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"This book describes the current status of the very rapidly developing field of high-field MR and examines the possibilities, challenges, and limitations of this fascinating technology. In the initial chapters, the basic technological background is explained in a non-technical way so as to promote understanding of the issues and concepts and avoid overwhelming the reader with excessive detail. Safety issues, methods, and contrast are then carefully considered. The final part of the book examines the diverse applications of high-field MR imaging in radiology, neuroscience, oncology, and other fields, with the aid of numerous high-quality illustrations. All chapters are written by leading experts who have taken great care to illustrate the potential and progress of the field in an informative and accessible manner. The book will appeal to all with a potential interest in the application of high-field MR imaging, including radiologists, neuroscientists, and oncologists."

"The objective of this book is to serve as a practical educational resource for clinical magnetic resonance imaging. The bulk of the text is organized along anatomic lines and discusses disease entities commonly encountered in clinical practice. The focus is illustrating and describing the MR appearances of the most commonly imaged disease entities, covering briefly in each area important points relative to imaging techniques then discussing in depth, the clinical MR interpretation. The breadth of clinical MRI is explored. For each subtopic within an anatomic region, clinical cases serve as the backbone for discussion, the most common pathologies affecting each anatomic region being illustrated. The final chapters discuss specifically contrast media and contrast enhanced MRA, two topics worthy of further description due to their present clinical importance. When relevant to diagnosis or essential for understanding, MR physics is discussed, however the reader is referred separately to Runge et al, The Physics of Clinical MR Taught Through Images 2nd Edition (New York: Thieme; 2009) for further elaboration. It is the goal that upon completing this text, the reader will have an appreciation for the complexity, utility, and versatility of MR in clinical imaging and will possess the knowledge essential for interpretation of basic clinical MR "

"Pada saat ini, teknologi elektromagnetik terapan telah digunakan di berbagai bidang, termasuk di bidang kesehatan. Teknologi ini banyak diaplikasikan untuk melakukan proses analisa suatu penyakit atau bahkan melakukan penyembuhan. Dari banyak kegunaan itu, salah satu aplikasi teknologi elektromagnetik terapan di bidang medis adalah sistem pencitraan penampang tubuh. Dari beberapa instrumen kesehatan yang berfungsi untuk menampilkan pencitraan penampang tubuh, Magnetic Resonance Imaging (MRI) memiliki keunggulan untuk melakukan pencitraan organ-organ lunak. Pengaplikasian teknologi MRI terus berkembang hingga sekarang termasuk teknik penggunaan RF Coil Resonator yang terdapat di sistem MRI.Pada skripsi ini akan dirancang bangun sebuah RF Coil Resonator untuk sistem MRI 3 Tesla agar dapat menghasilkan citra atau penggambaran dari objek yang lebih jelas dan dapat digunakan oleh tenaga medis seperti dokter sebagai acuan untuk menganalisa suatu jaringan lunak yang bermasalah. Penelitian ini merancang sebuah resonator phased array yang terdiri dari 8 elemen yang bekerja pada frekuensi 127,7 MHz. Berdasarkan hasil simulasi, resonator tersebut memiliki keseragaman medan magnet dan nilai Specific Absorption Rate (SAR) dibawah ambang batas aman yaitu 0,195 W/kg. Diharapkan hasil rancangan ini dapat bekerja secara paralel untuk meningkatkan fungsionalitas dan kemampuan sistem MRI yang menghasilkan suatu citra yang lebih baik dan waktu scanning yang lebih cepat dibandingkan dengan resonator konvensional. Resonator phased array coil ini telah difabrikasi dan diukur parameter S-parameter dengan hasil yang sesuai dengan hasil simulasi pada frekuensi kerja 127,67 MHz.

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Currently, applied electromagnetic technology has been used in various fields, including for health sector. This technology is widely adopted for disease diagnosis as well as for treatment. One of several applications in applied electromagnetic technology is imaging system for medical field application. One of medical instruments which are used for body imaging system, that is Magnetic Resonance Imaging (MRI), has the advantage to create an image of soft organ. Application of MRI technology continues to evolve up until now, including the development of RF Coil Resonator techniques for MRI systems.

