1/94. The leaking labyrinthine lesion resulting from direct force through the auditory canal: report of five cases.The leaking labyrinthine lesion is treated by conservative methods or surgical procedures. With respect to the stapes, the surgical treatment is controversial. Five cases of middle ear injuries accompanying oval window rupture are reported herein. In each case, direct force through the auditory canal damaged not only the ossicular chain but also the oval window. Initial symptoms were sudden hearing loss with significant conductive disturbance and various degrees of unsteadiness. Spontaneous horizontal nystagmus directed toward the uninvolved ear was observed in each case. Tympanic cavities were promptly explored under general anesthesia and oval window injuries were confirmed. In each case, the damaged stapes was temporally removed from the oval window. Perilymphatic leakage was recognized in each case. Two patients had subluxation of the stapes with a paucity leakage. Three had complete luxation of the stapes with a relatively huge oval window fistula. Disrupted oval windows were repaired with temporalis muscle fascial grafts that were inserted under the middle ear mucosae surrounding the oval windows. The stapes were replaced in the repaired oval windows, and the ossicular chains were reconstructed without artificial grafts. Vestibular dysfunctions disappeared within 7 days, and satisfactory audiologic results were obtained in each case.- - - - - - - - - - ranking = 1keywords = canal (Clic here for more details about this article) |
2/94. cholesteatoma extending into the internal auditory meatus.We report our experiences in managing a patient with cholesteatoma complicated by meningitis, labyrinthitis and facial nerve palsy. The antero-inferior half of the tympanum was aerated but the postero-superior portion of the tympanic membrane was tightly adherent to the promontry mucosa. An attic perforation was present at the back of the malleolar head. High-resolution computed tomography also uncovered a fistula in the lateral semicircular canal. Surgical exploration of the middle ear cavity demonstrated that both the vestibule and cochlea were filled with cholesteatoma, and the cholesteatoma extended into the internal auditory meatus through the lateral semi-circular canal fistula. The cholesteatoma was removed by opening the vestibule and cochlea with a preservation of the facial nerve. Post-operatively, an incomplete facial palsy remained, but has improved slowly. There is no sign of recurrence to date after a 3-year period of observation.- - - - - - - - - - ranking = 0.4keywords = canal (Clic here for more details about this article) |
3/94. Haemorrhage in the labyrinth caused by anticoagulant therapy: case report.We report a patient who experienced a severe vertiginous episode with bilateral tinnitus and progressive right-sided hearing loss. She had Marfan's disease and was on anticoagulant treatment. The fluid in the labyrinth gave higher signal than cerebrospinal fluid on T1-weighted images, suggesting haemorrhage. The radiological follow-up is discussed.- - - - - - - - - - ranking = 6.5863154880599E-5keywords = spinal (Clic here for more details about this article) |
4/94. Vestibular-evoked myogenic potentials in patients with dehiscence of the superior semicircular canal.Recently Minor and co-workers described patients with sound- and pressure-induced vertigo due to dehiscence of bone overlying the superior semicircular canal. Identifying patients with this "new" vestibular entity is important, not only because the symptoms can be very incapacitating, but also because they are surgically treatable. We present symptoms and findings for three such patients. On exposure to sounds, especially in the frequency range 0.5-1 kHz, they showed vertical/torsional eye movements analogous to a stimulation of the superior semicircular canal. They also showed abnormally large sound-induced vestibular-evoked myogenic potentials (VEMP), i.e. the short latency sternomastoid muscle response considered to be of saccular origin. The VEMP also had a low threshold, especially in the frequency range 0.5-1 kHz. However, in response to saccular stimulation by skull taps, i.e. when the middle ear route was bypassed, the VEMP were not enlarged. This suggests that the relation between the sound-induced and the skull tap-induced responses can differentiate a large but normal VEMP from an abnormally large response due to dehiscence of bone overlying the labyrinth, because only the latter would produce large sound-induced VEMP compared to those induced by skull taps.- - - - - - - - - - ranking = 1.2keywords = canal (Clic here for more details about this article) |
5/94. sound- and pressure-induced vertigo associated with dehiscence of the roof of the superior semicircular canal.In many types of peripheral vertigo, imaging is not part of the initial evaluation. We present a patient with sound- and pressure-induced vertigo associated with bony dehiscence of the roof of the superior semicircular canal. The diagnosis of this new entity can only be made by high-resolution coronal CT imaging of the temporal bones. In patients with this symptom complex, CT should be performed early in the diagnostic workup.- - - - - - - - - - ranking = 1keywords = canal (Clic here for more details about this article) |
