Preliminary reports have shown that hyperbaric oxygen (HBO) interrupts cluster headache (CH) attacks. In the present study, 6 of 7 patients with episodic cluster headache who were treated with hyperbaric oxygen experienced an interruption of the attack. In 3 of 6 responders the florid period of the cluster headache was interrupted. The other 3 patients remained without pain attacks for a period lasting from 3 to 6 days. In 6 different patients, a placebo treatment had no effect. The present findings clearly indicate that hyperbaric oxygen has not only a symptomatic effect on a single attack of cluster headache, but it also could prevent the occurrence of subsequent attacks.

Aim. Headache is one of the most common diseases associated with Temporomandibular Disorders (TMDs). The aim of this study was to evaluate, retrospectively, if headache influences TMD's symptoms. Material and Methods. A total sample of 1198 consecutive TMD patients was selected. After a neurological examination, a diagnosis of headache, according to the latest edition of the International Classification of Headache Disorders, was performed in 625 subjects. Patients were divided into two groups based on presence/absence of headache: Group with Headache (GwH) and Group without Headache (GwoH). Descriptive statistics and Chi-square index were performed. Results. Sociodemographic (gender, marital status, and occupation) and functional factors, occlusion (occlusal and skeletal classes, dental formula, and occlusal abnormalities), and familiar pain did not show a statistically significant correlation in either group. Intensity and frequency of neck pain, arthralgia of TMJ, and myalgia showed higher correlation values in GwH. Conclusion. This study is consistent with previous literature in showing a close relationship between headache and TMD. All data underlines that headache makes pain parameters more intense and frequent. Therefore, an early and multidisciplinary treatment of TMDs should be performed in order to avoid the overlay of painful events that could result in pain chronicity.

Fibromyalgia (FM) is thought to occur because of the combination of interactions among neurotransmitters, such as neuropeptide Y (NPY), stressors, hormones, cytokines, and both the immune and sympathetic nervous systems. The aim of this study was to evaluate serum concentrations of cytokines, antipolymer antibodies (APA), and NPY in 51 patients with FM, 25 with tension-type headache (TTH), and 15 healthy controls. Serum concentrations of eight different cytokines, APA and NPY, were measured. Interleukin (IL)-1RA, IL-6, IL-10, and tumor necrosis factor-alpha were higher in serum of FM patients compared with TTH patients and a significant correlation between IL-10 and Fibromyalgia Impact Questionnaire score was observed. There was a significant difference between FM and TTH versus controls in NPY levels, but not in APA levels. Cytokines and NPY take part in pain modulation and even if they are altered in FM they cannot be considered as measurable biomarkers of disease.

Exposure to hyperbaric oxygen has been shown to be effective in cluster headache, but the mechanism of the action is still not clear. Primary nociceptive neurons, containing neuropeptides such as substance P and particularly those innervating the nasal mucosa, could be involved in the pathogenesis of cluster headache. The present study evaluated the effect of an exposure to hyperbaric oxygen on the content of substance P in the nasal mucosa of patients affected by cluster headache. The results were compared with those observed in another group of cluster headache patients who underwent a placebo procedure. The samples of nasal mucosa were analyzed by immunocytochemical methods. A qualitative analysis of the slides was carried out by an operator under "blinded conditions". A marked decrease in the content of immunoreactivity for substance P was found in the patients exposed to hyperbaric oxygen. The decrease was statistically significant when compared with the findings of the placebo procedure. The results of the present study indicate that an influence on the content of peripheral neuropeptides could be involved in the mechanism of action of the beneficial effect of hyperbaric oxygen in cluster headache.

Habituation is considered one of the most basic mechanisms of learning. Habituation deficit to several sensory stimulations has been defined as a trait of migraine brain and also observed in other disorders. On the other hand, analytic information processing style is characterized by the habit of continually evaluating stimuli and it has been associated with migraine. We investigated a possible correlation between lack of habituation of evoked visual potentials and analytic cognitive style in healthy subjects. According to Sternberg-Wagner self-assessment inventory, 15 healthy volunteers (HV) with high analytic score and 15 HV with high global score were recruited. Both groups underwent visual evoked potentials recordings after psychological evaluation. We observed significant lack of habituation in analytical individuals compared to global group. In conclusion, a reduced habituation of visual evoked potentials has been observed in analytic subjects. Our results suggest that further research should be undertaken regarding the relationship between analytic cognitive style and lack of habituation in both physiological and pathophysiological conditions.