Imaging of low- and intermediate-grade gliomas.

Imaging plays a crucial role in the diagnosis and management of low- and intermediate-grade gliomas. In this article, the traditional role of imaging studies in glioma patients and the appearance of some of the more common glial tumors on conventional computed tomography (CT) and magnetic resonance (MR) examinations are reviewed. The impact that MR spectroscopy and MR perfusion imaging have made on the evaluation patients after therapy for glial tumors also is reviewed.

Bilateral temporal hypometabolism in epilepsy.

PURPOSE: Positron emission tomography (PET) has proven useful in epilepsy surgery for its ability to identify unilateral temporal hypometabolism (UTH), which is predictive of good surgical outcome. The significance of bilateral temporal hypometabolism (BTH) is not known. METHODS: We identified all patients who had marked bilateral reduction in temporal lobe metabolism relative to the cerebellar hemispheres and compared their clinical features and treatment outcomes with those of control patients with UTH. RESULTS: BTH was evident in 10% of PET scans for epilepsy at our institution. We compared these patients with age-matched controls with UTH. The BTH patients had a higher percentage of generalized seizures; were more likely to have bilateral, diffuse or extratemporal seizure onsets; and had bilateral or diffuse magnetic resonance imaging (MRI) findings. UTH patients were more likely to have unilateral mesial temporal atrophy on MRI. Even when electrical seizure onsets were well localized, surgical outcomes were markedly worse in these patients than in controls. Medical treatment was also less successful. Social and cognitive functioning was worse in the BTH group. The only death occurred in the group with BTH. CONCLUSIONS: Patients with BTH have features distinct from those with UTH and have a worse prognosis for seizure remission after surgery.

Potential pitfalls in the work-up and diagnosis of choanal atresia.

To increase an awareness of the developmental anatomy of the nasal cavity as it applies to the radiologic work-up of choanal atresia and frontoethmoidal cephaloceles, we report two cases that demonstrate potentially serious imaging pitfalls. Two neonates with nasopharyngeal obstruction were imaged with CT and MR. Both patients had surgically proved bilateral bony choanal atresia. In addition to choanal atresia, CT showed a radiolucent, or nonossified cribriform plate and mucoid secretions within the nasal fossa, adjacent to the cribriform plate, which approximated the attenuation of brain parenchyma. In one of the patients, a preoperative diagnosis of nasopharyngeal encephalocele resulted in surgical exploration. At surgery, however, the cartilaginous cribriform plate was found to be intact.

The carotid artery: embryology, normal anatomy, and physiology.

The anatomy and physiology of the normal carotid artery serves as a starting point for understanding and evaluating existing and new methods for diagnosing carotid artery disease. This article summarizes the history and state of the art of carotid artery structure and function.

Posttraumatic epistaxis from injury to the pterygovaginal artery.

Facial and skull base trauma can cause clinically significant epistaxis. Optimal evaluation and treatment require knowledge of the pertinent vascular and skull base anatomy. We describe a patient with extensive skull base injury and epistaxis in whom CT revealed a fracture through the roof of the nasopharynx and arteriography showed injury to the pterygovaginal (pharyngeal) artery. The fracture was successfully treated with transarterial particulate embolization.

MR imaging of tibial collateral ligament injury: comparison with clinical examination.

We sought to clarify the capability of routine magnetic resonance (MR) imaging of the knee to detect and grade tibial collateral ligament (TCL) injury. We also wanted to define the exact MR findings that were the most important for diagnosis. Sixty-three patients were clinically evaluated for TCL injury prior to MR imaging of the knee on a 1.5-tesla system. MR studies were scored with respect to multiple direct and indirect findings. By discriminant analysis, the overall accuracy of classification (into clinical grades 1, 2, 3 and normal) on the basis of MR was 65%. Accuracy for detection of abnormal TCLs was 87%. The most useful MR findings for detection and grading of TCL injury were direct signs: subcutaneous edema over the TCL, focal disruption of the TCL, increased signal in the TCL on T2-weighted images, and longitudinal striations within the TCL. Indirect signs such as trabecular trauma were less useful for TCL evaluation. The presence of a tear of the anterior cruciate ligament, however, correlated with TCL injury of a higher grade. T2-weighted coronal images, by better depicting intraligamentous edema and fiber disruption, improved the MR assessment of the TCL.

Case report 707: Hemorrhagic Baker's cyst of the right calf.

A 50-year-old woman with juvenile rheumatoid arthritis presented with painful swelling of the right calf. Roentgenograms, sonograms, magnetic resonance images, and arthrograms were obtained. A diagnosis of hemorrhagic Baker's cyst was made, and surgical excision was performed. The etiology, clinical features, and radiological evaluation of simple and complicated Baker's cysts are discussed and the differential diagnosis considered.

Nonspecific findings on MR imaging. The importance of correlative studies and clinical information.

