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The acoustic startle eyeblink response (ASER) is a useful probe for investigating central nervous system activity associated with emotional responses to aversive and appetitive stimuli. Though the ASER is sensitive to change in emotional arousal, the effect of acute physical exertion on ASER has not been reported. We examined changes in ASER amplitude and latency in 26 healthy young men (24+/-5 yr) after 20 min of cycling at light and hard intensities (40% and 75% VO2peak) and after 20 min of quiet rest. Mixed model ANCOVA, controlling precondition scores, indicated no effects for ASER amplitude or latency in either sedentary or active participants (p>.10). Our findings indicate that possible effects of acute exercise on potentiated startle or ASER responses elicited by positive or negative foreground stimuli should not be expected to be confounded by an altered baseline acoustic startle eyeblink response when measured in healthy young men.

With its patients scattered throughout Central Texas--a region roughly the size of Massachusetts-Scott and White Memorial Hospital and Clinic, based in Temple, Texas, has turned to telemedicine to help bring healthcare to underserved areas. Gregory Hobbs, M.D., (left) Scott and White's director of telehealth, has overseen steady growth in the hospital's telemedicine services, which now support five clinics, five regional hospitals and five rural clinics outside of the network.

They're well on their way to becoming all-stars in the healthcare industry. All age 40 or younger, they've already accomplished much in their careers. Modern Healthcare profiles a dozen managers and executives chosen as this year's team of Up & Comers. As one observer says, "They demonstrate in significant, tangible ways the impact an individual can have on the vision, mission and quality of healthcare services."

We compared brain volumes computed by trained operators using the BRAIN-MAP algorithm, which automatically extracts the contours of the brain from gradient-echo magnetic resonance images. The images of 19 subjects randomly selected from a group of normals and a group of patients with dementia were included. BRAIN-MAP found brain perimeters that were on the average ca. 3% tighter than those obtained by two experienced operators. Between-operator and within-operator reproducibility of the analyses were also estimated and found to be (-0.13 +/- 0.51)% and (-0.63 +/- 0.08)%, respectively. Replicate volume measurement by the computer alone provided a reproducibility of (0.44 +/- 0.46)%.

We assessed reproducible definition of two standardized co-ordinate systems for intersubject analysis of brain images. The baselines in the two co-ordinate systems were a modification of the canthomeatal (mCM) line and the anterior-posterior commissural (AC-PC) line. Axial spin-echo MR images of four subjects at 1.5T were used. Operator error was computed from the replicate analyses of two operators. The mCM line was determined by the lens of the eye and the internal auditory canal, and the AC-PC line was determined by the intersection of AC and PC with the interhemispheric fissure. Reproducibility of the mCM markers (SD = 0.59 mm) did not differ significantly from that of the AC-PC line (SD = 0.68 mm). The measurement error of the angle of the baseline (delta alpha), however, was more than 7 times as large for the AC-PC line as for the mCM line. An additional error affecting the rostrocaudal rotation of the co-ordinate systems, attributable to the distance between the anatomic markers, was 2.1 and 3.6 degrees (3 mm and 5 mm slice thickness) for the mCM co-ordinate system and 8.2 and 11.0 degrees (3 mm and 5 mm slice thickness) for the AC-PC system. The AC-PC line based co-ordinate system is therefore, less reproducible than the mCM line based system. This could be improved if a combination of axial and sagittal images were used for the definition of the AC-PC line.

Objective: The goal of the study was to examine the volume of selected brain regions in a group of mildly impaired patients with Alzheimer's disease (AD). Five regions were selected for analysis, all of which have been reported to show substantial change in the majority of patients with AD at some time in the course of disease., Design: Case-control study with the experimenter "blinded.", Setting: Hospital-based magnetic resonance imaging center., Participants: Fifteen subjects, eight patients with the diagnosis of probable dementia of the Alzheimer type made in concordance with National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association criteria and seven age-matched healthy control subjects., Results: Three of the volumetric measures were significantly different between patients with AD and controls: the hippocampus, the temporal horn of the lateral ventricles, and the temporal lobe. Two of the measures did not significantly differentiate patients with AD and controls: the amygdala and the basal forebrain. A discriminant function analysis demonstrated that a linear combination of the volumes of the hippocampus and the temporal horn of the lateral ventricles differentiated 100% of the patients and controls from one another., Conclusions: The results suggest that the hippocampus and the temporal horn of the lateral ventricles may be useful as antemortem markers of AD in mildly impaired patients.

We have implemented a computerized system for relatively rapid (< 1 h) three-dimensional (3D) surface rendering of flow-sensitive (gradient refocused) magnetic resonance images. The method has been applied in 8 patients with six different clinical problems and was found to enhance understanding of normal and abnormal aortic, caval, and portosystemic venous anatomy. 3D images are useful for communicating complex anatomic information and may help with difficult diagnoses. Advantages and limitations of the present system are discussed.

Ten patients with Alzheimer's disease underwent computed tomography and magnetic resonance imaging at the same point in time. The mean Mini-Mental State examination score of the patients was 23, indicating that they were mildly impaired. Ten age-equivalent controls also obtained computed tomographic and magnetic resonance imaging scans. A semiautomated computer program analyzed nine comparable regions of interest on each set of scans. When regions of interest from both types of scans were combined in the same discriminant function analysis, the first two variables selected were from the magnetic resonance imaging data set, and they significantly differentiated 95% of the patients and controls.

Earlier studies have concluded that exercise tolerance during graded stress testing is overestimated in males showing the Type A Behavior Pattern (TABP) because of high motivation and suppressed ratings of perceived exertion (RPE). However, the studies used the Jenkins Activity Survey (JAS) to assess TABP and employed exercise protocols that were unstandardized or uninterpretable for clinical prescription. Because the JAS lacks validity for predicting the criterion Structured Interview (SI) for TABP, the usefulness of concurrent self-report estimates of TABP for predicting RPE during standard exercise testing warrants additional study. During clinical treadmill testing of 86 asymptomatic Caucasian men (45 +/- 9 yr), we examined three standard estimates of TABP (JAS, Bortner, Framingham) as predictors of: 1) the covariance (RPE') of RPE (Borg Category Scale) with VO2 (ml.kg-1.min-1) during 5 min of graded walking (5.47 km.h-1, 2.25%.min-1); 2) VO2 and RPE (11.6 +/- 2.2) at a preferred level of exertion (approximately 65% +/- 10% VO2PEAK); 3) VO2PEAK and RPE at VO2PEAK. Multiple linear regression analyses found no relations (P greater than 0.10) between estimates of TABP and treadmill responses. Discriminant analyses of Type A and Type B groups formed from tertiles consistent with population norms showed no differences (P greater than 0.01) for RPE of treadmill performance. Our findings question prior reports of RPE suppression associated with TABP estimates. We conclude that practically implementable estimates of TABP do not offer useful information for clinical predictions of RPE, preferred exertion level, or VO2PEAK in asymptomatic middle-aged Caucasian men.

As an initial approach to computer-automated segmentation of cerebral spinal fluid (CSF) vs. brain parenchyma in MR scans, and the transformation of these data sets into volumetric information and 3D display, we examined the ventricular system in a sample of ten chronic schizophrenics with primarily positive symptoms and 12 normal subjects. While no significant differences were noted between groups on volumetric measures of ventricular brain ratio or lateral ventricle size, normals showed a pattern of left greater than right lateral ventricular volume asymmetry not present in the schizophrenics. Within the schizophrenic group, departure from the normal left greater than right pattern was highly correlated with thought disorder.