Attempted suicide and suicide in functional psychoses.

A total of 2,243 first admissions to Gaustad Hospital between 1938 and 1961 diagnosed as functional psychotics were either followed up to the time of their death within 5 years, or observed over a period of 5 years, and then reexamined. Of these patients, 325 had attempted suicide prior to their admission. The frequency of attempted suicide was equal in both sexes. Men appeared to use more dangerous methods, and to have more serious intentions. The psychosis appears to have been of importance when considering whether, but not how the suicide should be attempted. The greatest risk of attempted suicide was to be found amongst patients with psychoses of a depressive nature. Twenty-eight of the 2,243 patients in this study committed suicide within 5 years following their discharge, and a further 20 took their own lives prior to the reexamination. A certain connection can be seen between attempted suicide and psychotic symptoms.     

Modified functional neck dissection: a useful technique for oral cancers

Among 60 patients with oral squamous cell carcinoma, 30 were treated by the modified functional neck dissection (preserve 8 functional tissues), 30 were treated by functional neck dissection (preserve 3 functional tissues). The recurrent rate of cervical lymph node and the sense of skin were assessed. The recurrence rates in cervical nodes was 6.67% and 10%, respectively (p > 0.05) in patients who accepted modified functional neck dissection and functional neck dissection. The sensation in skin in patients who accepted modified functional neck dissection was better than those who accepted functional neck dissection (p < 0.01). Modified functional neck dissection is helpful to decrease postoperative complications, without increasing recurrent rates of cervical lymph node.     

Functional observational battery and motor activity in rats after single administration of two NHE 1 inhibitors

Two tests, a functional observational battery (FOB) and measurement of motor activity, have been used to screen the two NHE inhibitors EMD 96785 and EMD 125021 for neurobehavioral effects. These two NHE inhibitors, which exhibit a marked selectivity for the NHE 1 isoform, are under development in the research laboratories of Merck KGaA. NHE inhibitors are developed for the treatment of acute myocardial infarction and chronic heart failure. In prior studies with EMD 96785 and EMD 125021, clinical symptoms, such as uncoordinated movements and weakness of the hindlimbs, were detected in rats. The aim of this study was the evaluation of clinical findings in more detail using a FOB and measurement of motor activity in 96 female rats. The time course and reversibility of the adverse effects were investigated. The animals were treated with EMD 96785 or EMD 125021 by intravenous injection at a single dose of 100 mg/kg and four different time points (2 h, 1 day, 7 days and 21 days after treatment) were chosen for the clinical examination. This neurobehavioral test battery clearly detected neurological activity and defined time-course characteristics after treatment with EMD 96785 or EMD 125021. The various clinical parameters were grouped into functional-related domains and most alterations were seen in the domains of central nervous system and neuromuscular system. The most prominent clinical findings were seen with the pharmacologically more potent NHE inhibitor EMD 125021 when compared to EMD 96785. The clinical symptoms were proven to be reversible by 7 days after the single treatment for both compounds.     

Careful use of pseudo R-squared measures in epidemiological studies

Many epidemiological research problems deal with large numbers of exposed subjects of whom only a small number actually suffers the adverse event of interest. Such rare events data can be analysed by employing an approximate Poisson model. The objective of this study is to challenge the interpretability of the corresponding Poisson pseudo R-squared measure. It will lack sensible interpretation whenever the approximate Poisson outcome is generated by counting the number of events within covariate patterns formed by cross-tabulating categorical covariates. The failure is caused by the immanent arbitrariness in the definition of the covariate patterns, that is, independent Bernoulli events, B(1,pi), are arbitrarily combined into binomially distributed ones, B(n,pi), which are then approximated by the Poisson model.     

