The diagnostic value of earlier and later components of Vestibular Evoked Myogenic Potentials (VEMP) in multiple sclerosis

AIM OF THE STUDY

To evaluate the ability of VEMP to disclose spatial dissemination of Multiple Sclerosis.

MATERIALS AND METHODS

Forty-six MS patients with auditory and/or vestibular symptoms were studied. Patients were divided in two groups. Group 1 included 24 patients with brainstem MRI findings, and Group 2 included 22 patients without MRI findings. VEMP and BAEP have been recorded and assessed.

RESULTS

Abnormal p13n23 wave was observed in 50%, while unilateral absence or bilateral delay of the n34p44 in 43% of the patients. The overall diagnostic value considering abnormal cases suggested by both first and second VEMP waves was increased to 71%. Statistically significant differences revealed between patients and controls for p13 latency (p=0.018). The p13n23 was abnormal in 7 patients, although MRI scanning did not reveal brainstem lesions. In 9 out of 18 MS patients suffering from unilateral hearing loss, n34p44 was present in the unaffected ears and absent in the affected side, although p13n23 was normal.

CONCLUSION

Abnormal VEMP imply the presence of lesions undetected by MRI neuroimaging, which verifies the diagnostic value of the method. Unilateral absence of n34p44 complex was related with sensorineural hearing loss, supporting the hypothesis that n34p44 is of cochlear origin.

Using vestibular evoked myogenic potentials to localise brainstem lesions. A preliminary report

BACKGROUND

Vestibular Evoked Myogenic Potentials (VEMPs) are saccular responses to acoustic stimuli. They can be recorded from the sternocleidomastoid muscle ipsilaterally to the stimulated ear. Their reflex arc includes the ipsilateral vestibular nuclei.

OBJECTIVE

To determine the usefulness of VEMPs in localising brainstem lesions.

METHODS

We used VEMPs, Blink Reflex (BR) and Brainstem Auditory Evoked Responses (BAERs) to evaluate six patients presenting with acute ischaemic or haemorrhagic brainstem lesions, or basilar dolichoectasia.

RESULTS

MRI in patient one revealed a dorsolateral medullary infarct on the right. VEMP amplitude was reduced ipsilaterally. The R2 BR component was delayed bilaterally upon stimulation of the affected side. Patients two and three had suffered a left lateral lower pontine infarct and a right lateral lower pontine haemorrhage. In patients four and five, MRA revealed dolichoectasia of the basilar artery exerting pressure on the lower lateral pons. VEMP amplitude was reduced ipsilaterally. Patient six had an ischaemic lesion in the right upper lateral pons. The R1, R2i and R2c BR components were delayed ipsilaterally. BAERs waves IV and V were absent on the right. VEMPs were normal.

CONCLUSIONS

VEMPs are affected by lesions of the lateral lower pons and upper medulla. Our results suggest that they may be a useful addition in the localisation of such lesions.

Long-term effects of chemotherapy for acute lymphoblastic leukemia on the medial olivocochlear bundle: effects of different cumulative doses of gentamicin

OBJECTIVE

The treatment of acute lymphoblastic leukemia (ALL) often combines a neurotoxic chemotherapeutic protocol such as Berlin-Frankfurt-Munster-95 (BFM-95) with gentamicin, an antibiotic known to have an early and quickly reversed impact on olivocochlear reflex in animal studies. This study investigates whether this combination has any long-term side effects on the medial olivocochlear bundle (MOCB).

METHODS

In all 47 children of the study suppression of distortion product otoacoustic emissions (DPOAEs) by contralateral application of white noise (WN) was used to assess the function of the MOCB. The population was divided into three groups depending on the time interval between the end of therapy and examination. The group examined shortly after chemotherapy included 12 children who had received low gentamicin doses (less than 13 days). The group evaluated 2 years after therapy involved another 12 children who had required medium gentamicin doses (more than 13, less than 23 days). The group examined 3 years after therapy included a subgroup of 12 children to whom low gentamicin doses were infused and another 11 children with high gentamicin doses (more than 23 days).

