INTRODUCTION

Tinnitus is a sound sensation felt by an individual independently of external sonorous stimulation. It is usually known as shrilling, whistling, shower or fall noise, etc. It happens in a continuous or intermittent, mono or polytonal way. Its intensity can vary and discomfort is not always associated with it (1). It should be considered as either a disease symptom or as a consequence from hearing system wound (1). It can occur or not concomitance of hearing loss of different types and degrees (2-4).

Tinnitus can be classified either as subjective when it is heard only by the patient, or objective when other people can also hear it. In relation to intensity, it can be: light, when realized only by the patient in certain situations; medium, when the patient is aware of its existence but it does not disturb him or her; intense, when unpleasant sensation disturbs him/her, harming him/her in different situations or activities; disabling when its occurrence is unbearable, disturbing him/her continuously, harming patients in their daily activities.

In relation to origin, tinnitus can be periotic or sensorineural. Periotical tinnitus is originated by structures next to inner ear and conducted to cochlea. Its main causes can be muscular, tubary and vascular. Periotical tinnitus is produced in spiral or Corti organ and in neural hearing pathways, which may be peripheral, when originated in spiral or Corti organ, and central when originated in hearing pathways of the central nervous system (1). This kind of tinnitus happens more often, it is the most disturbing one and it is difficult to be treated, because its physiopathology is not well known yet (5).

Some authors say that tinnitus can happen from the presence of damaged external ciliated cells and normal internal cells (6).

Tinnitus is one of the three otoneurological manifestations together with sensorineural hearing loss and dizziness, being in many cases the main patient complaint, especially from elderly people (1, 5, 7, 8).

As tinnitus is one of the otoneurological symptoms, which affect patients physically and psychologically, its special diagnosis must be strictly done. Sometimes, the symptoms are severe (1) and present in otological diseases or not, and they can appear with secondary effect to some medicines.

The target of this current study was to verify the vestibulocochlear findings in individuals with tinnitus without dizziness complaint.

MATERIAL AND METHODS

4 males and 7 females, aging from 28 to 70, with tinnitus complaint without dizziness, were examined. They were sent to Otoneurology lab of Tuiuti University of Paraná, in Curitiba, by ENT doctors.

After authorization, through free and clear consent by a signed document and approval by the Institutional Ethics Committee, the individuals were submitted to the following protocols:

Anamnesis: a questionnaire was applied focusing on otoneurological signs and symptoms, family and personal antecedent.

ENT (ear, nose and throat) evaluation: it was made with the purpose of eliminating any alterations, which might interfere in the exam.

Hearing evaluation: conventional threshold tonal audiometry was made with audiometer Interacustics AC 40, headphones TDH 39P and with threshold in dB NA. After that, it was researched the determination of speech threshold and of speech recognition percent rate in acoustically designed booth to prevent any foreign noise which might interfere in the test.

Classifications of Davis and Silvermann (9) and SILMAN and SILVERMANN (10) were applied to describe hearing loss type and degree.

Acoustic Immitance Measurement: it was done to evaluate ossicular tympanic system by tympanometric curve and acoustic reflex research integrity. It was used the gadgets Interacoustics AZ-26 impedanciometer and headphones. JERGER (11) criteria were applied for interpretation of results.

Vestibular Evaluation: Individuals were submitted to the following tests composing the vestibular exam:

Without Record

- Positional nystagmus without record, with eyes opened, in order to verify the presence of nystagmus and/or dizziness related to body changing position, through BRANDT e DAROFF (12) movement. This movement deals about changing sitting position into head and body bending to the reported side as vertigo causing. The head is bending 45o in opposite direction, from sitting position, with nape leaned on a horizontal plan at the end of position. Then, the individuals return to sitting position and repeat all but on the opposite side.

- Spontaneous and semi-spontaneous nystagmus with eyes open, front direction look, and 30o look to right and left, and up and down.

