Magnetic resonance imaging features of bilateral multiloculated extraneural ganglion cysts of the occipito-atlanto-axial joint causing hypoglossal nerve paralysis in a dog.

A 14-year-old spayed female Miniature Pinscher presented with tongue curling, dysphagia, hypersalivation, and sublingual gland swelling. Comprehensive evaluation, including neurologic and musculoskeletal examinations, blood work, and urinalysis, revealed no abnormalities other than tongue-related signs. Magnetic resonance imaging (MRI) revealed a multilobed cystic structure in the occipito-atlanto-axial joint, compressing the right hypoglossal canal. The lesion appeared cerebrospinal fluid (CSF)-like on T1-weighted and T2-weighted images, and hyperintense compared with CSF on fluid-attenuated inversion recovery T2-weighted images. The scans suggested mucinous content with enhanced peripheral areas on contrast-enhanced images. Surgical removal and drainage of this cyst were performed, and clinical signs improved markedly. The dorsal cyst was tentatively diagnosed as a ganglion cyst based on histopathologic and imaging findings. Ganglion cysts should be considered in the differential diagnosis for dogs with similar MRI findings and neurologic signs.

Isolated unilateral hypoglossal nerve palsy from suppurative retropharyngeal lymphadenitis in an infant.

Retropharyngeal infections (RPIs) are uncommon in young infants and are difficult to diagnose due to their non-classical presentation. RPI can occasionally be complicated with multiple cranial nerve palsies but rarely in isolation. Isolated hypoglossal nerve palsy (HNP) due to RPI has been described in the literature but mostly in older children and adults. Assessment for hypoglossal nerve function is challenging in a young infant because the conventional signs of hypoglossal nerve dysfunction are difficult to elicit in this age group. Early recognition and treatment of RPI are associated with good HNP recovery. We present a case of a young infant with tongue deviation and difficulty with feeding attributed to an isolated HNP caused by suppurative retropharyngeal lymphadenitis. The infant underwent incision and drainage with complete recovery of the tongue function after 8 weeks.

An unexpected complication of hypoglossal schwannoma surgery: Cerebrospinal fluid leakage-A case report and literature review.

BACKGROUND: Extracranial hypoglossal schwannoma is a rare tumor primarily treated with surgical excision. This article aims to highlight the potential for unexpected complications intraoperatively, such as cerebrospinal fluid leakage from skullbase to neck. METHODS: A previously healthy 23-year-old male presented with tongue numbness. Magnetic resonance imaging revealed a 17 × 20 mm nodular lesion adjacent to the cervical segment of the internal carotid artery. Surgical excision was scheduled due to suspicion of a neurogenic tumor. RESULTS: Intraoperatively, despite careful handling, cerebrospinal fluid leakage was observed. Manipulation of the mass caused detachment of proximal nerve fibers, potentially indicating avulsion of the hypoglossal nerve from the brainstem or nearby. Clear fluid leakage from the skull base was also noted. CONCLUSION: Thorough preoperative evaluation and patient education regarding potential complications are crucial. This article presents an unexpected complication encountered during surgical excision of extracranial hypoglossal schwannoma, emphasizing the need for awareness and preparedness in such cases.

Tongue electrical impedance myography correlates with functional, neurophysiologic, and clinical outcome measures in long-term oropharyngeal cancer survivors with and without hypoglossal neuropathy: An exploratory study.

BACKGROUND: This pilot study analyzed correlations between tongue electrical impedance myography (EIM), standard tongue electromyography (EMG), and tongue functional measures in N = 4 long-term oropharyngeal cancer (OPC) survivors. METHODS: Patients were screened for a supportive care trial (NCT04151082). Hypoglossal nerve function was evaluated with genioglossus needle EMG, functional measures with the Iowa oral performance instrument (IOPI), and multi-frequency tissue composition with tongue EIM. RESULTS: Tongue EIM conductivity was higher for patients with EMG-confirmed cranial nerve XII neuropathy than those without (p = 0.005) and in patients with mild versus normal EMG reinnervation ratings (16 kHz EIM: p = 0.051). Tongue EIM correlated with IOPI strength measurements (e.g., anterior maximum isometric lingual strength: r2 = 0.62, p = 0.020). CONCLUSIONS: Tongue EIM measures related to tongue strength and the presence of XII neuropathy. Noninvasive tongue EIM may be a convenient adjunctive biomarker to assess tongue health in OPC survivors.

An interesting case of crossed syndrome: ipsilateral facial paralysis with contralateral glossoplegia.

BACKGROUND: Stroke is rarely accompanied with peripheral facial paralysis and supranuclear palsy of the hypoglossal nerve. Both sides of the motor cortex innervate the hypoglossal nucleus; therefore, unilateral lesions of the upper motor neurons rarely result in contralateral lingual paresis. We report a rare case of crossed syndrome with associated hyperacute peripheral hemifacial paralysis and contralateral lingual paresis after a lower pontine tegmentum ischemic stroke. CASE PRESENTATION: A 73-year-old man presented with symptoms of hyperacute peripheral hemifacial paralysis. Upon protrusion, the patient's tongue deviated to the contralateral side, without fasciculation or atrophy. Brain imaging showed focal ischemic stroke in the pontine tegmentum. However, lingual hemiparesis and multimodal neuroimaging findings differed. CONCLUSIONS: We suggest that cortico-hypoglossal fibers pass through the dorsal pontine. This case of crossed syndrome is a rare report of a lower pontine tegmentum ischemic stroke resembling an upper motor neuron lesion of the contralateral hypoglossal nerve.

