Correlation between enhanced MRI and surgical findings in herpes zoster oticus

Contrast-Enhanced MRI Is Useful for Prognostic Prediction on Idiopathic Bilateral Simultaneous Facial Nerve Palsy: A Case Report and Literature Review

Idiopathic bilateral facial nerve palsy is a rare condition and presents a diagnostic and prognostic challenge. Specifically, when bilateral nerves are damaged, it is difficult to predict the prognosis. We showcase the usefulness of contrast-enhanced magnetic resonance imaging (MRI) by providing information about localization and severity of degeneration of facial nerve. A 70-year-old Japanese man presented with bilateral simultaneous facial nerve palsy of House-Brackmann Grade VI on both sides. Contrast-enhanced MRI revealed bilateral intensity enhancement of intratemporal facial nerves. The signal intensity was higher on the left side than on the right side. Facial nerve decompression was performed on the left side. The left facial nerve palsy was finally improved eight months after the onset, while the right side was improved just under two months after the onset. Contrast-enhanced MRI for facial nerve palsy can provide valuable information for the evaluation of damaged facial nerves. In our patient's case, it was useful as a prognostic predictor of bilateral facial nerve palsy.

Ramsay Hunt syndrome with multiple cranial neuropathy: a literature review

BACKGROUND

Ramsay Hunt Syndrome (RHS) is a neurotological disorder involving the reactivation of the varicella-zoster virus (VZV) in the geniculate ganglion of the facial nerve (Sweeney and Gilden in J Neurol Neurosurg Psychiatry 71:149-154, 2001). The characteristic presentation involves ipsilateral lower motor neuron type facial paresis, auricular pain with or without hearing impairment, and vesicular lesions of the external auditory canal and outer ear. Involvement of the facial and vestibulocochlear nerve is typical in RHS, whilst multiple cranial neuropathies are rare and associated with poorer prognosis and systemic complications (Arya et al. in Am J Case Rep 19:68-71, 2017; Shinha and Krishna in IDCases 2:47-48, 2015; Shim et al. in Acta Otolaryngol 131:210-215, 2011; Coleman et al. in J Voice 26:e27-e28, 2012; Morelli et al. in Neurol Sci 29:497-498, 2008;). Likely mechanisms involved in the pathogenesis of cranial polyneuropathy include direct peri-neural and trans-axonal spread of viral inflammation between contiguous cranial nerves and haematogenous dissemination between nerves with shared blood supply. Impairments in speech, swallowing, hearing, and oculo-protection can contribute to morbidity and requires a multidisciplinary approach to patient care.

METHODS

We present a rare case of RHS with multiple cranial neuropathies followed by a comprehensive review of current literature with regard to the pathophysiology, diagnostic workup, and the management strategies employed in these patients.

CONCLUSION

RHSs with multiple cranial neuropathies are important to recognise as they are associated with significant morbidity and poor prognosis. A multidisciplinary approach to patient management is required to address the several complications that can arise from cranial nerve deficits, especially in regard to speech and swallow.

Contrast-enhanced magnetic resonance imaging of facial nerve swelling in patients with severe Ramsay Hunt syndrome

OBJECTIVE

In Ramsay Hunt syndrome, contrast enhancement of magnetic resonance (MR) imaging seen in the affected facial nerve in the majority of cases, but its clinical significance has not been well investigated to date. The aim of this study was to elucidate the clinical significance of this imaging sign by quantitively investigating the correlation between the signal increase and swelling of the facial nerve. We also investigated the temporal change in this sign and its correlation with recovery.

METHODS

We retrospectively evaluated swelling of the facial nerve in 16 patients with severe Ramsay Hunt syndrome who underwent both contrast-enhanced magnetic resonance imaging and facial nerve decompression surgery via a transmastoid approach alone or in combination with a middle cranial approach. All the patients had a Yanagihara score of ≤8 points and facial nerve degeneration of ≥90% confirmed by either a nerve excitability test or electroneurography. Swelling of the facial nerve was evaluated intraoperatively using a 4-point grading system.

RESULTS

A significant correlation was observed between contrast enhancement on T1-weighted images and facial nerve swelling in the labyrinthine segment, geniculate ganglion, and pyramidal segment (P = 0.030, P = 0.018, and P = 0.037, respectively). Furthermore, the contrast enhancement increased significantly as more time elapsed after the onset of facial palsy (mean ± standard error, 14.7 ± 2.3 days, range, 5-42 days) in the geniculate ganglion and pyramidal segment (correlation coefficient, 0.546 and 0.689, P = 0.022 and P = 0.002, respectively). Patients with good recovery (Yanagihara score of ≥36) showed significantly lower contrast enhancement in the tympanic and mastoid segments (P = 0.021 and 0.020, respectively) than those who with poor recovery.

CONCLUSION

In particular segments of the facial nerve, contrast enhancement on T1-weighted image correlated with facial nerve swelling and recovery. These observations underscore the clinical significance of contrast enhancement on T1-weighted images in patients with Ramsay Hunt syndrome.

Delayed transmastoid facial nerve decompression surgery in patients with Ramsay-Hunt syndrome presenting with neurophysiologically complete paralysis

OBJECTIVES

To determine the efficacy of delayed transmastoid facial nerve decompression in patients with Ramsay Hunt Syndrome (RHS) presenting with complete facial paralysis.

METHODS

Twenty-five RHS patients with complete facial nerve paralysis presenting electroneuronographic (ENoG) degeneration ≥90% underwent transmastoid facial nerve decompression more than 3 weeks after the onset of paralysis. The principal features measured were 12 months pre- and post-operative House-Brackmann (HB) grades and the presence of a direct intraoperative neural response (INR) prior to decompression procedure. Correlations between these parameters, and the time between symptom onset and surgery (within or later than 30 and 50 d) were statistically analyzed.

RESULTS

Of the 25 patients 13 (52%) exhibited good recovery (HB grade I or II) at 12 months-post-operatively. The timing of decompression generally did not significantly influence outcome but patients treated within 50 d of symptom onset enjoyed better outcomes than those treated later (p = .047). The presence of an INR significantly influenced outcomes (p = .0003).

CONCLUSIONS

The success of delayed transmastoid facial nerve decompression in RHS patients was not affected between 25-30 and 30-40 d from symptom onset but was compromised when the delay was >50 d. The presence or absence of an INR was a good predictor of post-operative prognosis.