Dopamine hypersensitivity in migraine: role of the apomorphine test.

We investigated the effects of apomorphine administration at two different doses (2-10 micrograms/kg, s.c.) in 35 migraineurs in headache-free period and in 20 age-matched healthy control subjects, with and without pretreatment with domperidone. Neither patients or controls complained of headache at either dose, whereas at the dose of 10 micrograms/kg migraineurs showed a statistically significant higher incidence of dopaminergic symptoms (nausea, vomiting, drowsiness, yawning, dizziness, sweating) than controls. Furthermore, symptoms due to postsynaptic dopamine receptors activation (i.e., nausea and vomiting) only appeared in migraineurs. No symptom, however, resembled those characterizing a spontaneous migraine attack. In conclusion, migraineurs show a lower threshold for dopamine receptor activation than normal subjects.

Microembolization from a carotid mural thrombus detected by transcranial Doppler.

Over the last few years, many authors have described the possibility of using transcranial Doppler to demonstrate the passage of microemboli in the cerebral arteries. We report the case of a 44-year-old woman with thrombotic diathesis and thrombocytosis who was admitted twice within a short period of time (one and a half months) to a neurological department because of multiple cerebral infarctions. On the occasion of the second admission, a colour-Doppler examination of the epiaortic vessels, which had previously been negative, showed a carotid lesion due to a mural thrombus and, on the same side as the carotid lesion, transcranial Doppler detected short-duration, high-intensity signals in the middle and anterior cerebral arteries, an expression of the passage of microemboli. As already described by other authors in similar clinical situations, our case confirms that transcranial Doppler can identify the passage of microemboli in the circle of Willis.

Spontaneous middle cerebral artery reperfusion in ischemic stroke. A follow-up study with transcranial Doppler.

BACKGROUND AND PURPOSE: The aim of this study was to investigate by means of transcranial Doppler (TCD) ultrasonography how many spontaneous reperfusions of the middle cerebral artery (MCA) occurred during the first week after onset of acute ischemic stroke in the carotid territory. METHODS: TCD examination, computed tomographic scan, and arterial digital angiography were performed in 56 patients with acute ischemic stroke within 6 hours of the onset of symptoms. The TCD examination was repeated within 24 hours, 48 hours, and 7 days after stroke; a further TCD examination was performed within 3 to 9 months in 27 patients. RESULTS: At 6 hours, 33 patients presented abnormal TCD findings in the symptomatic MCA (16 "no flows" and 17 asymmetries). Of these, 4 patients (3 no flows and 1 asymmetry) died before the 7-day follow-up was completed, whereas of the 29 remaining patients undergoing all the TCD control examinations, only 14 presented permanently abnormal TCD findings (7 asymmetries and 7 no flows). These data are consistent with an MCA reperfusion occurring at any level of the MCA, although most frequently in the distal part, and in the majority of cases during the first 48 hours. One patient who showed MCA asymmetrical flow velocity at the day-7 TCD examination was normal at the TCD follow-up at 3 to 9 months. CONCLUSIONS: TCD examination offers an easy and reliable way of monitoring MCA reopening and might be useful to identify subgroups of patients who may benefit most from pharmacological reperfusion.

Transcranial Doppler in spontaneous attacks of migraine.

BACKGROUND AND PURPOSE: Our aim in this study was to compare headache-free and spontaneous migraine measurements of blood flow velocity and the pulsatility index in the anterior cerebral artery, middle cerebral artery, and posterior cerebral artery. METHODS: Thirty-one patients (nine having experienced migraine with aura and 22 migraine without aura) were studied in headache-free periods and during spontaneous migraine attacks with transcranial Doppler ultrasonography. RESULTS: During attacks of migraine with aura, blood flow velocities (particularly the diastolic velocity [p = 0.05]) were reduced while the pulsatility index increased (p = 0.05), whereas a generalized increase in diastolic velocity (p less than 0.02) and a decrease in the pulsatility index (p = 0.05) were observed during attacks of migraine without aura. Significant variations of blood pressure and heart rate were never found. CONCLUSIONS: These findings are consistent with constriction of resistance vessels in migraine with aura and dilatation of the vessels in migraine without aura. This disparity could be due to a difference between the two migraine types or could be related to the fact that in this study the time interval between headache onset and transcranial Doppler was shorter in the migraine-with-aura group. The latter explanation would apply if, in fact, both types of migraine evolve from hypoperfusion to hyperperfusion during their time course, although perhaps with a difference in intensity.

Transcranial Doppler (TCD) after nitroglycerin in migraine without aura.

Nitroglycerin, a vasodilating agent, was administered sublingually in migraine without aura patients and in healthy volunteers. Systolic, diastolic and time-mean flow velocity and pulsatility index, were measured by transcranial Doppler sonography in the major intracranial arteries before and after nitroglycerin administration. Following nitroglycerin administration, a significant decrease in systolic and time-mean velocity and pulsatility index was observed in migraine patients, whereas in control subjects only time-mean velocity decreased significantly. Based on those findings we hypothesize a more marked responsiveness to nitroglycerin in migraine patients as compared to healthy subjects.

Nimodipine in migraine: clinical efficacy and endocrinological effects.

Serum prolactin is increased during chronic flunarizine treatment of patients suffering from migraine. In order to clarify the role of calcium in control of the secretion of anterior pituitary hormones, a study has now been made of the effects of chronic nimodipine and propranolol treatment of migraine patients on prolactin (PRL), luteinizing hormone (LH) and growth hormone (GH) levels. 11 patients were treated with nimodipine and 8 with propranolol for four months. A statistically significant reduction in the frequency of the attacks was demonstrated in both groups. No significant change was found in the hormones levels during nimodipine treatment.

Comparison of cerebral angiography and transcranial Doppler sonography in acute stroke.

We compared digital intra-arterial angiography and transcranial Doppler sonography in acute cerebral ischemia as part of a wider study on a continuous series of 48 patients with acute focal cerebral ischemia in the carotid territory, observed within 4 hours of the onset of symptoms. The most significant Doppler findings of the middle cerebral artery included no detection of the artery when occlusion of the carotid siphon or the middle cerebral artery at its origin was shown by angiography and reduced flow velocities and asymmetry (symptomatic less than asymptomatic) when the occlusion was located in the terminal tract of the middle cerebral artery mainstem or in numerous terminal branches. Higher flow velocities in the anterior cerebral artery or posterior cerebral artery, mostly in the symptomatic hemisphere, often accompanied middle cerebral artery pathology, probably indicating collateral compensatory pathways.