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Multiparametric MRI of Epiphyseal Cartilage Necrosis (Osteochondrosis) with Histological Validation in a Goat Model.

Wang L, Nissi MJ, Tóth F, Shaver J, Johnson CP, Zhang J, Garwood M, Carlson CS, Ellermann JM - PLoS ONE (2015)

Bottom Line: All relaxation time constants differentiated normal epiphyseal cartilage from lesions of ischemic cartilage necrosis, and the histological staining results confirmed the proteoglycan (PG) loss in the areas of ischemia.In the scanned specimens, all of the measured relaxation time constants were higher in the articular than in the normal epiphyseal cartilage, consistently allowing differentiation between these two tissues.Multiparametric MRI provided a sensitive approach to discriminate between necrotic and viable epiphyseal cartilage and between articular and epiphyseal cartilage, which may be useful for diagnosing and monitoring OC lesions and, potentially, for assessing effectiveness of treatment interventions.

View Article: PubMed Central - PubMed

Affiliation: Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, United States of America; Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, MN, United States of America.

ABSTRACT

Purpose: To evaluate multiple MRI parameters in a surgical model of osteochondrosis (OC) in goats.

Methods: Focal ischemic lesions of two different sizes were induced in the epiphyseal cartilage of the medial femoral condyles of goats at 4 days of age by surgical transection of cartilage canal blood vessels. Goats were euthanized and specimens harvested 3, 4, 5, 6, 9 and 10 weeks post-op. Ex vivo MRI scans were conducted at 9.4 Tesla for mapping the T1, T2, T1ρ, adiabatic T1ρ and TRAFF relaxation times of articular cartilage, unaffected epiphyseal cartilage, and epiphyseal cartilage within the area of the induced lesion. After MRI scans, safranin O staining was conducted to validate areas of ischemic necrosis induced in the medial femoral condyles of six goats, and to allow comparison of MRI findings with the semi-quantitative proteoglycan assessment in corresponding safranin O-stained histological sections.

Results: All relaxation time constants differentiated normal epiphyseal cartilage from lesions of ischemic cartilage necrosis, and the histological staining results confirmed the proteoglycan (PG) loss in the areas of ischemia. In the scanned specimens, all of the measured relaxation time constants were higher in the articular than in the normal epiphyseal cartilage, consistently allowing differentiation between these two tissues.

Conclusions: Multiparametric MRI provided a sensitive approach to discriminate between necrotic and viable epiphyseal cartilage and between articular and epiphyseal cartilage, which may be useful for diagnosing and monitoring OC lesions and, potentially, for assessing effectiveness of treatment interventions.

No MeSH data available.


Related in: MedlinePlus

Parametric MRI images of femoral condyle.Relaxation time maps for (A, E) T2, (B, F) T1ρ, (C, G) adiabatic T1ρ, and (D, H) TRAFF in the medial condyle of the distal femur at 5 weeks (top row, large lesion) and 6 weeks (bottom row, small lesion) post-surgically. Lesion locations are indicated by the arrows in the T2 maps.
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pone.0140400.g004: Parametric MRI images of femoral condyle.Relaxation time maps for (A, E) T2, (B, F) T1ρ, (C, G) adiabatic T1ρ, and (D, H) TRAFF in the medial condyle of the distal femur at 5 weeks (top row, large lesion) and 6 weeks (bottom row, small lesion) post-surgically. Lesion locations are indicated by the arrows in the T2 maps.

Mentions: Two representative cases, one with a small incision (6 weeks post surgery) and one with a larger incision (5 weeks post surgery) were selected to illustrate the parametric MRI images (Fig 4). T2, T1ρ, adiabatic T1ρ, and TRAFF values were increased in the lesions compared to normal epiphyseal cartilage in both cases. T1 was not included in the figure due to its limited sensitivity to the induced necrosis. With the large incision, up to an 80% increase in the relaxation times made it easier to discriminate the necrotic from viable epiphyseal cartilage in the images (Table 4 and Fig 4). With the small incision, the relaxation times increased less, but the lesion could still be identified in the images, even though cartilage necrosis was not identified histologically and the PG loss was very limited (Tables 2 and 4 and Fig 4).


