1/14. 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 = 1keywords = canal (Clic here for more details about this article) |
2/14. 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 = 0.5keywords = canal (Clic here for more details about this article) |
3/14. The pathology of the temporal bones of a child with acquired cytomegalovirus infection: studies by light microscopy, immunohistochemistry and polymerase-chain reaction.STUDY DESIGN: The first case of an acquired cytomegalovirus (CMV) infection of the inner ear is reported in a 3-year-old girl in remission from acute lymphocytic leukemia. methods: Horizontal sections of the temporal bones were studied by light microscopy and immunohistological staining by avidin-biotin-complex-technique was performed on selected archival sections. Three sections were processed for detection of the virus genome by the polymerase chain reaction (PCR). RESULTS: By light microscopy the epithelium of the endolymphatic sac, the utricle and the semicircular canals showed deeply stained acidophilic inclusions and the stria vascularis had a loose structure especially in the intermediate layer. The changes were limited to the non-sensory parts of the labyrinth and no CMV type cells were observed in the organ of corti. There was a loss of inner and outer hair cells and loss of cochlear ganglion cells caused by either the virus or treatment with gentamicin. Standard immunohistochemistry failed to demonstrate staining with CMV antibodies, but PCR, demonstrated CMV-dna in one section. CONCLUSION: Molecular techniques may be able to detect acquired CMV infections in archival pediatric bones temporal bones. The histologic findings in the labyrinth were milder, however showed some similarity to children with congenital CMV labyrinthitis.- - - - - - - - - - ranking = 0.5keywords = canal (Clic here for more details about this article) |
4/14. Multichannel cochlear implant and electrically evoked auditory brainstem responses in a child with labyrinthitis ossificans.Ossification of the cochlea following meningitis presents a surgical challenge. Electrode mapping, especially in the young child, is difficult given the uncertainty of electrode contact with viable neural elements. This paper reviews surgical technique and the use of auditory brainstem responses to map the electrodes. A 4-year-old child deafened by meningitis at age 20 months had bilateral cochlear ossification by computed tomography. At surgery, a canal wall-down mastoidectomy and closure of the ear canal were performed. A trough around the modiolus was drilled, and the electrode array was placed in it. Post-operatively, the patient gave aversive or no responses to electrode stimulation. To assess electrode function, auditory brainstem responses to individual electrode activation were obtained under general anesthesia. Functioning electrodes could thus be selected for mapping. The patient now responds well to sound.- - - - - - - - - - ranking = 1keywords = canal (Clic here for more details about this article) |
5/14. Contrast enhancement of the labyrinth on MR scans in patients with sudden hearing loss and vertigo: evidence of labyrinthine disease.The sudden onset of hearing loss and vertigo presents a difficult diagnostic problem. We describe the finding of labyrinthine enhancement on MR images in five patients with sudden unilateral hearing loss or vertigo or both and correlate the MR findings with audiologic and electronystagmographic studies. All patients were studied with T2-weighted axial images through the whole brain, contrast-enhanced 3-mm axial T1-weighted images through the temporal bone, and enhanced T1-weighted sagittal images through the whole brain. Cochlear enhancement, on the side of hearing loss only, was found in all five patients. The presence of associated vestibular enhancement correlates with objective measures of vestibular function on the electronystagmogram. In two patients, the resolution of symptoms 4-6 months later correlated with resolution of the enhancement on gadopentetate dimeglumine-enhanced MR images. Two patients had luetic labyrinthitis. No labyrinthine enhancement was seen in a series of 30 control subjects studied with gadopentetate dimeglumine-enhanced MR using the same protocol. Labyrinthine enhancement in patients with auditory and vestibular symptoms is a new finding and is indicative of labyrinthine disease. While abnormalities on electronystagmograms and audiograms are nonspecific and indicate only a sensorineural problem, gadopentetate dimeglumine-enhanced MR may separate patients with retrocochlear lesions, such as acoustic neuromas, from those in whom the abnormal process is in the labyrinth or is intraaxial. This group of patients underscores the importance of identifying and commenting on the structures of the membranous labyrinth when evaluating MR studies of the internal auditory canal and the cerebellopontine angle in individuals with hearing loss.- - - - - - - - - - ranking = 0.5keywords = canal (Clic here for more details about this article) |
