RU2438578C1 - Method of trigeminal nerve neuralgia diagnostics - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medicine, particularly to neurology. Spiral computer angiography is performed, its results used in determination of superior cerebellar artery position against Merkel's fossa. If the top of superior cerebellar artery loop is higher than posterior edge of Merkel's fossa by 2 mm or less, classic neuralgia of trigeminal nerve is diagnosed.

EFFECT: increased reliability of diagnostics of classic trigeminal nerve neuralgia due to the bone reference mark with permanent location.

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Description

The present invention relates to medicine, namely to neurology, and may find application for the diagnosis of classical trigeminal neuralgia.

Trigeminal neuralgia (NTN) is characterized by severe bouts of excruciating pains in the face that occur when talking, eating, shaving, washing, etc. The intensity and frequency of seizures, often reaching 100 or more per day, leads patients to despair, sometimes to attempts suicide (Puzin M.N. Facial pain. M: RUDN, 1992. - p. 81-83; Stepanchenko A.V. Typical trigeminal neuralgia. M: VHM, 1994 - p. 12; Eller JL Stubhang A Trigeminal neuralgia: definition and classification. // Neurosurg. Focus. - 2005, Vol. 18, N5. - P.63; Caminero AB, Mateos V. A clinical approach to cranial neuralgias. Rev Neurol. 2009. Vol. 48, N7. - P.363-365).

Currently, trigeminal neuralgia is divided into classic and symptomatic. The Headache Classification Committee of the International Headache Society // Cephalagia - 1988. - N7 - P.65-73; The International Headache Society (HIS) considers the trigeminal neuralgia a classic neuralgia due to a neurovascular conflict. Peter J. Jannetta, et al. Technique of microvascular decompression. Neurosurg. Focus, 2005, V.18, N1. P.1-5). Symptomatic or secondary trigeminal neuralgia is considered neuralgia due to various pathological processes: tumors, arteriovenous aneurysms, multiple sclerosis, cysts, trauma of the trigeminal nerve and its branches, brain development abnormalities, etc. (Gnanalingham K., Joshi SM, Lopez B. et al et. Trigeminal neuralgia secondary to Chiari's malformation-triatment with ventriculoperitoneal shunt // Surg. Neurol - 2005 - Vol.63, N6 - P.586-588; Gass A., Ketchen N., MacManus DG et al. Trigeminal neuralgia in patients with multiple sclerosis: lesion localization with magnetic resonance imaging // Neurology.- 1997 - Vol.49, N4 - P.1142-1144; Barker 2 ^nd FG, Jannetta PJ, Babu DP et al. Long-term outcome after operation for trigeminal n euralgia in patients with posterior fossa tumors // J. Neurosurg., 1995. - Vol. 84, N5. - P.818-825).

The lack of effective diagnostic methods does not allow timely diagnosis of NTN, and therefore - to begin timely treatment in the early stages of the disease. The intensity of the pain is such that the patient is deprived of the joy of life, often of disability, and all his interests are confined to excruciating pain. Therefore, the development of new, effective methods for diagnosing trigeminal neuralgia is an urgent problem of modern medicine (A. Irasek. Pain Surgery // Czechoslovakia: Atria, 1958, P.13-15; Grachev Yu.V. Pathogenetic mechanisms and clinical features of trigeminal facial pain / / Journal of neurologist and psychiatrist named after S.S. Korsakov. - 1999. - T. 99, No. 8. - P. 38-42; Love S. Trigeminal neuralgia: pathology and pathogenesis / Brain. - 2002. - Vol. 125, N 3 - P.687).

Studies on the medical, scientific and patent literature have revealed various methods for the diagnosis of trigeminal neuralgia.

Thus, the USSR Author's Certificate No. 1674804 (1991, BI No. 33) protected the “Method for the diagnosis of trigeminal nerve damage”, which includes registration and analysis of somatosensory evoked potentials of the healthy and affected sides. The evoked potentials are recorded for stimulation of the exit points of the I, II and III branches of the trigeminal nerve, components of the 3-9 ms range are analyzed and, when their amplitude decreases by more than 15%, they are diagnosed with an extracranial response in one of the branches, and an intracranial level in the responses of all three branches defeat.

