First results of a novel adjustable-length ossicular reconstruction prosthesis in temporal bones

OBJECTIVES/HYPOTHESIS

The performance of an ossicular replacement prosthesis (ORP) is influenced by its alignment and appropriate tension between the tympanic membrane and the stapes footplate. A novel ORP with a flexible element that potentially allows for length adjustment in situ is presented and tested for acoustic performance.

STUDY DESIGN

Laser Doppler vibrometry in fresh human cadaveric temporal bones was used to test the acoustic performance of the adjustable ORP relative to standard prostheses used for ossiculoplasty.

METHODS

The three-dimensional (3D) velocity of the stapes posterior crus was measured in the 0.2- to 20-kHz range using a Polytec CLV-3D laser Doppler vibrometer. The middle ear cavity was accessed through a facial recess approach. After measuring the normal response, the incus was removed and stapes velocity was measured in the disarticulated case, then after insertion of the new prosthesis, a conventional prosthesis (Kurz BELL Dusseldorf type), and a sculpted autologous incus prosthesis in each temporal bone. The 3D stapes velocity transfer function (SVTF) was calculated for each case and compared.

RESULTS

The novel ORP design restored stapes velocity to within 6 dB (on average) of the intact response. No significant differences in 3D-SVTF were found between the new, conventional, or autologous ORPs.

CONCLUSIONS

The inclusion of an in situ adjustable element into the ORP design did not adversely affect its acoustic performance. The adjustable element may increase the ease of achieving optimal ORP placement, especially through a facial recess approach.

LEVEL OF EVIDENCE

NA Laryngoscope, 126:2559-2564, 2016.

Clinical Practice Guideline

The American Academy of Otolaryngology—Head and Neck Surgery Foundation (AAO-HNSF) has published a supplement to this issue featuring the new Clinical Practice Guideline: Tinnitus. To assist in implementing the guideline recommendations, this article summarizes the rationale, purpose, and key action statements. The 13 recommendations developed address the evaluation of patients with tinnitus, including selection and timing of diagnostic testing and specialty referral to identify potential underlying treatable pathology. It will then focus on the evaluation and treatment of patients with persistent primary tinnitus, with recommendations to guide the evaluation and measurement of the impact of tinnitus and to determine the most appropriate interventions to improve symptoms and quality of life for tinnitus sufferers.

Clinical Practice Guideline

Objective

Tinnitus is the perception of sound without an external source. More than 50 million people in the United States have reported experiencing tinnitus, resulting in an estimated prevalence of 10% to 15% in adults. Despite the high prevalence of tinnitus and its potential significant effect on quality of life, there are no evidence-based, multidisciplinary clinical practice guidelines to assist clinicians with management. The focus of this guideline is on tinnitus that is both bothersome and persistent (lasting 6 months or longer), which often negatively affects the patient’s quality of life. The target audience for the guideline is any clinician, including nonphysicians, involved in managing patients with tinnitus. The target patient population is limited to adults (18 years and older) with primary tinnitus that is persistent and bothersome.

Purpose

The purpose of this guideline is to provide evidence-based recommendations for clinicians managing patients with tinnitus. This guideline provides clinicians with a logical framework to improve patient care and mitigate the personal and social effects of persistent, bothersome tinnitus. It will discuss the evaluation of patients with tinnitus, including selection and timing of diagnostic testing and specialty referral to identify potential underlying treatable pathology. It will then focus on the evaluation and treatment of patients with persistent primary tinnitus, with recommendations to guide the evaluation and measurement of the effect of tinnitus and to determine the most appropriate interventions to improve symptoms and quality of life for tinnitus sufferers.