6/14. Histopathological features of the spiral ganglion and cochlear nerve in temporal bones from three patients with profound hearing loss.In the following study the condition of the spiral ganglion and the cochlear nerve of ears from patients suffering from profound hearing loss is described. The number of spiral ganglion cells has been related to the clinical diagnosis. The number of spiral ganglion cells in the two temporal bones of a patient with neomycin ototoxicity was almost normal. A reduction of less than one-third of spiral ganglion cells has been observed in the temporal bones of a child who died after a bacterial labyrinthitis. The temporal bone with a Mondini dysplasia revealed a pronounced reduction of ganglion cells of more than two-thirds. The cochlear nerve trunk in the internal auditory canal appeared normal in all three cases. The present findings are discussed in respect to the degenerative behaviour of the cochlear neural elements in human being compared to animals.- - - - - - - - - - ranking = 0.5keywords = canal (Clic here for more details about this article) |
7/14. Pseudomonas labyrinthitis.pseudomonas aeruginosa is the gram-negative bacterial rod which is often isolated from chronic aural discharge. This microorganism may also cause necrotizing infection of the external auditory canal in certain patients with impaired host-defense mechanisms. Involvement of the inner ear by this microbe is extremely rare. In this communication, we report a case of pseudomonas labyrinthitis which resulted from traumatic middle ear injury. infection produced massive granulations and extensive bone destruction of the otic capsule. This case shows that while P.aeruginosa is usually an avirulent opportunistic pathogen, it may also cause a highly destructive labyrinthitis if the inner ear is entered.- - - - - - - - - - ranking = 0.5keywords = canal (Clic here for more details about this article) |
8/14. Mycotic infection of the temporal bone.Herein is a histopathologic study of the temporal bone changes in three patients with fatal systemic fungal infections. All three patients were compromised hosts who failed to respond to adequate chemotherapy. Interestingly, one patient with cryptococcosis had a unilateral hearing loss as the sole manifestation of cerebral cryptococcosis. The most common histopathologic change consisted of a fungal infiltration of the nerves in the internal auditory canal, with moderate infiltration of the sense organs of the membranous labyrinth.- - - - - - - - - - ranking = 0.5keywords = canal (Clic here for more details about this article) |
9/14. Viral labyrinthitis: early pathology in the human.The histologic findings in the temporal bones of three patients who died from viral encephalopathy are presented. pathology was restricted to the scala media, vestibular labyrinth, and internal auditory canal and was considered to be expressions of viral labyrinthitis. The changes were different degrees of degeneration of the organ of corti, early encapsulation of the tectorial membrane, degeneration of the stria vascularis, and round cell infiltration of the modiolus and contents of the internal auditory canal. A new finding in the organ of corti and early stages of cystic degeneration of the stria vascularis are documented. In all cases, the saccule was degenerated with sloughing of the otolithic membrane and vestibular labyrinth was involved in varying degrees.- - - - - - - - - - ranking = 1keywords = canal (Clic here for more details about this article) |
10/14. pathology of congenital syphilitic labyrinthitis.An alarming increase in the incidence of syphilitic labyrinthitis has prompted us to review the pathology of this condition. The temporal bones of two patients with congenital syphilis of the ear were studied histopathologically. They showed diffuse osteitic changes in the otic capsule associated with severe hydrops and degeneration of the membranous labyrinth. The posterosuperior wall of the external auditory canal as well as the auditory ossicles showed numerous connective tissue filled spaces surrounded by thin bony trabeculae. These lesions probably represent healed luetic osteitis. There was severe degeneration of the sensorineural structures in the cochlea. A finding of particular interest was the infiltration and fibrous obliteration of the ductus endolymphaticus in both cases. The significance of these findings in relation to the pathophysiology and treatment of syphilitic labyrinthitis is emphasized.- - - - - - - - - - ranking = 0.5keywords = canal (Clic here for more details about this article) |
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