Differentiating Components of Cerebral Arteriovenous Malformations Using T1-Weighted Gradient Recall Echo MR Imaging

Object Gamma Knife surgery (GKS) has emerged as the treatment of choice for small- to medium-sized cerebral arteriovenous malformations (AVMs) in deep locations. The present study aims to investigate the outcomes of GKS for AVMs in the basal ganglia and thalamus. Methods Between 1989 and 2007, 85 patients with AVMs in the basal ganglia and 97 in the thalamus underwent GKS and were followed up for more than 2 years. The nidus volumes ranged from 0.1 to 29.4 cm3 (mean 3.4 cm3). The mean margin dose at the initial GKS was 21.3 Gy (range 10–28 Gy). Thirty-six patients underwent repeat GKS for residual AVMs at a median 4 years after initial GKS. The mean margin dose at repeat GKS was 21.1 Gy (range 7.5–27 Gy). Results Following a single GKS, total obliteration of the nidus was confirmed on angiograms in 91 patients (50%). In 12 patients (6.6%) a subtotal obliteration was achieved. No flow voids were observed on MR imaging in 14 patients (7.7%). Following single or repeat GKS, total obliteration was angiographically confirmed in 106 patients (58.2%) and subtotal obliteration in 8 patients (4.4%). No flow voids on MR imaging were observed in 18 patients (9.9%). The overall obliteration rates following one or multiple GKSs based on MR imaging or angiography was 68%. A small nidus volume, high margin dose, low number of isocenters, and no history of embolization were significantly associated with an increased rate of obliteration. Twenty-one patients experienced 25 episodes of hemorrhage in 850 risk-years following GKS, yielding an annual hemorrhage rate of 2.9%. Four patients died in this series: 2 due to complications of hemorrhage and 2 due to unrelated diseases. Permanent neurological deficits caused by radiation were noted in 9 patients (4.9%). Conclusions Gamma Knife surgery offers a reasonable chance of obliterating basal ganglia and thalamic AVMs and does so with a low risk of complications. It is an optimal treatment option in patients for whom the anticipated risk of microsurgery is too high.

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Cerebral arteriovenous malformations: flow quantitation by means of two-dimensional cardiac-gated phase-contrast MR imaging.

Radiology ◽

10.1148/radiology.194.3.7862962 ◽

1995 ◽

Vol 194 (3) ◽

pp. 681-686 ◽

Cited By ~ 19

Author(s):

B A Wasserman ◽

W Lin ◽

R W Tarr ◽

E M Haacke ◽

E Müller

Keyword(s):

Mr Imaging ◽

Arteriovenous Malformations ◽

Phase Contrast ◽

Two Dimensional ◽

Cerebral Arteriovenous Malformations

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Staged radiosurgery for extra-large cerebral arteriovenous malformations: method, implementation, and results

Journal of Neurosurgery ◽

10.3171/jns/2008/109/12/s11 ◽

2008 ◽

Vol 109 (Supplement) ◽

pp. 65-72 ◽

Cited By ~ 28

Author(s):

Wen-Yuh Chung ◽

Cheng-Ying Shiau ◽

Hsiu-Mei Wu ◽

Kang-Du Liu ◽

Wan-Yuo Guo ◽

...

Keyword(s):

Mr Imaging ◽

Arteriovenous Malformations ◽

High Signal ◽

Minor Bleeding ◽

Cerebral Arteriovenous Malformations ◽

Presenting Symptoms ◽

Second Stage ◽

The Mean ◽

Cerebral Avms

Object The effectiveness and safety of radiosurgery for small- to medium-sized cerebral arteriovenous malformations (AVMs) have been well established. However, the management for large cerebral AVMs remains a great challenge to neurosurgeons. In the past 5 years the authors performed preplanned staged radiosurgery to treat extra-large cerebral AVMs. Methods An extra-large cerebral AVM is defined as one with nidus volume > 40 ml. The nidus volume of cerebral AVM is measured from the dose plan—that is, as being the volume contained within the best-fit prescription isodose. From January 2003 to December 2007, the authors treated 6 patients with extra-large AVMs by preplanned staged GKS. Staged radiosurgery is implemented by rigid transformation with translation and rotation of coordinates between 2 stages. The average radiation-targeted volume was 60 ml (range 47–72 ml). The presenting symptoms were seizure in 4 patients and a bleeding episode in 2. One patient had undergone a previous craniotomy and evacuation of hematoma. The mean interval between the 2 radiosurgical sessions was 6.9 months (range 4.5–9.1 months). The prescribed marginal dose given to the nidus volume in each stage ranged from 16 to 18.6 Gy. The expected marginal dose of total nidus was 17–19 Gy. Regular follow-up MR imaging was performed every 6 months. The mean follow-up period was 28 months (range 12–54 months). Results Most of the patients exhibited clinical improvement: relief of headache and reduced frequency of seizure attack. All patients had significant regression of nidus observed on MR imaging follow-up. Two patients had angiogram-confirmed complete obliteration of the nidus 45 and 60 months after the second-stage radiosurgical session. One patient experienced minor bleeding 8 months after the second-stage radiosurgery with mild headache. She had satisfactory recovery without clinical neurological deficit after conservative treatment. Conclusions These preliminary results indicate that staged radiosurgery is a practical strategy to treat patients with extra-large cerebral AVMs. It takes longer to obliterate the AVMs. The observed high signal T2 changes after the radiosurgery appeared clinically insignificant in 6 patients followed up for an average of 28 months. Longer follow-up is necessary to confirm its long-term safety.