Action Statements

The development group made a strong recommendation that clinicians distinguish patients with bothersome tinnitus from patients with nonbothersome tinnitus. The development group made a strong recommendation against obtaining imaging studies of the head and neck in patients with tinnitus, specifically to evaluate tinnitus that does not localize to 1 ear, is nonpulsatile, and is not associated with focal neurologic abnormalities or an asymmetric hearing loss. The panel made the following recommendations: Clinicians should (a) perform a targeted history and physical examination at the initial evaluation of a patient with presumed primary tinnitus to identify conditions that if promptly identified and managed may relieve tinnitus; (b) obtain a prompt, comprehensive audiologic examination in patients with tinnitus that is unilateral, persistent (≥ 6 months), or associated with hearing difficulties; (c) distinguish patients with bothersome tinnitus of recent onset from those with persistent symptoms (≥ 6 months) to prioritize intervention and facilitate discussions about natural history and follow-up care; (d) educate patients with persistent, bothersome tinnitus about management strategies; (e) recommend a hearing aid evaluation for patients who have persistent, bothersome tinnitus associated with documented hearing loss; and (f) recommend cognitive behavioral therapy to patients with persistent, bothersome tinnitus. The panel recommended against (a) antidepressants, anticonvulsants, anxiolytics, or intratympanic medications for the routine treatment of patients with persistent, bothersome tinnitus; (b) Ginkgo biloba, melatonin, zinc, or other dietary supplements for treating patients with persistent, bothersome tinnitus; and (c) transcranial magnetic stimulation for the routine treatment of patients with persistent, bothersome tinnitus. The development group provided the following options: Clinicians may (a) obtain an initial comprehensive audiologic examination in patients who present with tinnitus (regardless of laterality, duration, or perceived hearing status); and (b) recommend sound therapy to patients with persistent, bothersome tinnitus. The development group provided no recommendation regarding the effect of acupuncture in patients with persistent, bothersome tinnitus.

Temporal Bone Radiology: Beyond the Basics

Program Description:

Through this interactive presentation, the audience is exposed to challenging temporal bone radiology cases and offered strategies to improve their interpretation. We will cover key findings for chronic ear disease and conductive hearing loss, lateral skull base lesions, and the petrous apex. The emphasis is placed on subtle but pertinent findings on computed tomography and magnetic resonance imaging examinations and their importance in creating and narrowing a differential diagnoses. We will present guidelines to aid in the efficient acquisition and interpretation of imaging for patients with common otologic symptoms such as vertigo, sudden hearing loss, and pulsatile tinnitus.

Educational Objectives:

(1) Interpret key radiographic findings for common pathologic conditions of the temporal bone. (2) Order appropriate radiographic tests to evaluate common conditions and understand the strengths and limitations of various imaging modalities.

Managing the Unexpected in Otologic Surgery

Program Description:

Sponsored by the American Neurotology Society, this interactive presentation aims to provide general practitioners tips and techniques employed by experts in management of intraoperative complications encountered during common otology cases such as tympanoplasty, tympanomastoidectomy, and stapedotomy. The panelists will present illustrative cases and discuss best practice approaches to intraoperative cerebrospinal fluid (CSF) leak and encephaloceles, facial nerve injury, vascular complications, stapedotomy challenges, ossicular chain and external auditory canal damage, and inner ear violation.

Educational Objectives:

(1) Recognize unexpected circumstances and anatomic variations that could lead to complications in otologic surgery. (2) Manage intraoperative complications such as facial nerve palsy, vascular injury, encephaloceles, CSF leaks, postoperative sensorineural hearing loss, and vertigo.

Temporal Bone Radiology: Beyond the Basics

Program Description:

Through this interactive presentation, the audience is exposed to challenging temporal bone radiology cases and offered strategies to improve his or her interpretation. We will cover key findings for chronic ear disease and conductive hearing loss, lateral skull base lesions, and the petrous apex. The emphasis is placed on subtle but pertinent findings on computed tomography (CT) and MRI examinations and their importance in creating and narrowing a differential diagnosis. We will present guidelines to aid in the efficient acquisition and interpretation of imaging for patients with common otologic symptoms such as vertigo, sudden hearing loss, and pulsatile tinnitus.

Educational Objectives:

1) Interpret key radiographic findings for common pathologic conditions of the temporal bone. 2) Order appropriate radiographic tests to evaluate common conditions and understand the strengths and limitations of various imaging modalities.

Spontaneous Cerebrospinal Fluid Leak through the Posterior Aspect of the Petrous Bone

Spontaneous cerebrospinal fluid (CSF) leak through the posterior fossa (PF) aspect of the petrous bone is exceedingly rare. A case series allows analysis of etiologies and how they may differ from the more common middle fossa (MF) route of leakage. The design was a retrospective case series. The setting was a tertiary care institution. A series of three patients with PF spontaneous CSF leaks was identified. High-resolution imaging (CT and MRI) and intraoperative observations were evaluated. Both in this series and in previously reported cases, patients share the demographics typically found in the MF leak population. In our series, two patterns of PF CSF leak were identified: (1) large unilateral with cerebellar encephalocele and (2) small punctate defects just lateral to the endolymphatic sac. Two presented with simultaneous MF and PF leaks suggesting a shared etiology, at least in some cases, with a role for increased intracranial pressure. In spontaneous CSF leaks, it is important to evaluate the posterior petrous bone along with the tegmen. The concomitant appearance of MF with PF leaks points out the risk that repair via MF craniotomy could fail to identify a leakage site in the vicinity of the endolymphatic sac.

