RU2761931C1 - Method for neurophysiological study of the motor portion of the pudendal nerve in pudendoneuropathy - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to neurology and functional diagnostics, and can be used for neurophysiological study of the motor portion of the pudendal nerve in pudendoneuropathies. A neurophysiological study of the response to magnetic stimulation, an analysis of the latency of the M-response is carried out. At the same time, a magnetic stimulator is used as stimulation equipment. An active disposable surface silver chloride electrode is applied alternately to the bulbocavernosus muscles on the right and left. In men, the electrode is applied to the most protruding areas of the bulbocavernosus muscles, determined by palpation, in women at a distance of 0.5 cm from the entrance to the vagina, along the outer edge of the labia majora. The reference electrode is attached to the inner surface of the thigh of the same name, the center of the magnetic inductor is located at the level of the II-IV sacral vertebrae in the center. The current in the inductor coil is directed counterclockwise for the right side and clockwise for the left side, the magnetic field power is set to 100%. Stimulation is carried out until an M-response is received. In the presence of an M-response and the maximum value of the latency of the M-response up to 13.85 ms inclusive, it is believed that the conduction along the pudendal nerves is within normal limits. At values of more than 15.28 ms, it is considered that there are conductivity problems. At values from 13.85 ms to 15.28 ms inclusive, it is considered that there is the boundary condition.

EFFECT: method provides an increase in the accuracy of the diagnosis of damage to the pudendal nerve in both men and women by determining the M-response and the value of M-response latency.

4 cl, 5 ex

Description

The proposed invention relates to medicine, namely to neurology and functional diagnostics, and can be used to determine damage to the pudendal nerve in patients with pudendoneuropathies.

The pudendal nerve is mixed and innervates the levator anus, the coccygeal muscle, the sphincter of the anus, the transverse perineal muscle, the bulbous-cavernous muscle, the urethra, the corpora cavernosa, and the skin of the perineum.

The most common forms of pudendoneuropathies are tunnel and post-traumatic. The latter include overstretching of the nerve during childbirth and sports, trauma to the nerve in case of pelvic fractures, bruises, the intersection of its branches during surgical interventions, etc. Tunnel pudendoneuropathies are caused by compression of the pudendal nerve in anatomically formed canals ("tunnels"), as well as in narrow anatomical spaces. The pudendal (pudendal) nerve can be compressed under the tense piriformis muscle, between it and the sacrospinous ligament, between the latter and the sacro-tuberous ligament, and in the Alcock canal, formed by the split fascia of the internal obturator muscle. At the same time, interligamentary compression occurs much more often than intracanal (68% and 13%, respectively). At the same time, despite the fact that the problem of pudendoneuropathies sufficiently reduces the quality of life of patients, there are still no clear recommendations for the prevention and treatment of this disease.

When the pudendal nerve is compressed in places of anatomical traps in patients, neuropathic pain syndrome (pudendal neuralgia) predominates in the clinical picture. Neuralgia of the pudendal nerve due to compression can be determined clinically, however, a vivid clinical picture develops after a long time from the onset of the initial symptoms, when conservative treatment is already ineffective. When the nerve is traumatized or the compression worsens, sensitive prolapse appears in the area of pudendal innervation, as well as symptoms and signs characteristic of rectal and urinary tract dysfunction in the form of sphincter disorders and sexual dysfunction (erectile dysfunction, anorgasmia).

There are instrumental methods for diagnosing lesions of the pudendal nerve, which, however, give only an indirect idea of its involvement in the pathological process:

Ultrasound of the pudendal nerve allows visualization of the nerve is possible only with high-resolution equipment with many additional functions that improve the image quality, while there are no clear compression criteria.

Ultrasound of the internal genital artery, which follows as part of the neurovascular bundle in the Alcock canal, with a decrease in the linear blood flow velocity (LFV), suggests its compression, and, consequently, compression of the nerve;

MRI of the pelvic organs with the capture of the lumbosacral plexus allows visualizing perineural fibrosis or scar in the area of the nerve course, thickening of the pudendal nerve, thickening and fibrosis of the fascia of the internal obturator muscle, mass effect of any adjacent formations, bone injuries and their consequences, fatty infiltration, edema and atrophy of the internal obturator muscle, fibrosis and thickening of the sacro-tuberous and sacrospinous ligaments. Moreover, in the case of a pathological process of small prescription, no changes may be detected.

