Isolated Hypoglossal Nerve Palsy as an Early Symptom of a Granular Cell Tumor

Background: Hypoglossal nerve palsy (HNP) is rather common as a neurological disease. However, as an isolated nerve palsy it is an exceedingly rare phenomenon and points at local pathologies along the peripheral course of the nerve. In this communication we report a granular cell tumor (GCT) arising in the submandibular segment of the hypoglossal nerve. Case-Report: Spontaneous isolated HNP was recognized in a female patient. First line MR-imaging identified a clivus-chordoma. However, involvement of the hypoglossal nerve was highly unlikely according to MR-findings. Finally, ultrasonographic investigation revealed a small submandibular mass which, at histological examination, turned out to be a granular cell tumor arising within the hypoglossal nerve. Conclusions: This is the report of an extremely rare GCT originating within the 12th cranial nerve. The case illustrates that isolated motoric cranial nerve palsy may result from this rare tumor entity. This report also points out the diagnostic value of a simple ultrasonographic investigation to depict pathologic lesions of the submandibular space.

Single-stage total resection of giant dumbbell-shaped hypoglossal schwannoma: a case report

Extensive large dumbbell-shaped hypoglossal schwannoma is extremely rare, and total resection is nearly impossible. We present a case of a 61-year-old male with a giant-size hypoglossal schwannoma with moderate tongue atrophy. The tumor extended from the enlarged hypoglossal canal to the brainstem intradurally and the high cervical region extradurally. Through the extreme lateral infrajugular transcondylar (ELITE) skull base approach, the tumor was totally removed in a single-stage operation. Single-stage total resection is feasible by an experienced skull base team utilizing transcondylar skull base techniques and high cervical dissection.

Unilateral Hypoglossal Nerve Palsy Following the Use of the Laryngeal Mask Airway

Hypoglossal nerve injury is a rare complication of anesthetic airway management. We report a case of unilateral hypoglossal nerve injury following the use of the laryngeal mask airway (LMA). A 48-year-old man with no past medical history sustained a proximal humerus fracture. His pre-operative examination was normal except for a humerus fracture. Anesthesia was induced and a size-3 LMA was inserted successfully on first attempt without difficulty. The cuff was inflated with the recommended 20 ml of air until there was no leak and maintained at a pressure of 10-15 cm H20. The surgery was uneventful and the duration of anesthesia was two hours. Peri-operatively the patient was hemodynamically stable without episodes of hypotension. The recovery staff noted approximately three hours after the surgery that his tongue was deviated to the left. The patient complained of difficulty swallowing and slurred speech. He had normal sensation of his tongue, taste was unchanged, and the gag reflex was intact. No other cranial nerves were involved and no other neurological deficiency was found. The following day, there was significantly less dysarthria and slight improvement in tongue movement. Conservative management included speech therapy and regular assessment. He continued to improve and complete recovery took place within two weeks.

Occipital Condyle Fracture with Associated Hypoglossal Nerve Injury

Occipital condyle fracture (OCF) is a rare injury that was first described by Bell in 1817. In fact, there have been only 96 more reported cases of occipital condyle fractures from 1817 to 1994 of which only 58 survived. Occipital condyle fractures can sometimes go unnoticed or under-diagnosed as they are not always evident on plain radiographs of the cervical spine. Also, in rare cases OCFs can cause damage to the hypoglossal nerve which passes through the hypoglossal canal which is near the occipital condyle. The presence of specific symptoms and clinical signs should lead to the correct diagnosis. This paper describes a patient who was diagnosed with OCFs, but not hypoglossal nerve damage until 20 days following admission to hospital. We point out many factors that contributed to this delayed diagnosis, which ultimately caused severe discomfort to the patient.

[Isolated hypoglossal nerve paralysis: a case report]

Cranial nerve paralysis is an uncommon complication of radiotherapy for head and neck carcinomas because cranial nerves are relatively resistant to radiation. The incidence of this complication has been declared to be 1-5% in different studies. Unlike the other cranial nerves, isolated hypoglossal nerve paralysis in patients who have been treated with radiotherapy for nasopharyngeal carcinomas is a worrisome sign of recurrence. We report a 45-year-old male patient admitted to our clinics with complaints of difficulty in moving his tongue and dysphasia five years after combined radiotherapy and chemotherapy for nasopharyngeal carcinoma. Recurrence of the tumor was thought to be the cause of the isolated hypoglossal nerve paralysis at first, however late toxicity of radiotherapy was found to be the etiological factor after detailed examinations.