Facial nerve outcomes after surgery for large vestibular schwannomas: do surgical approach and extent of resection matter?

OBJECT

The object of this study was to evaluate facial nerve outcomes in the surgical treatment of large vestibular schwannomas (VSs; ≥ 2.5 cm maximal or extrameatal cerebellopontine angle diameter) based on both the operative approach and extent of tumor resection.

METHODS

A PubMed search was conducted of English language studies on the treatment of large VSs published from 1985 to 2011. Studies were then evaluated and included if they contained data regarding the size of the tumor, surgical approach, extent of resection, and postoperative facial nerve function.

RESULTS

Of the 536 studies initially screened, 59 full-text articles were assessed for eligibility, and 30 studies were included for analysis. A total of 1688 tumor resections were reported. Surgical approach was reported in 1390 patients and was significantly associated with facial nerve outcome (ϕ= 0.29, p < 0.0001). Good facial nerve outcomes (House-Brackmann Grade I or II) were produced in 62.5% of the 555 translabyrinthine approaches, 65.2% of the 601 retrosigmoid approaches, and 27.4% of the 234 extended translabyrinthine approaches. Facial nerve outcomes from translabyrinthine and retrosigmoid approaches were not significantly different from each other, but both showed significantly more good facial nerve outcomes, compared with the extended translabyrinthine approach (OR for translabyrinthine vs extended translabyrinthine = 4.43, 95% CI 3.17-6.19, p < 0.0001; OR for retrosigmoid vs extended translabyrinthine = 4.98, 95% CI 3.57-6.95, p < 0.0001). There were 471 patients for whom extent of resection was reported. There was a strong and significant association between degree of resection and outcome (ϕ= 0.38, p < 0.0001). Of the 80 patients receiving subtotal resections, 92.5% had good facial nerve outcomes, compared with 74.6% (n = 55) and 47.3% (n = 336) of those who received near-total resections and gross-total resections, respectively. In the 2-way comparison of good versus suboptimal/poor outcomes (House-Brackmann Grade III-VI), subtotal resection was significantly better than near-total resection (OR = 4.21, 95% CI 1.50-11.79; p = 0.004), and near-total resection was significantly better than gross-total resection (OR = 3.26, 95% CI 1.71-6.20; p = 0.0002) in producing better facial nerve outcomes.

CONCLUSIONS

In a pooled patient population from studies evaluating the treatment of large VSs, subtotal and near-total resections were shown to produce better facial nerve outcomes when compared with gross-total resections. The translabyrinthine and retrosigmoid surgical approaches are likely to result in similar rates of good facial nerve outcomes. Both of these approaches show better facial nerve outcomes when compared with the extended translabyrinthine approach, which is typically reserved for especially large tumors. The reported literature on treatment of large VSs is extremely heterogeneous and minimal consistency in reporting outcomes was observed.

Clinical Consensus Statement

Objective

To develop a consensus statement on the appropriate use of computed tomography (CT) for paranasal sinus disease.

Subjects and Methods

A modified Delphi method was used to refine expert opinion and reach consensus by the panel.

Results

After 3 full Delphi rounds, 33 items reached consensus and 16 statements were dropped because of not reaching consensus or redundancy. The statements that reached consensus were grouped into 4 categories: pediatric sinusitis, medical management, surgical planning, and complication of sinusitis or sinonasal tumor. The panel unanimously agreed with 13 of the 33 statements. In addition, at least 75% of the panel strongly agreed with 14 of 33 statements across all of the categories.

Conclusions

For children, careful consideration should be taken when performing CT imaging but is needed in the setting of treatment failures and complications, either of the pathological process itself or as a result of iatrogenic (surgical) complications. For adults, imaging is necessary in surgical planning, for treatment of medical and surgical complications, and in all aspects of the complete management of patients with sinonasal and skull base pathology.

Spontaneous Cerebrospinal Fluid Leak through the Posterior Aspect of the Petrous Bone

Objective: Spontaneous cerebrospinal fluid (CSF) leak through the posterior fossa aspect of the petrous bone (PF) is very rare. A case series allows analysis of possible etiologies and how they may differ from the more common middle fossa (MF) route of leakage.

