ABSTRACT
Four patients with cholesteatoma were shown to have a large area of eroded tegmen tympani on computed tomography (CT). Magnetic resonance imaging (MRI) in the coronal and sagittal plane showed temporal lobe herniation in three cases and cholesteatoma with abscess elevating the dura in one case. In the patient with a cholesteatoma and an eroded tegmen tympani on CT, MRI is indicated to rule out brain herniation into the middle ear.
Subject(s)
Cholesteatoma/diagnosis , Ear, Middle , Encephalocele/diagnosis , Magnetic Resonance Imaging , Temporal Lobe/pathology , Adult , Child , Cholesteatoma/diagnostic imaging , Diagnosis, Differential , Ear Diseases/diagnosis , Ear Diseases/diagnostic imaging , Encephalocele/diagnostic imaging , Female , Humans , Male , Middle Aged , Temporal Bone/diagnostic imaging , Temporal Bone/pathology , Temporal Lobe/diagnostic imaging , Tomography, X-Ray ComputedABSTRACT
Recurrent meningitis due to a fistula between the subarachnoid space and the middle ear or mastoid cavities has various causes, including congenital anomalies, trauma, and infection. Five cases are described in which thin-section, complex-motion tomograms showed bony abnormalities which suggested both the site and cause of the fistula. Accurate determination of the site of the fistula with this technique facilitated appropriate surgical correction in each patient. Meningitis has not recurred in any of the cases.
Subject(s)
Cerebrospinal Fluid Otorrhea/diagnostic imaging , Meningitis/etiology , Tomography, X-Ray , Aged , Cerebrospinal Fluid Otorrhea/etiology , Child , Child, Preschool , Ear, Middle/diagnostic imaging , Female , Humans , Male , Middle Aged , RecurrenceABSTRACT
The neural mechanisms for optokinetic nystagmus (OKN) may be clinically relevant to the two methods used to detect these abnormalities. If one subscribes to the cortical (macular) theory, visual fixation is always involved and results by conventional drum rotation or by pursuit of a moving light source ought to be the same. Conversely, if OKN can be the result of peripheral vision and subcortical pathways, results with the drum (which does not require macular vision) and moving light (which does) ought to be different. Both the drum and moving light methods were compared on a sample of 514 patients. Both methods compared equally in eliciting abnormal responses in patients with an established diagnosis and in correlation with calibration, gaze, and false positive responses. The drum was superior in the remainder of comparisons.