The use of the above methods for the most part allows you to obtain additional information about the possible causes of the patient's condition only at the later stages of the pathological process, while they require expensive equipment and the appropriate qualifications of the specialist conducting the study.

Another way to diagnose the state of the pudendal nerve is neurophysiological research, but the information content of the available methods is a subject of discussion: some experts consider it high, others low.

The main disadvantage of the existing methods of neurophysiological diagnostics is that most of them are invasive due to the use of needle discharge electrodes, cause great discomfort to patients (electrode of St. Mark's Hospital) and with their help it is possible to assess the functional state of only sufficiently large myelinated nerve fibers.

To date, the following neurophysiological techniques are traditionally used to assess the state of the pudendal nerve:

1) somatosensory evoked potentials (SSEP);

2) electromyography of the muscles of the perineum (EMG);

3) electroneuromyography of the bulb-cavernous reflex (BCC).

BKR electromyography is performed as follows (https://www.androlog03.ru/bkr/, accessed 06.02.2021):

The patient is in a horizontal position, with the lower limbs bent at the knee joints and spread apart. The head of the penis is treated with electrode paste (fixing and electrically conductive contact medium) and 2 annular irritating electrodes are tightly installed on it. The skin of the perineum is treated with an antiseptic alcohol solution. With a needle withdrawal electrode, the skin of the perineum is punctured, retreating 0.5 cm to the right or left from the middle suture, and, passing through the subcutaneous tissue, the end of the needle is inserted into the bulbocavernosus muscle. The lead electrode is connected to an electromyograph, and the irritating electrode is connected to a stimulator. Electrocutaneous irritation of the penis is produced by impulses with a frequency of 1 Hz, duration 0.2 ms, current from 1 to 100 mA. By increasing the current strength, the threshold of psychosensory perception and the threshold of muscle excitation are determined. The latency period is defined as the interval between stimulation and the response recorded electromagnetic pulse. Its value of 30-40 ms is defined as the norm. Then, by increasing the electrical stimulation by 1.2-1.5 times in comparison with the reflex threshold, they achieve a stable and constant EMG discharge in the bulbocavernous muscle and process and record 10 consecutive discharges. Then the electrodes are removed and the skin of the perineum is re-treated with an antiseptic.

The disadvantages of this method include: soreness, invasiveness. If the study is performed in women, then there is a technical difficulty in its conduct and the risk of perforation of the vaginal wall. The negative point is the fact that the absence of responses to stimulation occurs even in the absence of pathology.

The objective of the proposed invention is the development of an atraumatic, non-invasive, painless and inexpensive method for studying conduction along the genital nerves, applicable to both men and women, allowing to obtain suitable M-responses for analysis.

The technical result of the method for studying the pudendoneuropathies is to improve the accuracy of diagnosing damage to the pudendal nerve, including before the appearance of neuroimaging and ultrasound signs of compression of the nerve trunk in both men and women.

The technical result is achieved by the fact that in the method of neurophysiological study of the motor portion of the pudendal nerve in pudendoneuropathies, including neurophysiological study of the response to magnetic stimulation, analysis of the latency of the M-response, a magnetic stimulator is used as a stimulation equipment, an active disposable superficial a silver chloride electrode, while in men the electrode is applied to the most protruding areas of the bulbocavernous muscles, determined by palpation, in women - at a distance of 0.5 cm from the entrance to the vagina, along the outer edge of the labia majora, the reference electrode is attached to the inner surface of the thigh of the same name, the center the magnetic inductor is placed at the level of the II-IV sacral vertebrae in the center, the current in the inductor coil is directed counterclockwise for the right side and clockwise for the left side, the magnetic field power is set to 100%, stimulation is performed until a correct M-response is received, in the presence of an M-response and a maximum value of the latency of the M-response up to 13.85 ms inclusive, it is considered that the conduction along the pudendal nerves is within the normal range, at values of more than 15.28 ms, it is considered that the conduction is impaired, and for values from 13.85 ms to 15.28 ms inclusive, it is considered that the state is borderline.

Preferably, for segmental magnetic stimulation, a Neuro-MS / D magnetic stimulator is used, combined with a Neuro MVP-4 electroneuromyograph, a round inductor 15 cm in diameter.

