The Gibraltar Sign

An Anatomic Landmark for Predicting Transverse Sinus Dominance Laterality on Conventional MRI

David Pettersson, Joel D. McLouth, Benjamin Addicott, Jeffrey Pollock, Ramon Barajas

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

BACKGROUND AND PURPOSE: Physiologic asymmetry of transverse sinus (TS) caliber is common and can lead to misinterpretation of magnetic resonance venography (MRV) studies of the brain. This retrospective study assesses the ability of multiple anatomic features on axial noncontrast T1-weighted images (T1WIs) of the brain to predict congenital TS dominance. METHODS: One hundred consecutively acquired combined MRI-MRV studies of the brain were reviewed. On noncontrast axial T1WI, each reviewer measured (1) inclination of the groove for the superior sagittal sinus (SSS), (2) angulation of the posterior falx, (3) laterality of the SSS flow void, and (4) laterality of the inferior-most occipital lobe. TS cross-sectional area was measured on noncontrast sagittal 2-dimensional time-of-flight MRV images and served as the reference standard. RESULTS: The bony groove for the SSS sloped down to the right in 65 of 100 patients and correctly predicted right TS dominance in 63 of 65 cases (97% positive predictive value [PPV]). The groove sloped down to the left in 24 of 100 patients and correctly predicted left TS dominance in 22 of 24 cases (92% PPV). Laterality of the SSS flow void, laterality of the inferior-most occipital lobe, and angulation of the posterior falx had 91% PPV, 82% PPV, and 74% PPV for predicting TS dominance, respectively. CONCLUSIONS: Multiple anatomic features seen on conventional axial T1WI can be used to predict the laterality of congenital TS dominance and can help inform the interpretation of MRV studies of the brain.

Original languageEnglish (US)
Pages (from-to)99-105
Number of pages7
JournalJournal of Neuroimaging
Volume28
Issue number1
DOIs
StatePublished - Jan 1 2018

Fingerprint

Gibraltar
Anatomic Landmarks
Transverse Sinuses
Superior Sagittal Sinus
Phlebography
Magnetic Resonance Spectroscopy
Occipital Lobe
Brain
Retrospective Studies

Keywords

  • cerebral venous thrombosis
  • Gibraltar sign
  • magnetic resonance venography
  • petalia
  • transverse sinus

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Clinical Neurology

Cite this

The Gibraltar Sign : An Anatomic Landmark for Predicting Transverse Sinus Dominance Laterality on Conventional MRI. / Pettersson, David; McLouth, Joel D.; Addicott, Benjamin; Pollock, Jeffrey; Barajas, Ramon.

In: Journal of Neuroimaging, Vol. 28, No. 1, 01.01.2018, p. 99-105.

Research output: Contribution to journalArticle

@article{84b9c682c80e481db162db39b2afb777,
title = "The Gibraltar Sign: An Anatomic Landmark for Predicting Transverse Sinus Dominance Laterality on Conventional MRI",
abstract = "BACKGROUND AND PURPOSE: Physiologic asymmetry of transverse sinus (TS) caliber is common and can lead to misinterpretation of magnetic resonance venography (MRV) studies of the brain. This retrospective study assesses the ability of multiple anatomic features on axial noncontrast T1-weighted images (T1WIs) of the brain to predict congenital TS dominance. METHODS: One hundred consecutively acquired combined MRI-MRV studies of the brain were reviewed. On noncontrast axial T1WI, each reviewer measured (1) inclination of the groove for the superior sagittal sinus (SSS), (2) angulation of the posterior falx, (3) laterality of the SSS flow void, and (4) laterality of the inferior-most occipital lobe. TS cross-sectional area was measured on noncontrast sagittal 2-dimensional time-of-flight MRV images and served as the reference standard. RESULTS: The bony groove for the SSS sloped down to the right in 65 of 100 patients and correctly predicted right TS dominance in 63 of 65 cases (97{\%} positive predictive value [PPV]). The groove sloped down to the left in 24 of 100 patients and correctly predicted left TS dominance in 22 of 24 cases (92{\%} PPV). Laterality of the SSS flow void, laterality of the inferior-most occipital lobe, and angulation of the posterior falx had 91{\%} PPV, 82{\%} PPV, and 74{\%} PPV for predicting TS dominance, respectively. CONCLUSIONS: Multiple anatomic features seen on conventional axial T1WI can be used to predict the laterality of congenital TS dominance and can help inform the interpretation of MRV studies of the brain.",
keywords = "cerebral venous thrombosis, Gibraltar sign, magnetic resonance venography, petalia, transverse sinus",
author = "David Pettersson and McLouth, {Joel D.} and Benjamin Addicott and Jeffrey Pollock and Ramon Barajas",
year = "2018",
month = "1",
day = "1",
doi = "10.1111/jon.12457",
language = "English (US)",
volume = "28",
pages = "99--105",
journal = "Journal of Neuroimaging",
issn = "1051-2284",
publisher = "Wiley-Blackwell",
number = "1",

