AJR 2003; 181:761-769
© American Roentgen Ray Society
Hypointense Synovial Lesions on T2-Weighted Images: Differential Diagnosis with Pathologic Correlation
José A. Narváez1,
Javier Narváez2,3,
Raúl Ortega1,
Eugenia De Lama1,
Yolanda Roca1 and
Noemí Vidal4
1 Department of MR Imaging and Radiology, Institut de Diagnòstic per la
Imatge, Hospital Duran i Reynals, Ciutat Sanitària i
Universitària de Bellvitge, Autovía de Castelldefels, km 2'7,
L'Hospitalet de Llobregat, 08907 Barcelona, Spain.
2 Department of Rheumatology, Ciutat Sanitària i Universitària de
Bellvitge, 08907 Barcelona, Spain.
3 Rheumatologic Unit, Department of Medicine, Clínica Delfos, 08023
Barcelona, Spain.
4 Department of Pathology, Ciutat Sanitària i Universitària de
Bellvitge, 08907 Barcelona, Spain.
Received June 6, 2002;
accepted after revision December 31, 2002.
Address correspondence to J. A. Narváez.
Introduction
Synovial tissue that lines joint cavities, bursae, and tendinous sheaths is
generally too thin to be shown on MRI. However, as synovial tissue thickens
because of diverse abnormal conditions, it may become visible on MRI. Signal
intensity is a feature of paramount importance in the MRI assessment of these
synovial lesions. For T2-weighted images, fat is the tissue usually used for
comparison [1]; thus,
hypointense lesions have a lower signal compared with adjacent fat tissue on
conventional spin-echo T2-weighted images. It is important to recognize that
fat-suppressed T2-weighted or short tau inversion recovery images should not
replace conventional spin-echo or fast spin-echo T2-weighted images in the
evaluation of patients with soft-tissue masses or masslike lesions because
assessment of the signal intensity is usually based on the findings of
conventional spin-echo T2-weighted
images.
View larger version (177K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4D. —Dialysis-related amyloid arthropathy of hip in 65-year-old
man. Photomicrograph of specimen shows that amyloid deposits
(asterisks) have an affinity for Congo red stain on light microscopy.
(Congo red, x200)
|
|
View larger version (184K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4E. —Dialysis-related amyloid arthropathy of hip in 65-year-old
man. Photomicrograph of specimen shows that abnormal material is characterized
by apple green birefringence (asterisks) under polarized light.
Hypocellular and fibrous nature of this amyloid-containing tissue explains low
signal intensity on T2-weighted MR images. (Congo red, x250)
|
|
The purpose of this pictorial essay is to illustrate the spectrum of MRI
features of hypointense synovial lesions on T2-weighted images. Emphasis is
placed on clinical, radiographic, and MRI features that suggest a specific
diagnosis and on abnormal findings that explain the signal intensity of these
lesions.
Pigmented Villonodular Synovitis
Pigmented villonodular synovitis is a benign proliferative lesion of the
synovium that can appear in either a localized or diffuse form within the
joint. The localized form is often referred to as nodular synovitis and is
typically not associated with a joint effusion.
Pigmented villonodular synovitis most often occurs in young to middle-aged
adults. The knee is the most frequent joint involved, followed by the hip and
ankle [2]. Patients usually
present with pain, swelling, and limitation of motion. Pathologically,
pigmented villonodular synovitis is characterized by hyperplasia of the
synovial lining of cells with subsynovial infiltration by multinucleated giant
cells, hemosiderin-laden macrophages, foam cells, and fibroblasts.
Radiographic findings may be normal or may reveal periarticular soft-tissue
swelling. Joint space and bone density are characteristically preserved. Bone
erosions are frequent in joints with a tight capsule such as the hip, ankle,
and elbow [1].
On MRI, masslike synovial proliferations have lobulated margins and may be
extensive in the diffuse form of the disease or limited to a well-defined
single nodule in the localized form. The tendency of the lesions to bleed
results in deposition of hemosiderin. The paramagnetic effect of hemosiderin
results in the reduction of signal intensity in all pulse sequences
[1,
2], which is enhanced by
highfield-strength and gradient-echo sequences
[2] (Figs.
