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Vascular tumors (vascular malformations and hemangiomas) of the temporal bone are uncommon, and guidelines for their management have not been published. In an effort to develop an approach to their management, the present study examined the pathological, clinical, and surgical experience with ten of these lesions treated at the Otologic Medical Group, Inc., and St. Vincent Medical Center in Los Angeles from 1960 to 1980. Intratemporal vascular tumors occurred most frequently at two sites, the internal auditory canal and the geniculate ganglion. Histological features and clinical behavior did not correlate. Both vascular malformations and hemangiomata invaded the facial nerve. Surgical excision in these cases required severence and repair of the involved facial nerve. Complete surgical excision is the treatment of choice of vascular lesions of the temporal bone. [ABSTRACT FROM AUTHOR]

Vestibular schwannoma (VS) may present clinically in one of two forms: sporadic unilateral or hereditary bilateral. Almost all cases of familial transmission have been associated with the diagnosis of neurofibromatosis type II (NF-2). In this report, we describe nine families (18 individuals) presenting with unilateral VS without evidence of NF-2. In four of the nine families, the affected individuals were of parent-offspring relationship, in three families they were cousin-cousin, and in the remaining two families, they were sibling-sibling and aunt-nephew. No other members of the families were diagnosed with NF-2. There was no evidence for gender predilection or genomic imprinting among affected individuals. This study suggests that familial occurrence of unilateral VS may be genetically inherited as it occurs more commonly than would be estimated by chance alone. Future genetic studies will elucidate whether occurrence of unilateral VS in these families represents a variable expression of NF-2, chance occurrence of unilateral VS in families, or a new genetic disorder. [ABSTRACT FROM AUTHOR]

The pathoetiology of benign paroxysmal positional vertigo (BPPV) is controversial. Particulate matter within the posterior semicircular canal has been identified intraoperatively in patients with BPPV but has also been reported in non-BPPV patients at the time of translabyrinthine surgery (Parnes LS, McClure JA. Free-floating endolymphatic particles: a new operative finding during posterior semicircular canal occlusion. Laryngoscope 1992;102:988-92; Schuknecht HF, Ruby RRF. Cupulolithiasis. Adv Otorhinolaryngol 1973;20: 434-43; Kveton JF, Kashgarian M. Particulate matter within the membranous labyrinth: pathologic or normal? Am J Otol 1994;15:173-6). The nature of the particulate matter remains unknown. The purpose of this study was to prospectively examine the posterior semicircular canal of patients with and without a clinical history of BPPV for the presence of particulate matter. Seventy-three patients without BPPV symptoms undergoing labyrinthine surgery (vestibular schwannoma excision or labyrinthectomy) and 26 patients with BPPV undergoing the posterior semicircular canal occlusion procedure were compared. Additionally, 70 archived temporal bones without a history of BPPV were examined microscopically for the presence of particulate matter within the lumen of the membranous labyrinth. No particles were observed intraoperatively in any of the 73 patients without a history of BPPV. Particulate matter was observed in 8 of 26 patients at the time of the posterior semicircular canal occlusion procedure for intractable BPPV. Of the 70 temporal bones examined, 31 did not show significant postmortem changes and also did not demonstrate cupulolithiasis or canalithiasis. Particulate matter from within the membranous posterior semicircular canal was removed from one patient at the time of posterior semicircular canal occlusion for intractable BPPV symptoms and was examined by scanning electron microscopy. The particulate matter appeared morphologically consistent with degenerating otoconia. These data show a statistically significant association between the presence of particles within the posterior semicircular canal in this study and the symptom complex of BPPV. [ABSTRACT FROM AUTHOR]