Preferably, surface film silver chloride electrodes with a size of 2.2 × 3.4 cm with an adhesive solid medical gel and a contact format pad for attachment to a crocodile connector are used.

Preferably, in the borderline state, the study is repeated after 3 months.

The method is carried out as follows.

The study is carried out in a warm room equipped with a screen, behind which the patient undresses in the absence of unauthorized persons (only the doctor and the patient) and irritating factors.

The patient sits on a couch, lying on his back, legs are slightly divorced, bent at the knee and hip joints, feet are on the couch. Before the examination, the doctor puts on gloves, treats them with an alcohol solution of chlorhexidine, and treats the patient's external genital organs with an aqueous solution of 0.02% chlorhexidine.

In men, alternately to the right and left of the midline of the perineum, an active disposable surface electrode is applied to the protruding areas of the bulbocavernous muscles, determined by palpation. In women, the active electrode is applied alternately to the right and left at 0.5 cm from the entrance to the vagina, along the outer edge of the labia majora. The reference electrode is attached to the inner surface of the thigh of the same name, fasteners-connectors for temporary connection of the "crocodile" type corresponding to the active and reference withdrawal electrodes are attached to the disposable surface electrodes.

A Neuro-MS / D magnetic stimulator combined with a Neuro MVP-4 electroneuromyograph (Neurosoft Company, RF) is used as stimulation equipment. The maximum power of the magnetic field is 2.6 T. For segmental magnetic stimulation, a round inductor (coil) with a diameter of 15 cm is used.

After moistening with isotonic sodium chloride solution, a grounding strip electrode is applied to any leg, to the region of the lower third of the lower leg.

The center of the inductor is located in the center at the level of II-IV sacral vertebrae (projection zone 2, 3, 4 sacral roots). The current in the inductor coil is directed counterclockwise for the right side and clockwise for the left. Stimulation is performed until the correct M-response is obtained.

The response time is 1-2 ms. The research time is 10-15 minutes. Type of information received: graphical and numerical. Analyze the latency of the received M-responses, if any. In the absence of an M-response (block of conduction), it is concluded that there is no conduction along the pudendal nerve.

If the maximum value of the latency of the M-response is up to 13.85 ms, it is considered that the conduction along the pudendal nerves is within the normal range, more than 15.28 ms, that the conduction is impaired, and at values from 13.85 ms to 15.28 ms inclusive, it is considered that borderline condition. If the condition is classified as borderline, the study is repeated after 3 months.

The method is atraumatic, non-invasive, painless, suitable for men and women and allows diagnosing damage to the pudendal nerves, including before the appearance of neuroimaging and ultrasound signs of compression or traumatic damage to the nerve trunk.

Examples of application of the method.

Example 1. Patient S., 35 years old. Was inpatient treatment in the urology department. Diagnosis: chronic pelvic pain similar to scrotal pain syndrome. Concomitant diseases: Chronic gastritis without atrophy. Chronic sinusitis without exacerbation.

Complaints of shooting pains in the scrotum, frequent urination (up to 12 times a day), erectile dysfunction.

The epidemiological history is calm. Heredity is not burdened. Profession - communication technician. The nature of labor is physical.

Medical history. Considers himself ill for about 2 years, when passing and short-term pain in the scrotum appeared. He associated exacerbations with hypothermia. Regularly engages in weight lifting with squats and lunges. Six months ago, against the background of stress, there was a deterioration in the condition, the pain in the scrotum intensified, the urge to urinate became more frequent.

Physical examination data. The condition is satisfactory. Physiological skin and mucous membranes. In the lungs, vesicular breathing, no wheezing, respiratory rate 16 per minute, clear heart sounds, rhythmic, blood pressure 130/70 mm Hg. Art., heart rate 88 beats per minute. The abdomen is soft, painless, there are no peritoneal signs. Stool, urine output are normal.

The external genital organs are formed correctly, according to the male type. Per rectum - the prostate is elastic, the contours are clear, the median groove is contoured, the palpation is painless.

In the neurological status: skin hyperesthesia in the area of innervation of the pudendal nerve on the left, anal and bulbocavernous reflexes are reduced.

According to the DN4 questionnaire, 6 points were scored (with a norm of 1-3 points), which characterizes the neuropathic component of pain.

In laboratory tests of blood, urine, smears from the urethra and urine culture for bacuria, no pathological changes were revealed.

