Macroanatomy and 3D probabilistic atlas of the human insula.
The human insula is implicated in numerous functions. More and more neuroimaging studies focus on this region, however no atlas offers a complete subdivision of the insula in a reference space. The aims of this study were to define a protocol to subdivide insula, to create probability maps in the MNI152 stereotaxic space, and to provide normative reference volume measurements for these subdivisions. Six regions were manually delineated bilaterally on 3D T1 MR images of 30 healthy subjects: the three short gyri, the anterior inferior cortex, and the two long gyri. The volume of the insular grey matter was 7.7 ± 0.9cm3in native space and 9.9 ± 0.6cm3in MNI152 space. These volumes expressed as a percentage of the ipsilateral grey matter volume were minimally larger in women (2.7±0.2%) than in men (2.6±0.2%). After spatial normalization, a stereotactic probabilistic atlas of each subregion was produced, as well as a maximum-probability atlas taking into account surrounding structures. Automatically labelling insular subregions via a multi-atlas propagation and label fusion strategy (MAPER) in a leave-one-out experiment showed high spatial overlaps of such automatically defined insular subregions with the manually derived ones (mean Jaccard index 0.65, corresponding to a mean Dice index of 0.79), with an average mean volume error of 2.6%. Probabilistic and maximum probability atlases and the original delineations are available on the web under free academic licences.
Neurology Department - Hôpital Nord, 42055 Saint-Etienne, France; Central Integration of Pain Unit - Lyon Center for Neuroscience (CRNL), INSERM1028, 69675 Lyon, France.
Isabelle
I
Faillenot
Neurodis Foundation, 69675 Lyon, France; MedTech West at Sahlgrenska University Hospital, University of Gothenburg, Sweden; Division of Brain Science, Imperial College London, UK.
Rolf A
RA
Heckemann
Central Integration of Pain Unit - Lyon Center for Neuroscience (CRNL), INSERM1028, 69675 Lyon, France; Claude Bernard University Lyon 1, Villeurbanne 69000, France.
Maud
M
Frot
Neurodis Foundation, 69675 Lyon, France; King's College London & Guy's and St Thomas' PET Centre, King's College London, Division of Imaging Sciences and Biomedical Engineering, London, UK. Electronic address: alexander.hammers@kcl.ac.uk.
Alexander
A
Hammers
D000328:Adult; D000716:Anatomy, Artistic; D001271:Atlases as Topic; D002540:Cerebral Cortex / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging; D055815:Young Adult
Computer-assisted image processing; Insula anatomy; Magnetic resonance imaging methods; Neuroanatomy; Neurological models; Sex characteristics; Statistics and numerical data