Facial Nerve Grading System 2.0

OBJECTIVE

To present an updated version of the original Facial Nerve Grading Scale (FNGS), commonly referred to as the House-Brackmann scale.

STUDY DESIGN

Controlled trial of grading systems using a series of 21 videos of individuals with varying degrees of facial paralysis.

RESULTS

The intraobserver and interobserver agreement was high among the original and revised scales. Nominal improvement is seen in percentage of exact agreement of grade and reduction of instances of examiners differing by more then one grade when using FNGS 2.0. FNGS 2.0 also offers improved agreement in differentiating between grades 3 and 4.

CONCLUSION

FNGS 2.0 incorporates regional scoring of facial movement, providing additional information while maintaining agreement comparable to the original scale. Ambiguities regarding use of the grading scale are addressed.

Natural history vs. surgery for Menière's disease

Menière's disease has an episodic course, and certain patients undergo spontaneous remission of their vertigo. A retrospective study of patients treated from 1974 to 1983 was undertaken to evaluate the long-term outcome of patients with Menière's disease for whom surgery was recommended, comparing those who had a surgical procedure with a similar group of patients who declined surgery. The surgical procedures performed were endolymphatic subarachnoid shunt (ELS), retrolabyrinthine vestibular neurectomy (RVN), middle fossa vestibular neurectomy (MFVN), and transmeatal cochleo-vestibular neurectomy (CVN). We used a questionnaire, made up according to the 1985 American Academy of Otolaryngology (AAO) criteria, for reporting results for Menière's disease treatment, and compared patients who were offered surgery but declined (N = 50) with those who underwent surgery (N = 83). The data were analyzed statistically. Initial evaluation, which included air and bone conduction audiometry, speech discrimination, electronystagmography (ENG), frequency of vertigo attacks per month, and disability, showed both groups to be comparable at the outset. Of the non-operated group 57% had complete control of vertigo at 2 years; 71% had complete control after an average of 8.3 years. After an ELS, 40% of patients had complete control of vertigo after 2 years; 70% had complete control after an average of 8.7 years. After a neurectomy (RVN or CVN), 93% had complete control of vertigo (average followup, 4.4 years). These results indicate statistically that the ELS procedure does not alter the long-term natural course of vertigo control in Menière's disease, whereas both the RVN and CVN significantly improve the patient's chance of being permanently free of vertigo attacks.

Readaptation of the vestibulo-ocular reflex relieves the mal de debarquement syndrome

The mal de debarquement syndrome (MdDS), a continuous feeling of swaying, rocking, and/or bobbing, generally follows travel on the sea. The associated symptoms cause considerable distress. The underlying neural mechanisms are unknown, and to date there have been no effective treatments for this condition. Results in monkeys and humans suggested that MdDS was caused by maladaptation of the vestibulo-ocular reflex (VOR) to roll of the head during rotation. We studied 24 subjects with persistent MdDS (3 males, 21 females; 19.1 ± 33 months). Physical findings included body oscillation at 0.2 Hz, oscillating vertical nystagmus when the head was rolled from side-to-side in darkness, and unilateral rotation during the Fukuda stepping test. We posited that the maladapted rocking and the physical symptoms could be diminished or extinguished by readapting the VOR. Subjects were treated by rolling the head from side-to-side while watching a rotating full-field visual stimulus. Seventeen of the 24 subjects had a complete or substantial recovery on average for approximately 1 year. Six were initially better, but the symptoms recurred. One subject did not respond to treatment. Thus, readaptation of the VOR has led to a cure or substantial improvement in 70% of the subjects with MdDS. We conclude that the adaptive processes associated with roll-while-rotating are responsible for producing MdDS, and that the symptoms can be reduced or resolved by readapting the VOR.

