1

Introduction

Sensorineural hearing loss, tinnitus and recurrent vertigo constitute the hallmark symptoms of Meniere’s Disease (MD) . Fluctuation of a predominantly low frequency or flat threshold elevation for all frequencies and reduced word discrimination are the usual audiometric patterns recorded in this inner ear disorder which has been assumed to be idiopathic. Occasionally a predominantly high frequency loss is recorded with early MD. Usually MD is clinically manifest in one ear with the chance of becoming bilateral ranging from 15% to 50% .

Endolymphatic hydrops (EH) has been described as the responsible pathology in MD . Since that description the medical and surgical treatment of MD has been directed at reducing the volume of endolymph . Unfortunately, these approaches have had equivocal success in the control of vertigo and recovery of hearing . The additional hypothesis that the release of neurophysiologically toxic potassium ion into the perilymphatic space following ruptures of a distended membranous labyrinth is responsible for vestibular and cochlear deficits does not adequately account for some histopathologic findings in the temporal bones (TB) from patients with MD. These include fibrosis under the stapes footplate ( Fig. 1 ) and a significant loss of vestibular neurons . Careful assessment of the TB in MD indicates that EH is not responsible for the clinical presentation in MD . This long established histopathologic finding can be regarded as a marker for the underlying pathologic process in MD.

Photo micrograph of fibrosis under stapes footplate (FP) producing distention of saccular membrane (S). Mag = 80 ×.

Furthermore, the pattern of vestibular nerve degeneration is not consistent with an effect caused by diffuse contamination of the perilymphatic space surrounding the sense organs. Potassium toxicity to the vestibular sense organs would induce a diffuse pattern of neural degeneration because the dendrites of vestibular ganglion cells are scattered in a haphazard fashion. However, the focal axonal degeneration observed in MD can only be produced by loss of a tight cluster of ganglion cells because of the organization of vestibular axons and their ganglion cells ( Fig. 2 ). Such a cluster of adjacent ganglion cells is characteristic of viral neuropathies where virus is spread between adjacent neurons over contact of their cell membranes ( Fig. 3 ).

Photo of focal axonal degeneration in the vestibular nerve trunk of patient with MD. Mag = 350 ×.

Cluster of ganglion cells undergoing degeneration with collagen replacement (arrow heads). Mag = 130 ×.

This neural pattern of focal axonal degeneration has been observed in TB from patients with MD and with vestibular neuronitis (VN) . The subsequent demonstration by transmission electron microscopy (TEM) of fully formed viral particles in the cytoplasm of vestibular ganglion cells excised from patients with MD provides direct evidence to support the indirect evidence of HSV DNA in MD ( Fig. 4 ). This evidence has formed the basis for an antiviral treatment approach in patients with MD and VN . Over the past 10 years this approach demonstrated control of vertigo in 90% of patients . The effect on hearing loss in MD has not been described. The purpose of this report is to demonstrate recovery of the sensorineural hearing loss in patients with MD treated with antiviral drugs.

(A) EM of ganglion cell from same patient. Arrows point to virus particles enclosed in transport vesicles. Mag = 13,000 ×. (B) Electron micrograph (EM) of vestibular ganglion cell excised from patient with MD. Arrow points to a virus particle being enclosed in a transport vesicle M = Mitochondrion. Mag = 13,000 ×.

2

Materials and Methods

Thirty one new patients who satisfied the requirements for a diagnosis of MD were seen from January 1st, 2012 to December 31st, 2012. The requirements included: Recurrent vertigo with duration of one-half to several hours; sensorineural hearing loss in one or both ears; tinnitus and aural fullness in the involved ear. All patients had magnetic resonance imaging with contrast enhancement of the brain which was reported as negative for neoplastic or vascular lesions. These patients had been treated previously by outside otolaryngologists and had failed to relieve vertigo and hearing loss by the use of low salt diet and diuretics. Some had received anti allergy medication and one (no. 6 in Table 1 ) had undergone bilateral sequential endolymphatic sac decompression.

