Development and testing of a radiosurgery-based arteriovenous malformation grading system.
Authors: Pollock BE
Abstract
Stereotactic radiosurgery is an accepted management option for many patients with intracranial arteriovenous malformations (AVMs). The Spetzler-Martin grading scale is the most widely accepted and utilized method to predict outcomes after surgical resection of intracranial AVMs but is not sensitive to factors that correlate with successful AVM radiosurgery. The need for a system that accurately predicts patient outcomes after AVM radiosurgery led to the development of the radiosurgery-based AVM score (RBAS). The RBAS has evolved and has been modified over the years to reflect c...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Radiosurgery for brainstem arteriovenous malformation.
Authors: Maruyama K, Koga T, Niranjan A, Kondziolka D, Flickinger JC, Lunsford LD
Abstract
The authors outlined the treatment result of arteriovenous malformations (AVMs) inside the brainstem by reviewing the 4 existing studies in detail. The majority of patients with brainstem AVMs had a history of hemorrhage, leading to neurological deficits at the time of treatment in 72-73% of patients. The most frequent location was the midbrain or the pons depending on studies, while the medulla oblongata was the least common location throughout the series. The obliteration rate after radiosurgery was 44-73%, which w...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Multistaged volumetric management of large arteriovenous malformations.
Authors: Kano H, Kondziolka D, Flickinger JC, Park KJ, Parry PV, Yang HC, Sirin S, Niranjan A, Novotny J, Lunsford LD
Abstract
We sought to define the long-term outcomes and risks of arteriovenous malformation (AVM) management using 2 or more stages of stereotactic radiosurgery (SRS) for symptomatic large-volume AVMs unsuitable for surgery. Two decades ago, we prospectively began to stage anatomical components in order to deliver higher single doses to AVMs>10 cm3 in volume. Forty-seven patients with large AVMs underwent volume-staged SRS. The median interval between the two SRS procedures was 4.9 month...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Endovascular embolization in combination with radiosurgery for treatment of arteriovenous malformations.
Authors: Miller RA, Jankowitz B
Abstract
There are several options for the treatment of patients with arteriovenous malformations (AVMs). Surgical resection, radiosurgery and endovascular embolization can be used alone or in conjunction. In patients with AVMs not amenable to surgical resection due to large size or location, radiosurgery can address some but not all of these issues as cure rates remain low for volumes>10 cm3. Combining endovascular embolization with stereotactic radiosurgery allows potential volume reduction and reduction of risks related to factors that may increase bleeding risks durin...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Stereotactic radiosurgery after embolization for arteriovenous malformations.
Authors: Kano H, Kondziolka D, Flickinger JC, Park KJ, Iyer A, Yang HC, Liu X, Monaco EA, Niranjan A, Lunsford LD
Abstract
We sought to define the long-term benefits and risks of stereotactic radiosurgery (SRS) for arteriovenous malformation (AVM) patients who underwent prior embolization. Between 1987 and 2006, we performed Gamma Knife® SRS on 120 patients with AVM who underwent embolization followed by SRS. Sixty-four patients (53%) had at least 1 prior hemorrhage. The median number of embolizations varied from 1 to 5. The median target volume was 6.6 cm3 (range, 0.2-26.3 cm3). The median margin dose wa...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Long-term side effects of radiosurgery for arteriovenous malformations.
In this report, our experiences with 181 consecutive patients who underwent Gamma Knife radiosurgery (GKRS) for arteriovenous malformations (AVMs) during an approximately quarter century period from 1978 to 2002 will be summarized along with much of what we have learned from a wealth of already published data. During the mean post-GKRS follow-up period of 10.2 years (range, 5.4-30.6), 15 (8.3%) of our 181 patients experienced stereotactic radiosurgery-related, symptomatic complications. Among these 15 patients, 12 manifested complications 5 years or more after GKRS. Furthermore, in 5 of these 12, the complications were see...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Management of adverse radiation effects after radiosurgery for arteriovenous malformations.
Authors: Monaco EA, Niranjan A, Kano H, Flickinger JC, Kondziolka D, Lunsford LD
Abstract
Over the last two decades, stereotactic radiosurgery (SRS) has become a mainstay in the management of arteriovenous malformations (AVMs) of the brain. An extensive collective experience has demonstrated that SRS is a minimally invasive technique that can produce excellent AVM obliteration rates with only a modest risk of permanent adverse radiation effects (AREs). Controversy remains regarding the optimal treatment approach for AVMs, with much of the debate centered upon the risk:benefit ratios of microsurgical resect...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Morphological observations in brain arteriovenous malformations after gamma knife radiosurgery.