A study was carried out according to the proposed method (the stimulation zone is segmental, the stimulation point is in the center at the level of II-IV sacral vertebrae.

From the right bulbocavernous muscle, the latency of the M-response is 12.81 ms, from the left bulbocavernous muscle - 15.29 ms. The maximum latency of the M-response is 15.29 ms, which is more than 15.28 ms; therefore, it was concluded that the conduction along the left pudendal nerve is disturbed, i.e. damage to the myelin sheath due to external compression.

According to the Doppler study of the internal genital artery (transperineal access): blood flow of the main type on both sides, a slight tortuosity of the course of the arteries on both sides, the linear blood flow velocity is reduced, more on the left; violation of blood flow in the walls of the urethra, blood flow with increased spectral characteristics IR-0.84.

MRI of the small pelvis: no pathology.

Aimed MRI of Alcock's canal: thickening and fibrosis of the fascia of the internal obturator muscles on both sides (probably on the right, the pudendal nerve in a state of subcompensation).

Thus, using the proposed method, conduction disturbances along the left pudendal nerve were revealed, which were confirmed by neuroimaging. The defeat of the pudendal nerve arose as a result of its compression in the Alcock's canal, which coincides with the MRI data. Other causes of neuropathy of the pudendal nerve were excluded by history and during the examination.

Example 2. Patient U., 31 years old. Was inpatient treatment in the urology department. Diagnosis: chronic pelvic pain of the type of vaginal and urethral pain syndrome. Concomitant diseases: Varicose veins of the lower extremities. Vertebral lumbodynia with muscular-tonic manifestations, moderate persistent pain syndrome. Chronic cystitis without exacerbation. Anxiety-depressive disorder.

Complaints of a burning sensation in the urethra, aggravated at the end of the act of urination, shooting pains in the vagina, aggravated by intercourse.

The epidemiological history is calm. Heredity is not burdened. Profession - operator, nature of work - sedentary, mental.

Medical history. Considers himself sick for about 1.5 years, when she began to notice the gradual appearance of the above complaints. About 5 years ago she suffered severe stress. For pain in the genital area, she was examined and treated by a urologist and gynecologist at the place of residence.

Physical examination data. The condition is satisfactory. In the lungs, vesicular breathing, no wheezing, BH 16 per minute, clear heart sounds, rhythmic, BP 110/60 mm Hg. Art., heart rate 88 beats per minute. The abdomen is soft, painless, there are no peritoneal signs. Stool, urine output are normal.

The external genitals are formed correctly, according to the female type. Per vaginum - painful palpation, mainly in the area of the sacrospinous ligaments, more on the left, soreness in the neck of the bladder.

In the neurological status: decreased sensitivity in the area of innervation of the pudendal nerve on the left, anal and bulbocavernous reflexes are absent.

According to the DN4 questionnaire, 5 points were scored, which characterizes the neuropathic component of pain.

In laboratory tests without deviations from the norm.

A study was carried out according to the proposed method (the stimulation zone is segmental, the stimulation point is in the center at the level of II-IV sacral vertebrae).

From the right bulbocavernous muscle, the latency of the M-response is 13.11 ms, from the left bulbocavernous muscle - 15.41 ms. The maximum latency of the M-response is 15.41 ms, which is more than 15.28 ms; therefore, it was concluded that the conduction along the left pudendal nerve is disturbed, i.e. damage to the myelin sheath due to external compression.

Instrumental survey data.

Ultrasound of the internal genital artery (transperineal access): the main type of blood flow on both sides, the linear blood flow velocity is not reduced.

MRI of the small pelvis: no pathology.

Sighting MRI of Alcock's canal: pudendal nerves and adjacent structures were unremarkable.

MRI of the lumbosacral spine: MRI picture of degenerative-dystrophic changes, protrusion of L4-S1 discs.

Due to the absence of neuroimaging and ultrasound signs of compression of the nerve trunk, the patient was not prescribed treatment. She reapplied with the same complaints after 4.5 months. At the reception, the patient reported that the pain symptoms worsened, there was frequent urination (up to 13 times a day). Repeated studies were carried out:

A study was carried out according to the proposed method (the stimulation zone is segmental, the stimulation point is in the center at the level of II-IV sacral vertebrae).

