Notfallkeratoplastik mit porcinen Xenotransplantaten bei nekrotisierender Keratitis

Abstract

The great shortage of donor material in Ukraine makes it necessary to find additional sources of transplant material. A possible suitable material are the porcine corneas, as they are similar in structure and biomechanical parameters to the human cornea. The purpose of our study was to analyze the results of therapeutic keratoplasty (KP) with keratoxenotransplants from cryolyophilized porcine corneas in patients with severe necrotizing keratitis. A retrospective analysis of 32 xenotransplantations patients with severe necrotizing keratitis (17 lamellar, 6 stepped perforating, 4 perforating, 5 "biological coverage" according to Puchkovskaya) was completed. All eyes could be preserved, but the graft was rejected in all eyes. A semitransparent xenograft (XG) was achieved in 9 patients (33.3%). The best results were obtained after lamellar XKP with an XT diameter of 3.5 - 6.5 mm. Lamellar XTs with larger diameters (7.0 - 10.0 mm) were opaque. Postoperatively, the intensity of the inflammatory response after stepped XKP was slightly lower than that of the classical perforating XKP. A new KP with human corneas had to be performed in 5 patients, in one case combined with an antiglaucomatous operation and in another case with cataract extraction. Antiglaucomatous surgery had to be performed in 5 patients (15.6%). In the absence of human donor corneas, a porcine keratoxenoimplant can be used as temporary therapeutic keratoplasty in case of emergency stop the inflammation process and to save the eye. In cases of keratoxenoimplant, a poor visual outcome is expected.

Corneal xenotransplantation: Where are we standing?

“…Although not registered as a clinical trial, two DPC clinical studies have also been reported in Ukraine ( Drozhzhyna et al, 2017 ; Turchyn et al, 2019 ). The authors used the same lyophilized cornea manufactured in Ukraine.…”

“…The authors used the same lyophilized cornea manufactured in Ukraine. In one study, DPC was transplanted in 32 eyes with necrotizing keratitis but all the grafts were rejected ( Drozhzhyna et al, 2017 ). In the other study, DPC was transplanted in 49 eyes with complicated corneal ulcers ( Turchyn et al, 2019 ).…”

“…In Zhang's study, hypertonic treated DPC were used in fungal keratitis with variable size, and no patient experienced perforation ( Zhang et al, 2015 ). Conversely, Drozhzhyna et al included perforating, autoimmune or rosacea cornea, and used cryolyophilized DPC with different graft sizes, and thereby reported opaque grafts, of which diameter is 7–10 mm ( Drozhzhyna et al, 2017 ). Larger size of DPC or combined autoimmune disase may lead to a poorer outcome.…”

The Main Aspects of Corneal Transplantation in Ukraine and in the World: Demand Analysis, Keratoplasty Types and Future Development

“…З тектонічною метоюпри обмежених (до 6,5 мм) центральних, парацентральних і периферичних виразках рогівки (пошарова КП, при перфораціїпошарово-наскрізна або наскрізна). З метою збереження окапри значних ураженнях рогівки з перфорацією, що супроводжується лізисом тканини (наскрізна КП, біологічне покриття за Пучківською Н. О. або їх комбінація) [18,19].…”

Anatomic Studies of the Miniature Swine Cornea

“…Swine are increasingly being used in ophthalmology and vision science research to model various ocular diseases (Stricker-Krongrad et al, 2016), develop surgical techniques (Tasaka et al, 2013; Ibarz et al, 2016; McQuaid et al, 2016; Nanavaty and Kubrak-Kisza, 2017; Speri et al, 2017; Tandogan et al, 2016), novel therapies and intervention strategies (Umazume et al ., 2013; Scott et al, 2015; Wang et al, 2016; Lin et al, 2017; Drozhz- hyna et al, 2017; Cong et al, 2018) to prevent vision loss in humans due to similar ocular anatomy and physiology (Beauchemin, 1974; De Schaepdrijver et al, 1992; Gerke et al, 1995; Bartholomew et al, 1997; Ninomiya and Inomata, 2006; Acosta et al ., 2009; Sanchez et al ., 2011). Although studies (Bartholomew et al, 1997; Faber et al, 2008; Jay et al, 2008) have examined anatomical features of the domestic swine cornea, none have compiled a characterization of miniature corneal morphology at both the light and electron microscopic level.…”