Stereotactic radiosurgery for arteriovenous malformations of the brain

1991 ◽  
Vol 75 (4) ◽  
pp. 512-524 ◽  
Author(s):  
L. Dade Lunsford ◽  
Douglas Kondziolka ◽  
John C. Flickinger ◽  
David J. Bissonette ◽  
Charles A. Jungreis ◽  
...  

✓ Stereotactic radiosurgery successfully obliterates carefully selected arteriovenous malformations (AVM's) of the brain. In an initial 3-year experience using the 201-source cobalt-60 gamma knife at the University of Pittsburgh, 227 patients with AVM's were treated. Symptoms at presentation included prior hemorrhage in 143 patients (63%), headache in 104 (46%), and seizures in 70 (31%). Neurological deficits were present in 102 patients (45%). Prior surgical resection (resulting in subtotal removal) had been performed in 36 patients (16%). In 47 selected patients (21%), embolization procedures were performed in an attempt to reduce the AVM size prior to radiosurgery. The lesions were classified according to the Spetzler grading system: 64 (28%) were Grade VI (inoperable), 22 (10%) were Grade IV, 90 (40%) were Grade III, 43 (19%) were Grade II, and eight (4%) were Grade I. With the aid of computer imaging-integrated isodose plans for single-treatment irradiation, total coverage of the AVM nidus was possible in 216 patients (95%). The location and volume of the AVM were the most important factors for the selection of radiation dose. Magnetic resonance (MR) imaging was performed at 6-month intervals in 161 patients. Seventeen patients who had MR evidence of complete obliteration underwent angiography within 3 months of imaging: in 14 (82%) complete obliteration was confirmed. Complete angiographic obliteration was confirmed in 37 (80%) of 46 patients at 2 years, the earliest confirmation being 4 months (mean 17 months) after radiosurgery. The 2-year obliteration rates according to volume were: all eight (100%) AVM's less than 1 cu cm; 22 (85%) of 26 AVM's of 1 to 4 cu cm; and seven (58%) of 12 AVM's greater than 4 cu cm. Magnetic resonance imaging revealed postirradiation changes in 38 (24%) of 161 patients at a mean interval of 10.2 months after radiosurgery; only 10 (26%) of those 38 patients were symptomatic. In the entire series, two patients developed permanent new neurological deficits believed to be treatment-related. Two patients died of repeat hemorrhage at 6 and 23 months after treatment during the latency interval prior to obliteration. Stereotactic radiosurgery is an important method to obliterate AVM's, especially those previously considered inoperable. Success and complication risks are related to the AVM location and the volume treated.

1991 ◽  
Vol 75 (1) ◽  
pp. 40-44 ◽  
Author(s):  
Michael B. Sisti ◽  
Robert A. Solomon ◽  
Bennett M. Stein

✓ Surgical resection of 10 obscure arteriovenous malformations (AVM's) was accomplished with craniotomy guided by computerized tomography (CT) or angiography and the use of the Brown-Roberts-Wells stereotactic frame. Stereotactic craniotomy was invaluable for resection of the following types of AVM's: 1) AVM's with a nidus less than 2 cm in diameter, 2) AVM's located in an eloquent area of the brain, and 3) AVM's located deep in the brain. Stereotactic localization of these AVM's on preoperative radiological studies provides a precise route to the nidus, often avoiding important areas of the brain. This series included six male and four female patients with a mean age of 32 years. All patients presented with an intracerebral hemorrhage, from which eight made a complete neurological recovery prior to surgery. Two AVM's were located on the cortex, three were found subcortically, and five were situated near the ventricles or in the deep white matter. As a guide, angiography was used in six cases and CT in four cases. In each instance, the study providing the best image of the AVM nidus was employed. Postoperatively, no neurological deficits were found in eight patients and, in the two patients with preoperative deficits, neurological improvement was observed after recovery from surgery. Postoperative studies revealed complete removal of the AVM in all patients, and all lesions were confirmed histologically. The authors conclude that stereotactic craniotomy provides the optimum operative approach for the localization and microsurgical resection of AVM's that are either obscure or located deep in the brain.


