Doctorate

 The aim of the doctoral thesis

The aim of the doctoral thesis was to define the usefulness of the author’s own dynamic test in the evaluation of the efficiency of the equilibrium system. The research of the efficiency of the equilibrium system by means of dynamic tests seems the most physiological, easy to perform and very practical at the same time. The method of this kind of research has a large diagnostic value because movement is connected with the conditions of the daily life and reflects the adaptation of the system to the environment and human work. This method eliminates the activity of numerous incidental factors which can occur after using a caloric, rotary or galvanic stimulus or other types of stimulation. Therefore, in the examination of candidates for occupations, which requires good efficiency of the equilibrium system, dynamic tests should be the first indicatory test allowing assessment of the efficiency of this system. By means of the Unterberger dynamic test the symmetry or the asymmetry of vestibulo-cerebellospinal reflexes can be defined, however it cannot be inferred whether in a given case there is a peripheral or central injury of the vestibular organ. The diversification of peripheral and central injuries is very difficult and uncertain even with the use of electronystagmographic examination. The objective of the thesis was to assess the efficiency of the equilibrium system by means of the author’s own dynamic test, first of all, in cases of peripheral injuries of the vestibular organ whose state of efficiency determines the physiological cooperation of the whole equilibrium system.

The performed tests

   a) static-dynamic tests, the Romberg test, the Mann test, the past-pointing test, the deviating test, the diadochokinesis test, the finger-to-nose test

   b) dynamic tests: the Unterberger test and the author’s own dynamic test.

   c) audiological examination.

   d) radiological examination.

   e) eyeballs kinetics examination in the pendulum test.

   f) recording of rotatory nystagmus in the kinetic test with pendulum stimulation.

   g) the modified rotation test according to Arslan.

   h) the caloric test according to Fitzgerald-Hallpike.

   i) research into optokinetic nystagmus.

Recording of spontaneous nystagmus, positional nystagmus, the movement of eyeballs in the pendulum test and nystagmus induced in the investigated tests, was performed on thermosensitive paper by means of two-canal  electronystagmograph manufactured by Tönnies (fig. 3).

Fig. 3

All the above mentioned subjective and objective research, and, first of all, different ways of stimulation of vestibular organs were performed in order to possibly precisely define the functional efficiency of both labyrinths, both in the control group of healthy persons and ill persons with peripheral or mixed injuries of the vestibular organ. Hence, the assessment of the condition of the labyrinths was not based exclusively on one kind of stimulation but numerous ways were introduced: caloric stimulations, kinetic stimulations, simple static-dynamic tests, in order to obtain the most reliable results which in confrontation with additional research and consultations of other specialists could provide the greatest probability of correct diagnosis. It is only after working out the groups of subjects of this thesis in this way that they were put to verification with the use of the author’s own dynamic test, the pendular marking time test, in order to prove what kind of practical value this test has for approximate assessment of the efficiency of the equilibrium system and to which degree it can be useful in defining the peripheral injuries of the vestibular organ.

 MATERIAL

   a) the control group of healthy persons - 30 persons.

   b) a group of ill persons with peripheral injuries of the vestibular organ - 60 persons.

   c) the group of ill persons with other injuries of the equilibrium system - 20 persons. 

FINDINGS AND DISCUSSION

Persons in the control group were selected from persons already working in different professions in which good efficiency of the equilibrium system is required. No subject complained about vertigo and disequilibrium of their bodies. Interviews concerning ear diseases, head injuries and other illnesses which exert an essential influence on disturbances in the equilibrium system in all the subjects was negative. No subject in this group showed any weakness of hearing. Ophthalmological and neurological examinations in these persons did not reveal any deviations. In static-dynamic tests, i.e. in the Romberg test, the Mann test, the past-pointing test, the deviating test, the finger-to-nose test, the diadochokinesis test, the Unterberger test: they were correct in all persons. Correct reactions in these tests were, among other things, the basis of the preliminary qualification of the subject to the control group. The Mann test was checked with one lower limb moved forward and then the other lower limb moved forward.

