Image quality and cancer visibility of T2-weighted Magnetic Resonance Imaging of the prostate at 7 Tesla

Vos, Eline K.; Lagemaat, M.W.; Barentsz, Jelle O.; Fütterer, JJ; Zámecnik, Patrik; Roozen, H; Orzada, Stephan; Bitz, Andreas K.; Maas, MC; Scheenen, Tom W. J.

doi:10.1007/s00330-014-3234-6

Cited by 34 publications

(22 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Patient studies at 7T involving prostate cancer showed until now satisfactory results for T 2 w (T 2 ‐weighted) imaging compared with 3T and the first results of 1 H and 31 P MRS at 7T were published. Imaging at 7T is technically challenging due to radiofrequency (RF) inhomogeneity, increased tissue heating, and reduced RF field penetration.…”

mentioning

confidence: 99%

Comparing signal‐to‐noise ratio for prostate imaging at 7T and 3T

Steensma

Luttje

Voogt

et al. 2018

Magnetic Resonance Imaging

View full text Add to dashboard Cite

Background In MRI, the signal‐to‐noise ratio (SNR) theoretically increases with B 0 field strength. However, because of attenuation of the radiofrequency (RF) fields at 7T, it is not certain if this SNR gain can be realized for prostate imaging. Purpose/Hypothesis To investigate the SNR gain in prostate imaging at 7T as compared with 3T. It is expected that SNR will improve for prostate imaging at 7T compared with 3T. Study Type Prospective. Subjects Four healthy volunteers and one prostate cancer patient. Field Strength/Sequence All subjects were scanned at 3T and at 7T using optimal coil setups for both field strengths. For all volunteers, proton density‐weighted images were acquired for SNR analysis and actual flip angle imaging (AFI) maps were acquired for correction of measured SNR values. In the patient, a T 2 ‐weighted (T 2 w) image was acquired at 3T and at 7T. Assessment SNR was calculated in the prostate region for all volunteers. SNR was normalized for flip angle, receiver bandwidth, and voxel volume. SNR was also calculated for different sensitivity encoding (SENSE) acceleration factors. Statistical Testing SNR values are represented as the arithmetic mean of SNR values in the prostate. Estimated SNR in the T 2 w image is calculated as the arithmetic mean of the signal intensity (SI) divided by the standard deviation of the SI in a specified zone. Tumor‐to‐tissue contrast is calculated as (SI tumor +SI zone )/( SI tumor ‐SI zone ). Results An increase in SNR ranging from 1.7‐fold to 2.8‐fold was measured in the prostate at 7T in comparison to 3T for four volunteers. At 7T, it is possible to achieve a 4‐fold SENSE acceleration in the left‐right direction with similar SNR to a nonaccelerated 3T image. T 2 w imaging was done at 3T and 7T in one patient, where improved tumor‐to‐tissue contrast was demonstrated at 7T. Data Conclusion SNR improves for prostate imaging at 7T as compared with 3T. Level of Evidence: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;49:1446–1455.

show abstract

mentioning

confidence: 99%

Comparing signal‐to‐noise ratio for prostate imaging at 7T and 3T

Steensma

Luttje

Voogt

et al. 2018

Magnetic Resonance Imaging

View full text Add to dashboard Cite

show abstract

“…Some limitations of MRI are that highfieldstrength MRI systems cur rently available are not configured for intraoperative imaging and surgical guidance, and their resolution is still limited to about 200 μm per voxel in plane and 2-3 mm in the z direction. Future trends in imaging of the prostate using MRI include the introduction of magnets with a higher field strength (for example, 7 T and greater) for continued improvement in sensitivity, resolution, and image acquisition times; [91][92][93][94] however, further safety studies are w arranted before increased field strengths should be used. …”

Section: Magnetic Resonance Imagingmentioning

confidence: 99%

Novel methods for mapping the cavernous nerves during radical prostatectomy

Fried

Burnett

2015

Nat Rev Urol

View full text Add to dashboard Cite

The cavernous nerves, which course along the surface of the prostate gland, are responsible for erectile function. During radical prostatectomy, urologists are challenged in preserving these nerves and their function. Cavernous nerves are microscopic and show variable location in different patients; therefore, postoperative sexual potency rates are widely variable following radical prostatectomy. A variety of technologies, including electrical and optical nerve stimulation, dye-based optical fluorescence and microscopy, spectroscopy, ultrasound and magnetic resonance imaging have all been used to study cavernous nerve anatomy and physiology, and some of these methods are also potential intraoperative methods for identifying and preserving cavernous nerves. However, all of these technologies have inherent limitations, including slow or inconsistent nerve responses, poor image resolution, shallow image depth, slow image acquisition times and/or safety concerns. New and emerging technologies, as well as multimodal approaches combining existing methods, hold promise for improved postoperative sexual outcomes and patient quality of life following radical prostatectomy.

show abstract

“…Nevertheless, an increasing number of clinical feasibility studies at 7 T aim at regions where imaging is hampered by these severe transmit inhomogeneities, for example liver [4,5], kidneys [6], prostate [7,8], female pelvis [9], the hip joints [10,11], the heart [12], the spinal cord [13], and the breasts [14,15], or they cover extended regions such as the complete lower extremities [16].…”

Section: Introductionmentioning

confidence: 99%

Analysis of an Integrated 8-Channel Tx/Rx Body Array for Use as a Body Coil in 7-Tesla MRI

et al. 2017

View full text Add to dashboard Cite

Object:In this work an 8-channel array integrated into the gap between the gradient coil and bore liner of a 7-Tesla whole-body magnet is presented that would allow a workflow closer to that of systems at lower magnetic fields that have a built-in body coil; this integrated coil is compared to a local 8-channel array built from identical elements placed directly on the patient. Results: While the remote array shows a slightly better performance in terms of (B + 1 ) homogeneity, the power efficiency and the SAR efficiency are inferior to those of the local array: the transmit voltage has to be increased by a factor of 3.15 to achieve equal flip angles in a central axial slice. The g-factor calculations show a better parallel imaging g-factor for the local array. The field of view of the integrated array is larger than that of the local array. First in vivo images with the integrated array look subjectively promising. Conclusion:Although some RF performance parameters of the integrated array are inferior to a tight-fitting local array, these disadvantages might be compensated by the use of amplifiers with higher power and the use of local receive arrays. In addition, the distant placement provides the potential to include more elements in the array design.

show abstract

Image quality and cancer visibility of T2-weighted Magnetic Resonance Imaging of the prostate at 7 Tesla

Abstract: • Satisfactory to good T2-weighted image quality of the prostate is achievable at 7T. • Periprostatic lipids appear hypo-intense compared to healthy peripheral zone tissue at 7T. • Prostate cancer is visible on T2-weighted MRI at 7T.

Cited by 34 publications

References 20 publications

Comparing signal‐to‐noise ratio for prostate imaging at 7T and 3T

Comparing signal‐to‐noise ratio for prostate imaging at 7T and 3T

Novel methods for mapping the cavernous nerves during radical prostatectomy

Analysis of an Integrated 8-Channel Tx/Rx Body Array for Use as a Body Coil in 7-Tesla MRI

Contact Info

Product

Resources

About