Audiovestibular Findings in Patients with Concurrent Superior Canal Dehiscence and Vestibular Schwannoma

OBJECTIVE

To describe the clinical-instrumental findings in case of concurrent superior canal dehiscence (SCD) and ipsilateral vestibular schwannoma (VS), aiming to highlight the importance of an extensive instrumental assessment to achieve a correct diagnosis.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Five patients with concurrent SCD and VS.

INTERVENTION

Clinical-instrumental assessment and imaging.

MAIN OUTCOME MEASURE

Clinical presentation, audiovestibular findings, and imaging.

RESULTS

The chief complaints were hearing loss (HL) and unsteadiness (80%). Other main symptoms included tinnitus (60%) and pressure-induced vertigo (40%). Mixed-HL was identified in three patients and pure sensorineural-HL in 1, including a roll-over curve in speech-audiometry in two cases. Vibration-induced nystagmus was elicited in all cases, whereas vestibular-evoked myogenic potentials showed reduced thresholds and enhanced amplitudes on the affected side in three patients. Ipsilesional weakness on caloric testing was detected in three patients and a bilateral hyporeflexia in one. A global canal impairment was detected by the video-head impulse test in one case, whereas the rest of the cohort exhibited a reduced function for the affected superior canal, together with ipsilateral posterior canal impairment in two cases. All patients performed both temporal bones HRCT scan and brain-MRI showing unilateral SCD and ipsilateral VS, respectively. All patients were submitted to a wait-and-scan approach, requiring VS removal only in one case.

CONCLUSION

Simultaneous SCD and VS might result in subtle clinical presentation with puzzling lesion patterns. When unclear symptoms and signs occur, a complete audiovestibular assessment plays a key role to address imaging and diagnosis.

A Bilateral Vestibular Schwannoma is Not Always Related to Neurofibromatosis Type 2

Bilateral vestibular schwannomas are commonly diagnosed in patients affected by neurofibromatosis type 2, a genetic disease caused by a heterozygous mutation in the gene region encoding neurofibromin-2. Sporadic bilateral vestibular schwannomas are very rare entities affecting almost exclusively elderly people. We present the case of a senior woman who was followed up with the "wait-and-scan" strategy for a unilateral vestibular schwannoma that later developed as a contralateral tumor, compatible with vestibular schwannoma, raising questions about its nature and risk of having been transmitted in offspring. Genetic testing excluded mutations of the neurofibromatosis type 2 gene. The presence of bilateral vestibular schwannomas is often considered pathognomonic of neurofibromatosis type 2, but the estimated probability of sporadic bilateral tumors in the absence of other neurofibromatosis type 2 features is 50% over 70 years of age. Therefore, the NF2 gene assessment is in any case recommended in these patients not only for an evaluation of the risk of being transmitted. The treatment strategy should be carefully personalized for each patient, considering the size of the tumors, symptoms, and hearing function together with the patient's age.

Evidence-based surveillance protocol for vestibular schwannomas: a long-term analysis of tumor growth using conditional probability

OBJECTIVE

The growth characteristics of vestibular schwannomas (VSs) under surveillance can be studied using a Bayesian method of growth risk stratification by time after surveillance onset, allowing dynamic evaluations of growth risks. There is no consensus on the optimum surveillance strategy in terms of frequency and duration, particularly for long-term growth risks. In this study, the long-term conditional probability of new VS growth was reported for patients after 5 years of demonstrated nongrowth. This allowed modeling of long-term VS growth risks, the creation of an evidence-based surveillance protocol, and the proposal of a cost-benefit analysis decision aid.

METHODS

The authors performed an international multicenter retrospective analysis of prospectively collected databases from five tertiary care referral skull base units. Patients diagnosed with sporadic unilateral VS between 1990 and 2010 who had a minimum of 10 years of surveillance MRI showing VS nongrowth in the first 5 years of follow-up were included in the analysis. Conditional probabilities of growth were calculated according to Bayes' theorem, and nonlinear regression analyses allowed modeling of growth. A cost-benefit analysis was also performed.