From the right bulbocavernous muscle, the latency of the M-response is 13.15 ms, from the left bulbocavernous muscle - 15.47 ms. The maximum latency of the M-response is 15.47 ms, which is more than 15.28 ms and more than the previous value of this indicator is 15.41 ms, which indicates an aggravated compression of the left pudendal nerve.

Ultrasound of the internal genital artery (transperineal access): blood flow of the main type on both sides, the linear blood flow velocity is slightly reduced on the left.

Aiming MRI of Alcock's canal: adjacent structures without features, initial signs of perineural fibrosis on the left.

The patient was prescribed treatment in accordance with the standards for the treatment of compression-ischemic neuropathies, with control of the condition after 2 months.

Research data after 2 months from the start of the study:

Magnetic stimulation according to the proposed method (the stimulation zone is segmental, the stimulation point is in the center at the level of II-IV sacral vertebrae).

From the right bulbocavernous muscle, the latency of the M-response is 13.13 ms, from the left bulbocavernous muscle - 13.77 ms. The maximum latency of the M-response is 13.77 ms, which is less than 15.28 ms and less than 13.85 ms.

The patient reported that she began to feel better, the burning sensation in the urethra decreased, the shooting pains in the vagina became less, the number of urges to urinate decreased.

This clinical example illustrates the high value of the proposed method in the early diagnosis of lesions of the pudendal nerve by assessing its conductance in conditions when neither ultrasound nor neuroimaging research methods allow revealing the interest of the pudendal nerve in the pathological process. This increases the efficiency of diagnostics.

Example 3. Patient K., 42 years old. Was being treated in a urological hospital. Diagnosis: chronic pelvic pain of the type of vaginal and urethral pain syndrome. Concomitant diseases: Arterial hypertension 2 tbsp., Risk 2.

The epidemiological history is calm. Heredity is not burdened. Complaints of burning sensation in the urethra, not dependent on the act of urination, frequent urination in small portions (up to 16 times a day), painful intercourse, sensation of a foreign body in the vagina, tearfulness, anxiety, poor sleep.

Medical history. Considers himself a patient since he was 39 years old. For a long time she was treated by a urologist and gynecologist at the place of residence, but she did not notice any particular effect. Pains persist and induce refusal to have sexual intercourse. Repeatedly passed urine cultures for flora - the results are negative. History of two independent childbirth.

Physical examination data. The condition is satisfactory. In the lungs, vesicular breathing, no wheezing, respiratory rate 16 per minute, clear heart sounds, rhythmic, blood pressure 150/80 mm Hg. Art., heart rate 76 beats per minute. The abdomen is soft, painless, there are no peritoneal signs. Stool, urine output are normal.

The external genitals are formed correctly, according to the female type. Per vaginum - when trying to study, there is a sharp pain, the patient interferes with the study. The urethra in a typical place, soft, sharply painful on palpation. Bimanual examination is not possible due to the patient's restless behavior.

In the neurological status: the cranial nerves are without pathology, the coordination tests are satisfactory, there are no paresis, tendon reflexes are symmetrical, there are no pathological signs, the sensitivity is not disturbed, the background of the mood is reduced, emotionally labile.

In laboratory analyzes, no deviations.

A study was carried out according to the proposed method (the stimulation zone is segmental, the stimulation point is in the center at the level of II-IV sacral vertebrae).

From the right bulbocavernous muscle, the latency of the M-response is 13.80 ms, from the left bulbocavernous muscle - 13.84 ms. The maximum latency of the M-response is 13.84 ms, which is less than 13.85; therefore, it was concluded that the conduction along the pudendal nerves is normal.

Instrumental survey data.

Uroflowmetry: urine volume - 236 ml, Qmax - 34 ml / s, Qav. - 18 ml / s.

Cystoscopy: the urethra is freely passable. Bladder capacity 140 ml. The mucous membrane is clean, pink; mouths on rollers.

Ultrasound of the internal genital artery (transperineal access): the main type of blood flow from both sides, the linear blood flow velocity is not reduced.

MRI of the small pelvis: signs of a cyst of the right ovary.

Sighting MRI of Alcock's canal: pudendal nerves and adjacent structures were unremarkable.

From this example, it follows that the latencies of the M-responses during abduction from the bulbocavernous muscles are within the normal range, which excludes the involvement of the genital nerves in the pathological process.