Two forms of acyclovir were used. Acyclovir or valacyclovir (Valtrex) was used based on expense and insurance coverage. Hepatic and renal functions were cleared as normal. Complete Otolaryngological examination was normal.

Hearing test including air and bone frequency thresholds and word discrimination scores were recorded. Tympanograms were normal. The hearing test was repeated after 1–2 months of treatment; then at 5–6 months, 1 year and 2 years. Antiviral therapy was initiated only if the patient complained of recurring episodes of vertigo that had an impact on their home or work activities. Hearing was judged to be improved if there was a decrease in the original pure tone average (PTA) for 0.5, 1, 2 and 3 kHz of 15 db or more and/or an increase in the speech discrimination (SD) of 20% or more. These criteria are more demanding than those required by the committee on hearing and equilibrium for Meniere’s disease (PTA: 10 db; SD: 15%) .

The schedule for administration of antiviral was as follows: Acyclovir: 800 mg Tab TID for 3 weeks and re-examined. If there is improvement in vertigo, reduce to 800 mg BID/3 weeks, then 800 mg daily. Valacyclovir: 1 g tab. TID for 3 weeks and re-examined. If there are improvements in vertigo reduce to 1 g BID/3 weeks, then 1 g daily. Patients remain on 1 tab/daily for one year. Then a discussion with patient is held to determine continuation. All patients elected to remain on the daily dose of 1 tablet.

2

Materials and Methods

Thirty one new patients who satisfied the requirements for a diagnosis of MD were seen from January 1st, 2012 to December 31st, 2012. The requirements included: Recurrent vertigo with duration of one-half to several hours; sensorineural hearing loss in one or both ears; tinnitus and aural fullness in the involved ear. All patients had magnetic resonance imaging with contrast enhancement of the brain which was reported as negative for neoplastic or vascular lesions. These patients had been treated previously by outside otolaryngologists and had failed to relieve vertigo and hearing loss by the use of low salt diet and diuretics. Some had received anti allergy medication and one (no. 6 in Table 1 ) had undergone bilateral sequential endolymphatic sac decompression.

Table 1

Hearing Improved.

Patient		PTA db			SD %		Change		Vertigo Control	Duration Meniere’s Disease (YR)
		Side	PRE	POST	PRE	POST	SRT db	SD %
1.	68 F	L	LF 40	15	CNT	CNT	25	–	+	0.5
2.	62 M	L	FL 73	61	32%	74%	12	42	+	1
3.	31 F	L	LF 50	11	64%	96%	39	32	+	1
4.	50 F	L	FL 53	27	64%	96%	26	32	+	2
5.	36 F	L	LF 25	8	96%	96%	17	4	+	5
6.	61 M	R	FL 58	20	66%	94%	38	28	+	10
		L	FL 40	40	82%	86%	0	4
7.	34 F	L	LF 45	15	100%	100%	30	0	+	0.5
8.	47 F	L	LF 35	10	88%	92%	25	4	+	1
9.	58 M	L	LF 53	30	52%	84%	23	32	+	0.5
10.	65 M	R	LF 21	10	68%	92%	11	24	+	0.5
11.	59 F	R	FL 18	11	96%	96%	7	0	+	5
		L	FL 53	40	54%	92%	13	38
12.	66 F	L	FL 68	15	20%	96%	53	76	+	0.1
										AVG = 2.4

Only gold members can continue reading. Log In or Register to continue

Share this:

• Click to share on Twitter (Opens in new window)
• Click to share on Facebook (Opens in new window)

Related

Related posts:

1. Recurrent facial palsy in Melkersson Rosenthal syndrome: total facial nerve decompression is effective to prevent further recurrence
2. Predictors of repeated “no-showing” to clinic appointments
3. Case presentation of an intranasal ectopic tooth in a pediatric patient
4. New tumor phenotypes reported in the larynx in the last decades: a critique

Stay updated, free articles. Join our Telegram channel

Join