Termal Terapilerin Yönlendirilmesinde Çift Yollu Sekanslar Kullanarak Manyetik Rezonans Termometrisinin Sıcaklık-Gürültü Oranını Artırmak için 1.5T, 3T ve 7T?de Organa Özgü Öneriler

Year 2020, Volume: 6 Issue: 2, 209 - 218, 01.01.2020

Pelin Çiriş

Abstract

Amaç: Termal tedaviler, cerrahi müdahaleye minimal invaziv alternatifler sağlar. Güvenlik ve etkinlikleri, doğru sıcaklık izleme gerektirir. Manyetik rezonans MR termometrisinin sıcaklık/gürültü oranının TNR , çift yollu sekanslarla 3T manyetik alan değerinde dokuya özgü parametreler kullanılarak artırılabileceği daha önce gösterilmiştir. Bu çalışma, daha fazla dokuda 1.5T, 3T ve 7T manyetik alan güçlerinde, doğruluk ve hız artırabilmek için, kapsamlı öneriler sunar.Gereç ve Yöntemler: Çift yollu bir ‘Kararlı-Hal-Serbest-Devinim-Hızlı-Görüntüleme’ FISP -‘ters FISP’ PSIF sekansının TNR’si, daha geleneksel bir çift FISP ile karşılaştırıldı. Analitik çözümler, TNR hesaplamaları ve Monte Carlo simülasyonları ile yazılım doğrulandı. Öneriler, 1.5T ve 3T’de meme glandüler ve yağ dokusu, miyometriyum, endometriyum, serviks, karaciğer, prostat, pankreas, dalak, miyokard, optik sinir ve omurilik; 1.5T, 3T ve 7T’de gri madde, beyaz madde, böbrek medulla ve korteks, iskelet kası, yağ, kıkırdak ve kemik iliği için, geliştirildi.Bulgular: PSIF-FISP kullanımı, TR azaldıkça TNR’yi büyük ölçüde artırırken, sapma-açısı arttıkça ise TNR’yi hafifçe artırmıştır. Özellikle, böbrek, uterus, prostat, dalak, optik sinir ve omurilikte çoğu parametre ayarında ve alan değerinde iyileşme görülmüştür. Ek olarak, karaciğer, pankreas, kıkırdak, iskelet kası, miyokard ve memede yalnızca kısa tekrar-süresi TR ayarlarında iyileşme görülmüştür. Beyinde 1.5T ve 3T’de çoğu parametre ayarlarında iyileşme görülürken, iyileşme 7T’de azalmıştır. Yağ ve kemik iliğinde 1.5T’de çoğu parametre ayarında iyileşme görülürken, iyileşme 3T ve 7T’de azalmıştır. Servikste ise 3T’de çoğu parametre ayarlarında yaygın iyileşme görülürken, 1.5T’de yalnızca kısa TR ayarlarında iyileşme görülmüştür. Sonuç: MR termometrisi TNR ve görüntü elde etme hızı, çift yollu dizinlerle hedef dokuya ve manyetik alan değerine göre seçilen parametreler kullanılarak, önemli ölçüde artırılabilir

Keywords

Termal tedaviler, Manyetik rezonans termometrisi, Proton rezonans frekans kayması, Sıcaklık-gürültü oranı

Organ-Specific Recommendations for Increasing Temperature- To-Noise Ratio of Magnetic Resonance Thermometry Using Dual-Pathway Sequences at 1.5T, 3T, and 7T during Guidance of Thermal Therapies

Abstract

Objective: Thermal therapies provide minimally-invasive alternatives to surgery. Their safety and efficacy require accurate temperature monitoring. Dual-pathway sequences were shown to improve magnetic resonance MR thermometry temperature-to-noise-ratio TNR using tissue specific parameters at 3T. This study provides expanded guidance for increasing accuracy and speed, across a wider range of tissue types at magnetic field strengths 1.5T, 3T and 7T.Material and Methods: TNR of a dual-pathway ‘Fast-Imaging-with-Steady-state-free-Precession’ FISP -‘inverted-FISP’ PSIF sequence was compared to a more conventional dual-FISP. Software was validated against analytical solutions, TNR calculations and Monte Carlo simulations. Recommendations were developed for breast glandular tissue and fat, myometrium, endometrium, cervix, liver, prostate, pancreas, spleen, myocardium, optic nerve and spinal cord at 1.5T and 3T; and for gray matter, white matter, kidney medulla and cortex, skeletal muscle, fat, cartilage, bone marrow at 1.5T, 3T, and 7T.Results: TNR improved using PSIF-FISP: in the kidney, uterus, prostate, spleen, optic nerve and spinal cord at most parameters and fields; in the liver, pancreas, cartilage, skeletal muscle, myocardium, and breast at only short repetition-times TR ; in the brain at 1.5T and 3T across most parameters, but the benefits decreased at 7T; in fat and bone marrow at 1.5T across most parameters, but the benefits decreased at 3T and 7T; and in the cervix at 1.5T at only short TRs, and at 3T with widespread benefits at most parameters. In all cases, PSIF-FISP improved TNR greatly as TR decreased, and slightly as the flip-angle increased.Conclusion: MR thermometry TNR and speed can increase considerably using dual-pathway sequences with parameters selected based on target tissue and magnetic field strength

