In 1946, famed director John Huston (The Maltese Falcon) made a 58-minute documentary about PTSD (still called "shell-shock" at the time) called Let There Be Light. The film was quickly censored and hidden away. It didn't even get its first public viewing until 1980, by which time the remaining prints had seriously deteriorated. It's now been restored by the National Film Preservation Foundation and posted online, where it can be viewed or downloaded. The Foundation has also posted extensive notes on the film, discussing its history, production, and restoration.
Check it out:
National Film Preservation Foundation: Let There Be Light (1946)