Routine identification of the facial nerve using electrical stimulation during otological and neurotological surgery

We routinely identify the facial nerve to avoid facial nerve injury during most otologic surgery. Since 1985, we have used a facial nerve stimulator/monitor as an added safety feature in 383 consecutive otologic and neurotologic cases. In our last 30 middle-ear, 8 retrolabyrinthine vestibular neurectomy, and 14 acoustic neuroma cases we used the monopolar stimulator probe-tip to determine threshold currents needed to produce facial twitch. Stimulation thresholds varied according to the amount of soft tissue or bone overlying the facial nerve. The stimulator was useful for predicting dehiscences in the bony facial canal during middle-ear and mastoid surgery. The exposed facial nerve usually stimulated at a level less than 0.1 mA (mean 0.05 mA), and the horizontal facial nerve covered by bone stimulated at 0.25 mA or greater (mean 0.6 mA). The stimulator was also used to predict the amount of bone overlying the vertical facial nerve at the annulus. An approximate relationship of 1.0 mA of threshold current to 1.0 mm of bony covering was found. After acoustic neuroma surgery, the stimulation threshold of the facial nerve at the brain stem helped predict postoperative facial function. Cases with current thresholds of 0.3 mA or less resulted in normal facial function. During ear surgery, routine identification of the facial nerve with the aid of a facial nerve stimulator will help avoid facial nerve injury.

The singular canal: a valuable landmark in surgery of the internal auditory canal

The singular canal transmits the posterior ampullary nerve between the inferior part of the internal auditory canal (IAC) and ampulla of the posterior semicircular canal. The anatomy of the singular canal was studied in temporal bone dissections, in surgical dissections, and in high-resolution computerized tomography scans. Measurements were taken for distances between the origin of the singular canal in the IAC, the porus acousticus, the vestibule, and posterior canal ampulla. The location and importance of the singular canal are demonstrated for retrosigmoid-IAC vestibular neurectomy, retrosigmoid acoustic neuroma surgery, and transcochlear cochleovestibular neurectomy. The main purpose for the use of the retrosigmoid approach to the internal auditory canal during vestibular neurectomy and excision of acoustic neuromas is preservation of hearing. A major concern when the contents of the internal auditory canal are exposed through this approach is fenestration of the labyrinth, which results in sensorineural hearing loss. In the retrosigmoid approach, the singular canal has been found to be a vital landmark in prevention of fenestration during surgery of the internal auditory canal.

An evolution of approach in vestibular neurectomy

Since introducing the retrolabyrinthine vestibular neurectomy in 1978, we have performed 78 procedures with good results. In 1985 we introduced the retrosigmoid-IAC vestibular neurectomy, which allows a more complete transection of the vestibular nerves within the internal auditory canal (IAC). Vertigo control has been excellent; however, in 75% of patients, postoperative headaches have been a significant problem. In 1987, the best aspects of the two procedures were incorporated and the combined retrolab-retrosigmoid vestibular neurectomy was developed. The procedure is similar to the RVN in that all bone covering the lateral venous sinus is removed. It differs from the RVN in that a limited mastoidectomy is performed and the dura is opened just behind the LVS. The LVS is retracted forward, exposing the cerebellopontine angle. This allows the surgeon the option to section the vestibular nerve in either the CP angle or the IAC, depending upon the presence or absence of a cochieovestibular cleavage plane in the CP angle. The results have been good and the incidence of headache has been reduced to 10%. The technique, results, and complications are reported here.

Transmastoid Repair of Spontaneous Cerebrospinal Fluid Leaks

Objective  Determine the efficacy of using a purely transmastoid approach for the repair of spontaneous cerebrospinal fluid (CSF) leaks and further elucidate the relationship of elevated body mass index (BMI) and skull base thickness in our patient population. Method  We conducted a retrospective chart review of patients treated for spontaneous temporal bone CSF leaks at our tertiary care institution from the years 2006 to 2015. Cases were categorized as primary or secondary. We analyzed success rates, length of stay, use of lumbar drains, BMIs, and rates of meningitis. Skull base thickness was compared with BMI in each case. Results  We identified 26 primary operations for spontaneous CSF leaks and 7 secondary operations. Twenty-three of 33 repairs were performed via the transmastoid approach alone with an 87% success rate (20/23). Of the10 repairs including a middle cranial fossa (MCF) or combined MCF-transmastoid approach, 2 failed for an 80% success rate (8/10). Five transmastoid repairs underwent placement of a lumbar drain versus all 10 repairs employing an intracranial exposure. Average length of stay for those undergoing a transmastoid approach (1.7 days) was significantly shorter than for patients undergoing a MCF repair (6.3 days). Four patients presented with meningitis. Average BMI was 35.3. No correlation was established between BMI and skull base thickness ( R²  = 0.00011). Conclusion  The transmastoid approach is effective in the majority of cases and prevents the need for an intracranial operation, resulting in lower morbidity and a shorter length of stay. We believe that this is the preferred primary approach in most patients with spontaneous CSF leaks.