With record

To do vectoeletronistagmography exam, it was used a thermosensitive device, Berger, VN316 model, with three record channels. After cleaning the skin of periorbitary regions using alcohol, an active electrode is attached with electrolytic paste, to the lateral angle of each eye and frontal medium line, forming an isosceles triangle, which made the identification of oblique, vertical and horizontal eye movements possible. This type of vectoeletronistagmography has enabled in obtaining more accurate measurement of the slow component (vestibular correction) of nystagmus. It was also used a Ferrante adjustable height pendular swivel chair, a Neurograff visual stimulator, EV VEC model, and a Neurograff air otothermometer, NGR 05 model, with air temperature of 42oC, 18oC e 10oC for the heat test. These tests were done according to PADOVAN AND PANSINI (13) and MANGABEIRA-ALBERNAZ et al. (14) criteria.

- Eye movement calibration related to 10º of horizontal eye movement in 10mm of amplitude in the first channel movement, and 5mm of height of second and third channels, which was fitted according to ocular deviation of 10º on vertical axis. The sheet speed was 5mm per second. In this step of the exam, the evaluated clinical aspect was regularity of the line, what could make researches comparable.

- Spontaneous nystagmus (eyes open and closed) and semi-spontaneous nystagmus (eyes open) research. Occurrence, direction and inhibiting effect of eye fixation, and the value of maximum angular speed of the slow component of the nystagmus were evaluated in this record.

- Pendular tracking research to evaluate curve occurrence and type.

- Optokinetic nystagmus research at a speed of 60º per second, clockwise and anti clockwise, in horizontal position. It was evaluated the occurrence, direction, maximum angle shape speed of slow component to shining bar of clockwise and anti clockwise movement and also calculated the nystagmus direction preponderancy relation.

- Pre and post-rotatory nystagmus research in relation to pendular rotatory, stimulating lateral, anterior and posterior semicircular ducts. In order to stimulate lateral semicircular ducts (horizontal), head was bent 30o to front direction. Next, head was bent 60o back and 45o to right, and then 60o back 45o to left, respectively to soothe anterior and posterior semicircular (vertical) ducts. It was observed the occurrence, direction and frequencies to clockwise and anti-clockwise rotation and nystagmus direction preponderancy calculation.

- Pre- and post- caloric nystagmus research. It was done with individuals placed in a way that the head and body remained bent backward at 60o, to suitable stimulation of the lateral semicircular ducts. Irrigation ear time with air at 42oC, 18oC and 10oC lasted 80s to each temperature and responses were recorded with eyes closed, and then, with eyes open in order to observe inhibiting effect of eye fixation. In this evaluation were observed the direction, total values of angle shape speed of slow component and calculation of the relation of direction and post caloric nystagmus labyrinthic preponderancy.

Statistical Analysis

Fischer test was applied with the purpose of verifying the importance of the result of caloric test and vestibular exam in relation to sex.

The level of rejection on voided hypothesis was established at 0.05% or 5%, and significant values were marked with an asterisk.

RESULTS

The results of the research of positional, spontaneous and semi-spontaneous nystagmus without record, eye movement calibration, spontaneous and semi-spontaneous nystagmus with record, pendular tracking, optokinetic nystagmus, pre and post rotatory, had no alterations.

The caloric test and vestibular exam, in relation to sex, are in Tables 1 and 2. According to Fischer test, there was no expressive difference when analyzing caloric test and vestibular exam results, in relation to sex.

The result analysis of the vestibular exam in relation to hearing loss according to side and sex can be observed on Table 3. It is important to mention that six patients (54,6%) presented normal hearing and conductive hearing loss did not occur in any of the cases.

On Table 4 we demonstrate frequencies of vestibular exam results in relation to the hearing loss degree and on Table 5 frequency of tinnitus incident place in relation to types of occurred peripheral vestibular syndromes.

DISCUSSION

It did not occur any alteration on vestibular evaluation without record made through positional, spontaneous and semi-spontaneous nystagmus, according to JÓZEFOWICZ- KORCZYNSKA and PAJOR (15) and BROOKLER (16,17) studies.

On vestibular evaluation with record, we observed normality on eye movement calibration, on spontaneous nystagmus research, semi-spontaneous, on pendular tracking and, pre and post rotatory optokinetic nystagmus research. The observed alterations occurred on caloric test. In the researched literature, SHULMAN (18) mentions suppression of vestibuloocular reflex and pendular tracking research. JÓZEFOWICZ- KORCZYNSKA and PAJOR (15) made evident abnormal records in relation to the research of pendular tracking in 38%, to optokinetic nystagmus in 20%, and of saccadic movements in 36% of the cases. BROOKLER (16,17) talked about alterations only in caloric test in accordance with our study.

