Biomedical subjects

Antonio Magrini

Publications and source records attributed to Antonio Magrini.

3 recordsLinked to original sources

PubMed2006

Recurrent paroxysmal positional vertigo related to oral contraceptive treatment.

Benign paroxysmal positional vertigo (BPPV) is a high-prevalence vestibular end-organ disorder caused by the detachment of utricular otoconia which float in the posterior or lateral semicircular canal. In the majority of cases the etiology of BPPV is unknown and it may follow viral infection, vascular disorders or head trauma. BPPV may be recurrent, with some authors demonstrating a correlation between recurrence and female gender. We report herein on ten cases (out of 289 diagnoses of BPPV) of recurrent idiopathic BPPV, occurring in healthy women receiving oral contraceptive treatment, which ceased after treatment suspension. It has been hypothesized that the impaired water and electrolyte balance, the variations of endolymphatic pH and the impairment of glucose or lipid metabolism induced by oral contraceptive treatment may cause otoconial degeneration and subsequent otoconia detachment and BPPV. The rarity of the finding (10/289) could account for the poor attention paid to the hormonal pathogenesis of BPPV.

Adult↗

PubMed2003

Vestibular compensation: analysis of postural re-arrangement as a control index for unilateral vestibular deficit.

Patients with an acute unilateral vestibular lesion show an impaired balance control. The initial presentation is vertigo followed by postural instability; but with time, the global balance functions can be completely restored by a process called vestibular compensation. The aim of our study was to evaluate short and long-term variations of postural parameters in 20 patients affected by vestibular neuritis (VN), and to compare these patients to 20 normal individuals using computerized static posturography (CSP) along with patient feedback throughout the spectral frequency analysis. This analysis showed in patients with no residual dizziness a frequency shift of body sway from low to middle frequencies as a probable expression of the compensatory strategies used by the central nervous system. On the other hand, patients with persistence of postural instability did not show any frequency shift. Our results seem to provide an early index of a proper occurring compensation so that we can adjust therapeutic protocols according to each patient's functional modifications.

Female↗

PubMedDate not supplied

Long-term postural abnormalities in benign paroxysmal positional vertigo.

Benign paroxysmal positional vertigo (BPPV) is a disorder in which patients suffer from acute rotatory vertigo due to the presence of free otoconial debris migrating into one or more semicircular canals during head movements and resulting in abnormal stimulation of the ampullary crest. A prolonged loss of equilibrium of unclear origin is also present. Static posturography is a useful tool for the study of postural control systems and their role in these abnormalities. The aim of the present study was to evaluate the frequency of body sway and long-term instability of BPPV patients by posturography frequency analysis. Twenty patients with canalithiasis of the posterior semicircular canal and 20 normal controls were subjected to static posturography. Informed consent was obtained from all subjects. Patients were tested 1 h after diagnosis, and 3 days and 12 weeks after the characteristic Epley repositioning maneuver. Patients with BPPV showed significantly increased body sway both on lateral (X) and anteroposterior (Y) planes compared to normal subjects. Corporal oscillation with a broad-frequency spectrum was observed in both closed and open eye tests. The repositioning maneuver decreased the X plane body sway, while the anteroposterior sway was unchanged. Twelve weeks after treatment, a normalization of the anteroposterior sway was observed. Results of this study suggest that the long-term postural disturbance associated with BPPV differs from the acute disequilibrium that subsides after canalith repositioning: the former is a sagittal plane/broad spectrum body sway, while the latter is primarily a frontal plane/low frequency sway. The Epley maneuver was shown to reduce frontal sway, a postural abnormality that might therefore be linked to posterior semicircular canal function. Conversely, the observed sagittal body sway was only partially relieved by the restoration of canal function, and therefore, may be more related to the chronic dizziness observed in these patients.

Adult↗