Posterior semicircular canal paroxysmal positional vertigo triggers a new type of windmill nystagmus.

BACKGROUND: Periodic alternating nystagmus is a rare condition characterised by spontaneous horizontal nystagmus that periodically reverses direction, indicating an alteration of the velocity storage mechanism. Windmill nystagmus is a peculiar and rare variant of periodic alternating horizontal nystagmus with a superimposed periodic alternating vertical nystagmus. It is generally observed in blind patients. CASE REPORT: This paper presents the unique case of a normally sighted patient with a windmill nystagmus triggered by an episode of benign paroxysmal positional vertigo due to bilateral posterior canalolithiasis. Videonystagmography revealed an anticlockwise up-beating nystagmus followed by a clockwise down-beating nystagmus with a cycle lasting 2 minutes, followed by a brief burst of horizontal left-beating nystagmus. CONCLUSION: This case report represents the first observation of a new type of windmill nystagmus, probably provoked by a malfunction of the velocity storage mechanism, gaze-stabilisation and short-adaptation networks, with a loss of cerebellar inhibition.

Facioscapulohumeral muscular dystrophy: hearing loss and other atypical features of patients with large 4q35 deletions.

BACKGROUND AND PURPOSE: Patients affected by facioscapulohumeral muscular dystrophy (FSHD) with unusual large 4q35 deletions tend to present atypical features in early childhood. We explored the clinical presentation of patients with a very short 4q35 fragment (10-13 kb) focusing on hearing loss, a still debated FSHD extra-muscular manifestation. PATIENTS AND METHODS: We evaluated six cases with EcoRI 4q35 fragment size ranging from 10 to 13 kb. Assessment of hearing function was carried out by otoscopy, audiometry and auditory-evoked brainstem responses (ABR). Patient data were compared with those of 28 similar subjects reported in the literature. RESULTS: Sensorineural hearing loss was found in four patients, who presented infantile-onset dystrophic phenotype. Hearing loss was associated with mental retardation in three of them and with epilepsy in two. Auditory ability of the other two cases was mildly impaired. If findings related to 28 similar cases reported to date are also considered, auditory impairment appears evident in 68% of these subjects. CONCLUSIONS: Hearing loss represents a characteristic feature of FSHD patients with a large 4q35 deletion. Moreover, when considering only cases with 10-11 kb, it appears to be associated with early-onset dystrophic phenotype, with mental retardation (92%) and possibly with epilepsy (58%).

Impaired auditory brainstem-evoked responses in insulin-dependent diabetic subjects.

Auditory brainstem-evoked responses (ABR) were recorded from the scalp of 30 normoacoustic insulin-dependent diabetic subjects, aged between 15 and 41 yr (29 +/- 7 yr). Three different stimulus repetition rates (11, 37, and 87 cps) were used. The results were compared with those obtained from 20 age- and sex-matched, normoacoustic control subjects. In diabetic patients, metabolic control (mean daily plasma glucose, glycosylated hemoglobin) and the presence of retinopathy, nephropathy, and somatic neuropathy were also investigated. The latencies (ms) of ABR waves were significantly impaired in diabetic subjects as compared with normals. Peripheral transmission time (wave I) and central transmission time (waves I-V) were also significantly delayed in diabetic subjects. Moreover, by increasing stimulus repetition rates, a significant increase in waves I-V shift was observed in diabetic patients. ABR impairment was not related to glucose balance, to the duration of diabetes, or to the presence of the diabetic retinopathy, nephropathy, and somatic neuropathy. In conclusion, diabetic neuropathy is characterized not only by somatic and autonomic nerve dysfunctions, but also by the early involvement of the central nervous system (CNS). ABR recording can represent a useful, noninvasive, simple procedure to detect both acoustic nerve and CNS damage.

Tumor outgrowth in peripheral blood mononuclear cell-injected SCID mice is not associated with early Epstein-Barr virus reactivation.

