Diffusion MR imaging acquisition and analytics for microstructural delineation in preclinical models of TBI

Significant progress has been made toward improving both the acquisition of clinical diffusion-weighted imaging (DWI) data and its analysis in the uninjured brain, through various techniques including a large number of model-based solutions that have been proposed to fit for multiple tissue compartments, and multiple fibers per voxel. While some of these techniques have been applied to clinical traumatic brain injury (TBI) research, the majority of these technological enhancements have yet to be fully implemented in the preclinical arena of TBI animal model-based research. In this review, we describe the requirement for preclinical, MRI-based efforts to provide systematic confirmation of the applicability of some of these models as indicators of tissue pathology within the injured brain. We review how current DWI techniques are currently being used in animal TBI models, and describe how both acquisition and analytic techniques could be extended to leverage the progress made in clinical work. Finally, we highlight remaining gaps in the preclinical pipeline from data acquisition to final analysis that currently have no real, preclinical-based correlate.

The New Classes of Synthetic Illicit Drugs Can Significantly Harm the Brain: A Neuro Imaging Perspective with Full Review of MRI Findings

Synthetic drugs contain substances that are pharmacologically similar to those found in traditional illicit drugs. Some of the most commonly abused synthetic drugs include synthetic marijuana, bath salts, ecstasy, N-bomb, methamphetamine and anabolic steroids. Many of them share the same chemical properties and physiologic responses with the drugs they mimic and may exaggerate the pathologic response in the brain leading to addiction. These drugs have detrimental (and often irreversible) effects on the brain and primarily affect the central nervous system by two mechanisms: 1) Neural hyper stimulation via increasing activation of certain neurotransmitters (norepinephrine, dopamine, and serotonin), 2) Cause significant reduction in CNS neural connectivity affecting various brain regions such as the basal ganglia, hippocampus, cerebellum, parietal lobe, and globus pallidus. Furthermore these drugs sometimes have severe, life-threatening adverse effects on the human body. A few structural MRI studies have been conducted in synthetic drug abusers to reveal the effects of these drugs on the brain parenchyma. This review article will describe the potential brain imaging findings in synthetic drug abusers as demonstrated by several case reports and the primary literature.

Psychological interventions for symptomatic management of non-specific chest pain in patients with normal coronary anatomy

BACKGROUND

Recurrent chest pain in the absence of coronary artery disease is a common problem which sometimes leads to excess use of medical care. Although many studies have examined the causes of pain in these patients, few clinical trials have evaluated treatment. This is an update of a Cochrane review originally published in 2005 and last updated in 2010. The studies reviewed in this paper provide an insight into the effectiveness of psychological interventions for this group of patients.

OBJECTIVES

To assess the effects of psychological interventions for chest pain, quality of life and psychological parameters in people with non-specific chest pain.

SEARCH METHODS

We searched the Cochrane Library (CENTRAL, Issue 4 of 12, 2014 and DARE Issue 2 of 4, 2014), MEDLINE (OVID, 1966 to April week 4 2014), EMBASE (OVID, 1980 to week 18 2014), CINAHL (EBSCO, 1982 to April 2014), PsycINFO (OVID, 1887 to April week 5 2014) and BIOSIS Previews (Web of Knowledge, 1969 to 2 May 2014). We also searched citation lists and contacted study authors.

SELECTION CRITERIA

Randomised controlled trials (RCTs) with standardised outcome methodology that tested any form of psychotherapy for chest pain with normal anatomy. Diagnoses included non-specific chest pain (NSCP), atypical chest pain, syndrome X or chest pain with normal coronary anatomy (as either inpatients or outpatients).

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, extracted data and assessed quality of studies. We contacted trial authors for further information about the included RCTs.

