No, 'there are' is required in the above sentence.
Also, you are missing a 'the' in the first phrase. 'The extraction of outline' should instead be:
The extraction of the outline
Extracting the outline
It might be a good idea to rewrite the sentence to something like:
Extracting the outline becomes much harder if there are very short
boundary edges where only a few laser points reside.
This avoids using the word 'very' too much.
Just to let you know, the opening sentence could be:
I am having difficulty with constructing the following sentence:
or something similar. As it stands, it's not grammatically correct.