RESULTS

Three years after therapy the olivocochlear reflex was efficiently produced in both subgroups of low and high gentamicin doses. Two years after therapy, contralateral WN induced increase of DPOAEs at 4 of the 12 examined frequencies. Shortly after therapy, WN increased, instead of suppressing, DPOAEs at five frequencies.

CONCLUSION

This abnormal result of contralateral noise application perceived as impaired cochlear efferent innervation may indicate that ALL-BFM-95 exerts a toxic effect on the MOCB, which is slowly reversed within the first 3 years after chemotherapy and does not seem to be affected in the long term by different cumulative doses of gentamicin.

Surgical correction of pinna malformations

BACKGROUND

Auricle reconstruction is a surgical procedure described in the medical literature as early as 600 BC. The aim of the present paper is to review these attempts and their results.

METHODS

Literature search and medical history books were used as scientific sources.

RESULTS

More than 40 different cartilagenous, osseous or other alloplastic frame materials (autogenous tibial bone, iliac bone, mastoid bone, maternal auricular cartilage, autogenous nasoseptal cartilage, allogenous meniscus, autogenous meniscus and many more) have been used since 1891. From approximately 40 reconstruction procedures that had been proposed, only eight were still in use in the 1980s. The reason for abandoning the majority of these surgical techniques was the unacceptable aesthetic result. However, at the end of the 20th Century two new techniques were introduced. These techniques were designed by Satoru Nagata and Burt Brent. Both techniques provide cosmetic and functional results that are acceptable both to the patient and to the surgeon.

CONCLUSIONS

Although the outcome of surgical auricle reconstruction was in general disappointing through the centuries, at the end of the 20th Century new surgical methods were established and at the present time auricle reconstruction can be attempted with acceptable results.

Lemierre's syndrome associated with consumption coagulopathy and acute renal failure: a case report

Background:

Acute tonsillitis or pharyngitis may lead to suppurative thrombophlebitis of the internal jugular vein. This complication, also known as Lemierre's syndrome, remains, even nowadays, life threatening, due to dissemination of septic thromboemboli to various organs. Respiratory deficiency and renal impairment are often reported in patients suffering from Lemierre's syndrome.

Case report:

The unusual clinical manifestation of this case involves severe acute renal and respiratory deficiency in addition to microangiopathic consumption coagulopathy in a young patient treated with macrolides five days after the onset of acute tonsillitis.

Conclusion:

The usual causative pathogen, namelyFusobacterium necrophorum, shows a varying sensitivity to macrolides. As a result, the syndrome may present itself in a variety of clinical forms even in patients under treatment with macrolides. A high index of suspicion is therefore crucial for in time prevention of potentially life threatening complications.

Non-Hodgkin's lymphoma of nasal cavity and paranasal sinuses. A clinicopathological and immunohistochemical study

Aim of this study was to investigate the clinical characteristics, management and prognosis of non-Hodgkin lymphomas of the nasal cavity and paranasal sinuses. Overall 12 patients with non-Hodgkin malignant lymphoma, at our Institute, were studied over an eight-year period from 1997 to 2005. Patients' data collected were age, sex, presenting signs and symptoms, histology, treatment, complications, and outcome. Also available were computerised tomography findings, and paraffin-embedded tissue bocks. Mean age was 62 years (range: 42-81), with a male dominance (male to female ratio: 7:5). Most patients had not presented any specific symptoms, such as nasal obstruction, headaches, epistaxis and facial swelling. Using immunocytochemistry on paraffin-embedded tissue sections, the predominance of large B-cell subtype was detected. Treatment administered: only radiotherapy (stage IEA) or in combination with chemotherapy (IIE-IVE). Of these patients, 5 died from the disease, 4 survived without disease, 2 survived with the disease, and one died of non-related causes. Non-Hodgkin's lymphomas are relatively rare. Early diagnosis, based mainly on tissue biopsy and computerised tomography, is essential in the management of non-Hodgkin lymphoma.