Method: A series of 3 patients with PF spontaneous temporal bone CSF leaks is described. High-resolution imaging (CT & MRI) and intraoperative observation characterize the anatomical characteristics of the pathway.

Results: This series of patients did share the demographics typically found in the MF leak population. Two patterns of PF CSF leak were identified: large unilateral with cerebellar encephalocele and bilateral small defects just lateral to the endolymphatic sac. Two out of our 3 patients presented with simultaneous MF and PF leaks suggesting the possibility of a shared etiology, at least in some cases, with a role for increased intracranial pressure.

Conclusion: In spontaneous CSF leaks it is important to evaluate the posterior petrous bone along with the tegmen. The concomitant appearance of MF with PF leaks points out the risk that repair via MF craniotomy could fail to identify a leakage site in the vicinity of the endolymphatic sac.

Functional hair cell mechanotransducer channels are required for aminoglycoside ototoxicity

Aminoglycosides (AG) are commonly prescribed antibiotics with potent bactericidal activities. One main side effect is permanent sensorineural hearing loss, induced by selective inner ear sensory hair cell death. Much work has focused on AG's initiating cell death processes, however, fewer studies exist defining mechanisms of AG uptake by hair cells. The current study investigated two proposed mechanisms of AG transport in mammalian hair cells: mechanotransducer (MET) channels and endocytosis. To study these two mechanisms, rat cochlear explants were cultured as whole organs in gentamicin-containing media. Two-photon imaging of Texas Red conjugated gentamicin (GTTR) uptake into live hair cells was rapid and selective. Hypocalcemia, which increases the open probability of MET channels, increased AG entry into hair cells. Three blockers of MET channels (curare, quinine, and amiloride) significantly reduced GTTR uptake, whereas the endocytosis inhibitor concanavalin A did not. Dynosore quenched the fluorescence of GTTR and could not be tested. Pharmacologic blockade of MET channels with curare or quinine, but not concanavalin A or dynosore, prevented hair cell loss when challenged with gentamicin for up to 96 hours. Taken together, data indicate that the patency of MET channels mediated AG entry into hair cells and its toxicity. Results suggest that limiting permeation of AGs through MET channel or preventing their entry into endolymph are potential therapeutic targets for preventing hair cell death and hearing loss.

Distal parotid duct pseudocyst as a result of blunt facial trauma

The sequelae of sharp trauma to the parotid duct, such as sialocele and salivary fistula, are well known. In contrast, complications of blunt trauma to the parotid duct are not as common. A search of the English-language literature revealed 2 cases of parotid pseudocysts caused by blunt trauma. Although no well-known management protocol exists for complications of blunt trauma to the parotid duct, the treatment modalities for sharp trauma complications potentially could be applied. We describe a case of a blunt-trauma-induced distal parotid duct pseudocyst that remained refractory to conservative management, including repeated aspiration and cannulation of the duct. After characterizing and localizing the pseudocyst with sialography and cross-sectional imaging, we performed a surgical repair. This repair involved marsupialization of the parotid duct to the level of the pseudocyst. The edges of the opening of the proximal duct and the pseudocyst were sutured to the oral mucosa, and a small intraoral drain was left in the pseudocyst to prevent collapse and abscess formation. The drain was removed after 5 days, and the patient experienced no further problems during 14 months of follow-up.

Bivalve cartilage inlay myringoplasty: an office-based procedure for closing small to medium-sized tympanic membrane perforations

OBJECTIVE

To determine whether bivalve inlay cartilage-perichondrium myringoplasty (BCM) is successful in closing tympanic membrane perforations in an office setting.

STUDY DESIGN

Retrospective case review.

SUBJECTS AND METHODS

Adult patients with chronic perforations underwent BCM under local and topical anesthesia. Success was defined as complete closure of perforation at follow-up of at least 1 month. Predictors of success were identified by comparing the success and failure groups on pre- and postoperative pure tone average (PTA), patient demographics (age, gender), and characteristics of the perforations (size, location, duration, etiology).

RESULTS

A total of 145 procedures were performed and the patients were followed for 1 to 78 months. The success rate for perforations smaller than 4 mm was 75 percent. Size of the perforation, and pre- and postoperative PTAs were significantly different between the two groups. The only significant predictors of success were preoperative PTA and size of perforation.

CONCLUSIONS

BCM is a viable option for closure of small and medium-sized perforations in an office setting.

