Background
We sought to determine whether drinking lemon juice reduces extra-cardiac activity and improves image quality on 99mTc-tetrafosmin myocardial single photon emission computed tomography (SPECT).
Methods
Eighty male patients were enrolled in this study and divided into four groups with 20 patients in each group. Each patient received 259–333 MBq tetrofosmin. Ten minutes after injection no action was taken for group 1 (G1), patients in group 2 (G2) each drank 250 ml of water, patients in group 3 (G3) each drank 250 ml of whole milk, and patients in group 4 (G4) each drank 250 ml diluted lemon juice. Myocardial perfusion imaging without attenuation correction was performed after a 1 day rest–stress protocol. Both rest and stress images were aligned at corresponding slices for comparison. Interfering activity was determined visually on reconstructed images, and the heart-to-liver (H/L) ratios were calculated with planar images at 25–30 min and at 45–50 min.
Results
Interfering activity was seen in 80% of G1, 70% of G2, 60% of G3, and 35% of G4 (G4 vs. G1, P=0.006) on rest images, and in 70% of G1, 60% of G2, 55% of G3, and 30% of G4 (G4 vs. G1, P=0.014) on stress images at 25–30 min. It was also observed in 60% of G1, 50% of G2, 45% of G3, and 15% of G4 (G4 vs. G1, P=0.006) on rest images, and in 50% of G1, 45% of G2, 40% of G3, and 10% of G4 (G4 vs. G1, P=0.011) on stress images at 45–50 min. The mean H/L ratios of rest images were 0.47±0.13 for G1, 0.71±0.17 for G2, 0.65±0.12 for G3, and 0.93±0.23 for G4 at 25–30 min, and 0.63±0.14 for G1, 0.73±0.14 for G2, 0.85±0.25 for G3, and 1.15±0.25 for G4 at 45–50 min. On stress images, they were 0.49±0.11 for G1, 0.74±0.16 for G2, 0.69±0.11 for G3, and 0.98±0.22 for G4 at 25–30 min, and 0.66±0.15 for G1, 0.77±0.11 for G2, 0.89±0.26 for G3, and 1.21±0.19 for G4 at 45–50 min.
Conclusion
Drinking 250 ml of diluted lemon juice accelerates the transit of tetrofosmin through the liver parenchyma and improves image quality on 99mTc-tetrafosmin myocardial SPECT.
