Laszlo Szalontai1,2, Zsofia Jokkel1, Tamas Horvath3, Marton Piroska1, Bianka Forgo4, Csaba Olah5, Laszlo Kostyal6, David L Tarnoki1,2, Adam D Tarnoki1,2. 1. Medical Imaging Centre, Semmelweis University, 78/A Üllői Street, 1082 Budapest, Hungary. 2. Oncologic Imaging Diagnostic Center, Department of Radiology, National Institute of Oncology, Ráth György Street 7-9, 1122 Budapest, Hungary. 3. HeartBit, Hűvösvölgyi road 42, 1021 Budapest, Hungary. 4. Department of Radiology, Faculty of Medicine and Health, Örebro University, Södra Grev Rosengatan, 701 85 Örebro, Sweden. 5. Department of Neurosurgery, University of Debrecen, Nagyerdei Boulevard 98, 4032 Debrecen, Hungary. 6. Department of Radiology, Borsod County University Teaching Hospital, 72-76 Szentpéteri Gate, 3526 Miskolc, Hungary.
Abstract
Background and Objectives: The asymmetrical vertebral artery (VA) flow and diameter are common findings, which can result in an asymmetrical blood flow in the basilar artery (BA), leading to bending of the artery over time. This study investigated whether the variation of the different vertebrobasilar morphological indices that influence flow characteristics might be inherited. Materials and Methods: We analyzed 200 cerebral magnetic resonance imaging (MRI) scans of healthy Caucasian twins (100 pairs) who underwent time-of-flight MRI. From the scans, we reconstructed the 3D mesh of the posterior circulation from the start of the V4 segment to the basilar tip and subsequently analyzed the morphology of the vertebrobasilar system. The phenotypic covariances of the different morphological parameters were decomposed into heritability (A), shared (C), and unshared (E) environmental effects. Results: 39% of the twins had left dominant VA, while 32.5% had right dominant. In addition, 28.5% were classified as equal. The vertebral artery V4 segment diameter, curvature, and tortuosity were mainly influenced by shared (C) and unshared (E) environmental factors. A moderate heritability was found for the BA length (A: 63%; 95% CI: 45.7-75.2%; E: 37%; 95% CI: 24.8-54.3%) and volume (A: 60.1%; 95% CI: 42.4-73.2%; E: 39.9%; 95% CI: 26.8-57.6%), while the torsion of both arteries showed no heritability and were only influenced by the unshared environment. Conclusions: The length and volume of the BA show a moderate genetical influence. However, most of the measured morphological indices were influenced by shared and unshared factors, which highlight the role of the ever-changing hemodynamic influences shaping the geometry of the vertebrobasilar system.
Background and Objectives: The asymmetrical vertebral artery (VA) flow and diameter are common findings, which can result in an asymmetrical blood flow in the basilar artery (BA), leading to bending of the artery over time. This study investigated whether the variation of the different vertebrobasilar morphological indices that influence flow characteristics might be inherited. Materials and Methods: We analyzed 200 cerebral magnetic resonance imaging (MRI) scans of healthy Caucasian twins (100 pairs) who underwent time-of-flight MRI. From the scans, we reconstructed the 3D mesh of the posterior circulation from the start of the V4 segment to the basilar tip and subsequently analyzed the morphology of the vertebrobasilar system. The phenotypic covariances of the different morphological parameters were decomposed into heritability (A), shared (C), and unshared (E) environmental effects. Results: 39% of the twins had left dominant VA, while 32.5% had right dominant. In addition, 28.5% were classified as equal. The vertebral artery V4 segment diameter, curvature, and tortuosity were mainly influenced by shared (C) and unshared (E) environmental factors. A moderate heritability was found for the BA length (A: 63%; 95% CI: 45.7-75.2%; E: 37%; 95% CI: 24.8-54.3%) and volume (A: 60.1%; 95% CI: 42.4-73.2%; E: 39.9%; 95% CI: 26.8-57.6%), while the torsion of both arteries showed no heritability and were only influenced by the unshared environment. Conclusions: The length and volume of the BA show a moderate genetical influence. However, most of the measured morphological indices were influenced by shared and unshared factors, which highlight the role of the ever-changing hemodynamic influences shaping the geometry of the vertebrobasilar system.
Authors: Luca Antiga; Marina Piccinelli; Lorenzo Botti; Bogdan Ene-Iordache; Andrea Remuzzi; David A Steinman Journal: Med Biol Eng Comput Date: 2008-11-11 Impact factor: 2.602
Authors: Adam D Tarnoki; David L Tarnoki; Bianka Forgo; Helga Szabo; Dora Melicher; Julia Metneki; Levente Littvay Journal: Twin Res Hum Genet Date: 2020-01-07 Impact factor: 1.587