Hypoglossal schwannoma-successful reinnervation and functional recovery of the tongue following tumour removal and nerve grafting

OBJECTIVE

Hypoglossal nerve schwannomas are rare tumours that usually cause ipsilateral hypoglossal palsy. This report describes such lesions in two patients and suggests nerve grafting as part of the treatment regimen.

METHOD

Two patients with intra- and extra-dural hypoglossal schwannomas respectively were treated by direct surgery via a postero-lateral approach to the posterior fossa, hypoglossal canal and carotid sheath. Following tumour removal, sural nerve grafting was used to reconstruct the nerves. Unexpectedly, muscle bulk and motor function returned within 6 months in both patients.

CONCLUSION

Nerve grafting was highly successful in achieving functional recovery following surgery for hypoglossal nerve schwannomas.

Peripheral nerve injury induced expression of mRNA for serine protease inhibitor 3 in the rat facial and hypoglossal nuclei but not in the spinal cord

The current work has documented the expression of the mRNAs for serine protease inhibitor 3 (SPI-3) in the facial and hypoglossal nuclei following peripheral nerve transection by using the in situ hybridization method. The signals appeared 6 hour after nerve injury; they became stronger on day 1 of injury and persisted for 21 days. SPI-3 may be involved during early events of modulating the activities of serine proteases following nerve injury. Such activities may include synaptic stripping and re-organization and facilitation of glial cell reaction to nerve injury. In the later stages of nerve injury SPI-3 may enhance neuronal survival, growth of neurites and re-establishment of synaptic contacts in the facial and hypoglossal nuclei. Hypoglossal but not facial nerve transection caused the expression of mRNAs for SPI-3 in the pineal gland. The signals appeared 6 hours after nerve injury and persisted for 21 days. The significance of this observation is not known but it indicates that the pineal gland senses injury to some peripheral nerves including the hypoglossal nerve. The study has also showed that axotomy of the sciatic nerve did not give rise to the up-regulation of the mRNAs for SPI-3 in the spinal cord. There was no hybridization signals in the lumbar segments; an indication that SPI-3 may not form part of molecules that are released during sciatic nerve transaction by the neural and non-neural cells of the spinal cord. At the moment there are no antibodies for SPI-3 and therefore future studies are needed to verify the findings. It will be interesting also to study on the role of pineal gland during peripheral nerve injuries.

Hypoglossal schwannoma presenting as hemi-atrophy of the tongue

Schwannoma of the hypoglossal nerve is extremely rare. We report the clinical manifestations of a patient with Schwannoma of the hypoglossal nerve with hemi-atrophy of the tongue and numbness in the lip. Magnetic resonance image study of the brain showed a lobulated mass at the right posterior fossa with an extension to the right upper neck. Surgical intervention was performed with right occipital craniotomy and a partial resection of C1 and occipital condyle. Pathological studies confirmed a Schwannoma with hemorrhages and necrosis.

Melanocortin receptor 4 is induced in nerve‐injured motor and sensory neurons of mouse

We previously identified melanocortin receptor 4 (MC4R) in a search for genes associated with hypoglossal nerve regeneration. As melanocortins promote nerve regeneration after axonal injury, we investigated whether MC4R functions as a key receptor for peripheral nerve regeneration. In situ hybridization revealed that MC4R mRNA is induced in mouse hypoglossal motor neurons after axonal injury, whereas mRNAs for MC1R, MC2R, MC3R, and MC5R are not expressed either before or after nerve injury. This result was confirmed by RT-PCR. The level of MC4R mRNA expression increased significantly from day 3 after axotomy, reached a peak on day 5, and decreased to the control level on day 14. Similar induction of MC4R was observed in axotomized mouse dorsal root ganglia (DRGs). MC4R mRNA expression was induced exclusively among the MCR family in the L4-6 DRG after sciatic nerve injury. We further examined whether alpha-melanocortin stimulating hormone (alpha-MSH) promotes neurite elongation via MC4R. In mouse DRG neuron culture, alpha-MSH significantly promoted neurite outgrowth at a concentration of 10(-8) mol/L. This neurite-elongation effect was entirely inhibited by the addition of a selective MC4R blocker, JKC-363. Therefore, it is concluded that alpha-MSH could stimulate neurite elongation via MC4R in DRG neurons. The present results suggest that induction of MC4R is crucial for motor and sensory neurons to regenerate after axonal injury.