Compartmentation of intracellular water in multicellular tumor spheroids: diffusion and relaxation NMR

Diffusion and relaxation of water in C6 glioma and MLS human ovarian carcinoma spheroids were measured from 1D projections acquired using a 2D diffusion-relaxation correlation pulse sequence and processed by non-negative least-square (NNLS) analysis. Systematic underestimation of I(s) and ADC(s) were observed for I(s)/(I(s) + I(f)) < 0.001. In the presence of spheroids, two apparent diffusion coefficient (ADC) compartments were observed, where ADC(f), ADC(s), and I(f), I(s) are the respective ADCs and signal intensities of the fast and slow compartments. These compartments differed also in their T(2) relaxation (ADC(s) = 0.5-0.74 x 10(-5) cm(2)/s, T(2) = 36-45 ms; and ADC(f) = 2.2-2.8 x 10(-5) cm(2)/s, T(2) = 280-316 ms). The two ADC compartments and the slow T(2) compartment were consistent with slow exchange. The fast T(2) compartment showed a drift with diffusion weighting, suggesting that it represents water exchanging between compartments that differ in their ADC and T(2). Both ADC(s) and I(s) were markedly attenuated with increasing diffusion time (Delta) for Delta < 100 ms, and increased at longer Delta. These results are consistent with restricted diffusion and fast relaxation of intracellular water for short diffusion time (T(1)' = 46.6 ms), and with predominant extracellular contribution to ADC(s) at longer diffusion times. Magn Reson Med 46:68-77, 2001.

The state of tinnitus after inner ear surgery

A retrospective study of several procedures--for either treatment of vertigo or resection of acoustic neuromas--was performed to determine their effect on tinnitus. Subjective ratings of the state of tinnitus (resolution, improvement, maintenance, or deterioration) were obtained by questionnaire. Surgical procedures performed for correction of vertigo frequently alter tinnitus. In general, procedures that conserve hearing--namely, retrolabyrinthine vestibular neurectomy (RVN), middle fossa vestibular neurectomy (MFVN), and endolymphatic shunt procedures (ELS)--have a 50% to 65% chance of helping relieve tinnitus and up to a 22% chance of worsening tinnitus. When there is no serviceable hearing, cochleovestibular neurectomy (CVN) offers the best cure rate for tinnitus (76%) and the least chance of worsening tinnitus (3%). When hearing is minimal and the patient complains of tinnitus, a CVN--rather than a labyrinthectomy--should be recommended. However, when useful hearing is present, a CVN is not usually recommended for relief of tinnitus, since the actual cure rates are only 35%. When vertigo is not a complaint, there is currently no surgical procedure known that can be recommended for the treatment of tinnitus.

Endovascular Management of Sigmoid Sinus Diverticulum

Sigmoid sinus diverticulum (SSD) is a rare vascular disorder due to dehiscence of the sigmoid plate. It may be associated with prediverticular venous sinus stenosis (SS) and usually presents as pulsatile tinnitus. The mechanism of development of the SSD and tinnitus from a sinus diverticulum and associated SS is unclear. Previous case reports have suggested that remodeling of the venous system targeting the stenosis, elimination of the diverticulum, or both, have resulted in symptom relief. We present a case of SSD with SS, treated by stenting of the stenosis along with coil embolization of the diverticulum, resulting in complete relief of symptoms. We have also reviewed the literature and discussed the evolution of management from open surgical treatment to endovascular treatment.