Multiparametric MRI of Epiphyseal Cartilage Necrosis (Osteochondrosis) with Histological Validation in a Goat Model.

Wang L, Nissi MJ, Tóth F, Shaver J, Johnson CP, Zhang J, Garwood M, Carlson CS, Ellermann JM - PLoS ONE (2015)

Parametric MRI images of femoral condyle.Relaxation time maps for (A, E) T2, (B, F) T1ρ, (C, G) adiabatic T1ρ, and (D, H) TRAFF in the medial condyle of the distal femur at 5 weeks (top row, large lesion) and 6 weeks (bottom row, small lesion) post-surgically. Lesion locations are indicated by the arrows in the T2 maps.
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4608749&req=5

pone.0140400.g004: Parametric MRI images of femoral condyle.Relaxation time maps for (A, E) T2, (B, F) T1ρ, (C, G) adiabatic T1ρ, and (D, H) TRAFF in the medial condyle of the distal femur at 5 weeks (top row, large lesion) and 6 weeks (bottom row, small lesion) post-surgically. Lesion locations are indicated by the arrows in the T2 maps.
Mentions: Two representative cases, one with a small incision (6 weeks post surgery) and one with a larger incision (5 weeks post surgery) were selected to illustrate the parametric MRI images (Fig 4). T2, T1ρ, adiabatic T1ρ, and TRAFF values were increased in the lesions compared to normal epiphyseal cartilage in both cases. T1 was not included in the figure due to its limited sensitivity to the induced necrosis. With the large incision, up to an 80% increase in the relaxation times made it easier to discriminate the necrotic from viable epiphyseal cartilage in the images (Table 4 and Fig 4). With the small incision, the relaxation times increased less, but the lesion could still be identified in the images, even though cartilage necrosis was not identified histologically and the PG loss was very limited (Tables 2 and 4 and Fig 4).

Bottom Line: All relaxation time constants differentiated normal epiphyseal cartilage from lesions of ischemic cartilage necrosis, and the histological staining results confirmed the proteoglycan (PG) loss in the areas of ischemia.In the scanned specimens, all of the measured relaxation time constants were higher in the articular than in the normal epiphyseal cartilage, consistently allowing differentiation between these two tissues.Multiparametric MRI provided a sensitive approach to discriminate between necrotic and viable epiphyseal cartilage and between articular and epiphyseal cartilage, which may be useful for diagnosing and monitoring OC lesions and, potentially, for assessing effectiveness of treatment interventions.

View Article: PubMed Central - PubMed

Affiliation: Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, United States of America; Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, MN, United States of America.

ABSTRACT

Purpose: To evaluate multiple MRI parameters in a surgical model of osteochondrosis (OC) in goats.

Methods: Focal ischemic lesions of two different sizes were induced in the epiphyseal cartilage of the medial femoral condyles of goats at 4 days of age by surgical transection of cartilage canal blood vessels. Goats were euthanized and specimens harvested 3, 4, 5, 6, 9 and 10 weeks post-op. Ex vivo MRI scans were conducted at 9.4 Tesla for mapping the T1, T2, T1ρ, adiabatic T1ρ and TRAFF relaxation times of articular cartilage, unaffected epiphyseal cartilage, and epiphyseal cartilage within the area of the induced lesion. After MRI scans, safranin O staining was conducted to validate areas of ischemic necrosis induced in the medial femoral condyles of six goats, and to allow comparison of MRI findings with the semi-quantitative proteoglycan assessment in corresponding safranin O-stained histological sections.

Results: All relaxation time constants differentiated normal epiphyseal cartilage from lesions of ischemic cartilage necrosis, and the histological staining results confirmed the proteoglycan (PG) loss in the areas of ischemia. In the scanned specimens, all of the measured relaxation time constants were higher in the articular than in the normal epiphyseal cartilage, consistently allowing differentiation between these two tissues.

Conclusions: Multiparametric MRI provided a sensitive approach to discriminate between necrotic and viable epiphyseal cartilage and between articular and epiphyseal cartilage, which may be useful for diagnosing and monitoring OC lesions and, potentially, for assessing effectiveness of treatment interventions.

No MeSH data available.


Related in: MedlinePlus