Authors: Szeifert GT, Levivier M, Lorenzoni J, Nyáry I, Major O, Kemeny AA
Abstract
Morphological studies after Gamma Knife radiosurgery (GKRS) revealed endothelial destruction followed by spindle-shaped cell proliferation in the subendothelial region and in the connective tissue stroma of arteriovenous malformation (AVM) vessels. Histological, immunohistochemical and ultrastructural characteristics of this spindle-shaped cell population in the irradiated AVMs were reminiscent of those described as myofibroblasts in wound healing processes and pathological fibromatoses. These modified fibroblasts have con...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Stereotactic radiosurgery guideline for the management of patients with intracranial arteriovenous malformations.
Authors: Niranjan A, Lunsford LD
Abstract
Our objective was to provide guidelines about the use of stereotactic radiosurgery in symptomatic patients with imaging-identified arteriovenous malformations (AVMs) of the brain. We reviewed evidence-based medicine and clinical experience with radiosurgery for AVM of the brain to develop guidelines and provide scientific foundation for patients and physicians. Major recommendations include the definition of AVM patients suitable for various management strategies ranging from observation to surgical excision to endovascular embolization and stereotactic radiosurger...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Cavernous malformations and hemorrhage risk.
Authors: Kondziolka D, Monaco EA, Lunsford LD
Abstract
Widespread availability of magnetic resonance imaging has helped our understanding of the natural history of cavernous malformations (CMs) of the brain. CMs present with diverse clinical manifestations. Supratentorial CMs are often identified incidentally. The clinical presentation corresponds with lesion location. Symptomatic, hemorrhagic CMs of the brainstem pose a challenging clinical problem as they are often associated with high surgical morbidity. In order to study the natural history of CM, we performed a prospective analysis on a series of pati...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Radiosurgery of brain cavernomas--long-term results.
Authors: Liscak R
Abstract
The radiosurgery of cavernomas remains a controversial issue. The only way to verify the positive effect of the treatment is by clinical observation during a longer follow-up period, where a decreased annual risk of rebleeding should be observed after the latent interval inherent to radiosurgery. Besides this, an improvement in clinical symptoms (e.g. secondary epilepsy) and regression of the treated lesion might also be observed. In a group of 112 patients with brain cavernomas treated in our centre between 1992 and 2000 with the marginal dose of a median 16 Gy, the risk of blee...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Radiosurgical treatment for epilepsy associated with cavernomas.
Authors: Lévêque M, Carron R, Bartolomei F, Régis J
Abstract
Cavernous malformations (CMs) are congenital vascular malformations of the brain, which often present with drug-resistant epilepsy. Microsurgical excision remains the preferred approach for cortical-subcortical epileptogenic CMs that are not located in functional cortex. For patients presenting with seizures arising from eloquent cortex surrounding the lesion, radiosurgery appears to be a suitable alternative. We evaluated the effectiveness of Gamma Knife (GK) surgery in the management of drug-resistant seizures associated with CMs in a retros...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Stereotactic radiosurgery guidelines for the management of patients with intracranial cavernous malformations.
In this report, we provide guidelines about the use of stereotactic radiosurgery in CM patients who had 2 documented symptomatic hemorrhages. We reviewed the evidence-based medicine and clinical experience with radiosurgery for CM of the brain and developed guidelines and provided a scientific foundation for patients and physicians. We also reviewed the controversy surrounding CM radiosurgery and discussed its origin and validity. Our recommendations include the selection of CM patients suitable for various management strategies ranging from observation to surgical excision and stereotactic radiosurgery. Radiosurgery is an...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Intracranial dural arteriovenous fistulas: natural history and rationale for treatment with stereotactic radiosurgery.
We present an update on 321 DAVF patients treated at the Taipei Veterans General Hospital using Gamma Knife radiosurgery. The prescribed mean margin dose was 17.2 Gy. In our series, 98% of patients had a stable or improved clinical condition after radiosurgery. Stereotactic radiosurgery using the Gamma Knife is a safe and effective alternative for the treatment of DAVFs.
PMID: 23258522 [PubMed - indexed for MEDLINE] (Source: Progress in Neurological Surgery)
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
Stereotactic radiosurgery with or without embolization for intracranial dural arteriovenous fistulas.
Authors: Yang H, Kano H, Kondziolka D, Niranjan A, Flickinger JC, Horowitz MB, Lunsford LD
Abstract
Treatment options for symptomatic dural arteriovenous fistulas (DAVFs) include surgery, embolization and stereotactic radiosurgery (SRS). We reviewed our DAVF experience at the University of Pittsburgh and assessed the role of SRS. We evaluated 40 consecutive patients who underwent Gamma Knife SRS for 44 DAVFs. Twenty-eight patients had upfront SRS before or after embolization performed at our institution, and 12 patients underwent delayed SRS for recurrent or residual DAVFs after initial embolization. The m...
Source: Progress in Neurological Surgery - November 20, 2015 Category: Neurosurgery Tags: Prog Neurol Surg Source Type: research
