PubMed Health⌕ Search

Biomedical subjects

Miles J Levy

Publications and source records attributed to Miles J Levy.

7 recordsLinked to original sources

Pituitary volume and headache: size is not everything.

BACKGROUND: Pituitary tumors are commonly associated with disabling headache. The accepted mechanisms for headache are dural stretch and cavernous sinus invasion. OBJECTIVE: To determine if there is a relationship between pituitary tumor size and the report of headache. DESIGN: We prospectively studied 63 patients who were initially seen with pituitary tumors. Clinical headache scores, pituitary tumor volume, and the extent of cavernous sinus invasion were obtained for each patient. RESULTS: The prevalence of headache was 70%. There was no positive correlation the between clinical headache score and pituitary volume (r = -0.32, P =.01, Spearman rank correlation). There was also no association between cavernous sinus invasion and headache. There was a strong association between pituitary-associated headache and a family history of headache (chi(2) = 8.36, P =.004). CONCLUSIONS: These data suggest that a pituitary tumor-associated headache may not simply be a structural problem. Other factors such as family history of headache, and the endocrine activity of the tumor may be equally important determinants of headache. Elucidating these mechanisms will aid in the treatment of these patients and further our understanding of other headache syndromes.

Cavernous Sinus↗

Subcutaneous octreotide in cluster headache: randomized placebo-controlled double-blind crossover study.

Current practical evidence-based acute treatments of cluster headache are limited to subcutaneous and intranasal formulations of sumatriptan, and oxygen. Two small randomized, double-blind trials suggested efficacy of somatostatin in cluster headache. We sought to determine whether octreotide, a somatostatin analog, is effective in the abortive treatment of acute cluster headache. Patients with episodic and chronic cluster headache, as defined by the International Headache Society, were recruited to a double-blind placebo-controlled crossover study. Patients were instructed to treat two attacks of at least moderate pain severity, with at least a 24-hour break, using subcutaneous octreotide microg or matching placebo. The primary end point was the headache response defined as very severe, severe, or moderate pain becomes mild or nil, at 30 minutes. The primary end point was examined using a multilevel analysis approach. A total of 57 patients were recruited of whom 46 provided efficacy data on attacks treated with octreotide and 45 with placebo. The headache response rate with subcutaneous octreotide was 52%, whereas that with placebo was 36%. Modeling the treatment outcome as a binomial where response was determined by treatment, using the patient as the level 2 variable, and considering period effect, sex, and cluster headache type as other variables of interest, we found that the effect of subcutaneous octreotide 100 microg was significantly superior to placebo (p < 0.01). Subcutaneous octreotide 100 microg is effective in the acute treatment of cluster headache when compared with placebo. Nonvasconstrictor treatment of acute cluster headache is possible.

Adolescent↗

Hypothalamic activation after stimulation of the superior sagittal sinus in the cat: a Fos study.

Clinical observations, particularly of the premonitory phase of migraine, suggest the involvement of the hypothalamus in the earliest phases of an attack. Stimulation of the superior sagittal sinus (SSS) in humans produces head pain and permits study of the activated trigeminovascular system in experimental settings. The distribution of neurons expressing the protein product (Fos) of the c-fos immediate early gene was examined in the hypothalamus of anaesthetised (alpha-chloralose) cats. Animals were studied after either 2-h stimulation of the SSS or sham stimulation. Fos protein was detected using immunohistochemistry, and positive neurons were plotted onto standardised templates and counted by a blinded observer. In response to electrical stimulation of the superior sagittal sinus, we found significant activation of the supra-optic nucleus (SON) rising from 3 (0-13) (median, 95% confidence interval) to 53 (31-78; P = 0.005) fos-positive cells. In the posterior hypothalamic area (Hp), fos-positive cells rose from 4 (0-14) to 35 (17-45; P = 0.015) Taken together with other physiological studies, the data are consistent with a role for hypothalamic structures in the modulation of trigeminovascular nociceptive afferent information, and thus for a role in headache.

Animals↗

Prostaglandin E2 injected into the posterior hypothalamus has no effect on trigeminal nociception in the rat.

Craniovascular prostaglandin E2 (PGE2) release is elevated in the headache phase of migraine and in experimental models of headache. PGE2 synthesised in the brain may be involved in modulating trigeminal nociception. We examined whether PGE2 injected into the posterior hypothalamus could modulate trigeminovascular nociception. In seven rats, electrophysiological recordings were made from trigeminal nucleus caudalis neurons responsive to noxious middle meningeal artery stimulation and inhibited by bicuculline activation of the posterior hypothalamus. Microinjection into the posterior hypothalamus of a non-pyrogenic dose of PGE2 (2.5 microg/ml) produced no effect on nociceptive trigeminal nucleus caudalis neurons compared with saline injection (P=0.29). The mean response to PGE2 injection was 97% of baseline. We conclude that PGE2 in the posterior hypothalamus is unlikely to play a significant role in modulating trigeminal nociception.

Animals↗

Somatostatin infusion withdrawal: a study of patients with migraine, cluster headache and healthy volunteers.

Migraine and cluster headache are the most common disabling primary headache syndromes and are typically episodic. A reliable method of triggering such headache attacks facilitates the study and treatment of these disorders. There is sufficient clinical and laboratory evidence to suggest that somatostatin withdrawal may be a useful way of triggering headache. We studied 15 subjects, eight migraineurs, four cluster headache sufferers and three healthy controls. Each subject had a standard somatostatin infusion, 250 microg/h for 3.5h. Subjects were followed for 24h post-infusion. Growth hormone was suppressed in each subject demonstrating a biologically active infusion of somatostatin. None of the non-headache sufferers had pain. Seven of eight migraine sufferers had no immediate headache and no delayed headache. One migraineur experienced short lasting headache with no migrainous features. Three of four patients with cluster headache had no significant pain with the infusion, while one had pain after 1h. The results suggest that somatostatin infusion is not a reliable way to produce headache in experimental settings in either migraine or cluster headache. The data do not exclude a role for somatostatinergic mechanisms in primary headache.

Adult↗