Transcript Radiology Case Presentation

Radiology Case Presentation
David R. Beckert, MS-4
11/8/05
Case Background
• Clinical History: 22 y.o. female presented
to Neuro angio for imaging of AVM, which
was discovered at OSH, in order to
proceed to interventional radiology for
gamma knife ablation procedure.
•
(Note: Unclear as to her original complaint that lead to the discovery of the AVM at the OSH)
Radiographic Images
Medium-sized AVM
•
•
Blood flow to AVM from internal carotid and vertebral
Distal venous stricture also noted
Arteriovenous malformations
• Intracranial AVMs = 0.1% prevalence
(aneurysms =1.0%).
• Supratentorial lesions = 90%
• Posterior fossa = 10%
• AVMs account for:
– 1 to 2 % of all strokes
– 3 % of strokes in young adults
– 9 % of subarachnoid hemorrhages
AVM Clinical Summary
• AVMs usually present in the second to the
fourth decade of life.
• Presentation:
– Intracranial hemorrhage = 41-79 %
– Seizures = 11-33 %
– Headaches or progressive deficit
– Younger patients (<30 yo) most often present
with seizures, while older patients more
commonly present with hemorrhage
AVM Imaging
• Angiography is the gold standard for the diagnosis,
treatment planning, and follow-up after treatment
• Anatomical and physiological information such as the
nidus configuration, its relationship to surrounding
vessels, and localization of the draining or efferent
portion of the AVM are readily obtained
• Contrast transit times provide additional useful
information regarding the flow state of the lesion; this is
critical for endovascular treatment planning
• AVMs typically first discovered via MRI/CT
• MRI- very sensitive for location purposes and following
pts after treatment
AVM Grading Scale
AVM Treatment
• Pt. Age is most important factor
• Options include surgery, stereotactic radiosurgery, and endovascular
embolization
• Stereotactic radiosurgery — Stereotactically focused high energy
beams of photons or protons to a defined volume containing the
AVM nidus induces progressive thrombosis.
• Time course usually one to three years, and the time between
treatment and obliteration is referred to as the latency period.
• Once the lesion is completely obliterated, the hemorrhage risk from
the AVM is very low
• Successful AVM obliteration with radiosurgery depends upon lesion
size and dose of radiation (complications also depend on
location/size of AVM and volume treated)
References
• Singer, RJ, Ogilvy, CS, Rordorf, G.
Cerebral arteriovenous malformations.
UpToDate Online 13.3. February 25,
2005.
• Spetzler, RF, Martin, NA. A proposed
grading system for arteriovenous
malformations. J Neurosurg 1986; 65:476.