1A,
1B, and
1C). The reduction of signal
intensity is more accentuated on T2-weighted images. Hemosiderin deposition is
less in localized forms and may result in intermediate signal intensity on
T2-weighted images. Older lesions may present with synovial fibrosis that may
contribute to the low signal intensity on T2-weighted images.
View larger version (101K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1A. —Pigmented villonodular synovitis of knee in 32-year-old man.
Axial T2-weighted image (TR/TE, 2500/90) shows nodular thickening of synovium
of low signal intensity (arrows) occupying suprapatellar pouch. Note
small areas of very high signal intensity (asterisk) that correspond
to joint fluid.
|
|
View larger version (128K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1B. —Pigmented villonodular synovitis of knee in 32-year-old man.
Sagittal gradient-recalled echo T2*-weighted image (657/25; flip
angle, 25°) obtained through medial aspect of suprapatellar pouch shows
tissue of very low signal intensity (arrows) containing areas of high
signal intensity (asterisks). V = vastus medialis tendon.
|
|
View larger version (198K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1C. —Pigmented villonodular synovitis of knee in 32-year-old man.
Photomicrograph of histologic specimen shows that synovial villous hyperplasia
is covered by reactive-appearing synovial cells containing abundant reddish
brown hemosiderin (arrowheads). Arrows point to surface of synovial
lining. (H and E, x40)
|
|
However, areas of high signal intensity on T2-weighted images may be
present and are believed to be caused by inflamed synovium or effusion (Figs.
1A,
1B, and
1C).
Articular erosions present variable signal intensity that reflects the
presence of fluid, soft tissue, or hemosiderin
[2]. Pigmented villonodular
synovitis characteristically shows intense gadolinium enhancement, reflecting
the high vascularity of the synovial proliferation.
Giant Cell Tumor of the Tendon Sheath
Giant cell tumor of the tendon sheath represents the tenosynovial
counterpart of pigmented villonodular synovitis, which is more often seen in
women, usually in the third to fifth decades of life. The hand, especially the
fingers, is the most common location. Clinically, giant cell tumor of the
tendon sheath presents as a slowly enlarging painless mass. Radiographic
findings either are normal or show a nonspecific soft-tissue mass that may
uncommonly produce pressure erosions on the underlying bone.
MRI reveals a well-defined lobulated mass with a characteristic enveloping
growth pattern surrounding the affected tendon.
Hemosiderin deposition and abundant collagenous stroma of these lesions
cause low signal intensity on T2-weighted images
[1] (Figs.
2A, and
2B). Giant cell tumor of the
tendon sheath tends to bleed less than pigmented villonodular synovitis, and
thus, less hemosiderin and lesser reduction of signal intensity are seen on
MRI. Therefore, the signal intensity of giant cell tumor of the tendon sheath
on T2-weighted imaging is intermediate to low. Similar to pigmented
villonodular synovitis, giant cell tumor of the tendon sheath shows strong
gadolinium enhancement.
View larger version (83K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2A. —Giant cell tumor of tendon sheath in 39-year-old man.
Sagittal T1-weighted image (TR/TE, 600/25) shows ovoid well-defined mass at
distal volar aspect of thumb (arrows) adjacent to superficial border
of flexor tendon. Signal intensity is heterogeneous, with areas of
intermediate and high signal intensity interspersed between zones of low
signal intensity. Note small pressure erosion in distal phalanx
(arrowheads).
|
|
View larger version (87K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2B. —Giant cell tumor of tendon sheath in 39-year-old man.
Sagittal gradient-recalled echo T2*-weighted image (657/25; flip
angle, 25°) shows overall decreased signal intensity of lesion
(arrows) with only small areas of intermediate signal.
|
|
Hemophilic Arthropathy
Hemophilia is a coagulation defect caused by a functional or absolute
deficiency of a clotting factor. Classic hemophilia (hemophilia A) caused by
deficiency of antihemophilic factor (factor VIII) and Christmas disease
(hemophilia B) caused by deficiency of plasma thromboplastin component (factor
IX) are the most common forms. This group of blood disorders is X-linked
recessive and primarily affects males.
