Sar management in emergency MRI

Congress:

ECR 2020

Poster Number:

C-12789

Type:

Scientific Exhibit

Keywords:

Performed at one institution, Experimental, Retrospective, Trauma, Education and training, Acute, Technical aspects, Safety, MR, Neuroradiology spine, Neuroradiology brain, Emergency, MRI

Authors:

M. Gentile¹, A. GUIDI², S. Gaudino³, A. Fidanzio³, L. Bonomo³, C. Colosimo³; ¹Roma/IT, ²Anguillara Sabazia (RM)/IT, ³Rome/IT

DOI:

10.26044/ecr2020/C-12789

DOI-Link:

https://dx.doi.org/10.26044/ecr2020/C-12789

Fig. 1: Methods and materials

Fig. 2: MR Images

Fig. 3: Brain recommended protocol - Philips Ingenia 1.5T

Fig. 4: Spine recommended protocol - Philips ingenia 1.5T

Fig. 5: Brain recommended protocol - GE Optima 450 GEM 1.5T

Fig. 6: Spine recommended protocol - GE Optima 450 GEM 1.5T

Purpose

The indications for an emergency MRI in Neuroradiology are as follows: BRAIN Encephalitis; Demyelination with acute neurologic changes; Emergency stroke decision-making in pregnancy, wake-up stroke 2.SPINE/SPINAL CORD Spinal infection (i.e. epidural abscess); Spinal cord compression (burst fracture, tumors, etc); Spinal trauma (epidural hemorrhage, etc). The purpose of the study is to establish a suitable protocol for the examination of the head and the spine in an emergency MRI. SAR (Specific Absorption Rate) is a measure of the rate at which energy is absorbed by the...

Methods and materials

From January 2018 to December 2019, we performed several emergency magnetic resonance imaging examinations. Our experience and the revision of magnetic resonance imaging examinations in 2019 has allowed us to design the following protocols (see section: results). The RM tomographs used were the following: GE Optima MR450W 1.5T GEM suite The coils used were the following: GEM head and neck unit:S/I coverage 50 cm combined with PA+AA, up to 28 elements in FOV combined with PA+AA, GEM anterior array: 54cm anatomical coverage (S/I), up to...

Results

Parameters and options that can be adjusted to reduce B1+RMS include, the following: Increase the RF pulse duration; Utilize a “Low SAR” mode or “Normal mode”; Increase the repetition time (TR) without reducing the number of slices; Reduce the number of slices for a given TR; Reduce the numbers of echoes (Turbo factor or Echo Train Length); Reduce the refocusing angle (FSE sequences); Reduce the flip angle (e.g., for gradient echo pulse sequences); Use a GRE sequence instead of a spin-echo or fast spin-echo pulse...

Conclusion

In an emergency MRI use attached protocols, low SAR mode and dB/dT normal. Keep B1+RMS ≤2. It is essential that emergency protocols are pre-set and should not rely on sudden management. The use of mr-safe pads is essential to avoid contact of the patient's skin with the magnet and coils. The team relationship that links the various professional roles must be an expression not of a mere sum of activities that work in a hermetic manner but of synergism between them. Emanuel Kanal, Professor of...

Personal information and conflict of interest

M. Gentile; Rome/IT - nothing to disclose A. Guidi; Anguillara Sabazia (RM)/IT - nothing to disclose L. Bonomo; Rome/IT - nothing to disclose A. Fidanzio; Rome/IT - nothing to disclose C. Colosimo; Rome/IT - nothing to disclose S. Gaudino; Rome/IT - nothing to disclose

References

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