Accuracy of Ultrasound Exam, Including Doppler and Elastography, in the Diagnosis of VOD, Following Bone Marrow Transplantation

The purpose of the study: Validation of the use of intentional ultrasound examination, which includes Doppler and elastography for the diagnosis of obstructive venous disease of the liver within 21 days after bone marrow transplantation. Protocol: Patients who are planned for a bone marrow transplantaion will be recruited for the study by the staff of the Transplant Department. Inclusion criteria: Patients over the age of 18 before a bone marrow transplantation. Eligibility criteria: Transplanted under 18 years of age Research protocol: After informed consent, patients will undergo an ultrasound examination before the transplant. The test will include: 1. Demonstration of liver including its size. 2. Gallbladder demonstration including its width and wall thickness. 3. Main portal vein width, Speed and flow direction in main portal vein. 4. Evaluation of umbilical vein in the falciform ligament to check existence of flow and venous width in case it opened. 5. Assessment of existence a small / medium or large amount of ascites measurement of resistance index in the main hepatic artery. 6. Complete elastography examination. After 14 days and again after 21 days patients will undergo two more US exams, If there is a change in their clinical condition the patients will undergo additional examination accordingly. At the same time on the 14th and 21st day a clinical evaluation will be performed by the clinical physician in the transplant department based on clinical criteria of European Blood and Brain Transplant Association (EBMT). The results of the clinical evaluation and blood test results will be collected. Patients will be divided into two groups: * Control group: Patients who did not develop VOD( veno occlusive disease ) during 21 days. * Study group: Patients who developed VOD during 21 days. All ultrasound examination data will be compared between the two groups in In addition will be collected: * Demographics - age, sex. * Background diseases including heart and liver diseases. * Basic disease as a transplantation cause. All data will be collected anonymously and coded separately.