Hemophilic arthropathy is the most common musculoskeletal complication of
hemophilia and usually appears in the first two decades of life
[2]. The knee, elbow, and ankle
are the most frequently affected joints, usually in a bilateral fashion.
Hemophilic arthropathy is caused by repeated bleeding into the synovial
joints, which leads to the absorption of hemosiderin and blood products by the
synovium, synovial hypertrophy, chronic inflammatory changes, and fibrosis
[2]. Cartilage destruction and
secondary joint space narrowing occur in the chronic stage of the disease.
The absence of foam cells and multinucleated giant cells differentiates the
pathologic features of hemophilic arthropathy from those of pigmented
villonodular synovitis.
Radiographic findings vary with the age (skeletal maturity) of the patient
and the stage of joint disease. Radiographic findings include radiodense
effusions; regional or periarticular osteoporosis; subchondral bone erosions
and cysts; and, lately, joint space narrowing and osteophytosis
[2].
On MRI, hemophilic arthropathy shows synovial hypertrophy with low to
intermediate signal intensity on both T1- and T2-weighted images as a result
of synovial fibrosis and hemosiderin deposition
[2] (Figs.
3A, and
3B). Signal intensity of
subchondral bone cysts reflects the relative amount of blood, fluid, or
fibrosis.
View larger version (123K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3A. —Hemophilic arthropathy of ankle in 29-year-old man. Coronal
T1-weighted image (TR/TE, 500/25) (A) and gradient-recalled
T2*-weighted image (616/27; flip angle, 20°) (B) show
end-stage changes of disease in tibiotalar and subtalar joints with extensive
cartilage destruction, subchondral cysts, and secondary degenerative changes.
Note that low-signal synovial hemosiderin deposition (arrows) is
better seen on B.
|
|
View larger version (118K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3B. —Hemophilic arthropathy of ankle in 29-year-old man. Coronal
T1-weighted image (TR/TE, 500/25) (A) and gradient-recalled
T2*-weighted image (616/27; flip angle, 20°) (B) show
end-stage changes of disease in tibiotalar and subtalar joints with extensive
cartilage destruction, subchondral cysts, and secondary degenerative changes.
Note that low-signal synovial hemosiderin deposition (arrows) is
better seen on B.
|
|
Dialysis-Related Amyloid Arthropathy
Amyloid arthropathy is a complication of long-term hemodialysis. It is
caused by the synovial, osseous, and periarticular deposition of a unique form
of amyloid derived from circulating ß2-microglobulin. Serum
levels of ß2-microglobulin are increased in hemodialysis
patients because of the failure of hemodialysis and peritoneal dialysis
membranes to filter the substance.
Clinically, dialysis-related amyloid arthropathy manifests as a symmetric
polyarthritis, with pain and juxtaarticular swelling that usually involves the
shoulders, hips, wrists, and knees. Carpal tunnel syndrome or a rapidly
progressive destructive spondyloarthropathy that resembles infectious
spondylitis may be associated.
Radiographic findings include lobulated soft-tissue swelling, periarticular
osteoporosis, and multiple well-defined subchondral cystic lesions
[2]
(Fig. 4A). Sometimes, these
cystic lesions may produce fractures
[2].
View larger version (111K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4A. —Dialysis-related amyloid arthropathy of hip in 65-year-old
man. Oblique radiograph of pelvis reveals soft-tissue swelling around hip in
association with pressure bone erosions (arrows) and subchondral
cysts (arrowheads).
|
|
On MRI, synovial amyloid deposition shows a heterogeneously low signal on
both T1- and T2-weighted images
[2,
3] (Figs.
4B and
4C). The short T2 relaxation
time is probably caused by the hypocellular and fibrous nature of
amyloid-containing tissues [3].
