1. A system comprising: an ablation catheter comprising: an ablation mechanism to ablate a region of interest (ROI) in a material; and an optical coherence tomography (OCT) device to acquire an OCT signal from the ablated ROI; and a computer apparatus coupled to the OCT device to determine a development stage of a lesion formed in the ablated ROI by analyzing an optical property of the ROI as recorded in the OCT signal.