1996 ◽  
Vol 84 (3) ◽  
pp. 437-441 ◽  
Author(s):  
Bruce E. Pollock ◽  
L. Dade Lunsford ◽  
Douglas Kondziolka ◽  
David J. Bissonette ◽  
John C. Flickinger

✓ Arteriovenous malformations (AVMs) that are located within the postgeniculate optic radiations or striate cortex are difficult to resect without creating postoperative visual defects. To reduce the risk of an AVM hemorrhage and to enhance the possibility of preserving visual function, the authors performed stereotactic radiosurgery in 34 patients with newly diagnosed or residual AVMs of the visual pathways. The mean AVM volume was 4.7 ml, and the average radiation dose to the AVM margin was 21 Gy. The median follow up was 47 months (range 16–83 months). Two (6%) of 34 patients had documented new visual field defects (central scotoma in one, and partial hemianopsia in one) after single-stage radiosurgery, but no patient developed a new permanent homonymous hemianopsia. Angiography was performed in all patients at a median of 26 months after radiosurgery: 22 (65%) had complete obliteration, 10 (29%) had a significant decrease in AVM volume, one (3%) had only a persistent early draining vein without residual nidus, and one (3%) had no change in the AVM. Thirteen (81%) of 16 patients with AVMs less of than 4 ml had complete obliteration. Five patients had second-stage stereotactic radiosurgery after angiography revealed a persistent AVM nidus; two patients eligible for follow-up angiography had complete obliteration, thereby increasing the overall series obliteration rate to 71%. The calculated annual risk of AVM bleeding (before radiographic evidence of obliteration) was 2.4%. No patient bled after angiographically confirmed obliteration. In most patients stereotactic radiosurgery obliterates visual pathway AVMs and also preserves preoperative visual function. Multimodality management (embolization, microsurgery, or staged radiosurgery) enhances AVM obliteration and visual preservation rates.


2000 ◽  
Vol 93 (6) ◽  
pp. 987-991 ◽  
Author(s):  
Bruce E. Pollock ◽  
Yolanda I. Garces ◽  
Scott L. Stafford ◽  
Robert L. Foote ◽  
Paula J. Schomberg ◽  
...  

Object. The use of stereotactic radiosurgery to treat cerebral cavernous malformations (CMs) is controversial. To evaluate the efficacy and safety of CM radiosurgery, the authors reviewed the experience at the Mayo Clinic during the past 10 years.Methods. Seventeen patients underwent radiosurgery for high-surgical-risk CMs in the following sites: thalamus/basal ganglia (four patients), brainstem (12 patients), and corpus callosum (one patient). All patients had experienced at least two documented hemorrhages before undergoing radiosurgery. Stereotactic magnetic resonance (MR) imaging was used for target localization in all cases. The median margin radiation dose was 18 Gy and the median maximum dose was 32 Gy. The median length of follow-up review following radiosurgery was 51 months.The annual hemorrhage rate during the 51 months preceding radiosurgery was 40.1%, compared with 8.8% in the first 2 years following radiosurgery and 2.9% thereafter. In 10 patients (59%) new neurological deficits developed that were associated with regions of increased signal on long—repetition time MR imaging performed a median of 8 months (range 5–16 months) after radiosurgery. Three patients recovered, giving the group a permanent radiation-related morbidity rate of 41%. Compared with 31 patients harboring arteriovenous malformations (AVMs) of sizes and in locations similar to those of the aforementioned CMs, who underwent radiosurgery during the same time period, the patients with CMs were more likely to experience radiation-related complications (any complication, 59% compared with 10%; p < 0.001; permanent complication, 41% compared with 10%; p = 0.02).Conclusions. It is impossible to conclude that radiosurgery protects patients with CMs against future hemorrhage risk based on the available data, although it appears that some reduction in the bleeding rate occurs after a latency interval of several years. The risk of radiation-related complications after radiosurgery to treat CMs is greater than that found after radiosurgery in AVMs, even when adjusting for lesion size and location and for radiation dose.


1999 ◽  
Vol 90 (4) ◽  
pp. 695-701 ◽  
Author(s):  
Michael K. Morgan ◽  
Lali H. S. Sekhon ◽  
Simon Finfer ◽  
Verity Grinnell

