Use sp_drv_image_setdata which accesses the Transact-SQL function setadata.
sp_drv_image_setdata locator, offset, new_data, datalength
locator – an image_locator that references the image column to insert in.
offset – an integer specifying the position from which to start writing the new content.
new_data – varbinary or image data to insert.
data_length – an integer containing the number of bytes written.
None.
