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W W Lo

Publications and source records attributed to W W Lo.

46 records · Page 3Linked to original sources
PubMed1984

Gas-CT cisternography for detection of small acoustic nerve tumors.

Gas-CT cisternography is a simple and accurate procedure for detection of small acoustic nerve tumors. Review of one of the largest series in a single institution found that 98% of the studies clearly showed the presence or absence of tumors. The diagnostic pitfalls of the small number of studies in which significant errors were made, or could have been made, are discussed. It is concluded that certain situations appear to call for extra caution: (a) when the filling defect does not show a convex surface, (b) when the amount of cisternal gas is marginal, and (c) when the canal is small. In such situations careful attention to details and healthy skepticism may avert potential errors.

Adolescent↗
PubMed1984

High-resolution CT in the evaluation of glomus tumors of the temporal bone.

High-resolution computed tomography (HRCT) was performed in 33 cases of glomus tumors of the temporal bone and 10 cases of other tumors in and around the jugular foramen. HRCT helped to differentiate glomus tumors from vascular anomalies and from other benign or malignant lesions, and to determine the extent of deep involvement. It provided essential information for planning the surgical approach. When a lesion is large or appears atypical, complementary angiography is helpful. Otherwise, angiography may not be necessary.

Ear Neoplasms↗
PubMed1984

High-resolution CT of the jugular foramen: anatomy and vascular variants and anomalies.

In high-resolution computed tomographic (HRCT) images of dry skulls and patients, the anatomy of the jugular foramen and its neighboring structures was demonstrated to excellent advantage. Among those structures visualized were the cortical margins of the jugular compartments, which are important in evaluating tumor involvement, the anatomic relationship between the jugular fossa and the hypotympanum, and the adjacent basal foramina. The inferior tympanic canaliculus, which transmits the inferior tympanic artery and nerve and houses one fifth of the glomus formation, thereby playing a role in arterial anomalies as well as glomus tumors, was occasionally recognizable. In addition, subtle bone findings associated with vascular anomalies in and around the jugular foramen, critically important in the differential diagnosis of glomus tumors, were visualized. Examples of these findings are presented.

Ear Neoplasms↗
PubMed1984

Cholesterol granuloma of the petrous apex: CT diagnosis.

Cholesterol granuloma of the petrous apex is a readily recognizable and treatable entity that is more common than previously realized. Cholesterol granuloma grows slowly in the petrous apex as a mass lesion until it produces hearing loss, tinnitus, vertigo, and facial twitching. Twelve cases of cholesterol granuloma of the petrous apex are illustrated; ten of these are analyzed in detail, especially with respect to CT findings. A sharply and smoothly marginated expansile lesion in the petrous apex, isodense with brain and nonenhancing on CT, is in all probability a cholesterol granuloma. Cholesterol granuloma and cholesteatoma of the petrous apex are different lesions and treated differently. Cholesterol granuloma can be treated simply and effectively by drainage and permanent fistulization. Preoperative recognition by CT is important for planning proper treatment.

Adult↗
PubMedDate not supplied

Angiotensin II stimulates inositol phosphate formation in rat anterior pituitary glands.

The effect of angiotensin II (AII) on polyphosphoinositide (PPI) turnover at the pituitary was studied. When [3H]inositol-prelabelled rat anterior hemipituitaries were incubated with AII (10 microM) for 30 min in the presence of Li+ (10 mM), the production of IP, IP2 and IP3 were increased to 182, 199 and 158% of paired control values. Time course studies showed that the stimulation of IP3 formation by AII was significant after 2 min incubation and preceded the accumulation of the other inositol phosphates. The specificity of the AII effect was confirmed by inhibition with the specific AII antagonist, saralasin. These findings suggest that AII action at the anterior pituitary can be mediated via the early hydrolysis of PPI.

Angiotensin II↗
PubMedDate not supplied

The anterior epitympanic recess: CT anatomy and pathology.

PURPOSE: To describe the variation in size and shape of the anterior epitympanic recess and to discuss pathologic processes that affect this space. METHODS: Axial CT scans of the temporal bones of 31 adults and 19 children were reviewed retrospectively to ascertain the morphology and size of the anterior epitympanic recess. Selected confirmed disease processes involving this space were studied. RESULTS: The anterior epitympanic recess, which is consistently identified on axial CT scans, is either single or multicelled. In our study, it was made up of a solitary cell in 61 of 100 ears. Side-to-side symmetry in shape was present in 78 of 100 cases. The size of a solitary air cell ranged from 1.0 to 7.0 mm. CONCLUSIONS: The configuration of the anterior epitympanic recess is readily affected by a persistent stapedial artery, by facial nerve schwannomas, by hemangiomas of the facial nerve canal in the geniculate region, and by congenital and acquired cholesteatomas. Familiarity with the CT anatomy of this space facilitates recognition of these pathologic processes at an early stage.

Adolescent↗