Imaging and Surgical Findings in Patients with Hemi-Laryngopharyngeal Spasm and the Potential Role of MRI in the Diagnostic Work-Up

Microvascular Decompression for Concurrent Trigeminal Neuralgia and Hemi-Laryngopharyngeal Spasm: A Case Report

BACKGROUND AND IMPORTANCE

Hemi-laryngopharyngeal spasm (HeLPS) may result from vascular compression of the vagus nerve and can be treated using microvascular decompression. We describe the clinical characteristics and surgical treatment in a case of concurrent trigeminal neuralgia (TN) and HeLPS.

CLINICAL PRESENTATION

A 44-year-old man presented with a 12-month history of right TN and 8-month history of intermittent episodes of repeated throat contractions associated with a very distressing choking sensation. Preoperative 3-dimensional fusion imaging demonstrated compression of the trigeminal nerve by the superior cerebellar artery and petrosal vein and compression of the vagus nerve by the posterior inferior cerebellar artery and one of its branches. Microvascular decompression was performed by a right standard retrosigmoid approach with enlarged craniotomy. Initially, the compression of the trigeminal nerve was identified by visual inspection. All the offending vessels were wrapped in Teflon felt, transposed away from the trigeminal nerve, and adhered to the tentorial membrane and petrous bone using fibrin glue. Furthermore, observation of the caudal rootlets of the vagus nerve revealed that the posterior inferior cerebellar artery and its branch compressed the ventral side of the nerve. These vessels were displaced antero-caudally with Teflon felt and fibrin glue; no other vessels were found around the trigeminal and vagus nerves. Postoperatively, the patient had immediate and complete resolution of symptoms of TN and HeLPS without recurrence at the 18-month follow-up.

CONCLUSION

HeLPS may occur with TN, and neurosurgeons should identify the symptoms suspicious of this disease preoperatively.

Supraglottic Botulinum Toxin Improves Symptoms in Patients with Laryngeal Sensory Dysfunction Manifesting as Abnormal Throat Sensation and/or Chronic Refractory Cough

Laryngeal sensory dysfunction (LSD) encompasses disorders of the vagal sensory pathways. Common manifestations include chronic refractory cough (CRC) and abnormal throat sensation (ATS). This study examined clinical characteristics and treatment outcomes of LSD using a novel approach of laryngeal supraglottic Onabotulinum toxin Type A injection (BTX). This was a retrospective review of clinical data and treatment outcomes of supraglottic BTX in patients with LSD. Between November 2019 and May 2021, 14 patients underwent 25 injection cycles of supraglottic BTX for treatment of symptoms related to LSD, including ATS and CRC. Primary outcome measures included the Newcastle Laryngeal Hypersensitivity Questionnaire (LHQ), Cough Severity Index (CSI), Reflux Symptom Index (RSI), and Voice Handicap Index-10 (VHI-10) at baseline and within three months of treatment. Pre- and post-treatment data were compared using a linear mixed model. After supraglottic BTX, LHQ scores improved by 2.6. RSI and CSI improved by 8.0 and 5.0, respectively. VHI-10 did not change as a result of treatment. Short-term response to SLN block was significantly associated with longer term response to BTX treatment. These findings suggest that LSD presents clinically as ATS and CRC along with other upper airway symptoms. Supraglottic BTX injection is a safe and effective technique in the treatment of symptoms of LSD.

Hemi-laryngopharyngeal Spasm (HeLPS): Defining a New Clinical Entity

OBJECTIVE

Hemi-laryngopharyngeal spasm (HeLPS) has recently been described in the neurosurgical literature as a cause of intermittent laryngopharyngeal spasm and cough due to vascular compression of the vagus nerve at the cerebellopontine angle. We present the diagnostic criteria for this syndrome.

METHODS

A retrospective chart review of six patients with HeLPS and three patients misdiagnosed with this condition are presented. All patients were diagnosed and treated at a tertiary care academic centre from July 2013 to July 2017.

RESULTS

Patients with HeLPS had five defining characteristics: 1) All patients had symptoms of episodic laryngopharyngeal spasm and coughing. Patients were asymptomatic between episodes and were refractory to speech therapy and reflux management. 2) Laryngoscopy showed hyperactive twitching of the ipsilateral vocal fold in two of the six patients. No other inter-episodic abnormalities were seen. 3) Botulinum toxin A injections into the thyroarytenoid muscle on the affected ipsilateral side reduced laryngopharyngeal spasms. Botulinum toxin injection in the contralateral thyroarytenoid muscle did not improve laryngopharyngeal spasm. 4) Magnetic resonance imaging revealed ipsilateral neurovascular compression of the vagus nerve rootlets by the posterior inferior cerebellar artery. 5) Microvascular decompression (MVD) surgery of the ipsilateral vagus nerve resolved all symptoms (follow-up 2-4 years).

CONCLUSION

The diagnostic criteria for hemi-laryngopharyngeal spasm (HeLPS) are proposed. Otolaryngology recognition of this new clinical entity may lead to a surgical cure and avoid the unnecessary therapies associated with misdiagnosis.

LEVEL OF EVIDENCE

4.

Vagus Associated Neurogenic Cough Occurring Due to Unilateral Vascular Encroachment of Its Root: A Case Report and Proof of Concept of VANCOUVER Syndrome

OBJECTIVES

A patient is presented with neurogenic cough due to a unilateral vascular compression of a vagus nerve rootlet at the brainstem with complete resolution of cough following microvascular decompression of that nerve. This etiology of a neurogenic cough has not been previously reported to our knowledge. The proportion of patients with neurogenic cough refractory to all current therapies and suffering with this treatable condition remains to be defined. We introduce the concept of Vagus Associated Neurogenic Cough Occurring due to Unilateral Vascular Encroachment of its Root (VANCOUVER syndrome) and present the salient features of this condition.

METHODS

A case review is presented with details of the patient's history, examination, imaging, laryngoscopy, intraoperative findings, and long-term clinical outcome.

RESULTS

A 60-year-old man presented with a 15-year history of non-productive cough refractory to antibiotics, and anti-reflux medications. Investigations by an allergist, a cardiologist, a gastroenterologist, two pulmonologists, and an otolaryngologist were negative. MRI demonstrated a vascular compression of his left vagus nerve and microvascular decompression of that nerve resolved his symptoms. There were no surgical complications and the patient remains asymptomatic at 1 year.

CONCLUSIONS

Neurogenic cough has been likened to a vagus nerve neuropathy in a similar way that trigeminal neuralgia is a trigeminal nerve neuropathy. Both cause intermittent sensory phenomena in their distribution and can be ameliorated with neuropathic medications. We demonstrate that neurogenic cough, like trigeminal neuralgia, may be caused by a vascular compression of its nerve root. A proposed mechanism of this type of neurogenic cough is presented along with a potential diagnostic paradigm for these patients.