RESULTS

A total of 354 patients were included in the study. Across the surveillance period from 6 to 10 years postdiagnosis, a total of 12 tumors were seen to grow (3.4%). There was no significant difference in long-term growth risk for intracanalicular versus extracanalicular VSs (p = 0.41). At 6 years, the residual conditional probability of growth from this point onward was seen to be 2.28% (95% CI 0.70%-5.44%); at 7 years, 1.35% (95% CI 0.25%-4.10%); at 8 years, 0.80% (95% CI 0.07%-3.25%); at 9 years, 0.47% (95% CI 0.01%-2.71%); and at 10 years, 0.28% (95% CI 0.00%-2.37%). Modeling determined that the remaining lifetime risk of growth would be less than 1% at 7 years 7 months, less than 0.5% at 8 years 11 months, and less than 0.25% at 10 years 4 months.

CONCLUSIONS

This multicenter study evaluates the conditional probability of VS growth in patients with long-term VS surveillance (6-10 years). On the basis of these growth risks, the authors posited a surveillance protocol with imaging at 6 months (t = 0.5), annually for 3 years (t = 1.5, 2.5, 3.5), twice at 2-year intervals (t = 5.5, 7.5), and a final scan after 3 years (t = 10.5). This can be used to better inform patients of their risk of growth at particular points along their surveillance timeline, balancing the risk of missing late growth with the costs of repeated imaging. A cost-benefit analysis decision aid was also proposed to allow units to make their own decisions regarding the cessation of surveillance.

Early experience in tracheostomy and tracheostomy tube management in Covid-19 patients

In Italy, we have experienced Europe's first and largest coronavirus outbreak. Based on our preliminary experience, we discuss the challenges in performing tracheotomy and tracheostoma care in the setting of a new pathogen.

The effect of superior canal dehiscence size and location on audiometric measurements, vestibular-evoked myogenic potentials and video-head impulse testing

PURPOSE

To correlate objective measures of audio-vestibular function with superior canal dehiscence (SCD) size and location in ears with SCD and compare results with literature.

METHODS

We retrospectively evaluated 242 patients exhibiting SCD and/or extremely thinned bone overlying superior canals (SC) on CT scans and selected 73 SCD patients (95 ears with SCD). Data concerning audiometry, impedance audiometry, video-head impulse test (vHIT), cervical vestibular-evoked myogenic potentials (cVEMPs) and ocular VEMPs (oVEMPs) to air- (AC) and bone-conducted (BC) stimuli were collected for each pathologic ear and correlated with dehiscence size and location.

RESULTS

AC pure-tone average (PTA) (p = 0.013), low-frequency air-bone gap (ABG) (p  < 0.001), AC cVEMPs amplitude (p = 0.002), BC cVEMPs amplitude (p < 0.001) and both AC and BC oVEMPs amplitude (p < 0.001) positively correlated with increasing SCD size. An inverse relationship between dehiscence length and both AC cVEMPs and oVEMPs thresholds (p < 0.001) and SC vestibulo-ocular reflex (VOR) gain (p < 0.001) was observed. Dehiscences at the arcuate eminence (AE) exhibited lower SC VOR gains compared to SCD along the ampullary arm (p = 0.008) and less impaired BC thresholds than dehiscences at the superior petrosal sinus (p = 0.04).

CONCLUSION

We confirmed that SCD size affects AC PTA, ABG and both amplitudes and thresholds of cVEMPs and oVEMPs. We also described a tendency for SC function to impair with increasing SCD size and when dehiscence is located at the AE. The latter data may be explained either by a spontaneous canal plugging exerted by middle fossa dura or by a dissipation through the dehiscence of mechanical energy conveyed to the endolymph during high-frequency impulses.

Two Different Extranodal Lymphomas in an HIV+ Patient: A Case Report and Review of the Literature

Human immune deficiency virus- (HIV-) infected individuals present a higher risk of developing malignancies. Herein, we are presenting an unusual case of an untreated HIV+ patient, who developed two distinct lymphoproliferative disorders in a period of 4 years: a primary cutaneous T-cell lymphoma (PCTCL) and a diffuse large B-cell lymphoma (DLBCL) not otherwise specified (NOS), the latter developed while commencing combined antiretroviral therapy (cART). The two lymphomas also showed peculiar features: PCTCL are rarely described in HIV+ setting and particularly at such a low clinical stage, and the DLBCL showed uncommon cytology, non-GCB phenotype, EBER negativity, and absence of c-MYC translocation, all atypical features in this clinical context. This report not only confirms the increased risk of lymphoma for HIV+ patients and HIV infection being one of the major risk factors for lymphoid disorders but draws the attention on the possible occurrence of unusual features, suggesting that HIV serology should always be investigated in the clinical suspicion of lymphoma.

