Resolution of isolated unilateral hypoglossal nerve palsy following microvascular decompression of the intracranial vertebral artery

Hemilingual spasm treated with microvascular decompression of the posterior inferior cerebellar artery: illustrative case

BACKGROUND

Hemilingual spasm (HLS) is an extremely rare condition that induces persistent paroxysms of unilateral tongue spasms with associated speech impairment and pain. Although neurovascular compression has been implicated in its pathogenesis, case accumulation to date has been very limited, with even fewer instances of successful therapy via microvascular decompression (MVD) described. The authors report the second case of HLS treated with MVD and the first such treatment for HLS attributable to posterior inferior cerebellar artery (PICA) compression of the hypoglossal nerve rootlets.

OBSERVATIONS

A 62-year-old woman presented with approximately 15 years of severe, persistent, and painful right tongue spasms and fasciculations. Numerous medical, psychiatric, and interventional treatments had failed to provide relief. MRI revealed likely neurovascular compromise of the right hypoglossal rootlets by the ipsilateral PICA, and MVD was recommended. Intraoperative electromyography (EMG) demonstrated pretreatment pulsatile myotonic discharges, which resolved completely after decompression. The patient recovered very well and, as of the 3-month postoperative follow-up, had complete resolution of painful spasms and approximately 70% reduction in the frequency of nonpainful fasciculations.

LESSONS

MVD is a safe and effective treatment for patients with medically refractory HLS. Intraoperative EMG provides valuable insight into successful decompression; however, further investigation is required to validate this finding. https://thejns.org/doi/10.3171/CASE24869.

Hypoglossal Nerve Neuropathies-Analysis of Causes and Anatomical Background

The hypoglossal nerve is the last, and often neglected, cranial nerve. It is mainly responsible for motor innervation of the tongue and therefore the process of chewing and articulation. However, tumors, aneurysms, dissections, trauma, and various iatrogenic factors such as complications after surgeries, radiotherapy, or airway management can result in dysfunction. Correct differential diagnosis and suitable treatment require a thorough knowledge of the anatomical background of the region. This review presents the broad spectrum of hypoglossal neuropathies, paying particular attention to these with a compressive background. As many of these etiologies are not common and can be easily overlooked without prior preparation, it is important to have a comprehensive understanding of the special relations and characteristic traits of these medical conditions, as well as the most common concomitant disorders and morphological traits, influencing the clinical image. Due to the diverse etiology of hypoglossal neuropathies, specialists from many different medical branches might expect to encounter patients presenting such symptoms.

Isolated hypoglossal nerve neuropathy in vertebral dolichoectasia: Microvascular decompression by vessel transposition with Teflon cuff

Background:

A clinical case of isolated unilateral hypoglossal nerve (HN) neuropathy, which spontaneously occurred from vertebral artery dolichoectasia and was cured by a new method of microvascular decompression by transposition of the vertebral artery using the Teflon cuff.

Case Description:

A young patient with an anamnesis of the disease for more than 4 years and complaints of a deviation of the tongue to the right and dysarthria was examined. MRI of the brain revealed compression of the medulla oblongata by an elongated, dilated, and deformed right vertebral artery. Compression of the medulla oblongata and HN was confirmed during surgery. A transposition of the vertebral artery was performed using a Teflon cuff in the ventral direction to the clivus. Three months after surgery, positive dynamics was noted in the form of regression of dysarthria and improvement of mobility and trophic language.

Conclusion:

Thus, isolated HN neuropathy as a result of compression by an elongated, dilated, and deformed vertebral artery is a rare neurological disease that can be successfully treated by transposition using a Teflon cuff.

Unilateral isolated hypoglossal nerve palsy due to pathologically adherent PICA fusiform aneurysm - A case report

Background:

Isolated hypoglossal nerve palsy due to mechanical compression by a vascular lesion is rare.

Case Description:

We report the case of a 72-year-old man who presented with a 4-year history of swallowing disturbance and subsequently progressively worsening left-sided tongue atrophy. He was referred to our department by a neurologist due a magnetic resonance imaging detected left vertebral artery compression of the medulla. Neurological examination was unremarkable except for left hypoglossal nerve dysfunction, which presented as left-sided atrophy and impaired movement of the tongue. Three-dimensional computed tomography angiography showed proximal left posterior inferior cerebellar artery (PICA) origin fusiform aneurysm. Microvascular decompression was done through a left transcondylar fossa approach. Intraoperative findings were thickened arachnoid around the lower cranial nerves, fusiform aneurysm of the left PICA at its origin from the left vertebral artery which was severely adherent to and compressing the left hypoglossal nerve rootlets.

Conclusion:

The PICA has a very close relationship to the hypoglossal nerve, and its fusiform dilatation could cause isolated hypoglossal nerve dysfunction. Pathological adhesions between hypoglossal rootlets and the PICA aneurysm wall could be a possible contributor in the development and progression of hypoglossal nerve palsy.

Microvascular decompression for hypoglossal nerve palsy secondary to vertebral artery compression: A case report and review of the literature

Background:

Neurovascular-compression syndrome (NCS) is described as a prominent pathological contact between cranial nerves and vessels. Trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia are typical clinical entities associated with NCS. On the other hand, the hyoglossal nerve is rarely affected by NCS.

Case Description:

We present a case of hypoglossal nerve palsy (HNP) secondary to vertebral artery (VA) compression. A 47-year-old man presented to our hospital with a 1-month history of dysarthria and dysphagia. Neurological examination revealed left HNP, with an intact swallowing reflex and no oropharyngeal or palatal weakness. Magnetic resonance imaging (constructive interference in steady state) revealed left hypoglossal nerve compression by the V4 segment of the left atherosclerotic VA. He underwent microvascular decompression (MVD) surgery. Intraoperatively, the VA was compressing the hypoglossal nerve. The left VA was moved and attached to the dura matter using a polytetrafluoroethylene (Teflon®) sheet and fibrin glue. Postoperatively, the patient exhibited gradual recovery of HNP in 3 months without dysfunction of lower cranial nerves.

Conclusion:

In patients with isolated HNP, vascular compression should be considered as a cause of these symptoms, and subsequent MVD can lead to resolution.

Nerve afflictions of maxillofacial region: a report of two cases

Neurological disorders and conditions affecting the maxillofacial region result in disabilities that affect an individual's functioning. Sensory or motor disturbances of the nerves may be caused by trauma, infections, pressure effect or infiltration by tumours or other health conditions. Two rare cases of nerve afflictions are described here with their typical clinical features. The first case had an involvement of maxillary, mandibular and ophthalmic divisions of the trigeminal nerve (sensory) due to herpes zoster infection in a very young patient and the second case had a unilateral isolated hypoglossal nerve palsy (motor) secondary to infiltration of the nerve by carcinoma of pyriform fossa.