The success of penetrating keratoplasty for keratoconus

Abstract

We report the results, over a 20 year period up to 1989, of 201 penetrating keratoplasties in 198 eyes of 158 patients. The five year graft survival was 97%. A corrected visual acuity of 6/12 or better was attained by 91%. The mean spherical equivalent refraction on removal of sutures was -2.68 Ds and the mean cylindrical correction was -5.56 Ds. The cumulative time to dispensing final refractive correction was 38 months for 90% of patients. Rejection episodes occurred in 20% of grafts and were associated with loosening of sutures and bilateral grafts. Atopic patients (28%) were not at greater risk from rejection. Graft refractive surgery was undertaken in 18% and, of these, 55% achieved 6/12 vision or better with an refractive correction which could be dispensed and tolerated within 6 months.

Update and review of Urrets-Zavalia syndrome

“…In a retrospective study that analyzed more than 2,000 patients with PK, the incidence of UZS was higher in patients with macular dystrophy than in patients with keratoconus (7) . We believe that patients with ke ratoconus are not at increased risk of UZS, as stated in previous studies (26) . Increased IOP during and immediately after presentation of UZS has been verified in the majority of reported cases; however, the maintenance of ocular hypertension was not clearly demonstrated in these cases (34) .…”

“…Early reports indicated the use of atropine in PK as associated with such complications (1) . Keratoconus was also suggested to be involved in the pathogenesis of UZS as a result of decreased corneal rigidity and enhanced response to mydriatics (3,26) . Intraocular pressure (IOP) elevation, with or without pupillary block, has been implicated as the trigger mechanism of UZS (4,27) .…”

Assessment of endothelial cell density and corneal thickness in corneal grafts an average of 5 years after penetrating keratoplasty

“…Different studies on PKP have reported that the 1-year survival rate of donor cornea is up to 90 %, at 5 years it is 88 %, at 10 years it is 80 % and in the 2007 Australian graft report it is 60 % [10][11][12]. Graft clarity rate can reach the extent of 97 % after 4 years in the low-risk group [13]. In transplanted corneas, endothelium can keep its function in some cases even for 30 years [14][15][16][17], with an initial cell density above 2,500 cells/mm 2 ( Table 2).…”

Traumatic wound dehiscence after penetrating keratoplasty—a cause for concern

“…[7][8][9][10][11][12][13][14] However, this problem has not been adequately highlighted in the UK. 15 In this paper, we report the incidence and outcome of traumatic graft ruptures in a tertiary referral centre in the UK. We have examined the causes of traumatic corneal graft ruptures and the long-term visual outcome in patients with ruptured corneal grafts on prolonged follow-up.…”