SU1704760A1 - Device for recording the parameters of nystagmus - Google Patents

Abstract

The invention relates to medical technology and can be used in otolangology, neuropathology and neurosurgery. The aim of the invention is to detect the activity of the receptors of the vestibular apparatus by measuring the speed of the slow nystagmus phase. The device comprises a corneo-retinal potential sensor 1, an amplifier 4 and a voltage matching unit 7 connected in series, a registration unit 2 and a trigger trigger 3. In addition, the device includes a minimum value comparator 9, synchronizer b, timer 8 and mixer 5. connected in series, the first analog switch 10, divider 13. analog combiner 17, inverting amplifier 14, second analog switch 15, repeater 19 and block 20 measurements connected in series, a maximum value selector 11, an inverter 12 and a third analog switch 18 connected in series, as well as a storage and correction capacitance. The output of amplifier 4 through mixer 5 is connected to registration unit 2, the output of matching unit 7 is connected to the minimum value comparator 9 input and the first input of the second analog switch 10, the second input of which is connected to the timer 8 output, and the maximum selector 11 input values, the output of the latter is connected to the second input of the second analog switch 15, the output of which is connected to a storage capacitor 16. The output of the inverter 12 is connected to a correction capacitor 21, the output of the third analog switch 18 connect a second input of analog adder 17. The output of flip-flop 3 and pusk.ch - a second input of the synchronizer 6. 2-yl. YO VI Oh 5 Oh Oh

Description

The invention relates to medical technology and can be used in the field of otolangology, neuropathology and neurosurgery.

The aim of the invention is to detect the activity of the receptors of the vestibular apparatus by measuring the speed of the slow nystagmus phase.

FIG. 1 shows a block diagram of the device; in fig. 2 - time diagrams of the operation of the device blocks.

A device for recording nystagmus parameters contains a sensor 1 of a corneoretinal potential, a recording unit 2, a trigger 3, an amplifier 4, a mixer 5, a synchronizer 6, a matching block 7, a timer 8, a minimum value comparator 9, a first analog switch 10, a maximum selector 11 values, inverter 12, divider 13, inverting amplifier 14, second analog switch 15, storage capacitor 16, analog adder 17, third analog switch 18, repeater 19, measurement unit 20, correction capacitor 21.

The device works as follows.

A sensor 1 of a corneoretinal potential is installed on the patient's head and a signal to be measured is taken. Amplifier 4 amplifies this signal to the magnitude necessary for normal operation of registration unit 2 (Fig. 2, O. 4).

The amplified signal through one of the inputs of the mixer 5 enters the registration unit 2 and is reflected on the chart tape as a sequence of positive or negative polarity cycles, the minimum values of which correspond to the line of zero potential on the chart tape. At the same time, the signal enters the input of the matching unit 7, where the required polarity is selected and the signal is further amplified to a value that ensures the efficiency of the circuit as a whole.

The signals of the selected (positive) polarity from the output of the matching unit 7 are fed to the input of the comparator 9 minimum values, causing the appearance of a sequence of positive pulses at its output (Fig. 2. Out. 9). The triggering of the comparator 9 minimum values occurs at that moment in time when the amplitude of nystagmus cycles is equal to the selected minimum value.

The trigger 3 trigger in its initial state has at its output the potential O. When triggered 3 is triggered, the potential 1 is formed, which arrives at one of the

inputs of synchronizer 6. As a result, the next positive pulse from the output of the comparator is 9 minimum values, which arrives at the second input of the synchronizer

b, causes the appearance of a leading edge of a positive pulse at the output of synchronizer 6 (Fig. 2, out. 6), which, in turn, starts timer 8 (wig. 3, out. 8). In this case, the output of the timer 8

0 a positive impulse is formed, the duration of which is chosen in advance. The latter, acting on the second input of the mixer 5, leads to a shift upward relative to the isoline, the signal recorded on the chart tape, while not distorting its shape (Fig. 2, O. 5).

At the same time, the output signal of timer 8 is fed to the control input of the first analog switch 10, providing

0 passing the input signal through the information input to the selector 11 maximum values and through the divider 13 to the first input of the analog adder 17. When reaching the first nystagmenic

By a cycle of the maximum (amplitude) value, a positive impulse is generated at the output of the selector 11 (Fig. 2, OUT 11). which opens the second analog switch 15 and closes the third via inverter 12

0 analog switch 18. Moreover, the closure of the latter takes place with some delay, which is provided by the correction capacitor 21 (Fig. 2, out. 12).

At the time of opening the second analog key 15, the potential on the storage capacitor 16 is zero. The same potential is at the output of the repeater 19 and, therefore, through the still open third analog switch 18 at the second input of the analog adder 17, Therefore, in the analog adder 17, the voltage value corresponding to the amplitude of the first nystagmenic cycle and zero is summed up: (Ai + 0) .

5 The output voltage of the adder 17 through the inverting amplifier 14 is fed to the information input of the second analog switch 15 and charges the storage capacitor 16. It is more intense than the storage capacitor 16 through the repeater 19, goes to the measurement unit 20 (Fig. 2, output 19) and the information input of the already closed third analog key 18.

When the output of the first analog key 10 of the second nystagmenic cycle appears, the process of summation and accumulation repeats with the only difference that the voltage on the storage capacitor 16 in the initial state is equal to AI, and after summation - (A2 + AI) and t .d The average speed of the slow nystagmus phase over a selected time interval T directly is proportional to the total amplitude of unsteady cycles.

After the end of the time delay T of the timer 8, the voltage at the output of the repeater 19 is equal to ZAi, and the voltage value of the last nystagmental cycle is summed up as it is at the time of the end of the time delay, even if the last nystagmental cycle has not reached its maximum value.

After documenting the measurement results read from the measurement unit 20, resetting the trigger 3 start, synchronizer 6 and discharge of the storage capacitor 16, the device is again ready to work in the mode of measuring the speed of the slow nystagmus phase.

Thus, the device allows detecting the activity of the receptors of the vestibular apparatus by measuring the speed of the slow nystagmus phase, moreover, quantitative information is obtained immediately after the end of the measurements, which ensures highly informative studies.

Claims (1)

Apparatus of the Invention A device for recording nystagmus parameters, comprising a root-potential potential sensor, an amplifier and a voltage matching unit connected in series, as well as a registration and start trigger device, characterized in that, in order to detect the activity of the receptors of the vestibular apparatus by measuring the speed of the slow nystagmus phase, a minimum value comparator, a synchronizer, a timer and a mixer are entered into it connected in series, first analog switch, divider, analog adder, inverting amplifier, second analog switch, repeater and measuring unit connected in series, maximum selector of values, an inverter and a third analog switch connected in series, as well as a storage and correction capacitors, and the amplifier output is connected to the recording unit through a mixer, the output of the matcher - with the input of the minimum value comparator and the first input of the first analog switch, the second input of which is connected to the output of the timer, and the output - with the input of the maximum selector values, the output of the latter is connected to the second input of the second analog switch, the output of which is connected to a storage capacitor, the output of the inverter is connected to a correction capacitor, input the third analog key is with the second input of the analog adder, and the trigger trigger output is with the second synchronizer input. J ", x.4 “I.i; A.CH . g Bt /.// I 54 / H.G2 CL