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Does PACK-CXL Change the Prognosis of Resistant Infectious Keratitis?
Purpose:
To examine the clinical characteristics, treatments, and prognosis of all cases of infectious keratitis resistant to conventional therapy and treated by photo-activated chromophore for keratitis corneal cross-linking (PACK-CXL) in one institution between 2012 and 2016.
Methods:
A database search of patients who underwent PACK-CXL (ultraviolet-A for 10 minutes for irradiance of 9 mW/cm2) for infectious keratitis unresponsive to medical treatment at a tertiary care hospital was conducted. The following parameters were documented: patient demographic information, corrected distance visual acuity (CDVA) before the procedure and at the end of follow-up, characteristics of the ulcer, antibiotic treatment prior to CXL, culture results, and long-term complications. Cases with less than 1 year of follow-up were excluded.
Results:
PACK-CXL was performed in 18 consecutive eyes. CDVA at the time of presentation was 1.47 logMAR (mean 1.47 ± 0.72 logMAR, range: 0.00 to 2.79 logMAR). Culture results were positive in 72% of eyes (13 of 18 patients) and no pathogens were identified in 28% of eyes (5 of 18 patients). All patients were treated with more than one antibiotic. The mean CDVA at the end of follow-up was 1.22 logMAR (mean: 1.22 ± 0.89 logMAR, range: 0 to 2.07 logMAR). There was no significant change between CDVA at presentation to CDVA at the end of follow-up (matched pair, P = .126). One eye underwent an emergency therapeutic penetrating keratoplasty.
Conclusions:
Patients with large, central corneal ulcer and poor CDVA who were resistant to conventional treatment underwent PACK-CXL. At the end of follow-up, only one eye required emergency penetrating keratoplasty. This low rate might be attributed to a good response to CXL. [J Refract Surg. 2018;34(8):559-563.].
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