Instructions: Given an abstract, indicate which of the provided candidate titles (Option1 and Option2) best describes it (respond with the text of the title, not option1/2).
Input: Abstract: Surgical experience with grafts of human dura mater sterilized by gamma rays and preserved in alcohol is reported in 804 cases. The method of graft preparation is a simple, cheap, and practical technique for making available a plentiful quantity of large and small pieces of dura to use for plastic reconstruction in everyday neurosurgical practice. Annual inspection for sterility and immunogenicity over an 18-year period indicates that this system of preservation is valid for an unlimited period of time.
Which is the apt title for the abstract? option1: Neurosurgical use of human dura mater sterilized by gamma rays and stored in alcohol: long-term results. option2: Parenteral estrogens for pregnancy prophylaxis [letter]
Output:
Neurosurgical use of human dura mater sterilized by gamma rays and stored in alcohol: long-term results.