 Over the last decade, optical coherence tomography OCT has become a critical component to the evaluation of ophthalmic disease. Similar to ultrasound, OCT uses light to reconstruct an image of the tissue of interest. In effect, OCT has become to function as a light biopsy, allowing clinicians to visualize subtle pathologic changes in the tissue, such as macular edema or subretinal fluid. The use of OCT in the clinic setting has become the standard for monitoring diseases such as macular degeneration and diabetic retinopathy. It has quickly become the most frequent ordered diagnostic test in ophthalmology. 