Intracranial lipomas are rare tumors which may occur in the cerebellopontine angle (CPA) or internal auditory canal (IAC). Although seemingly innocuous in other parts of the body, lipomas within the CPA and IAC often involve the surrounding cranial nerves, making attempts at hearing conservation largely unsuccessful. In an attempt to differentiate the IAC lipoma from the more commonly found acoustic schwannoma, the preoperative imaging studies (magnetic resonance and computerized tomography) on five previously unreported cases of IAC lipomas were evaluated. Based on these studies, features were determined that may allow the surgeon to diagnose IAC lipomas preoperatively. These features will be discussed, as well as the surgical and pathological findings. [ABSTRACT FROM AUTHOR]

A retrospective analysis of 40 patients (49 ears) with congenital progressive sensorineural hearing loss who underwent endolymphatic sac surgery was performed. The inner ears were radiographically abnormal in 57% of operated ears. In the remaining cases, subtle malformations beyond the resolving power of radiographic studies were suspected. Early postsurgical hearing loss (defined as a loss greater than 10 dB in three-tone average or greater than 15% in speech discrimination score) was found in 29% of operated ears (14/49). However, only two of these patients lost all of their residual hearing postoperatively (2/49 or 4%). An enlarged endolymphatic sac was noted at surgery in 50% of those with significant postoperative hearing losses. Longer-term stability of hearing was assessed in 22 patients with bilateral inner-ear pathology who underwent surgery on one side only. A comparison of the hearing fate of the operated and nonoperated ears suggested no benefit from the surgical intervention when compared to the natural history of the disease. Based upon this experience, endolymphatic sac surgery for the purpose of hearing stabilization in patients with congenital malformations of the inner ear is no longer recommended. [ABSTRACT FROM AUTHOR]

In malignant external otitis (MEO), determining the anatomic extent of disease and evaluating the physiologic response to therapy remain a problem. Magnetic resonance imaging (MRI) has recently become available in limited clinical settings. Four patients with MEO were evaluated using MRI, computerized tomography (CT), technetium-99 (Tc-99) bone scanning, and gallium-67 citrate (Ga-67 citrate) scanning. MRI is superior to CT, Tc-99 bone scanning, and Ga-67 citrate scanning in evaluating the anatomic extent of soft tissue changes in MEO. MRI alone cannot be relied upon to determine the physiologic response to therapy. MRI can, however, serve as a valuable guide to the interpretation of Tc-99 bone and Ga-67 citrate scans, and in this respect, MRI is extremely useful in the treatment of MEO. [ABSTRACT FROM AUTHOR]

Cholesterol granuloma of the petrous apex is a newly recognized clinical entity distinct from cholesteatoma. Cholesterol granuloma usually produces symptoms of trigeminal, facial, and abducens nerve palsy and may not affect the auditory nerve. The characteristic computerized cranial tomographic (CCT) finding is a nonenhancing, smooth-walled, expansile lesion that is isodense with brain tissue in a patient with bilaterally well pneumatized mastoids and petrous apices. Treatment is limited to drainage of the cyst and insertion of a stent for permanent aeration of the petrous apex. Of ten cases of cholesterol granuloma of the petrous apex recently diagnosed at the Otologic Medical Group, the correct preoperative diagnosis was made in nine patients on the basis of CCT findings. Six of the nine patients had serviceable hearing preoperatively; serviceable hearing was maintained postoperatively in five patients. [ABSTRACT FROM AUTHOR]

The management of facial nerve injury resulting from temporal bone fracture continues to be a topic of discussion. The indications for surgery as well as the proper timing and extent of surgical exploration are the principal questions debated. This study reviews a large series of patients (26), treated for facial paralysis following a longitudinal temporal bone fracture. The most frequent site of injury was the area of the geniculate ganglion. The injury to the facial nerve was often severe. We recommend early exploration in these cases when electrical studies indicate a severe injury. In most cases a combined mastoid and middle fossa approach is required. [ABSTRACT FROM AUTHOR]