MAIN RESULTS

We included two new papers, one of which was an update of a previously included study. Therefore, a total of 17 RCTs with 1006 randomised participants met the inclusion criteria, with the one new study contributing an additional 113 participants. There was a significant reduction in reports of chest pain in the first three months following the intervention: random-effects relative risk = 0.70 (95% CI 0.53 to 0.92). This was maintained from three to nine months afterwards: relative risk 0.59 (95% CI 0.45 to 0.76). There was also a significant increase in the number of chest pain-free days up to three months following the intervention: mean difference (MD) 3.00 (95% CI 0.23 to 5.77). This was associated with reduced chest pain frequency (random-effects MD -2.26, 95% CI -4.41 to -0.12) but there was no evidence of effect of treatment on chest pain frequency from three to twelve months (random-effects MD -0.81, 95% CI -2.35 to 0.74). There was no effect on severity (random-effects MD -4.64 (95% CI -12.18 to 2.89) up to three months after the intervention. Due to the nature of the main interventions of interest, it was impossible to blind the therapists as to whether the participant was in the intervention or control arm. In addition, in three studies the blinding of participants was expressly forbidden by the local ethics committee because of issues in obtaining fully informed consent . For this reason, all studies had a high risk of performance bias. In addition, three studies were thought to have a high risk of outcome bias. In general, there was a low risk of bias in the other domains. However, there was high heterogeneity and caution is required in interpreting these results. The wide variability in secondary outcome measures made it difficult to integrate findings from studies.

AUTHORS' CONCLUSIONS

This Cochrane review suggests a modest to moderate benefit for psychological interventions, particularly those using a cognitive-behavioural framework, which was largely restricted to the first three months after the intervention. Hypnotherapy is also a possible alternative. However, these conclusions are limited by high heterogeneity in many of the results and low numbers of participants in individual studies. The evidence for other brief interventions was less clear. Further RCTs of psychological interventions for NSCP with follow-up periods of at least 12 months are needed.

The effect of community treatment orders on outcome as assessed by the Health of the Nation Outcome Scales

Many studies of outpatient commitment have assessed effects on health service use rather than psychiatric symptomatology. We examined whether patients on one form of outpatient commitment, community treatment orders (CTOs), had better outcomes on the Health of the Nation Outcome Scales (HoNOS). Cases and controls from three linked Western Australian databases were matched on age, sex, diagnosis and time of hospital discharge. These databases cover the entire state (population=2.3 million). We compared HoNOS scores of CTO cases and controls at baseline, six-, and twelve-month follow-up, using multivariate analyses to further control for confounders. We identified 1296 CTO cases between 2004 and 2009 along with the same number of controls matched on age, sex, discharge date and mental health diagnosis (total n=2592). HoNOS scores were available for 1433 (55%) of the patients who could have had these recorded at baseline (748 CTO cases and 685 controls). There was no significant difference in HoNOS scores at six- and twelve-month follow-up between CTO cases and controls after adjusting for potential confounders at each time-point. Although the study was limited by missing data, outpatient commitment in the form of CTOs may not result in better psychiatric outcomes as measured by the HoNOS.

Diffusional kurtosis imaging of the developing brain

BACKGROUND AND PURPOSE

Diffusional kurtosis imaging is an extension of DTI but includes non-Gaussian diffusion effects, allowing more comprehensive characterization of microstructural changes during brain development. Our purpose was to use diffusional kurtosis imaging to measure age-related microstructural changes in both the WM and GM of the developing human brain.

MATERIALS AND METHODS

Diffusional kurtosis imaging was performed in 59 subjects ranging from birth to 4 years 7 months of age. Diffusion metrics, fractional anisotropy, and mean kurtosis were collected from VOIs within multiple WM and GM structures and subsequently analyzed with respect to age. Diffusional kurtosis tractography images at various stages of development were also generated.

RESULTS

Fractional anisotropy and mean kurtosis both showed age-related increases in all WM regions, reflecting progression of diffusional anisotropy throughout development, predominantly in the first 2 years of life (eg, 70% and 157% increase in fractional anisotropy and mean kurtosis, respectively, from birth to 2 years for the splenium). However, mean kurtosis detected continued microstructural changes in WM past the fractional anisotropy plateau, accounting for more delayed isotropic changes (eg, 90% of maximum fractional anisotropy was reached at 5 months, whereas 90% of maximum mean kurtosis occurred at 18 months for the external capsule). Mean kurtosis may also provide greater characterization of GM maturation (eg, the putamen showed no change in fractional anisotropy but an 81% change in mean kurtosis from birth to 4 years 7 months).

