Recovery Nystagmus in Vestibular Neuritis with Minimal Canal Paresis. Clinical Observation and Interpretation.

Recovery nystagmus in vestibular neuritis patients is a reversal of spontaneous nystagmus direction, beating towards the affected ear, observed along the time course of central compensation. It is rarely registered due either to its rarity as a phenomenon per se, or to the fact that it is missed between follow-up appointments. The aim of the manuscript is to describe in detail a case of recovery nystagmus found in an atypical case of vestibular neuritis and discuss pathophysiology and clinical considerations regarding this rare finding. A 26-year-old man was referred to our Otorhinolaryngology practice reporting "dizziness" sensation and nausea in the last 48 h. Clinical examination revealed left beating spontaneous nystagmus (average slow phase velocity aSPV 8.1°/s) with absence of fixation. The head impulse test (H.I.T.) was negative. Cervical vestibular evoked myogenic potentials (cVEMP) and Playtone audiometry (PTA) were normal. Romberg and Unterberger tests were not severely affected. A strong directional preponderance to the left was found in caloric vestibular test with minimal canal paresis (CP 13%) on the right. The first follow-up consultation took place on the 9th day after the onset of symptoms. Right beating weak (aSPV 2.4°/s) spontaneous nystagmus was observed with absence of fixation, whereas a strong right directional preponderance (DP) was found in caloric vestibular test. A brain MRI scan was ordered to exclude central causes of vertigo, which was normal. The patient was seen again completely free of symptoms 45 days later. He reported feeling dizzy during dynamic movements of the head and trunk for another 15 days after his second consultation. The unexpected observation of nystagmus direction reversal seven days after the first consultation is a typical sign of recovery nystagmus. Recovery nystagmus (RN) is centrally mediated and when found, it should always be carefully assessed in combination with the particularities of vestibular neuritis.

Contribution of Vestibular-Evoked Myogenic Potential (VEMP) testing in the assessment and the differential diagnosis of otosclerosis.

BACKGROUND: The aim of this prospective clinical study was to evaluate the clinical importance of Vestibular-Evoked Myogenic Potentials (VEMPs) in the assessment and differential diagnosis of otosclerosis and otologic diseases characterized by "pseudo-conductive" components. We also investigated the clinical appearance of balance disorders in patients with otosclerosis by correlating VEMP results with the findings of caloric testing and pure tone audiometry(PTA). MATERIAL AND METHODS: Air-conducted(AC) 4-PTA, bone-conducted(BC) 4-PTA, air-bone Gap(ABG), AC, BC tone burst evoked VEMP, and calorics were measured preoperatively in 126 otosclerotic ears. RESULTS: The response rate of the AC-VEMPs and BC-VEMPs was 29.36% and 44.03%, respectively. Statistical differences were found between the means of ABG, AC 4-PTA, and BC 4-PTA in the otosclerotic ears in relation to AC-VEMP elicitability. About one-third of patients presented with disequilibrium. A statistically significant interaction was found between calorics and dizziness in relation to PTA thresholds. No relationship was found between calorics and dizziness with VEMPs responses. CONCLUSIONS: AC and BC VEMPs can be elicited in ears with otosclerosis. AC-VEMP is more vulnerable to conductive hearing loss. Evaluation of AC-VEMP thresholds can be added in the diagnostic work-up of otosclerosis in case of doubt, enhancing differential diagnosis in patients with air-bone gaps. Otosclerosis is not a cause of canal paresis or vertigo.

Vestibular evoked myogenic potentials in patients with BPPV.

BACKGROUND: The probable cause of Benign Paroxysmal Positional Vertigo (BPPV) is a degeneration of the oto lithic organs (utricle and saccule). The aim of the study is to find possible alterations in Vestibular Evoked Myogenic Potentials (VEMP) recordings in BPPV patients, because the saccule is part of the VEMP pathway. MATERIAL/METHODS: 27 BPPV patients (24 unilateral and 3 bilateral) aged 20 to 70 years and 30 healthy age matched controls. BPPV was diagnosed by the upbeating geotropic nystagmus found in the supine position with the head overextended towards one side. The subjects were investigated with pure tone audiometry, bi-thermal caloric test with electronystagmographic (ENG) recording, and VEMP recording. RESULTS: P1 latency and N1 latency did not present any statistical difference between control ears and affected ears of the BPPV population. The percentage of abnormal VEMP in the BPPV population was statistically higher than in the control ears (p < 0.005). No significant relationship could be shown between the occurrence of Canal Paresis and abnormal VEMP. No relationship was found between the side (right or left ear) where BPPV appeared clinically and the side where abnormal VEMP was registered. CONCLUSIONS: BPPV is a clinical entity associated with increased occurrence of abnormal VEMP recordings, possibly due to degeneration of the saccular macula, which is part of the neural VEMP pathway.

