The transparency of cornea plays an important role in vision and if it gets compromised leads to blindness. Corneal transparency is a vital predictor for its function. Recently corneal blindness has become a topic of global interest. Keratoplasty is the only procedure to restore vision in corneal blindness. With the advent of component or lamellar keratoplasty(LK), penetrating keratoplasty(PK) has lost its charm but still, there are so many indications prevailing around for this procedure. Complications like graft rejection, infection, graft failure, and post keratoplasty glaucoma are more in PK as compared to LK. To monitor all these complications high-resolution multiplanar imaging modality is the need of an hour. The Anterior Segment Optical Coherence Tomography can be of potential usefulness in evaluating the cornea at various tissue planes after PK. In this book author has tried to touch all the aspects of the usefulness of Anterior Segment Optical Coherence Tomography in penetrating keratoplasty. This book will be helpful for all the ophthalmologists especially cornea surgeons in managing the patients after PK.