Quantitative evaluation of postembolized splenic tissue using technetium-99m sulfur colloid

Area of Science:

• Nuclear Medicine
• Radiology
• Transplant Surgery

Background:

• Hypersplenism is a condition requiring management, often involving procedures like partial splenic embolization (PSE).
• Accurate assessment of splenic tissue post-PSE is crucial for evaluating treatment efficacy in renal transplant recipients.
• Existing imaging modalities like CT and MRI have limitations in precisely quantifying functional splenic tissue post-embolization.

Purpose of the Study:

• To evaluate the efficacy of Technetium-99m sulfur colloid ((99m)Tc-SC) scintigraphy in quantifying residual splenic tissue.
• To compare the precision of (99m)Tc-SC scans with CT and MRI for assessing post-PSE splenic volume.
• To validate a liver-spleen phantom model for assessing (99m)Tc-SC scan accuracy.

Main Methods:

• Utilized (99m)Tc-SC SPECT/planar imaging to quantify residual splenic tissue in 17 renal transplant patients undergoing PSE.
• Developed and employed a liver-spleen phantom with simulated emboli to validate the accuracy of the imaging technique.
• Analyzed phantom and patient data using computer imaging to estimate embolized splenic volume.

Main Results:

• A high correlation (0.996, P < 0.001) was observed between actual and computer-estimated splenic volume displacement in the phantom.
• (99m)Tc-SC scintigraphy demonstrated superior precision in measuring decreased functioning splenic tissue compared to CT and MRI.
• The technique proved effective in quantifying residual splenic tissue post-PSE in renal transplant patients.

Conclusions:

• (99m)Tc-SC scintigraphy is a highly accurate and precise method for quantifying residual splenic tissue after PSE.
• This nuclear medicine approach offers significant advantages over CT and MRI for assessing post-embolization splenic function.
• The validated phantom model supports the reliability of (99m)Tc-SC scans in clinical applications for hypersplenism management.