The role of vestibular cold caloric tests in the presence of spontaneous nystagmus

Objective. The bithermal caloric test is commonly used to detect a canal paresis. However, in case of spontaneous nystagmus, this procedure can provide results of non-univocal inter-pretation. On the other hand, confirming the presence of a unilateral vestibular deficit can help to differentiate between central and a peripheral vestibular involvement.Methods. We studied 78 patients suffering from acute vertigo and showing spontaneous horizontal unidirectional nystagmus. All patients were submitted to bithermal caloric tests, and the results were compared with those obtained using a monothermal (cold) caloric test.Results. We demonstrate the congruence between the bithermal and monothermal (cold) caloric test through mathematical analysis of the results of both tests in patients with acute vertigo and spontaneous nystagmus.Conclusions. We propose to perform the caloric test in the presence of a spontaneous nys-tagmus using a monothermal cold assuming that the prevalence of the response to the cold irrigation on the side towards which the nystagmus beats is a sign of the presence of patho-logical unilateral weakness and therefore more likely peripheral in its origin

"The Pupillary (Hippus) Nystagmus": A Possible Clinical Hallmark to Support the Diagnosis of Vestibular Migraine

(1) Background: Hippus (which in this paper will be called "Pupillary nystagmus") is a well-known phenomenon which has never been related to any specific pathology, so much so that it can be considered physiological even in the normal subject, and is characterized by cycles of dilation and narrowing of the pupil under constant lighting conditions. The aim of this study is to verify the presence of pupillary nystagmus in a series of patients suffering from vestibular migraine. (2) Methods: 30 patients with dizziness suffering from vestibular migraine (VM), diagnosed according to the international criteria, were evaluated for the presence of pupillary nystagmus and compared with the results obtained in a group of 50 patients complaining of dizziness that was not migraine-related. (3) Results: Among the 30 VM patients, only two cases were found to be negative for pupillary nystagmus. Among the 50 non-migraineurs dizzy patients, three had pupillary nystagmus, while the remaining 47 did not. This resulted in a test sensitivity of 0.93% and a specificity of 0.94%. (4) Conclusion: we propose the consideration of the presence of pupillary nystagmus as an objective sign (present in the inter-critical phase) to be associated with the international diagnostic criteria for the diagnosis of vestibular migraine

Recurring benign paroxysmal positional vertigo after successful canalith repositioning manoeuvers

Benign baroxysmal positional vertigo (BPPV) represents the most common peripheral vestibular dysfunction encountered in clinical practice. Although canalith repositioning procedures (CRPs) are a relatively successful treatment for BPPV, many patients suffer from recurrences. Several studies have demonstrated that various pathological conditions (diabetes, hypertension, endolymphatic hydrops, low vitamin D levels) as well as delayed BPPV treatment using CRP, multiple canal involvement may be associated with recurrence of BPPV. We evaluated the history of 1,428 patients (558 males and 870 females, age range 10-92 years) suffering from BPPV. Of 1,428 cases, 820 (77%) did not relapse in the following 20 years. Mean age and gender did not differ significantly between groups with and without recurrence. Regarding risk factors for BPPV recurrence, age, female gender, migraine, hypertension, diabetes mellitus, hyperlipidaemia, osteoporosis, vascular diseases, and vitamin D deficiency may be associated with recurrent BPPV and should be kept in mind. Osteoporosis, vitamin D deficiency as well as thyroid dysfunction should be evaluated in postmenopausal women. Treatment of these comorbidities may help to reduce the risk of BPPV recurrence

IMPLEMENTAZIONE IN TECNOLOGIA SOFTWARE-DEFINED RADIO DI UN TRASMETTITORE TETRA/DMO SU FRAMEWORK SCA-COMPLIANT

In this work I study development and implementation of a TETRA/DMO transmitter on Software Defined Radio technology. In particular each component of the transmission chain has been developed in C++ using framework Sca-compliant, such as OSSIE. Waveform has been validated by means to several tests, employing measurement instruments and other laboratory tools

