Because the celiac is one of the arteries supplying the intestines, any interrruption of the blood supply means the intestines cannot digest as well, and there will be weight loss. There are several ways to approach a blocked artery. Sometimes medication to thin the bood is used to prevent clots. However, with 90% blockage, you may be more likely to have an intervention to open the artery such as angioplasty and a stent. With angioplasty a tiny balloon catheter is threaded through the arterial system. When it reaches the area of the blockage, the balloon is inflated, pushing the clogging material to the walls of the artery. A stent is then placed to keep the artery open once the catheter is withdrawn. Another possibility is an endartectomy in which the plaque is scraped from the walls of the artery. A third possibility is that a portion of the celiac artery may be removed and replaced with a graft from another part of your body. I'm confident your doctors will be discussing the viable options with you shortly.