Clinical and electrophysiological studies on sensory conduction mediated by the accessory rootlets of the human trigeminal nerve

1975 ◽  
Vol 42 (5) ◽  
pp. 513-521 ◽  
Author(s):  
Adolfo Ley ◽  
Luis Montserrat ◽  
Fernando Bacci ◽  
Adolfo Ley
Keyword(s):  
Trigeminal Nerve ◽  
Blink Reflex ◽  
Content Type ◽  
Sensory Conduction ◽  
Before And After ◽  
Electrophysiological Studies ◽  
Sensory Fibers ◽  
Sensory Root ◽  
Fine Print ◽  
Stimulation Of

✓ The authors present records of potentials evoked in the roots of the trigeminal nerve by stimulation of its cutaneous branches. Records were made during nine operations for tic douloureux in which the main sensory root of the trigeminal nerve was totally sectioned under the microscope by the transcerebellar route. In every case, the accessory (aberrant) and motor roots were easily identified and spared. Records before and after total main sensory root division showed persistence of evoked potentials in the aberrant and motor fibers. Partial preservation of sensation and blink reflex in these cases reinforced the impression that there is somatic sensory conduction through true aberrant sensory fibers running between the motor and main sensory roots.

Transcorneal stimulation of trigeminal nerve afferents to increase cerebral blood flow in rats with cerebral vasospasm: a noninvasive method to activate the trigeminovascular reflex

2002 ◽  
Vol 97 (5) ◽  
pp. 1179-1183 ◽  
Author(s):  
Basar Atalay ◽  
Hayrunnisa Bolay ◽  
Turgay Dalkara ◽  
Figen Soylemezoglu ◽  
Kamil Oge ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cerebral Vasospasm ◽  
Trigeminal Nerve ◽  
Nerve Endings ◽  
Noninvasive Method ◽  
Direct Stimulation ◽  
Content Type ◽  
Fine Print ◽  
Stimulation Of

Object. The goal of this study was to investigate whether stimulation of trigeminal afferents in the cornea could enhance cerebral blood flow (CBF) in rats after they have been subjected to experimental subarachnoid hemorrhage (SAH). Cerebral vasospasm following SAH may compromise CBF and increase the risks of morbidity and mortality. Currently, there is no effective treatment for SAH-induced vasospasm. Direct stimulation of the trigeminal nerve has been shown to dilate constricted cerebral arteries after SAH; however, a noninvasive method to activate this nerve would be preferable for human applications. The authors hypothesized that stimulation of free nerve endings of trigeminal sensory fibers in the face might be as effective as direct stimulation of the trigeminal nerve. Methods. Autologous blood obtained from the tail artery was injected into the cisterna magna of 10 rats. Forty-eight and 96 hours later (five rats each) trigeminal afferents were stimulated selectively by applying transcorneal biphasic pulses (1 msec, 3 mA, and 30 Hz), and CBF enhancements were detected using laser Doppler flowmetry in the territory of the middle cerebral artery. Stimulation-induced changes in cerebrovascular parameters were compared with similar parameters in sham-operated controls (six rats). Development of vasospasm was histologically verified in every rat with SAH. Corneal stimulation caused an increase in CBF and blood pressure and a net decrease in cerebrovascular resistance. There were no significant differences between groups for these changes. Conclusions. Data from the present study demonstrate that transcorneal stimulation of trigeminal nerve endings induces vasodilation and a robust increase in CBF. The vasodilatory response of cerebral vessels to trigeminal activation is retained after SAH-induced vasospasm.

Observations on synkinesis in patients with hemifacial spasm

1984 ◽  
Vol 60 (4) ◽  
pp. 821-827 ◽  
Author(s):  
Phyo Kim ◽  
Takanori Fukushima
Keyword(s):  
Hemifacial Spasm ◽  
Blink Reflex ◽  
Vascular Compression ◽  
Pathophysiological Mechanism ◽  
Unaffected Side ◽  
Content Type ◽  
Stapedius Muscle ◽  
Before And After ◽  
Reversible Condition ◽  
Fine Print

✓ In 95 patients with hemifacial spasm, synkinetic actions were measured objectively using electromyographic examination of the blink reflex and impedance audiometry. Abnormal synkinesis between the orbicularis oculi and the orbicularis oris muscles was recorded in 93% of cases, while synkinesis between the stapedius muscle and the facial muscles was recorded in 87%. Neither of these effects could be demonstrated on the unaffected side. The examinations were performed before and after microvascular decompression in 66 cases. Rapid disappearance of synkinesis, often within 10 days, was observed after the relief of vascular compression in 81% of patients who had not undergone previous peripheral facial nerve block procedures. These findings indicate that the synkinesis seen in hemifacial spasm is essentially a reversible condition, and suggest that axonal ephaptic conduction at the vascular compression site plays an important role in the pathophysiological mechanism of hemifacial spasm.

