The future of otology.

BACKGROUND: The field of otology is increasingly at the forefront of innovation in science and medicine. The inner ear, one of the most challenging systems to study, has been rendered much more open to inquiry by recent developments in research methodology. Promising advances of potential clinical impact have occurred in recent years in biological fields such as auditory genetics, ototoxic chemoprevention and organ of Corti regeneration. The interface of the ear with digital technology to remediate hearing loss, or as a consumer device within an intelligent ecosystem of connected devices, is receiving enormous creative energy. Automation and artificial intelligence can enhance otological medical and surgical practice. Otology is poised to enter a new renaissance period, in which many previously untreatable ear diseases will yield to newly introduced therapies. OBJECTIVE: This paper speculates on the direction otology will take in the coming decades. CONCLUSION: Making predictions about the future of otology is a risky endeavour. If the predictions are found wanting, it will likely be because of unforeseen revolutionary methods.

Signed, sealed and delivered: "big tobacco" in Hollywood, 1927-1951.

OBJECTIVE: Smoking in movies is associated with adolescent and young adult smoking initiation. Public health efforts to eliminate smoking from films accessible to youth have been countered by defenders of the status quo, who associate tobacco imagery in "classic" movies with artistry and nostalgia. The present work explores the mutually beneficial commercial collaborations between the tobacco companies and major motion picture studios from the late 1920s through the 1940s. METHODS: Cigarette endorsement contracts with Hollywood stars and movie studios were obtained from internal tobacco industry documents at the University of California, San Francisco (UCSF) Legacy Tobacco Documents Library and the Jackler advertising collection at Stanford. RESULTS: Cigarette advertising campaigns that included Hollywood endorsements appeared from 1927 to 1951, with major activity in 1931-2 and 1937-8 for American Tobacco Company's Lucky Strike, and in the late 1940s for Liggett & Myers' Chesterfield. Endorsement contracts and communication between American Tobacco and movie stars and studios explicitly reveal the cross-promotional value of the campaigns. American Tobacco paid movie stars who endorsed Lucky Strike cigarettes US$218,750 in 1937-8 (equivalent to US$3.2 million in 2008) for their testimonials. CONCLUSIONS: Hollywood endorsements in cigarette advertising afforded motion picture studios nationwide publicity supported by the tobacco industry's multimillion US dollar advertising budgets. Cross-promotion was the incentive that led to a synergistic relationship between the US tobacco and motion picture industries, whose artefacts, including "classic" films with smoking and glamorous publicity images with cigarettes, continue to perpetuate public tolerance of onscreen smoking. Market-based disincentives within the film industry may be a solution to decouple the historical association between Hollywood films and cigarettes.

Neurofibromatosis 2 and malignant mesothelioma.

Mutations of the neurofibromatosis 2 (NF2) tumor suppressor gene cause the inherited disorder NF2 and are also common in malignant mesothelioma, which is not a characteristic feature of NF2. The authors report an asbestos-exposed person with NF2 and malignant mesothelioma. Immunohistochemical analysis of the mesothelioma confirmed loss of expression of the NF2 protein, and comparative genomic hybridization revealed losses of chromosomes 14, 15, and 22, and gain of 7. The authors propose that a person with a constitutional mutation of an NF2 allele is more susceptible to mesothelioma.

MR imaging in two cases of subacute denervation change in the muscles of facial expression.

SUMMARY: Denervation changes in muscle following damage to cranial and peripheral nerves can be observed on both CT and MR imaging studies. These findings are well described for cranial nerves (CN) V, X, XI, and XII. The CT findings of denervation atrophy due to CN VII dysfunction have been reported. We describe the MR imaging findings in two patients with perineural spread of tumor along CN VII. Both patients showed T2 prolongation and postcontrast enhancement in muscles of facial expression, suggestive of subacute denervation changes.

A century of eighth nerve surgery.

STUDY DESIGN: A scholarly review of over 70 original papers from the late 19th and early 20th centuries. RESULTS: Although many neurotologists consider vestibular nerve section to be a recent innovation, eighth nerve division dates back to the dawn of intracranial surgery. Although surgery of peripheral nerves (e.g., repair after injury) is ancient, intracranial nerve surgery began in the latter part of the 19th century with fifth nerve division for tic douloureux. By analogy, it was reasoned that hyperactivity of the eighth nerve (initially tinnitus and later vertigo) could be relieved by dividing this nerve. In 1898, Fedor Krause (1856-1937) of Berlin attempted the first eighth nerve section. This patient, as did many during this era, died shortly after the operation. Most of the survivors had facial palsy. These innovative early surgeons used a variety of approaches, including the suboccipital, middle fossa, and transtemporal routes. After an initial burst of excitement during the first decade of the century, poor results led to few procedures being performed through the second and third decades. Throughout this era, there was much debate about the relative merits of labyrinthectomy (introduced by Milligan and Lake in 1904) as opposed to eighth nerve division. In the late 1920s, the prolific Walter E. Dandy (1886-1946) of Baltimore repopularized eighth nerve section and ultimately performed 607 procedures between 1927 and 1946. Although Dandy achieved a high vertigo control rate and reduced the mortality rate to <1%, he had a high rate of facial nerve weakness (9.1% transient, 4.2% permanent). Remarkably, the latter outcome was never published in his numerous papers on the subject, but was first revealed in a 1951 retrospective survey, which appeared some 5 years after his death. Selective division of the vestibular fibers was introduced by Kenneth G. McKenzie (1892-1963) of Toronto in 1931. At least 11 sizable series appeared in the literature before the introduction of microsurgical vestibular nerve section by William F. House (b. 1923) of Los Angeles in 1960. CONCLUSIONS: The introduction and progressive refinement of eighth nerve section played a central role in the evolution of operative neurotology. Many of the most vigorous debates of recent years (e.g., the choice of operative route, the optimal site of division, and the relative role of inner ear surgery vs. nerve surgery) have antecedents in the controversies of the distant past.

