Role of imaging techniques in liver veno-occlusive disease diagnosis: recent advances and literature review.

INTRODUCTION: Veno-occlusive-disease (VOD), known also as sinusoidal-obstruction-syndrome (SOS), is one of the main complications of haematopoietic stem cell transplantation and is related to the treatment with pyrrolizidine alkaloids or other toxic agents (chemotherapy for liver-metastasis). Clinical diagnosis using the recent criteria from the European Society for Blood and Marrow Transplantation, is the reference for VOD/SOS diagnosis. However, increasing evidence suggests the emerging role of several imaging methods that could help the clinician in VOD/SOS assessment. Areas covered: This review evaluates the current literature on the various imaging techniques used in VOD/SOS diagnosis in several clinical scenarios. Literature searches were performed using several keywords on MEDLINE/Ovid/In-Process/Cochrane Library/EMBASE and PubMed up to July 2018. Expert commentary: Hepatic-gradient-measurement (HVPG) and contextual transjugular-liver-biopsy are invasive and should always be considered in unclear cases. The main studies revolve around ultrasound with Doppler evaluation, identifying numerous findings suggestive of VOD/SOS. However, their accuracy and validation are still suboptimal and controversial. CT-Scan and MRI have shown encouraging data in other contexts in which VOD/SOS can develop, but studies on the post-HSCT patient are lacking. Elastography techniques measuring liver stiffness (LSM) represent the most recent and promising approach for an accurate and early diagnosis of VOD/SOS. In our view, a multidisciplinary approach to the VOD/SOS diagnosis should be highly encouraged.