"Triple cross" of the hypoglossal nerve and its microsurgical impact to entrapment disorders

OBJECTIVE

Cadaveric dissections were performed to review the intracranial and extracranial course of the hypoglossal nerve. The neurological significance of a newly defined "triple cross" of the hypoglossal nerve is discussed.

MATERIALS AND METHODS

10 cadaveric heads (left and right; 20 sides) were dissected using microsurgical techniques.

RESULTS

In the cisternal segment of hypoglossal nerve, the diameter of the rostral trunk amounted to 155-680 microm (mean 435 microm), and the caudal trunk to 210-820 microm (mean 482 microm). The roots formed three trunks in 20% of the hypoglossal nerves and two trunks in the rest. As a first cross, the anterior medullary segment of the vertebral artery crossed the hypoglossal nerve roots in 14 of 20 sides (70%). As a rare variation, the vertebral artery extended medial to the nerve (25%) or between its roots (5%). The second cross was found between the descendens hypoglossus and the occipital artery (75%), sternocleidomastoid artery and vein complex (15%) and external carotid artery (10%). The third cross was shown in the submandibular triangle between the lingual hypoglossus and its drainage vein; vena committans nervus hypoglossus.

CONCLUSION

Throughout its way, the hypoglossal nerve passes over vascular structures in three crossing points which may serve as a probable cause of hypoglossal nerve entrapment disorders.

The midline suboccipital subtonsillar approach to the hypoglossal canal: surgical anatomy and clinical application

Primary lesions of the hypoglossal canal, such as hypoglossal schwannomas, are rare. No consensus exists with regard to the surgical approach of choice for treatment of these lesions. Usually, lateral transcondylar approaches have been used. The authors describe the surgical anatomy of the midline subtonsillar approach to the hypoglossal canal. This approach includes a midline suboccipital craniotomy, dorsal opening of the foramen magnum and elevation of ipsilateral cerebellar tonsil to expose the hypoglossal nerve and its canal. The midline subtonsillar approach permits a straight primary intradural view to the hypoglossal canal. There is no necessity of condylar resections. The surgical anatomy of the subtonsillar approach is described and illustrated by an example of a case.

[Neurilemmoma of the head and neck--report of 3 cases]

BACKGROUND

Neurilemmoma are benign tumors of the nerve-sheath, also known as schwannoma. Beside intracranial manifestation, neurilemmoma are found at other peripheral nerves of the head and neck.

CASE REPORT

We present three cases of patients with seldom manifestation of neurilemmoma of the supraglottis, the retropharyngeal space and a neurilemmoma of the hypoglossal nerve. The histological examination showed two types of Antoni-A-neurilemmoma, whereas one tumor was found with mixed type A and B-neurilemmoma.

CONCLUSION

Although extracranial neurilemmoma of retropharygeal space, neck or supraglottic larynx are rare tumors, neurilemmoma should be involved in differential diagnosis of tumors in these areas. The therapy of choice consists of complete surgical removal and histological examination.

Das „ancient schwannoma“

"Ancient schwannomas" of the mouth floor are rare, benign neoplasms derived from the nerve sheath of peripheral nerves. They show many degenerative changes such as necrosis and vascular thrombosis. Ancient schwannomas show histopathological features, such as degenerative changes and atypical nuclei, and may easily be confused with malignant neoplasms. B-scan sonography for the mouth floor and MRT imaging may be helpful in differential diagnosis. Here, we report on a patient with ancient schwannoma of the floor of the mouth.