Lesions of the internal auditory canal and cerebellopontine angle in an only hearing ear: is surgery ever advisable?

OBJECTIVE: To define the indications for surgery in lesions of the internal auditory canal (IAC) and cerebellopontine angle (CPA) in an only hearing ear. STUDY DESIGN: Retrospective case series. SETTING: Tertiary referral center. PATIENTS: Seven patients with lesions of the IAC and CPA who were deaf on the side opposite the lesion. Five patients had vestibular schwannoma (VS), and one each had meningioma and progressive osseous stenosis of the IAC, respectively. The opposite ear was deaf from three different causes: VS (neurofibromatosis type 2 [NF2]), sudden sensorineural hearing loss, idiopathic IAC stenosis. INTERVENTION(S): Middle fossa removal of VS in five, retrosigmoid resection of meningioma in one, and middle fossa IAC osseous decompression in one. MAIN OUTCOME MEASURE: Hearing as measured on pure-tone and speech audiometry. RESULTS: Preoperative hearing was class A in four patients, class B in two, and class C in one. Postoperative hearing was class A in three patients, class B in one, class C in two, and class D in one. CONCLUSIONS: Although the vast majority of neurotologic lesions in an only hearing ear are best managed nonoperatively, in highly selected cases surgical intervention is warranted. Surgical intervention should be considered when one or more of the following circumstances is present: (1) predicted natural history of the disease is relatively rapid loss of the remaining hearing, (2) substantial brainstem compression has evolved (e.g., large acoustic neuroma), and/or (3) operative intervention may result in improvement of hearing or carries relatively low risk of hearing loss (e.g., CPA meningioma).

Is the entire fundus of the internal auditory canal visible during the middle fossa approach for acoustic neuroma?

HYPOTHESIS: To determine the degree to which the fundus of the internal auditory canal (IAC) can be visualized during the middle fossa approach (MFA). BACKGROUND: Conventional wisdom states that the MFA provides excellent access to the IAC from the porus acusticus to the fundus. On the basis of observations derived from a substantial surgical experience, it became obvious that a variable fraction of the fundus lies obscure from the surgeon's line of sight during the MFA because of (1) the overhand of the transverse crest and/or (2) the immobility of the facial nerve at its entry into the fallopian canal. METHODS: Intraoperative measurements were performed in ten cases to determine the typical angle of view to the fundus of the IAC in the MFA. This angle of view was projected onto coronal computed tomography scans of 40 temporal bones. Measurements of the IAC were made to determine the amount of fundus that could not be directly visualized during a MF exposure. RESULTS: On the basis of a surgical line of sight, the fraction of the inferior compartment of the canal that could not be directly visualized because of overhand of the transverse crest ranged from 14% to 34% (median 25%). CONCLUSIONS: Complete resection of IAC tumors involving the fundus via the MFA requires some degree of blind dissection. Specialized tools and techniques are required to minimize the risk of neural injury during this indirect dissection. Inspection of the fundus with either mirror or endoscope is often necessary to exclude the possibility of retained tumor fragments.

Extradural temporal lobe retraction in the middle fossa approach to the internal auditory canal: biomechanical analysis.

HYPOTHESIS: The middle fossa (MF) approach is undergoing a marked resurgence in vestibular schwannoma surgery as a hearing conservation technique. It is widely recognized that the extradural temporal lobe retractors used in this procedure, despite their cleverness of design, could be improved. METHODS: To identify the characteristics of an ideal MF retractor, a systematic analysis of the safety and functionality of four commonly used retractors (House-Urban, Fisch, Garcia-Ibanez, and UCSF) in a human anatomical model was conducted. Intensity of temporal lobe compression, width of exposure, angle of visualization, obstruction to instrument access, ergonomic convenience of use, and adaptability to other subtemporal procedures (e.g. lesions of Meckel's cave and cavernous sinus) were quantified. RESULTS: Because the intracranial portions of the retractors are similar, the force transmitted to the brain differed little among the four retractors. Numerous differences were noted in the ergonomics of use and versatility of the various designs. CONCLUSIONS: The optimal MF retractor would incorporate the best features of each of the existing systems: the integral suction of the Garcia-Ibanez, the bone contour-following design of the Fisch retractor base, the unobtrusiveness and adaptability of the UCSF, and the three-plane adjustability of the vintage House-Urban. Evolution of an "ideal" MF retractor requires further technical refinements and the development of an experimental model of extradural brain retraction to assess the optimal strategy for obtaining exposure while minimizing the risk for temporal lobe injury.