A standardised method for measuring magnetisation transfer ratio on MR imagers from different manufacturers--the EuroMT sequence.

Magnetisation transfer ratio (MTR) is increasingly used to evaluate neurological disorders, especially those involving demyelination. It shows promise as a surrogate marker of disease progression in treatment trials in multiple sclerosis (MS) but the value measured is highly dependent on pulse sequence parameters, making it hard to include the technique in large multi-centre clinical trials. The variations can be reduced by a normalisation procedure based on the flip angle and timing of the presaturation pulse, but correction for parameters such as saturation pulse shape, amplitude, duration and offset frequency remains problematic. We have defined a standard pulse sequence, to include a standard presaturation pulse and set of parameters, which can be implemented on scanners from both General Electric and Siemens, and has also been used on Phillips scanners. To validate the sequence and parameters, six European centres measured MTR in the frontal white matter of normal volunteers. It was possible to measure MTR values in controls which were consistent to within approximately +/-2.5 percentage units across sites. This degree of precision may be adequate in many situations. The remaining differences between sites and manufacturers are probably caused by B1 errors

Spontaneous haemoperitoneum in pregnancy and endometriosis : a case series

OBJECTIVE: To report pregnancy outcomes of SHiP (spontaneous haemoperitoneum in pregnancy) and the association with endometriosis. DESIGN: Retrospective case note review. SETTING: Dutch referral hospitals for endometriosis. SAMPLE: Eleven women presenting with 15 events of SHiP. METHODS: In collaboration with the Dutch Working Group on Endometriosis, unpublished cases of SHiP that occurred in the Netherlands between 2010 and 2015 were retrieved. MAIN OUTCOME MEASURES: Maternal and perinatal mortality and morbidity. RESULTS: SHiP occurred predominantly in the second and third trimester of pregnancy. The earliest and major presenting symptom was an acute onset of abdominal pain, often combined with low haemoglobin levels or signs of fetal distress. Imaging was a diagnostic tool when free peritoneal fluid could be observed. For surgical treatment of the bleeding site, a midline laparotomy was mostly needed, the median estimated amount of blood loss was 2000 mL. No fetomaternal or perinatal mortality was reported, despite a high rate of preterm births (54.5%). In all women, endometriosis was diagnosed at a certain moment in time and therefore was probably involved in the pathogenesis of SHiP. Four women showed recurrence of SHiP. In one of these cases the second event of SHiP occurred in a subsequent pregnancy. CONCLUSION: Pregnancy outcomes of SHiP are improving when compared with previous reports, with absent fetomaternal and perinatal mortality in this recent series. Growing knowledge and adequate multidisciplinary intervention may have contributed to these favourable results. Increasing awareness of this serious complication of pregnancy is advocated, especially in women diagnosed with endometriosis. TWEETABLE ABSTRACT: Growing awareness of SHiP is advocated, especially in women diagnosed with endometriosis

Preliminary magnetic resonance study of the macromolecular proton fraction in white matter: a potential marker of myelin?

We report on a new quantitative magnetization transfer (MT) technique that allows for the in vivo estimation of the macromolecular proton fraction (f) and the bound pool T2 relaxation time (T2b), whilst permitting whole brain coverage. In this pilot study, five subjects with multiple sclerosis (MS) and five healthy controls were studied. Both f and T2b were significantly different between MS lesions and normal control white matter (WM). Relationships between f and T1 relaxation time [Spearmans rank correlation coefficient (r(s)) = -0.97, P < 0.001] and f and the magnetization transfer ratio (MTR; r(s) = 0.80, P < 0.001) were observed. Compared with MTR, f and T2b have the potential advantage of relative independence from MT acquisition protocol while offering more pathologically specific information. In particular, f may provide a more direct indication of myelin content in WM

Subcortical Biophysical Abnormalities in Patients with Mood Disorders

Cortical-subcortical circuits have been implicated in the pathophysiology of mood disorders. Structural and biochemical abnormalities have been identified in patients diagnosed with mood disorders using magnetic resonance imaging-related approaches. In this study, we used magnetization transfer (MT), an innovative magnetic resonance approach, to study biophysical changes in both gray and white matter regions in cortical-subcortical circuits implicated in emotional regulation and behavior. Our study samples comprised 28 patients clinically diagnosed with major depressive disorder (MDD) and 31 non-depressed subjects of comparable age and gender. MT ratio (MTR), representing the biophysical integrity of macromolecular proteins within key components of cortical-subcortical circuits-the caudate, thalamic, striatal, orbitofrontal, anterior cingulate and dorsolateral regions-was the primary outcome measure. In our study, the MTR in the head of the right caudate nucleus was significantly lower in the MDD group when compared with the comparison group. MTR values showed an inverse relationship with age in both groups, with more widespread relationships observed in the MDD group. These data indicate that focal biophysical abnormalities in the caudate nucleus may be central to the pathophysiology of depression and critical to the cortical-subcortical abnormalities that underlie mood disorders. Depression may also accentuate age-related changes in the biophysical properties of cortical and subcortical regions. These observations have broad implications for the neuronal circuitry underlying mood disorders across the lifespa