Synovial amyloid deposition does not show paramagnetic effect on gradient-echo
sequences. This fact may be helpful in the differential diagnosis of synovial
conditions characterized by hemosiderin deposition as a result of the lesional
tendency to bleed. Subchondral cysts usually have the same signal intensity as
the infiltrated synovium. Joint or periarticular bursal effusion may be
present. Periarticular tendinous thickening caused by amyloid deposition is
another distinctive MRI feature (Figs.
5A, and
5B).
View larger version (121K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4B. —Dialysis-related amyloid arthropathy of hip in 65-year-old
man. Axial proton density-weighted (B) and T2-weighted (C) fast
spin-echo images (TR/TE range, 2484/25-110) show diffuse synovial thickening
distending hip capsule (white arrows). Signal intensity of synovium
is intermediate to low on proton density-weighted image and low on T2-weighted
image. Tissue-filling bone erosion of femoral neck (arrowheads) shows
similar signal intensity. Note also small periarticular fluid collection
(black arrow).
|
|
View larger version (124K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4C. —Dialysis-related amyloid arthropathy of hip in 65-year-old
man. Axial proton density-weighted (B) and T2-weighted (C) fast
spin-echo images (TR/TE range, 2484/25-110) show diffuse synovial thickening
distending hip capsule (white arrows). Signal intensity of synovium
is intermediate to low on proton density-weighted image and low on T2-weighted
image. Tissue-filling bone erosion of femoral neck (arrowheads) shows
similar signal intensity. Note also small periarticular fluid collection
(black arrow).
|
|
View larger version (135K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 5A. —Dialysis-related amyloid arthropathy of shoulder in
56-year-old woman. Axial gradient-recalled echo T2*-weighted images
(TR/TE, 709/28; flip angle, 40°) show marked thickening of subscapular and
infraspinatus tendons (arrowheads) that remain of low signal
intensity. Also note low-signal-intensity synovial and capsular ligamentous
thickening (asterisks).
|
|
View larger version (137K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 5B. —Dialysis-related amyloid arthropathy of shoulder in
56-year-old woman. Axial gradient-recalled echo T2*-weighted images
(TR/TE, 709/28; flip angle, 40°) show marked thickening of subscapular and
infraspinatus tendons (arrowheads) that remain of low signal
intensity. Also note low-signal-intensity synovial and capsular ligamentous
thickening (asterisks).
|
|
Synovial Chondromatosis
Synovial chondromatosis occurs most frequently in the third to fifth
decades of life, and men are affected approximately two to four times more
frequently than women. The knee, hip, and elbow are the most frequently
involved joints. Joint pain, swelling, and limitation of motion are the most
common complaints.
Synovial chondromatosis is the result of self-limiting proliferative and
metaplastic changes in the synovium. Three phases of the disease are
identified: an initial phase with metaplastic cartilaginous masses within the
synovium; a transitional phase with cartilaginous nodules detached from the
involved synovium forming free bodies (Figs.
6A,
6B,
6C, and
6D); and an inactive phase in
which the synovial proliferation has resolved but loose bodies remain, usually
with variable amounts of joint fluid. Cartilaginous nodules may become either
calcified or ossified, which is termed by some authors as "synovial
osteochondromatosis." Calcification is absent in 15-30% of the
cases.
View larger version (115K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 6A. —Synovial osteochondromatosis of knee in 46-year-old woman.
Lateral radiograph reveals well-defined soft-tissue opacity in popliteal
region (small white arrows). Note also faintly mineralized loose
bodies in posterior capsular recess (black arrow) and suprapatellar
pouch (large white arrow).
|
|
View larger version (132K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 6B. —Synovial osteochondromatosis of knee in 46-year-old woman.
Sagittal T2-weighted images (TR/TE, 2500/90) show well-defined synovial masses
(short white arrows) and loose bodies in posterior joint recess
(black arrow, B) and suprapatellar pouch (long white
arrows, C). Synovial masses present as predominantly high signal
intensity, but areas of intermediate to low signal intensity
(arrowheads) are seen. Calcified loose bodies show low signal
intensity.
|
|
View larger version (136K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 6C. —Synovial osteochondromatosis of knee in 46-year-old woman.