Detailed anatomy of the intracranial portion of the trigeminal nerve

1971 ◽  
Vol 35 (5) ◽  
pp. 592-600 ◽  
Author(s):  
Kristin Gudmundsson ◽  
Albert L. Rhoton ◽  
Joseph G. Rushton
Keyword(s):  
Posterior Fossa ◽  
Trigeminal Nerve ◽  
Sensory Loss ◽  
Content Type ◽  
The Third ◽  
Trigeminal Nerves ◽  
Motor Root ◽  
Sensory Root ◽  
Fine Print

✓ Fifty trigeminal nerves were studied at autopsy under various magnifications. Two findings that could explain the preservation of sensation after rhizotomy of the main sensory root are: 1) anastomosis between the motor and sensory root in the majority of nerves, and 2) aberrant sensory rootlets that arose from the pons separately from the main sensory root in one half of the nerves. The motor root is composed of as many as 14 separately originating rootlets that usually join about 1 cm from the pons. At the pontine level, the first division fibers are usually dorsomedial and the third division fibers caudolateral within the main sensory root. However, the third division fibers may vary from being almost directly lateral to directly caudal to the first division fibers. This may explain the variability of sensory loss with partial section in the posterior fossa.

Nerve cells in the intracranial part of the trigeminal nerve of man and dog

1971 ◽  
Vol 34 (5) ◽  
pp. 643-646 ◽  
Author(s):  
Kamal Mousa Mira ◽  
Ibrahiem Abou Elnaga ◽  
Hassanein El-Sherif
Keyword(s):  
Trigeminal Nerve ◽  
Proximal Part ◽  
Nerve Fibers ◽  
Nerve Cells ◽  
Content Type ◽  
Specific Location ◽  
Nerve Bundles ◽  
Motor Root ◽  
Sensory Root ◽  
Fine Print

✓ Nerve cells histologically similar to the ganglionic cells of the trigeminal nerve were observed in the proximal part of the sensory root and in the motor root of the human trigeminal nerve. They were also seen in the sensory root of the trigeminal nerve of the dog. Counting of the nerve fibers showed doubling of the number of nerve fibers in the three divisions compared with the fibers in the sensory root adjacent to the trigeminal ganglion. There was also an increase in the number of fibers within the sensory root as it courses centrally, while a decrease was seen in the number of fibers in the proximal part of the motor root. Intermediate nerve bundles were seen leaving the motor root near the pons and joining the sensory root centrally. The fibers of the sensory root corresponding to each peripheral division maintained their specific location in the sensory root during the whole course centrally.

Trigeminal neuralgia associated with seizure and syncope

1984 ◽  
Vol 61 (3) ◽  
pp. 594-595 ◽  
Author(s):  
Wishwa N. Kapoor ◽  
Peter J. Jannetta
Keyword(s):  
Trigeminal Neuralgia ◽  
Trigeminal Nerve ◽  
Mechanical Stimulation ◽  
Microvascular Decompression ◽  
Facial Pain ◽  
Loss Of Consciousness ◽  
Content Type ◽  
Vascular Decompression ◽  
Fine Print ◽  
Stimulation Of

✓ A patient with trigeminal neuralgia experienced a generalized seizure and a prolonged syncopal episode. He was found to be asystolic during the syncopal episode. There was no recurrence of loss of consciousness after implantation of a pacemaker. Mechanical stimulation of the trigeminal nerve during craniotomy for microvascular decompression of the trigeminal nerve resulted in bradycardia. Since vascular decompression of the trigeminal nerve, there has been no recurrent facial pain, and no further syncope, seizures, or bradycardia. Syncope and seizures have not been previously reported in association with trigeminal neuralgia, although they are well described with glossopharyngeal neuralgia.