Isolated horizontal canal hypofunction differentiating a canalith jam from an acute peripheral vestibular loss

OBJECTIVES

To describe a unique case of acute vertigo presenting with spontaneous horizontal nystagmus (SHN) and a clinical picture consistent with right acute peripheral vestibular loss (APVL) in which an isolated hypofunction of a horizontal semicircular canal (HSC) permitted to detect a spontaneous canalith jam and treat the patient accordingly.

METHODS

Case report and literature review.

RESULTS

A 74-year old woman presented with acute vertigo, left-beating SHN and a clinical picture consistent with right APVL. Nevertheless, vestibular evoked myogenic potentials were normal with symmetrical amplitudes and the video head impulse test (vHIT) revealed an isolated hypofunction of the right HSC. After repeated head shakings, the supine roll test evoked bilaterally a positioning paroxysmal geotropic horizontal nystagmus suggesting benign paroxysmal positional vertigo involving the non-ampullated arm of the right HSC. vHIT and caloric testing confirmed restitution of HSC function after repositioning maneuvers.

CONCLUSIONS

In case of acute vertigo with SHN, a complete functional assessment of vestibular receptors and afferents should always be given in order to avoid misdiagnosis. Canalith jam should be considered in case of spontaneous nystagmus and isolated canal hypofunction.

Superior canal dehiscence with tegmen defect revealed by otoscopy: Video clip demonstration of pulsatile tympanic membrane

Superior canal dehiscence is a pathologic condition of the otic capsule acting as aberrant window of the inner ear. It results in reduction of inner ear impedance and in abnormal exposure of the labyrinthine neuroepithelium to the action of the surrounding structures. The sum of these phenomena leads to the onset of typical cochleo-vestibular symptoms and signs. Among them, pulsatile tinnitus has been attributed to a direct transmission of intracranial vascular activities to labyrinthine fluids. We present the first video-otoscopic documentation of spontaneous pulse-synchronous movements of the tympanic membrane in two patients with superior canal dehiscence. Pulsating eardrum may represent an additional sign of third-mobile window lesion.

Could statins exert a protective effect on epistaxis of systemic origin?

Epistaxis, that is a relatively frequent occurrence of hemorrhage from the nose, is reported in up to 60% of the population with peak incidences in subjects under the age of ten ("essential" epistaxis, usually linked to an altered vasomotor regulation) and, with even greater entity, over the age of 60. The cause of nosebleeds can generally be divided into two categories, local and systemic factors, although it should be remembered that a significant number of nosebleeds occur with no obvious cause. Actually, according to the common observation the epistaxis prone subject is an elderly with hypertension associated to some degree of vascular alteration. The statins essentially exert a competitive inhibition of 3-hydroxy-3 methyl glutaryl coenzyme A (HMG-CoA) reductase that results in cholesterol synthesis inhibition. In the last years, however, there has been a growing evidence that these drugs exert a number of vascular actions that are independent of lipid lowering and result in a vasoprotective effect. Due to their favourable influence on the vascular wall, and the consequent possible modulatory effect on blood pressure, a possible utility of statins in preventing many cases of nosebleed is hypothesized, to our knowledge for the first time.

Early management of hearing and balance disorders: a review of literature and a proposal to overcome possible uncertainties

The lack of a correct diagnostic and therapeutic planning of vestibular diseases is still often observed, and some difficulties are still to deal with in clinical practice, even when treating acute hearing problems, although the needed competence is more easily identified as otologic. A review of the international literature confirms the existence of such a problem, and permits to underline the scarcity of connections between otology and neurotology, on one hand, and principles of basic sciences and general and internal medicine, on the other hand: this can explain some therapeutic contradictions in treating inner ear disorders, their frequent labelling as idiopathic and the persisting uncertainties concerning a correct diagnostic and therapeutic management. In order to overcome the difficulties deriving to insufficient interdisciplinary cooperation, the institution of hospital audiovestibular services with a strictly linked net of cooperation with internal medicine units could represent a progress. This could help prevent clinically and economically inadequate management, contributing to minimize the possibility of expensive and/or health-threatening mistakes; moreover, it could represent an example to easily improve the practical aspects of both pre graduate and postgraduate curricula, and to form more open-minded clinicians, starting both from an ear. Nose and throat (ENT)/audiological and from an Internal Medicine extraction.

