Insula

Eloquence

• Lies next to the internal capsule and basal ganglia, which Sawaya's grading classes as eloquent. (Sawaya et al. 1998; Türe et al. 1999)

What it does

• Lies deep to the frontal, parietal and temporal opercula, bounded by the circular sulcus and divided by the central insular sulcus into anterior short gyri and posterior long gyri. (Türe et al. 1999)

Arterial supply

• Supplied by insular branches of the M2 segments of the middle cerebral artery; most are short and end in the insular cortex and extreme capsule, while a minority of long branches reach the corona radiata. (Türe et al. 2000)

Venous drainage

• Insular veins drain to the deep middle cerebral vein, a tributary of the basal vein. (Rhoton 2002)

Deficits if injured

• Resection of insular tumours carries a risk of motor and language deficits, often transient. (Sanai et al. 2010)

Surgical relevance

• Long insular arteries supply the corona radiata, so their injury can cause motor deficits; the lenticulostriate arteries lie medial to the insula and limit resection. (Türe et al. 2000)

On the template

Desikan-Killiany. Values describe the fsaverage template, not an individual or a population norm.

Area: pial surface of the fsaverage average, which is smoother than individual cortex. Volume: voxel count of the fsaverage aseg segmentation at 1 mm isotropic.

References

1. Sawaya R, Hammoud M, Schoppa D, Hess KR, Wu SZ, Shi WM, et al.. Neurosurgical Outcomes in a Modern Series of 400 Craniotomies for Treatment of Parenchymal Tumors. Neurosurgery 1998;42(5):1044-1055. doi:10.1097/00006123-199805000-00054
2. Türe U, Yaşargil DCH, Al-Mefty O, Yaşargil MG. Topographic anatomy of the insular region. Journal of Neurosurgery 1999;90(4):720-733. doi:10.3171/jns.1999.90.4.0720
3. Türe U, Yaşargil MG, Al-Mefty O, Yaşargil DCH. Arteries of the insula. Journal of Neurosurgery 2000;92(4):676-687. doi:10.3171/jns.2000.92.4.0676
4. Rhoton AL. The Cerebral Veins. Neurosurgery 2002;51(suppl_4):S1-159-S1-205. doi:10.1097/00006123-200210001-00005
5. Sanai N, Polley MY, Berger MS. Insular glioma resection: assessment of patient morbidity, survival, and tumor progression. Journal of Neurosurgery 2010;112(1):1-9. doi:10.3171/2009.6.JNS0952