 All the tests were performed efficiently. In the Fitzgerald-Hallpike's caloric test, longer reactions in tests with cold water were found. No essential time differences of the latency between the right and the left ear were not detected, however,  slightly higher average values of the latency were observed in tests with hot water. Tests with cold water also revealed higher values of the maximum amplitude, the average value of the maximum angular speed of the free phase of nystagmus and a longer reaction time of nystagmus. Analysing the average values of the number of the nystagmus saccades (n), the maximum amplitude (aM), the maximum angular speed of the free phase (vM), the duration of nystagmus, obtained in reactions of the post-rotary kinetic test according to Arslan, no significant difference between the right and left ear was found. Symmetrical reactions were obtained also in the pendulum stimulation test. The author's test, none of the subjects showed any decided rotation around their long axis of the body, during the test performed with one and the other lower limb moved forward. In seven subjects one observed a rotation which was not bigger than 15-45°, usually symmetrical from both limbs. All the subjects performed this test efficiently wihout any difficulties with maintaining the bodily equilibrium in the course of the test. Nobody from the subjects complained about vertigo or other discomfort which would make it difficult to perform this test entirely  fig. 4

.

Fig.4 The basic reaction model in the dynamic test according to Nakiela in the control group of healthy persons.

In the group with peripheral injuries of the vestibular organ (60 persons) in 31 persons one found destruction of the vestibular organ on the left side and in 29 subjects on the right side. In the classical Romberg test only in seven cases one observed slight staggering in a patient, which can be regarded as a plus-minus test. It was assumed that the positive Mass test should refer to cases in which one found evident staggering of the subject or his/her falling down. It was found that 46 subjects had evident difficulty in maintaining equilibrium with a lower limb moved forward, on the side of the damage. Normally, staggering and falling down of subjects occurred towards the injury. Among the subjects, nobody's finger-to-nose test and diadochokinesis test were positive. In 51 cases, the Unterberger test proved a rotation of the body towards the injury by an angle above 90°. Five persons showed a rotation of the body greater than 15-45°. In four cases one found a rotation of the body above 90° towards the healthy labyrinth. The positive result of the deviation test was detected in five cases, the deviating part was mainly the limb on the side of the healthy labyrinth towards the damaged labyrinth. A similar result was obtained in the past-pointing test, a positive result was noted in seven cases. The size of passing was about 10 cm. In this test one found mainly passing of the upper limb on the side of the healthy labyrinth towards the injury.  Spontaneous nystagmus with eyes closed was registered in 22 persons, positional nystagmus was detected in 33 cases. In seven persons in whom one found the canal paralysis. Spontaneous and positional nystagmus were not detected in the caloric test. The caloric test according to Fitzgerald-Hallpike was performed in 32 subjects. In the remaining ill persons the caloric test was not performed because of the existing perforation in the tympanic membrane. In 29 cases one obtained reduction of excitability, consistent with the side of the damaged labyrinth. In three subjects one obtained symmetrical reactions. In eleven cases one found the symmetrical and real directional predominance of nystagmus, including crossed and not crossed one. In the diagnostics of peripheral injuries of the vestibular organ the caloric test proved to be the most authoritative of the three performed tests. The rotation test according to Arslan and the pendular stimulation test was performed in 60 subjects.  Kinetic tests were repeated in most cases several times, however, the caloric test was performed in most cases only once. It must be underlined that during the kinetic tests for the first time, symmetrical answers from both labyrinths were often found, only in the repeated tests asymmetric answers were obtained. In the rotation test according to Arslan, for the first time symmetrical responses were obtained in 24 persons, in 7 subjects unresponsiveness was found. Similar results were received for the first time in the pendular stimulation test. In 16 cases symmetrical responses were found and in 10 persons the nystagmus reaction into both sides was not obtained. Finally, the destruction of the vestibular organ was confirmed in 42 cases in the rotation test according to Arslan, in 32 subjects in the pendular stimulation test and in 29 persons in the caloric test. The average values of the number of saccades (n), the maximum amplitudes (aM), the maximum speed of the angular free phase (vM), the duration of the reaction (t), for the group with peripheral injuries in the rotation test according to Arslan compared with the control group are clearly smaller.  These differences are statistically significant. In the canal paralysis and the symmetrical nystagmus post-rotary reaction in the test according to Arslan, these values are by half smaller. The results of this research proves that the nystagmus reactions have become steady, but on the lower activity level on both sides. In 58 persons from this group, in the author’s own test one observed a significant rotation of the body by 90° towards the damaged side during the performance of the test with a lower limb moved forward, opposite to the damage. While performing the test with a lower limb moved forward on the side of the damage, no rotation was observed in these cases, or this rotation was not bigger than 15-45° (fig. 5)