In this thesis, a RF Resonator Coil for 3 MRI 3 Tesla system is designed in order to produce high-resolution images, so it can be used by medical personnel such as doctors to analyze the soft tissue problems.

In this study, a RF phased array resonator that consists of 8 elements is designed for working at the frequency of 127.7 MHz. According to the simulation results, the resonator has uniform magnetic field and low value of Specific Absorption Rate (SAR) below the safety threshold by 0.195 W / kg.

It is expected that this design is able to operate for parallel operation in order to increase the functionality and capability of the MRI system can produces a better image and a faster scanning time in comparison with the conventional resonator one. The phased array coil resonator has been fabricated and measured, where the Sparameter results agree with the simulation results at the operation frequency 127.67 MHz."

"Pada skripsi ini dirancang sebuah resonator RF Birdcage Coil tanpa lumped circuit untuk aplikasi sistem Magnetic Resonance Imaging (MRI). MRI merupakan teknologi pencitraan tubuh manusia untuk aplikasi diagnosis medis yang bersifat non-invasive dan tidak memiliki pengaruh radiasi foton seperti halnya yang terdapat pada sistem Computed Tomography (CT). MRI memanfaatkan efek kuat medan magnet untuk mensejajarkan susunan inti atom hidrogen (proton) dengan arah medan magnet eksternal. Pada saat yang bersamaan sistem memancarkan RF Pulse ke tubuh pasien kemudian menerima sinyal Magnetic Resonance (MR) untuk rekonstruksi citra penampang tubuh. Pada penilitian ini dirancang suatu resonator RF Birdcage Coil tanpa lumped circuit yang beresonansi di spektrum frekuensi 128 MHz. Secara desain, resonator ini dirancang terdiri atas Leg dan End Rings (ERs) terbuat dari selembar konduktor tembaga tipis yang ditempelkan di kedua sisi akrilik sebagai material substrat untuk memberikan nilai kapasitansi resonator dan sekaligus sebagai pembentuk konfigurasi resonator RF Birdcage Coil. End Rings disusun superposisi untuk membentuk kapasitor secara bergantian. Untuk mendapatkan frekuensi resonansi yang diinginkan, dilakukan tuning dengan cara memperbesar atau memperkecil dimensi plat tembaga End Rings untuk mengubah nilai kapasitansi resonator. Desain resonator dirancang dengan menggunakan perangkat lunak Birdcage Builder untuk menghitung nilai kapasitansi awal dan disimulasikan dengan perangkat lunak berbasis Finite Integration Technique (FIT). Setelah dilakukan validasi dengan cara pengukuran tanpa ada tubuh manusia, resonator dapat beresonansi di frekuensi 128,5 MHz. Pengujian resonator dengan memasukkan bagian tubuh manusia seperti kepala dan tangan, resonator memberikan response perubahan yang sangat kecil pada pergeseran frekuensi berturut-turut 128,8 MHz dan 127,7 MHz untuk kepala dan tangan manusia.

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In this final project the RF Birdcage Coil resonator is designed without using lumped circuit for application of Magnetic Resonance Imaging (MRI) system. MRI is a scanning technology of human body tissues to medical diagnosis application which generally is non-invasive and doesn’t has the impact of photon like another system such as Computed Tomography (CT). It utilizes the effect of magnetic field strength to aligns proton with external magnetic field and transmits the RF Pulse to the human body then recieves the Magnetic Resonance (MR) signal for image reconstruction simultaneously.

In this research the RF Birdcage Coil resonator is designed without using lumped circuit and it can resonance in 128 MHz. This resonator has the Leg and End Rings which is made from copper foil and attached to the inner and outer of acrylic as a substrat material to produce the capacitance of the resonator and also as a shaper of the RF Birdcage Coil’s configuration. The End Rings arrange superposition to create the capacitance respectively. To get desired resonance frequency it should be tuned by make dimension foil of End Rings bigger or smaller to change the capacitance.

Birdcage Builder as a software which used to design the beginning form of the resonator and count the first value of capacitance then simulated in software based on Finite Integration Technique. After validation with measurement without human body the resonator can resonance in 128,5 MHz. Measurement with import body parts such as head and hand into resonator give the smallest change in 128,8 MHz and 127,7 MHz for human head and hand respectively."