Epstein-Barr virus (EBV)-positive B-cell lymphoproliferative disease develops in severe combined immunodeficient (SCID) mice inoculated with peripheral blood mononuclear cells (PBMC) from EBV(+) individuals (SCID/hu mice). In this study, we investigated the contribution of EBV reactivation and de novo infection of B lymphocytes to tumor outgrowth in SCID/hu mice. Evaluation of BZLF-1, an early EBV activation transcript, in cells recovered from the mouse peritoneal cavity within 16 days following PBMC transfer did not reveal EBV reactivation, while BZLF-1 expression was only detected in tumor masses or in vitro established lymphoblastoid cell lines. To confirm these data by a different strategy, we coinjected PBMC from seropositive donors with purified B cells from seronegative donors of different sex. Fluorescence in situ hydridization analysis of the resulting tumor masses disclosed that the overwhelming majority of lymphoma cells originated from the seropositive donor, implying that no substantial in vivo production and transmission of virus had occurred. Further, treatment of SCID/hu mice with ganciclovir did not prevent lymphoma development. Our results suggest that in the SCID/hu mouse, early EBV replication and secondary infection of bystander B cells does not occur, and that the direct outgrowth of the transformed B lymphocytes present within the PBMC inoculum is the predominant mechanism, which leads to lymphoma generation in this experimental model.

Auditory brainstem evoked responses in the clinical evaluation and follow-up of insulin-dependent diabetic subjects.

In the last few years the use of ABR in the dysmetabolic encephalopathies has aroused considerable interest. Even though brainstem involvement in these syndromes is not yet entirely understood, ABR techniques have provided new and important insights. We studied 60 insulin-dependent diabetic subjects, 29 females and 31 males aged to 17 to 55 yrs, and observed ABR abnormalities in 28.2% of the cases. This impairment affects the I-V interval or central transmission time (CTT), which is considered the most reliable index of brainstem function. The ABR pattern was considered pathologic when the CTT was due 2DS as compared with a sex- and age-matched control. Follow-up studies performed on 20 of these subjects revealed no significant variation in the ABR tracing. This fact, together with the absence or correlation between ABR involvement and metabolic control and glycemia level during the test, could be attributed to a 'structural' damage of the brainstem tissue. In diabetics, we observed a significant correlation (p less than 0.05) between I-V interval shift and an EMG-proved reduction in motor conduction velocity (MCV) of the peroneal nerve. We also found a high incidence of ABR impairment (53%) in diabetics with cardiovascular autonomic failure.

Hemangiopericytoma of the skull base and Collet-Sicard syndrome: a case report.

Hemangiopericytoma (HP) is a mesenchymal tumor that originates from the pericytes of the capillary walls. This is a rare neoplasm, particularly in the head and neck; the skull base is involved exceptionally. We report a case of a large HP located in the jugular foramen. The last four cranial nerves were involved, causing a Collet-Sicard syndrome associated with facial palsy. Only one case of HP and Collet-Sicard syndrome is reported in the literature. The clinical course of the disease is described, emphasizing the long period of elapsed time between onset of the complaints and the final diagnosis. Diagnostic procedures and immunohistochemical evaluation are analyzed, along with the possible differential diagnosis with other pathological processes that more frequently involve the jugular foramen.

[Idiopathic cupulolithiasis: vasomotor reactivity evaluation of the vertebro-basilar artery by transcranial doppler ultrasonography and acetazolamide test]. / La cupulolitiasi idiopatica: studio della reattività vasomotoria del circolo vertebro-basilare con sonografia Doppler transcranica e test all'acetazolamide.

