Acoustic Neuroma and Glomus tumor Dr Hitesh Verma Anatomy Pathology Firm, well encapsulated Microscopically shows two type of characteristic patternAntoni type A & B Antoni A- orderly arrangement of parallel cells with dark staining fusiform nuclei arranged in bundles or whorls separated by relatively acellular fibrous tissue Antoni B- loose reticular arrangement with fewer cellular elements and more disorderly arranged nuclei Clinical features I. II. III. IV. V. 5 stages Otological stage- changes confined to vestibulocochlear and to limited extent facial nerve. It includes all intrameatal tm and extrameatal tm<2cm Trigeminal N involvement- >=2cm Brain stem and cerebellar compression Rising intracranial pressure Terminal stage Clinical features Hearing loss Usually patient present with a gradual, progressive, unilateral, or asymmetrical high frequency sensorineural hearing loss sudden onset sensorineural hearing loss Tinnitus It is usually high pitched, continuous, and unilateral or asymmetric Vertigo Clinical features Trigeminal nerve dysfunction It manifest as hypesthesia, paraesthesia, or rarely anaesthesis, typically in the mid-facial region Absent corneal reflex Clinical features Facial nerve dysfunction The weakness is typically gradual in onset 10% Histelberger’s signhypesthesia of the concha or external auditory canal floor. This is because the sensory fibers are less resistant to the effect of compression and consequently manifest earlier Diagnostic Testing Audiogram Unilateral or asymmetrical sensorineural hearing loss U-shaped or low tone patterns of loss are less common Diagnostic Testing Tympanometry Absent stapedial reflex stapedial reflex decay (greater than 50% return to base line in 10 sec) Diagnostic Testing Electronystamography determine whether the inferior of superior vestibular nerve is the site of origin for the vestibular schwannoma Caloric testing reveals the status of the horizontal semicircular and the superior vestibular nerve Diagnostic Testing Auditory brain stem response It is a sensitive test with a sensitivity of 90% to 100% The specificity of ABR testing ranges from 54% to 78% Imaging Treatment options The treatment options surgical resection radiation therapy observation Observation with sequential MRI only hearing ear in patients with advanced age and limited life expectancy, significant cardiovascular, pulmonary, or other systemic diseases Stereotactic radiation therapy Indications Small tumors > 3 cm Funtional hearing Older patients Medically unstable patients Previous resection Surgical treatment Surgical treatment The choice of approaches to the resection of vestibular schwannoma and other CPA tumor is a guided by the Degree of residual hearing Hearing status in the contralateral ear Location of the tumor Size of the tumor Cell type Age of the patient Trans-labrynthine Indications Non-serviceable hearing Retrosigmoid Indications Serviceable hearing Large tumors Compression of brainstem Middle Fossa Indications Small tumor Intracanallicular tumor Moderate CPA involvement Adequate hearing (SRT<50 db, Disc >50%) Complication of surgeries Though many complications occur, the important one include Intraoperative Cranial nerve injury- VII, V, Bleeding Brain edema Venous air embolism Cardiac arrythmias Brain herniation Identify the picture Another name? Award and year? Identify Nature interpretation centre, Chandigarh Logo represent ? Massage Anatomy and Function of Paraganglia Three bodies in each ear Jacobson’s nerve Arnold’s nerve in the adventitia of the jugular bulb blood supply is ascending pharyngeal artery via inferior tympanic and neuromeningeal branches Clinical features second most common temporal bone tumor (after acoustic neuroma) female:male ratio 5:1 median age 50-60 yrs (range 6 mo - 88 yrs) very slow growing spread locally in multidirectional fashion along paths of least resistance Clinical features Sign and symptoms can be divided into 3 type Those due to presence of tm in middle ear- conductive HL, aural polyp and aural discharge Those due to the vascularity of the tm- pulsatile tinnitus, aural bleeding Evaluation question pt regarding symptoms of secreting tumor(labile B/P, tachycardia, vascular HA) any suspicion, obtain urine for VMA, circulating catecholamines if positive, get abdominal CT to r/o concomitant adrenal pheochromocytoma Evaluation obtain audiogram Evaluation imaging should include CT temporal bone and MRI arteriography is helpful if surgery is planned helps in detecting multicentric tumors, identifies feeding vessels, allows for embolization Differential diagnosis Dehiscent or high riding jugular bulb Aberrant or laterally displaced ICA Acquired intratympanic carotid A aneurysm Treatment planning in general, healthy younger pts (<65 yrs) should consider surgical resection pts with large tumors with pre-existing ipsilateral CN deficits should be offered surgery pts >65 with poor pulmonary fxn or other complicating medical conditions should consider primary XRT Surgeries Anatomic classification Tympanic Tympanomastoid Jugular bulb Carotid artery Transdural Surgical approach Transcanal Mastoid-extended facial recess Mastoid-neck (possible limited Facial n rerouting) Infratemporal fossa Infratemporal fossa/intracranial Classification scheme devised by Antonio De la Cruz Transcanal approach Fisch approach Thank you…….
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