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Cerebral Arteriovenous Malformations: Comparison of Novel Magnetic Resonance Angiographic Techniques and Conventional Catheter Angiography

Neurosurgery ◽

10.1097/00006123-200105000-00001 ◽

2001 ◽

Vol 48 (5) ◽

pp. 973-983 ◽

Cited By ~ 21

Author(s):

Daniel James Warren ◽

Nigel Hoggard ◽

Lee Walton ◽

Matthias Walter Richard Radatz ◽

Andras A. Kemeny ◽

...

Keyword(s):

Magnetic Resonance ◽

Mr Imaging ◽

Arteriovenous Malformations ◽

Mr Angiography ◽

Three Dimensional ◽

Time Of Flight ◽

Catheter Angiography ◽

Cerebral Arteriovenous Malformations ◽

Gadolinium Chelate ◽

Conventional Catheter Angiography

Abstract OBJECTIVE To investigate the potential of novel magnetic resonance (MR) angiographic techniques for the assessment of cerebral arteriovenous malformations. METHODS Forty patients who were about to undergo stereotactic radiosurgery were prospectively recruited. Three-dimensional, sliding-slab interleaved ky (SLINKY), time-of-flight acquisition was performed, as was a dynamic MR digital subtraction angiography (DSA) procedure in which single thick slices (6–10 cm) were obtained using a radiofrequency spoiled Fourier-acquired steady-state sequence (1 image/s). Sixty images were acquired, in two or three projections, during passage of a 6- to 10-ml bolus of gadolinium chelate. Subtraction and postprocessing were performed, and images were viewed in an inverted cine mode. SLINKY time-of-flight acquisition was repeated after the administration of gadolinium. Routine stereotactic conventional catheter angiography was performed after MR imaging. All images were assessed (in a blinded randomized manner) for Spetzler-Martin grading and determination of associated vascular pathological features. RESULTS Forty-one arteriovenous malformations were assessed in 40 patients. Contrast-enhanced (CE) SLINKY MR angiography was the most consistent MR imaging technique, yielding a 95% correlation with the Spetzler-Martin classification defined by conventional catheter angiography; MR DSA exhibited 90% agreement, and SLINKY MR angiography exhibited 81% agreement. CE SLINKY MR angiography provided improved nidus delineation, compared with non-CE SLINKY MR angiography. Dynamic information from MR DSA significantly improved the observation of early-draining veins and associated aneurysms. CONCLUSION CE SLINKY MR angiographic assessment of cerebral arteriovenous malformations offers significant advantages, compared with the use of non-CE SLINKY MR angiography, including improved nidus demonstration. MR DSA shows promise as a noninvasive method for dynamic angiography but is presently restricted by limitations in both temporal and spatial resolution.

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Gamma knife surgery of cerebral arteriovenous malformations: Serial mr imaging studies after radiosurgery

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/0360-3016(93)90354-x ◽

1993 ◽

Vol 25 (2) ◽

pp. 315-323 ◽

Cited By ~ 42

Author(s):

Wan-Yuo Guo ◽

Christer Lindquist ◽

Bengt Karlsson ◽

Lars Kihlström ◽

Ladislau Steiner

Keyword(s):

Mr Imaging ◽

Gamma Knife ◽

Arteriovenous Malformations ◽

Gamma Knife Surgery ◽

Cerebral Arteriovenous Malformations ◽

Imaging Studies

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Slowly Enhancing Lesions after Gamma Knife Radiosurgery for Cerebral Arteriovenous Malformations

Rivista di Neuroradiologia ◽

10.1177/197140090201500611 ◽

2002 ◽

Vol 15 (6) ◽

pp. 737-743

Author(s):

H. Mori ◽

S. Aoki ◽

M. Shin ◽

M. Tago ◽

T. Masumoto ◽

...

Keyword(s):

Mr Imaging ◽

Gamma Knife ◽

Arteriovenous Malformations ◽

Gamma Knife Radiosurgery ◽

Mr Images ◽

Cerebral Arteriovenous Malformations ◽

Imaging Appearance ◽

Dynamic Mr Imaging ◽

Contrast Enhanced ◽

Dynamic Mr

We present the contrast-enhanced dynamic MR imaging appearance of cerebral arteriovenous malformations (AVM) following gamma knife radiosurgery and discuss the implications of this finding with respect to treatment. Dynamic MR images obtained in our three AVM patients following radiosurgery revealed slowly enhancing lesions. This pattern is not observed in all cases involving AVMs following gamma knife radiosurgery. When it is present, a haemangioma-like lesion should be considered.

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