difference in time to complete corneal re-epithelialization (P = 0.828) between both treatment groups.
CONCLUSIONS: PACK-CXL may be an alternative to antimicrobial drugs for first-line and standalone treatment of early to moderate infectious keratitis of bacterial or fungal origin. Trial registration This trial is registered at ClinicalTrials.gov, trial registration number: NCT02717871.

Corneal melt, an ophthalmological condition in which corneal epithelium is lost accompanied by thinning of the corneal stroma, can lead to corneal perforation and cause loss of vision. Corneal melt is the most serious side effect of topical nonsteroidal anti-inflammatory drugs (NSAIDs), one of the topical treatments of ocular inflammation. NSAID-induced corneal melt (NICM), initially doubted, is real, having been reported by multiple groups. NICM is induced by all but one of the approved ocular NSAIDs and occurs usually in patients whose cornea is compromised by ocular surgery, diabetes, or autoimmune diseases. Its true incidence, most likely low, remains unknown. NSAID dose and duration of treatment may be important for NICM. NICM appears to evolve in two stages: the epithelial stage-marked by a corneal epithelial defect, reduced eicosanoid levels, leukocyte infiltration, and matrix metalloproteinase-facilitated desquamation-and the stromal stage, characterized by degradation of stromal collagen by activated matrix metalloproteinases. Awareness of this ominous side effect, its risk factors, and the need for prompt action once diagnosed, including NSAID discontinuation, will help mitigate the risk of NICM. Further understanding of NICM and development of efficacious treatments or safer alternatives should help eliminate this rare, but severe, side effect of ocular NSAIDs.

BACKGROUND: The ocular presentation of Castleman\'s disease (CD)-associated paraneoplastic pemphigus (PNP) has rarely been reported. In this report, we describe a young patient with CD-associated PNP who had recurrent corneal ulceration in addition to cicatrizing conjunctivitis.
METHODS: We describe a case of 23-year-old male with mucocutaneous erosion and conjunctival injection and erosion who was found to have PNP. Pelvic hyaline-vascular CD was detected and completely excised. The mucocutaneous lesions improved postoperatively. Two years after pelvic surgery, the patient gradually developed conjunctival symblepharon in both eyes and pterygium in the right eye. The patient then underwent a successful exclusion of the symblepharon, an excision of the pterygium and an amniotic membrane transplantation in the right eye. However, after 6 months, he experienced an aseptic corneal ulcer and recurrent pterygiumin the right eye. After treatment with systemic and local immunosuppressive medications, the corneal ulcer gradually healed and remained stable.
CONCLUSIONS: Corneal ulceration and melting, in addition to conjunctivitis, as a complication of CD-associated PNP, can be successfully managed with systemic and local immunosuppressants.

Collagen cross-linking (CXL) with ultraviolet light-activated riboflavin is a corneal surface procedure developed for the treatment of keratoconus and corneal ectasia. With the known microbicidal and corneal stiffening effects of ultraviolet irradiation and photoactivated riboflavin, it has recently been introduced for the management of infectious keratitis, especially for ulcers resistant to antimicrobial therapy or associated with corneal melting. Various authors have attempted to use CXL as an adjunctive, salvage or even as the sole treatment for infectious corneal ulcers. The aim of this review was to provide a summary of the clinical studies in the literature. It is worth noting that there is still no consensus on the treatment protocol of CXL against infectious keratitis. The disparities in outcome measures, treatment protocol and study design can confound the interpretation and hamper the generalization of the study results. Based on current evidence, the role of CXL in infectious keratitis remained unclear despite the reported success in some clinical cases. Further investigations are warranted concerning the efficacy and safety of treating infectious keratitis with CXL.

OBJECTIVE: To evaluate the effect of Collagen cross-linking on the prevention of melting in rabbit corneas after alkali burn.
METHODS: Twenty New Zealand white rabbits were randomly divided into model control group and collagen cross-linking treatment group. The second group of rabbits received collagen cross linked treatment. Both groups were applied with antibiotic eye drops to prevent infection. The corneas were evaluated for melting, opacity, pathological and immunohistochemistry, record the changes when 28 days after the animals were killed.
RESULTS: In the control group, 6 out of 8 rabbits showed corneal melting after injury (14±4) days, while two corneal perforated. In collagen cross-linking treatment group, one rabbit showed corneal melting after injury 23 days, without corneal perforation; corneal dissolution rate between the two groups was significantly different (P <0.05). Pathological examination suggested that in the treatment group, mild corneal edema, mild damage to collagen fibers, inflammatory cell infiltration was significantly less than the control group. Immunohistochemistry showed that corneal collagen fibers arranged in neat rows in the control group.
CONCLUSIONS: Collagen cross-linking treatment not only can prevent and delay the corneal melting after alkali burn, but also can reduce the destruction of corneal collagen fibers and infiltration of inflammatory cells in the corneal tissue.