The disadvantages of the method is its lack of reliability, due to the fact that with its help it is problematic to distinguish between classical NTN and symptomatic, i.e. caused either by trauma, or herpetic damage to the branches of the nerve, or compression of the root of the trigeminal nerve, a tumor or other volume formations.

In the patent of the Russian Federation No. 2069971 (1996, BI No. 34) described used for the diagnosis, in particular, trigeminal neuralgia "Method for assessing the function of the motor portion of the trigeminal nerve", which provides stimulation of the nerve in the submandibular region at the angle of the lower jaw. An evoked response is recorded from the anterior abdomen of the biceps muscle. The pronounced difference in the amplitudes of responses on the intact and affected side allows us to diagnose the axonal type of nerve damage, and the difference in latent periods indicates a slowdown in the spread of excitation along the nerve from the affected side.

The disadvantages of the method are its lack of reliability, due to the fact that the information obtained does not allow to distinguish between classical NTN and symptomatic.

RF patent No. 2111701 (1998, BI No. 15) protected "Method for diagnosing the state of the infraorbital canal in patients with trigeminal neuralgia." Before tomography, a water-soluble radiopaque substance is introduced into the lumen of the channel, the distance between the neurovascular bundle and the walls of the channel and the distance of the lumen of the channel are determined. By narrowing the lumen of the channel to 2-2.5 mm, compression on the infraorbital nerve is diagnosed.

The disadvantages of the method is the presence of radiation exposure to patients and medical staff, as well as the limited functionality of the method, with which it is almost impossible to diagnose NTN.

In the patent of the Russian Federation No. 2125830 (1996, BI No. 4), a method for diagnosing lesions of the facial nerve, the cortical-nuclear pathway of the facial nerve and the first branch of the trigeminal nerve is described, which involves the study of the blinking reflex by electrocutaneous stimulation. Additionally, a blinking reflex is recorded during magnetic stimulation of the motor cortex. With latency indices of the first component of the blinking reflex during magnetic stimulation (16.1 ± 0.7) ms, and electrocutaneous stimulation of more than 15.3 ms, damage to the first branch of the trigeminal nerve is diagnosed.

RF patent No. 2185092 (2002, BIPM No. 21) protected "Method for the diagnosis of lesions of the first and second branches of the trigeminal nerve." Alternately electrical stimulation of the supraorbital nerve and infraorbital nerve is performed. The components of the blinking reflex are recorded. The latent periods of the first components of the blinking reflex are analyzed. With an increase in the latent period of the first component of the blinking reflex, a lesion of the first or second branches of the trigeminal nerve is diagnosed on the side of the increase in the latent period.

In the patent of the Russian Federation No. 2309669 (2007, BIPM No. 31), a "Method for diagnosing the functional state of the first and second branches of the trigeminal nerve, facial nerve and afferent pathways of the brain" is described. A study of the blink reflex is carried out by electrical stimulation of the supraorbital nerve, infraorbital nerve. A study is also being made of the motor response of the circular muscle of the eye during magnetic stimulation of the medulla oblongata. For an isolated increase in latent periods of recorded early responses of the blinking reflex and motor responses of the circular muscle of the eye, differential diagnosis of lesions of the I and II branches of the trigeminal nerve is carried out.

The disadvantages of the above methods are their complexity, due to the need for specialized sophisticated and expensive equipment, as well as their lack of reliability and limited functionality, because, firstly, the first branch of the trigeminal nerve is affected in no more than 2% of the total number of patients with NTN, and the vast majority of patients - over 80%, suffer from a defeat of the third branch (V. A. Smirnov. Diseases of the nervous system of the face - M .: Medicine, 1976, p. 61; Afanasyeva E.V. Trigeminal neuralgia nerve / Rostov-on-Don, 2008, p. 103), secondly, an increase in the latent period of the component of the blinking reflex can occur both in classical and symptomatic NTN caused by various pathological processes, and, thirdly, with with their help, it is practically impossible, when making a diagnosis, to distinguish between classical NTN and symptomatic.