Sagittal T2-weighted images (TR/TE, 2500/90) show well-defined synovial masses
(short white arrows) and loose bodies in posterior joint recess
(black arrow, B) and suprapatellar pouch (long white
arrows, C). Synovial masses present as predominantly high signal
intensity, but areas of intermediate to low signal intensity
(arrowheads) are seen. Calcified loose bodies show low signal
intensity.
|
|
View larger version (161K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 6D. —Synovial osteochondromatosis of knee in 46-year-old woman.
High-power photomicrograph of histopathologic specimen shows synovial
cartilaginous nodules (asterisks) and areas in which bone is
beginning to develop with osteocytes secreting pink-staining osteoid matrix
(arrowheads). Ossified areas in which osteoid matrix has already
undergone mineralization (arrows) are also shown; these arrows
correspond to low-signal areas seen on T2-weighted images. (H and E,
x200)
|
|
Radiographs may be unremarkable or show an intraarticular mass with
multiple calcified nodules, characteristically uniform in size
(Fig. 6A).
The MRI appearance is variable and depends on the relative preponderance of
synovial proliferation and loose bodies formation and on the extent of
calcification or ossification
[2,
4,
5]. Synovial masses of
lobulated borders, with or without associated intraarticular loose bodies, are
the most common MRI finding [4,
5]. Unmineralized synovial
masses exhibit high signal intensity on T2-weighted images, reflecting hyaline
cartilage content. Foci of signal void due to mineralization within synovial
masses are common (Figs. 6A,
6B,
6C, and
6D) but only sometimes show
low signal intensity on T2-weighted images. Signal voids are more conspicuous
on gradient-echo sequences.
Calcified loose bodies appear as a nodular signal void (Figs.
6A,
6B,
6C, and
6D), whereas ossified loose
bodies show signal intensity characteristics of marrow fat centrally and of
cortical bone peripherally.
Long-Standing Rheumatoid Arthritis
Rheumatoid arthritis is characterized by a proliferative, hyperplastic,
hypervascular, and locally invasive synovial reaction called pannus. Fibrous
pannus tissue represents the end-stage of this synovial proliferation. In
fibrous pannus, the central region has evolved to a dense fibrous scar with
little vasculature, thus accounting for its low signal intensity on all pulse
sequences [6] (Figs.
7A, and
7B). Susceptibility artifacts
on gradient-echo sequences are not seen. Fibrous pannus appears relatively
hypovascular in both early and delayed phases after IV administration of
gadolinium.
View larger version (156K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 7A. —Fibrous rheumatoid pannus of ankle in 54-year-old woman.
Axial T2-weighted fast spin-echo image (TR/TE, 2350/110) shows anterior recess
of ankle joint filled with synovial tissue of low signal intensity
(asterisks) corresponding to fibrous pannus. It is surrounded by
high-signal-intensity areas (arrowheads) that correspond to
hypervascular pannus. t = distal tibia, f = distal fibula.
|
|
View larger version (133K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 7B. —Fibrous rheumatoid pannus of ankle in 54-year-old woman.
Axial fat-suppressed gadolinium-enhanced T1-weighted image (550/25)
(corresponding to A) shows enhancement of hypervascular pannus
(arrowheads). No enhancement of central fibrous pannus is present; it
remains of low signal intensity (asterisks). t = distal tibia, f =
distal fibula.
|
|
Chronic Tophaceous Gout
Tophi are local aggregations of urate crystals and a proteinaceous matrix
surrounded by an intense inflammatory reaction and represent the chronic phase
of gout [2,
7]. Chronic tophaceous gout
usually presents as asymmetric polyarthritis of the feet, hands, wrists,
elbows, and knees. Although tophi are more often periarticular, they may
involve the articular or bursal synovium. Radiographic features of chronic
tophaceous gout are juxtaarticular soft-tissue masses, sharply defined
erosions, and overhanging margins of bone.