Endoscope-assisted microsurgical resection of an intraneural ganglion cyst of the hypoglossal nerve

✓ An unusual case of an intraneural ganglion cyst of the hypoglossal nerve is presented. Only one case of this rare clinical entity has been reported previously. A 51-year-old woman presented with a 6-month history of left-sided hypoglossal nerve palsy. Magnetic resonance imaging revealed a cystic lesion related to the hypoglossal canal. There was no enhancement of the lesion after administration of Gd. A high-resolution computerized tomography scan of the skull base demonstrated an enlargement of the hypoglossal canal.

To access the lesion, a far-lateral endoscope-assisted microsurgical approach was used. An intraneural ganglion lesion invading the hypoglossal nerve was found and resected. A histopathological examination confirmed that the lesion was an intraneural ganglion cyst. The occurrence of an intraneural ganglion cyst at the hypoglossal nerve is very rare. This case exemplifies an atypical location of a synovial cyst with cranial nerve involvement.

[Schwannoma of the hypoglossal nerve presenting as a syndrome of Collet-Sicard]

Collet-Sicard is a rare syndrome that consists of the palsy of all the lower four cranial nerves. We describe this entity in relation with a schwannoma of the hypoglossal nerve. A 45 year-old-patient was admitted to the hospital referring hoarseness and difficulty in swallowing for two weeks. On neurological examination, the patient exhibited palsy of the ninth, tenth, eleventh and twelfth nerves. This is a syndrome of Collet-Sicard. The cranial MRI revealed a small intracranial and extracranial tumor adjacent to the hypoglossal foramen. The tumor involved the jugular foramen and was moderately enhanced with gadolinium The patient underwent surgical removal. The pathologic examination of the surgical specimen confirmed the diagnosis of a schwannoma of the hypoglossal nerve. We have carried out a research of the Collet-Sicard syndrome and of its aetiology. Although schwannoma the hypoglossal nerve is a rare disorder we consider that this entity should be included in the differential diagnosis of the Collet-Sicard syndrome.

Navigated dorsolateral suboccipital transcondylar (NADOSTA) approach for treatment of hypoglossal schwannoma

Hypoglossal schwannoma is a rare skull base neoplasm, which lies in the midst of extremely complex anatomical structures. We report a 39-year-old man who presented with a history of right glossal hemiatrophy, dysesthesia and weakness of the left extremities. These symptoms were caused by a unilateral hypoglossal schwannoma located at the cranial base. This lesion was exposed through a dorsolateral suboccipital transcondylar approach, which was navigated with the frameless stereotaxy (NADOSTA). We also describe the epidemiology, symptomatology and the diagnosis of hypoglossal schwannoma as well as literature review of the operative approach. By introducing this minimally invasive dorsal surgical approach with neuronavigation in treating hypoglossal schwannoma, we believe that safe exposure and complete tumor resection can be achieved with minimal rate of morbidity.

[Acute palsy of twelfth cranial nerve]

The hypoglossal nerve or Twelfth-nerve palsy is a rare damage with different causes: tumors or metastases in skull base, cervicals tumors, schwannoma, dissection or aneurysm carotid arteries, stroke, trauma, idiopathic cause, radiation, infections (mononucleosis) or multiple cranial neuropathy. Tumors were responsible for nearly half of the cases in different studies. We studied a female with hypoglossal nerve acute palsy. We made a differential diagnostic with others causes and a review of the literature.

Critical role for DP5/Harakiri, a Bcl-2 homology domain 3-only Bcl-2 family member, in axotomy-induced neuronal cell death