Meniere's disease and the use of proton pump inhibitors

PRINCIPLES

On the basis of previous observations we examined the possibility of a favourable effect of proton pump inhibitors (PPI) on Meniere's disease (MD). A preliminary step was made by retrospectively analysing the number of menieric crisis in group of patients suffering from MD and using PPI for other reasons as compared to a group of menieric subjects who had never used PPI.

METHODS

Between January 2001 and December 2006, 42 patients affected by MD were examined in the tertiary referral centre at the University Hospital of Bologna, Italy and in the private office of an ENT specialist in Cassino, Italy. Within the study group, 18 patients had used PPI for various reasons for at least 12 consecutive months, whilst 24 patients had never been prescribed them. We recorded the number of menieric crises reported in the observation period. The mean follow-up period was 21.9 months. Statistical analysis was performed by means of the x2 test and significance was defined when p<0.05.

RESULTS

Most of MD patients (72%) using PPI suffered less than one episode of menieric crisis/year. On the other hand patients who had never used a PPI, experienced considerably more episodes only 16.7% having less than one crisis per year. This difference was statistically significant (p<0, 001).

CONCLUSIONS

Even taking the limitations of this retrospective study into account the reported data nevertheless strongly suggest a possible role for proton pumps in the pathogenesis of MD. This could lead to interesting developments and contribute to a better definition of MD and the therapeutic possibilities.

Langerhans cell histiocytosis: bilateral temporal bone involvement in an adult with diabetes insipidus

OBJECTIVE

To present a clinical case of an adult affected by Langerhans cell histiocytosis with bilateral, non-simultaneous, involvement of the temporal bone, associated with diabetes insipidus and to review the literature.

METHODOLOGY

A rare case of bilateral temporal bone involvement of Langerhans cell histiocytosis in a 42-year-old woman affected by diabetes insipidus is reported. We present patient's clinical history supported by radiologic, histopathologic and audiologic findings.

RESULTS

The patient was submitted to a series of otologic surgical procedures due to the progression of the disease. Ossicular chain was always preserved, so that conservative surgery (canal wall-up technique) was performed, permitting the achievement of good hearing results, bilaterally.

CONCLUSIONS

Temporal bone involvement of Langerhans cell histiocytosis may lead to a progressive chronic disease. However, the ossicular chain can remain uninvolved, making a conservative surgical treatment possible. Careful follow-up is essential for detecting new lesions and serial CT scans are mandatory.

Otoscopic findings in hypercholesterolemic subjects

OBJECTIVES

We aimed to verify the extent of a previously cited relationship between tympanosclerosis and atherosclerosis by investigating subjects with dysfunction in lipid metabolism but no clinically apparent symptoms of atherosclerotic disease.

METHODOLOGY

Forty hypercholesterolemic patients were submitted to Doppler ultrasound examination of carotid and vertebrobasilar arterial regions; results were matched to otoscopic findings. Otoscopy was performed to evaluate for sclerotic plaques of the tympanic membrane, which represent the most common, clinically non-relevant manifestation of tympanosclerosis. A control group of 41 randomly chosen healthy subjects were also included.

RESULTS

Nine (22.5%) of 40 subjects with hypercholesterolemia showed tympanic sclerotic plaques at otoscopy compared to 2 (4.9%) out of 41 control patients. This difference was statistically significant (p = 0.02). An even stronger association (p = 0.01) was found between tympanic and arterial plaques in the study group, as we identified tympanic sclerotic plaques in 7 (41.2%) out of 17 patients with positive Doppler ultrasound signals for arterial plaques. Only two (8.7%) out of 23 subjects without plaques on Doppler ultrasound examination had tympanic sclerotic plaques.

CONCLUSIONS

The results of this study confirm the existence of a link between tympanosclerosis and atherosclerosis. To our knowledge, this is the first report of a link between these findings in preclinical atherosclerotic conditions.