Optical imaging with a high-resolution microendoscope to identify cholesteatoma of the middle ear

OBJECTIVES/HYPOTHESIS

High-resolution optical imaging is an imaging modality that allows visualization of structural changes in epithelial tissue in real time. Our prior studies using contrast-enhanced microendoscopy to image squamous cell carcinoma in the head and neck demonstrated that the contrast agent, proflavine, has high affinity for keratinized tissue. Thus, high-resolution microendoscopy with proflavine provides a potential mechanism to identify ectopic keratin production, such as that associated with cholesteatoma formation, and distinguish between uninvolved mucosa and residual keratin at the time of surgery.

STUDY DESIGN

Ex vivo imaging of histopathologically confirmed samples of cholesteatoma and uninvolved middle ear epithelium.

METHODS

Seven separate specimens collected from patients who underwent surgical treatment for cholesteatoma were imaged ex vivo with the fiberoptic endoscope after surface staining with proflavine. Following imaging, the specimens were submitted for hematoxylin and eosin staining to allow histopathological correlation.

RESULTS

Cholesteatoma and surrounding middle ear epithelium have distinct imaging characteristics. Keratin-bearing areas of cholesteatoma lack nuclei and appear as confluent hyperfluorescence, whereas nuclei are easily visualized in specimens containing normal middle ear epithelium. Hyperfluorescence and loss of cellular detail is the imaging hallmark of keratin, allowing for discrimination of cholesteatoma from normal middle ear epithelium.

CONCLUSIONS

This study demonstrates the feasibility of high-resolution optical imaging to discriminate cholesteatoma from uninvolved middle ear mucosa based on the unique staining properties of keratin. Use of real-time imaging may facilitate more complete extirpation of cholesteatoma by identifying areas of residual disease. Laryngoscope, 2012.

The Effects of Compensatory Auditory Stimulation and High-Definition Transcranial Direct Current Stimulation (HD-tDCS) on Tinnitus Perception - A Randomized Pilot Study

Background

Tinnitus correlates with elevated hearing thresholds and reduced cochlear compression. We hypothesized that reduced peripheral input leads to elevated neuronal gain resulting in the perception of a phantom sound.

Objective

The purpose of this pilot study was to test whether compensating for this peripheral deficit could reduce the tinnitus percept acutely using customized auditory stimulation. To further enhance the effects of auditory stimulation, this intervention was paired with high-definition transcranial direct current stimulation (HD-tDCS).

Methods

A randomized sham-controlled, single blind study was conducted in a clinical setting on adult participants with chronic tinnitus (n = 14). Compensatory auditory stimulation (CAS) and HD-tDCS were administered either individually or in combination in order to access the effects of both interventions on tinnitus perception. CAS consisted of sound exposure typical to daily living (20-minute sound-track of a TV show), which was adapted with compressive gain to compensate for deficits in each subject's individual audiograms. Minimum masking levels and the visual analog scale were used to assess the strength of the tinnitus percept immediately before and after the treatment intervention.

Results

CAS reduced minimum masking levels, and visual analog scale trended towards improvement. Effects of HD-tDCS could not be resolved with the current sample size.

Conclusions

The results of this pilot study suggest that providing tailored auditory stimulation with frequency-specific gain and compression may alleviate tinnitus in a clinical population. Further experimentation with longer interventions is warranted in order to optimize effect sizes.

Long-term results of transmeatal cochleovestibular neurectomy: an analysis of 100 cases

