Abstract
Introduction: The combination of increased magnetic field strength, field gradients and RF power, augments the risk of tissue heating in patients undergoing an MRI examination. This is especially important when the patients have implants or when external devices are in direct contact with the skin. This holds true even in cases in which the devices are MRI compatible and therefore safe in specified MRI environments.
Of particular interest to this case report is skin burns caused by the ECG monitoring equipment. In this context, several cases of ECG electrode related burns have been reported, while burns caused by the ECG cables are less common [1]. This case report presents two unusual cases of skin burns which were caused by MRI safe ECG leads during scanning.
Cases:Two patients suffered third degree burns using MRI approved ECG leads (Medrad® Veris MR Monitor system) in a Siemens Skyra 3.0 Tesla MRI system. MRI sequences: Turbo Spin Echo (TSE) (ETL = 2-27, Scan time = 152-235 seconds), Flip Angles 135-160°, TR = 560-5423 ms). Both patients had elongated burns located on their bellies and therefore caused by the leads and not the electrodes. Both patients were sedated and the burns were not discovered until after they had left the radiology department.
Discussion: Skin burns are usually caused by the 'antenna effect' which is related to the RF pulses and/or the switching of the gradients [2]. Discriminating between the two may be difficult as the result is the same: heating of the ECG system. Positioning of the ECG module in the imaging plane may contribute to heating of the leads due to this effect [3,4]. As this was the case, this may have contributed to the bruns. Furthermore, we believe that the burns were actually caused by the direct skin contact with the leads and a marginal crossing of the assigned compatibility specifications of the leads due to the use of TFE sequences with high SAR values.
MRI compatible monitoring systems are only safe when used with proper care. The presented burn cases may have been avoided if space had been provided between the ECG leads and the skin using a cloth or a foam spacer.
References:
[1] Dempsey, Clin Radiol, 2001; 56: 457-465
[2] Dempsey, J Magn Reson Imaging, 2001; 13: 627-631
[3] Carter, J Neurosurg, 2013; 119: 1082-1084
[4] Tanaka, J Neurosurg, 2012; 117: 1100-1109
Of particular interest to this case report is skin burns caused by the ECG monitoring equipment. In this context, several cases of ECG electrode related burns have been reported, while burns caused by the ECG cables are less common [1]. This case report presents two unusual cases of skin burns which were caused by MRI safe ECG leads during scanning.
Cases:Two patients suffered third degree burns using MRI approved ECG leads (Medrad® Veris MR Monitor system) in a Siemens Skyra 3.0 Tesla MRI system. MRI sequences: Turbo Spin Echo (TSE) (ETL = 2-27, Scan time = 152-235 seconds), Flip Angles 135-160°, TR = 560-5423 ms). Both patients had elongated burns located on their bellies and therefore caused by the leads and not the electrodes. Both patients were sedated and the burns were not discovered until after they had left the radiology department.
Discussion: Skin burns are usually caused by the 'antenna effect' which is related to the RF pulses and/or the switching of the gradients [2]. Discriminating between the two may be difficult as the result is the same: heating of the ECG system. Positioning of the ECG module in the imaging plane may contribute to heating of the leads due to this effect [3,4]. As this was the case, this may have contributed to the bruns. Furthermore, we believe that the burns were actually caused by the direct skin contact with the leads and a marginal crossing of the assigned compatibility specifications of the leads due to the use of TFE sequences with high SAR values.
MRI compatible monitoring systems are only safe when used with proper care. The presented burn cases may have been avoided if space had been provided between the ECG leads and the skin using a cloth or a foam spacer.
References:
[1] Dempsey, Clin Radiol, 2001; 56: 457-465
[2] Dempsey, J Magn Reson Imaging, 2001; 13: 627-631
[3] Carter, J Neurosurg, 2013; 119: 1082-1084
[4] Tanaka, J Neurosurg, 2012; 117: 1100-1109
| Originalsprog | Engelsk |
|---|---|
| Publikationsdato | 3 okt. 2015 |
| Antal sider | 1 |
| Status | Udgivet - 3 okt. 2015 |
| Begivenhed | ESMRMB: 32nd Annual Scientific Meeting - Edinburgh International Conference Centre, Edinburgh, Storbritannien Varighed: 1 okt. 2015 → 3 okt. 2015 Konferencens nummer: 32 |
Konference
| Konference | ESMRMB |
|---|---|
| Nummer | 32 |
| Lokation | Edinburgh International Conference Centre |
| Land/Område | Storbritannien |
| By | Edinburgh |
| Periode | 01/10/2015 → 03/10/2015 |
Emneord
- Magnetic Resonance Imaging
- ECG system
- skin burns
- MRI Safety