Quantitative ultrasound of the phalanges and DXA of the lumbar spine and proximal femur in evaluating the risk of osteoporotic vertebral fracture in postmenopausal women

Purpose

This study was undertaken to compare the quantitative ultrasound (QUS) parameters of amplitudedependent speed of sound (AD-SoS) and ultrasound bone profile index (UBPI) of the phalanges with bone mineral density (BMD) of the lumbar spine and proximal hip using dual-energy X-ray absorptiometry (DXA) in discriminating women with vertebral fracture.

Materials and methods

A total of 692 postmenopausal Caucasian women were included in the study. The presence of vertebral fracture was evaluated by radiography. AD-SoS and UBPI were measured at the phalangeal metaphysis using a DBM Sonic device. Multiple logistic regression analysis was performed to estimate the odds ratio (OR) for vertebral fractures. The ORs were also adjusted for the significant anthropometric variables of age, weight and height. Furthermore, for QUS parameters, the ORs were also adjusted for lumbar spine and total hip BMD.

Results

All measurements obtained with DXA and QUS significantly discriminated between women with and without fractures (p<0.0001). However, the OR was higher for lumbar spine BMD (OR 4.01), AD-SoS (OR 3.81), total hip (OR 3.7) and femoral neck BMD (OR 3.62).

Conclusions

The QUS parameter AD-SoS showed diagnostic sensitivity equal to that of lumbar DXA in discriminating between women with and without osteoporotic vertebral fractures.     

Advancing the Neurophysiological Understanding of Delirium

Delirium is a common problem associated with substantial morbidity and increased mortality. However, the brain dysfunction that leads some individuals to develop delirium in response to stressors is unclear. In this article, we briefly review the neurophysiologic literature characterizing the changes in brain function that occur in delirium, and in other cognitive disorders such as Alzheimer's disease. Based on this literature, we propose a conceptual model for delirium. We propose that delirium results from a breakdown of brain function in individuals with impairments in brain connectivity and brain plasticity exposed to a stressor. The validity of this conceptual model can be tested using Transcranial Magnetic Stimulation in combination with Electroencephalography, and, if accurate, could lead to the development of biomarkers for delirium risk in individual patients. This model could also be used to guide interventions to decrease the risk of cerebral dysfunction in patients preoperatively, and facilitate recovery in patients during or after an episode of delirium.     

Interactive Effects of Traumatic Brain Injury and Anxiety Sensitivity Cognitive Concerns on Post-traumatic Stress Among Active Duty Soldiers

Traumatic brain injury (TBI) history has been repeatedly linked with heightened risk for post-traumatic stress (PTS) among active duty soldiers. Yet, no research to date has examined the relationship between TBI and PTS in the context of anxiety sensitivity cognitive concerns (ASCC), a well-established cognitive-affective risk factor for PTS that may intensify the effects of TBI on PTS via the amplification of TBI-related symptoms of cognitive dyscontrol. The present study tested the moderating effects of ASCC on the relationship between the number of lifetime probable TBIs and PTS among a sample of 89 trauma-exposed active duty soldiers. Results demonstrated that high ASCC potentiated the relationship between number of probable TBIs and PTS while low ASCC muted this association. Interestingly, ASCC was more closely related to PTS among those with a greater number of probable TBIs compared to those with zero past TBIs. These results underscore the importance of ASCC in the association of TBI and PTS.     

Challenges in using rater judgements in medical education

Changes in the healthcare environment are putting increasing pressure on medical schools to make faculty accountable and to document the quality of the medical education they provide. Faculty's ratings of students' performances and students' ratings of faculty's teaching are important elements in these efforts to document educational quality. This article discusses selected research related to factors affecting raters' judgements, analyses how changes in the health care environment are influencing such judgements, offers some suggestions to moderate some of the effects and links these influences to the system that upholds professional standards. Ratings are known to have a positive bias (generosity error), provide limited discrimination and often fail to document serious deficits. The potential sources of these problems relate to the mechanics of the rating task, the system used to obtain ratings and factors affecting rater judgement. As managed care demands reduce the time faculty have for teaching, as system-wide disincentives to provide negative ratings proliferate and as social engineering challenges, such as the Americans with Disabilities Act, impose differential standards for students, the natural tendency to avoid giving negative ratings becomes even harder to resist. Ultimately, these forces compromise the capability of faculty to uphold the standards of the profession. The author calls for a national effort to stem the erosion of those standards.     

