Excisional keratectomy combined with focal cryotherapy and amniotic membrane inlay for recalcitrant filamentary fungal keratitis: A retrospective comparative clinical data analysis

Abstract

The aim of the present study was to investigate the efficacy of a novel surgical intervention, excisional keratectomy combined with focal cryotherapy and amniotic membrane inlay (EKCAI), for the treatment of recalcitrant filamentary fungal keratitis. A retrospective analysis was performed of patients who underwent excisional keratectomy combined with conjunctival flap inlay (EKCFI), EKCAI or therapeutic penetrating keratoplasty (TPK) from January 2006 to January 2011. Recalcitrance was determined as being unresponsive to standard medical antifungal therapy for at ≥1 week. Outcome measures among the three intervention modalities were compared. A total of 128 patients had a follow-up of ≥1 year after the primary intervention. The success rates of interventions at 1-year follow-up were 58.33% in the EKCFI group, 88.37% in the EKCAI group and 93.44% in the TPK group (P<0.0002). The preoperative visual acuity of the three groups were similar (P=0.6458), while the postoperative best-corrected visual acuity (BCVA) of patients without recurrence was significantly different among the three groups 3 months after surgery. The best postoperative BCVA was found in the TPK group, while the worst was in the EKCFI group. In conclusion, EKCAI does not require donor cornea, is straightforward surgically, and has a favorable success rate compared with EKCFI.

Comparison of Safety and Efficacy of Intrastromal Injections of Voriconazole, Amphotericin B and Natamycin in Cases of Recalcitrant Fungal Keratitis: A Randomized Controlled Trial

“…The rate of healing with ISVCZ in our study (95%) corresponded with that of multiple previous studies reporting success rates of 66.6 to 100% with the same agent in recalcitrant fungal keratitis. 4 , 5 , 17 , 18 , 19 However, this was in contrast to a recent study by Narayana et al, who demonstrated no added advantage of ISVCZ in the management of moderate to severe fungal corneal ulcers. 20 We believe these conflicting results could be explained by the ethnic variability and regional differences in microbiological profile in both studies.…”

“…Various other interventions, such as penetrating keratoplasty (PKP), collagen crosslinking with photoactivated riboflavin (PACK-CXL), excisional keratectomy combined with focal cryotherapy and amniotic membrane inlay, have been proposed to deal with these cases. [2][3][4] However, these have their own limitations and targeted delivery of antifungal agents at the ulcer site by means of intrastromal injections remains an effective alternative of bypassing these complex options. 5,6 These injections are known to enhance the drug levels at the desired site of the cornea thereby allowing successful healing of the corneal ulcer.…”

Liquid nitrogen cryotherapy for chronic recalcitrant interdigital candidiasis of toe spaces–an uncontrolled pilot study

“…Thermotherapy has been used to treat deep fungal infections, namely, sporotrichosis, chromomycosis, and even candidal keratitis. [3][4][5] Cryotherapy in CI has not been reported in PubMed in English language. The exact mechanism of cryotherapy for treatment of CI is unclear.…”

“…It may be speculated that on rapid cooling, formation of intracellular ice crystals induces dehydration and pH changes, disrupting the infected cells along with Candida spp. 4,5 Slow thawing leads to prolonged exposure to toxic substrates during recrystallization, which increases cell damage. Cryotherapy may also cause denaturation of fungal cell wall proteins.…”

“…Freezing may also remove antigen-antibody complexes. 4,5 Crust formation following the procedure as a result of local ischemia may help to clear chronic infective tissue. 4,5 The limitations in our study include small sample size, no blinding or randomization, and no identification of subtypes of Candida spp., which could not be performed on account of lack of resources.…”