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Although rehabilitation practice for most patients consists of a combined use of thermotherapy that is produced from diathermy devices resulting faster and deeper heating to the patient, major concerns about occupational exposure to electromagnetic radiation for the operators must be considered. In most occasions, physiotherapists have involved multi-hour treatment sessions to different patients, resulting overuse of the diathermy device. Recently, our team along with other groups have raised serious concerns about the occupational safety aspects related to microwave diathermy (MWD) use. Driven by these recent reports, in this work, we tried to investigate the in vitro effects of a physiotherapist routine MWD device regarding its potential inflammatory biological effects that could be evoked in human cultured monocytes. Our results show that MWD does not alter the integrity of the cell membrane and, consequently, the viability of monocytes as assessed by Trypan blue and MTT measurements. Then again, members of the MAPK family (p38 and ERK1/2) were activated upon MWD exposure at 5-30 min, eventually leading to a time-dependent considerable increase in TNF-α production, a key pro-inflammatory mediator. Our results are indicative of a stress-activated phenomenon of monocytes upon MWD radiation, which could trigger potential hazardous cellular outcomes due to thermal and/or non-thermal bystander effects. Our results deserve further investigation, planned by our team in due course, to delineate the clinical correlations of these findings.

Purpose. Coronary artery ectasia (CAE) is defined as a dilatation of an arterial segment to a diameter at least 1.5 times that of the adjacent artery. It is characterized by slow flow, predisposing to thrombosis. The TIMI frame count (TFC) technique has been successfully used for the assessment of coronary flow velocity using coronary angiograms (CA). Our aim was to compare TFC with magnetic resonance peak flow velocity (PFV) for the evaluation of the coronary flow in patients with CAE. Methods. Fifteen male patients with CAE, aged 45–60 yrs, and 15 age-matched male controls were studied by both techniques. Only patients without coronary obstructive disease were included. Magnetic resonance coronary angiography (MRA) was performed with a 1.5T scanner. The most ectatic part of the proximal 1/3 of the vessel involved was examined. Velocity-encoded MR images were acquired in a double oblique imaging plane, which was perpendicular to the same ectatic segment. The findings were compared with TFC results. Results. Ten patients had RCA ectasia and five LAD ectasia. In CAE patients, peak flow velocity was 10.7 ± 1.4 cm/sec in RCA and 11.4 ± 2.3 cm/sec in LAD. TFC was 42.9 ± 7.4 in RCA and 52.0 ± 20.1 in LAD. In controls, peak flow velocity was 18.1 ± 1.9 in RCA and 21.0 ± 1.7 cm/sec in LAD. TFC was 20.4 ± 1.59 in RCA and 19.8 ± 1.12 in LAD. Controls had significantly higher peak flow velocity (p < 0.001) and lower TFC (p < 0.001) in both RCA and LAD, compared to patients with CAE. In patients with CAE, there was a negative correlation between PFV and TFC measurements (r = 0.74, p < 0.001). Conclusion. Coronary flow in CAE patients can be assessed both by TFC and PFV. The noninvasive nature of PFV gives the opportunity for serial, easily repeatable, flow evaluation in these patients.

Coronary artery ectasia (CAE) is defined as a dilatation of an arterial segment to a diameter at least 1.5 times that of the adjacent normal artery. The correct follow-up of ectatic vessels is hampered by the need for repeat angiograms. In this work we compared quantitative coronary angiography (QCA) measurements of the diameter of the proximal most ectatic part of coronary vessels, with corresponding measurements obtained by magnetic resonance angiography (MRA) using both gradient echo and turbo spin echo imaging sequences. Fifteen patients (14 male), aged 45-65 years, with known CAE were prospectively studied. Two electrocardiogram (ECG)-triggered pulse sequences were implemented for coronary magnetic resonance angiography. The first was a three-dimensional (3D), segmented, k-space gradient-echo sequence, employing a T2-weighted preparation prepulse and a frequency-selective, fat-saturation prepulse to enhance "white blood" (WB) contrast of the coronary arteries. The second sequence was an M2D dual Inversion Recovery (IR) Turbo Spin-Echo with a linear k-space acquisition scheme, providing "black-blood" (BB) contrast of the coronaries. All scans were carried out with the patient free breathing using a 2D, real-time Navigator beam, for respiratory motion tracking and gating. All patients underwent QCA, and the diameter of the proximal most ectatic part of each vessel was measured and compared with "white-blood" and "black-blood" MRA measurements. The average length of continuously visualized LM, LAD, LCx, and RCA by MRA was 2.5 +/- 0.3, 5.8 +/- 0.8, 3.9 +/- 1.0, and 7.2 +/- 1.2 cm, respectively. There were no statistically significant differences between diameter measurements of the proximal most ectatic part of each vessel, obtained with WB and BB sequences. There was a close correlation between MRA and QCA measurements (r = 0.87, p < 0.001). Bland-Altman analysis showed no systematic differences between the examined methods, over the whole range of vessel diameters measured. Coronary MRA is in close correlation with QCA for CAE detection. Magnetic resonance angiography, being noninvasive, may prove of significant value for the efficient follow-up of these patients.

In cine cardiac magnetic resonance imaging (MRI) studies, for any preset imaging parameters the number of phases per cardiac cycle for a single slice is proportional to breath-hold duration. We investigated the relationship between the accuracy of measurement of left ventricular (LV) end-diastolic and end-systolic volumes (EDV and ESV, respectively), mass and ejection fraction (EF), and the number of phases acquired per cardiac cycle. Twelve adult volunteers underwent cardiac MRI and five complete LV functional studies were obtained with 8, 11, 14, 17, and 20 phases per cardiac cycle. We calculated LV volumes, EF, and mass for each acquisition, and compared them using the 20-phase acquisition as the reference standard. The scan duration was proportional to the number of phases acquired. There was a systematic underestimation of LV, EDV, and EF, with decreasing number of phases. Differences from the reference standard became significant for the 8-phase acquisition (p0.05). Subgroup analysis showed that only those with slower heart rates (65/min) had significant differences in EDV, but not in EF, for the 8-phase acquisition. For those with faster heart rates, no differences were detected between the different acquisitions. There were no significant differences between all acquisitions for the LV ESV and mass. We conclude that at least 11 phases per cardiac cycle are needed to maintain accuracy for cine cardiac MRI studies. Decreasing the number of phases per cardiac cycle beyond this cutoff may introduce significant error of measurement, particularly for the left ventricular EDV and EF and especially for those with bradycardia, and should be avoided.