Mel B. Glenn

Depression amongst outpatients with traumatic brain injury.

The incidence of depression and its association with subject characteristics in outpatients with traumatic brain injury (TBI) were investigated. Logistic regression was estimated with depressed/not-depressed as the dependent variable in 41 outpatients with TBI who filled out the Beck Depression Inventory-II (BDI-II). Twenty-four of 41 subjects (59%) scored in the depressed categories based on BDI-II scores >13. Fourteen (34%) scored in the moderate or severe depression categories (BDI>19). Logistic regression demonstrated a positive relationship amongst depression and age, female gender, mild TBI, and use of antidepressant and stimulant drugs; and a negative relationship between depression and violent aetiology of injury. ANOVA demonstrated that individuals with mild TBI were significantly older than those with moderate or severe TBI, which might account for the association between depression and age. The implications of these results are discussed.

Lithium carbonate for aggressive behavior or affective instability in ten brain-injured patients.

Lithium carbonate (LiCO3) was used to treat 10 brain-injured patients with severe, unremitting, aggressive, combative, or self destructive behavior or severe affective instability. Five patients had a dramatic response that resulted in significant improvement in their participation in a rehabilitative program. One other patient had a moderate response. A seventh patient improved dramatically, but regressed after 7 wk. Three other patients had neurotoxic side effects that precluded continued use of the medication. Two of them were simultaneously taking neuroleptic agents. These case reports provide further evidence that LiCO3 can be a useful medication in the treatment of aggressive behavior and affective instability after brain injury, but that it has significant potential for neurotoxicity in this population, particularly when used in conjunction with neuroleptic agents.

Prediction of Memory Rehabilitation Outcomes in Traumatic Brain Injury by Using Functional Magnetic Resonance Imaging

OBJECTIVE To evaluate the ability of functional magnetic resonance imaging (fMRI) measures collected from people with traumatic brain injury (TBI) to provide predictive value for rehabilitation outcomes over and above standard predictors. DESIGN Prospective study. SETTING Academic medical center. PARTICIPANTS Persons (N=54) with TBI greater than 1 year postinjury. INTERVENTION A novel 12-session group rehabilitation program focusing on internal strategies to improve memory. MAIN OUTCOME MEASURE The Hopkins Verbal Learning Test-Revised (HVLT-R) delayed recall score. RESULTS fMRI measures were collected while participants performed a strategically directed word memorization task. Prediction models were multiple linear regressions with the following primary predictors of outcome: age, education, injury severity, preintervention HVLT-R, and task-related fMRI activation of the left dorsolateral and left ventrolateral prefrontal cortex (VLPFC). Baseline HVLT-R was a significant predictor of outcome (P=.007), as was injury severity (for severe vs mild, P=.049). We also found a significant quadratic (inverted-U) effect of fMRI in the VLPFC (P=.007). CONCLUSIONS This study supports previous evidence that left prefrontal activity is related to strategic verbal learning, and the magnitude of this activation predicted success in response to cognitive memory rehabilitation strategies. Extreme under- or overactivation of VLPFC was associated with less successful learning after rehabilitation. Further study is necessary to clarify this relationship and to expand and optimize the possible uses of functional imaging to guide rehabilitation therapies.

Regional Brain Morphometry Predicts Memory Rehabilitation Outcome after Traumatic Brain Injury

Cognitive deficits following traumatic brain injury (TBI) commonly include difficulties with memory, attention, and executive dysfunction. These deficits are amenable to cognitive rehabilitation, but optimally selecting rehabilitation programs for individual patients remains a challenge. Recent methods for quantifying regional brain morphometry allow for automated quantification of tissue volumes in numerous distinct brain structures. We hypothesized that such quantitative structural information could help identify individuals more or less likely to benefit from memory rehabilitation. Fifty individuals with TBI of all severities who reported having memory difficulties first underwent structural MRI scanning. They then participated in a 12 session memory rehabilitation program emphasizing internal memory strategies (I-MEMS). Primary outcome measures (HVLT, RBMT) were collected at the time of the MRI scan, immediately following therapy, and again at 1-month post-therapy. Regional brain volumes were used to predict outcome, adjusting for standard predictors (e.g., injury severity, age, education, pretest scores). We identified several brain regions that provided significant predictions of rehabilitation outcome, including the volume of the hippocampus, the lateral prefrontal cortex, the thalamus, and several subregions of the cingulate cortex. The prediction range of regional brain volumes were in some cases nearly equal in magnitude to prediction ranges provided by pretest scores on the outcome variable. We conclude that specific cerebral networks including these regions may contribute to learning during I-MEMS rehabilitation, and suggest that morphometric measures may provide substantial predictive value for rehabilitation outcome in other cognitive interventions as well.

Cutoff score on the apathy evaluation scale in subjects with traumatic brain injury

This cross-sectional study was designed to determine a cutoff score on the Apathy Evaluation Scale (AES) that predicts a clinicians designation of a subject with TBI as apathetic or not. Forty-five outpatients with TBI completed the AES-S, and 37 family members, friends, or significant others filled out the AES-I. Three clinicians prospectively gave their impressions of the presence or absence of apathy and retrospectively chose the degree of apathy on a 7-point subjective rating scale. The data was analysed by logistic regression and Receiver Operating Characteristic (ROC) curve. Sensitivity and specificity were calculated. No cutoff score on the AES-S or AES-I was found to have reasonable sensitivity and specificity with respect to the ability to predict the clinicians designation of a subject as apathetic. The AES requires further study if it is to be used to measure apathy following TBI.