CONCLUSIONS

Mean kurtosis detects significant microstructural changes consistent with known patterns of brain maturation. In comparison with fractional anisotropy, mean kurtosis may offer a more comprehensive evaluation of age-related microstructural changes in both WM and GM and is potentially a valuable technique for studying brain development.

Psychological interventions for symptomatic management of non-specific chest pain in patients with normal coronary anatomy

BACKGROUND

Recurrent chest pain in the absence of coronary artery disease is a common problem that sometimes leads to excess use of medical care. Although many studies examine the causes of pain in these patients, few clinical trials have evaluated treatment. The studies reviewed in this paper provide an insight into the effectiveness of psychological interventions for this group of patients.

OBJECTIVES

To update the previously published systematic review.

SEARCH METHODS

We searched the Cochrane LIbrary (CENTRAL and DARE) (Issue 3 of 4 2011), MEDLINE (1966 to August Week 5, 2011), CINAHL (1982 to Sept 2011) EMBASE (1980 to Week 35 2011), PsycINFO (1887 to Sept Week 1, 2011), and Biological Abstracts (January 1980 to Sept 2011). We also searched citation lists and approached authors.

SELECTION CRITERIA

Randomised controlled trials (RCTs) with standardised outcome methodology that tested any form of psychotherapy for chest pain with normal anatomy. Diagnoses included non-specific chest pain (NSCP), atypical chest pain, syndrome X, or chest pain with normal coronary anatomy (as either inpatients or outpatients).

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion, extracted data and assessed quality of studies. The authors contacted trial authors for further information about the RCTs included.

MAIN RESULTS

Six new RCTs were located and added to the existing trials, therefore, a total of 15 RCTs (803 participants) were included. There was a significant reduction in reports of chest pain in the first three months following the intervention; fixed-effect relative risk = 0.68 (95% CI 0.57 to 0.81). This was maintained from three to nine months afterwards; relative risk = 0.59 (95% CI 0.45 to 0.76). There was also a significant increase in the number of chest pain free days up to three months following the intervention; mean difference = 2.81 (95% CI 1.28 to 4.34). This was associated with reduced chest pain frequency (random-effects mean difference = -2.26 95% CI -4.41 to -0.12) but there was no evidence of effect of treatment on chest pain frequency from three to twelve months (random-effects mean difference -0.81 95% CI -2.35, 0.74). There was no effect on severity (random-effects mean difference = -4.64 (95% CI -12.18 to 2.89) up to three months after the intervention. Overall there was generally a low risk of bias, however, there was high heterogeneity and caution is required in interpreting these results. Wide variability in outcome measures made integration of studies for secondary outcome measures difficult to report on.

AUTHORS' CONCLUSIONS

This review suggests a modest to moderate benefit for psychological interventions, particularly those using a cognitive-behavioural framework, which was largely restricted to the first three months after the intervention. Hypnotherapy is also a possible alternative. The evidence for brief interventions was less clear. Further RCTs of psychological interventions for NSCP with follow-up periods of at least 12 months are needed.

Global survey of national tuberculosis drug policies

SETTING

National tuberculosis (TB) programmes (NTPs) in 100 countries.

OBJECTIVES

To evaluate the relationship between the estimated prevalence of multidrug resistance in previously untreated TB cases and policies regarding sales and distribution of TB drugs, particularly rifampicin (RMP).

DESIGN

Questionnaire survey of national TB drug control policies, completed by NTP managers. Results were correlated with recent World Health Organization estimates of prevalence of drug resistance in new cases of TB.

RESULTS

Questionnaires were received from 100 countries, including 88 low- and middle-income countries (LMICs) and 17 of the 22 high-burden countries. Current policies were considered adequate in only 40 of the 88 LMICs (45%). A higher prevalence of multidrug resistance was associated with fewer years of free availability of TB drugs from the NTP (P = 0.02) and more years of availability of RMP from providers or pharmacies outside the NTP (P = 0.02). Eleven of the 20 countries with the highest prevalence of multidrug resistance had inadequate policies governing sales and distribution of TB drugs.

CONCLUSIONS

These findings suggest that policies regarding sales and distribution of TB drugs should receive more emphasis as part of the global strategy to control drug resistance.