Although magnetic resonance (MR) imaging is highly sensitive for the detection of abnormalities of the musculoskeletal system, changes in marrow and soft-tissue signal intensity are often nonspecific, and benign conditions may be mistaken for malignancy. In an effort to identify the cause of this type of misdiagnosis in MR examinations, the MR scans were reviewed of 30 patients whose images manifested bone and/or soft-tissue changes that were initially believed to be consistent with malignancy but were later found to represent benign conditions. Of the 30 patients, MR abnormalities were attributable to trauma in 11, benign tumors and tumorlike conditions in ten, infection in seven, and prior radiotherapy in two. In 24 cases, correlative imaging studies (14 patients), appropriate clinical history (six patients), and/or physical and laboratory examinations (four patients) would have avoided these misdiagnoses.

Responsiveness of mouse calvaria to parathyroid hormone after explant cryopreservation: 45Ca release in vitro.

Newborn mouse calvaria prelabeled with 45Ca and cryopreserved at -196 degrees C in serum-free medium containing dimethylsulfoxide were compared to unpreserved explants for response to parathyroid hormone during subsequent culture. After short-term cryopreservation followed by rapid thawing, the viable explants continued to release 45Ca to the culture medium but additions of parathyroid hormone to the medium did not cause increased bone resorption. The data suggest that cryopreservation and thawing impairs mechanisms responsible for parathyroid hormone action on bone cells.

Migration in an economic-demographic model for the Canadian provinces.

"This paper is a description of the structure of a multiregion economic-demographic model for the Canadian provinces. An important part of the demographic model is the estimation of net migration equations based on a human capital approach and incorporating the adding-up constraint that arises since the sum of the net migration flows across all provinces must be 0 in each period. These endogenous migration flows allow for variables from the economic model (wage rates and unemployment rates) to influence the source population, the labour force and, therefore, the unemployment rate and other variables in the economic model." The model is used in simulation experiments in order to illustrate the interaction between economic and demographic factors and how this interaction affects the impact of policies.

Reassessment of inferring personality traits from Bender-Gestalt drawing styles.

Fifty patients with closure difficulty on the Bender-Gestalt and 50 patients with edging tendencies on the Bender Gestalt were assessed for possible personality traits associated with those drawing styles. Patients with and without the drawing styles were compared using MMPI data. Patients who drew along the edge of the paper showed no significant difference in MMPI scores when compared to non-edgers. Patients with closure difficulty were significantly higher on Scale O of the MMPI than were the non-closure difficulty patients. The difference was not considered to be interpretatively important.

Reply to "Validity of five MMPI alcoholism scales: a critique and reanalysis".

Replied to Hays and Stacy's critique of an article by Holmes, Dungan and McLaughlin in which the validity of MMPI alcoholism scales was questioned. Hays and Stacy asserted that the original authors misinterpreted the results of the statistical analyses. The present article presents support for the original conclusions and comments on Hays and Stacy's reanalysis.

Shock-elicited aggression as a function of early ethanol exposure.

Upon reaching maturity the offspring (N = 88) of animals exposed during pregnancy to ethanol and plain water, respectively, served as Ss in a shock-elicited aggression test. Significantly higher levels of aggression were shown by those animals that had received prenatal ethanol exposure. Several ethanol-related birth effects were also noted.

Relationship between the Luscher Color Test and the MMPI.

Administered the short form of the Luscher Color Test and the booklet form of the MMPI to 42 graduate students in a counseling program. For every S a report that described personality was written from the test results, i.e., each S had two reports, one from the Color Test and one from the MMPI. These reports were written independently by two separate examiners. Two independent raters then read the reports on each S and noted the degree of agreement between the two reports. The overall results showed very little agreement between the Color Test and the MMPI. Reasons for the poor rate of agreement are discussed.

The effects of vitamin E on zinc deficiency teratogenesis in rats.

It has been suggested that zinc deficiency may interfere with fatty acid metabolism, possibly by increasing the rate of lipid peroxidation. The hypothesis was investigated that the teratogenicity of zinc deficiency might be alleviated by vitamin E supplementation. Sprague-Dawley rats were fed during pregnancy a complete purified diet containing either 100 micrograms zinc/gram diet (control) or less than 0.4 microgram zinc/gram diet (deficient). Half of the animals in each diet group received supplemental vitamin E (200 X control). At term, fetuses were removed, examined for malformations, resorption sites were counted, and maternal and fetal tissues were analyzed for zinc concentration. Vitamin E supplementation of the control diet did not produce teratogenic effects. The number of total sites affected (resorptions + malformed fetuses) in the zinc-deficient groups was not influenced by vitamin E supplementation. Tissue zinc was significantly lower in the zinc-deficient groups, but vitamin E supplementation had no effect. These results show that vitamin E supplementation does not ameliorate the teratogenicity of zinc deficiency.

Validity of five MMPI alcoholism scales.

Assessed five alcoholism scales derived from the MMPI for their ability to classify accurately two groups of alcoholics (N = 120) and a group of nonalcoholic psychiatric patients (N = 60) in an inpatient treatment setting. The alcoholic group was divided into those who were self-committed and those who were court-committed. Depending on how the data were treated, only one, or none of the scales was accurate.