The closest technical solution adopted for the prototype is a method for the diagnosis of trigeminal neuralgia described in Miller JP, Acar F, Hamilton BE, Burchiel K.J. Radiographic evaluation of trigeminal neurovascular compression in patients with and without trigeminal neuralgia. J Neurosurg. 2009. Vol. 110, N4, P.627-632.

The essence of the method lies in the fact that the patient undergoes magnetic resonance imaging with contrasting cerebral vessels and subsequent reconstruction of the 3 D image of the trigeminal nerve with structures adjacent to it. If there is contact of the trigeminal nerve with the superior cerebellar artery, classic trigeminal neuralgia is diagnosed.

The disadvantages of the prototype are the lack of reliability of the method, due to the fact that according to the authors of the prototype in 17% of cases, the trigeminal nerve contact with the superior cerebellar artery occurs in healthy people who do not suffer from NTN.

The aim of the invention is to increase the reliability of diagnosis of classical trigeminal neuralgia.

This goal is achieved by the fact that the patient performs spiral computed angiography (SKA) with contrasting cerebral vessels. According to the results of SKA, the position of the superior cerebellar artery (VMA) relative to the mekel fossa (MY) is determined. If the top of the VMA loop is located no higher than 2 mm relative to the posterior edge of the MN, classic NTN is diagnosed.

The theoretical justification of the method is that in the region of the posterior margin of the MY, the thickness of the trigeminal nerve root (CTN) is 2.5 ± 0.5 mm (Afanasyeva E.V. Trigeminal neuralgia / Rostov-on-Don, 2008, p.5- 8), while the posterior margin of the MN is a reliable “bone” one, not shifted by a reference point determining the position of the root of the trigeminal nerve relative to the top of the VMA loop. Since, in healthy individuals, the top of the VMA loop is located in the space between CTN and the cerebellum, 2.5-3 mm higher than the posterior margin of the MJ, the criterion for the diagnosis of classical NTN due to neurovascular conflict, it is proposed to consider the location of the top of the VMA loop not higher than 2 mm relative to an unshifted landmark - the back edge of ME.

Detailed description of the method

A patient using, for example, a Briliance CT 64 slice spiral computed tomography scanner (Philips Medical Systems) performs spiral computed angiography (SCA) - a spiral scan with bolus contrasting of cerebral vessels. The cut thickness for bolus contrasting is 0.9 mm, the increment is 0.45, and the scanning time is 5-6 seconds. The rate of administration of the drug is 4.5 ml / s, the volume of the administered drug is 50 ml, the drug used: ultravist - 370. The results of SKA are processed on a computer using image processing programs: MIP, SSD (3D). Assessment of the position of the top of the loop VMA produce relative to the rear edge of the MJ. If the apex of the right and / or left VMA loop is located no higher than 2 mm relative to the posterior edge of the corresponding MN, the classic right, left, or bilateral NTN is diagnosed, which is caused by a neurovascular conflict.

The practical feasibility of the proposed method is illustrated by examples from clinical practice.

Example 1: patient G., 70 years old, medical history No. 2248/261 was admitted to the neurosurgery clinic of the Rostov State Medical University (Rostov State Medical University) with complaints of sharp pains in the right frontal region that first appeared 5 years ago without apparent reason. The duration of the attack ranged from a few seconds to 1-2 minutes with a frequency of up to 20-30 attacks per day. Against the background of taking 400-600 mg of finlepsin, remission occurred for several months. Each subsequent exacerbation of pain was accompanied by an increase in seizures and an increase in their duration to 3 minutes. After severe stress over the past year, seizures have become permanent.

For the diagnosis of the patient was examined according to the claimed method.