From anatomic standardization analysis of perfusion SPECT data to perfusion pattern modeling: evidence of functional networks in healthy subjects and temporal lobe epilepsy patients

RATIONALE AND OBJECTIVES: In the general context of perfusion pattern modeling from single-photon emission computed tomographic (SPECT) data, the purpose of this study is to characterize interindividual functional variability and functional connectivity between anatomic structures in a set of SPECT data acquired from a homogeneous population of subjects. MATERIALS AND METHODS: From volume of interest (VOI)-perfusion measurements performed on anatomically standardized SPECT data, we proposed to use correspondence analysis (CA) and hierarchical clustering (HC) to explore the structure of statistical dependencies among these measurements. The method was applied to study the perfusion pattern in two populations of subjects; namely, SPECT data from 27 healthy subjects and ictal SPECT data from 10 patients with mesio-temporal lobe epilepsy (MTLE). RESULTS: For healthy subjects, anatomic structures showing statistically dependent perfusion patterns were classified into four groups; namely, temporomesial structures, internal structures, posterior structures, and remaining cortex. For patients with MTLE, they were classified as temporomesial structures, surrounding temporal structures, internal structures, and remaining cortex. Anatomic structures of each group showed similar perfusion behavior so that they may be functionally connected and may belong to the same network. Our main result is that the temporal pole and lenticular nucleus seemed to be highly relevant to characterize ictal perfusion in patients with MTLE. This exploratory analysis suggests that a network involving temporal structures, lenticular nucleus, brainstem, and cerebellum seems to be involved during MTLE seizures. CONCLUSION: CA followed by HC is a promising approach to explore brain perfusion patterns from SPECT VOI measurements.     

Comparing 0.2 tesla with 1.5 tesla intraoperative magnetic resonance imaging analysis of setup, workflow, and efficiency

RATIONALE AND OBJECTIVES: To compare low-field with high-field intraoperative magnetic resonance imaging (MRI) in respect to setup, workflow, and efficiency. MATERIALS AND METHODS: A total of 750 patients were investigated either with a 0.2 T (March 1996-July 2001) or a 1.5 T (April 2002-August 2004) MRI system adapted for intraoperative use. RESULTS: With the low-field setup, 330 patients were examined in 65 months; with the high-field setup, 420 patients were examined in 29 months, which is a 2.8-fold increase in cases per month (14.5 versus 5.1) reflecting improved ease of use. Concerning intraoperative workflow, the time for preparation to start intraoperative imaging decreased fivefold (2 minutes instead of 10 minutes); navigation was applied more often with 57% versus 51% (240/420 versus 167/330), whereas functional data were integrated in 35% versus 39% (84/240 versus 65/167). Application of navigation updates was doubled (22% versus 11%; 53/240 versus 18/167). Image acquisition time was reduced by a factor of two, allowing a more detailed imaging protocol, whereas the image quality is clearly improved in the high-field setup, where there was no difference between the standard preoperative image quality compared with the intraoperative quality. This contributed to an increased detection of tumor remnants and extended resections in pituitary (36% versus 29%; 47/129 versus 17/59) and glioma surgery (41% versus 26%; 38/93 versus 28/106). CONCLUSION: Compared with the low-field setup, the high-field setup results not only in clearly superior image quality and increased imaging armamentarium, contributing to increased rates of detected tumor remnants, but also in a distinct improvement of intraoperative workflow. Furthermore, intraoperative high-field MRI offers various modalities beyond standard anatomic imaging, such as magnetic resonance spectroscopy, diffusion tensor imaging, and functional MRI.     

Magnetic field strength increase yields significantly greater contrast-to-noise ratio increase: Measured using BOLD contrast in the primary visual area

RATIONALE AND OBJECTIVE: The advantage of a higher static magnetic field for functional MRI has been advocated; however, the observed advantage varies. The aim of this study was to evaluate the effect of increasing static magnetic field strength on the task-related increase in blood oxygenation level-dependent (BOLD) signal and residual noise with visual stimuli of different frequencies, which may enable better comparisons of results of different MRI scanners. MATERIALS AND METHODS: Eight right-handed healthy volunteers were presented checkerboard stimuli flickering at 5 different frequencies up to 8 Hz. Field strengths of 3 T or 1.5 T were used to measure frequency-dependent signal changes in the primary visual area. Regression analysis was performed for the signal increase and the "noise," which was defined by the root mean of squares of the residual signal fluctuation. These values were compared and their relationship was analyzed. Imaging parameters were identical except for the use of a 25% shorter echo time using 3 T. RESULTS: The frequency-dependent increase in BOLD signal using 3 T was twice that using 1.5 T. In contrast, the ratio of noise values that reflect time-course signal fluctuation (3 T/1.5 T) was only 0.88. There was large individual variance in these values, but the slope and noise values were linearly related using either field strength. The contrast-to-noise ratio using 3 T was 2.3 times higher than that using 1.5 T. CONCLUSION: There was a greater-than-linear increase in the contrast-to-noise ratio compared with the increase of field strength, demonstrating an advantage of using higher field strengths in fMRI studies.     

