Per-rectal Portal Scintigraphy with Technetium-99m Pertechnetate for Esophageal Varices

Per-rectal portal scintigraphy is a non-invasive method in which a radioisotope is used for imaging of the portal collaterals. Per-rectal portal scintigraphy with 99m-technetium pertechnetate (99mTcO4-) was performed in 42 subjects to evaluate the portal hemodynamics. Ten healthy controls, 13 cases of liver cirrhosis without esophageal varices, 15 cases of liver cirrhosis with esophageal varices, and 4 cases of portal systemic shunt were included in this study. Moreover, in 4 patients who underwent transabdominal esophageal transection, per-rectal portal scintigraphy was repeated one month postoperatively. Portosystemic shunt index was calculated by the following equation. Shunt Index (%) = (99mTcO4 Counts of Heart/99mTcO4 Counts of Liver and Heart) × 100. The results, expressed as shunt index (SI) were: 8.8 ± 5.2 in controls, 21.2 ± 8.0 in cirrhotic patients without esophageal varices, 31.0 ± 18.5 in cirrhotic patients with esophageal varices, and 49.0 ± 6.9 in patients with portosystemic shunt. After transabdominal esophageal transection, the shunt indices were decreased in all four cases. Morphological improvements of the esophageal varices were also observed. These results suggest that the shunt index measured by perrectal portal scintigraphy may be useful for assessment of portal collaterals, especially for patients with esophageal varices.