On post-caloric nystagmus and vestibular test results related to sex (Tables 1 and 2) analysis, we observed alteration on peripheral vestibular system on the 11 studied cases. BROOKLER (16,17) has also found, in his studies, alterations on vestibular system. JÓZEFOWICZ-KORCZYNSKA AND PAJOR (15) and SHULMAN (18) have found larger number of alterations on central vestibular system. We have found five cases (45.5%) of hyporeflexia, two males (18.2%) and three females (27.3%). Six cases (54.6%) of labyrinthic hyperreflexia, two were males (18.2%) and four females (36.4%). This resulted five cases (45.5%) of deficient peripheral vestibular syndrome, two males (18.2%) and threes females (27.3%). Six cases (54.6%) of irritative peripheral vestibular syndrome, two were males (18.2%) and four females (36.4%). We have not found expressive differences statiscally on the analysis of caloric test and of vestibular exam result in relation to sex. Confronting researched literature, BROOKLER (16,17) mentions labyrinthic reduction in 63% of his studies. We have not found sex co-relation in the literature.

In relation to hearing loss type and vestibular exam result (Table 3), we observed sensorineural type in four of the cases (36.4%). Three of them were males (27.3%) of uni- and bilateral, with topodiagnosis of unilateral deficient and unilateral irritative peripheral vestibular syndrome, and the other one was female of unilateral occurrence with topodiagnosis of unilateral irritative peripheral vestibular syndrome. The mixed type occurred in one female case (9.1%) of unilateral occurrence with topodiagnosis of bilateral irritative peripheral vestibular syndrome. It is important to mention that six (54.6%) out of the eleven evaluated cases presented normal hearing. Co-relating these findings to literature, SANCHEZ et al. (19) have pointed that tinnitus occurrence in individuals with normal hearing can be explained by diffuse damage up to 30% of external cilliated cells in all spirals of cochlear duct, without endangering hearing threshold. JÓZEFOWICZ-KORCZYNSKA and PAJOR (15), BROOKLER (16) and RIBEIRO et al. (20) have found prevalence of uni- and bilateral sensorineural hearing loss. PINCHOFF et al. (21) have assured to be common the association of tinnitus with sensorineural hearing loss. The mixed type of hearing loss was mentioned in the literature by BROOKLER (17) and RIBEIRO et al. (20) and, the conductive uni- and bilateral type by RIBEIRO et al. (20).

Analyzing vestibular exam result and the degree of hearing loss (Table 4), we find descending bilateral moderate degree in two of the cases (18.2%). One in unilateral deficient peripheral vestibular syndrome and the other in unilateral irritative peripheral vestibular syndrome. The unilateral descending moderate degree occurred in two cases (18.2%). One was in unilateral deficient peripheral vestibular syndrome and the other in unilateral irritative peripheral vestibular syndrome. Lastly, moderate degree with incision occurred in one case (9.1%) in unilateral irritative peripheral vestibular syndrome. In the consulted literature we did not find this co-relation in order to compare with our findings.

In relation to tinnitus place of occurrence in vestibular syndromes (Table 5), we have found one case (9.1%) in bilateral deficient peripheral vestibular syndrome in the head; four cases (36.4%) in unilateral deficient peripheral vestibular syndrome, two occurred in the head and two in both ears; two cases (18.2%) in bilateral irritating peripheral vestibular syndrome, one in both ears and the other in the head, and four cases (36.4%) in unilateral irritative peripheral vestibular syndrome, three of them (27.3%) in left ears and one (9.1%) in both.

We also observed that tinnitus occurred independently of the damaged labyrinthic side. JÓZEFOWICZ-KORCZYNSKA and PAJOR (15) mention one case of prevalence of unilateral tinnitus in 74%, but they did not make any relation with vestibular exam result. BROOKLER (16,17) mentions the presence of tinnitus on the side that labyrinthic reduction occurred.

We say the importance of the vestibular exam, thus we have observed a high rate of changed exams in individual without dizziness complaint. Studies often describe functional, emotional and cognitive changes in this type population.

