Yes, perlite can be added in a limited way.Go to the hardware store, buy a 1/4" aluminum rod. You can aerate your soil with this. Don't go nuts perforating the soil. But, 2-3 after each watering will have a similar effect as having more perlite in the soil. It will help get air into the soil. You can give the rod a little sideways shove to dislodge the soil, which will loose it a little. Don't shove it far. Just a little tweak can loosen the soil more than just the single shaft alone. And, you can dribble some perlite down those holes to maintain that airway. You can crush the perlite to be smaller and go down the shaft better. (It's a little tedious. But, it can be done.).
Hint: Put the rod in a drill chuck and spin one end against a steel file to create a rounded/tapered point. This will minimize damage to root. Then bend the oppsite end 90 degrees to make a 4" handle. I bought a 36" rod, cut it 18", and made two that are 14" long.
I got the idea to do this using a Control Wizard Accurate 8 soil pH probe. I noticed the plants seemed to like it, especially in flower. It's 3/8" diameter. Much more displacement. I think the plants like that better than the narrower rod I use. But... with a young plant, I'd be conservative. A 3/8" rod would definitely let you get perlite shafts into the soil. But, with a young plant, maybe the 1/4" would be better. (I've probed my young plants using my pH probe, without problems. I doubt it would be a problem. But, you should be able to get some fine perlite down a 1/4" hole.