OBJECTIVE The purpose of this study was to characterize the performance of the Neuroradiology Second Opinion Consultation Service (NSOCS) at our institution to establish the rate, causes, and implications of requests for repeat imaging. MATERIALS AND METHODS We queried 11,753 complete reports of all NSOCS studies for calendar year 2010 for the words "repeat" and "follow-up." We categorized study limitations described in these reports into poor image quality, missing or inadequate MR sequences or CT reformats, lack of IV contrast administration where otherwise deemed appropriate, an "other" category for miscellaneous items, and a "clarification" category for indeterminate findings or recommendations for more advanced protocols. The corresponding available electronic medical records were reviewed. An estimated financial analysis of the NSOCS was additionally performed. RESULTS Repeat imaging studies were recommended in 1.5% of cases. In 0.3% of all cases, a subsequent repeat examination was documented in the electronic medical records. Study limitations were most commonly due to poor image quality (77.5%), followed by missing or inadequate MR sequences or CT reformats (20.3%). The additional estimated cost of repeat imaging was calculated at $14,019.34, with an overall per-patient cost of $2.12 for the service. CONCLUSION Reviewing outside studies generates a very low rate of requests for and performance of repeat studies, and is not a major additional health care expense.