The survival of neurons is maintained primarily by neurotrophic factors that suppress the apoptotic program. Axotomy or removal of peripheral targets causes neuronal cell death, but the mechanisms involved in the induction of this type of cell death remain poorly understood. Here, we show that DP5/Harakiri, a Bcl-2 homology domain 3-only member of the Bcl-2 family, is induced in motoneurons after transection of the hypoglossal nerve in mice and in sympathetic neurons after nerve growth factor (NGF) withdrawal. To assess the role of DP5 in neuronal cell death, mutant mice deficient in DP5 were generated by gene targeting. DP5-/- mice were viable and exhibited normal postnatal development. Notably, motoneurons from DP5-/- mice were highly protected from cell death induced by resection of the hypoglossal nerve compared with motoneurons from DP5+/+ littermate mice. In addition, deficiency of DP5 in superior cervical ganglia (SCG) neurons resulted in delayed neuronal cell death triggered by NGF withdrawal. Analysis of SCG neurons from DP5-/- mice revealed increased preservation of mitochondrial membrane potential and reduced activation of caspase-3 compared with neurons from wild-type mice. These results indicate that DP5 plays an important role in neuronal cell death induced by axotomy and NGF deprivation through the regulation of mitochondrial function and caspase-3 activation.

Bilateral hypoglossal schwannoma: a radiologic diagnosis

A 53-year-old woman presented with a complaint of a sore throat. Examination showed a left-sided atrophy of the tongue. Upon protrusion, the tongue deviated to the left, suggestive of a unilateral hypoglossal nerve palsy. Computed tomography revealed enlarged hypoglossal canals. Magnetic resonance imaging (MRI) demonstrated bilateral hypoglossal canal masses, with enhancement following gadolinium administration. Magnetic resonance angiography and MRI with fat suppression revealed nonvascular masses in both hypoglossal canals. Radiological diagnosis of bilateral hypoglossal nerve schwannoma was made and the patient was scheduled for MRI monitoring with six-month intervals. The size of the masses and the clinical manifestations remained unchanged during a two-year follow-up period.

[Isolated unilateral hypoglossal nerve paralysis: a report of two cases]

Two cases of unilateral isolated hypoglossal nerve paralysis are presented. One patient (aged 56 years, male) had a history of intubation during open cardiac surgery. Spontaneous clinical improvement was observed about 3.5 months after the onset of paralysis. In the other patient (aged 42 years, female), the onset of paralysis dated back 23 years before. Since no etiologic cause could be determined to be associated with hypoglossal nerve paralysis either at the time of onset or on final examinations, the case was thought to be idiopathic. No clinical improvement was observed during a six-month follow-up period.

Isolated unilateral hypoglossal nerve paralysis caused by an atlanto-occipital joint synovial cyst

An isolated unilateral hypoglossal nerve lesion is an uncommon cranial nerve palsy. We report a case of isolated hypoglossal nerve paralysis caused by an intra-dural synovial cyst. To our knowledge, this is the first reported case of a twelfth nerve paralysis caused by a synovial cyst. The anatomy of the hypoglossal nerve, its blood supply and the relationship of the nerve to the atlanto-occipital joint are reviewed, along with the common causes of isolated hypoglossal nerve paralysis.

Solitary fibrous tumor of the hypoglossal nerve

SUMMARY

We report a case of solitary fibrous tumor (SFT) causing isolated hypoglossal nerve palsy. The neuroimaging appearance of the tumor was indistinguishable from that of schwannoma or meningioma. Immunohistochemical tests demonstrated strong reactivity for CD34 but an absence of staining for S100 and epithelial membrane antigen; this profile is indicative of an SFT. SFTs are mesenchymal tumors that can affect the dura-covered segments of cranial nerves. They may be considered in the differential diagnosis of an isolated cranial nerve palsy.

Fibrous dysplasia of the clivus

OBJECTIVE

Fibrous dysplasia is a developmental skeletal disorder that may lead to distortion, expansion, and weakening of the bone. Craniofacial involvement by this entity is well recognized and is known to cause neurovascular impingement and cosmetic deformity; fibrous dysplasia of the clivus, however, is unrecognized and seldom reported. Differentiating this entity from more aggressive disease processes affecting the clivus is central for the proper management of lesions in this area. We have studied fibrous dysplasia of the clivus with the goal of depicting its manifestations, outlining its management, and heightening awareness of this disease entity.

METHODS

We retrospectively reviewed our database and identified patients with the diagnosis of fibrous dysplasia of the clivus. The demographic data, the clinical and radiological findings, and the management of these patients were reviewed.

