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T1ρ MRI of healthy and fibrotic human livers at 1.5 T.

Singh A, Reddy D, Haris M, Cai K, Rajender Reddy K, Hariharan H, Reddy R - J Transl Med (2015)

Bottom Line: T1ρ values in fibrotic liver were significantly higher compared to those of healthy liver (p < 0.05).Proposed T1ρ pulse sequence design and protocol enabled acquisition of a single slice T1ρ weighted images in a single breath-hold and hence mitigated breathing motion related artifacts.Further, studies on a large number of subjects are required to validate the observations of the current study.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, CMROI, University of Pennsylvania, Philadelphia, PA, USA. anups.minhas@gmail.com.

ABSTRACT

Background: Liver fibrosis is a public health problem worldwide. There is a need of noninvasive imaging based methods for better diagnosis of this disease. In the current study, we aim to evaluate the potential of T1ρ MRI technique in detecting and characterizing different grades of liver fibrosis in vivo in humans.

Methods: Healthy subjects and patients with liver fibrosis were prospectively recruited for T1ρ MRI of liver on a 1.5 T MR scanner. Single slice T1ρ weighted images were acquired at different spin lock duration (0, 10, 20 and 30 ms) with spin lock amplitude of 500 Hz in a single breath-hold. Additionally, liver's T1ρ images were acquired from five healthy subjects on the same day (n = 2) and different day (n = 2) sessions for test-retest study. Liver biopsy samples from patients were obtained and used to calculate the METAVIR score to define the stage of fibrosis and inflammation grade. T1ρ maps were generated followed by computation of mean and standard deviation (SD) values. Coefficient of variation (COV) of T1ρ values between two MRI scans was computed to determine reproducibility in liver. T test was used to compare T1ρ values between healthy and fibrotic liver. Pearson correlation was performed between stages of liver fibrosis and T1ρ values.

Results: The mean (SD) T1ρ value among subject with healthy liver was 51.04 (3.06) ms. The COV of T1ρ values between two repetitions in the same day session was 0.83 ± 0.8% and in different day session was 5.4 ± 2.7%. T1ρ values in fibrotic liver were significantly higher compared to those of healthy liver (p < 0.05). A statically significant correlation between stages of fibrosis and T1ρ values was observed (r = 0.99, p < 0.05). Inflammation score for one patient was 2 and for remaining patients it was 1.

Conclusions: Proposed T1ρ pulse sequence design and protocol enabled acquisition of a single slice T1ρ weighted images in a single breath-hold and hence mitigated breathing motion related artifacts. Preliminary results have shown the sensitivity of T1ρ values to changes induced by liver fibrosis, and may potentially be used as a clinical biomarker to delineate the stages of liver fibrosis. Further, studies on a large number of subjects are required to validate the observations of the current study. Nevertheless, T1ρ imaging can be easily setup on a clinical scanner to monitor the progression of liver fibrosis and to the evaluate efficacy of anti-fibrotic drugs.

No MeSH data available.


Related in: MedlinePlus

T1ρ weighted image corresponding to TSL = 30 ms (a) and map (b) of patient liver having stage-0 fibrosis and inflammation grade equal to 1. T1ρ map of segmented liver is color overlaid on anatomical image. T1ρ values in ROI marked on weighted image (a) is 73 ± 9 ms. White arrow points to liver tissue with partial volume to kidney
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Fig4: T1ρ weighted image corresponding to TSL = 30 ms (a) and map (b) of patient liver having stage-0 fibrosis and inflammation grade equal to 1. T1ρ map of segmented liver is color overlaid on anatomical image. T1ρ values in ROI marked on weighted image (a) is 73 ± 9 ms. White arrow points to liver tissue with partial volume to kidney

Mentions: Figure 4 show T1ρ map of patient, having stage-0 fibrosis and inflammation grade equal to 1, based upon METAVIR scale. For this subject elevated T1ρ values were observed all across the liver compared to healthy subject’s liver. In fact T1ρ value for this subject was higher compared to average values in group-3 also. However, the overall T1ρ map of liver, except blood vessels, was homogeneous. During analysis, in stage-0 we have included all the healthy subjects and this subject’s data was excluded from analysis.Fig. 4


T1ρ MRI of healthy and fibrotic human livers at 1.5 T.