Standardized treatment of active tuberculosis in patients with previous treatment and/or with mono-resistance to isoniazid: a systematic review and meta-analysis

Performing a systematic review of studies evaluating retreatment of tuberculosis or treatment of isoniazid mono-resistant infection, Dick Menzies and colleagues find a paucity of evidence to support the WHO-recommended regimen.

Background

A standardized regimen recommended by the World Health Organization for retreatment of active tuberculosis (TB) is widely used, but treatment outcomes are suspected to be poor. We conducted a systematic review of published evidence of treatment of patients with a history of previous treatment or documented isoniazid mono-resistance.

Methods and Findings

PubMed, EMBASE, and the Cochrane Central database for clinical trials were searched for randomized trials in previously treated patients and/or those with with mono-resistance to isoniazid, published in English, French, or Spanish between 1965 and June 2008. The first two sources were also searched for cohort studies evaluating specifically the current retreatment regimen. In studies selected for inclusion, rifampin-containing regimens were used to treat patients with bacteriologically confirmed pulmonary TB, in whom bacteriologically confirmed failure and/or relapse had been reported. Pooled cumulative incidences and 95% CIs of treatment outcomes were computed with random effects meta-analyses and negative binomial regression. No randomized trials of the currently recommended retreatment regimen were identified. Only six cohort studies were identified, in which failure rates were 18%–44% in those with isoniazid resistance. In nine trials, using very different regimens in previously treated patients with mono-resistance to isoniazid, the combined failure and relapse rates ranged from 0% to over 75%. From pooled analysis of 33 trials in 1,907 patients with mono-resistance to isoniazid, lower failure, relapse, and acquired drug resistance rates were associated with longer duration of rifampin, use of streptomycin, daily therapy initially, and treatment with a greater number of effective drugs.

Conclusions

There are few published studies to support use of the current standardized retreatment regimen. Randomized trials of treatment of persons with isoniazid mono-resistance and/or a history of previous TB treatment are urgently needed.

Please see later in the article for the Editors' Summary

Background

Every year, nearly ten million people develop tuberculosis—a contagious infection, usually of the lungs—and about 2 million people die from the disease. Tuberculosis is caused by Mycobacterium tuberculosis , bacteria that are spread in airborne droplets when people with the disease cough or sneeze. Its symptoms include a persistent cough, fever, weight loss, and night sweats. Diagnostic tests for tuberculosis include chest X-rays and sputum slide exams and cultures in which bacteriologists try to grow M. tuberculosis from mucus brought up from the lungs by coughing. The disease can be cured by taking several powerful antibiotics regularly (daily or several times a week) for at least 6 months. However, 10%–20% of patients treated for tuberculosis in low- and middle-income countries need re-treatment because the initial treatment fails to clear M. tuberculosis from their body or because their disease returns after they have apparently been cured (treatment relapse). Patients who need re-treatment are often infected with bacteria that are resistant to one or more of the antibiotics commonly used to treat tuberculosis.

Why Was This Study Done?

As part of its strategy to reduce the global burden of tuberculosis, the World Health Organization (WHO) recommends standardized treatment regimens for tuberculosis. For re-treatment, WHO recommends an 8-month course of isoniazid, rifampin, and ethambutol with pyrazinamide and streptomycin added for the first 3 and 2 months, respectively. All these drugs are given daily (the preferred regimen) or three times a week. Unfortunately, although this regimen is now used to treat about 1 million patients each year, it yields poor results, particularly in regions where drug resistance is common. In this study (which was commissioned by WHO to provide the evidence needed for a revision of its treatment guidelines), the researchers undertake a systematic review (a search using specific criteria to identify relevant research studies, which are then appraised) and a meta-analysis (a statistical approach that pools the results of several studies) of randomized trials and cohort studies (two types of study that investigate the efficacy of medical interventions) of re-treatment regimens in previously treated tuberculosis patients, and in patients with infection that was resistant to isoniazid (“mono-resistance”).

What Did the Researchers Do and Find?