CONCLUSION
1) All patients presented alteration on vestibular exams in caloric test;
2) 100% of the exam alterations were in peripheral vestibular system;
3) In relation to hearing, the prevalence of normality occurred in 54.6% of the cases followed by mixed and sensorineural hearing loss type;
4) In relation to hearing loss, we observed the descending bilateral moderate type, followed by the descending and moderate with incision;
5) In relation to tinnitus place of occurrence, we observed prevalence in both ears and in the head

BIBLIOGRAPHY

1. Fukuda Y. Zumbido: diagnóstico e tratamento. RBM-ORL 1997, 4(2): 39-43.

2. Mongan E, Kelly P, Nies K, Porter WW, Paulus HF. Tinnitus as an indicator o therapeutic serumsalicylate levels. Jama 1973, 226:142-5.

3. Miller MH, Jakinetz JR. Noise exposure, hearing loss, speech discrimination and tinnitus. J Laryngol Otol. 1984, 9:74-6.

4. Dauman R, Cazals Y. Auditory frequency selectivity and tinnitus. Eur Arch Otorhinolaryngol. 1989, 246: 252-55.

5. Fukuda Y. Zumbido e suas correlações otoneurológicas. In:Ganança MM. Vertigem tem cura? 1ª ed. São Paulo; Ed. Lemos. 1998, p.171-6.

6. Hall YH, Haynes DS. Audiologic assessment and consultation of the tinnitus patient. Seminars in Hearing 2001, 22(1):37-49.

7. Henri JL, Wilson PH. Coping with tinnitus: two studies of psychological and audiological characteristics of patients with high and low tinnitus related stress. RBM-ORL 1997, 4(2): 39-43.

8. Mota PHM, Franco ES, Monteiro Pinto ES, Arieta, AM. Estudo do equilíbrio no idoso por meio da electronis¬tag¬mografia. Acta Awho [periódico online] 2002 jul-dez [citado 2005 abr 6]; 21(3). Disponível em: URL: http://www.actaawho.com.br/edicao/conteudo.asp

9. Davis H, Silverman RS. Hearing and deafness.3ª ed. New York; Ed. Holt, Rinehart & Wilson. 1970. p. 253-79.

10. Silman S, Silverman CA. Auditory diagnosis, principles and applications. 1ª ed. London; Ed. Singular Publishing Group. 1991. p. 215-32.

11. Jerger J. Clinical experience with impedance audiometry. Arch Otolaryngol. 1970, 92:311-24.

12. Brandt T, Daroff RB. Physical therapy for benign paroxysmal positioning vertigo. Arch Otolaryngol. 1980, 106:484-5.

13. Padovan I, Pansini M. New possibilities of analysis in electronystagmography. Acta Otolarygol. 1972, 73:121-5.

14. Mangabeira-Albernaz PL, Ganança M.M, Pontes PAL. Modelo operacional do aparelho vestibular. In: Mangabeira-Albernaz PL, Ganança MM. Vertigem. 2.ed. São Paulo: Ed. Moderna; 1976. p. 29-36.

15. Józefowicz-Korczynska M, Pajor A. Evaluation of oculomotor tests in patients with tinnitus. Int.Tinnitus J. 2002, 8(2): 100-3.

16. Brookler KH. Vestibular findings in a patient with a history of tinnitus before developing Méniere's disease. Ear Nose Throat J. 2003a, 82: 522.

17. Brookler KH. Electronystagmography: Vestibular findings in a patient with tinnitus. Ear Nose Throat J. 2003b, 82: 673.

18. Shulman A. Vestibular test battery correlates and tinnitus J Laryngol Otol. 1984, 9:181-3.

19. Sanchez TG, Zonato AY, Bittar RSM, Bento RF. Controvérsias sobre a fisiologia do zumbido. Arq Otorrinolaringol. 1997, 1(1): 2-8.

20. Ribeiro PJ, Iório MCM, Fukuda Y. Tipos de zumbido e sua influência na vida do paciente: Estudo em uma população ambulatorial. Acta Awho 2000, 19(3): 125-35.

21. Pinchoff RJ, Burkard RF, Salvi RJ, Coad ML, Lockwood AH. Modulation of tinnitus by voluntary jaw movements. J Laryngol Otol. 1998, 19(6): 785-9.