We sought to evaluate the ability of fine-needle aspiration (FNA) mapping to find sperm and to guide sperm retrieval after failed microdissection testicular sperm extraction (micro-TESE) in nonobstructive azoospermic men.In this study of consecutive male infertility cases,interventions included testicular FNA mapping and subsequent sperm retrieval.Outcomes included the frequency and location of found sperm on FNA maps after failed micro-TESE and the salvage sperm retrieval success.Among 548 patients undergoing FNA mapping from 2010 to 2016,82 men with previous micro-TESE procedures were identified.The mean time between micro-TESE and FNA mapping was 2.2 years.A total of 2825 (1424 on right and 1401 on left) sites were mapped.At least one site revealed mature sperm in 24 (29.3％) of 82 men with prior failed micro-TESE procedures.There was an equal likelihood of detecting sperm in either testis (6.1％ right;5.7％ left;P =0.58).Digital “heat maps” revealed differences in sperm findings within the testis with mature sperm more likely found in the testis periphery rather than centrally.Fifteen (62.5％) patients subsequently underwent sperm retrieval procedures guided by FNA maps.Sufficient sperm were retrieved in all cases,and in 10 (66.7％) of 15 cases,extra sperm were frozen for future use.In a significant proportion of failed micro-TESE procedures representing the largest study to date,sperm were detected by FNA mapping and could be reliably retrieved through FNA map-guided surgical sperm retrieval.When present,sperm were more likely to be found in the testis periphery rather than centrally with FNA mapping.