Tophi have variable signal intensity on T2-weighted images. A heterogeneous
intermediate to low signal intensity pattern is the most common pattern on
T2-weighted images [2,
7,
8] (Figs.
8A,
8B,
8C and
9A,
9B,
9C,
9D). Calcification of tophi
has been postulated as the cause of the low signal intensity (Figs.
8A,
8B, and
8C). However, because
calcification of tophi is relatively uncommon, signal intensity on T2-weighted
images more often results from the presence of urate crystals and fibrous
tissue (Figs. 9A,
9B,
9C, and
9D).
View larger version (121K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 8A. —Tophaceous gout of elbow in 64-year-old man. Lateral
radiograph shows faintly calcified juxtaarticular mass (asterisk).
Note large erosion with sclerotic border in olecranon process
(arrowheads). Joint space is preserved.
|
|
View larger version (117K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 8B. —Tophaceous gout of elbow in 64-year-old man. Sagittal
T1-weighted image (TR/TE, 410/15) shows lesion of heterogeneous intermediate
to low signal intensity located in olecranon region that also involves triceps
tendon. Erosion of olecranon process (arrowheads) is well seen.
|
|
View larger version (116K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 8C. —Tophaceous gout of elbow in 64-year-old man. Axial
T2-weighted image (2500/90) shows juxta- and intraarticular gouty tophi
deposition (arrows). Lesions show heterogeneous signal intensity,
predominantly intermediate to low. Note associated bone erosions
(arrowheads).
|
|
View larger version (151K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 9A. —Chronic tophaceous gout of ankles in 69-year-old man.
Radiographs (not shown) revealed noncalcified soft-tissue swelling around both
ankles. Coronal T1-weighted image (TR/TE, 550/25) shows tophaceous deposits in
medial aspect of both ankles that erode bilaterally talar margin
(arrowheads). Tophi present as intermediate to low signal intensity.
Note subchondral bone marrow changes with low signal intensity in both
subtalar joints.
|
|
View larger version (113K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 9B. —Chronic tophaceous gout of ankles in 69-year-old man.
Radiographs (not shown) revealed noncalcified soft-tissue swelling around both
ankles. Axial T2-weighted image (2300/90) shows articular and juxtaarticular
bilateral tophi (asterisks) that reveal heterogeneous low signal
intensity. Note associated well-defined bone erosions
(arrowheads).
|
|
View larger version (222K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 9C. —Chronic tophaceous gout of ankles in 69-year-old man.
Radiographs (not shown) revealed noncalcified soft-tissue swelling around both
ankles. Photomicrograph of resected specimen shows large amorphous crystalline
deposits (asterisks), surrounded by fibrous tissue and rimmed by
giant cells and histiocytes. Fibrous tissue and urate crystals may explain low
signal intensity on T2-weighted images. (H and E, x40)
|
|
View larger version (121K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 9D. —Chronic tophaceous gout of ankles in 69-year-old man.
Radiographs (not shown) revealed noncalcified soft-tissue swelling around both
ankles. Photomicrograph of specimen under polarized light shows refractive
urate crystals that form massive conglomerates (asterisks). Note also
needle-shaped isolated urate crystals (arrow). (H and E,
x400)
|
|
Intense gadolinium enhancement of tophi reflects the surrounding
granulation tissue and increased vascularity of the affected synovium.
Heterogeneous peripheral enhancement may also be seen.
Siderotic Synovitis
Siderotic synovitis is seen in cases of chronic hemarthrosis
[9]. Pathologically, the
absence of foam cells and multinucleated giant cells, such as in hemophilic
arthropathy, allows differentiation from pigmented villonodular synovitis. On
MRI, siderotic synovitis appears as a focal or diffuse proliferation of the
synovium, with low signal intensity on both T1- and T2-weighted images and
paramagnetic effect on gradient-echo sequences
[10] (Figs.
10A,
10B, and
10C).
