Timing of multiple PICL procedures

My 19-year-old son had his first ePICL procedure 11 weeks ago. At that time, we scheduled a second procedure for four months later, as we were concerned that Dr. C’s availability might become limited.

So far, he has not experienced any noticeable improvement. Based on what I’ve read, some patients don’t see results until 4–6 months after the procedure, which means we may proceed with the second treatment before knowing whether the first was effective.

We are committed to trying at least two PICL procedures before deciding whether this approach is appropriate for his specific injuries. I’ve come across accounts of patients who saw little or no improvement after the first procedure but experienced more meaningful progress after the second. However, I’ve also read that some patients prefer spacing procedures 6–9 months apart.

My son returned to baseline relatively quickly after the first procedure, and his flares have been minimal. We opted for a shorter interval between treatments because his condition is significantly impacting his ability to function and attend college, and we are eager to help him regain that capacity.

My question is about timing and efficacy: is there any reduction in effectiveness when procedures are performed closer together? Are there other factors we should consider when deciding on the timing of the second procedure?