AbstractCluster headache (CH) is a highly disabling primary headache disorder, characterized by strictly unilateral, excruciating pain in the distribution of the trigeminal nerve with associated cranial autonomic symptoms, that has a significant impact on patients’ health-related quality of life (HRQoL). There has been great interest over the years in elucidating the pathogenesis of this disorder.
This thesis adopted a mixed methods approach, using saccadometry and functional magnetic resonance imaging (fMRI) studies to gain better insight to the underlying processes involved, whilst also studying the disability and resultant impact it has on patients’ HRQoL. Arterial spin labeling (ASL) was utilized to identify changes in regional cerebral blood flow (rCBF) relating to brain responses to a greater occipital nerve block (GONB), which is a widely used transitional treatment. Significant activations were observed during the interictal period in several brain regions known to be involved in pain processing, including the posterior hypothalamus, a structure that has been hypothesized to have a crucial role in CH. This implies that a central permissive state exists during a bout, with subsequent deactivations following the GONB. A study of visual saccadic latencies revealed that CH patients have longer mean latencies with high variability and reduced number of fast saccades. This suggests that there is a delay in decision-making in CH patients, possibly stemming from basal ganglia dysfunction, with high variability of latencies arising from probable dysfunction within the noradrenergic system. This corresponds with the fMRI findings, therefore suggesting a pivotal role of these systems in CH pathophysiology.
Due to the lack of a specific HRQoL measure for CH, a 28-item CH specific HRQoL (CHQ) scale was developed and validated, showing good internal consistency, validity and test-retest reliability. An assessment made of the HRQoL confirmed the significant impact it has on patients’ lives, especially for those with the chronic variant.
|Date of Award
|Matthew Howard (Supervisor) & Tara Renton (Supervisor)