Keywords

Thermal therapies, Magnetic resonance thermometry, Proton resonance frequency shift, Temperature-to-noise-ratio, Simulation and modeling, ‘Fast-Imaging-with-Steady-state-freePrecession’ (FISP)-‘inverted-FISP’ (PSIF)

References

• Silva D, Sharma M, Juthani R, Meola A, Barnett GH. Magnetic resonance thermometry and laser interstitial thermal therapy for brain tumors. Neurosurg Clin N Am 2017; 28(4):525-33.
• Boone CE, Wojtasiewicz T, Moukheiber E, Butala A, Jordao L, Mills KA, Sair H, Anderson WS. MR-Guided functional neurosurgery: Laser ablation and deep brain stimulation. Top Magn Reson Imaging 2018; 27(3):171-7.
• Zafar A, Quadri SA, Farooqui M, Ortega-Gutierrez S, Hariri OR, Zulfiqar M, Ikram A, Khan MA, Suriya SS, Nunez-Gonzalez JR, Posse S, Mortazavi MM, Yonas H. MRI-Guided high-intensity focused ultrasound as an emerging therapy for stroke: A review. J Neuroimaging 2019; 29(1):5-13.
• Ierardi AM, Savasi V, Angileri SA, Petrillo M, Sbaraini S, Pinto A, Hanozet F, Marconi AM, Carrafiello G. Percutaneous high frequency microwave ablation of uterine fibroids: Systematic review. Biomed Res Int 2018; 2018:2360107.
• Kılıç G, Bildacı T, Boruban M. Anormal uterus kanamasında mikrodalga endometriyal ablasyon (Mea) uygulanan hastalarin vaka serisi. Turkish Journal of Gynecologic Oncology 2006; 9(2):39-45.
• Yang YL, Chen CZ, Zhang XH. Microwave ablation of benign thyroid nodules. Future Oncol 2014; 10(6):1007- 14.
• Matsumoto R, Oshio K, Jolesz FA. Monitoring of laser and freezing-induced ablation in the liver with T1- weighted MR imaging. J Magn Reson Imaging 1992; 2(5):555-62.
• Graham SJ, Bronskill MJ, Henkelman RM. Time and temperature dependence of MR parameters during thermal coagulation of ex vivo rabbit muscle. Magn Reson Med 1998; 39(2):198-203.
• Bazrafshan B, Hübner F, Farshid P, Larson MC, Vogel V, Mäntele W, Vogl TJ. A liver-mimicking MRI phantom for thermal ablation experiments. Medical Physics 2011; 38(5):2674.
• Bottomley PA, Foster TH, Argersinger RE, Pfeifer LM. A review of normal tissue hydrogen NMR relaxation times and relaxation mechanisms from 1-100 MHz: dependence on tissue type, NMR frequency, temperature, species, excision, and age. Med Phys 1984; 11(4):425-48.
• Wright PJ, Mougin OE, Totman JJ, Peters AM, Brookes MJ, Coxon R, Morris PE, Clemence M, Francis ST, Bowtell RW, Gowland PA. Water proton T1 measurements in brain tissue at 7, 3, and 1.5 T using IR- EPI, IR-TSE, and MPRAGE: Results and optimization. MAGMA 2008; 21(1-2):121-30.
• Cox RW, Gowland PA. Measuring T2 and T2’ in the brain at 1.5T, 3T and 7T using a hybrid gradient echo- spin echo sequence and EPI. Toronto: International Society for Magnetic Resonance in Medicine, 2008.
• de Bazelaire CM, G. D, Rofsky NM, Alsop DC. MR imaging relaxation times of abdominal and pelvic tissues measured in vivo at 3.0 T: Preliminary results. Radiology 2004; 230(3):652-9.
• Metzger GJ, Snyder C, Akgun C, Vaughan T, Ugurbil K, Van de Moortele PF. Local B1+ shimming for prostate imaging with transceiver arrays at 7T based on subject- dependent transmit phase measurements. Magn Reson Med 2008; 59(2):396-409.
• Gold GE, Han E, Stainsby J, Wright G, Brittain J, Beaulieu C. Musculoskeletal MRI at 3.0 T: Relaxation times and image contrast. AJR Am J Roentgenol 2004; 183(2):343- 51.
• Jordan CD, Saranathan M, Bangerter NK, Hargreaves BA, Gold GE. Musculoskeletal MRI at 3.0 T and 7.0 T: A comparison of relaxation times and image contrast. Eur J Radiol 2013; 82(5):734-9.
• Rakow-Penner R, Daniel B, Yu H, Sawyer-Glover A, Glover GH. Relaxation times of breast tissue at 1.5T and 3T measured using IDEAL. J Magn Reson Imaging 2006; 23(1):87-91.
• Stanisz GJ, Odrobina EE, Pun J, Escaravage M, Graham SJ, Bronskill MJ, Henkelman RM. T1, T2 relaxation and magnetization transfer in tissue at 3T. Magn Reson Med 2005; 54(3):507-12.