Comparison of R-Rated DVD and German Video (presumably unrated)
Runtime R-Rated: 01:38:52 NTSC
Runtime Unrated: 01:34:37 PAL
The R-Rated version features in one sequence some alternate, slightly more harmless shots than the unrated version.
Whether the German Video is in fact an unrated version of the movie is not completely sure, but the typical "R-Rated/Unrated-like" alternate material suggests that.
The runtime indications refer to the R-Rated version.
2 alternate shots = No time difference

0:00:00 - 00:00:21
The unrated version misses out the "Tri Star"-logo.
21 sec.

01:10:35 - 01:10:37
R-Rated:
Some shots of the squirming psychiatrist were replaced by more harmless shots of the screaming Helen.

Unrated:

No time difference

01:10:37 - 01:10:39
R-Rated:
The psychiatrist screams and jumps up and down during his death until he finally dies.

Unrated:
From the reverse angle one sees the screaming Helen in the wheelchair and the psychiatrist being murdered in the meantime.

No time difference

01:38:45 - 01:38:52
The unrated version again misses out the "Tri Star"-logo after the end credits.
17 sec.