Objective: We evaluated hearing outcomes in patients with sudden hearing loss and vestibular schwannoma who underwent a hearing preservation operation for tumor resection in an effort to determine whether a history of sudden sensorineural hearing loss has an impact on subsequent hearing preservation surgery., Methods: Retrospective chart review of 45 patients operated between 1990 and 1998. Patients were divided into "Recovery" (n = 22) and "No Recovery" (n = 23) groups based on preoperative hearing recovery. Hearing preservation was assessed using the AAO-HNS hearing classification system., Results: Measurable hearing was preserved in 73% of patients, with 47% having good postoperative hearing (AAO-HNS Classes A-B). There was no significant difference in hearing outcome from patients presenting with progressive hearing loss (45% Classes A-B). There was also no difference in postoperative hearing between the "Recovery" and "No Recovery" groups., Conclusions: Patients with sudden hearing loss and vestibular schwannoma have the same chance of hearing preservation after tumor removal as those with progressive loss. Preoperative recovery of hearing is not predictive of hearing preservation. Available data support the nerve compression theory as the mechanism of sudden hearing loss in patients with vestibular schwannoma.

The case of a 55-year-old woman with a middle ear mass is presented. The preoperative diagnostic workup, including an audiogram and imaging studies, and the histopathologic findings of the tumor are reviewed. The tumor, a schwannoma, arose from Jacobson's nerve in the middle ear. The surgical anatomy of Jacobson's nerve and the surgical approach to this tumor and to other tumors of the middle ear space are discussed. Tumors of the tympanic cavity are rare, with the exception of cholesteatoma; otherwise, the most common among them are paraganglioma and facial nerve neuroma. This report represents the first documented case of a schannoma arising from Jacobson's nerve in the tympanic cavity.

Objective/hypothesis: To determine the heritable proportion of paraganglioma (PGL) and identify clinical features associated with heritable PGL., Study Design: Patients diagnosed with head and neck PGLs, identified retrospectively through clinical otolaryngology practices and/or participation in previous PGL research studies, were given a medical and family history questionnaire., Methods: Questionnaire information was used to classify participants as having "heritable" or "non-heritable" cases of PGL. Classification of the participants identified through otolaryngology clinics was used to estimate the heritable proportion of PGL. Statistical analysis was performed to identify significant differences in the clinical characteristics of the heritable versus non-heritable groups., Results: Among the otolaryngology clinic population, 35% were classified as having heritable PGL. Individuals with heritable PGL were younger on average than those with non-heritable PGL. The majority of non-heritable participants were female, but there was an equal gender ratio among the heritable participants. Individuals diagnosed with a carotid body tumor (CBT) were 5.8 times more likely to be classified as heritable than those diagnosed with PGL at other anatomic locations., Conclusions: Approximately 35% of individuals who present to an otolaryngologist with a head and neck PGL have inherited a predisposition for this growth. Among individuals diagnosed with head and neck PGL, those diagnosed with CBT are 5.8 times more likely to have an inherited predisposition than those diagnosed with PGL at other anatomic locations.

The purpose of this study was to determine the association of intraoperative auditory brainstem responses (ABRs) and near-field cochlear nerve action potentials (CNAPs) with postoperative hearing preservation in acoustic tumor surgery. Thirty-three consecutive patients undergoing middle fossa surgery had intraoperative surface ABR and direct CNAP assessments. Postoperatively, hearing was assessed. Hearing preservation was defined as any measurable hearing at any frequency and also by the American Academy of Otolaryngology--Head and Neck Surgery (AAO-HNS) hearing preservation classification system. The presence of an ABR or CNAP was associated with hearing preservation and the absence of an ABR, and CNAP was associated with no hearing preservation in 75.6 percent of the cases. The presence of either the ABR or CNAP was not related to AAO-HNS class outcome. ABR and CNAP had a useful rate of prediction of hearing preservation surgery outcome. However, in nearly one-quarter of the cases, no association between ABR or CNAP responses and hearing preservation was found. This finding must be taken into account when determining the clinical usefulness of these techniques.