Using a Briliance CT 64 slice spiral computed tomography scanner (Philips Medical Systems), spiral computed angiography (SCA), a spiral scan with bolus contrasting of cerebral vessels, was performed. The cut thickness for bolus contrasting is 0.9 mm, the increment is 0.45, the scan time is 5 seconds. The rate of administration of the drug is 4.5 ml / sec, the volume of the administered drug is 50 ml, the drug used: ultravist - 370. The results of SKA were processed on a computer. Using the image processing program SSD (3D), the position of the VMA relative to the ME was determined. The position of the top of the loop of the VMA was estimated relative to the posterior edge of the MJ. Since the apex of the loop of the right VMA was located 4 mm lower relative to the posterior edge of the right MJ, and the apex of the loop of the left VMA was located 5 mm above the posterior edge of the left MJ, the patient was diagnosed with classic right-sided NTN due to neurovascular conflict.

The operation was recommended for the patient: microvascular decompression of CTN, during which using a video camera it was recorded that indeed the top of the loop of the right VMA was located 4 mm below the posterior edge of the right MJ, which means below the upper edge of the CTN, which has a thickness of 2.5 in this place mm i.e. there really was a neurovascular conflict. Thus, intraoperatively, the diagnosis according to the claimed method was confirmed: classic right-sided NTN. After the operation to eliminate the neurovascular conflict, the pain in the patient disappeared.

Example 2: Patient R., 55 years old, medical history No. 006073/775 was admitted to the neurosurgery clinic of Rostov State Medical University with complaints of paroxysmal pain of a shooting character in the left half of the face, mainly in the lower jaw. Sick for more than three years. Attacks of pain were provoked by eating, talking, using the toilet of the oral cavity and face. The duration of seizures is up to 3 minutes with a frequency of more than 10 per day. On the background of taking finlepsin, remission occurred for 6-8 months. The duration of the last exacerbation is about 4 months. Taking finlepsin at a dose of 1600 mg per day did not bring relief.

For the diagnosis of the patient was examined according to the claimed method.

Using a Briliance CT 64 slice spiral computed tomography scanner (Philips Medical Systems), spiral computed angiography (SCA), a spiral scan with bolus contrasting of cerebral vessels, was performed. The cut thickness for bolus contrasting is 0.9 mm, the increment is 0.45, the scan time is 5 seconds. The drug was administered at a rate of 4.5 ml / s, the drug was injected at a volume of 50 ml, and the drug used was: ultravist - 370. The results of SKA were processed on a computer. Using the image processing program SSD (3D), the position of the VMA relative to the MN was determined. The position of the top of the loop of the VMA was estimated relative to the posterior edge of the MJ. Since the apex of the loop of the right VMA was located 4 mm above the posterior edge of the right MJ, and the apex of the loop of the left VMA was located at the level of the rear edge of the left MJ, the patient was diagnosed with classic left-sided NTN due to neurovascular conflict.

The operation was recommended for the patient: microvascular decompression of CTN, during which using a video camera it was recorded that indeed the top of the loop of the left BMA was located at the level of the posterior edge of the left MJ, which means below the upper edge of the CTN, which has a thickness of 3.0 mm in this place, those. there really was a neurovascular conflict. Thus, the diagnosis made according to the claimed method was confirmed intraoperatively: classic left-side NTN. After the operation to eliminate the neurovascular conflict, the pain in the patient disappeared.

According to the proposed method, in the neurosurgery clinic of Rostov State Medical University, 15 patients were examined with complaints of prolonged pain in the face. All patients were diagnosed with classical trigeminal neuralgia due to neurovascular conflict, and surgery was recommended. In all patients, the diagnosis made according to the claimed method was confirmed intraoperatively: classical NTN.

Thus, the proposed diagnostic method can significantly increase the reliability of the diagnosis of classical NTN.

Claims (1)

A method for the diagnosis of trigeminal neuralgia (NTN) by contrasting cerebral vessels, characterized in that the patient undergoes a spiral computed angiography, the results of which determine the position of the superior cerebellar artery (VMA) relative to the meckel fossa (MY), and if the tip of the VMA loop is not located above 2 mm relative to the posterior margin of the MJ, classic NTN is diagnosed.