Hypoglossal nerve palsy in a patient with internal carotic dissection.

This is a case report of a 38-year-old, previously healthy man who was initially seen at an otorhinolaryngological department due to "swelling" of his tongue. Further history revealed four days of severe, non-specific headache and lisping. Two weeks prior to hospital admission he had seen a chiropractor due to neck pain. On examination at the hospital there was isolated left hypoglossal nerve palsy. He was urgently referred to a department of neurology. Magnetic resonance angiography showed internal carotid artery dissection. Aspirin and clopidogrel were commenced. At the three months follow-up examination he had recovered completely symptom wise and a renewed magnetic resonance imaging was normal.

The Hypoglossal Nerve.

The hypoglossal nerve is the 12th cranial nerve, exiting the brainstem in the preolivary sulcus, passing through the premedullary cistern, and exiting the skull through the hypoglossal canal. This is a purely motor nerve, responsible for the innervation of all the intrinsic tongue muscles (superior longitudinal muscle, inferior longitudinal muscle, transverse muscle, and vertical muscle), 3 extrinsic tongue muscles (styloglossus, hyoglossus, and genioglossus), and the geniohyoid muscle. Magnetic resonance imaging (MRI) is the best imaging exam to evaluate patients with clinical signs of hypoglossal nerve palsy, and computed tomography may have a complementary role in the evaluation of bone lesions affecting the hypoglossal canal. A heavily T2-weighted sequence, such as fast imaging employing steady-state acquisition (FIESTA) or constructive interference steady state (CISS) is important to evaluate this nerve on MRI. There are multiple causes of hypoglossal nerve palsy, being neoplasia the most common cause, but vascular lesions, inflammatory diseases, infections, and trauma can also affect this nerve. The purpose of this article is to review the hypoglossal nerve anatomy, discuss the best imaging techniques to evaluate this nerve and demonstrate the imaging aspect of the main diseases that affect it.

Bilateral Tapia's syndrome secondary to cervical spine injury: a case report and literature review.

A 24-year-old man presented with bilateral Tapia's syndrome (TS) after a traumatic cervical spine injury, manifested by apraxia of the hypoglossal and recurrent laryngeal nerves. The initial presentation was a profound inability to maintain upper respiratory airway patency due to bilateral vocal cord paralysis, accompanied by impairment of swallowing and loss of speech. The diagnosis was based on clinical grounds and verified by endoscopic laryngoscopy. A C7 corpectomy was performed for stabilizing the cervical spine, while conservative treatment with steroids was reserved for the TS. Over the following six months, there was complete resolution of the symptoms.

Important aspect of hypoglossal nerve injury following gunshot wound; Can the clivus has a role? A case report.

Cranial nerve palsies after gunshot injury are not uncommon. We report the mechanism of isolated hypoglossal nerve paralysis caused by a gunshot. We report a 74 years old patient in whom a bullet entered through the right nostril and then ended up right occipital condyle. The only neurologic deficit was tongue deviation which resolved in one week. The bullet was not removed. The effect of clival slope may have an importance in this type of injury.

Yin-Yang tongue sign: An imaging clue of lesions involving the skull base segment in the hypoglossal pathway.

OBJECTIVE: To investigate the diagnostic value of the Yin-Yang tongue sign in patients with tongue deviation. METHODS: According to the presence of the Yin-Yang tongue sign on CT/MR, 107 patients with tongue deviation were divided into a positive group and a negative group. The involvement categories of the hypoglossal canal (HC) in the positive group were evaluated and classified as HC dilation and HC erosion. The correlations between HC involvement categories and the presence of the sign were analysed. RESULTS: There were 55 cases (55/107, 51.4%) in the positive group and 52 cases (52/107, 48.6%) in the negative group. Hypoglossal nerve (HN) involvement mainly occurred in the skull base (61.8%), skull base and carotid space (10.9%), and carotid space segment (12.7%). Neurogenic (50.9%), squamous cell carcinoma (14.5%), and metastases (12.7%) were the predominant aetiologies. The sensitivity, specificity, and accuracy of this sign for suggesting skull base lesions around HC were 72.4%, 80.8%, and 76.6%, respectively. In the positive group, HC dilation was seen in 21 patients (21/55, 38.2%) and 21 cases were all benign. HC erosion were noted in 19 patients (19/55, 34.5%), of whom 12 cases were malignant. CONCLUSION: The Yin-Yang tongue sign is formed by unilateral tongue atrophy and fat infiltration caused by lesions in the HN pathway, especially compressive or invasive lesions involving the skull base segment.

Tapia's syndrome in a patient with COVID-19.

A 42-year-old man developed bilateral Tapia's syndrome (recurrent laryngeal and hypoglossal nerves paralysis) following prolonged ventilation for COVID-19 pneumonia. Examination showed global tongue atrophy and bilateral asymmetric vocal cord palsy. He improved rapidly without specific treatment, suggesting that neuropraxia was the likely mechanism of injury. Tapia's syndrome has been reported disproportionately more often in association with COVID-19, possibly from injury to hypoglossal and vagal nerves during ventilation in the prone position.