The patient was recommended to visit a psychotherapist to exclude anxiety-depressive disorder and prescribe therapy aimed at stopping it. She was scheduled to return to the appointment in three months.

On repeated observation, the patient noted that the background of her mood improved, excessive tearfulness and emotional lability disappeared, sexual intercourse ceased to bring the previous discomfort, the burning sensation in the urethra became less intense, and the urge to urinate became less frequent.

Example 4. Patient A., 68 years old. Was inpatient treatment in the urology department. Diagnosis: Prostate cancer T2aN0M0 stage IIa, Glisson 7. Concomitant diseases: stage II hypertension, risk 4. Chronic calculous cholecystitis without exacerbation. Initial cataract of the left eye.

The epidemiological history is calm. Heredity is not burdened.

Complaints of numbness in the perineum, urinary and fecal incontinence, erectile dysfunction, back pain, sometimes blood in the urine.

Medical history. Considers himself sick for about 1 year, when he first had pain and cramps during urination. He was treated for a long time by a urologist at the place of residence with a diagnosis of "Cystitis" without effect. A month ago, TRUS revealed a prostate tumor. A biopsy of the prostate was performed, and adenocarcinoma was detected (Glisson 3 + 4 = 7). Hospitalization in the urological hospital is planned for radical prostatectomy.

Physical examination data. The condition is satisfactory. In the lungs, vesicular breathing, no wheezing, RR 17 per minute, clear, rhythmic heart sounds, blood pressure 140/70 mm Hg. Art., heart rate 69 beats per minute. The abdomen is soft, painless, there are no peritoneal signs. Stool, urine output are normal.

Examination in a chair: the external genitals are formed correctly, according to the male pattern. Per rectum - the bed of the prostate is free, soft, infiltrates are not determined, there is no pain in the study.

Neurological status: cranial nerves without pathology, coordination tests are satisfactory, no paresis, tendon reflexes are symmetrical, no pathological signs, hypesthesia in the area of pudendal innervation on both sides, sacral reflexes are absent, sphincter function is impaired.

In laboratory tests - leukocyturia (up to 15 in the field of view), significant erythrocyturia (completely in the field of view), hypercholesterolemia (6.95 mmol / l), PSA 0.01 ng / ml.

A study was carried out according to the proposed method (the stimulation zone is segmental, the stimulation point is in the center at the level of II-IV sacral vertebrae).

From the right bulbocavernous muscle, the latency of the M-response is 0 ms, from the left bulbocavernous muscle - 0 ms.

M-answers are not received, that is, there is a block of conduction along both pudendal nerves.

From this example, it follows that there is no conduction along the pudendal nerves due to their most probable intraoperative complete injury. The patient was examined again 3 months later, but the pudendal nerve conduction block was again registered.

Example 5. Patient E., 34 years old. Was inpatient treatment in the urology department. Diagnosis: Chronic pelvic pain similar to vulvar pain syndrome. Concomitant diseases: Varicose veins of the lower extremities. Chronic hemorrhoids.

The epidemiological history is calm. Heredity is not burdened.

Complaints of shooting pain in the perineal region to the right of the anus to the clitoris, associated with a sitting position, does not affect sleep and falling asleep, aggravated by sexual intercourse.

Medical history. Considers himself ill for about 6 months, symptoms appeared after uncomplicated childbirth in a natural way. She was treated by a neurologist with insignificant effect with a diagnosis of "Pudendal neuralgia on the right". She was repeatedly consulted by a gynecologist and urologist, no organic pathology was revealed.

Physical examination data. The condition is satisfactory. In the lungs, vesicular breathing, no wheezing, RR 16 per minute, clear heart sounds, rhythmic, blood pressure 120/70 mm Hg, heart rate 77 beats per minute. The abdomen is soft, painless, there are no peritoneal signs. Stool, urine output are normal.

Examination in a chair: the external genitals are formed correctly, according to the female type. Per vaginum - pain on palpation, more on the right, the patient screams in pain.

Neurological status: cranial nerves without pathology, coordination tests are satisfactory, no paresis, tendon reflexes are symmetrical, no pathological signs, allodynia in the perineum on the right, sacral reflexes are preserved, sphincter function is not impaired.

In laboratory tests - the norm.

A study was carried out according to the proposed method (the stimulation zone is segmental, the stimulation point is in the center at the level of II-IV sacral vertebrae).