One hundred patients have been treated over a 13-year period with a transmeatal approach to the internal auditory canal for cochleovestibular neurectomy. Ninety-one of these patients have followup of more than 3 months (average, 4.67 years). The most common indication for the procedure was Meniere's disease (71%). Chronic labyrinthitis, usually following stapes, middle ear, or mastoid surgery, was the next most common indication. Patients with the preoperative diagnosis of Meniere's disease had better results in the curing of vertigo (89%) than those having chronic labyrinthitis (68%). Overall, vertigo was cured in 84% of patients and markedly improved in another 15.1%. Tinnitus was relieved or improved in 65% of all patients and in 67% of patients with Meniere's disease. Mild unsteadiness was commonly noticed postoperatively, but only 11% described this as severe. Eighty percent of these latter patients reported unsteadiness preoperatively. Complications were uncommon and temporary: one case of delayed facial paresis that recovered completely, one CSF leak, and one wound infection. There were no cases of permanent facial paralysis or meningitis. The advantages of the transmeatal approach to the IAC for CVN over labyrinthectomy without CVN are assurance of complete labyrinthine denervation, increased likelihood of improved tinnitus, practice at sectioning the posterior ampullary nerve (PAN), and the ability to inspect the internal auditory canal for a small tumor or other pathology. We recommend this procedure for treatment of unilateral vestibular dysfunction in patients with no serviceable hearing.

Verrucous carcinoma of the temporal bone

Verrucous carcinoma, a familiar lesion of the oral cavity and larynx, is distinctly rare in the ear. We report five cases of verrucous carcinoma of the temporal bone, each of which fulfills Ackerman's histologic and biologic criteria. Only three cases of verrucous carcinoma of the ear have been previously reported. Most cases of verrucous cancers of the head and neck demonstrate a lack of nodal involvement, relatively slow growth potential, local invasiveness, and responsiveness to surgical treatment. In our five cases of verrucous carcinoma of the temporal bone, three had a biologic behavior similar to other verrucous tumors, while two cases were unusually aggressive. Three patients were treated surgically and had favorable outcomes, while the remaining two were treated with combination therapy. These cases highlight the difficulty in diagnosis and treatment as well as the lack of understanding of the biologic behavior of this rare otologic entity.

Matched Comparison of Hearing Outcomes in Patients With Vestibular Schwannoma Treated With Stereotactic Radiosurgery or Observation

BACKGROUND

Previous studies comparing hearing outcomes in patients managed with stereotactic radiosurgery (SRS) and a watch-and-wait strategy were limited by small sample sizes that prevented controlling for potential confounders, including initial hearing status, tumor size, and age.

OBJECTIVE

To compare hearing outcomes for patients with vestibular schwannomas (VS) managed with observation and SRS while controlling for confounders with propensity score matching.

METHODS

Propensity score matching was used to compare 198 patients with unilateral VS with initial serviceable hearing (99 treated with SRS and 99 managed with observation alone) and 116 with initial class A hearing (58 managed with SRS and 58 with observation), matched by initial hearing status, tumor volume, age, and sex. Kaplan-Meier survival methods were used to compare risk of losing class A and serviceable hearing.

RESULTS

Between patients with VS managed with SRS or observation alone, there was no significant difference in loss of class A hearing (median time 27.2 months, 95% CI 16.8-43.4, and 29.2 months, 95% CI 20.4-62.5, P = .88) or serviceable hearing (median time 37.7 months, 95% CI 25.7-58.4, and 48.8 months, 95% CI 38.4-86.3, P = .18). For SRS patients, increasing mean cochlear dose was not related to loss of class A hearing (hazard ratio 1.3, P = .17) but was associated with increasing risk of serviceable hearing loss (hazard ratio of 1.5 per increase in Gy, P = .017).

CONCLUSION

When controlling for potential confounders, there was no significant difference in loss of class A or serviceable hearing between patients managed with SRS or with observation alone.

Tuberculous Otitis Media: Report of 2 Cases on Long Island, N.Y., and a Review of all Cases Reported in the United States from 1990 through 2003

We report 2 cases of tuberculous otitis media that were diagnosed at Stony Brook University Hospital in New York since 1999. Both patients were women, aged 30 and 31 years. One patient had grown up in Russia, the other was a native-born American who had never left the East Coast region of the United States. Both patients had been symptomatic for many months; one complained of chronic otorrhea, and the other reported otorrhea, hearing loss, and discomfort. Neither patient responded to medical management, and both ultimately underwent surgery. One was diagnosed after surgical pathology revealed acid-fast bacilli on frozen-section analysis. In the other, pathology revealed chronic inflammation and granulomata, but stains were negative and her diagnosis was delayed for almost 2 years. We also review 9 other cases of tuberculous otitis media in the United States that have been reported in the literature since 1990. Our review suggests that the number of cases is rising in areas where tuberculosis is most common—that is, in major U.S. cities. Although 3 of these 9 cases occurred as reactivation disease in immigrants, most might have occurred as a result of local transmission. Clinicians should maintain a high degree of suspicion for tuberculosis in patients with chronic otitis symptoms, particularly those who are at higher risk of exposure to tuberculosis.