Benign paroxysmal positional vertigo (BPPV) or cupulolithiasis is one of the more common peripheral vestibular disorders. Diagnosis is made on the observation of typical positioning nystagmus brought about by the Hallpike manoeuver. In most cases of BPPV, etiology is unknown. Microcirculatory disorders have often been considered responsible for idiopathic BPPV. Few reports have been published on this specific aspect of the problem. In our study we evaluated vertebro-basilar haemodynamics and vasomotory reactivity after Acetazolamide administration in 12 patients with idiopathic BPPV. The results obtained reveal the absence of macrocirculatory impairment in the vertebro-basilar district in basal conditions, but significative vasoreactivity variation after acetazolamide, both in vertebral and basilar arteries. Poor vasomotor reactivity in one vertebral artery was observed in 5 patients and, in two cases, in the basilar artery. Altered vasoreactivity in the middle cerebral arteries was not observed in any case. In the light of these findings, we suggest that a possible inadequate response if microcirculation in the labyrinth, in some particular haemodynamic situations, might cause otolithic damage.

[Controversial aspects of magnetic resonance imaging in sudden onset cochleovestibular diseases]. / Aspetti controversi della risonanza magnetica nucleare nello studio delle cocleovestibolopatie improvvise.

Sudden deafness and vertigo are a challenge for the otolaryngologist. With its high fluid content, the membranous labyrinth is best evaluated through Magnetic Resonance Imaging (MRI). Recently gadolinium-enhanced MRI has opened new perspectives in the imaging of the pathological labyrinth, able to directly detect labyrinthine lesions. To date the main role of MRI has been to rule out the presence of retrocochlear involvement in patients with sudden deafness and/or vertigo. However, in the past few years, several authors, reporting on gadolinium-enhanced MRI, have described better labyrinthine imaging, revealing direct labyrinth or nerve bundle involvement in all such patients. On the contrary, other studies have not revealed any enhancement of post-contrast labyrinthine images upon MRI but have shown an increase in signal intensity upon T2-weighted images. In this light, the purpose of the present study has been a) to evaluate the prevalence of labyrinthine abnormalities found upon MRI in consecutive patients with sudden deafness and vertigo and b) to assess the correlation between the severity of clinical and audiological findings and the MRI abnormalities encountered. Twelve consecutive patients with sudden hearing loss and/or vertigo were included in the study (age range 9-59 years; 6 males and 6 females). All subjects underwent complete otoneurological examination. MRI was performed with a 0.5 T superconducting magnet system allowing 2 mm-thick sections through the temporal bone. Within 29 days of onset of the complaints all patients were studied both before and after administration of the contrast medium (gadolinium-DTPA, 0.01 mmol/l, i.v.). Two of the 12 subjects had sudden deafness, 5 sudden deafness and vertigo while 5 had vertigo alone. Gadolinium enhancement and/or a high signal intensity upon T2-weighted images of the pathological labyrinth and nerve bundle was observed in 4 patients. The patients were divided into groups by etiology. MRI abnormalities were only found in the group where the etiology was viral. There was no correlation between the severity of clinical findings and the presence of MRI abnormalities nor between MRI and ABR findings. Analysis of such controversial data is discussed, stressing the importance of gadolinium-enhanced MRI of the labyrinth as a new diagnostic tool in sudden deafness and vertigo.

[Transtympanic gentamicin in Ménière's disease: evaluation of the quality of life]. / La gentamicina transtimpanica nella malattia di Ménière. Valutazione della qualità di vita.

Different methods have been proposed for the management of intractable Ménière's disease. Over the past years a selection has been made based on the effectiveness and the side effects of the surgical techniques and only a few procedures are routinely used in modern practice. After a period of success, endolymphatic sac surgery is now being progressively abandoned in the aftermath of criticism on its real effectiveness. Vestibular neurectomy is considered an effective method for relieving vertigo but it is an invasive procedure and the risk of complications is not absent. Transtympanic gentamicin is now considered a real alternative approach to the treatment of vertigo in Ménière's disease. The literature reports a high incidence of success with this method, similar to that of vestibular neurectomy, and the only complication being some hearing loss encountered in a few cases. Strategies differ in the gentamicin treatment of Ménière's disease. In the past gentamicin was administered on a daily basis until an effect on the labyrinth was seen. Recently some authors have administered lower amounts of gentamicin for just two or there days. Such treatment appears to control vertigo equally well without causing labyrinthine areflexia although this is not supported in the literature by prolonged follow-ups. The authors discuss the results obtained with a low dosage transtympanic administration of gentamicin in a series of 29 patients followed up for two years. The impact of this form of therapy on quality of life was evaluated through a questionnaire prepared following the criteria of the American Academy of Otolaryngology Head and Neck Surgery. In all cases, the score improved at the end of follow-up.