Tinnitus as a warning for preventing vasovagal syncope

It has been widely outlined by our group the possibility that a sufferance of the inner ear can take place as a consequence of hemodynamic imbalance which could affect young and healthy people and recognize a merely functional origin. As reported in previous papers, an altered reaction of the autonomic nervous system could actually jeopardize the labyrinthine perfusion even in absence of other damages. From this standpoint, the hypothesis that a hyperactivity of the vagal response to an acute sympathetic drive may result in an inner ear sufferance deserves to be explored. A mechanism which appears to fit to this model is represented by the Bezold-Jarisch reflex (BJR), which is considered to be responsible for vasovagal syncope and is characterized by a dynamic reasonably compatible with our findings. According to these premises, especially considering that the inner ear has a less active protective mechanism against ischemia as compared to brain, in predisposed subjects tinnitus, when considered as an initial symptom of inner ear hypoperfusion, can represent a warning able to prevent the lack of consciousness related to the syncope.

Hearing loss in vestibular schwannomas: analysis of cochlear function by means of distortion-product otoacoustic emissions

OBJECTIVE

We investigated cochlear function in a group of patients affected by vestibular schwannoma (VS), by means of recording distortion-product otoacoustic emissions (DPOAEs).

METHODS

Between January 1996 and January 2007, we observed 183 patients affected by unilateral VS. DPOAEs, compared to the corresponding hearing thresholds, were subjectively classified into three categories: "compatible" with hearing function, "cochlear" and "retro-cochlear". We also related the responses to some clinical variables (tumor size, intracanalicular tumor and radiologic appearance of the internal auditory canal). Statistical analysis was performed.

RESULTS

In 137 cases (74.9%), DPOAEs were as expected based on audiometry responses, while in 11 patients (6%) a "cochlear" DP-gram was recorded and in 35 patients (19.1%) DPOAEs evidenced a "retro-cochlear" pattern. In eight cases we detected acoustic responses despite a profound hearing loss. No statistically significant data merged from the comparison between "cochlear" and "retro-cochlear" responses and the clinical variables.

CONCLUSION

Our results confirm that sensorineural hearing loss due to VS can be of sensory and/or neural origin. DPOAEs still remain just a complementary auditory test; nevertheless, in case of severe or profound unilateral hearing loss, recorded acoustic responses may be suspicious for the presence of a vestibular schwannoma.

Secretory meningioma of the middle ear: a light microscopic, immunohistochemical and ultrastructural study of one case

A 66-year-old woman was referred with left hearing loss. A probable diagnosis of left secretory otitis media with effusion was formulated. A left myringotomy was performed to remove hyperplastic hard tissue from the tympanic cavity. A high resolution CT scan of the temporal bone disclosed a soft-tissue mass completely involving the mastoid and tympanic cavity, surrounding the ossicular chain which appeared spared with no signs of infiltration. The histopathologic, immunohistochemical and ultrastructural response was secretory meningioma, a rare variant of conventional meningothelial meningioma in atypical sites.

Hypotension as an isolated factor may not be sufficient to provoke hearing impairment

OBJECTIVE

We investigated the possible role of hypotension and related autonomic phenomena in the pathogenic mechanism of sudden sensorineural hearing loss.

METHODS

Forty-nine patients belonging to the ASA I-II classes of anaesthesiological risk and submitted to a non-otological surgical procedure were examined. Each operation was performed under general anaesthesia by controlled hypotension technique. Hearing function of the patients was evaluated before and after surgery by means of a pure tone audiometry recorded by the same clinician with the same instrument.

RESULTS

No cases of bilateral hearing worsening were recorded after surgery.

CONCLUSIONS

An induced and controlled steady hypotension under general anaesthesia did not affect the hearing function of any of the patients. It may be supposed, therefore, that an adverse effect on the cochlear oxygenation is more likely to be caused by the sympathetic changes induced by a consistent decrease of blood pressure rather than to hypotension itself.

Possible relationship between tympanosclerosis and atherosclerosis

OBJECTIVE

In order to confirm a possible link, as suggested by a recent study, between atherosclerosis and tympanosclerosis, and which could theoretically open new frontiers in the early diagnosis of vascular atherosclerotic diseases starting from a rather simple and rapid examination such as otoscopy, we further investigated this hypothesis in a population affected by atherosclerotic disease of the carotid artery.

