Traumatic wound dehiscence after penetrating keratoplasty

Investigation of mechanical strength and structure of corneal graft-host junction

Dehiscence is a common complication of corneal transplant surgery involving separating the graft from the host eye. The present article aims to investigate fundamental insights into the mechanical and structural aspects of the graft-host junction (GHJ) of a graft that survived in a patient for 13 years after penetrating keratoplasty (PK). Additionally, it adopts the sutur retention strength (SRS) test procedure defined in ISO:7198-2016 and aims to provide a comprehensive test protocol to study the biomechanics of the GHJ in extracted PK buttons. A 9 mm corneal button with GHJ was extracted from a 46-year-old patient who underwent PK 13 years back. The strength of the GHJ was quantified using the SRS test. Corresponding control results were obtained from the SRS tests of a corneoscleral button with no history of any refractive procedure. Birefringence, histological, and scanning electron microscopy (SEM) imaging were used to visualize the microstructural details of the GHJ. The strength of the GHJ was observed to be ten times lower than the native cornea. Histopathological features, such as fragmented Bowman's layer, and fibrosis with a clear demarcation line between host and graft tissue, were observed at the GHJ, suggesting a weak bond across the GHJ. The low strength of the GHJ in PK indicates the high susceptibility of the GHJ towards wound dehiscence.

Temporary Kerato-Prosthesis to Resolve Traumatic Loss of a Healed Corneal Button

The aim of this study is to report a rare case of traumatic complete loss of a donor corneal button successfully resolved by a 24-h implantation of a temporary kerato-prosthesis. A healthy 30-year-old man with a history of prior penetrating keratoplasty (PKP) presented with an open globe following accidental contusive trauma with a ball, while he was playing football. At slit-lamp evaluation, complete dehiscence of the wound at the graft-host junction and complete corneal button loss was evident. The patient was immediately taken to the operating room, but a donor cornea was not available; therefore, a vitreo-retinal temporary kerato-prosthesis was implanted to close the eyeball until a new donor cornea was available. In case of complete dehiscence of the donor-host junction after PKP with corneal button loss, it is possible to use a temporary kerato-prosthesis to stabilize the eye and contain the intraocular structures. We recommend the availability of temporary vitreo-retinal kerato-prosthesis in the operating theatres of Corneal Surgical Units.

Traumatic wound dehiscence after penetrating keratoplasty: Clinical features and outcome in 53 cases in Yemen

AIMS:

Penetrating keratoplasty (PKP) carries the risk of developing wound dehiscence, which can lead to vision loss. The main aim of this study is to analyze the management and outcome of surgery for traumatic wound dehiscence occurring in patients who had PKP.

SUBJECTS AND METHODS:

This retrospective study included post-PKP patients who sustained traumatic wound dehiscence at the Cornea Unit in Yemen Magrabi Eye Hospital between 2008 and 2016. Fifty-three eyes with a history of wound dehiscence were treated with primary wound closure. Patient files were reviewed for type and time of injury, distance visual acuity (VA), and outcome.

RESULTS:

Ruptured globe with dehiscence of wound occurred on average 2.4 years (3 months to 13 years) after PKP. The mean age at wound dehiscence was 22.27 years and males accounted for 77.4% (41). All patients were managed with primary closure of the wound. Lensectomy of traumatic or dislocated lens was the most frequent additional surgical procedure (14, 26.4%), followed by anterior vitrectomy (6, 11.3%). In the end, 43 (81.1%) grafts remained clear. In the last follow-up, 34 eyes (64.1%) had best-corrected VA of 20/200 or better and two eyes had no perception of light.

CONCLUSION:

Rupture globe and wound dehiscence occurs after PKP at the graft–host junction. Wound dehiscence is a lifelong risk after PKP and wound weakness persisted for a long period after PKP. Visual outcome and graft survival are generally poor after the injury, and the restoration of a satisfactory visual result is possible if treated early.