Maturation of the auditory system: 1. Transient otoacoustic emissions as an index of inner ear maturation.

The transiently evoked otoacoustic emission amplitude of 42 preterm babies (84 ears; post-conceptional age [PCA] 30-36 weeks) was compared with the TEOAE amplitude of 39 full-term babies (78 ears; PCA 37-45 weeks) in order to trace the inner ear maturation characteristics. An ILO-92 otoacoustic emission recording system was used with linear clicks of 70 dB peak equivalent SPL. The results obtained indicated: (1) There was no statistically significant difference between preterm and full-term ears; (2) There was no significant difference between males and females; (3) There was a significant difference between left and right ear TEOAE amplitude; (4) The interaction of ear with age in relation to TEOAE amplitude was statistically significant; (5) Noise and stimulus parameters did not reveal any significant differences between right and left ears; (6) A positive correlation existed between birthweight and TEOAE amplitude; and (7) A negative correlation existed between aminoglycoside treatment and TEOAE amplitude. The results indicate subtle changes in TEOAE amplitude over time, showing a natural development of the inner ear function during the process of maturation.

Maturation of the auditory system: 2. Transient otoacoustic emission suppression as an index of the medial olivocochlear bundle maturation.

Contralateral suppression of transient otoacoustic emissions in 42 premature babies (84 ears; post-conceptional age [PCA] 30-36 weeks) was compared to that of 39 full-term babies (78 ears; PCA: 37-45 weeks). Eighteen healthy adults and ten young children (5-14 years old) were studied as controls. Risk factors for hearing loss were registered in both preterm and full-term groups. An ILO-92 otoacoustic emission recording system was used to deliver linear clicks to the ear examined and broadband noise to the contralateral ear in an alternating on and off mode. Suppression in full-term babies was statistically higher than in preterms, whereas no differences existed between children and adults and children and full-terms. Peripheral auditory lateralization was evident in adults but was observed only as a trend in newborns. Only prematurity at the time of examination and aminoglycoside treatment for more than seven days had a negative impact on suppression. The results support the conclusion that maturation of the efferent system takes place from 30 to 45 weeks PCA. The exact age at which this maturation is accomplished has not yet been clearly determined.

Inverted papilloma of the sphenoid sinus: presentation of three cases.

INTRODUCTION: Inverted papilloma deriving originally from the sphenoid sinus is extremely rare. Three such cases are presented aiming to show the particularities and diagnostic clues of this clinical entity. CASE REPORTS: All three patients were male, and presented mainly with nasal symptoms. In all three cases imaging shows the sphenoid sinus was completely occupied by the tumor. Additionally the ethmoids and nasal cavities have been invaded in contiguity to the site of the initial appearance of the tumor. In particular one of the cases was of even more interest as a malignant transformation of the inverted papilloma of the sphenoid sinus was histologically observed. Endoscopic sinus surgery was the therapeutic approach chosen for all three cases, with very good results. Follow up 30 months after the operation has not revealed any signs of recurrence of the disease. CONCLUSION: Inverted papilloma of the sphenoid sinuses--and even more malignant transformation--although quite rare, may present occasionally. The ENT surgeon should be aware of this condition. Preoperative imaging with CT scan and MRI and the experience of the surgeon will dictate the appropriate surgical approach.

Transient otoacoustic emissions in the detection of olivocochlear bundle maturation.

OBJECTIVE: The medial olivocochlear bundle, forms a neural pathway connecting the superior olivary complex to the outer hair cells of mainly the contralateral cochlea. Although the biological significance of the bundle remains ambiguous, it is clear that activation of medial olivocochlear fibers alters cochlear output and this can be experimentally evident through a series of changes on otoacoustic emissions, called otoacoustic emission suppression. The aim of this study is to observe the maturation of the medial olivocochlear bundle by measuring the suppression effects on transient otoacoustic emissions. METHODS: The study population consisted of 27 premature babies (53 ears) from the P&A Kyriakou Neonatal Intensive Care Unit (conceptional age: 31-36 weeks) and 43 fullterm babies (61 ears) (conceptional age: 37-42 weeks) from the same unit. The ILO-92 system is used to deliver both the linear clicks to the ear examined (producing the emissions) and the white noise to the contralateral ear. The mode used is based on the alternating on and off presence of the white noise in the contralateral ear. RESULTS: 12/53 (22%) ears of preterm babies presented suppression > or =1 dB. 32/61 (52.4%) ears of fullterm babies presented suppression > or =1 dB. The mean suppression for the ears of premature infants was 0.52 dB, (+/-0.1 S.E.M.). The mean suppression for the ears of fullterm infants was 0.90 dB, (+/-0.09 S.E.M.). At the second half of the time window, suppression of fullterms rises above 1 dB (a pattern similar to that of adults), whereas it remains below 1 dB for preterms. CONCLUSIONS: Suppression of otoacoustic emissions helps us to study the function of the medial olivocochlear bundle in different populations. It appears in premature babies but becomes stronger as the postconceptional age advances.