The researchers' systematic search for published reports of randomized trials and cohort studies of the currently recommended re-treatment regimen identified no relevant randomized trials and only six cohort studies. In the three cohort studies in which the participants carried M. tuberculosis strains that were sensitive to all the antibiotics in the regimen, failure rates were generally low. However, in the studies in which the participants carried drug-resistant bacteria, failure rates ranged from 9% to 45%. The researchers also identified and analyzed the results of nine trials in which several re-treatment regimens, all of which deviated from the standardized regimen, were used in previously treated patients with isoniazid mono-resistance. In these trials, the combined failure and relapse rates ranged from 0% to more than 75%. Finally, the researchers analyzed the pooled results of 33 trials that investigated the effect of various regimens on nearly 2,000 patients (some receiving their first treatment for tuberculosis, some being re-treated) with isoniazid mono-resistance. This meta-analysis showed that lower relapse, failure, and acquired drug resistance rates were associated with longer duration of rifampicin treatment, use of streptomycin, daily therapy early in the treatment, and regimens that included a greater number of drugs to which the M. tuberculosis carried by the patient were sensitive.

What Do These Findings Mean?

These findings reveal that there is very little published evidence that supports the regimen currently recommended by WHO for the re-treatment of tuberculosis. Furthermore, this limited body of evidence is a patchwork of results gleaned from a few cohort studies and a set of randomized trials not specifically designed to test the efficacy of the standardized regimen. There is an urgent need, therefore, for a concerted international effort to initiate randomized trials of potential treatment regimens in both previously untreated and previously treated patients with all forms of drug-resistant tuberculosis. Because these trials will take some time to complete, the limited findings of the meta-analysis presented here may be used in the meantime to redesign and, hopefully, improve the current standardized re-treatment regimen. In fact, the revised WHO TB treatment guidelines will provide updated recommendations for patients with previously treated TB.

Additional Information

Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000150 .

Effect of duration and intermittency of rifampin on tuberculosis treatment outcomes: a systematic review and meta-analysis

BACKGROUND

Treatment regimens for active tuberculosis (TB) that are intermittent, or use rifampin during only the initial phase, offer practical advantages, but their efficacy has been questioned. We conducted a systematic review of treatment regimens for active TB, to assess the effect of duration and intermittency of rifampin use on TB treatment outcomes.

METHODS AND FINDINGS

PubMed, Embase, and the Cochrane CENTRAL database for clinical trials were searched for randomized controlled trials, published in English, French, or Spanish, between 1965 and June 2008. Selected studies utilized standardized treatment with rifampin-containing regimens. Studies reported bacteriologically confirmed failure and/or relapse in previously untreated patients with bacteriologically confirmed pulmonary TB. Pooled cumulative incidences of treatment outcomes and association with risk factors were computed with stratified random effects meta-analyses. Meta-regression was performed using a negative binomial regression model. A total of 57 trials with 312 arms and 21,472 participants were included in the analysis. Regimens utilizing rifampin only for the first 1-2 mo had significantly higher rates of failure, relapse, and acquired drug resistance, as compared to regimens that used rifampin for 6 mo. This was particularly evident when there was initial drug resistance to isoniazid, streptomycin, or both. On the other hand, there was little evidence of difference in failure or relapse with daily or intermittent schedules of treatment administration, although there was insufficient published evidence of the efficacy of twice-weekly rifampin administration throughout therapy.

CONCLUSIONS

TB treatment outcomes were significantly worse with shorter duration of rifampin, or with initial drug resistance to isoniazid and/or streptomycin. Treatment outcomes were similar with all intermittent schedules evaluated, but there is insufficient evidence to support administration of treatment twice weekly throughout therapy.

Pseudoaneurysm of inferior epigastric artery complicating ileostomy construction

Pseudoaneurysm of the inferior epigastric artery complicating ileostomy construction is described in a 25-year-old woman. She underwent total abdominal perineal proctocolectomy with a permanent ileostomy constructed through the right rectus muscle. 15 days later, she abruptly developed significant bleeding through the ileostomy that recurred two more times. Endoscopy performed through the ileostomy stoma revealed a small ulcer 8 cm from the stomal opening. The distal segment of ileum containing the bleeding site was resected, and on-table examination of the lesion revealed an underlying tear in the inferior epigastric artery wall. The patient recovered after the operation.