Valentina Mattei

Chronic cerebrospinal venous insufficiency in Meniere disease

Objectives The aim of this study was to focus on patients suffering from cochleo-vestibular disorder with and without Ménière disease (MD) in order to verify whether chronic cerebrospinal drainage abnormalities could play a role in the etiopathogenesis of endolymphatic hydrops. Methods Fifty-two volunteers were enrolled and subdivided into two groups: 24 definite MD and 28 not-MD. Both magnetic resonance venography imaging with contrast-enhanced imaging of the venous cerebrospinal system (MRV) and venous echo-color Doppler (ECD) were performed. Results MRV showed abnormalities in 83% of MD and 57% of not-MD subjects (p < 0.001). Asymmetrical cervical venous flow, assessed by MRV, was confirmed by ECD in 62.5% of MD but in only 21.5% of not-MD subjects (p<0.001). Conclusion Chronic cerebrospinal venous insufficiency might be the anatomical background, which provides a predisposing factor for the development of endolymphatic hydrops in MD patients.

Figure ice skating induces vestibulo-ocular adaptation specific to required athletic skills

The aim of the paper is to investigate whether rotational vestibulo-ocular and visuo-vestibulo-ocular reflexes may undergo different adaptive gain changes depending on specific athletic motor skills required by the different specialities of figure skating. Twenty-five right-handed athletes from the Italian National Figure Skating Team were investigated, divided into three groups according to their discipline: 8 dancers, 13 singles and 4 pairs. Rotational vestibulo-ocular and visuo-vestibuloocular reflexes were recorded by electrooculography as slow phases of per-rotatory nystagmus during 0.10-Hz sinusoidal stimulation, respectively, in the darkness and in the light. Gain was reduced only in dancers whereas it was normal in singles and pairs. A clearcut clockwise directional preponderance was revealed only in dancers. The results confirm that, also from a vestibular point of view, singles and dancers look different, with pairs as an intermediate pattern. Furthermore, it has been shown that the human rotational vestibulo-ocular system is capable of asymmetric adaptation. Alterations in rotational vestibulo-ocular parameters observed in figure skaters result from vestibular habituation, but these kind of adaptations depend on the athletic tasks specific for each discipline, and they provide evidence for interdependent mechanisms for control of clockwise and counterclockwise oculomotor control at least in the low-frequency stimulation domain.

Characteristics of multiple sclerosis patient stance control disorders, measured by means of posturography and related to brainstem lesions.

Balance disorders are commonly observed during the course of multiple sclerosis (MS). The aim of this study is to report characteristics of MS patient stance control disorders, measured by means of posturography and related to the brainstem lesions. Thirty-eight patients affected by MS, mildly to moderately disable according to Kurtzkes Expanded Disability Status Scale, underwent a complete clinical neurological and vestibular evaluation and brain MRI scanning. All patients were then tested on a static posturography platform (Tetrax, Israel) in four conditions: eyes open and eyes closed standing on a firm surface and on a foam pad. Clinical and/or magnetic resonance imaging evidence of brainstem involvement was observed in 55.3% of patients. When brainstem lesion was detected, Fourier analysis showed a typical pattern characterized by inversion of the 0–0.1 Hz and 0.1–0.25 Hz frequency bands. In conclusion, MS leads to pervasive postural disturbances in the majority of subjects, including the visuo-vestibular loops and proprioception involving vestibulo-spinal pathways in at least 55.3% of patients. Our results may also suggest the presence of Fourier inversion in patients with brainstem lesions.

A manually operated device for the treatment of residual middle ear effusion and Eustachian tube dysfunction

Dear Sir Following recovery from otitis media, middle ear function might not be completely restored. Symptoms such as fullness, blockage in the ear or discomfort and sound distortion, as well as difficulties in speech perception, might continue for weeks, despite a normal pure tone audiogram or tympanogram. The continuation of symptoms can be explained by residual effusion and persisting Eustachian tube dysfunction. Pure tone audiometry and tympanometry can fail to demonstrate a suspected Eustachian tube dysfunction, so Morimitsu et al. introduced tubotympanometry and documented this technique to accurately measure residual Eustachian tube dysfunction (1). Recently, Wang et al. included vestibular evoked myogenic potentials (VEMPs) to detect residual middle ear conduction impairment (2). Typically it shows a delay in the latencies P13 and N23 while the interpeak latencies remain normal. We have gained experience in gently unblocking persisting fullness in the ears by employing a pocketsized manually operated device called the N-300 (Enttex, Port Melbourne, Australia). It has been developed to specifically unblock the middle ear fullness experienced with air travel and diving. The N-300 operates by applying mild negative pressure to the sealed external ear canal. This helps to unlock the Eustachian tube, and thus facilitates middle ear ventilation when swallowing (Figure 1). The N-300 has a safety valve that prevents creation of excessive pressures in the external ear canal, and does not exceed 350 400 mmH2O. Method

Self-experienced virtual reality to improve balance reflexes in ice dancers. A pilot study

The aim of the experiments was to use virtual reality stimulation to reweight visuovestibular sensory inputs in order to improve balance performances in ice dancers. In five athletes (three women and two men, mean age 22.5 years) from the Italian National Team rotational ocular reflexes were studied, both in the dark (rotational vestibuloocular reflex r-VOR) and in the light (rotational visuovestibuloocular reflex, r-VVOR). The athletes were rotated on a motorized chair and ocular reflexes were recorded by electrooculography. Skaters trained once a day for 20 days to maintain a one-leg stance on an oscillating platform during semi-immersion in a projected video acquired by a digital photocamera fixed to their head when they were skating. r-VOR gain increased significantly (p<0.001) in the three athletes with the lowest pretraining values. The virtual reality technique adopted is also as easy to perform in the usual training context, can be proposed as a low-cost well-tolerated approach also for specific training of patients with poor balance at least when oculomotor performance has to be optimized.

