Dosimetric Analysis of Neural and Vascular Structures in Skull Base Tumors Treated with Stereotactic Radiosurgery.
Objective To examine the relationship between the prescribed target dose and the dose to healthy neurovascular structures in patients with vestibular schwannomas treated with stereotactic radiosurgery (SRS). Study Design Case series with chart review. Setting SRS center from 2011 to 2013. Subjects Twenty patients with vestibular schwannomas treated at the center from 2011 to 2013. Methods Twenty patients with vestibular schwannomas were included. The average radiation dose delivered to healthy neurovascular structures (eg, carotid artery, basilar artery, facial nerve, trigeminal nerve, and cochlea) was analyzed. Results Twenty patients with vestibular schwannomas who were treated with fused computed tomography/magnetic resonance imaging-guided SRS were included in the study. The prescribed dose ranged from 10.58 to 17.40 Gy over 1 to 3 hypofractions to cover 95% of the target tumor volume. The mean dose to the carotid artery was 5.66 Gy (95% confidence interval [CI], 4.53-6.80 Gy), anterior inferior cerebellar artery was 8.70 Gy (95% CI, 4.54-12.86 Gy), intratemporal facial nerve was 3.76 Gy (95% CI, 3.04-4.08 Gy), trigeminal nerve was 5.21 Gy (95% CI, 3.31-7.11 Gy), and the cochlea was 8.70 Gy (95% CI, 7.81-9.59 Gy). Conclusions SRS for certain vestibular schwannomas can expose the anterior inferior cerebellar artery (AICA) and carotid artery to radiation doses that can potentially initiate atherosclerotic processes. The higher doses to the AICA and carotid artery correlated with increasing tumor volume. The dose delivered to other structures such as the cochlea and intratemporal facial nerve appears to be lower and much less likely to cause immediate complications when shielded.
['Haidar|Yarah M|YM|', 'Bhatt|Jay M|JM|', 'Ghavami|Yaser|Y|', 'Moshtaghi|Omid|O|', 'Schwer|Amanda|A|', 'Chenery|Stafford|S|', 'Djalilian|Hamid R|HR|']
D000328:Adult D000368:Aged D002140:California D015331:Cohort Studies D018572:Disease-Free Survival D005260:Female D006801:Humans D016014:Linear Models D008279:Magnetic Resonance Imaging D008297:Male D008875:Middle Aged D016343:Monitoring, Intraoperative D009464:Neuroma, Acoustic D011379:Prognosis D011829:Radiation Dosage D016634:Radiosurgery D012189:Retrospective Studies D018570:Risk Assessment D019291:Skull Base D019292:Skull Base Neoplasms D025321:Surgery, Computer-Assisted D016019:Survival Analysis D014057:Tomography, X-Ray Computed D016896:Treatment Outcome
dosimetric analysis skull base tumors stereotactic radiosurgery