Detailed anatomy of the motor and sensory roots of the trigeminal nerve and their neurovascular relationships: a magnetic resonance imaging study

2004 ◽  
Vol 101 (3) ◽  
pp. 427-434 ◽  
Author(s):  
Indra Yousry ◽  
Bernhard Moriggl ◽  
Markus Holtmannspoetter ◽  
Urs D. Schmid ◽  
Thomas P. Naidich ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Trigeminal Nerve ◽  
Mr Angiography ◽  
Three Dimensional ◽  
Content Type ◽  
Cerebellar Artery ◽  
Motor Root ◽  
Sensory Root ◽  
Angiography Sequences ◽  
Fine Print

Object. The trigeminal nerve conducts both sensory and motor impulses. Separate superior and inferior motor roots typically emerge from the pons just anterosuperomedial to the entry point of the sensory root, but to date these two motor roots have not been adequately displayed on magnetic resonance (MR) images. The specific aims of this study, therefore, were to identify the superior and inferior motor roots, to describe their exact relationship to the sensory root, and to assess the neurovascular relationships among all three roots of the trigeminal nerve. Methods. Thirty-three patients and seven cadaveric specimens (80 sides) were studied using three-dimensional (3D) Fourier transform constructive interference in steady-state (CISS) imaging. The 33 patients were also studied by obtaining complementary time-of-flight (TOF) MR angiography sequences with and without contrast enhancement. At least one motor root was identified in all sides examined: in 51.2% of the sides a single motor root, in 37.5% two motor roots, and in 11.2% three motor roots. The superior cerebellar artery (SCA) and the anterior inferior cerebellar artery (AICA) contacted the sensory root in 45.5% of patients and 42.9% of specimens. The SCA often contacted the superior motor root (48.5% of patients and 50% of specimens) and less frequently the inferior motor root (26.5% of patients and 20% of specimens). Conclusions. Three-dimensional CISS and complementary 3D TOF MR angiography sequences reliably display sensory, superior motor, and inferior motor roots of the trigeminal nerve and their relationships to the SCA and AICA.

Electrical stimulation of the trigeminal nerve root for the treatment of chronic facial pain

1995 ◽  
Vol 83 (1) ◽  
pp. 72-78 ◽  
Author(s):  
Ronald F. Young
Keyword(s):  
Electrical Stimulation ◽  
Pain Intensity ◽  
Trigeminal Nerve ◽  
Nerve Root ◽  
Facial Pain ◽  
Content Type ◽  
Number Of Patients ◽  
Trigeminal Nerve Root ◽  
Fine Print ◽  
Stimulation Of

✓ Between March 1990 and December 1992, 23 patients with chronic intractable facial pain due to various forms of injury to the trigeminal nerve or nerve root underwent implantation of an electrical stimulating system to treat their pain. All patients had failed previous extensive pain treatment efforts. A monopolar platinum-iridium electrode was implanted on the trigeminal nerve root via percutaneous puncture of the foramen ovale. All patients experienced at least 50% reduction in pain intensity during a period of trial stimulation and underwent internalization of the electrode and connection to a completely implanted pulse generator. Independent assessment of the effect of stimulation was obtained by a specially trained nurse practitioner. Over a mean follow-up period of 24 months, six patients reported nearly complete relief of pain and six others reported at least a 50% reduction in pain intensity using a visual analog scale. Thus, 12 (52%) of the 23 patients achieved 50% or greater reduction in pain intensity. Although changes in the patterns of analgesic medication usage were few, six patients (26%) now experience a normal life style. Only one complication was seen, namely a dislocated electrode, which was easily replaced. Chronic electrical stimulation of the trigeminal nerve root appears to be an easy and safe technique for providing relief of chronic facial pain related to injury to the trigeminal nerve in a significant number of patients.

Surgical treatment of cluster headache

1990 ◽  
Vol 72 (6) ◽  
pp. 866-871 ◽  
Author(s):  
Joel C. Morgenlander ◽  
Robert H. Wilkins
Keyword(s):  
Surgical Treatment ◽  
Cluster Headache ◽  
Trigeminal Nerve ◽  
Microvascular Decompression ◽  
Content Type ◽  
Pain Pathways ◽  
Autonomic Disturbances ◽  
Sensory Root ◽  
Fine Print ◽  
Nervus Intermedius