No rotation from the right lower limb moved forward	Rotation to the right from the left lower limb moved forward

Fig.5 - the destruction of the right labyrinth

The rotation of the body occurred very slowly in these persons. Only in two subjects one observed a rotation of the body by the angle above 90° towards the healthy labyrinth, during the performance of the test with the lower limb moved forward on the side of the destruction and lack of rotation while performing the test with the lower limb moved forward on the side of the unimpaired labyrinth. Both cases refer to persons with the chronic purulent inflammation of the middle ear. In 34 subjects who performed this test with the lower limb moved forward on the side of the damaged labyrinth, had difficulties in performing this test (tremor of the lower limb put forward, the feeling of uncertainty or falling down on the side of the damage). The rotation in the author’s own test in 50 cases was compatible with the sense of rotation in the Unterberger test.

 In the group with other injuries 20 persons were examined (they were mainly ill people after serious skull injuries). Taking into consideration the detailed interview, established clinical diagnoses, the ophthalmological and neurological research, the ORL research, audiological research, the entire otoneurologic research, it should be considered that the observed changes refer mainly to the central nervous system. In all persons the pendular stimulation test was performed, in 15 hundred persons the rotation test according to Arslan, in 10 persons the caloric test according to Fitzgerald-Hallpike. The Romberg's pathological test was found in fourteen ill subjects, the Mann test in sixteen subjects. The positive finger-to-nose test was found in one case, the diadochokinesis test in two cases. 8 subjects showed the positive deviation test and in 9 cases the pathological past-pointing test. In 15 persons one observed a rotation of the body by 90° in the Unterberger test, in the remaining five cases no bigger rotation than 15-45° was obtained. Spontaneous and positional nystagmus (most often with variable directions) were recorded in 15 cases. In 8 subjects examined with the caloric test the directional predominance was detected, in two subjects symmetrical reactions were obtained. Asymmetric reactions in the rotation test were found in thirteen cases, in the pendular stimulation test in seventeen persons. In the recording of the induced nystagmus one registered an irregularity of the angular speed of the free phase, pauses in the recording, the floating of eyeballs, a large variability of amplitude. The pathological recording in the pendulum test was obtained in nine cases, in the optokinetic stimulation in fourteen cases. Generally in eighteen subjects the directional predominance was obtained in the nystagmus reaction, however, in two persons symmetrical reactions were obtained; one case concerned the destruction of the left cerebellar hemisphere, the other concerned a person with past head injury with loss of consciousness. In two persons secondary nystagmus was obtained. One case concerned persons with poisoning with methanol and carbon disulphide. Secondary nystagmus was obtained only after calorization with hot water. In the same person one found a pathological finger-to-nose test on the right side, weakness of muscular power in the right upper limb, a rotation to the left in the Unterberger test. One also found a pathological recording in the pendulum test and optokinetic stimulation. The other case concerned persons with SM.  Secondary nystagmus occurred in the rotation test according to Arslan, however, it was not found in the caloric test. In the author’s own test in nineteen cases one observed a rotation over 90° from both limbs on one side. In all cases one obtained the conformity of the rotation in the author’s own test with rotations in the Unterberger test. In a subject with the destruction of the left cerebellar hemisphere (the condition after removing a tumor) no rotation was observed while performing the test with the lower limb moved forward on the side of the damage. While performing the test with the lower limb moved forward, opposite to the damage, a rotation of over 90° was observed towards the healthy side.  In the same person one found the correct Romberg test, the Mann test, the negative diadochokinesis test and the finger-to-nose test. In the Unterberger test one found the rotation of the body into the healthy side. Neither spontaneous nor positional nystagmus were found. In kinetic tests and in the caloric test one found correct, symmetrical reactions. The observations show that vestibulo-cerebellospinal reflexes in this group were more intensified compared with the group with peripheral injuries of the vestibular organ. The assessment of the efficiency of the equilibrium system is a difficult issue because of lack of uniform assessment factors as well as methods difficult to objectivize and a quickly changing image of the disease in the course of the destruction of even one links of this system. More and more often a laryngologist working in the ambulatory conditions must assess the efficiency of the equilibrium system and determine the usefulness of candidates for certain professions. Hence the need to use tests which are the simplest and the least complicated, which are practical but simultaneously good for correct assessment of the equilibrium system. If a pathology should be found, one should recognize whether the changes concern the peripheral section of the vestibular or central organ or if they are mixed. Such recognition can sometimes be made after a variety of other tests which are not always to be performed in ambulatory conditions. Research into the control group proves that there is no ideal correlation in the size of nystagmus reactions in individual tests. In persons with long nystagmus reactions and a large amplitude in the caloric test one found small nystagmus reactions in kinetic tests. Contrary situations were also observed. Gaps of maximum values and minimum values in individual tests were sometimes large. It is sometimes difficult to determine the norm for individual types of research and applied tests. It seems that in the diagnostics of the equilibrium system one should apply the biggest possible number of different tests so as to correctly assess the actual state of this system. It also turns out that the caloric test must not be treated as the basic test with reference to other tests. Analysing the average time of duration of caloric nystagmus in a group of healthy people, longer reactions in tests with cold water were found, which is in accordance with the results by Hallpike (39), Kubiczkowa (59) and Mozolewski and partners. (77).  