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What sequences on high-field MR best depict temporal resolution of experimental ICH and edema formation in mice?

Li M, Akhavan-Sharif RM, Friedlander RM, Du R, Thiex R - J. Biomed. Biotechnol. (2012)

Bottom Line: Values were compared with morphometric analysis of cryosections at the time of final MR imaging.For hematoma quantitation, the Spearman correlation coefficient (r) between T1 signal change and histology was 0.70 (P < 0.04) compared with r = 0.61 (P < 0.09) for T2*.The extent of perihematomal edema formation on cryosections was well reflected on T2 with r = 0.73 (P < 0.03).

View Article: PubMed Central - PubMed

Affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.

ABSTRACT

Background and purpose: Pilot study to examine the use of T1-, T2-, and T2*-weighted images for evaluating hematoma size and extent of edema in mouse brain at high field.

Methods: Following collagenase-induced intracerebral hemorrhage, nine mice were imaged at 4.7 T using T1-, T2-, and T2*-weighted images for hematoma and edema quantitation on days 1, 3, 10, and 21 after surgery. Values were compared with morphometric analysis of cryosections at the time of final MR imaging.

Results: For hematoma quantitation, the Spearman correlation coefficient (r) between T1 signal change and histology was 0.70 (P < 0.04) compared with r = 0.61 (P < 0.09) for T2*. The extent of perihematomal edema formation on cryosections was well reflected on T2 with r = 0.73 (P < 0.03).

Conclusions: Within the limits of our pilot study, MR imaging on 4.7 T appears to approximate the temporal changes in hematoma and edema sizes in murine ICH well, thus laying the groundwork for longitudinal studies on hematoma resorption and edema formation.

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Related in: MedlinePlus

MR tomographic images on 4.7 T using T2*- (a, d, and g), T2- (b, e, and h), and T1-weighted images (c, f, and i) in a mouse 2 (a–c), 8 (d–f), and 24 hours (g–i) after stereotactic collagenase injection. The hematoma appears hypointense on T1 as early as 2 hours after collagenase injection and does not change in signal intensity and homogeneity over the first 24 hours. The blooming effect of T2*-weighted sequences makes the hematoma appear larger and needs referencing with T1- and T2-weighted images. T2-weighted images reveal a rim of hyperintensity surrounding the hypointense core as early as 8 hours. There is no evidence of hematoma enlargement over the first 24 hours.
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fig1: MR tomographic images on 4.7 T using T2*- (a, d, and g), T2- (b, e, and h), and T1-weighted images (c, f, and i) in a mouse 2 (a–c), 8 (d–f), and 24 hours (g–i) after stereotactic collagenase injection. The hematoma appears hypointense on T1 as early as 2 hours after collagenase injection and does not change in signal intensity and homogeneity over the first 24 hours. The blooming effect of T2*-weighted sequences makes the hematoma appear larger and needs referencing with T1- and T2-weighted images. T2-weighted images reveal a rim of hyperintensity surrounding the hypointense core as early as 8 hours. There is no evidence of hematoma enlargement over the first 24 hours.

Mentions: In two animals, MR imaging was performed as early as 2 hours after hematoma induction, and the hematoma was observed as a focal hypointensity on T1-, T2-, and T2*-weighted images. The hematoma remained stable without any evidence of expansion when scanned again 8 hours and 24 hours following collagenase injection (Figure 1).


What sequences on high-field MR best depict temporal resolution of experimental ICH and edema formation in mice?

Li M, Akhavan-Sharif RM, Friedlander RM, Du R, Thiex R - J. Biomed. Biotechnol. (2012)

MR tomographic images on 4.7 T using T2*- (a, d, and g), T2- (b, e, and h), and T1-weighted images (c, f, and i) in a mouse 2 (a–c), 8 (d–f), and 24 hours (g–i) after stereotactic collagenase injection. The hematoma appears hypointense on T1 as early as 2 hours after collagenase injection and does not change in signal intensity and homogeneity over the first 24 hours. The blooming effect of T2*-weighted sequences makes the hematoma appear larger and needs referencing with T1- and T2-weighted images. T2-weighted images reveal a rim of hyperintensity surrounding the hypointense core as early as 8 hours. There is no evidence of hematoma enlargement over the first 24 hours.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3351132&req=5

fig1: MR tomographic images on 4.7 T using T2*- (a, d, and g), T2- (b, e, and h), and T1-weighted images (c, f, and i) in a mouse 2 (a–c), 8 (d–f), and 24 hours (g–i) after stereotactic collagenase injection. The hematoma appears hypointense on T1 as early as 2 hours after collagenase injection and does not change in signal intensity and homogeneity over the first 24 hours. The blooming effect of T2*-weighted sequences makes the hematoma appear larger and needs referencing with T1- and T2-weighted images. T2-weighted images reveal a rim of hyperintensity surrounding the hypointense core as early as 8 hours. There is no evidence of hematoma enlargement over the first 24 hours.
Mentions: In two animals, MR imaging was performed as early as 2 hours after hematoma induction, and the hematoma was observed as a focal hypointensity on T1-, T2-, and T2*-weighted images. The hematoma remained stable without any evidence of expansion when scanned again 8 hours and 24 hours following collagenase injection (Figure 1).

Bottom Line: Values were compared with morphometric analysis of cryosections at the time of final MR imaging.For hematoma quantitation, the Spearman correlation coefficient (r) between T1 signal change and histology was 0.70 (P < 0.04) compared with r = 0.61 (P < 0.09) for T2*.The extent of perihematomal edema formation on cryosections was well reflected on T2 with r = 0.73 (P < 0.03).

View Article: PubMed Central - PubMed

Affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.

ABSTRACT

Background and purpose: Pilot study to examine the use of T1-, T2-, and T2*-weighted images for evaluating hematoma size and extent of edema in mouse brain at high field.

Methods: Following collagenase-induced intracerebral hemorrhage, nine mice were imaged at 4.7 T using T1-, T2-, and T2*-weighted images for hematoma and edema quantitation on days 1, 3, 10, and 21 after surgery. Values were compared with morphometric analysis of cryosections at the time of final MR imaging.

Results: For hematoma quantitation, the Spearman correlation coefficient (r) between T1 signal change and histology was 0.70 (P < 0.04) compared with r = 0.61 (P < 0.09) for T2*. The extent of perihematomal edema formation on cryosections was well reflected on T2 with r = 0.73 (P < 0.03).

Conclusions: Within the limits of our pilot study, MR imaging on 4.7 T appears to approximate the temporal changes in hematoma and edema sizes in murine ICH well, thus laying the groundwork for longitudinal studies on hematoma resorption and edema formation.

Show MeSH
Related in: MedlinePlus