Stance instability in preclinical SCA1 mutation carriers: A 4-year prospective posturography study

OBJECTIVE We aimed to study postural balance in preclinical Spinocerebellar ataxia type 1 (SCA1) mutation carriers to identify and observe specific motor functional deficit before evident clinical manifestation. METHODS Participants were 9 asymptomatic SCA1 mutation carriers (6M/3F), aged 31.8±7years (range 22-44), and 17 age-matched non-carrier controls (5M/12F) (age 18-42). Subjects underwent postural tests on a force platform (Tetrax®-IBS, Sunlight Medical Ltd.) with and without visual feedback. Amount of body sway was represented by stability index (ST). Tests were repeated after 2- and 4-years. Estimated years to onset were calculated. RESULTS In controls, ST was unchanged from baseline to 4-year evaluations in all standing conditions. SCA1 mutation carriers performed similarly to controls in the postural tasks with open eyes, whereas in conditions without visual feedback SCA1 carriers had significantly higher ST than controls at all longitudinal evaluations. Close-to-disease onset carriers (≤7years) showed more prominent time-dependent stance abnormalities (p<0.0001 for all comparisons). CONCLUSIONS Traceable and progressive postural abnormalities can be observed in preclinical close-to-onset SCA1 carriers. Quantitative analysis of stance could represent a promising outcome measure in clinical trials including preclinical subjects.

Vestibular adaptation in ice skaters depends on discipline rather than age: some considerations about navigational control

Clear-cut differences have been described in both postural control and ocular reflexes in ice figure skaters between dancers and singles. We have previously shown that at least in long-trained athletes (that to say senior athletes) these kinds of adaptations depend on the tasks specific to each ice skating discipline providing evidence of interdependent mechanisms for vestibular control of clockwise and counter-clockwise oculomotion. The aim of this study was to determine if vestibuloocular adaptation depends on age or on discipline. The study group comprised 23 right-handed athletes from the Junior Italian National Figure Skating Team. They were divided into two groups: 8 dancers (4 girls and 4 boys, mean age 15.7 years), and 15 singles (8 girls and 7 boys, mean age 15.6 years). Rotational ocular reflexes were recorded by bitemporal DC-coupled electro-oculography as slow phases of per-rotatory nystagmus during rotation in the dark (rotational vestibuloocular reflex) and in the light (rotational visuovestibuloocular reflex). For both tests only directional preponderance was considered because the previous study showed the most clear-cut difference between dancers and singles. Our results support the idea that navigational strategies in ice skaters are dependent mainly on discipline rather than on age (that to say years of training). In particular, vestibular adaptation was independent of age while visuovestibular adaptation was dependent on age and represents a “dynamic internal model” of the relationships among visual, vestibular and proprioceptive inputs into the central processing system that depend on specific stimuli induced by different discipline-dependent activities.

The correlation between dental occlusion and posture is different in trained versus nontrained subjects

A relationship between postural control and occlusion is known and the postural variation after a change in occlusion might be different in athletes compared to sedentary subjects. Ten healthy sedentary subjects (nontrained group) and ten healthy athletic subjects (athlete group) were studied by static posturography with and without the interposition of cotton rolls between opposing teeth. Postural control was only slightly modified by the change in occlusion in the nontrained group (p ns) while postural strategies in the athlete group changed significantly (p < 0.001). In the athlete group, the change in occlusion resulted in sensory reorganization with an increase in the visual component and a reduction in the somatosensory component.

The Cervico-Cephalic Interaction

While the first function of posture is an antigravity function, the second one is to provide an interface with the external world for perception and action. For this reason, body posture is built up by a set of assembled segments with own mass that are linked together by flexible joints controlled by the neuromuscular system. Posture based on the superimposed segments (the head, the trunk and legs) is under the specific automatic central and peripheral control preserving the specific orientation of each segment with respect to gravity and/or to the adjacent segment. The central organization of posture involves interactions between external forces, the mechanical properties of the body and the neuromuscular forces.

Vestibular Evoked Potentials in Relapsing Paroxysmal Positional Vertigo

Paroxysmal positioning vertigo (PPV) is a major cause of vertigo accounting for 14 % of all equilibrium disorders with an annual incidence of about 100 per 100,000 of population [1]. It starts suddenly and is usually first noticed in bed, when waking from sleep. Any turn of the head seems to bring on violent but brief bursts of dizziness. Patients often describe the occurrence of vertigo with tilting of the head, looking up or down, or rolling over in bed. It is not unusual for nausea and vomiting to accompany the vertigo. Even if a spell is brief, a feeling of queasiness may last several minutes or even hours, and those who suffer from this kind of vertigo are distressed and incapacitated for several days severely impacting on social costs due to lost working days. PPV is a common vestibular disorder leading to significant morbidity, psychosocial impact, and medical costs. PPV accounted for 8 % of individuals with moderate or severe dizziness/vertigo. Is commonly accepted that PPV is due to displacement of otoconia and/or to vestibular macula/maculae lesion.