I will explain these problems in detail in the habilitation lecture when discussing the bicaloric  test based on principles of operation of the vestibulocerebellar system. Despite the fact that the Fitzgerald-Hallpike bi-thermal caloric test has been applied since 1942, I also presented its theoretical foundations for the first time in the habilitation lecture in 1990. Comparing the results of the average values of the maximum angular speed of the free phase in the caloric test, it was found that they were close to the results provided by Braska and partners (14). The authors, when investigating a group of twenty healthy persons with the caloric test obtained the average value of the maximum angular speed of the free phase of 23,9°/s, with the range of results from 8,7-56,5°/sec. In the author’s own research the average value of the maximum angular speed of the free phase is 22,9°/sec, with the range of results from 3,5-45,3°/sec. The average time of duration of the post-rotary reaction in the rotation test according to Arslan in the author's research for the control group is 34,7 sec, the average number of saccades in the entire reaction is 64,1. Bień (8), while investigating the group of 60 healthy persons with the Barany test, whose parameters are very much similar to the rotation test according to Arslan, received similar results; the average of duration of the reaction was 32,6 sec, the average number of saccades in the entire reaction was 58,8. Similarly, he did not find any difference in excitability comparing the right ear with the left ear. The results received in the test with pendular stimulation are similar to the results presented by Greiner and partners (36), despite the fact that the stimulation was made in a reverse order. In the physiological conditions the directional predominance of nystagmus (46, 87) is observed quite frequently, because almost in 15-17% cases. Bodo (13), examining 20 healthy men with the use of the pendular stimulation, obtained four kinds of responses, including lack of nystagmus reaction despite using high angular accelerations from 20-50°/sec2. In peripheral injuries of the vestibular organ one found a very small number of cases of positive deviation and past-pointing tests. This fact can suggest that spontaneous vestibulo-cerebellospinal reflexes in these tests are quickly subject to habituation and are more frequently positive in the first twenty-four hours after the destruction of the labyrinth, when one observes, still with the eyes open, an intensive directional and optokinetic nystagmus. In the later period the above mentioned tests have a small diagnostic value. In order to cause a deviation of the upper limb on the side of the healthy labyrinth to the side of the damaged labyrinth one should perform the Ruttin symmetrical caloric test with hot water. I described these issues in detail in the habilitation lecture. A similar reaction from upper limbs in healthy people can be caused by applying the Ruttin asymmetric test with hot water or only unilateral stimulation of the labyrinth with a warm stimulant. I explained these issues in detail also in the habilitation lecture. Vestibulo-cerebellospinal reflexes were more distinct in persons in whom no traits of compensation of nystagmus reactions in kinetic tests were found. They were more lively in fresh injuries, which is compatible with Włodyka's observations (97). This author (96), investigating vestibulo-cerebellospinal reflexes in ill persons with symptoms of the destruction or paralysis of the peripheral vestibular system in the test of arm deviation, frequently observed that the arm on the side of the destruction remains still, while the opposite one clearly translocates towards the damaged side, which is in accordance with the results of reflexes vestibulo-cerebellospinal of obtained in the author’s own test. The mechanism of formation of vestibulo-cerebellospinal reflexes were also explained in detail in my habilitation lecture, presenting theoretical bases of these reflexes for the first time. In the group with peripheral injuries of the vestibular organ one found one main reaction model in the author's pendular marking time test. The observed issue was rotation towards the side of the damaged labyrinth when performing the test with the lower limb moved forward on the side of the healthy labyrinth and lack of rotation with the lower limb moved forward on the side of the damage. In two cases one noted a rotation towards the unimpaired labyrinth performing the test with the lower limb moved forward on the side of the damaged labyrinth and lack of rotation when performing the test with the lower limb moved forward on the side of the unimpaired labyrinth. It occurs in the event of reversing of the directional predominance of nystagmus towards the damaged labyrinth and the directional predominance of vestibulo-cerebellospinal reflexes towards the healthy labyrinth. Caloric tests frequently reveal symmetrical directional predominance towards the damaged labyrinth.