Singh A, Reddy D, Haris M, Cai K, Rajender Reddy K, Hariharan H, Reddy R - J Transl Med (2015)

T1ρ weighted image corresponding to TSL = 30 ms (a) and map (b) of patient liver having stage-0 fibrosis and inflammation grade equal to 1. T1ρ map of segmented liver is color overlaid on anatomical image. T1ρ values in ROI marked on weighted image (a) is 73 ± 9 ms. White arrow points to liver tissue with partial volume to kidney
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4562204&req=5

Fig4: T1ρ weighted image corresponding to TSL = 30 ms (a) and map (b) of patient liver having stage-0 fibrosis and inflammation grade equal to 1. T1ρ map of segmented liver is color overlaid on anatomical image. T1ρ values in ROI marked on weighted image (a) is 73 ± 9 ms. White arrow points to liver tissue with partial volume to kidney
Mentions: Figure 4 show T1ρ map of patient, having stage-0 fibrosis and inflammation grade equal to 1, based upon METAVIR scale. For this subject elevated T1ρ values were observed all across the liver compared to healthy subject’s liver. In fact T1ρ value for this subject was higher compared to average values in group-3 also. However, the overall T1ρ map of liver, except blood vessels, was homogeneous. During analysis, in stage-0 we have included all the healthy subjects and this subject’s data was excluded from analysis.Fig. 4

Bottom Line: T1ρ values in fibrotic liver were significantly higher compared to those of healthy liver (p < 0.05).Proposed T1ρ pulse sequence design and protocol enabled acquisition of a single slice T1ρ weighted images in a single breath-hold and hence mitigated breathing motion related artifacts.Further, studies on a large number of subjects are required to validate the observations of the current study.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, CMROI, University of Pennsylvania, Philadelphia, PA, USA. anups.minhas@gmail.com.

ABSTRACT

Background: Liver fibrosis is a public health problem worldwide. There is a need of noninvasive imaging based methods for better diagnosis of this disease. In the current study, we aim to evaluate the potential of T1ρ MRI technique in detecting and characterizing different grades of liver fibrosis in vivo in humans.

Methods: Healthy subjects and patients with liver fibrosis were prospectively recruited for T1ρ MRI of liver on a 1.5 T MR scanner. Single slice T1ρ weighted images were acquired at different spin lock duration (0, 10, 20 and 30 ms) with spin lock amplitude of 500 Hz in a single breath-hold. Additionally, liver's T1ρ images were acquired from five healthy subjects on the same day (n = 2) and different day (n = 2) sessions for test-retest study. Liver biopsy samples from patients were obtained and used to calculate the METAVIR score to define the stage of fibrosis and inflammation grade. T1ρ maps were generated followed by computation of mean and standard deviation (SD) values. Coefficient of variation (COV) of T1ρ values between two MRI scans was computed to determine reproducibility in liver. T test was used to compare T1ρ values between healthy and fibrotic liver. Pearson correlation was performed between stages of liver fibrosis and T1ρ values.

Results: The mean (SD) T1ρ value among subject with healthy liver was 51.04 (3.06) ms. The COV of T1ρ values between two repetitions in the same day session was 0.83 ± 0.8% and in different day session was 5.4 ± 2.7%. T1ρ values in fibrotic liver were significantly higher compared to those of healthy liver (p < 0.05). A statically significant correlation between stages of fibrosis and T1ρ values was observed (r = 0.99, p < 0.05). Inflammation score for one patient was 2 and for remaining patients it was 1.

Conclusions: Proposed T1ρ pulse sequence design and protocol enabled acquisition of a single slice T1ρ weighted images in a single breath-hold and hence mitigated breathing motion related artifacts. Preliminary results have shown the sensitivity of T1ρ values to changes induced by liver fibrosis, and may potentially be used as a clinical biomarker to delineate the stages of liver fibrosis. Further, studies on a large number of subjects are required to validate the observations of the current study. Nevertheless, T1ρ imaging can be easily setup on a clinical scanner to monitor the progression of liver fibrosis and to the evaluate efficacy of anti-fibrotic drugs.

No MeSH data available.


Related in: MedlinePlus