1999 Nissan Pathfinder engine damage question

1999 Nissan Pathfinder mileage: 102,350. I brought my wife's Pathfinder into the local Nissan dealership for an oil change yesterday. While returning home, I noticed the oil light flickering and immediately pulled over. The dipstick showed no oil. At that time I had driven 9 miles. I called the dealership and they sent a truck to my location. They added 4 quarts of oil (capacity) and had me follow them back to the dealership to inspect the filter, etc. They gave the truck a clean bill of health (no surprise I suppose), and I drove home without incident. What is the chance that damage was done to the engine in that 9 miles? Is there an inspection that would show damage? What do you suggest I do to follow up?