From the right bulbocavernous muscle, the latency of the M-response was 14.61 ms, from the left bulbocavernous muscle - 12.80 ms. The maximum latency is 14.61 ms, which falls in the range from 13.85 ms to 15.28 ms inclusive, the state is borderline.

Instrumental survey data.

Uroflowmetry: urine volume - 230 ml, Qmax - 31 ml / s, Qav. - 19 ml / s.

Cystoscopy: the urethra is freely passable. Bladder capacity 140 ml. The mucous membrane is clean, pink; mouths on rollers.

Ultrasound of the internal genital artery (transperineal access): the main type of blood flow from both sides, the linear blood flow velocity is not reduced.

MRI of the small pelvis: no abnormalities.

Sighting MRI of Alcock's canal: pudendal nerves and adjacent structures were unremarkable.

A decision was made to monitor the patient after discharge from the hospital, and a return visit was scheduled after 3 months.

After the specified period, a repeated study was carried out according to the proposed method.

From the right bulbocavernous muscle, the latency of the M-response was 13.82 ms, from the left bulbocavernous muscle - 11.98 ms. The maximum latency is 13.82 ms, which is less than 13.85, the norm.

The patient noted a decrease in pain intensity against the background of the recommended therapy.

Clinical cases illustrate the high value of magnetic stimulation in diagnosing lesions of the peripheral neuromotor apparatus in patients with pudendoneuropathies.

In conditions of a large flow of patients, the method makes it possible to differentiate patients into those who need expensive additional examinations (in the case of obtaining values related to pathology), those who do not need them (in the case of obtaining standard indicators) and those who need to be examined more deeply. and be under closer control by doctors (in case of obtaining borderline values).

Unlike other methods, the one proposed by us is non-invasive and allows you to get answers in all cases, which allows you to standardize the results. The method makes it possible to identify the compression of the pudendal nerves in the places of their most probable compression at the early stages of the pathological process, or to verify their dysfunction in iatrogenic damage. The use of surface disposable electrodes makes it possible to standardize the position of electrical potential derivation and makes it possible to reliably receive responses from the muscles innervated by the pudendal nerve, as well as to lateralize responses, i.e., to evaluate separately the right and left pudendal nerves. The method is absolutely painless.

The proposed research methodology can become a component of the algorithm for the study of patients with pudendoneuropathies, and will also allow timely initiation of pathogenetic treatment, monitoring the effectiveness of therapy.

The proposed method makes it possible to assess conduction disturbances along the pudendal nerves more reliably at an early stage of the pathological process and is cheaper than other existing techniques, while being painless and non-invasive.

Claims (4)

1. The method of neurophysiological study of the motor portion of the pudendal nerve in pudendoneuropathies, including neurophysiological study of the response to magnetic stimulation, analysis of the latency of the M-response, characterized in that a magnetic stimulator is used as stimulation equipment, active disposable surface silver chloride is applied to the bulbocavernosus muscles alternately on the right and left the electrode, while in men the electrode is applied to the most protruding areas of the bulbocavernous muscles, determined by palpation, in women - at a distance of 0.5 cm from the entrance to the vagina, along the outer edge of the labia majora, the reference electrode is attached to the inner surface of the thigh of the same name, the center of the magnetic the inductor is placed at the level of II-IV sacral vertebrae in the center, the current in the inductor coil is directed counterclockwise for the right side and clockwise for the left side, the magnetic field power is set to 100%, stimulation is carried out until M-from veta, in the presence of the M-response and the maximum value of the latency of the M-response up to 13.85 ms inclusive, it is considered that the conduction along the pudendal nerves is within the normal range, at values of more than 15.28 ms, it is considered that the conduction is impaired, and with values from 13, 85 ms to 15.28 ms inclusive consider the state to be borderline. 2. The method according to claim 1, characterized in that a Neuro-MS / D magnetic stimulator combined with a Neuro MEP-4 electroneuromyograph, a round inductor 15 cm in diameter, is used for segmental magnetic stimulation. 3. The method according to claim 1, characterized in that surface film silver chloride electrodes are used with a size of 2.2 × 3.4 cm with an adhesive solid medical gel and a contact format pad for attachment to a crocodile connector. 4. The method according to claim 1, characterized in that in the borderline state, the study is repeated after 3 months.