Hair loss around the nose?

Hello. I don't know if this is already a thread but I would like some help/suggestions for my 5 year old dog. His name is Coco and a couple of weeks ago we found this blading spot (kind of?) surrounding his nose. (Images attached). It is not lumpy, it is not itchy and Coco doesn't seem to find it bothersome. Coco is not exactly healthy as he had once been paralyzed when he was younger. Context: He suddenly yelped in pain and couldn't walk for a couple of months. We took him to the vet but we couldn't afford the MRI scan so did out best to help him. The vet suggested it might be an infection around his spine since his lower half was unable to move. We fed him steroids and other medicines prescribed by the vet to allow him to walk and run again and now he has recovered and can run walk and jump as much as he wants. (Just not as fast or high anymore). We don't know if the nose hair loss is a delayed side effect of his previous paralysis since it's been 2 years. He didn't show any other symptoms or signs of sickness. After being paralyzed and recovering his stomach has grown weak. So he'll often have stomach aches and barf but it's generally due to eating our food than his food because he doesn't seem to enjoy his kibble too much. His fur also develops slowly but recently the growth rate has increased. We don't know how serious this could be and would like some help from people who have similar experience with their dog or someone who could provide us with help regarding this issue. We want our pup to be as healthy as possible. Please and thank you.