}

TY - JOUR

T1 - The Gibraltar Sign

T2 - An Anatomic Landmark for Predicting Transverse Sinus Dominance Laterality on Conventional MRI

AU - Pettersson, David

AU - McLouth, Joel D.

AU - Addicott, Benjamin

AU - Pollock, Jeffrey

AU - Barajas, Ramon

PY - 2018/1/1

Y1 - 2018/1/1

N2 - BACKGROUND AND PURPOSE: Physiologic asymmetry of transverse sinus (TS) caliber is common and can lead to misinterpretation of magnetic resonance venography (MRV) studies of the brain. This retrospective study assesses the ability of multiple anatomic features on axial noncontrast T1-weighted images (T1WIs) of the brain to predict congenital TS dominance. METHODS: One hundred consecutively acquired combined MRI-MRV studies of the brain were reviewed. On noncontrast axial T1WI, each reviewer measured (1) inclination of the groove for the superior sagittal sinus (SSS), (2) angulation of the posterior falx, (3) laterality of the SSS flow void, and (4) laterality of the inferior-most occipital lobe. TS cross-sectional area was measured on noncontrast sagittal 2-dimensional time-of-flight MRV images and served as the reference standard. RESULTS: The bony groove for the SSS sloped down to the right in 65 of 100 patients and correctly predicted right TS dominance in 63 of 65 cases (97% positive predictive value [PPV]). The groove sloped down to the left in 24 of 100 patients and correctly predicted left TS dominance in 22 of 24 cases (92% PPV). Laterality of the SSS flow void, laterality of the inferior-most occipital lobe, and angulation of the posterior falx had 91% PPV, 82% PPV, and 74% PPV for predicting TS dominance, respectively. CONCLUSIONS: Multiple anatomic features seen on conventional axial T1WI can be used to predict the laterality of congenital TS dominance and can help inform the interpretation of MRV studies of the brain.

AB - BACKGROUND AND PURPOSE: Physiologic asymmetry of transverse sinus (TS) caliber is common and can lead to misinterpretation of magnetic resonance venography (MRV) studies of the brain. This retrospective study assesses the ability of multiple anatomic features on axial noncontrast T1-weighted images (T1WIs) of the brain to predict congenital TS dominance. METHODS: One hundred consecutively acquired combined MRI-MRV studies of the brain were reviewed. On noncontrast axial T1WI, each reviewer measured (1) inclination of the groove for the superior sagittal sinus (SSS), (2) angulation of the posterior falx, (3) laterality of the SSS flow void, and (4) laterality of the inferior-most occipital lobe. TS cross-sectional area was measured on noncontrast sagittal 2-dimensional time-of-flight MRV images and served as the reference standard. RESULTS: The bony groove for the SSS sloped down to the right in 65 of 100 patients and correctly predicted right TS dominance in 63 of 65 cases (97% positive predictive value [PPV]). The groove sloped down to the left in 24 of 100 patients and correctly predicted left TS dominance in 22 of 24 cases (92% PPV). Laterality of the SSS flow void, laterality of the inferior-most occipital lobe, and angulation of the posterior falx had 91% PPV, 82% PPV, and 74% PPV for predicting TS dominance, respectively. CONCLUSIONS: Multiple anatomic features seen on conventional axial T1WI can be used to predict the laterality of congenital TS dominance and can help inform the interpretation of MRV studies of the brain.

KW - cerebral venous thrombosis

KW - Gibraltar sign

KW - magnetic resonance venography

KW - petalia

KW - transverse sinus

UR - http://www.scopus.com/inward/record.url?scp=85040112341&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85040112341&partnerID=8YFLogxK

U2 - 10.1111/jon.12457

DO - 10.1111/jon.12457

M3 - Article

VL - 28

SP - 99

EP - 105

JO - Journal of Neuroimaging

JF - Journal of Neuroimaging

SN - 1051-2284

IS - 1

ER -