Axial loading during MRI reveals deviant characteristics within posterior IVD regions between low back pain patients and controls.

PURPOSE: To investigate differences in functional intervertebral disk (IVD) characteristics between low back pain (LBP) patients and controls using T2-mapping with axial loading during MRI (alMRI). METHODS: In total, 120 IVDs in 24 LBP patients (mean age 39 years, range 25-69) were examined with T2-mapping without loading of the spine (uMRI) and with alMRI (DynaWell® loading device) and compared with 60 IVDs in 12 controls (mean age 38 years, range 25-63). The IVD T2-value was acquired after 20-min loading in five regions of interests (ROI), ROI1-5 from anterior to posterior. T2-values were compared between loading states and cohorts with adjustment for Pfirrmann grade. RESULTS: In LBP patients, mean T2-value of the entire IVD was 64 ms for uMRI and 66 ms for alMRI (p = 0.03) and, in controls, 65 ms and 65 ms (p = 0.5). Load-induced T2-differences (alMRI-uMRI) were seen in all ROIs in both patients (0.001 > p < 0.005) and controls (0.0001 > p < 0.03). In patients, alMRI induced an increase in T2-value for ROI1-3 (23%, 18% and 5%) and a decrease for ROI4 (3%) and ROI5 (24%). More pronounced load-induced decrease was detected in ROI4 in controls (9%/p = 0.03), while a higher absolute T2-value was found for ROI5 during alMRI in patients (38 ms) compared to controls (33 ms) (p = 0.04). CONCLUSION: The alMRI-induced differences in T2-value in ROI4 and ROI5 between patients and controls most probably indicate biomechanical impairment in the posterior IVD regions. Hence, alMRI combined with T2-mapping offers an objective and clinical feasible tool for biomechanical IVD characterization that may deepen the knowledge regarding how LBP is related to altered IVD matrix composition. These slides can be retrieved under Electronic Supplementary Material.

With axial loading during MRI diurnal T2-value changes in lumbar discs are neglectable: a cross sectional study.

BACKGROUND: Axial loading during MRI (alMRI) combined with T2 mapping recently was shown as a promising method to reveal biomechanical intervertebral disc (IVD) characteristics. This feasibility study aims to investigate whether there is a diurnal variation in the IVD T2-value when using alMRI. This is of importance for the planning of when to perform alMRI investigations and for interpretations of alMRI findings in relation to clinical symptoms. METHODS: Six healthy volunteers (30 lumbar discs), were examined with alMRI at three different sessions during 1 day. To be representative for a low back pain cohort in terms of age and IVD degeneration the included participants had a wide age range (27-63y) and all Pfirrmann grades represented. The T2-values were measured in five IVD regions of interest (ROI). The ROIs were equally large in sagittal plane with ROI1 representing anterior parts of the IVD, ROI5 posterior IVD parts and ROI2-4 the parts in between. RESULTS: T2-values of the entire IVD varied between 38 and 138 ms at 7 am, 33-143 ms at 11.30 am, and 31-147 ms at 4 pm with large regional IVD variations at all time points. No significant alterations of the T2-values over the day were found, neither for the entire IVD (p = 0.4) nor for the various ROIs (p = 0.2-1.0). Neither when correlated to Pfirrmann grade, any significant diurnal T2-value changes were found. CONCLUSIONS: With alMRI, only minor diurnal T2-value changes were found in the lumbar discs. Nonsignificant and neglectable diurnal changes are advantageous both for research purposes, as well as in the clinical setting, giving comparable and robust data regardless of at what time-point the alMRI is performed.

The antidepressant response to tricyclics in major depressives is accelerated with adjunctive use of methylphenidate.

Standard tricyclic antidepressant (TCA) treatment usually entails response latencies of 2 to 4 weeks. To accelerate the antidepressant response, methylphenidate (MPH) was administered together with standard antidepressants in an open label trial. Twenty inpatients (9 females, 11 males) met DSM-III-R criteria for major depressive episode (15 unipolar and 2 bipolar), depression NOS (n = 2), or Research Diagnostic Criteria for schizoaffective illness, depressed type (n = 1). Following evaluation for depression, patients received an open-label oral MPH stimulation trial (MST), in 1 or 2 dosages of 5 to 15 mg at 0900 and 1000 hours. Twenty patients with positive MST response were treated with TCAs combined with MPH (5-15 mg/d). Therapeutic response was defined as 50 percent decline in the Hamilton Rating Scale for Depression. Six of 20 (30%) patients responded after 1 week of combination TCA-MPH, and 10 of 16 (63%) after 2 weeks. Adverse effects of the combination treatment included: dizziness and orthostatic blood pressure changes (n = 3), dry mouth (n = 3), increased anxiety (n = 3), and hypomania (n = 1). The severity of adverse effects required cessation of the MPH in 3 patients. Elevated self-ratings of anxiety were associated with lack of improvement after both 1 and 2 weeks. Adjunctive MPH appears to accelerate response to tricyclics in this systematically conducted open trial, and adverse effects of the TCA-MPH combination were usually tolerable. Positive response on the MST may be predictive of beneficial therapeutic outcome, especially in depressed patients without high anxiety levels.(ABSTRACT TRUNCATED AT 250 WORDS)