Two cases of bilateral congenital cholesteatoma--usual and unusual presentations

Bilateral congenital cholesteatomas are rare. We present the 8th and 9th case of this entity in the literature. One of these cases is especially unusual. In that patient an ear that had been documented as normal, both radiographically and clinically, was found to have a large cholesteatoma 18 months after the contralateral ear had been treated for the same disease. The theories of the pathogenesis of this entity are also reviewed. Our cases support several of these theories. In fact, in one of the patients, it is possible that a different etiology was involved in each ear. Incidental note is made of the fact that three of the nine reported cases of bilateral congenital cholesteatoma have occurred in the same geographic locale.

Modern Hearing Preservation Outcomes After Vestibular Schwannoma Stereotactic Radiosurgery

BACKGROUND

For patients with vestibular schwannoma (VS), stereotactic radiosurgery (SRS) has proven effective in controlling tumor growth while hearing preservation remains a key goal.

OBJECTIVE

To evaluate hearing outcomes in the modern era of cochlear dose restriction.

METHODS

During the years 2013 to 2018, 353 patients underwent Gamma knife surgery for VS at our institution. We followed 175 patients with pre-SRS serviceable hearing (Gardner-Robertson Score, GR 1 and 2). Volumetric and dosimetry data were collected, including biological effective dose, integral doses of total and intracanalicular tumor components, and hearing outcomes.

RESULTS

The mean age was 56 years, 74 patients (42%) had a baseline GR of 2, and the mean cochlear dose was 3.5 Gy. The time to serviceable hearing loss (GR 3-4) was 38 months (95% CI 26-46), with 77% and 62% hearing preservation in the first and second years, respectively. Patients optimal for best hearing outcomes were younger than 58 years with a baseline GR of 1, free canal space ≥0.041 cc (diameter of 4.5 mm), and mean cochlear dose <3.1 Gy. For such patients, hearing preservation rates were 92% by 12 months and 81% by 2 years, staying stable for >5 years post-SRS, significantly higher than the rest of the population.

CONCLUSION

Hearing preservation after SRS for patients with VS with serviceable hearing is correlated to the specific baseline GR score (1 or 2), age, cochlear dose, and biological effective dose. Increased tumor-free canal space correlates with better outcomes. The most durable hearing preservation correlates with factors commonly associated with smaller tumors away from the cochlea.

In vivo prediction of vascular susceptibility to vascular susceptibility endothelial growth factor withdrawal: magnetic resonance imaging of C6 rat glioma in nude mice

One of the hallmarks of tumor neovasculature is the prevalence of immature vessels manifested by the low degree of recruitment of vascular mural cells such as pericytes and smooth muscle cells. This difference in the architecture of the vascular bed provides an important therapeutic window for inflicting tumor-selective vascular damage. Here we demonstrate the application of gradient echo magnetic resonance imaging (MRI) for noninvasive in vivo mapping of vascular maturation, manifested by the ability of mature vessels to dilate in response to elevated levels of CO2. Histological alpha-actin staining showed a match between dilating vessels detected by MRI and vessels coated with smooth muscle cells. Switchable, vascular endothelial growth factor (VEGF)-overexpressing tumors (C6-pTET-VEGF rat glioma s.c. tumors in nude mice) displayed high vascular function and significant vascular damage upon VEGF withdrawal. However, damage was restricted to nondilating vessels, whereas mature dilating tumor vessels were resistant to VEGF withdrawal. Thus, MRI provides in vivo visualization of vascular maturity and prognosis of vascular obliteration induced by VEGF withdrawal.