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A man in his late thirties developed hematospermia and underwent an MRI. Initial treatment gave relief; blood came back 18 months later. A 5 cm pelvic soft tissue mass was resected.
A man in his late thirties developed hematospermia and underwent an MRI. Initial treatment gave relief; blood came back 18 months later. A 5 cm pelvic soft tissue mass was resected.
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What is the lesion?
How was it treated?
What is the lesion?
How was it treated?
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Diagnosis: arteriovenous malformation (AVM), with organization and ossification of embolic material
Treatment: endovascular embolization with Onyx 34
Diagnosis: arteriovenous malformation (AVM), with organization and ossification of embolic material
Treatment: endovascular embolization with Onyx 34
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Pelvic AVMs occur in both sexes and can result in hematospermia or vaginal bleeding.
Although they may extend to involve the uterus, they should be distinguished from uterine AVMs, in which the arteriovenous communications exist entirely within the uterus.
Pelvic AVMs occur in both sexes and can result in hematospermia or vaginal bleeding.
Although they may extend to involve the uterus, they should be distinguished from uterine AVMs, in which the arteriovenous communications exist entirely within the uterus.
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Acquired AVMs limited to the uterus:
•May follow instrumentation, c-section, or uterine malignancies
•Are often less complex and are probably better regarded as fistulas
•May result in life-threatening bleeding
Acquired AVMs limited to the uterus:
•May follow instrumentation, c-section, or uterine malignancies
•Are often less complex and are probably better regarded as fistulas
•May result in life-threatening bleeding
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Like CNS AVMs and uterine leiomyomas, pelvic soft tissue and uterine AVMs can be treated with embolization.
The material shown here is called Onyx 34 (Micro Therapeutics, Inc). [Note: no author COI!]
Like CNS AVMs and uterine leiomyomas, pelvic soft tissue and uterine AVMs can be treated with embolization.
The material shown here is called Onyx 34 (Micro Therapeutics, Inc). [Note: no author COI!]
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It’s a mixture of ethylene-vinyl alcohol copolymer (EVOH) and tantalum dissolved in dimethylsulfoxide (DMSO).
It’s a mixture of ethylene-vinyl alcohol copolymer (EVOH) and tantalum dissolved in dimethylsulfoxide (DMSO).
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Crazy, right? Basically, metal shavings and plastic mixed in an angiotoxic diluent.
periodictable.com/Elements/073/i…
Crazy, right? Basically, metal shavings and plastic mixed in an angiotoxic diluent.
periodictable.com/Elements/073/i…
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Nice animation of vessel filling shown here at 5:00 minutes in:
Nice animation of vessel filling shown here at 5:00 minutes in:
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“Often compared to how lava flows, Onyx begins to solidify from the outside, while the inner core remains liquid for a given duration.”
“Often compared to how lava flows, Onyx begins to solidify from the outside, while the inner core remains liquid for a given duration.”
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This seems to be reflected histologically in resected specimens, in which recanalization (repermeation) follows the innermost part of the embolized material.
This seems to be reflected histologically in resected specimens, in which recanalization (repermeation) follows the innermost part of the embolized material.
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Filling of the vessel has to occur slowly, as DMSO can cause angionecrosis.
Jahan et al.: PMID:11334300
Filling of the vessel has to occur slowly, as DMSO can cause angionecrosis.
Jahan et al.: PMID:11334300
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If filling is successful, the risk of bleeding goes down.
Repermeation can occur after about 3 months in up to 50% of cases, but its clinical significance varies.
Gruber et al.: PMID: 8871719
If filling is successful, the risk of bleeding goes down.
Repermeation can occur after about 3 months in up to 50% of cases, but its clinical significance varies.
Gruber et al.: PMID: 8871719
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Another nice example of Onyx histology can be found in @yro854 's Atlas of Medical Foreign Bodies:
flickr.com/photos/foreign…
Another nice example of Onyx histology can be found in @yro854 's Atlas of Medical Foreign Bodies:
flickr.com/photos/foreign…
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To sum up the histologic findings:
•The translucent, eosinophilic material = EVOH
•the black granular pigment = tantalum particles, which make it radiopaque
•EVOH looks pretty similar to polyvinyl alcohol (PVA), which shows a similar giant cell reaction
[fin]
To sum up the histologic findings:
•The translucent, eosinophilic material = EVOH
•the black granular pigment = tantalum particles, which make it radiopaque
•EVOH looks pretty similar to polyvinyl alcohol (PVA), which shows a similar giant cell reaction
[fin]
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