"Magnetic resonance imaging selanjutnya disebut MRI merupakan peralatan radiologi diagnostik yang tidak mengandung radiasi pengion. Hal tersebut tidak berarti menjadikan alat ini bebas dari potensi bahaya. Penelitian ini ditujukan untuk mendapatkan deskripsi, menganalisa dan menilai penerapan keselamatan lingkungan pada fasilitas MRI 1.5T di wilayah DKI Jakarta. Penelitian didesain dengan metode campuran dengan tehnik purposive sampling. Dilaksanakan pada 4 fasilitas MRI 1.5T di wilayah DKI Jakarta dengan jumlah responden sebanyak 25 (dua puluh lima) orang radiografer yang bertugas di pelayanan MRI. Data kuantitatif diuji dengan menggunakan uji statistik nonparametrik yaitu Cochran’s Q dan Kruskalwalis. Nilai Cochran’s Q hitung>Chi square tabel (66.495>36.415) sehingga H0 ditolak atau terdapat perbedaan pemahaman radiografer. Uji statistik kruskalwalis menunjukkan nilai mean rank antar rumah sakit sumber data bervariasi. Data kualitatif terkait ketersediaan perangkat keselamatan menunjukkan standar American Collage of Radiology (ACR) lebih aplikatif dibandingkan standar Keputusan Menteri Kesehatan (KMK) RI No. 410/MENKES/SK/III/2010 tentang standar pelayanan radiologi diagnostik di sarana pelayanan kesehatan. Keempat rumah sakit sumber data telah memenuhi standar ACR sedangkan standar KMK 410/2010 hanya dapat dipenuhi oleh sebagian. Kepatuhan petugas dalam praktek aman penanganan pasien mandiri di empat rumah sakit sumber data telah memenuhi standar ACR dengan nilai bervariasi.

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Magnetic resonance imaging is hereinafter referred to MRI as diagnostic radiology equipment that contains no ionizing radiation. That does not mean to make this tool is free of potential hazards. This study aimed to get a description, analyze and assess the implementation of environmental safety at 1.5T MRI facility in Jakarta. The research is designed with a mix method with purposive sampling technique. Held on 4 (four) 1.5T MRI facilities in Jakarta. The number of respondents as many as 25 (twenty five) radiographers who served in MRI services. The quantitative data were tested using nonparametric statistical test that Cochran's Q and Kruskalwalis . Cochran's Q value count > Chi square table (66 495> 36 415) so that H0 is rejected or there is a difference of understanding radiographer. Kruskalwalis statistical test shows the mean rank among hospitals varied data sources. The qualitative data related to the availability of safety devices demonstrate the American Collage Of Radiology (ACR) standards more applicable than Keputusan Menteri Kesehatan (KMK) RI No. 410/MENKES/SK/III/2010 standard. The fourth hospital data sources meet the standard ACR while KMK 410/2010 standard can only be met by the majority. Compliance officers in the safe practice of self-management of patients in four hospitals have a data source meets ACR standards with varying grades."

"Pada kasus lumbal spinal stenosis, penentuan terapi dibedakan menjadi konservatif termasuk medikamentosa dan rehabilitasi medik dan pembedahan. Secara general, pembedahan dilakukan pada pasien yang tidak mengalami perbaikan klinis setelah menjalani terapi konservatif. Tesis ini membahas perbedaan gambarandegenerative lumbar spinal stenosis berupa pengukuran faktor determinan menggunakan MRI lumbosakral pada pasien yang menjalani pembedahan kelompok uji dan konservatif kontrol. Pengamatan perubahan radiologis yang akurat akan membantu klinisi memperkirakan terapi yang sesuai untuk pasien secara lebih dini dan efektif. Sebagai hasil, secara bivariat, faktor determinan yang bermakna adalah stenosis kanalis lumbal L3-4; stenosis recessus lateral L4-5 dan L5-S1; stenosis foraminal L3-4 bilateral dan L5-S1 kiri; hernia nukelus pulposus L3-4 dan L5-S1, hipertrofi ligamentum flavum L3-4 dan degenerasi sendi facet L4- 5 kanan. Dengan analisa multivariat, didapatkan hanya hernia nukelus pulposus L3- 4 dan L5-S1 saja yang menentukan keputusan operasi.

