Role of per-rectal portal scintigraphy in long-term follow-up of congenital portosystemic shunt

Abstract

Background: Congenital portosystemic shunt (CPSS) has the potential to cause hepatic encephalopathy and thus needs long-term follow-up, but an effective follow-up method has not yet been established. We aimed to evaluate the importance of per-rectal portal scintigraphy (PRPS) for long-term follow-up of CPSS. Methods: We retrospectively examined shunt severity time course in patients (median: 9.6 y, range: 5.2-16.6 y) with intrahepatic (n = 3) or extrahepatic (n = 3) CPSS by using blood tests, ultrasonography or computed tomography, and PRPS. Per-rectal portal shunt index (cutoff: 10%) was calculated by PRPS. results: PRPS demonstrated that the initial shunt index was reduced in all intrahepatic cases (from 39.7 ± 9.8% (mean ± SD) to 14.6 ± 4.7%) and all extrahepatic cases (from 46.2 ± 10.9 to 27.5 ± 12.6%) during the follow-up period. However, ultrasonography and computed tomography disclosed different shunt diameter time courses between intrahepatic and extrahepatic CPSSs. Initial shunt diameter (5.8 ± 3.5 mm) reduced to 2.0 ± 0.3 mm in intrahepatic cases, but the initial diameter (6.3 ± 0.7 mm) increased to 10.6 ± 1.0 mm in extrahepatic cases. All patients had elevated serum total bile acid or ammonia levels at initial screening, but these blood parameters were insufficient to assess shunt severity because the values fluctuate. conclusion: PRPS can track changes in the shunt severity of CPSS and is more reliable than ultrasonography and computed tomography in patients with extrahepatic CPSS.

Hepatic focal nodular hyperplasia with congenital portosystemic shunt

“…In order to evaluate the shunt severity in addition to the presence of PSS, per-rectal portal scintigraphy using 99m Tc-pertechnetate was performed, and the amount of radionuclide shunting the liver and reaching the systemic blood after injection into the rectum was measured as described previously. 6 On per-rectal portal scintigraphy shunt index was elevated, at 21.4% (cut-off >10%), thus supporting the presence of intrahepatic PSS. At patient age 12 months, laboratory examination showed mild elevation of liver enzymes (AST, 72 IU/L; ALT, 58 IU/L), total bilirubin, 0.2 mg/dL, TBA, 33.3 μmol/L; GGTP, 36 IU/L; α-fetoprotein, 7.4 ng/mL; and ammonia, 69 μg/dL.…”

“…a). In order to evaluate the shunt severity in addition to the presence of PSS, per‐rectal portal scintigraphy using 99m Tc‐pertechnetate was performed, and the amount of radionuclide shunting the liver and reaching the systemic blood after injection into the rectum was measured as described previously . On per‐rectal portal scintigraphy shunt index was elevated, at 21.4% (cut‐off >10%), thus supporting the presence of intrahepatic PSS.…”

Presentation of Congenital Portosystemic Shunts in Children

“…Imaging can be used to measure shunt size. Per-rectal scintigraphy may provide indirect quantification of the shunt ratio (also called shunt fraction or shunt index), i.e., the degree of flow traversing the shunt [ 1 , 12 , 87 , 88 ]. How this ratio is related to clinical signs and symptoms is unclear and still a matter of debate among experts.…”

Congenital portosystemic venous shunt

“…Shunt ratios of greater than 5% were considered abnormal [ 13 , 15 ]. This method has gradually been replaced by the Doppler ultrasound although one study demonstrated (Yuki Cho et al) superiority in the estimation of shunt severity using rectal scintigraphy [ 12 , 14 , 52 ].…”