Therapeutic penetrating keratoplasty is a corneal transplant procedure performed to treat non-healing corneal ulcers and corneal ulcers with perforation with an aim to eliminate the infective foci and maintain the integrity of the globe. This complex surgery typically lasts between 30 minutes and 1.5 hours. The type of anesthesia used for therapeutic keratoplasty can vary, ranging from local anesthesia (such as retrobulbar, peribulbar, or sub-tenon anesthesia) to general anesthesia.¹ Some case series have also reported performing penetrating keratoplasty under topical anesthesia with sedation in situations where local and general anesthesia were contraindicated.²

During penetrating keratoplasty, the eye is kept open for a brief period following removal of the diseased host tissue until placement of the donor corneal tissue, which increases the risk of positive vitreous pressure (PVP).  PVP is associated with lens expulsion, posterior capsular rupture, vitreous loss and devastating suprachoroidal expulsive hemorrhage.³

 Poor ophthalmic anesthesia results in incomplete akinesia and inadequate analgesia which are independent risk factors for PVP. This is followed by lack of patient co-operation, intra-operative anxiety and continuation of surgery difficult. Intraoperative anxiety can precipitate systemic complications like pulmonary edema, cardiac crisis or a stroke. In this study, we aim to analyze the efficacy of peribulbar anesthesia in therapeutic penetrating keratoplasty and the ocular risk factors associated with poor anesthesia and its clinical outcomes