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In degenerative lumbal spinal stenosis, choice of treatment divide into conservative with medication and rehabilitation included and surgical. Generally, surgery to patient perform when there is no improvement in clinical examination after adequate conservative treatment. In this thesis, we describe difference in determinant factors seen with MR study to patients with lumbar spinal stenosis who had surgical treatment case group and conservative treatment control group. Carefull observation in radiologic changes will help clinician to predict patient outcome and decide adequate treatment. As results, using bivariate analysis, we conclude that there are significantly differences in lumbal canal stenosis at L3 4 level lateral recessus stenosis at L4 5 and L5 S1 level, foraminal stenosis at L3 4 bilaterally and at left side of L5 S1 level hernia nucleus pulposus at L3 4 and L5 S1 level flavum ligament hypertrophy at L3 4 level and facet joint degeneration at right side of L4 5 level. Meanwhile, using multivariate analysis, only hernia nucleus pulposus of L3 4 and L5 S1 level bring decision to surgery."

"Tujuan: Penelitian ini dilakukan untuk mengetahui korelasi perubahan nilai ADC pada DWMRI dengan perubahan ukuran tumor pasca kemoterapi neoajuvan kanker payudara dalam menilai respons kemoterapi neoajuvan. Metode: Penelitian studi deskriptif analitik dari data sekunder MRI pasien kanker payudara yang mendapat kemoterapi neoajuvan serta menjalankan pemeriksaan MRI. Pemeriksaan MRI dilakukan sebelum pasien mendapat kemoterapi neoajuvan, setelah pasien mendapat kemoterapi neoajuvan siklus pertama dan siklus ketiga. Pengukuran ukuran tumor dilakukan sesuai standar RECIST, sedangkan nilai ADC diperoleh pada nilai b800s/mm2. Hasil dan diskusi: Dilakukan analisis bivariat dengan menggunakan korelasi Pearson untuk melihat korelasi perubahan nilai ADC kedua terhadap nilai ADC pertama dengan perubahan ukuran tumor pada pemeriksaan MRI ketiga terhadap pemeriksaan MRI pertama. Sebanyak 17 pasien penelitian dengan usia antara 40 tahun sampai 65 tahun dan ukuran tumor antara 5,41 cm sampai 13,41 cm. Terdapat 16 pasien yang mengalami peningkatan nilai ADC dan 1 pasien yang mengalami penurunan nilai ADC setelah pemberian kemoterapi neoajuvan siklus pertama. Sebanyak 17 pasien mengalami pengurangan ukuran tumor setelah kemoterapi neoajuvan siklus ketiga. Berdasarkan standar RECIST diperoleh sebanyak 7 pasien dengan pengurangan ukuran tumor lebih dari 30% (antara 31,55% sampai 56,25%) dan sebanyak 10 pasien dengan pengurangan ukuran tumor kurang dari 30% (antara 7,47% sampai 29,22%). Nilai korelasi yang diperoleh sebesar -0,499. Kesimpulan: Terdapat korelasi yang bermakna antara perubahan nilai ADC pada DWMRI dengan perubahan ukuran tumor sebagai respons kemoterapi neoajuvan kanker payudara dengan kekuatan korelasi yang sedang dan arah negatif.

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Objectives: To determine the correlation of changes in ADC values in DWMRI with changes in tumor size after neoadjuvant chemotherapy in breast cancer to assess neoadjuvant chemotherapy response.

Methods: Analytical descriptive study using secondary data from MRI of breast cancer patients receiving neoadjuvant chemotherapy as well as running an MRI. MRI examination performed before neoadjuvant chemotherapy, after received first cycle neoadjuvant chemotherapy and third cycle. Tumor size measurements carried out according to standard RECIST, whereas the ADC values obtained in the b800s/mm2. Bivariate analysis using Pearson correlation was conducted to determine the correlation of changes in the value of the second ADC to first ADC and changes of the tumor size on the third MRI to the first MRI examination.

