Alon Kashanian1, Hiro Sparks1, Tania Kaprealian2, Nader Pouratian3. 1. Department of Neurosurgery, David Geffen School of Medicine at UCLA (University of California, Los Angeles), 300 UCLA Stein Plaza, Suite 420, Los Angeles, CA, USA. 2. Department of Radiation Oncology, David Geffen School of Medicine at UCLA (University of California, Los Angeles), 200 UCLA Medical Plaza, Suite B265, Los Angeles, CA, USA. 3. Department of Neurosurgery, David Geffen School of Medicine at UCLA (University of California, Los Angeles), 300 UCLA Stein Plaza, Suite 420, Los Angeles, CA, USA; Department of Radiation Oncology, David Geffen School of Medicine at UCLA (University of California, Los Angeles), 200 UCLA Medical Plaza, Suite B265, Los Angeles, CA, USA. Electronic address: NPouratian@mednet.ucla.edu.
Abstract
BACKGROUND: Outcomes of stereotactic radiosurgery in the treatment of cerebral arteriovenous malformations (AVMs) are volume-dependent. The ability to estimate AVM volume has significant value in guiding AVM management. OBJECTIVE: To determine whether AVM volume measurement calculated from the ABC/2 formula is accurate compared to volume calculated by a computer-assisted planimetric method for large AVMs. METHODS: Retrospective review of 42 intracranial AVMs >3 cm in diameter that underwent treatment with dose-staged hypofractionated stereotactic radiotherapy (HSRT) from 2001 to 2018. Two raters independently measured pre- and post-HSRT volumes using both the ABC/2 formula and computer-assisted planimetry in a blinded fashion. Inter-rater reliability was assessed by calculation of intra-class correlation coefficient (ICC). Absolute volumes and percent volume change following HSRT as determined using the two methods were compared using paired t-tests, linear regression, and Bland-Altman plot analyses. RESULTS: The ICC between the 2 raters for planimetric and ABC/2 volumes was 0.859 and 0.799, respectively. ABC/2 volumes, 26.1 ± 26.6 cm3, were statistically smaller than planimetric volumes, 28.6 ± 27.1 cm3 (P = .008). Despite differences, the two methods were highly correlated (R2 = 0.904, linear regression). The percent volume change following HSRT was significantly greater with the ABC/2 method than compared to planimetry (P = .009). CONCLUSION: The ABC/2 and planimetric methods are reproducible for measuring cerebral AVM volumes. Although the ABC/2 method of volume estimation underestimates planimetric AVM volume, the high correlation between the two suggests utility of the ABC/2 method if one understands its limits, particularly with respect to estimating change in AVM volume after treatment.
BACKGROUND: Outcomes of stereotactic radiosurgery in the treatment of cerebral arteriovenous malformations (AVMs) are volume-dependent. The ability to estimate AVM volume has significant value in guiding AVM management. OBJECTIVE: To determine whether AVM volume measurement calculated from the ABC/2 formula is accurate compared to volume calculated by a computer-assisted planimetric method for large AVMs. METHODS: Retrospective review of 42 intracranial AVMs >3 cm in diameter that underwent treatment with dose-staged hypofractionated stereotactic radiotherapy (HSRT) from 2001 to 2018. Two raters independently measured pre- and post-HSRT volumes using both the ABC/2 formula and computer-assisted planimetry in a blinded fashion. Inter-rater reliability was assessed by calculation of intra-class correlation coefficient (ICC). Absolute volumes and percent volume change following HSRT as determined using the two methods were compared using paired t-tests, linear regression, and Bland-Altman plot analyses. RESULTS: The ICC between the 2 raters for planimetric and ABC/2 volumes was 0.859 and 0.799, respectively. ABC/2 volumes, 26.1 ± 26.6 cm3, were statistically smaller than planimetric volumes, 28.6 ± 27.1 cm3 (P = .008). Despite differences, the two methods were highly correlated (R2 = 0.904, linear regression). The percent volume change following HSRT was significantly greater with the ABC/2 method than compared to planimetry (P = .009). CONCLUSION: The ABC/2 and planimetric methods are reproducible for measuring cerebral AVM volumes. Although the ABC/2 method of volume estimation underestimates planimetric AVM volume, the high correlation between the two suggests utility of the ABC/2 method if one understands its limits, particularly with respect to estimating change in AVM volume after treatment.
Authors: Mehdi Yahia-Cherif; Chifra Fenton; Thomas Bonnet; Olivier De Witte; Stéphane Simon; Viviane De Maertelaer; Benjamin Mine; Florence Lefranc; Boris Lubicz Journal: Neuroradiology Date: 2022-10-22 Impact factor: 2.995
Authors: Faraz Behzadi; Daniel M Heiferman; Amy Wozniak; Benjamin Africk; Matthew Ballard; Joshua Chazaro; Brandon Zsigray; Matthew Reynolds; Douglas E Anderson; Joseph C Serrone Journal: J Cerebrovasc Endovasc Neurosurg Date: 2022-05-06