Local anaesthesia as a standard of care for penetrating keratoplasty?

BACKGROUND/OBJECTIVES: To determine preferences in the use of local anaesthesia (LA) versus general anaesthesia (GA) for penetrating keratoplasty (PK), and to examine the safety of LA for PK. SUBJECTS/METHODS: A retrospective analysis of PKs performed at an ophthalmology department in Canada from 01/01/2008 to 01/01/2020 was conducted to investigate rate of major complications. A questionnaire was also sent out to cornea specialists in the United Kingdom (UK) and Canada to determine trends in anaesthesia use for PK. Data on anaesthesia use in keratoplasty data was also obtained from the National Health Service Blood and Tissue (NHSBT) register. RESULTS: The retrospective study found that 2143 PKs were performed under LA by 4 surgeons. The following complications were revealed: 1 acute anxiety attack with tachycardia, 3 extraocular myotoxicity cases requiring squint surgery, 1 expulsive suprachoroidal haemorrhage and 1 retrobulbar haemorrhage. The survey revealed 92% of cornea specialists in Canada preferred LA to GA. In the UK, 4.5% of specialists preferred LA, with most preferring GA due to suprachoroidal haemorrhage risk. NHSBT data revealed that 86.6% of 6181 PKs performed in UK between 01/04/2015 and 31/03/2020 were done under GA. CONCLUSIONS: LA is preferred for PK in Canada, in contrast to the UK where GA is preferred. Our retrospective study suggests a low incidence of LA-related complications. We suggest that LA should be considered for most cornea transplant techniques, including optical penetrating keratoplasty. Rising worldwide keratoplasty numbers, ageing populations and risks of pandemics (e.g. COVID-19) give more reason for reduced reliance on GA.

Oral Miltefosine as Adjunctive Treatment for Recalcitrant Acanthamoeba Keratitis.

PURPOSE: Acanthamoeba keratitis is a rare, vision-threatening disease. Commercially available antiamoebics are poorly cysticidal and highly toxic, and therapeutic keratoplasties can be complicated by recurrence or graft failure. We aimed to discuss the use of oral miltefosine for treatment of recalcitrant Acanthamoeba keratitis. METHODS: A 44-year-old contact lens wearer presented with a 2-week history of red painful eye and decreasing vision. After poorly responding to topical corticosteroid on the presumptive diagnosis of anterior uveitis, she developed radial keratoneuritis. Corneal scraping was positive for Acanthamoeba. No clinical response to treatment was observed with topical chlorhexidine 0.02%, polyhexamethylene biguanide 0.02%, and oral voriconazole. She then underwent 2 therapeutic keratoplasties with prompt recurrence of the disease in the keratoplasty graft. RESULTS: Oral miltefosine was added to the treatment. She underwent a third penetrating keratoplasty 8 months later. The excised button was negative for amoeba. She continued miltefosine for 3 more months. No recurrence was observed after 30 months. CONCLUSIONS: This case shows resolution of recalcitrant Acanthamoeba keratitis with oral miltefosine in an immunocompetent patient. Further clinical evidence would be needed to possibly incorporate this medication in the antiamoebic armamentarium.