Massive Iron Deposit Assessment

Summary

Iron overload is a severe complication of multiple blood transfusions. As the body has no physiologic mechanism for clearing iron, repeated transfusions cause iron accumulation in organs and lead to iron toxicity. Accurate assessment of iron overload is paramount to quantify excessive iron accumulation and to monitor response to iron chelation therapy. Magnetic resonance imaging (MRI) methods have been used to noninvasively measure hepatic iron concentration (HIC). Although MRI-based measurements of transverse relaxation rates (R2 and R2\*) accurately predict biopsy-proven HICs below 15 mg Fe/g, previous studies have shown that their precision is limited for HICs above 15 mg Fe/g and inaccurate above 25 mg Fe/g. Current R2\* gradient-echo (GRE) MR techniques fail occasionally for very high iron overloads (HIC \~ 15-25 mg Fe/g) and always for massive iron overloads (HIC \> 25 mg Fe/g) because R2\* is so high that the MR signal decays before it can be measured accurately.

Overall accrual: 200 patients

Purpose: To determine if a new MRI (UTE) can measure the amount of iron in the liver of people with large amounts of iron and compare the results with the same patient's liver bx. Estimated patient accrual is 150. It is estimated that 41 of these patients will have clinical indication for liver biopsy.

Conditions

• Iron Overload
• Excessive Body Iron Burden

Interventions

DEVICE

R2*-UTE

Ultra short echo time (UTE) magnetic resonance imaging (MRI). Study participants will undergo an MRI examination of the liver on a 1.5T MRI and a 3T MRI scanner each. Because liver biopsy metal needle fragments could interfere with the MRI measurements, the MRI exams will always precede liver biopsy. Multi-echo GRE sequences will be used to acquire images with increasing TEs. Images of the liver will be obtained in transversal slice orientation through the center of the liver at the level of the origin of the main portal vein. At equivalent slice locations R2\*-UTE scans will be performed.

DEVICE

R2*-GRE

Gradient-echo (GRE) magnetic resonance imaging (MRI). Study participants will undergo an MRI examination of the liver on a 1.5T MRI and a 3T MRI scanner each. Because liver biopsy metal needle fragments could interfere with the MRI measurements, the MRI exams will always precede liver biopsy. Multi-echo GRE sequences will be used to acquire images with increasing TEs. Images of the liver will be obtained in transversal slice orientation through the center of the liver at the level of the origin of the main portal vein. At equivalent slice locations R2\*-UTE scans will be performed.

PROCEDURE

Liver biopsy

Indications for liver biopsy include, but are not limited, to the need to quantify liver tissue iron and the need to obtain histopathological information of the liver tissue. Liver biopsies will only be performed if clinically indicated and will be done only once per patient. The technique to be used is coaxial percutaneous (transcapsular) technique; however, a coaxial transjugular technique may be performed in subjects with increased bleeding diathesis, since it is associated with less hemorrhagic risk. Healthy volunteers will not undergo liver biopsy.

Sponsors & Collaborators

• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

  collaborator NIH

• Regional One Health

  collaborator OTHER

• St. Jude Children's Research Hospital

  lead OTHER

Principal Investigators

• Jane Hankins, MD, MS · St. Jude Children's Research Hospital

Study Design

Allocation

NA

Purpose

DIAGNOSTIC

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2012-06-11

Primary Completion

2018-02-28

Completion

2018-02-28

FDA Device

Yes

Countries

• United States

Study Locations