MATERIAL AND METHODS

Fifty patients submitted to carotid endarterectomy were examined. Patients with a history of previous otologic diseases or otosurgical procedures were excluded. The presence of tympanosclerosis was defined if at least 20% of the eardrum was affected by tympanic plaques. The study group was compared to a sex- and age-matched control group randomly chosen from our hospital with a negative history of vascular and otologic diseases.

RESULTS

Tympanosclerosis was observed in 18/50 patients (36%) in the study group, compared to 6/50 cases in the control group (12%). This difference was statistically significant (p = 0.005). In both groups the incidence of this finding was similar for both sexes.

CONCLUSIONS

Our results confirm the reported analogies between tympanosclerosis and atherosclerosis. Although further investigations are needed, promising implications can be predicted for the diagnostic and therapeutic evaluation of this kind of ear patient.

Is carotid stenosis correlated with tympanosclerosis

AIM

Tympanosclerosis and atherosclerosis seem to have a similar inflammatory origin despite the different tissues involved. We have investigated the possible relationship between tympanosclerosis and atherosclerosis by evaluating the incidence of tympanic plaques in patients with significant carotid disease.

METHODS

Between September 1(st) 2002 and April 30th 2003, we have evaluated all patients undergoing carotid surgery for significant carotid stenosis (group A). If at least 1/5 of the eardrum was occupied by plaques, then the case was considered positive. A control group of patients of similar age and no history of otological nor vascular pathologies was enrolled (group B). The 2 groups were compared statistically by Fisher's test and significance was set at p=0.05.

RESULTS

Group A consisted of 84 patients. In this group 32 patients (38.1%) had tympanosclerosis; it was bilateral in 12 cases. Group B had 84 patients. In this group tympanosclerosis was present in 11 cases (13%). The difference between the 2 groups was statistically significant (p=0.005).

CONCLUSION

More studies are needed before we can understand the cause of the association between these 2 pathologies. However early screening of atherosclerotic disease in patients with tympanosclerosis seems justifiable on the basis of the data of both the literature and the present study.

[Cisplatin and carboplatin-induced ototoxicity in children: clinical aspects and perspectives for prevention]

In 70% of the cases of malignant neoplasms in pediatric patients antiblast therapy is used. The administration of platinum compounds, Cisplatin (CDDP) or Carboplatin (CBDCA), often at high cumulative doses, necessarily implies a certain degree of toxicity which normally takes on secondary significance in the healing of the child. Among the side effects, early and delayed ototoxicity is well known and, in the child, take on particular aspects. While not abandoning the treatment of the base pathology, the therapeutic findings, increasingly comforting in terms of long-term survival, require more accurate evaluation and overall control of the quality of life of these young patients. Since initial cochlear damage can be reversible, auditory function must be carefully monitored in order to prevent the lesions from becoming permanent, in particular prior to the onset of speech. For this reason a retrospective study was made of a group of 26 children affected by malignant neoplasms all of whom had undergone a polychemotherapy protocol with the administration of CDDP in 14 cases and CBDCA in 12 cases. All these young patients were monitored with conventional audiometry. The presence of different variables (antiblastic drug administration schedule, course of the disease, general conditions) only permitted evaluation of a single correlation: between auditory function at the end of the treatment (or after a few cycles of therapy) and the overall dose of CDDP or CBDCA administered. In 16 cases (62%) typical bilateral perceptive deafness was detected progressively involving the hyperacute and acute frequencies. The finding of hearing loss was significantly greater in the patients treated with CDDP (86%) vs. those treated with CBDCA (33%). Moreover, analysis of the results showed that, within certain limits, ototoxicity can depend more on individual sensitivity to the drug than to the total dose administered. The results confirm the well-known ototoxicity of platinum compounds, in particular CDDP. As ever improved therapeutic results are achieved in the treatment of malignant neoplasms in pediatric patients, greater attention can be paid to the quality of life of these young patients after the disease has been healed. Careful monitoring of auditory function can be extremely important in the pursuit this objective; indeed, this makes it possible to adjust antiblast drug administration, particularly in the later stages of treatment, customizing the treatment schedule to individual patient sensitivity.

