Table 1.
Migraine Imaging Studies Reporting Changes in Insula Function and Structure
| Migraine type | State of Migraine |
Method | Experimental Paradigm (Stimulation) |
Subjects N (M/F) |
Effect (+/−) |
Laterality (R/L) |
Region (A/P) |
Reference |
|---|---|---|---|---|---|---|---|---|
| Functional Studies | ||||||||
| MWOA | ictal | PET | GTN | 1 (1/0) | + | R+L | P | (Bahra et al., 2001) |
| MWA(2)/MWOA(3) | ictal/interictal | PET | spontaneous | 5 (0/5) | + | R+L | – | (Afridi et al., 2005a) |
| MWOA | Ictal/interictal | PET | GTN | 8 (3/5) | + | R | – | (Maniyar et al., 2014) |
| MWA(8)/MWOA(16) | ictal | PET | GTN | 24 (10/14) | + | R+L | – | (Afridi et al., 2005b) |
| Vestibular | ictal/interictal | PET | spontaneous | 2(0/2) +MC | + | R | P | (Shin et al., 2014) |
| MWOA | ictal | SPECT | magnesium/placebo | 40 (5/35) | + | R | – | (Koseoglu et al., 2008) |
| MWA(4)/MWOA(6) | interictal | fMRI | verbal stimuli | 10(1/9) +MC | + | R+L | A+P | (Eck et al., 2011) |
| MWA(6)/MWOA(14) | ictal/interictal | fMRI | olfactory stimuli | 20 (5/15) | + | R | A+P | (Stankewitz and May, 2011) |
| MWOA | interictal | fMRI | spontaneous | 23(6/17) +MC | + | R+L | A | (Xue et al., 2012) |
| MWA(11)/MWOA(11) | interictal | fMRI | spontaneous | 22(2/20)+C | + | R+L | A | (Hadjikhani et al., 2013) |
| Chronic | interictal | fMRI | spontaneous | 20 (3/17) | + | R+L | A | (Schwedt et al., 2013) |
| MWA (20)/MWOA (10) | ictal/interictal | fMRI | spontaneous/olfactory stimuli | 20 (4/16) | + | R+L | A | (Stankewitz et al., 2013) |
| MWOA | interictal | fMRI | spontaneous | 40 (12/28)+MC | + | L | – | (Zhao et al., 2013) |
| Migraine + allodynia | interictal | fMRI | spontaneous | 38 (6/32) +C | + | R | P | (Schwedt et al., 2014) |
| MWA(26)/MWOA(26) | interictal | fMRI connectivity | spontaneous | 52(18/34) +MC | - (MWA) | R | A | (Niddam 2015 25888585) |
| MWOA | interictal | fMRI connectivity | spontaneous | 15(3/12) +MC | + | R+L | A | (Tso 2015 25663219) |
| Structural Studies | ||||||||
| Episodic | interictal | MRI/fMRI | spontaneous | 22(11/11) +MC | +/− | L | P | (Maleki et al., 2012b) |
| MWOA | interictal | MRI/fMRI | spontaneous | 40(11/29) +MC | + | L | – | (Yuan et al., 2013b) |
| MWOA | interictal | MRI/VBM | spontaneous | 35(3/32)+C | – | R | A | (Schmidt-Wilcke et al., 2008) |
| Drug Effect Studies | ||||||||
| Healthy + Sumatriptan | – | fMRI | soft brush | 12(4/8) | +/− | – | A/P | (Kramer et al., 2007) |
| Healthy + Sumatriptan | – | fMRI | electrical stimuli | 12 (8/4) | + | R | A | (Yuan et al., 2013a) |
| CM + PCA (AO) | interictal | PET | spontaneous | 20(7/13) +MC | + | R | – | (Di et al., 2013) |
| MWOA+ Acupuncture | ictal | PET-CT | electro (EAT) | 30(12/18) +MC | + (EAT) | – | – | (Yang 2012 3480944) |
Key: MWOA- Migraine without Aura, MWA- Migraine with Aura, MC- Matched Controls, GTN- glyceryl trinitrate, pMRI- Perfusion MRI, DWI- Diffusion Weighted Imaging, CM- Chronic Migraine, PCA- Paracetamol Caffeine Aspirin, AO- Analgesic overuse
Search Terms: Literature search of migraine and insula was undertaken using PubMed (http://www.ncbi.nlm.nih.gov/pubmed). Keywords used included: migraine, insula, anti-migraine drugs, gray matter, episodic migraine, and chronic migraine. Additional strategies included manual searches for relevant articles from the selected papers’ reference lists as well as utilization of PubMed’s related articles function.