RESULTS

Eight patients who had experienced fibrous dysplasia of the clivus were identified. They either were asymptomatic (four patients) or presented with headache (four patients). Of the patients who presented with headache, one also had XIIth cranial nerve paralysis and another had dysphagia. The radiological findings for this entity were consistent, with typical findings of hypointensity on T1- and T2-weighted magnetic resonance imaging studies and ground-glass appearance on computed tomographic scans. Four of the patients in our series had pathological confirmation. Treatment was determined by the patient's symptoms.

CONCLUSION

Fibrous dysplasia should be considered in the differential diagnosis of lesions affecting the clivus. Its clinical and radiological presentations permit the establishment of the diagnosis. Its management is usually conservative, unless the patient presents with nerve compression or extensive symptomatic involvement of the condyle.

Rare localization of paraganglioma in head and neck

In this paper, we describe the clinical course of a 61-year-old female patient with paraganglioma in the head and neck region. Computed tomographic scan (CT), magnetic resonance imaging (MRI), ultrasound scan (US) and arteriogram findings initially led us to suspect that this tumor originated in the vagal nerve. In particular, a color Doppler US enabled an easy diagnosis of hypervascular tumor. We removed this surgically, but the tumor was easy to peel from the vagal nerve and carotid bifurcation. The distal side of the tumor was under the digastric muscle and running into the hypoglossal nerve. The intraoperative findings were highly suggestive of localization at the hypoglossal nerve, although Xth and XIIth cranial nerve palsies have remained.

Isolated unilateral hypoglossal nerve palsy after minor head trauma

Isolated unilateral hypoglossal nerve palsy after fracture of the occipital condyle is rare. It usually occurs after major trauma, such as high-speed deceleration injuries following road traffic accidents. We describe a case that resulted from minor trauma. An underlying skull base malformation may have been a predisposing factor.

Cranial nerve XII: the hypoglossal nerve

The hypoglossal nerve, cranial nerve XII, is the motor supply of the tongue. An understanding of the intracranial and extracranial components is fundamental in the evaluation of hypoglossal pathology. The following discussion of the evaluation of the hypoglossal nerve will involve the embryology, anatomy, clinical basis, and imaging techniques with pathologic correlations.

Hypoglossal schwannoma in the submandibular space

Most schwannomas of the hypoglossal nerve originate from the intracranial portion, but they may extend extracranially. Solitary and extracranial schwannomas are extremely rare. We report a case of submandibular hypoglossal schwannoma along with its clinical course and management.

[How I treat ... facial paralysis by hypoglosso-facial anastomosis]

Thirteen patients underwent a hypoglosso- or a spino-facial nerve anastomosis between 1990 and 1996. Facial palsy was the result of surgery in 12 cases and of radiosurgery in 1 case. The mean interval between facial palsy and anastomosis was 12 months. Facial nerve function is determined on the basis of clinical examination according to the classification of House-Brackmann and our own evaluation. According to House, 10 patients are classified grade III and 3 grade IV. Our evaluation defines in 10 grade III, 7 good results and 3 fair results. As far as the good results are concerned, the mean interval between palsy and anastomosis is short (< 3 months). The permanent eating and swallowing dysfunctions are consecutive to multiple cranial nerve deficits. The post-paralysis hemifacial spasm is facilitated by prolongated electric stimulations.

Dejerine's syndrome or Spiller's syndrome?

We report the difference existing between two clinical syndromes: Spiller's syndrome is caused by a complete involvement of the medial hemimedulla, while Déjérine's syndrome is determined by lesions restricted to the anterior portion of the medial hemimedulla and is characterized by hypoglossal nerve palsy and contralateral hemiparesis.

[Arachnoid cyst with consecutive brain stem atrophy, hypoglossal nerve paresis and tongue atrophy]

We report the pathological anatomy of a patient aged 77 years at the time of death, who suffered from an arachnoid cyst situated near the right lower olive nucleus. This led to palsy of the hypoglossal nerve and partial gliosis of the brainstem with consecutive hemiatrophy of the tongue. This lesion did not seem to have any further effects onto clinical presentation. The patient died of a fulminant lung embolism and also presented an adenocarcinoma of the lung.