Neurotoxicity of vincristine on the medial olivocochlear bundle

OBJECTIVE

Vincristine is a well known neurotoxic chemotherapeutic agent. Dose dependent and cumulative peripheral neuropathy is the main dose limiting side effect of chemotherapy with vincristine. The mechanisms responsible for the neurotoxic effects of vincristine have not yet been fully understood. This prospective study was directed at determining whether vincristine treatment interferes with the function of the medial olivocochlear bundle.

DESIGN

Fifteen children suffering from leukemia were subjected to tympanogram, stapedial muscle reflex, pure tone audiometry and transient evoked otoacoustic emissions (TEOAEs) in the absence and presence of contralateral white noise on day 1 and on day 22 of treatment with vincristine. The function of the medial olivocochlear bundle was assessed by the phenomenon of suppression of otoacoustic emissions by contralateral application of white noise.

RESULTS

The study revealed a statistically significant decrease of contralateral suppression amplitudes in all cases after three sessions of chemotherapy with vincristine. On the contrary no alterations were observed in pure tone audiometry thresholds. A non-significant decrease of the mean TEOAEs' amplitudes was also noted. When analyzed by frequency, however, this decrease reached the level of statistical significance at two frequencies.

CONCLUSION

Vincristine treatment seems to exert a neurotoxic effect on the efferent olivocochlear system, which takes place early in the course of chemotherapy. This is a new aspect to be added to the possible mechanisms underlying the toxicity of vincristine in the auditory periphery. Whether changes in efferent function might contribute to understanding the mechanisms of neurotoxicity caused by vincristine, or find any clinical application as a predictor or early detector of neurological side effects of vincristine still remains to be seen.

Hydatid cyst in the duct of the submandibular gland

The case of a hydatid cyst located in the duct of Wharton of a 56-year-old farmer is reported not only because of the unusual location of the disease, but also because the clinical manifestations and surgical findings of the hydatid cyst strongly resembled those of a salivary calculus in the duct of Wharton. The patient presented with a non-painful swelling of the right submandibular region. The mass, which appeared 5 years before seeking medical advice, augmented progressively during the first year after its onset and remained stable during the next 4 years. The subsequent surgical excision of the mass was uneventful and a round mass, which was palpated intraoperatively in the duct of Wharton was assumed to be a sialolith. The diagnosis for a hydatid cyst of the duct of Wharton was made by histological examination. Although salivary calculus is the most common finding in cases of obliteration of the duct of Wharton, histological examination of the surgically excised submandibular gland may reveal benign tumours. In extremely rare cases where hydatid cysts are located in the cervicofacial area, a detailed further diagnostic procedure is required in order to diagnose possible involvement of other organs.

Topical antibiotic ear drops: are they safe?

A discharging ear is a very common condition for the general practitioner and the ENT surgeon. Oral and intravenous antibiotics have potential complications, are costly, and exhibit increasing resistance. This study explores the advantages and disadvantages of all common otic preparations and compares effectiveness, safety, cost and complication rates. In chronic otitis media (chronic discharging ears), topical antibiotics seem to be the treatment of choice by comparison with oral or intravenous antibiotics. Cultures and antibiograms do not correspond directly to clinical efficacy, as laboratory determination of resistance does not take into account the high concentration of antibiotics in local preparations. It is safer to use quinolone drops as a first-line treatment, but it is still possible to use short courses of other drops if quinolones are either unavailable or contraindicated (e.g. allergy), or when bacteria are resistant to them. However, in such a situation, a round window membrane involved in an established inflammatory process and therefore less permeable to the passage of topical preparations is the preferred setting, as ototoxicity is a potential complication, especially in the case of gentamicin, in which case patients should be warned accordingly.

Should We Use Ossicular Remnants in Ossicular Reconstruction following Cholesteatoma Removal?