6/94. Unilateral sensorineural hearing loss and its aetiology in childhood: the contribution of computerised tomography in aetiological diagnosis and management.OBJECTIVES: The objective of this study was to identify factors correlated with the CT outcome and to examine the contribution of the CT scan in the aetiological diagnosis and management of unilateral sensorineural hearing loss in childhood. methods: The records of 35 consecutively investigated patients by the audiology Department of Great Ormond Street Hospital between January 1996 and June 1998 were reviewed. The CT results, population sample characteristics, initiation of further investigations after the CT results and management decisions based on the CT results were tabulated and analysed. RESULTS: In a series of 35 consecutively investigated children with unilateral sensorineural hearing loss, 11 CT scans were identified as abnormal. The CT findings were: labyrinthitis ossificans (3), unilaterally dilated vestibular aqueduct (2), bilaterally dilated vestibular aqueduct (2), unilateral deformity of the cochlea ('Mondini') (1), unilateral severe labyrinthine dysplasia (1), unilateral markedly narrow internal acoustic meatus (1), bilaterally dilated lateral semicircular canals (1). The presence of progressive hearing loss was a significant predictor of abnormal CT outcome, while the severity of hearing loss was not. The CT scans offered valuable information regarding the aetiological diagnosis in all cases and, in addition, prompted the appropriate vestibular rehabilitation in three cases, further investigations in four (with dilated vestibular aqueduct) and hearing preservation counselling in two (bilateral DVA) (seven out of 35 = 20%). CONCLUSION: All children with unilateral sensorineural hearing loss should have a CT scan of the petrous pyramids/IAMs performed at some stage, as not only aetiology but also prognosis and management of these cases may be significantly influenced by the CT outcome.- - - - - - - - - - ranking = 0.2keywords = canal (Clic here for more details about this article) |
7/94. Cavernous angioma of the internal acoustic meatus--case report.A 39-year-old female presented with an intrameatal cavernous angioma manifesting as hearing loss and tinnitus in the right ear which progressed over 8 months. Magnetic resonance (MR) images revealed an intrameatal lesion as ultra-high intensity, nearly as bright as cerebrospinal fluid, on the T2-weighted images, and isointensity on the T1-weighted images. Computed tomography (CT) showed the mass accompanied by stippled patterns of calcification. The patient underwent surgery under a diagnosis of calcified acoustic neurinoma. Histological studies were compatible with cavernous angioma. Intrameatal cavernous angioma is a rare disease which requires differential diagnosis from the more common neurinoma or meningioma in this location. Intrameatal lesion with ultra-high intensity on T2-weighted MR imaging and stippled patterns of calcification on CT is more likely to be cavernous angioma than acoustic neurinoma. These neuroimaging features are important information in deciding the treatment strategy.- - - - - - - - - - ranking = 6.5863154880599E-5keywords = spinal (Clic here for more details about this article) |
8/94. Rotational vertebral artery occlusion syndrome with vertigo due to "labyrinthine excitation".Leftward head rotations in a patient with a rotational vertebral artery occlusion syndrome elicited recurrent uniform attacks of severe rotatory vertigo and tinnitus in the right ear. These attacks were accompanied by a mixed clockwise torsional downbeat nystagmus with a horizontal component toward the right. A transient ischemia of the right labyrinth probably induced the attacks and led to a combined transient excitation of the right anterior and horizontal semicircular canals as well as the cochlea.- - - - - - - - - - ranking = 0.2keywords = canal (Clic here for more details about this article) |
9/94. meningioma of the internal auditory canal with extension into the vestibule.Meningiomas account for approximately 18 to 19 per cent of all brain tumours. Although they can arise in numerous locations, meningiomas of the internal auditory canal (IAC) are rare. Most tumours that originate in the IAC are schwannomas of the VIIIth cranial nerve (acoustic neuromas). We report a case of a meningioma which appears to originate from the IAC and extends into the vestibule. The clinical findings and the radiographical features of meningiomas of the IAC are similar to those of acoustic neuromas. Pre-operative differentiation between acoustic neuromas and meningiomas of the IAC may be difficult.- - - - - - - - - - ranking = 1keywords = canal (Clic here for more details about this article) |
10/94. osteoma of the internal auditory canal.OBJECTIVE: To review presenting symptoms and illustrate management options for this uncommon lesion. DESIGN: Case series and literature review. SETTING: Tertiary referral center. patients: Three cases of osteoma of the internal auditory canal are presented. Additional cases from the literature, diagnosed by radiographic appearance or gross description, are included for comparison. MAIN OUTCOME MEASURE: Response of clinical symptoms. RESULTS: Presenting symptoms are highly variable. Available reports do not adequately define the natural history of the lesion. CONCLUSION: The lack of a consistent presentation despite a similar radiographic appearance suggests that the osteoma is often an incidental finding.- - - - - - - - - - ranking = 1keywords = canal (Clic here for more details about this article) |
| | Next -> |