Neural correlates of telling lies: a functional magnetic resonance imaging study at 4 Tesla

RATIONALE AND OBJECTIVE: Intentional deception (ie, lying) is a complex cognitive act, with important legal, moral, political, and economic implications. Prior studies have identified activation of discrete anterior frontal regions, such as the ventrolateral prefrontal cortex (VLPFC), dorsolateral prefrontal cortex (DLPFC), dorsal medial prefrontal cortex (DMPFC), and anterior cingulate cortex (ACC) during deception. To extend these findings, we used novel real-time functional magnetic resonance imaging (fMRI) technology to simulate a polygraph experience in order to evoke performance anxiety about generating lies, and sought to ascertain the neural correlates of deception. MATERIALS AND METHODS: In this investigational fMRI study done with a 4-T scanner, we examined the neural correlates of lying in 14 healthy adult volunteers while they performed a modified card version of the Guilty Knowledge Test (GKT), with the understanding that their brain activity was being monitored in real time by the investigators conducting the study. The volunteers were instructed to attempt to generate Lies that would not evoke changes in their brain activity, and were told that their performance and brain responses were being closely monitored. RESULTS: Subjects reported performance anxiety during the task. Deceptive responses were specifically associated with activation of the VLPFC, DLPFC, DMPFC, and superior temporal sulcus. DISCUSSION: These findings suggest the involvement of discrete regions of the frontal cortex during lying, and that the neural substrates responsible for cognitive control of behavior may also be engaged during deception.     

Time course of functional recovery after coronary artery bypass grafting surgery according to the preoperative reversibility of perfusion impairment on myocardial SPECT

Purpose Ischaemic myocardial dysfunction shows different time courses of functional recovery according to the pathophysiological characteristics of the dysfunction. In this study, we investigated the time course of functional recovery according to the preoperative reversibility of perfusion impairment on myocardial single-photon emission computed tomography (SPECT) after revascularisation surgery.Methods Forty-eight patients (42 men and 6 women; mean age 59±9 years) who underwent revascularisation surgery were included in the study. ²⁰¹Tl rest/dipyridamole stress ^99mTc-sestamibi gated SPECT was performed 10±8 days before (preoperative), 105±13 days after (early follow-up) and 497±66 days after (late follow-up) surgery. Using a 20-segment model, segmental perfusion and thickening were quantified with automatic software. As an indicator of the reversibility of perfusion impairment, a reversibility score (RevS) was defined as a measure of rest minus stress perfusion values. Segmental dysfunction and functional recovery were defined from quantified thickening values. Function-recovered segments were divided into early recovery and late recovery groups, and preoperative perfusion status was compared in these groups. Function-recovered segments were also re-classified into high-RevS and low-RevS groups according to the preoperative RevS, and the time courses of functional recovery were investigated in each group.Results A total of 502 segments were included in the analysis and 263 were finally classified as function-recovered segments. Of these, 172 were in the early recovery and 91 in the late recovery group. In terms of preoperative perfusion status, RevS was 8.9±10.8 in the early recovery group and 5.4±11.0 in the late recovery group (P=0.01). When all 502 segments were classified by RevS, no difference in the proportion of final function recovery was observed between the high-RevS and the low-RevS group (54% vs 51%). However, the proportion of early recovery was higher in the high-RevS group (73%) than in the low-RevS group (57%) (P=0.01).Conclusion Ischaemic dysfunctional myocardium with reversible perfusion impairment tends to recover function earlier after revascularisation surgery than myocardium with a persistent decrease in perfusion.