The remnants of the acoustic ossicles have been used in ossicular reconstruction during mastoid surgery for many decades. The present study assessed the status of the acoustic ossicles in 114 patients (57 with cholesteatoma and 57 without) during surgery for chronic otitis media using the operating microscope. In 52 cases, the ossicles (malleus and/or incus) were assessed using both the surgical and scanning electron microscope in order to reveal any erosions and compare the findings. From the 57 operated ears with cholesteatoma, 45 (79%) had ossicular erosion whereas 12 (21%) did not. In the group of 57 operated ears with chronic otitis media without cholesteatoma, 33 (58%) had ossicular erosion whereas 24 (42%) did not. This difference was statistically significant (p = 0.02). With regard to the 52 operated cases who were studied with both microscopes, in the cholesteatoma patients the surgical microscope was not able to reveal any ossicular erosions in 39% of the cases, whereas the scanning electron microscope revealed moderate or severe erosions in the same ears. This suggests that the operating microscope is not reliable enough to determine if ossicular remnants can be used in ossicular reconstruction following cholesteatoma surgery. There is a considerable risk that epithelia or other cholesteatoma particles remain in the areas of erosions that cannot be seen with the operating microscope. The use of such ossicular remnants may lead to cholesteatoma recurrence and failures in mastoid surgery. Therefore, autoclaving or alternative prosthesis may be considered in such cases.

The effect of treatment with vincristine on transient evoked and distortion product otoacoustic emissions

OBJECTIVE

Vincristine chemotherapy is mainly associated with neurotoxic effects. The ototoxicity of vincristine has been related to high dosage, while low and moderate doses do not seem to induce significant hearing impairment when measured by pure tone or speech audiometry. Otoacoustic emissions have been reported to be more sensitive in early detection of ototoxicity than conventional pure tone audiometry. The present study was directed at determining whether vincristine treatment interferes with outer hair cell function in the absence of measurable changes in pure tone audiometry.

METHODS

We studied prospectively a cohort of ten children suffering from leukemia. All children were subjected to tympanogram, stapedial muscle reflex, pure tone audiometry, transient evoked (TEOAEs) and distortion product (DPOAEs) otoacoustic emissions on day 1 and on day 22 of treatment with vincristine. TEOAEs were analyzed in terms of emission level and reproducibility as a function of frequency. DPOAEs were obtained as DP-grams and were analyzed in terms of amplitude.

RESULTS

The analyzed parameters of TEOAEs and DPOAEs revealed a declining tendency, although changes did not reach statistical significance. Pure tone audiometry and stapedial reflex thresholds were not altered.

CONCLUSION

For the population of this study, vincristine did not seem to cause significant alterations of otoacoustic emissions' recordings and consequently significant outer hair cell damage.

Prognosis of patients with benign paroxysmal positional vertigo treated with repositioning manoeuvres

Objective: To evaluate the prognostic factors in benign paroxysmal positional vertigo (BPPV) treated with canalith repositioning procedures (CRPs).

Material and methods: Retrospective study of consecutive BPPV cases diagnosed over three years. All patients underwent a complete otolaryngologic, audiologic and neurotologic evaluation. The appropriate CRP was performed, depending on the type of BPPV. Prognostic factors studied included age, sex, aetiology, duration of disease, abnormal electronystagmographic findings, canal involvement, improper performance of manoeuvres, response on first or repeat treatment, and presence of recurrences.

Results: One hundred and fifty-five patients were studied, 66 men and 89 women, with mean ages of 58.7 and 60.4 years, respectively. Age and the involvement of two canals or bilateral disease had an effect on initial treatment outcome and were correlated to increased recurrences but not to repeat treatment outcome. Secondary BPPV, abnormal electronystagmographic findings and improper performance of manoeuvres had a significant effect both on initial and repeat treatment, but not on recurrences. Sex and duration of symptoms had no effect.

Conclusion: Canalith repositioning procedures provide fast and long-lasting treatment of BPPV in most patients. However, in a small subgroup of patients, failures may be noticed that may be attributed to various prognostic factors.

Newborn Hearing Screening: Effectiveness, Importance of High-Risk Factors, and Characteristics of Infants in the Neonatal Intensive Care Unit and Well-Baby Nursery

BACKGROUND

In contrast to the recommendations of the Joint Committee on Infant Hearing, neonatal hearing screening programs are still not universally available, and many countries implement elective screening in high-risk newborns.