Neurophysiological Alterations During Strategy-Based Verbal Learning in Traumatic Brain Injury

Background. Verbal learning and strategic processing deficits are common sequelae of traumatic brain injury (TBI); however, the neurophysiological mechanisms underlying such deficits remain poorly understood. Methods. We performed functional magnetic resonance imaging (fMRI) in 25 individuals with chronic TBI (>1 year after injury) and 20 matched healthy controls. Subjects were scanned while encoding word lists, with free recall and recognition assessed after each scanning run. To vary the strategic processing load, participants learned semantically unrelated words (Unrelated condition), semantically related words under null instruction conditions (Spontaneous condition), and semantically related words following training on the use of a semantic clustering strategy (Directed condition). Results. Behavioral performance on recall, recognition, and semantic clustering improved significantly as follows: Unrelated < Spontaneous < Directed. Individuals with TBI exhibited impaired yet parallel behavioral performance relative to control participants. The fMRI measures of brain activity during verbal encoding revealed decreased activity in participants with TBI relative to controls in left dorsolateral prefrontal cortex (DLPFC; BA 9) and in a region spanning the left angular and supramarginal gyri (BA 39/40). Functional connectivity analysis revealed evidence of a functional—but not anatomical—breakdown in the connectivity between the DLPFC and other regions specifically when participants with TBI were directed to use the semantic encoding strategy. Conclusion. After TBI, the DLPFC appears to be decoupled from other active brain regions specifically when strategic control is required. We hypothesize that approaches designed to help re-couple DLPFC under such conditions may aid TBI cognitive rehabilitation.

Clinician influences on use of portable electronic memory devices in traumatic brain injury rehabilitation.

Primary objective: To explore the relationship between a group of clinicians’ own experience, training and confidence with portable electronic memory devices and their use of the same in traumatic brain injury (TBI) rehabilitation. Research design: Survey study. Methods and procedures: Eighty-one TBI clinicians from various disciplines and work settings completed a survey distributed in person or by mail. Main outcomes and results: Twenty-nine respondents (36%) reported using portable electronic memory devices with patients with TBI. Using regression analysis, respondent device training and confidence teaching patients device use were statistically associated with respondents’ use of such devices in TBI rehabilitation. Conclusions: Portable electronic memory device use with persons following TBI may be under-utilized. The importance of ongoing clinician training and of maximizing clinician confidence utilizing these devices in TBI rehabilitation is emphasized. The representativeness of the respondent sample is discussed. Specific training strategies and continued research needs are presented.

An illustration of clinical gait laboratory use to improve rehabilitation management.

The purpose of this report is to illustrate the utility of a gait laboratory as a simple, straightforward aid to psychiatric care. The evaluation and management of a patient with spastic paresis and reduced knee flexion in swing (stiff-legged gait), using quantitative gait analysis, are provided. Spastic quadriceps activity during swing was thought to be the cause of reduced knee flexion, based on traditional physiatric history and physical examination. Gait laboratory analysis, including lower extremity kinematic, kinetic and dynamic electromyographic measurements, demonstrated that the quadriceps were not inappropriately active, as had been expected and suggested, instead, that the reduced knee flexion was secondary to dynamic ankle plantar flexor weakness. Modification of an ankle-foot-orthosis and specific exercises to strengthen the ankle plantar flexors were, therefore, prescribed and resulted in kinematic and kinetic improvements at subsequent gait analysis and a subjective feeling by the patient that gait was better. Gait laboratory analysis was useful in determining the optimal rehabilitation plan.

Electronic reminding technology following traumatic brain injury: effects on timely task completion.

Objective:To determine whether automated reminders from 2 contemporary personal digital assistant (PDA) devices produce higher rates of timely task completion in people with traumatic brain injury (TBI). Setting:Outpatient and community rehabilitation settings. Participants:Thirty-six adults aged 18 to 66 years with TBI and self-determined complaints of memory impairment. Measures:Timely completion rates for assigned memory tasks under 4 randomly assigned memory aid conditions. Results:Significantly, higher completion rates were found when using either PDA device when compared with a combined baseline and paper memory aid condition (for Palm OS device, Incidence Rate Ratio [IRR] = 2.14, P < .0005, CI [confidence interval] = 1.77–2.59; for Microsoft Pocket PC OS device, IRR = 1.47, P < .001, CI = 1.18–1.82). A significant difference in completion rates was also found between the 2 PDA devices (IRR = 1.46, P < .0005, CI = 1.26–1.70), with the Palm version producing the better scores. Conclusions:Substantially higher rates of task completion (more than double in some cases) when using either PDA device suggest that rehabilitation clinicians can make productive use of PDA-based memory aids in their TBI patient populations. The strength of the effects of PDA device usage argues for further investigation of the impact of device usage on quality-of-life and costs of care, and of personal and caregiver factors predictive of successful and sustained device usage.

Anterior pituitary dysfunction after traumatic brain injury, Part I.

W ITH the numerous complications that can result from traumatic brain injury (TBI), the diagnosis and treatment of anterior pituitary hypofunction is often not seen as a high priority. When physicians think of hypopituitarism, they often concern themselves with syndromes that result from the posterior pituitary such as diabetes insipidus (DI) or the syndrome of inappropriate antidiuretic hormone secretion (SIADH). DI is a syndrome that is most commonly found early postinjury and rehabilitation physicians are not usually responsible for medically managing it. They more commonly are faced with SIADH, which can account for between 20% to 40% of all cases of serum hypoosmolarity.1 Abnormalities that involve the hormones controlled by the anterior pituitary (thyroid stimulating hormone, TSH, which controls thyroxine; growth hormone, GH, which controls insulin growth factor I (IGF-1); adrenocor-