[Value of TC99m-Nanocolloid spect in diagnosis and follow-up of necrotizing external otitis]. / La spect TC99m-nanocolloide nella diagnosi e follow up delle otiti esterne necrotizzanti.

Necrotizing external otitis (NEO), or malignant external otitis, a severe penetrating infection of the ear canal and the temporal bone, which occurs almost exclusively in diabetic or immunodepressed elderly patients, is caused in most cases by Pseudomonas aeruginosa while Staphylococcus epidermidis and Aspergillus fumigatus have been described as other possible agents. Recently bone scintigraphy, carried out above all employing SPECT, has been considered an important tool in diagnosis and follow-up of NEO. Many Authors confirm the role taken by Technetium99m-methylene-diphosphonate (MDP) and Gallium67-citrate bone scanning. Benecke suggested that response to therapy could be monitored with Ga67 or In111 scans. Two cases of NEO in which diagnosis and follow-up were made using Tc99m-nanocolloid (NC) SPECT are presented in this paper. The Authors discuss the advantages of this latter radiotracer, compared to those obtained with Ga67-citrate, in the follow-up evaluation of therapy efficacy. Tc99m-NC, in fact, is a better inflammation index in that its fixation on bone tissue is determined by the permeability of the basal membrane of vessels. Furthermore, with Tc99m-NC antibiotic therapy may be continued as long as necessary. Bone scintigraphy with other radiotracers may infact result positive for a long period after disease remission in that their fixation is linked to the one remodelling process.

Carotidynia: new aspects of a controversial entity.

Idiopathic carotidynia or Fay syndrome is a little known pathology, which in the past was the subject of much controversy. Even though carotydinia was removed as a pathological entity from the second International Headache Society classification in 2004, recent reports seem to confirm that the disease demonstrates unusual radiological findings. The presence of a typical amorphous enhancing soft tissue surrounding the carotid artery by MRI, CT and ultrasonography in patients with carotidynia has reopened discussion on the hypothesis that carotidynia may represent a distinctive inflammatory process. The aetiology of carotidynia is unknown. We report a case of carotidynia that developed after an upper airway infection, wherein MR studies demonstrated typical enhanced tissue surrounding the common carotid artery in contiguity with pathological enhancement in laryngeal tissue.

Auditory brainstem and middle latency evoked responses in the clinical evaluation of diabetes.

The measurement of auditory brainstem evoked responses and middle latency evoked responses may improve the evaluation of diabetic neuropathy. Twenty diabetic patients were studied (12 males, 8 females), aged 21 to 63 years with normal hearing, together with 20 age- and sex-matched normal subjects (10 males, 10 females). Auditory brainstem evoked responses were induced by rarefaction clicks of 0.1 ms at a repetition rate of 21.1 CPS and an intensity of 75 dB hearing level. Middle latency evoked responses were induced with clicks of 0.1 ms, a repetition rate of 7.7 CPS and an intensity of 75 dB hearing level. Diagnostic criteria were: a I-V interval latency shift greater than 2SD of the control group for the auditory brainstem evoked response test or the interval difference of wave V greater than 0.2 ms. Middle latency evoked response was diagnostic if the latency of the Pa component was greater than 2SD of normals. Twenty-five per cent of subjects had retrocochlear impairment (absence of I wave) even in the absence of symptoms. The combined technique of auditory brainstem evoked response and middle latency evoked response improved the detection rate of central nervous system dysfunction. Auditory brainstem response is important for detecting desynchronization of the auditory response, whereas middle latency evoked response detects abnormalities in the more rostral regions of the central nervous system. In conclusion, there is a role for auditory brainstem evoked response and middle latency evoked response in the global assessment of diabetic neuropathy.