Uphill/downhill nystagmus

Capita spesso che un paziente con vertigini sia difficilmente inquadrabile (se periferico o centrale), anche affidandosi ai criteri consigliati nella recente letteratura. In questo lavoro si propone di utilizzare la valutazione della combinazione tra nistagmo spontaneo ed Ocular Tilt Reaction per dare un giudizio sulla sede della patologia che provoca il nistagmo. Si propone di dividere il nistagmo in : 1) nistagmo in salita in cui il nistagmo batte su un piano inclinato e il verso della fase rapida è verso locchio ipertropico (questo tipo di nistagmo è verosimilmente periferico); 2) nistagmo in discesa in cui il nistagmo batte verso locchio ipotropico (questo tipo di nistagmo è verosimilmente centrale); 3) nistagmo in piano in cui il piano su cui batte il nistagmo è perfettamente orizzontale e sul quale non si può dire nulla (è stato rilevato solo nel 15% dei casi). La posizione nello spazio del vettore del nistagmo è da considerare una caratteristica intrinseca del nistagmo stesso (come direzione, verso ,frequenza, velocità angolare ecc.) e va riportata nella descrizione del nistagmo, potendo dare unindicazione sulla sua natura (periferico o centrale). In particolare, confrontando linclinazione del nistagmo con lHead Impulse Test (HIT), si ottengono risultati simili nella valutazione topodiagnostica di un nistagmo spontaneo. Sembra dunque che questo segno possa confermare lHIT per una diagnosi più sicura o sostituirlo in casi dubbi. Al contrario, in caso di nistagmo che batte in piano (né in salita né in discesa, attribuibile probabilmente al fatto che le macule utriculari sono risparmiate) lHIT può sostituire losservazione del piano del nistagmo. In questo modo i due segni si confermano e si integrano a vicenda nei casi dubbi. Il test non richiede tempi aggiuntivi e non è in alcun modo causa di disturbo per il paziente, per cui se ne propone linserimento nella valutazione di ogni nistagmo spontaneo

Episodic Vertigo: A Narrative Review Based on a Single-Center Clinical Experience

: (1) Background: Usually, the majority of patients suffering from vertigo and dizziness can be identified in four major categories: acute spontaneous vertigo, episodic (recurrent) vertigo, recurrent positional vertigo, and chronic imbalance. Our purpose is to retrospectively evaluate the main causes of episodic vertigo and to find indications for a reliable clinical suspicion useful for a definitive diagnosis, comparing patients affected by different presenting symptomatology (acute vertigo, recurrent episodic vertigo, and imbalance). (2) Methods: we retrospectively evaluated the clinical records in a population of 249 consecutive patients observed for vertigo in our tertiary referral center in the period 1 January 2019-31 January 2020. On the basis of the reported clinical history, patients were divided into three groups: patients with their first ever attack of vertigo, patients with recurrent vertigo and dizziness, and patients with chronic imbalance. (3) Results: On the basis of the results of the instrumental examination, we arbitrarily divided (for each type of symptoms) the patients in a group with a normal vestibular instrumental examination and a group of patients in which the clinical-instrumental evaluation showed some pathological results; a highly significant difference (p: 0.157) was found between recurrent and acute vertigo and between recurrent vertigo and imbalance. (4) Conclusions: Patients with recurrent vertigo more frequently exhibit a negative otoneurological examination since they are often examined in the intercritical phase. A precise and in-depth research of the patient's clinical history is the key to suspect or make a diagnosis together with the search for some instrumental or clinical hallmark, especially in cases where the clinical picture does not fully meet the international diagnostic criteria

Analysis of the Skew Deviation to Evaluate the Period of Onset of a Canalolithiasis After Macular Damage

Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular end-organ disease, and it is one of the first causes of access to the emergency room. The moment of migration of the otoconial debris in a semicircular canal does not necessarily coincide with the moment of detachment of the debris themselves. Consequently, the paroxysmal positional vertigo could arise with a variable delay with respect to the mechanical damage suffered by the macula. The aim of this work is to try to identify objective criteria to establish whether a canalolithiasis is synchronous or diachronic to the damage. The analysis of skew deviation in the context of ocular tilt reaction in patients with canalolithiasis could provide useful information to understand if macular damage occurred at the origin of the disease and when the damage may have occurred. In this study, 38 patients with BPPV were analyzed based on the type of skew deviation that was presented. We found that if the eye on the side of the canalolithiasis is hypotropic the damage of the utriculus is likely recent (last 10 days), if it is hypertropic the damage is not recent (20 days before) and finally if the eyes are at the same height it could be an utricular damage in compensation (occurring the last 10-20 days) or a secondary labyrinth canalolithiasis, without associated utricular damage. Our results show that the evaluation of skew deviation in patients suffering from BPPV could be useful to evaluate: (a) if a positional paroxysmal nystagmus can be related to an previous relevant injury event (for example a head injury that occurred days before the crisis); (b) if it is a BPPV of recent onset or a re-entry of the debris into the canal