In vivo imaging of mammalian cochlear blood flow using fluorescence microendoscopy

AIMS

We sought to develop techniques for visualizing cochlear blood flow in live mammalian subjects using fluorescence microendoscopy.

BACKGROUND

Inner ear microcirculation appears to be intimately involved in cochlear function. Blood velocity measurements suggest that intense sounds can alter cochlear blood flow. Disruption of cochlear blood flow may be a significant cause of hearing impairment, including sudden sensorineural hearing loss. However, inability to image cochlear blood flow in a nondestructive manner has limited investigation of the role of inner ear microcirculation in hearing function. Present techniques for imaging cochlear microcirculation using intravital light microscopy involve extensive perturbations to cochlear structure, precluding application in human patients. The few previous endoscopy studies of the cochlea have suffered from optical resolution insufficient for visualizing cochlear microvasculature. Fluorescence microendoscopy is an emerging minimally invasive imaging modality that provides micron-scale resolution in tissues inaccessible to light microscopy. In this article, we describe the use of fluorescence microendoscopy in live guinea pigs to image capillary blood flow and movements of individual red blood cells within the basal turn of the cochlea.

METHODS

We anesthetized eight adult guinea pigs and accessed the inner ear through the mastoid bulla. After intravenous injection of fluorescein dye, we made a limited cochleostomy and introduced a compound doublet gradient refractive index endoscope probe 1 mm in diameter into the inner ear. We then imaged cochlear blood flow within individual vessels in an epifluorescence configuration using one-photon fluorescence microendoscopy.

RESULTS

We observed single red blood cells passing through individual capillaries in several cochlear structures, including the round window membrane, spiral ligament, osseous spiral lamina, and basilar membrane. Blood flow velocities within inner ear capillaries varied widely, with observed speeds reaching up to approximately 500 microm/s.

CONCLUSION

Fluorescence microendoscopy permits visualization of cochlear microcirculation with micron-scale optical resolution and determination of blood flow velocities through analysis of video sequences.

Death following tonsillectomy in a child with Williams syndrome

Williams syndrome (WS) is an uncommon genetic syndrome due to a deletion of several genes on chromosome 7. The syndrome is associated with dysmorphic facies, neurological manifestations, idiopathic hypercalcemia, and cardiac abnormalities, particularly supravalvular aortic stenosis (SVAS). Children with Williams syndrome may have chronic serous otitis media and/or obstructive sleep apnea. Hyperacusis is also commonly seen in these children. We report a case of sudden death at the time of tonsillectomy/adenoidectomy and bilateral tympanostomy tube placement in a child with Williams syndrome. All children with Williams syndrome should have a thorough cardiac evaluation before undergoing general anesthesia for any otolaryngologic procedure.

Endoscopic selective neck dissection in a porcine model

OBJECTIVE

To investigate the feasibility of accomplishing a selective neck dissection (SND) endoscopically.

STUDY DESIGN

Prospective, nonrandomized experimental investigation in a porcine model.

METHODS

Unilateral endoscopic SNDs were performed in Yorkshire pigs. A spacious operative pocket was developed using a combination of hernia balloon expansion followed by low-pressure (4 mm Hg) carbon dioxide insufflation. The sternomastoid muscle, thymus, submandibular gland, lymph nodes, and fibrofatty tissue were removed in a procedure approximating a human SND. Data (operative time, blood loss, arterial blood gas values, weight of the specimen, and complications) were prospectively recorded. The specimens were analyzed by a pathologist, and the number and size of lymph nodes were recorded.

RESULTS

Fourteen endoscopic SNDs were successfully performed. No conversions to open surgery were necessary. The median operative time was 131 minutes (range, 95-235 minutes). The median estimated blood loss was 4 mL (range, 0-150 mL). The mean +/- SD specimen weight was 42.9 +/- 8.3 g; the mean number +/- SD of nodes retrieved from the neck specimen was 4.8 +/- 2.2, and the mean +/- SD maximal nodal dimension was 2.4 +/- 0.5 cm. The arterial PCO2 increased by an average of only 3.9 mm Hg from the beginning to the end of the surgery; correspondingly, the pH fell by only 0.02. There were no major complications, and no animals had to be euthanized prior to the completion of the procedure.

CONCLUSIONS

Endoscopic neck dissection in a porcine model can be accomplished with a combination of strategies to overcome the dilemma of creating and maintaining an operative pocket. The merger of SND with endoscopic technology offers the promise of truly minimally invasive surgery for the node-negative neck.