Purpose: Sinusoidal obstruction syndrome (SOS)/hepatic veno-occlusive disease (VOD) is a fatal complication after hematopoietic stem cell transplantation. We previously reported the usefulness of an ultrasonographical (US) scoring system, the Hokkaido US-based scoring system consisting of ten parameters (HokUS-10): (1) hepatomegaly in the left lobe and (2) right lobe, (3) dilatation of the main portal vein (PV), (4) hepatofugal flow in the main PV, (5) decreased velocity of the PV, (6) dilatation of the para-umbilical vein (PUV), (7) appearance of blood flow signal in the PUV, (8) gallbladder (GB) wall thickening, (9) ascites, and (10) increased resistive index of the hepatic artery, for the diagnosis of SOS/VOD. However, the reliability of this system among operators remains elusive. Therefore, we prospectively evaluated the reliability of HokUS-10.
Methods: Twenty-four healthy volunteers and 40 patients with liver dysfunction were enrolled. Inter- and intra-operator reliabilities were analyzed using three sonographers.
Results: The median concordance rate of HokUS-10 among three sonographers and intra-operator in 24 volunteers was 92% (95% CI: 73-98%) and 98% (95% CI: 92-100%), respectively. In all 64 cases, in terms of the reliability between two sonographers for three representative US parameters (amount of ascites, GB wall thickening, and appearance of PUV blood flow signal), the median concordance rate was more than 98% (95% CI: 86-106%).
Conclusion: The inter- and intra-reliabilities of HokUS-10 were excellent. Thus, US might be a reliable tool for SOS/VOD diagnosis.
Keywords: Hematopoietic stem cell transplantation; Hepatic veno-occlusive disease; Operator reliability; Sinusoidal obstruction syndrome; Ultrasonography.