OBJECTIVE

To assess the failure rates of neonates in hearing screening and the relative importance of risk factors for hearing impairment, both in neonatal intensive care units and in well-baby nursery neonates. The impact on cost-effectiveness is also evaluated.

SUBJECTS

In the current study, 25,288 newborns were assessed; 23,574 were full-term newborns in the well-baby nursery and 1,714 neonates were in neonatal intensive care units.

METHODS

All neonates had a general examination (including assessment for congenital anomalies and related history) and were assessed using transient evoked otoacoustic emissions. All newborns were older than 36 weeks at examination and thus had reliable transient evoked otoacoustic emissions.

RESULTS

From the 23,574 full-term neonates in the well-baby nursery, 23,123 (98.1%) passed the test and 451 failed (1.9%). Fifty-three of the 23,574 neonates (0.2%) had a risk factor for hearing impairment; 44 (83%) passed the test and 9 failed (17%). Family history of congenital hearing loss and congenital anomalies were the most frequent risk factors for hearing loss. From the 1,714 neonates in neonatal intensive care units, 1,590 (93%) passed the test and 124 failed (7%). Two hundred thirty-two of the 1,714 neonates (14%) had a risk factor for hearing impairment; 205 (88%) passed the test and 27 failed (12%). In neonatal intensive care unit neonates, toxic levels of ototoxic drugs, mechanical ventilation for more than 24 hours, prematurity, and low birth weight were the most frequent risk factors for hearing loss. Congenital anomalies/syndromes were the most important risk factors for failing screening in both the neonatal intensive care unit and the well-baby nursery, as they showed the highest risk of failing hearing screening. The second most important factor in neonatal intensive care unit newborns was low birth weight, and the third was prematurity in relation to the possibility of failing hearing screening.

CONCLUSION

The present study found 575 neonates failing hearing screening of 25,288 tested newborns (2.3%). The fact that 78% of newborns who failed hearing screening were in the well-baby nurseries further supports the necessity of universal hearing screening instead of selective screening in neonatal intensive care units, even with the obvious impact on cost-effectiveness. Even if limited funding lead to selective screening in neonatal intensive care units, this should not be applied to high-risk newborns but to all neonatal intensive care unit neonates. Continuous assessment of risk factors and the related possibility of failing hearing screening are of paramount importance in designing hearing screening programs and refining the respective criteria.

Twice-daily dosing of loracarbef 15 mg/kg versus 30 mg/kg in the treatment of children with acute sinusitis

Loracarbef is an oral synthetic beta-lactam antibiotic of the carbacephem class. The aim of this study was to compare the efficacy and safety of loracarbef 15 mg/kg versus 30 mg/kg in children with acute sinusitis. A randomized, parallel-group, clinical study was conducted. Fifty-eight children aged 5-12 years with acute sinusitis were divided into two groups, which received either loracarbef 15 mg/kg/day or 30 mg/kg/day orally, divided in two doses for 10 days. Clinical examination, anterior rhinoscopy and sinus radiographs were performed at the beginning of treatment. Clinical evaluation was repeated in a second session, 0-2 days after the final dose, and in a third session, 30 days after the beginning of the treatment. Sinus X-rays were repeated selectively in the second session and in all patients in the third session. Nineteen of 29 (65.5%) patients in the 15 mg/kg/day group and 26 of 29 (89.6%) in the 30 mg/kg/day group were characterized as completely or clinically cured at the end of the study. In conclusion, a statistically significant difference between the two treatment groups was shown with better results in the 30 mg/kg group. Despite the slight difference in adverse events between the two groups (with fewer adverse events in the 15 mg/kg group), we recommend that if loracarbef is chosen as initial therapy in acute sinusitis, a regimen of 30 mg/kg/day in two doses is followed.