✓ Cluster headache is ordinarily managed medically, but may become refractory to such medical management. In this setting, surgical treatment has occasionally been performed, based on evidence that pertinent pain pathways and parasympathetic pathways may be interrupted at the main sensory root of the trigeminal nerve and at the nervus intermedius. Between 1976 and 1987, 13 patients underwent surgery for treatment of cluster headache that was refractory to medical therapy (15 procedures). Partial sectioning of the main sensory root and sectioning of the nervus intermedius were performed in nine patients; only partial sectioning of the main sensory root in one; only sectioning of the nervus intermedius in one; and nervus intermedius sectioning plus microvascular decompression of the trigeminal nerve in two. The average postoperative period for the 13 patients was 37 months (range 2 to 135 months). All patients had return of their headaches postoperatively except for one patient who obtained relief after a repeat procedure. Headache began to return between 2 days and 2 years postoperatively. Three patients are currently free of headache, including both patients who had nervus intermedius sectioning plus microvascular decompression of the trigeminal nerve. Together with recurrence of headache, cluster-associated autonomic disturbances recurred after 14 of the 15 operations but are currently absent in the three headache-free patients. Partial sectioning of the main sensory root and sectioning of the nervus intermedius, as performed in these patients, seem to have limited value in the treatment of cluster headache.

Trigeminocardiac reflex during surgery in the cerebellopontine angle

1999 ◽  
Vol 90 (2) ◽  
pp. 215-220 ◽  
Author(s):  
Bernhard Schaller ◽  
Rudolf Probst ◽  
Stephan Strebel ◽  
Otmar Gratzl
Keyword(s):  
Trigeminal Nerve ◽  
Cerebellopontine Angle ◽  
Experimental Studies ◽  
Ocular Surgery ◽  
Content Type ◽  
Trigeminocardiac Reflex ◽  
Arterial Blood ◽  
Nerve System ◽  
Fine Print ◽  
Stimulation Of

Object. In different experimental studies authors have analyzed the autonomic responses elicited by the electrical, mechanical, or chemical stimulation of the trigeminal nerve system. The trigeminocardiac reflex (TCR) is a well-recognized phenomenon that consists of bradycardia, arterial hypotension, apnea, and gastric hypermotility. It occurs during ocular surgery and during other manipulations in and around the orbit. Thus far, it has not been shown that central stimulation of the trigeminal nerve can also cause this reflex.Methods. The TCR was defined as clinical hypotension with a drop in mean arterial blood pressure (MABP) of more than 20% and bradycardia lower than 60 beats/minute. Pre-, intra-, and postoperative heart rate (HR) and MABP were reviewed retrospectively in 125 patients who underwent surgery for tumors of the cerebellopontine angle (CPA), and they were divided into two groups on the basis of the occurrence of the TCR during surgery. Of the 125 patients, 14 (11%) showed evidence of the TCR during dissection of the tumor near the trigeminal nerve at the brainstem. Their HRs fell 38% and their MABPs fell 48% during operative procedures as compared with preoperative levels. After cessation of manipulation, the HRs and the MABPs returned to preoperative levels. Risk factors for the occurrence of the TCR were compared with results from the literature.Conclusions. The authors' results show the possibility of occurrence of a TCR during manipulation of the central part of the trigeminal nerve when performing surgery in the CPA.

Referral of pain from dural stimulation in man

1971 ◽  
Vol 34 (5) ◽  
pp. 630-642 ◽  
Author(s):  
F. P. Wirth ◽  
J. M. Van Buren
Keyword(s):  
Trigeminal Nerve ◽  
Cervical Spinal Cord ◽  
Referred Pain ◽  
Referral Pattern ◽  
Central Projections ◽  
Content Type ◽  
Spinal Nerves ◽  
Implanted Electrodes ◽  
Fine Print ◽  
Stimulation Of

✓ Electrical stimulation of the dura was carried out in 25 patients using chronically implanted electrodes to determine areas of referred pain. Referred pain occurred over areas supplied by all divisions of the trigeminal nerve and the upper three cervical spinal nerves. No pattern of pain referral could be established on the basis of electrode positions determined from bone landmarks on the skull. It is suggested that these findings may be explained either by a greater overlap of the dural nerves than had been previously recognized, or by an overlap of the connections of the cervical nerves and the trigeminal nerve in the dorsal horn of the cervical spinal cord. Both of these mechanisms seem to be operative to some degree. Bilateral and contralateral pain was also elicited; whether this was due to stimulation of the bilateral termination of the dural nerves near the midline or of the bilateral central projections of these dural nerves is not clear. Contralateral referral of pain from dural points widely separated from the midline, however, suggests that some contralateral central projections do exist. The authors conclude that head pain of dural origin has limited clinical usefulness because of the lack of consistent specificity in its referral pattern.

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