Success rate of newborn and follow-up screening of hearing using otoacoustic emissions.

OBJECTIVE: During the last 6 years, and after a long period of pilot study, a universal newborn hearing screening program based on otoacoustic emissions is implemented in Iaso Maternity Hospital. Our purpose is to present the success rate of otoacoustic emission testing on discharge from the hospital and 1 month later. METHODS: All full-term newborns who were screened during a period of 2 years and failed testing after one or more sessions of transiently evoked otoacoustic emissions, on discharge from the hospital, were included in the study. These newborns were retested approximately 1 month after discharge. RESULTS: Twenty-five thousand and thirty-two newborns were examined in total. We found 534 (2.1%) 'refer' cases. Only 223 of them (41.8%) returned to retest in follow-up after 1 month. From the rescreening, 59 (2.3 per thousand) newborns failed in the test again and were referred for diagnostic audiological evaluation. CONCLUSIONS: The rate of referrals was small, but efforts should be made to decrease it further. The final number of 'failures' found, approaches the expected rate of definitely diagnosed deafness reported from other settings. The main problem we have still to confront is the high missed to-follow-up rate.

The efficacy of transiently evoked otoacoustic emissions in the detection of middle-ear pathology.

BACKGROUND: Transiently evoked otoacoustic emissions (TEOAEs) is an objective diagnostic method of assessing the cochlear status. The aim of this study was to present the results of hearing screening in children and to evaluate TEOAEs in the diagnosis of middle-ear pathology compared with tympanometry and pure-tone audiometry. MATERIAL/METHODS: A group of school-aged children underwent otolaryngological evaluation, tympanometry, TEOAEs, and audiometry. We analyzed data from both ears with abnormal tympanograms and ears with normal tympanograms but abnormal otoscopic findings or positive otologic history. Included in our study were 497 ears. RESULTS: Two hundred ten (42%) ears had a tympanogram of type A, 102 (20.5%) of type B, and 185 (37.5%) of type C. Otoacoustic emissions were found in 200 (95%), 37 (36%), and 145 (78%) of these ears, respectively. In ears with a tympanogram of B type and present otoacoustic emissions, a pure-tone average (PTA) worse than 30 dB HL was found in 16 ears (43%), whereas in ears with a tympanogram of B type and absent otoacoustic emissions, PTA worse than 30 dB HL was found in 47 ears (72.3%). The respective numbers for ears with a tympanogram of C type were 18 (12.4%) and 19 (47.5%). CONCLUSIONS: TEOAEs may be recorded in significant percentages of ears with abnormal tympanograms and middle-ear pathology. Although the sensitivity of this method is low, it may be used in conjunction with other methods of evaluating the middle ear and may give some information about the hearing status of the ear.

The effect of different 'pass-fail' criteria on the results of a newborn hearing screening program.

'Pass' criteria in newborn hearing screening programs are important, since they affect the operating characteristics of the programs. In the present study, we intended to compare the results of two screening procedures, using different 'pass' criteria, in two samples from the same pool of screened newborns. The subjects were divided into two study groups, screened consecutively during 6 months. Testing and all procedures were exactly the same in both groups, differing only in the 'pass' criteria. In the first group a signal-to-noise ratio of at least 3 dB in the frequency bands of 1-2, 2-3 and 3-4 kHz was considered necessary for a 'pass', whereas a signal-to-noise ratio > or =6 dB was used in the second group, at the same frequency bands. During the period of the study, no other minor or major modification of the protocol was applied. The comparison of the screening predischarge results between the two groups showed no statistically significant differences in the 'pass-refer' results. Thus, it appears that the 3-dB signal-to-noise ratio is as valid as the 6-dB criterion, and it may be confidently used, especially in settings where rescreening is not available.