Comparison of quantitative and qualitative DaTscan results

Objectives: Since our facility started performing DaTscan procedures in December 2017, Siemens Esoft workstations have been utilized to visually read the images. Recent implementation of MIM Neuro DaTscan software allows for quantitative functional evaluation. Computer automated regions of interest are drawn around the right and left putamen areas to yield a Z-score. The Z-score defines the number of standard deviations that a patient is from the mean when compared to a normal age-matched population in the MIM software database, which consists of 209 patients with a mean age of 61 +/- 11 years. The purpose of this study is to determine if the quantitative results from the MIM software correlate with our physicians’ visual evaluations.

Methods: Twenty patients, 12 males and 8 females with a mean age of 65 +/- 11 years, underwent a DaTscan procedure within the Marshfield Clinic Health System. Patient images were presented to two nuclear medicine physicians for a blind read and scored using a scale of normal, mildly abnormal, moderately abnormal, or significantly abnormal. In addition to the visual read, MIM software was utilized for each DaTscan to automatically identify the right and left putamen areas and provide a Z-score based on MIM’s normal age-matched patient database. The highest Z-score obtained between the two areas for each patient was categorized using the following scale: 1.65 = normal, 1.65 to 2 = mildly abnormal, 2 to 2.5 = moderately abnormal, and 2.5 or more = significantly abnormal. The visual grading between the two nuclear medicine physicians and the Z-scores obtained from the MIM software were compared.

Results: Of the twenty patients evaluated, 75% of the patients had the same results for both the quantitative and qualitative DaTscan evaluations. Both physicians and the MIM software did not correlate in 20% of the patients, while 5% had one physician and the MIM disagreeing.

Conclusions: It was determined that the quantitative results from the MIM software, when compared to the normal age-matched population in its database, correlated well with the qualitative visual evaluation performed by the physician. In fact, the MIM software is routinely utilized for reading DaTscan images as it has increased our physicians’ confidence levels.