diff --git a/docs/Pipelines/PET_Surface.md b/docs/Pipelines/PET_Surface.md
index ff07732a4..6c6dada3a 100644
--- a/docs/Pipelines/PET_Surface.md
+++ b/docs/Pipelines/PET_Surface.md
@@ -43,7 +43,7 @@ where:
 - `ACQ_LABEL` is the label given to the PET acquisition, specifying the tracer used (`trc-<acq_label>`).
 - The reference region is used to perform intensity normalization (i.e. dividing each voxel of the image by the average uptake in this region) resulting in a standardized uptake value ratio (SUVR) map.
 It can be `cerebellumPons` or `cerebellumPons2` (used for amyloid tracers) or `pons` or `pons2` (used for FDG).
-- `PVC_PSF_TSV` is the TSV file containing the `psf_x`, `psf_y` and `psf_z` of the PSF for each PET image.
+- `PVC_PSF_TSV` is the TSV file containing the `psf_x`, `psf_y` and `psf_z` of the PSF for each PET image. It is expected to be generated by the user.
 More explanation is given in [PET Introduction](../PET_Introduction) page.
 
 !!! info