How does Lean Six Sigma method improve healthcare practice in nuclear medicine departments? A successful case of dedicated software applications in oncological PET/CT.

Objectives: Nuclear medicine practice faces challenges concerning radiological risks, image quality variations, management difficulties and costly operations.^1,2,3 This study aimed to apply the Lean Six Sigma (LSS)⁴ method for process standardization, waste reduction and image quality consistency^1,5,6,7 by using nuclear medicine specific tools. Methods The LSS method was used to analyze, monitor and optimize processes in a nuclear medicine department by using the dedicated nuclear medicine software Nuclearis to manage processes. Due to the short half-life of the radiopharmaceutical ¹⁸F-FDG used in oncological PET/CT examinations, we selected this procedure to evaluate the LSS method because most relevant results could be faster accomplished (Lean thinking). The study was divided in three consecutive improvement phases: 1) implementation of protocols from guidelines (n = 134); 2) optimization of PET/CT protocols (1) (n = 339); 3) standardization of the delay between injection time and image acquisition time (uptake time) (n = 67). The radiopharmaceutical dosage, the variation in uptake time and the noise level in the liver region of PET images were used as metrics in our analysis. Results After phase 2 implementation, average image noise levels within patient sub-groups improved from 15% to 12% with no significant change in radiopharmaceutical dosage (from 3.44 ±0.58 MBq/kg to 3.29 ± 0.78 MBq/kg; p = 0,1672), but unacceptable image noise (higher than 15%) was identified in 15% of patients from the phase 2 sub-group (n=339). Data analysis of subjects with unacceptable image noise (n = 51), demonstrated these subjects had process pitfalls concerning higher uptake times than recommended or other operator related bias. After phase 3 implementation, the average noise level was preserved and all subjects of sub-group 3 (n=67) had acceptable image noise with significant decrease in radiopharmaceutical dosage (from 3.29 ± 0.78 MBq/kg to 2.59 ± 0.37 MBq/kg; p < 0.0001). Conclusion The application of LSS⁴ method demonstrated to continuously improve processes in a nuclear medicine environment while strategic data registration, monitoring and assessment are achievable by using specific nuclear medicine information systems. The rational usage of resources and process optimization allow to reduce waste and improve quality in nuclear medicine departments^1,3,6,7.