Improvement of otitis media with effusion after treatment of asthma with leukotriene antagonists in children with co-existing disease

Otitis media with effusion (OME) is a common pediatric disease and there is great controversy concerning its management. Mechanical, medical and surgical treatments have not proven adequate in resolving the disease and serve mainly to manage complications. Leukotriene inhibitors are new drugs that have been approved recently for the treatment of asthma in children. The aim of this study was to evaluate the impact of leukotriene inhibitor therapy for asthma on the clinical course of OME in children with co-existing disease. Fifty children with bilateral OME and asthma, divided equally into two groups, were studied. The children in the first group were treated with budesonide and terbutaline inhalers together with the leukotriene inhibitor montelukast, whereas the children in the second group were treated with the inhalers alone. Duration of treatment was 30 days. Pneumatic otoscopy, tympanometry and pure-tone audiometry were performed at the beginning and at the end of treatment. Fifteen (60%) of the children receiving inhalers and montelukast and nine (36%) of those receiving only inhalers were found free of OME after 30 days of therapy. Thus, it may be concluded that a statistically significant beneficial effect on the clinical course of OME resulted from the addition of montelukast to the treatment of children with co-existing asthma and OME. Given that no medication has been shown to be effective in OME therapy, further investigation of the possible effects of leukotriene inhibitors is warranted.

Periodic alternating nystagmus associated with Arnold-Chiari malformation

The Arnold-Chiari malformation type I is a rare congenital condition characterized by herniation of the cerebellar tonsils into the upper cervical spinal tract. Various otoneurological manifestations occur in patients with the disease, which has usually been associated with a downbeat type of nystagmus. In this paper a case with this condition is reported presenting with periodic alternating nystagmus (PAN), which is a rare type of nystagmus observed in diseases of the central nervous system of different pathologies. The patient had a complete otoneurological examination and vestibular function testing. Diagnosis was established by using magnetic resonance imaging (MRI).

Submasseteric abscess

The masseteric space is an important tissue compartment of the neck, but disease in it is difficult to diagnose and treat. In this paper a case of a young adult male with an abscess of the submasseteric space is presented. Diagnosis was established by computed tomography (CT) of the neck, but the severity of the lesion was not accurately estimated. Surgical intervention was performed and a large quantity of pus was drained. A detailed medical history and clinical examination of the patient as well as CT are important tools in the accurate diagnosis and efficient treatment of the disease.

Vestibular suppression in peripheral and central vestibular disorders

Caloric tests have been carried out both in the presence of optic fixation and in total darkness upon normal subjects, patients with peripheral vestibular disorders and patients with central vestibular lesions. Nystagmic responses were recorded electronystagmographically and measurements made of latency and duration of response, maximum slow component velocity and beat frequency. The relative enhancement of the response in darkness is expressed as a fixation index: maximum slow component velocity in darkness maximum slow component velocity with fixation. Compared to the normal group the peripheral group were found to have abnormally high fixation indices, the central group abnormally low. A hypothesis has been developed of the nervous mechanisms underlying the suppressive effects of optic fixation in both peripheral and central lesions which accords well with the available clinical, anatomical and physiological data. The clinical implications of the findings are discussed both in respect of their localizing value and relevance to current innovations in the design of caloric tests.

Electronystagmographic criteria in neuro-otological diagnosis. 1. Peripheral lesions

Direct current electronystagmographic recordings of spontaneous nystagmus, in the light, in darkness, and with eye closure were carried out on 34 patients with peripheral lesions of the vestibular system with a view to determining their specificity. In 60% of patients the responses were characterised by an enhancement of the nystagmus both with eye closure and in darkness. The remainder exhibited no nystagmus under any recording condition.

Electronystagmographic criteria in neuro-otological diagnosis. 2. Central nervous system lesions

Direct current electronystagmographic recordings of spontaneous nystagmus in light, in darkness, and with eye closure have been carried out on (a) 33 patients with acoustic neurinomata pressing on the brain stem, and (b) 10 patients with lesions involving the brain stem at a high level. Patterns of response characteristics of each group have been identified in 21 out of 28 cases of group a, the spontaneous nystagmus present in light was abolished by eye closure and inhibited in darkness, nystagmus being absent in the remaining five; in group b the greater proportion (70-80%) of patients presented with spontaneous nystagmus in light which was abolished by both eye closure and darkness.