Auditory evoked responses (ABR, MLR, SVR) and brain mapping in the elderly.

The influence of age on evoked auditory brainstem responses (ABRs) is still a matter of controversy. It is well known that in the elderly the ABRs show a progressive latency shift of the principal components. While many authors have reported a I-V internal latency shift, others claim that there is not a delay in the central conduction time (CCT) with ageing. Middle latency auditory evoked responses (MLRs) are also reported to be impaired in the elderly, but the few results published need further investigations. This study investigates some of the controversial aspects of electrophysiological assessment of the auditory system in the elderly. 36 healthy subjects (18 males and 18 females), mean age 67.2 years +/- 5.8, underwent ABRs, MLRs and SVRs and SVRs brain mapping evaluation. All the data were compared with our normative data for young adults. Our results confirm previous reports of a latency shift of all principal components of ABR, but do not demonstrate a significant CCT impairment in the elderly. The MLRs, SVRs and brain mapping analysis also support this conclusion.

Branchio-oto-renal dysplasia and branchio-oto dysplasia: report of eight new cases.

Eight new cases of "ear-pits-deafness syndrome" are reported here; in particular, the audiometric and tomographic findings of the ear and renal echography are discussed. Although it is difficult to give a nosologic definition of the syndrome, these cases can be classified as branchio-oto-renal dysplasia and branchio-oto dysplasia.

Topographic brain mapping of middle latency auditory evoked potentials in normal subjects.

Topographic brain mapping of auditory middle latency evoked responses (MLR) were obtained from 20 subjects (10 males and 10 females), all right-handed and with normal pure tone audiograms. Clicks with alternative polarity, with a rate of 7.7/sec. were delivered at an intensity of 75 dB HL monoaurally to both ears. Responses from 21 channels were amplified and band-pass filtered (3-150). All the surface maps were analyzed with a Bio-Logic Brain Atlas III system. MLR maps obtained show a quite small intrasubjective variability at the latencies of the principal components Na and Pa. The grand averages of MLR maps at the corresponding latencies in males and females were compared each other. All the entire temporal window has been segmented into some subepochs, showing similar spatial characteristics of the maps, like location of maxima and minima and, overall, shape.

MRI evidence of labyrinthine and eighth-nerve bundle involvement in mumps virus sudden deafness and vertigo.

Enhanced MRI has recently become an even more useful diagnostic tool in the study of the labyrinth in sudden deafness and vertigo. A 22-year-old male who experienced a right-sided sudden deafness and vertigo due to mumps virus underwent labyrinthine MRI examination with gadolinium, and both labyrinthine and nerve bundle involvement was demonstrated. The relationship between mumps virus and the sudden deafness in humans has not been completely established and the path of labyrinthine infection and the possible eighth-nerve involvement is discussed. In vivo evidence of labyrinthine and cochleovestibular-nerve involvement, in mumps virus sudden deafness and vertigo has not been previously demonstrated. MRI findings may represent a new contribution in the evaluation of the etiopathogenesis of mumps virus deafness and vertigo.

Menière's disease in congenital nephrogenic diabetes insipidus: report of two twins.

Two cases, twins, affected by congenital nephrogenic diabetes insipidus (CNDI) with a high daily volume of dilute urine excretion and periods of compensatory high levels of antidiuretic hormone (ADH) simultaneously developed a fluctuating Menière-type hearing loss. It is well known that the kidney and the cochlea are linked by structural and anatomic characteristics, as well as by the physiologic mechanism of electrolytes and fluid regulation. The patients herein described seem to be paradoxical, because they suffered from hydropic hearing loss despite the pathophysiologic mechanism of CNDI and the possible role played by ADH in water regulation in the inner ear. The consequences on Menière's disease of the different therapeutic regimens followed by the two CNDI patients are discussed. To our knowledge these are the first cases of CNDI with Menière's disease described in the literature.