scholarly journals Twofold improved tumor-to-brain contrast using a novel T1 relaxation-enhanced steady-state (T1RESS) MRI technique

2020 ◽  
Vol 6 (44) ◽  
pp. eabd1635
Author(s):  
R. Edelman ◽  
N. Leloudas ◽  
J. Pang ◽  
J. Bailes ◽  
R. Merrell ◽  
...  

A technique that provides more accurate cancer detection would be of great value. Toward this end, we developed T1 relaxation-enhanced steady-state (T1RESS), a novel magnetic resonance imaging (MRI) pulse sequence that enables the flexible modulation of T1 weighting and provides the unique feature that intravascular signals can be toggled on and off in contrast-enhanced scans. T1RESS makes it possible to effectively use an MRI technique with improved signal-to-noise ratio efficiency for cancer imaging. In a proof-of-concept study, “dark blood” unbalanced T1RESS provided a twofold improvement in tumor-to-brain contrast compared with standard techniques, whereas balanced T1RESS greatly enhanced vascular detail. In conclusion, T1RESS represents a new MRI technique with substantial potential value for cancer imaging, along with a broad range of other clinical applications.

F1000Research ◽  
2018 ◽  
Vol 7 ◽  
pp. 1337 ◽  
Author(s):  
Matthew R. Tangel ◽  
Ardeshir R. Rastinehad

Many exciting advances in medical imaging have been made in recent years that will alter the way we diagnose, stage, and treat patients with prostate cancer. Multiparametric magnetic resonance imaging (MRI) is emerging as the main modality for prostate cancer imaging. Contrast-enhanced ultrasound and shear wave elastography may be strong alternatives in patients who cannot undergo MRI. Prostate-specific membrane antigen-directed positron emission tomography/computed tomography has proven to be valuable in the primary staging of high-risk disease and for detecting disease in patients with biochemical recurrence. As more studies continue to emerge, it is becoming clear that the standard algorithm for diagnosing and staging prostate cancer will undergo significant changes in the near future.


2017 ◽  
Vol 11 (4) ◽  
pp. 201-205 ◽  
Author(s):  
Takeshi Hara ◽  
Takeshi Ogata ◽  
Hiroko Wada ◽  
Takayuki Yabuki ◽  
Susumu Kanazawa

Introduction: Gadobutrol (Gd-DO3A-butrol) (Gadovist®) is a macrocyclic gadolinium-based contrast agent for magnetic resonance imaging (MRI) formulated at 1.0 mmol Gd/ml. Gadobutrol's higher concentration compared to other contrast agents (0.5 mmol Gd/ml) is associated with higher T1 relaxivity. We examined whether gadobutrol increases the accuracy of prostate cancer detection using dynamic contrast-enhanced MRI. Materials and Methods: Multiparametric MRI was performed in 379 patients: 94 patients received 1 M gadobutrol while 285 randomly received equivalent doses of 0.5 M gadoterate meglumine or gadopentetate dimeglumine. MRI images were retrospectively and blindly assessed for the presence of cancer by comparing them with prostate biopsy findings. Results: The specificity and accuracy were significantly higher with 1 M gadobutrol than 0.5 M of the other contrast agents. There were no significant differences in the sensitivity, or positive and negative predictive values. Conclusion: Multiparametric MRI using 1 M gadobutrol may improve the accuracy of prostate cancer detection.


2016 ◽  
Vol 7s1 ◽  
pp. BECB.S34255 ◽  
Author(s):  
Saradwata Sarkar ◽  
Sudipta Das

Imaging is playing an increasingly important role in the detection of prostate cancer (PCa). This review summarizes the key imaging modalities–multiparametric ultrasound (US), multiparametric magnetic resonance imaging (MRI), MRI-US fusion imaging, and positron emission tomography (PET) imaging–-used in the diagnosis and localization of PCa. Emphasis is laid on the biological and functional characteristics of tumors that rationalize the use of a specific imaging technique. Changes to anatomical architecture of tissue can be detected by anatomical grayscale US and T2-weighted MRI. Tumors are known to progress through angiogenesis–-a fact exploited by Doppler and contrast-enhanced US and dynamic contrast-enhanced MRI. The increased cellular density of tumors is targeted by elastography and diffusion-weighted MRI. PET imaging employs several different radionuclides to target the metabolic and cellular activities during tumor growth. Results from studies using these various imaging techniques are discussed and compared.


2018 ◽  
pp. 73-78
Author(s):  
Yu. V. Morozov ◽  
M. A. Rajfeld ◽  
A. A. Spektor

The paper proposes the model of a person seismic signal with noise for the investigation of passive seismic location system characteristics. The known models based on Gabor and Berlage pulses have been analyzed. These models are not able wholly to consider statistical properties of seismic signals. The proposed model is based on almost cyclic character of seismic signals, Gauss character of fluctuations inside a pulse, random amplitude change from pulse to pulse and relatively small fluctuation of separate pulses positions. The simulation procedure consists of passing the white noise through a linear generating filter with characteristics formed by real steps of a person, and the primary pulse sequence modulation by Gauss functions. The model permits to control the signal-to-noise ratio after its reduction to unity and to vary pulse shifts with respect to person steps irregularity. It has been shown that the model of a person seismic signal with noise agrees with experimental data.


2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Liming Wang ◽  
Yasumitsu Hirano ◽  
Toshimasa Ishii ◽  
Hiroka Kondo ◽  
Kiyoka Hara ◽  
...  

Abstract Background Mature presacral (retrorectal) teratoma is very rare. We report a case in which a mature retrorectal teratoma in an adult was successfully treated with laparoscopic surgery. Case presentation A 44-year-old woman was diagnosed with a presacral tumor during a physical examination. Endoscopic ultrasonography (EUS) revealed a multilocular cystic lesion; the lesion was on the left side of the posterior rectum and measured approximately 30 mm in diameter on both contrast-enhanced pelvic computed tomography (CT) and magnetic resonance imaging (MRI). The presumptive diagnosis was tailgut cyst. However, the histopathological diagnosis after laparoscopic resection was mature teratoma. It is still difficult to preoperatively diagnose mature retrorectal teratomas. Conclusions Laparoscopic resection of mature retrorectal teratomas is a feasible and promising method that is less invasive and can be adapted without extending the skin incision.


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