Systemic hypotension and the development of acute sensorineural hearing loss in young healthy subjects

BACKGROUND

Sudden sensorineural hearing loss (SSHL) is an acute disorder whose origin is often unclear. A vascular disorder may be a causative factor.

OBJECTIVE

To determine whether hypotension influences the genesis of SSHL in healthy subjects.

DESIGN

To investigate the role of a 24-hour blood pressure (BP) profile in a population of young subjects with SSHL from January 1, 1996, to December 31, 1999, by a nonrandomized controlled trial.

SETTING

The Ear, Nose and Throat Section of the Department of Surgical and Anaesthesiological Sciences and the Department of Internal Medicine, S. Orsola Hospital, University of Bologna, Bologna, Italy.

PATIENTS

The study population consisted of 23 untreated healthy patients diagnosed as having SSHL compared with 20 age- and sex-matched normotensive control subjects. Both groups underwent 24-hour BP monitoring, and their BP profiles were analyzed and compared with routine BP values. The data were analyzed with the Statistical Package for the Social Sciences, version 7.1, and the results are expressed as mean +/- SD.

MAIN OUTCOME MEASURES

The mean BP values were expected to be lower in the study population.

RESULTS

The average clinic and ambulatory BP values were significantly lower in patients with SSHL, for systolic (clinic, P =.004; ambulatory BP, P =.02) and diastolic (clinic, P =.03; ambulatory BP, P =.03) values. The occurrence of persistent hypotension (the presence of >2 consecutive recordings of systolic BP of < or =105 mm Hg and/or diastolic BP of < or =60 mm Hg) was increased in the population with SSHL.

CONCLUSION

Systemic hypotension must be considered as the possible cause responsible for the development of SSHL in young healthy subjects.

A relationship between autoimmune thyroiditis and benign paroxysmal positional vertigo?

Benign paroxysmal positional vertigo (BPPV) is a labyrinthine disorder with a typical behavior: intense crises of rotational vertigo induced by postural changes of the head, with short duration and usually good responsiveness to rehabilitative maneuvers. This phenomenon is thought to be subsequent to the movement of floating particles in the labyrinthine fluids, which can provoke gravitational stimulations. In order to conduct a metabolic and autoimmune examination, 70 patients affected by BPPV were examined. In 34 cases (48.5%) autoimmune alterations were found: in 19 cases (27.1%) the level of anti-thyroid antibodies far exceeded the normal values with a significant incidence in comparison with a control group (P<0.01). No other 'risk factors' were present. It can be hypothesized that the diffusion of immune-complexes in the inner ear could change the composition of the endolymphatic fluid exerting a mechanical stimulation of the receptors and provoking the typical vertigo.

Hypotension and sensorineural hearing loss: a possible correlation

A possible role of hypotension in the genesis of sudden or slowly developing sensorineural hearing loss has been outlined. In order to confirm this hypothesis, and to exclude other vascular risk factors, a prospective study was carried out within the "Brisighella Study", a wide and homogeneous group of subjects thoroughly examined from a metabolic and cardiovascular point of view. Among them, 20 participants aged 50 years or less (18 women, 2 men) with diastolic blood pressure < or = 60 mmHg and/or systolic blood pressure < or = 105 mmHg were selected and underwent otological and audiometric examinations. Patients with previous audiological, vestibular and otological diseases were excluded. The control group was represented by 100 subjects (60 women, 40 men), aged 50 years or less, randomly chosen from within a sample of the normal population in the same region. A statistically significant incidence of sensorineural hearing loss was recorded in the study group (7/20 subjects, all affected by low-frequency hearing loss), while hearing impairment was observed in only 3/100 participants in the control group. The mean values of the main metabolic parameters were normal. An alteration of the vasomotor system associated with a hypotensive condition could be responsible as a possible factor in the origin of a cochlear damage and the consequent sensorineural hearing loss.