Object. The aim of this study was to analyze delayed neurological deficits following surgical resection of arteriovenous malformations (AVMs).Methods. The authors report on a consecutive series of 200 patients with angiographically proven AVMs of the brain that were surgically resected between January 1989 and June 1998. The 30-day mortality rate for patients in this series was 1%, with one death caused by AVM resection and one death attributed to basilar artery aneurysm repair following successful AVM resection. The Spetzler—Martin grading system correlated well with the difficulty of surgery. No permanent incidence of morbidity resulted from resection of Grade I or II AVMs; the percentage of patients with a significant neurological deficit due to resection was 7.8% for those with Grade III lesions and 33.3% for those with Grade IV or V AVMs. However, this grading system did not accurately predict the development of delayed neurological deficits.Ten patients (5%) developed delayed neurological deficits after recovering from anesthesia and surgery. The delayed deficit was due to hemorrhage in four of the 10 patients and all four had undergone resection of AVMs measuring at least 4 cm in diameter. An increase in blood pressure during the first 8 postoperative days precipitated hemorrhage in these patients. Edema arising as a consequence of propagated venous thrombosis (two patients) was associated with extensive venous drainage networks rather than large AVM niduses. Both hemorrhagic and edematous complications can be included under the umbrella term of “arterial-capillary-venous hypertensive syndrome” to describe the common underlying pathogenesis accurately. An additional four patients developed a delayed deficit as a result of vasospasm. Vasospasm occurred when resection had involved extensive dissection of proximal anterior and middle cerebral arteries; in such cases the incidence of vasospasm was 27%.Conclusions. On the basis of their analysis of these complications, the authors recommend strict blood pressure control for patients with lesions measuring 4 cm or more in diameter (particularly those with a deep arterial supply). Thromboprophylaxis with aspirin and heparin is prescribed for patients with extensive venous drainage networks, and prophylactic nimodipine therapy and angiographic surveillance for vasospasm are suggested for patients in whom extensive dissection of proximal anterior or middle cerebral arteries has been necessary.


1986 ◽  
Vol 64 (6) ◽  
pp. 857-864 ◽  
Author(s):  
Robert A. Solomon ◽  
Bennett M. Stein

✓ In a series of 250 intracranial arteriovenous malformations (AVM's), 12 malformations involved the brain stem. Nine of these lesions were treated surgically, with complete obliteration in eight. There were no operative deaths, and only two patients were made worse by surgery. In the nonsurgically treated group, one patient had embolization therapy and two patients underwent radiation therapy. Results in these three patients have not been satisfactory. These data indicate that brain-stem AVM's can be surgically removed with acceptable morbidity.


1995 ◽  
Vol 82 (2) ◽  
pp. 190-195 ◽  
Author(s):  
Robert W. Hurst ◽  
Alex Berenstein ◽  
Mark J. Kupersmith ◽  
Mary Madrid ◽  
Eugene S. Flamm

✓ Cerebral deep central arteriovenous malformations (AVMs) are uncommon lesions associated with considerable difficulty in treatment. The authors report a series of 14 deep central AVMs treated by endovascular methods and examine the present role of endovascular treatment. This treatment used alone resulted in complete obliteration of AVMs in approximately 15% of cases and reduction in 50% to a size permitting treatment by means of radiosurgery. Reversal of previous neurological signs and symptoms occurred in 35.7% of embolized patients. Overall, nearly 80% of patients had either complete obliteration of the lesion, reduction to a size allowing radiosurgical treatment, or reversal of previous neurological deficits. There were treatment complications in 14.3% of the cases. Endovascular treatment methods may make a significant contribution to the therapy of AVMs that have a particularly poor course and are difficult to treat by other means.


1995 ◽  
Vol 83 (5) ◽  
pp. 832-837 ◽  
Author(s):  
Yoshihiro Yamamoto ◽  
Robert J. Coffey ◽  
Douglas A. Nichols ◽  
Edward G. Shaw

✓ During the authors' initial 4-year experience with radiosurgery using the Leksell cobalt-60 gamma unit, they treated 121 patients with cerebral arteriovenous malformations (AVMs). The radiosurgical dose to the margin of the nidus was 20 Gy for lesions less than 2.0 cm in diameter (volume ≤ 4.2 cm3); 18 Gy for malformations 2.1 to 3.0 cm in diameter (volume 4.2–14.1 cm3); and 16 Gy for malformations greater than 3.0 cm (volume > 14.1 cm3). Fifty-one patients underwent follow-up angiography between 1 and 3 years after treatment, and complete obliteration of the nidus was confirmed in 38 (74.5%) of these patients. Thirty-two (74.4%) of 43 AVMs with volumes of 10 cm3 or less and six (75%) of eight larger AVMs (volume 11–30 cm3) showed complete obliteration. Analysis of the time course of AVM nidus shrinkage and obliteration showed that most of the radiosurgically induced effect had occurred by 36 months after treatment. Retrospective analysis of the dose plans for 10 AVMs that were not obliterated by 36 months after gamma knife radiosurgery at the authors' institution (eight cases) or elsewhere (two cases) revealed that six AVMs had not been covered completely by the prescribed isodose. Six (5%) of the 121 patients developed neurological deficits as a direct result of radiosurgical treatment. The authors infer from these data that malformations up to 30 cm3 in volume (approximately 4.0 cm in average diameter) can be treated effectively with an acceptably low complication rate using a radiosurgical dose of 16 Gy to the margin of the nidus. The obliteration rate for the larger malformations that were treated with a dose of 16 to 18 Gy appears to be similar to that for smaller ones treated with 18 to 20 Gy. As more experience accrues using radiosurgery to treat AVMs, patient selection criteria and the variables associated with successful obliteration of the nidus should become more clearly defined.