Problem-based learning: why curricula are likely to show little effect on knowledge and clinical skills

OBJECTIVES: A recent review of problem-based learning's effect on knowledge and clinical skills updated findings reported in 1993. The author argues that effect sizes (ES) seen with PBL have not lived up to expectations (0.8-1.0) and the theoretical basis for PBL, contextual learning theory, is weak. The purposes of this study were to analyse what constitutes reasonable ES in terms of the impacts on individuals and published reports, and to elaborate upon various theories pertaining to PBL. DESIGN: Normal theory is used to demonstrate what various ESs would mean for individual change and a large meta-analysis of over 10 000 studies is referred to in identifying typical ESs. Additional theories bearing upon PBL are presented. RESULTS: Effect sizes of 0.8-1.0 would require some students to move from the bottom quartile to the top half of the class or more. The average ES reported in the literature was 0.50 and many commonly used and accepted medical procedures and therapies are based upon studies with ESs below 0.50. CONCLUSIONS: Effect sizes of 0.8-1.0 are an unreasonable expectation from PBL because, firstly, the degree of changes that would be required of individuals would be excessive, secondly, leading up to medical school, students are groomed and selected for success in a traditional curriculum, expecting them to do better in a PBL curriculum than a traditional curriculum is an unreasonable expectation, and, thirdly, the average study reported in the literature and many commonly used and accepted medical procedures and therapies are based upon studies having lesser ESs. Information-processing theory, Cooperative learning, Self-determination theory and Control theory are suggested as providing better theoretical support for PBL than Contextual learning theory. Even if knowledge acquisition and clinical skills are not improved by PBL, the enhanced work environment for students and faculty that has been consistently found with PBL is a worthwhile goal.     

Oculomotor palsy and supraclinoid internal carotid artery aneurysms. Personal experience and review of the literature

Oculomotor palsy related to the presence of an intracranial aneurysm arising from the supraclinoid internal carotid artery (ICA) is a well known and described clinical condition. Recent microanatomical and clinical evidences seem to demonstrate that the pathophysiology of the aneurysm-related III nerve palsy could be interpreted as that of any other cranial nerve's neurovascular compression syndrome. The authors review their personal experience with supraclinoid ICA aneurysms related to oculomotor palsy and the data of the literature, aiming to elucidate a better clinical, therapeutic and prognostic correlation to these factors.     

Symptomatic subdural hygroma after petroclival meningioma surgery. Case report of a intractable complication

Although subdural hygroma development after craniotomy or aneurysm surgery is a well-known complication and subdural peritoneal or V-P shunt are commonly successful procedures, there are situations that cannot be treated by available surgical options. We reported a case of a 28-year-old young man who developed a symptomatic subdural hygroma after removal of petroclival meningioma. This hygroma increased in size and became bilateral in spite of implantation of V-P with programmable valve at open pressure variable from 30 to 180 mmH2O, placement of subdural-peritoneal shunt with low-low valve or without valve and external diversion. The occurrence of this case showed that there other factors can play role in hygroma development as disturbance of normal CSF dynamic with shunt of CSF from basal arachnoidal to subdural spaces secondary to surgery and/or slow growth of petroclival meningioma as well as postoperative progressive cerebral atrophy. Actually there are not effective diagnostic tools to detect causes and therefore, there are restricted therapeutic possibilities. This potential and serious complication should be always considered when planning petroclival meningioma surgery because of the severe consequences on functional outcome.