Resting state connectivity between default mode network and insula encodes acute migraine headache.

Background Previous functional MRI studies have revealed that ongoing clinical pain in different chronic pain syndromes is directly correlated to the connectivity strength of the resting default mode network (DMN) with the insula. Here, we investigated seed-based resting state DMN-insula connectivity during acute migraine headaches. Methods Thirteen migraine without aura patients (MI) underwent 3 T MRI scans during the initial six hours of a spontaneous migraine attack, and were compared to a group of 19 healthy volunteers (HV). We evaluated headache intensity with a visual analogue scale and collected seed-based MRI resting state data in the four core regions of the DMN: Medial prefrontal cortex (MPFC), posterior cingulate cortex (PCC), and left and right inferior parietal lobules (IPLs), as well as in bilateral insula. Results Compared to HV, MI patients showed stronger functional connectivity between MPFC and PCC, and between MPFC and bilateral insula. During migraine attacks, the strength of MPFC-to-insula connectivity was negatively correlated with pain intensity. Conclusion We show that greater subjective intensity of pain during a migraine attack is associated with proportionally weaker DMN-insula connectivity. This is at variance with other chronic extra-cephalic pain disorders where the opposite was found, and may thus be a hallmark of acute migraine head pain.

Ictal EEG/fMRI study of vertiginous seizures.

Vertigo and dizziness are extremely common complaints, related to either peripheral or central nervous system disorders. Among the latter, epilepsy has to be taken into consideration: indeed, vertigo may be part of the initial aura of a focal epileptic seizure in association with other signs/symptoms, or represent the only ictal manifestation, a rare phenomenon known as "vertiginous" or "vestibular" seizure. These ictal symptoms are usually related to a discharge arising from/involving temporal or parietal areas, which are supposed to be a crucial component of the so-called "vestibular cortex". In this paper, we describe three patients suffering from drug-resistant focal epilepsy, symptomatic of malformations of cortical development or perinatal hypoxic/ischemic lesions located in the posterior regions, who presented clusters of vertiginous seizures. The high recurrence rate of such events, recorded during video-EEG monitoring sessions, offered the opportunity to perform an ictal EEG/fMRI study to identify seizure-related hemodynamic changes. The ictal EEG/fMRI revealed the main activation clusters in the temporo-parieto-occipital regions, which are widely recognized to be involved in the processing of vestibular information. Interestingly, ictal deactivation was also detected in the ipsilateral cerebellar hemisphere, suggesting the ictal involvement of cortical-subcortical structures known to be part of the vestibular integration network.

Thalamo-cortical network activity between migraine attacks: Insights from MRI-based microstructural and functional resting-state network correlation analysis.

BACKGROUND: Resting state magnetic resonance imaging allows studying functionally interconnected brain networks. Here we were aimed to verify functional connectivity between brain networks at rest and its relationship with thalamic microstructure in migraine without aura (MO) patients between attacks. METHODS: Eighteen patients with untreated MO underwent 3 T MRI scans and were compared to a group of 19 healthy volunteers (HV). We used MRI to collect resting state data among two selected resting state networks, identified using group independent component (IC) analysis. Fractional anisotropy (FA) and mean diffusivity (MD) values of bilateral thalami were retrieved from a previous diffusion tensor imaging study on the same subjects and correlated with resting state ICs Z-scores. RESULTS: In comparison to HV, in MO we found significant reduced functional connectivity between the default mode network and the visuo-spatial system. Both HV and migraine patients selected ICs Z-scores correlated negatively with FA values of the thalamus bilaterally. CONCLUSIONS: The present results are the first evidence supporting the hypothesis that an abnormal resting within networks connectivity associated with significant differences in baseline thalamic microstructure could contribute to interictal migraine pathophysiology.

Intradural angiomatous meningioma arising from a thoracic nerve root.

BACKGROUND: Spinal intradural meningiomas that arise purely from a nerve root without dural attachments are extremely rare. Spinal meningiomas arise from arachnoidal cap cells in the spinal canal, and growth of these tumors exerts pressure on the spinal cord and nerve roots. CASE DESCRIPTION: A patient presented with a lesion at the T3-T4 level that resembled a schwannoma on magnetic resonance imaging. During surgery, the tumor originated from a spinal nerve root. Pathologically, it was an angiomatous meningioma (AM). CONCLUSIONS: In a review of the literature, we discuss the pathogenesis and surgical strategy for diagnosing and treating these extremely rare AM lesions.

Measurement of Bone Flap Surface Area and Midline Shift to Predict Overall Survival After Decompressive Craniectomy.

BACKGROUND: There is uncertainty about the optimal method for measuring the decompressive craniectomy (DC) surface area and how large the DC should be. METHODS: A radiological technique for measuring the surface area of removed bone flaps in a series of 73 DCs was developed. Preoperative and early postoperative computed tomography scans of each patient were evaluated. Midline shift (MLS) was considered the key factor for successful DC and was assigned to either normal (0-4 mm) or pathological (≥5 mm) ranges. The association between postoperative MLS and patient survival at 12 months was assessed. RESULTS: Measurements of all removed bone flaps yielded a mean surface area of 7759 mm2. The surface area of the removed bone flap did not influence survival (surviving 7643 mm2 vs. deceased 7372 mm2). The only factor associated with survival was reduced postoperative MLS (P < 0.034). Risk of death was 14.4 (3.0-70.1)-fold greater in patients with postoperative shift ≥5 mm (P < 0.001). CONCLUSION: The ideal surface area for "large" square bone flaps should result in an MLS of <5 mm. Enlargement of the craniectomy edges should be considered for patients in whom MLS ≥5 mm persists according to early postoperative computed tomography scans.