Factors Determining the Clinical Complications of Radiosurgery for AVM

Reporting of angiographic studies in patients diagnosed with a cerebral arteriovenous malformation: a systematic review

A cerebral arteriovenous malformation (cAVM) is an abnormal tangle of cerebral blood vessels. The consensus document by the Joint Writing Group (JWG) highlighted which cAVM features should be recorded. Subsequent publications have reported cAVM angioarchitecture, but it is unknown if all followed the JWG recommendations. The aim of this systematic review was to describe use of the JWG guidelines. A database search, using the PRISMA checklist, was performed. We describe the proportion of publications that used JWG reporting standards, which standards were used, whether the definitions used differed from the JWG, or if any additional angiographic features were reported. Out of 4306 articles identified, 105 were selected, and a further 114 from other sources. Thirty-three studies (33/219; 15%) specifically referred to using JWG standards. Since the JWG publication, few studies have used their standards to report cAVMs. This implies that the angioarchitecture of cAVMs are not routinely fully described.

Correlation Between Post-Radiosurgery Perinidal Hyperintensity and AVM Obliteration Following LINAC-Based Stereotactic Radiosurgery

OBJECTIVE

We studied the correlation between new-onset perinidal hyperintensity (PH) on T2-weighted magnetic resonance imaging and obliteration of intracranial arteriovenous malformation (AVM) after stereotactic radiosurgery (SRS).

METHODS

A retrospective study of 148 patients with an intracranial AVM who underwent SRS between September 2005 and June 2018 and had ≥1 radiological follow-up (early magnetic resonance imaging) 12-18 months after SRS was performed to analyze the correlation between PH (graded from 0 to 2) and AVM obliteration.

RESULTS

Of the 148 patients, 95 were male. The mean patient age was 27.7 ± 12.4 years. Of the 148 AVMs, 105 (70.9%) were obliterated at a median follow-up of 27 months (interquartile range, 14-48 months). The cumulative 3-, 5-, 10-year obliteration rate was 51.8%, 70.8%, and 91.8%, respectively. New-onset PH was observed in 58 AVMs (39.2%; 50 obliterated and 8 not obliterated). No association was found between the pretreatment variables or dose delivered and the development of PH. Grade 2 PH was associated with the risk of symptoms developing compared with grade 1 PH (37.5% vs. 4%; P = 0.002). Symptomatic PH was more likely to develop in patients with a larger AVM (P = 0.05). On multivariate analysis, the presence of a single draining vein (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.3-6.8), a lower median AVM volume (OR, 0.97; 95% CI, 0.6-0.89), a mean marginal radiation dose (OR, 1.29; 95% CI, 1.02-1.64), and the presence of PH (OR, 3.16; 95% CI, 1.29-7.71) were independent predictors of AVM obliteration.

CONCLUSIONS

The incidence of PH after SRS for AVM was 39.2%. PH was an independent predictor of AVM obliteration after SRS. Grade 2 PH and a larger AVM volume were associated with symptomatic PH.

Imaging Markers Associated With Radiation-Induced Changes in Brain Arteriovenous Malformations After Radiosurgery

BACKGROUND

Radiation-induced changes (RICs) in brain tissue, seen as increased perinidal T2-weighted hyperintensity on MRI, are commonly observed in patients with brain arteriovenous malformations (BAVMs) within 2 years after Gamma Knife (Elekta) radiosurgery (GKRS).

OBJECTIVE

To explore the imaging markers associated with RICs in patients with BAVMs.

METHODS

We retrospectively included 106 treatment-naïve patients with BAVMs who received GKRS alone between 2011 and 2018 and had ≥24 months of clinical and MRI follow-up. Pre-GKRS angiography and MRIs were analyzed for morphological characteristics and quantitative digital subtraction angiography parameters. RIC severity was categorized as mild (grade I), moderate (grade II), or severe (grade III). Firth logistic regression analysis was conducted to determine the associations between the parameters and RICs.

RESULTS

Among the 106 patients, 83 (78.3%) developed RICs, with 16 categorized as grade I, 62 as grade II, and 5 as grade III. RICs were symptomatic in 19 patients (17.9%). In multivariable models, BAVMs with a volume of >5 cm3 (odds ratio [OR]: 4.322, P = .024) and neoangiogenesis on angiography before treatment (OR: 3.846, P = .029), and thrombus within nidus or drainage vein on follow-up MRI (OR: 3.679, P = .001) were independently associated with grade II or III RICs. Symptomatic RICs were more likely to develop in basal ganglia or brainstem.

CONCLUSION

Large BAVMs and neoangiogenesis were associated with moderate to severe RICs in treatment-naïve patients with BAVMs. Our findings may assist with the complication risk assessment for these patients.