Connectometry evaluation in patients undergoing carotid endarterectomy: an exploratory study

  • Michele PorcuEmail author
  • Davide Craboledda
  • Paolo Garofalo
  • Giulio Columbano
  • Luigi Barberini
  • Roberto Sanfilippo
  • Fulvio Zaccagna
  • Max Wintermark
  • Roberto Montisci
  • Luca Saba


This research investigated local brain connectivity changes following Carotid Endarterectomy (CEA) by connectometry. Seventeen subjects (15 males and 2 females, mean age 74.1 years), all eligible for CEA, were prospectively recruited in this exploratory study. On the same day within the week before the CEA, each patient underwent a cognitive evaluation with a Mini Mental State Examination (MMSE) and a Magnetic Resonance Imaging (MRI) exam that included a DTI sequence for the connectometry analysis. A second MMSE and the same MRI protocol were performed on follow-up, 3–6 months after CEA. The MMSE scores were analyzed using T-Student tests. The connectometry analysis was performed using a multiple regression model to consider the effect of CEA, choosing three different T-score threshold (T-threshold) values (1, 2 and 3). Results were considered statistically valid for p value adjusted for False Discovery Rate (p-FDR) < 0.05. Comparison of pre-CEA and post-CEA MMSE scores showed improvement of MMSE scores after CEA. Connectometry analysis revealed no areas of statistically significant increased connectivity related to CEA for T-threshold value = 1 and 2, but showed statistically significant increase of connectivity after CEA in both cerebellar hemispheres and corpus callosum for T-threshold value = 3 (p-FDR = 0.0106667). The network property analysis showed improved small worldness (2.14%), clustering coefficient (1.64%), local (1.94%) and global efficiency (0.56%), and reduced characteristic path length (−0.52%) after CEA. These results suggest that CEA is associated both with cognitive performance improvement and changes in interhemispheric local connectivity in the corpus callosum and cerebellum.


Carotid endarterectomy DTI Connectometry 


Compliance with ethical standards

Conflict of interest

All the authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Michele Porcu
    • 1
    • 2
    Email author
  • Davide Craboledda
    • 3
  • Paolo Garofalo
    • 1
  • Giulio Columbano
    • 1
  • Luigi Barberini
    • 4
  • Roberto Sanfilippo
    • 3
  • Fulvio Zaccagna
    • 5
  • Max Wintermark
    • 6
  • Roberto Montisci
    • 3
  • Luca Saba
    • 1
  1. 1.Department of RadiologyUniversity Hospital of CagliariCagliariItaly
  2. 2.Department of Medical Sciences and Public HealthUniversity of CagliariMonserratoItaly
  3. 3.Department of Vascular SurgeryUniversity Hospital of CagliariCagliariItaly
  4. 4.Department of Medical Sciences and Public HealthUniversity of CagliariCagliariItaly
  5. 5.Department of RadiologyUniversity of Cambridge School of Clinical MedicineCambridgeUK
  6. 6.Department of Radiology, Neuroradiology DivisionStanford UniversityStanfordUSA

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