View larger version (113K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 10A. —Focal chronic hemosiderotic synovitis of knee in 45-year-old
woman. Sagittal T2-weighted image (TR/TE, 2500/90) (A) and axial
gradient-recalled echo T2*-weighted image (617/14; flip angle,
30°) (B) show well-defined focal lesion of very low signal
intensity (arrows) in medial patellofemoral recess. Note diffuse
synovial thickening of intermediate to high signal in A
(arrowheads).
|
|
View larger version (132K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 10B. —Focal chronic hemosiderotic synovitis of knee in 45-year-old
woman. Sagittal T2-weighted image (TR/TE, 2500/90) (A) and axial
gradient-recalled echo T2*-weighted image (617/14; flip angle,
30°) (B) show well-defined focal lesion of very low signal
intensity (arrows) in medial patellofemoral recess. Note diffuse
synovial thickening of intermediate to high signal in A
(arrowheads).
|
|
View larger version (162K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 10C. —Focal chronic hemosiderotic synovitis of knee in 45-year-old
woman. Photomicrograph of histologic specimen shows hyperplastic synovial
cells with reddish brown hemosiderin deposition (arrows). (H and E,
x180)
|
|
References
- Weatherall PT. Benign and malignant masses: MR imaging
differentiation. Magn Reson Imag ing Clin N Am1995; 3:669
-694
- Llauger J, Palmer J, Roson N, Bague S, Camins A, Cremades R.
Nonseptic monoarthritis: imaging fea tures with clinical and histopathologic
correlation. RadioGraphics2000; 20[suppl]:S263
-S278[Abstract/Free Full Text]
- Karakida O, Aoki J, Kanno Y, et al. Hemodialy sis-related
arthropathy: a prospective MR study with SE and GRE sequences. Acta
Radiol 1997; 38:158
-164[Medline]
- Kramer J, Recht M, Schweitzer M, et al. MR appear ance of
idiopathic synovial osteochondromatosis. J Comput Assist
Tomogr 1993;17:772
-776[Medline]
- Wittkop B, Davies AM, Mangham DC. Primary synovial chondromatosis
and synovial chondro sarcoma: a pictorial review. Eur
Radiol 2002;12:2112
-2119[Medline]
- Stiskal MA, Neuhold A, Szolar DH, et al. Rheu matoid arthritis of
the craniocervical region by MR imaging: detection and characterization.
AJR 1995;165:585
-592[Abstract/Free Full Text]
- Yu JS, Chung C, Recht M, Dailiana T, Jurdi R. MR Imaging of
tophaceous gout. AJR 1997;168
: 523-528[Abstract/Free Full Text]
- Chen CKH, Yeh LR, Pan HB, et al. Intra-articular gouty tophi of the
knee: CT and MR imaging in 12 patients. Skeletal
Radiol 1999;28:75
-80[Medline]
- O'Connell JX. Pathology of the synovium. Am J Clin
Pathol 2000;114:773
-784[Medline]
- Boles CA, Ward WG Sr. Loose fragments and other debris:
miscellaneous synovial and marrow disorders. Magn Reson Imaging
Clin N Am 2000; 8:371
-390[Medline]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
|
|
 
C.-H. Chang, C.-H. Lu, C.-W. Yu, M.-Z. Wu, C.-Y. Hsu, and T. T.-F. Shih
Tophaceous Gout of the Rotator Cuff. A Case Report
J. Bone Joint Surg. Am.,
January 1, 2008;
90(1):
178 - 182.
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. Libicher and J. Freyschmidt
Dialysis-related amyloidoma presenting as a bilateral gluteal mass.
Am. J. Roentgenol.,
March 1, 2006;
186(3):
907 - 908.
[Full Text]
[PDF]
|
|
|
|
|
|
|
P. J. Sheldon, D. M. Forrester, and T. J. Learch
Imaging of Intraarticular Masses
RadioGraphics,
January 1, 2005;
25(1):
105 - 119.
[Abstract]
[Full Text]
[PDF]
|
|
|
Top
Introduction
Pigmented Villonodular Synovitis
