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George W. Christison

Loma Linda University

Publishes on Functional Brain Connectivity Studies, Cardiac Imaging and Diagnostics, Advanced Neuroimaging Techniques and Applications. 18 papers and 2.1k citations.

18Publications
2.1kTotal Citations

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Top publicationsby citations

Anatomical Abnormalities in the Brains of Monozygotic Twins Discordant for Schizophrenia
Richard L. Suddath, George W. Christison, E. Fuller Torrey et al.|New England Journal of Medicine|1990
Cited by 1kOpen Access

Recent neuroradiologic and neuropathological studies indicate that at least some patients with schizophrenia have slightly enlarged cerebral ventricles and subtle anatomical abnormalities in the region of the anterior hippocampus. Using magnetic resonance imaging (MRI), we studied 15 sets of monozygotic twins who were discordant for schizophrenia (age range, 25 to 44 years; 8 male and 7 female pairs). For each pair of twins, T1-weighted contiguous coronal sections (5 mm thick) were compared blindly, and quantitative measurements of brain structures were made with a computerized image-analysis system. In 12 of the 15 discordant pairs, the twin with schizophrenia was identified by visual inspection of cerebrospinal fluid spaces. In two pairs no difference could be discerned visually, and in one the twin with schizophrenia was misidentified. Quantitative analysis of sections through the level of the pes hippocampi showed the hippocampus to be smaller on the left in 14 of the 15 affected twins, as compared with their normal twins, and smaller on the right in 13 affected twins (both P less than 0.001). In the twins with schizophrenia, as compared with their normal twins, the lateral ventricles were larger on the left in 14 (P less than 0.003) and on the right in 13 (P less than 0.001). The third ventricle also was larger in 13 of the twins with schizophrenia (P less than 0.001). None of these differences were found in seven sets of monozygotic twins without schizophrenia who were studied similarly as controls. We conclude that subtle abnormalities of cerebral anatomy (namely, small anterior hippocampi and enlarged lateral and third ventricles) are consistent neuropathologic features of schizophrenia and that their cause is at least in part not genetic. Further study is required to determine whether these changes are primary or secondary to the disease.

Evaluation of R wave amplitude changes versus ST-segment depression in stress testing.
Cited by 184Open Access

Exercise ECGs and coronary angiograms were reviewed in 266 patients (81 normals and 185 with significant coronary artery disease). Thirty-three false positive and 96 false negative ST responses to stress testing were purposely chosen to determine if the R wave could reduce the number of false ST responses. R wave amplitude changes were measured in the control and in the immediate postexercise period. An increase or no change in R wave was taken as evidence of an abnormal response, while a decrease in the R wave was a normal response. The sensitivity by ST segment was 48% and the specificity was 59%. These values were low because of the large number of false positive and negative ST responses in the study. It was our purpose to determine if these lowered values could be significantly improved by the R wave. Using R wave criteria, the sensitivity was 63% (P is less than 0.01) while the specificity was 79% (P is less than 0.01). The sensitivity and specificity of stress testing can be significantly improved using R wave changes.

A Quantitative Investigation of Hippocampal Pyramidal Cell Size, Shape, and Variability of Orientation in Schizophrenia
George W. Christison|Archives of General Psychiatry|1989
Cited by 178

Hippocampal abnormalities have been described in patients with schizophrenia, with disarray of pyramidal cells being one of the more intriguing findings. Controversy exists regarding whether disarray is present in the brains from schizophrenics in the Yakovlev collection at the Armed Forces Institute of Pathology, Washington, DC. We examined for disarray the CA1 region of the midhippocampus of 17 schizophrenics and 32 controls from this collection using computerized determination of neuronal angle and directional statistical analysis of the variability of neuronal angle. Neuronal area and shape were also assessed. We found no differences between patients and controls in these measures. Possible methodological reasons for the discrepancy between our and others' findings are discussed, as well as directions for further research into possible pathological study of the hippocampus and related structures in schizophrenia.

When Symptoms Persist: Choosing Among Alternative Somatic Treatments for Schizophrenia
Cited by 178Open Access

Many patients with schizophrenia continue to have significant disabling symptoms despite adequate trials of different types and doses of traditional neuroleptics. Clinicians treating these neuroleptic-resistant patients must look to other treatments in the hope of providing some relief. The literature on many of the alternative treatments is too scanty for firm conclusions. We offer criteria for deciding which treatments may warrant consideration. We review the evidence for the eight treatments we found to meet these criteria and discuss clinical points salient to their use in this population. Although not always conclusive, the data do offer clues for treatment guidelines and an approach to choosing among the available treatments is suggested.

The Medical Condition Regard Scale
Cited by 167

PURPOSE: To develop a non-condition-specific scale to capture biases, emotions, and expectations generated by medical condition descriptors. METHOD: An 18-item pilot scale was developed from the literature on physicians' responses to patients they like and dislike, stigma definitions, and discussions with primary care faculty. Exploratory factor analysis was conducted after 440 medical students rated one of 12 diverse conditions. Confirmatory factor analysis was performed after 163 medical students rated two psychiatric conditions. Validity was evaluated by the scale's ability to meaningfully stratify the 12 conditions and identify changes in attitudes toward psychiatric conditions after a psychiatry clerkship. RESULTS: Exploratory factor analysis supported an 11-item unidimensional solution (all factor loadings >.40, coefficient alpha =.87). The final scale, the Medical Condition Regard Scale (MCRS), taps the degree to which medical students find patients with a given medical condition to be enjoyable, treatable, and worthy of medical resources. The unidimensional model also was supported by the confirmatory factor analyses for the two psychiatric conditions (both comparative fit indices =.98). The scale stratified the 12 conditions as expected: straightforward medical conditions rated highest, somatoform conditions rated lowest. Students showed greater regard for patients with major depression after the psychiatry clerkship, and students who rotated through an addiction treatment program showed a greater increase in regard for patients with alcoholism than did students not exposed to addiction treatment. CONCLUSION: MCRS scores are reliable, and the scale appears to be a valid instrument for assessing regard for any medical condition.