Optimization of attenuation and scatter corrections in sentinel lymph node scintigraphy using SPECT/CT systems

Area of Science:

• Nuclear Medicine
• Medical Imaging
• Oncology

Background:

• Sentinel lymph node (SLN) imaging is crucial for breast cancer staging.
• SPECT/CT systems offer potential for improved SLN detection.
• Optimization of attenuation correction (AC) and scatter correction (SC) in SPECT/CT for SLN imaging requires further investigation.

Purpose of the Study:

• To determine the optimal AC and SC settings for SPECT/CT imaging of SLNs.
• To enhance the detectability of SLNs using SPECT/CT.

Main Methods:

• Fifty-six female breast cancer patients underwent SPECT/CT imaging.
• Four image sets were generated: without AC/SC, with AC only, with SC only, and with both AC and SC.
• Five nuclear medicine physicians assessed image interpretability and SLN detection rates on a 1-5 confidence scale.

Main Results:

• SPECT/CT with AC and without SC (AC+SC-) yielded the highest detection rate (98.2%) and confidence level (4.81 ± 0.38).
• Planar imaging showed a detection rate of 94.6%.
• Scatter correction (SC) negatively impacted SLN detection, with AC+SC+ showing the lowest detection rate (78.6%).

Conclusions:

• Attenuation correction (AC) is beneficial for improving SLN detection in SPECT/CT imaging.
• Scatter correction (SC) should not be applied in SPECT/CT for SLN imaging as it can lead to the disappearance of faint SLNs.
• Optimized AC settings enhance diagnostic accuracy in SLN detection via SPECT/CT.