Can a precise nerve block stop shingles pain before it becomes chronic?

This trial compares two ultrasound-guided nerve blocks — the midpoint transverse process to pleura (MTP) block and the erector spinae plane (ESP) block — for treating acute pain from shingles (herpes zoster) on the chest. About 90 adults with moderate to severe pain will receive one of the two blocks, which combine a numbing medication (bupivacaine) with an anti-inflammatory steroid (methylprednisolone). The goal is to see which block provides better pain relief and whether it can prevent postherpetic neuralgia, a chronic pain condition that can linger after the rash heals.