Similarly, in kinetic tests one obtains the predominance of nystagmus reactions towards the weaker labyrinth. These processes are connected strictly with habituation, which I also explained for the first time in the habilitation colloquium and in the habilitation lecture in 1990, when discussing the phenomenon of habituation based on the operational rules of the vestibulocerebellar system. Therefore, in peripheral injuries of the vestibular organ in the author's test, one reaction model is obtained, regardless of the fact if it concerns fresh injuries of the vestibule or cases with produced habituation (the inversion of nystagmus and vestibulo-cerebellospinal reflexes). When assessing vestibulo-cerebellospinal reflexes, the dynamic tests have a definite advantage over the static tests. The development of my further research was largely influenced by observation of vestibulo-cerebellospinal reflexes in the Unterberger test and in the author’s own dynamic test in an ill person after tumor surgery of the left cerebellar hemisphere. In the Unterberger test one found a rotation towards the healthy side. In the author's dynamic test one obtained a rotation towards the healthy side when performing the test with the lower limb moved forwards on the side of the healthy hemisphere. When performing the test with the lower limb moved forward on the side of the damaged cerebellar hemisphere, no rotation was observed. The destruction in this case was confirmed only in these two dynamic tests, while in kinetic tests and the caloric test symmetrical nystagmus reactions were obtained.  This observation is in accordance with the reflexes obtained in the arm deviation test caused on a swivel seat - Taniewski (76). While rotation a healthy person to the left it is visible that after stopping the swivel chair her upper limbs deviate left, however, in an ill person with the destruction of the cerebellum on the right side, the left arm deviates left, and the right arm stays still/marking time. Therefore, the unilateral destruction of the labyrinth and the cerebellar hemisphere has different influence on the limbs on the other side of the damage. In the destruction of the labyrinth we deal with adduction to the side of the injury, in the destruction of the cerebellar hemisphere we deal with abduction of the limb to the healthy side. These observations had a great influence on constructing a hypothetical experimental research model for healthy people, and consequently it contributed to understanding the operational rules the vestibulocerebellar system. By means of this model I was in a position to cause in healthy people the same vestibulo-cerebellospinal reflexes from upper limbs as I obtained from lower limbs in my own dynamic test in people suffering from the destruction of the labyrinth or the cerebellar hemisphere. These parallel studies allowed me to make sure that the observations of reflexes in my own dynamic test in ill persons with peripheral injuries of the vestibular organ and in ill persons with the destruction of the cerebellar hemisphere were correct. I will explain these problems in the habilitation lecture. Therefore I proved that in peripheral injuries we deal with a deviation of one limb and not both limbs towards the side of the damaged labyrinth as it is universally described in otoneurology textbooks. The author's dynamic test seems to be a perfect test in the diagnostics of peripheral injuries of the equilibrium system. In the carried out research my dynamic test proved to be a very sensitive test, by means of which one can define not only the asymmetry of vestibulo-cerebellospinal reflexes but also the efficiency of the entire equilibrium system. Performing the pendular marking time with eyes closed provides a certain degree of difficulty for the subject. Persons with the partly efficient or inefficient equilibrium system clearly have difficulty completing this test, often making pauses and breaks. We say that this is a test which has a certain practical value. It can be performed almost in every ambulatory conditions. Performing this test entirely does not take too much time, which is of special importance in investigating a large number of persons in the daily ambulatory work of a neurologist or a laryngologist. The own test can turn out to be sometimes the only test to indicate the existing pathology within the equilibrium system. This will take place in those cases in which we obtain the minimum and a hardly readable nystagmus reaction. In rotation tests in the group with peripheral injuries of the vestibular organ symmetrical reactions frequently occurred, which was explained by the compensation phenomenon. However, repeating the rotation test in short intervals results in receiving asymmetric responses with a predominance of reactions towards the ampulopetal deviation of the cupula, i.e. towards the unimpaired labyrinth. By applying a stronger rotary stimulus, i.e. not a physiological one, we cause dehabituation in the vestibulo-cerebellar system. In ill persons with canal paralysis symmetrical reactions were obtained in the rotation test, but the value of individual parameters of post-rotary nystagmus as, e.g.: the duration of the nystagmus reaction, the number of saccades of eyeballs, was smaller by half than in healthy persons' reactions. This is understandable because the energy flowing from one labyrinth was damaged. The only organ responsible for the reaction after rotations left and right is the healthy labyrinth. This observation proves that in the physiological conditions in healthy persons, both labyrinths are equally responsible for the rotatory and post-rotary reaction to the right and left. I could not include these observations in my doctoral thesis because it would challenge the binding LeDoux theory which claims that the organ responsible for the development of rotatory nystagmus is only one labyrinth, i.e. the one towards which the rotation takes place. I could not reveal these discoveries because my thesis supervisor Prof. Bożydar Latkowski, M.D., Ph.D. was an author of many papers on rotation tests and LeDoux's theory is considered as binding everywhere. I knew my place and I knew what I am allowed to do. I could develop my research only in the scientific underground without informing anybody about the progress. Now I am convinced that if I had tried to emphasize these discoveries in my doctoral thesis, I would not have obtained the Doctor of Medicine degree. On the basis of the carried out research the following conclusions have been drawn:

CONCLUSIONS

1. The author's modification of the Unterberger test seems to be a very simple and practical test which can be used in the daily ambulatory and clinical work.

2.  This test allows us to assess in general the state of the efficiency of the equilibrium system as well as permitting us to exploratively define the character of the damage.

3. In the group of healthy persons, in the modified Unterberger test one does not observe a rotation around the long axis of the body or this rotation is not bigger than 15-45°.

4. In the group with the peripheral destruction of the vestibular organ one observes a rotation towards the damaged side, while performing the test with the lower limb moved forward on the side opposite to the side of the damage, and lack of rotation while performing the test with the lower limb moved forward on the side of the damage.

5. In the group with other injuries, mainly of the central type, one observes a rotation to one of the sides, irrespective of the fact which lower limb is used to take a step forward.

6. One did not find any close relationship in the size of the nystagmus reaction in the used kinetic and caloric tests, which  seems to indicate the necessity of performing several vestibular tests so as to comparison the responses.

7. In cases of any reduction of excitability and canal paralysis, in the group with peripheral injuries of the vestibular organ, one found a phenomenon of compensation of responses in rotation tests performed one by one.

The thesis contains 80 pages, 108 items of literature reference.

The thesis supervisor - Professor Bożydar Latkowski, M.D., Ph.D., The Head of the Laryngological Clinic of The Military Medical Academy in Lodz.

Reviewers:

  - Professor Janusza Kubiczkowa, M.D., Ph.D., The Head of the Laryngological Clinic of the Military Institute of Aeromedicine in Warsaw.

  - Professor Jan Laciak, M.D., Ph.D., The Head of the Laryngological Clinic of the Medical Academy in Lodz.

The doctoral defense was held at the Military Medical Academy in Lodz in 1978. The thesis supervisor did not give his permission to entitle my doctoral thesis as I proposed: "Research into the usefulness of the author's dynamic test in defining the efficiency of the sense of equilibrium". The title was changed by the thesis supervisor and finally it was: "Research into the usefulness of the modified Unterberger test in defining the efficiency of the sense of equilibrium". In 1983, during the National Laryngological Congress in Lodz I presented my film (directed by Tadeusz Halatek) entitled: "Research into the equilibrium system", presenting my own dynamic test and its value in otoneurological diagnostics. I was given a stormy standing ovation by participants of the congress from the full conference hall in the Chief Technical Organization (NOT).