Persistence needs a timeline
Persistent headache, dizziness, cognitive difficulty, sleep change, or emotional symptoms should be documented with dates, functional impact, and follow-up. The record should distinguish what was present before the injury from what changed after it.
Functional does not mean unreal
Research reviews describe persistent complaints despite absent structural findings on conventional neuroimaging and discuss brain dysfunction as a possible contributor. That literature does not make a single scan or symptom list a stand-alone diagnosis.
ICD-10-CM includes F07.81, postconcussional syndrome. Coding is a clinical and billing decision, not a promise about a claim.