Small acoustic neuromas: monitoring the growth rate by MRI

In a proportion of small acoustic neuroma patients, monitoring with magnetic resonance imaging shows no volumetric increase of tumour size over the years. The object of the study was to identify some indications for the clinical choice between immediate surgery (with the related risks) and watchful waiting. We performed a retrospective study of 47 non-surgically-treated patients affected by acoustic neuroma and monitored by gadolinium-enhanced MRI between January 1990 and February 1999. Six clinical variables (tumour size, sex, age, initial symptoms, ABR pattern and duration of the symptoms) were examined by univariate analysis. Chi-square test and variance analysis were performed to evaluate the statistical significance. In 30/47 (63.8%) cases, no growth was observed during the entire period of follow-up. In the remaining 17/47 (36.2%) patients, a volumetric increase was detected, most often within the first year of observation. The clinical factors examined did not significantly correlate with growth. Despite the relatively short period of observation, we believe that immediate surgery does not need to be considered mandatory for small acoustic neuromas, even in young patients. However the irregular behaviour of the tumour underlines the importance of monitoring with MRI at least once a year.

[Metastasis in the inner auditory canal]

Metastasis in the inner auditory canal (IAC), or more precisely in the pontocerebellar angle (PCA) is extremely rare. Indeed acoustic neurinoma (AN), meningioma and other types of benign neoformations, in decreasing order, account for nearly all expansive pathologies in this anatomical region. The present paper reports a clinical case of a patient with the sudden onset of an hearing loss in the right ear. This hearing loss was promptly followed by paralysis of the homolateral facial nerve. The function of both cranial nerves worsened progressively and rapidly. Cerebral radiology, performed with MRI and the administration of gadolinium, showed a AN-compatible neoformation fundamentally affecting the IAC. However, histological tests performed after surgery indicated an adenocarcinoma. Post-operative instrumental tests identified the primary neoplasm in the lower lobe of the right lung. The purpose of this work was to highlight, in view of the literature on the topic, the main clinical aspects to consider when a malignant expansion is suspected in the PCA. Naturally there is greater basis for such suspicion when a primary malignant neoplasm has previously been diagnosed. Generally AN progresses quite gradually, in line with an extremely slow growth rate. Therefore it is normally seen in a progressive worsening of hearing, tinnitus and equilibrium disorders. Appearance of a facial nerve palsy is strictly limited to relatively large neoplasms and is encountered at a later stage. This is why a rapid progression of hearing damage accompanied, or promptly followed, by complete facial nerve paralysis must alert one to the possibility of a PCA malignancy. Imaging does not permit easy pre-operative diagnosis since the radiological signs and morphologies are often quite similar to those produced by AN. Therefore, post-operative histological examination can hold some surprises.

Can hypotension episodes cause cochlear damage in young subjects?

In the absence of a satisfactory interpretation, sudden sensorineural hearing loss is often attributed either to infective phenomena or to organic-type circulatory defects. This latter pathogenesis inevitably comes to mind in elderly patients or in the presence of signs of circulatory dysfunction. Nevertheless, the not-infrequent observation of sudden hearing loss in young persons lacking factors predictive of short-term vascular impairment makes us suppose the existence of etiopathogenetic mechanisms of a functional nature. A survey of our cases, matched with a control group, revealed the presence of lower mean blood pressure levels in the group of young patients with 'idiopathic' sudden hearing loss. This finding supports the hypothesis that a condition of haemodynamic imbalance linked to hypotension plays a role in the genesis of cochlear damage in young subjects. Such a mechanism would bear important therapeutic implications: should it be responsible for the damage in at least some cases, vasoactive drugs with a vasodilatative action could have adverse effects on the possibility of recovery.

The role of hypotension in the pathogenesis of sudden hearing loss

The generic term 'sudden hearing loss' indicates the lack of knowledge about the etiology and pathogenesis of this phenomenon. In most cases it would seem feasible to consider infections or organic circulatory defects, but there are cases, generally affecting young subjects in whom the damage is often reversible, in which a functional origin is possible. We therefore investigated the possible effect of systemic arterial pressure in a retrospective study in a group of 36 patients aged not more than 40 years, treated for sudden hearing loss, comparing the mean values of their arterial pressure with those of a control group of 25 subjects, of similar age, admitted for other disorders. The significantly lower mean values of arterial pressure in the group affected by sudden hearing loss and the easier reversibility of the damage in these patients suggests that, at least in some cases, the cochlear damage may be caused by a perfusion deficit due to the combined effect of hypotension and imperfect vasomotor regulation.