1975 ◽  
Vol 43 (6) ◽  
pp. 661-670 ◽  
Author(s):  
Charles G. Drake

✓ The author reports his surgical experience with five cases of arteriovenous malformation of the brain stem and cerebellopontine angle causing multiple hemorrhages and severe neurological deficits. Surgical removal of the lesions had good results in four cases; there was one death.


2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 113-119 ◽  
Author(s):  
D. Hung-Chi Pan ◽  
Wan-Yuo Guo ◽  
Wen-Yuh Chung ◽  
Cheng-Ying Shiau ◽  
Yue-Cune Chang ◽  
...  

Object. A consecutive series of 240 patients with arteriovenous malformations (AVMs) treated by gamma knife radiosurgery (GKS) between March 1993 and March 1999 was evaluated to assess the efficacy and safety of radiosurgery for cerebral AVMs larger than 10 cm3 in volume. Methods. Seventy-six patients (32%) had AVM nidus volumes of more than 10 cm3. During radiosurgery, targeting and delineation of AVM nidi were based on integrated stereotactic magnetic resonance (MR) imaging and x-ray angiography. The radiation treatment was performed using multiple small isocenters to improve conformity of the treatment volume. The mean dose inside the nidus was kept between 20 Gy and 24 Gy. The margin dose ranged between 15 to 18 Gy placed at the 55 to 60% isodose centers. Follow up ranged from 12 to 73 months. There was complete obliteration in 24 patients with an AVM volume of more than 10 cm3 and in 91 patients with an AVM volume of less than 10 cm3. The latency for complete obliteration in larger-volume AVMs was significantly longer. In Kaplan—Meier analysis, the complete obliteration rate in 40 months was 77% in AVMs with volumes between 10 to 15 cm3, as compared with 25% for AVMs with a volume of more than 15 cm3. In the latter, the obliteration rate had increased to 58% at 50 months. The follow-up MR images revealed that large-volume AVMs had higher incidences of postradiosurgical edema, petechiae, and hemorrhage. The bleeding rate before cure was 9.2% (seven of 76) for AVMs with a volume exceeding 10 cm3, and 1.8% (three of 164) for AVMs with a volume less than 10 cm3. Although focal edema was more frequently found in large AVMs, most of the cases were reversible. Permanent neurological complications were found in 3.9% (three of 76) of the patients with an AVM volume of more than 10 cm3, 3.8% (three of 80) of those with AVM volume of 3 to 10 cm3, and 2.4% (two of 84) of those with an AVM volume less than 3 cm3. These differences in complications rate were not significant. Conclusions. Recent improvement of radiosurgery in conjunction with stereotactic MR targeting and multiplanar dose planning has permitted the treatment of larger AVMs. It is suggested that gamma knife radiosurgery is effective for treating AVMs as large as 30 cm3 in volume with an acceptable risk.


1977 ◽  
Vol 47 (1) ◽  
pp. 50-56 ◽  
Author(s):  
Hiroshi Matsumura ◽  
Yasumasa Makita ◽  
Kuniyuki Someda ◽  
Akinori Kondo

✓ We have operated on 12 of 14 cases of arteriovenous malformation (AVM) in the posterior fossa since 1968, with one death. The lesions were in the cerebellum in 10 cases (three anteromedial, one central, three lateral, and three posteromedial), and in the cerebellopontine angle in two; in two cases the lesions were directly related to the brain stem. The AVM's in the anterior part of the cerebellum were operated on through a transtentorial occipital approach.


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