Impulsivity traits and awareness of motor intention in Parkinson's disease: a proof-of-concept study.

INTRODUCTION: In patients with Parkinson's disease (PD), impulsivity is still a matter of investigation. It has been hypothesized that impulsive personality traits may favour impulse control disorder (ICD) onset during dopaminergic therapy. In healthy subjects, a relationship between the awareness of motor intention and impulsive personality traits assessed by the Barratt impulsivity scale (BIS-11) has been reported. The aim of this study was to evaluate the relationship between the awareness of voluntary action and impulsivity traits in PD. METHODS: Twenty-eight PD patients (stages I-III on the Hoehn and Yahr scale) underwent an impulsivity trait assessment by the BIS-11 scale and a task based on the Libet's clock. Participants were requested to perform a self-initiated movement and report the time they first feel their intention to move (W-judgement) or the time of the actual movement (M-judgement). RESULTS: In patients with higher BIS-11 scores, the time lag between the W-judgement and the actual movement was significantly lower than in patients with lower BIS-11. No difference emerged in the M-judgement. CONCLUSION: Data suggest that also in PD patients, the impulsive personality trait is related to a "delayed" awareness of motor intention and therefore to a shorter interval to allow a conscious "veto" of the impending action. Characterization of the temporal profile of awareness of motor intention could prove useful in identifying PD patients at risk of developing ICDs during dopaminergic treatment.

Assessment of internal diameters of abdominal and femoral blood vessels in 250 living subjects using color Doppler ultrasonography.

Acquiring data about venous or arterial vessel size is important for several reasons, given the increasing incidence of thomboembolic phenomena and arterial aneurysms and the emerging new vascular techniques. We studied 250 healthy subjects (125 men and 125 women; age range: 50 to 91 years) with no known vascular pathology, nor hypertension, nor diabetes. We assessed the caliber of abdominal aorta, inferior vena cava, iliac and femoral arteries and viens by color doppler ultrasonography, and analyzed the results with regard to sex, height, weight and body surface of each subject. The mean caliber measure of the large abdominal vessels appeared lower than the value obtained from cadavers. There was a direct proportion between the left and right vessels of the same subject. The difference in vessel caliber between male and female subjects was statistically significant. There was no correlation between vessel caliber and age, height or body surface area.

Internal jugular vein valves: an assessment of prevalence, morphology and competence by color Doppler echography in 240 healthy subjects.

The presence of valves in the head and neck veins is known since classical anatomical dissections. Previous studies have investigated whether jugular veins show constant valves at their ostium and whether these valves are physiologically competent, but, unluckily, these studies have reported conflicting results. Further, recent observations have raised the question whether the incompetence of jugular vein valves might play a pivotal role in neurological disorders related to venous engorgement of the brain. In this study we examined 462 internal jugular veins by using an echocolorodoppler apparatus. In particular, we assessed the presence, morphology and competence of valves at their ostium. Unilateral jugular vein valves were present in 406 cases (88%), mainly on the right side. The most frequently observed morphology (75%, 305 cases) was the two-leaflet valve, and jugular vein valves were incompetent in the huge majority of cases (365 cases, 90%). Our findings confirm the anatomical variability predicted from classical anatomical studies but, unluckily, do not provide additional evidence on the possible role of jugular vein valves in physiology and pathology. Further studies are strongly needed to determine whether these valves actually play an important role in counteracting chest venous pressure and in preventing reflux towards the brain.

Evaluation of the pattern of proximal and distal occlusion and collateral circulation of lower limb arteries using combined contrast arteriography and color doppler ecography.

Lower limb peripheral arterial occlusive disease (PAOD) is highly prevalent and causes disability and poor quality of life. The purpose of our study was to evaluate the pattern of proximal and distal occlusion and collateral circulation of lower limb arteries using combined contrast arteriography and color doppler ecography. The study concerned 140 subjects (88 men and 52 women, age range 65-88 years) with symptomatic lower limb arterial disease (Fontaine's stage II) subsequent to the occlusion of vessels downstream from the subrenal aorta. The assessment of lower-extremity PAOD was performed by using the FRASI study three step protocol. The calculation of the Winsor index showed progressively lower haemodynamic compromission in distal occlusion. The more the site of occlusion was proximal, and the greater was its hemodynamic effect, although there was no statistically significance. A combined use of contrast arteriography and color doppler ecography appeared very useful in studying the anatomy of the occlusions and their haemodynamic impact, as well as in analysing the presence and the effects of collateral circles. These findings may be fundamental for identifying the most correct indications for surgical therapy and for selecting optimal strategies and prostheses.

Compensatory collateral circles in vertebral and carotid artery occlusion.

The obstructive disease of the supraaortic trunks has considerable clinical importance. Patients with the same grade of obstruction can display a wide spectrum of symptoms. Apart from the grade, etiology and localization of the obstruction, the presence of collateral circles plays an essential role in the determination of the symptoms. We selected all asymptomatic patients, undergoing a diagnostic investigation with EchoColorDoppler in a period of 13 years, in whom an occlusion of the common carotid artery, of the internal carotid artery or of the vertebral artery was present, and we studied the compensatory collateral circles. We considered 8 subjects affected by common carotid occlusion, 66 subjects with internal carotid occlusion and 24 subjects with vertebral artery occlusion. In the 8 subjects affected by common carotid occlusion, before the bifurcation, the collateral circle was realized by the superior thyroid arteries through the supraisthmic thyroid artery. All of the 66 subjects with internal carotid disease showed collateral circles through the ophthalmic branches and through the communicating arteries. In the 24 subjects with vertebral artery occlusion, the compensatory collateral circle was realized by the cervical, costocervical and occipital branches. In conclusion, the presence of an adequate hemodynamic compensation through a collateral circle represents an important positive prognostic factor and can avoid invasive procedures, thus avoiding possible complications.