[Characteristics of traumatic versus spontaneous wound dehiscence after penetrating keratoplasty].

Background And Purpose: After penetrating keratoplasty (PK) patients remain at risk for wound dehiscence at the graft-host junction even years after surgery. The aim of our study was, firstly, to assess the site-specific characteristics between traumatic and spontaneous wound dehiscence at the graft-host junction and, secondly, to determine the incidence of traumatic and spontaneous wound dehiscence.

Methods: The medical records of all 243 patients who underwent a penetrating keratoplasty from 1 March 1996 to 1 March 2012 were retrospectively reviewed. During a 16-year period 9 eyes showed signs of open wound dehiscence after blunt ocular trauma and 7 eyes spontaneously after suture removal.

Results: Over the 16-year period, the incidence of traumatic wound dehiscence was 3.7 % (9 of patients), whereas the incidence of spontaneous wound dehiscence after suture removal was 2.9 % (7 of 243 patients). In traumatic cases the graft dehiscence occurred in 88.9 % (8 of 9 patients) in the nasal part, predominantly in the inferior nasal part. In one case (11.1 %), only the temporal part was affected. The average extent of wound dehiscence for traumatic cases was 96° of the total wound circumference in the nasal part, and only 30° of the circumference in the temporal part. Spontaneous dehiscence after suture removal mainly occurred at temporal site in 71.4 % (5 of 7 eyes), mostly temporal inferior. Only in one case was the nasal part affected (14.3 %). The average extent of wound dehiscence in spontaneous cases was 54° of the total circumference in the temporal part and 21° in the nasal part. The total average extent of dehiscence was significantly larger in traumatic cases, 126° (one third) for traumatic and 75° (one fifth) of the wound circumference for spontaneous cases. All of the re-sutured grafts retained clarity, except for 3 eyes among the traumatic cases.

Conclusion: The difference between both groups was significant regarding the localisation, the extent and the clarity of the re-sutured grafts. The nasal inferior part was the most affected area in traumatic cases probably as a result of indirect, contrecoup injuries, and the temporal part in spontaneous wound dehiscence probably due to direct minor forces.