Result and discussion: A total of 17 study patients, 40 years to 65 years old, tumor size between 5.41 cm to 13.41 cm. 16 patients experienced an increase in ADC values while 1 patient had decreased ADC values after the first cycle of neoadjuvant chemotherapy. Tumor size in all patients decreased after three cycles of neoadjuvant chemotherapy. Based on RECIST standards, 7 patients showed tumor size reduction of more than 30% (between 31.55% to 56.25%) and tumor size in 10 patients was reduced less than 30% (between 7.47% to 29.22% ). Correlation value of -0.499 obtained.

Conclusions: There is a significant moderate and negative correlation between in ADC value changes in DWMRI with tumor size changes in response to neoadjuvant chemotherapy."

"Magnetic Resonance Imaging (MRI) saat ini sedang banyak digunakan sebagai image guiding dalam perencanaan radiosurgery dan radioterapi. Modalitas pencitraan ini dapat menampilkan karakteristik fisis jaringan dengan detail luar biasa, terutama pada otak. Namun seperti yang telah diketahui, distorsi geometri terjadi pada citra MRI. Distorsi ini menimbulkan masalah di beberapa aplikasi MRI, salah satunya lokalisasi pada Gamma Knife Stereotactic Radiosurgery (GKSRS). Oleh karena itu, pengukuran serta koreksi distorsi geometri pada citra MRI perlu dilaksanakan. Dalam penelitian ini, sebuah fantom desain khusus dikembangkan untuk mengukur tidak hanya distorsi geometri citra MRI, namun juga uniformitas dan resolusi spasial kontras tinggi. Penelitian menggunakan tiga variasi, meliputi variasi protokol pemindaian, frame, dan larutan pengisi. Protokol pemindaian yang digunakan adalah T1-Bravo dan T2-Fiesta. Fantom dengan dan tanpa Leksell stereotactic frame dipindai menggunakan 1,5 T MRI GE Optima MR450w. Fantom diisi dengan tiga variasi larutan yaitu aquades (H2O) serta CuSO4.5H2O dengan konsentrasi 2 mM dan 5 mM. Dari hasil analisis data penelitian dapat ditarik beberapa kesimpulan bahwa fantom desain khusus yang dikembangkan dapat digunakan untuk mengukur distorsi geometri, uniformitas, serta resolusi spasial kontras tinggi citra MRI. Citra MRI yang dihasilkan oleh protokol pemindaian T1-Bravo memiliki distorsi geometri dan resolusi spasial lebih rendah namun uniformitas lebih tinggi dibandingkan citra yang dihasilkan oleh protokol T2-Fiesta. Keberadaan Leksell stereotactic frame ketika proses pemindaian meningkatkan distorsi geometri dan mengurangi uniformitas citra. Selain itu, larutan yang paling sesuai digunakan sebagai pengisi fantom desain khusus adalah larutan CuSO4.5H2O dengan konsentrasi 5 mM.

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Magnetic Resonance Imaging (MRI) is increasingly being used for purposes of radiosurgery and radiotherapy planning. This imaging modality can explore the physical properties of tissue with great details, especially for imaging of the brain. However, the geometric distortion is reasonably occurred and can make significant differences in certain MR application such as, for example, stereotactic localization in Gamma Knife. Therefore, the geometric distortion measurement and correction should be applied.

In this study, an MRI in-house phantom was developed to measure not only geometric distortion, but also uniformity and high contrast spatial resolution of MR image. This study used three variations, including scanning protocol, frame, and phantom filler. There were two scanning protocols applied in this study, they were T1-Bravo and T2-Fiesta. The phantom attached with Leksell stereotactic frame was scanned using 1.5 T MRI GE Healthcare. Phantom was filled with three kinds of solution, they were pure water (H2O), CuSO4.5H2O 2 mM and 5 mM solution.

The study results showed that the in-house or special design phantom can be used to measure geometric distortion, uniformity, and high contrast spatial resolution of MR image. T1-Bravo image had lower geometric distortion and spatial resolution but higher uniformity than T2-Fiesta. Leksell stereotactic frame can increase the magnitude of geometric distortion and decrease the uniformity of MR image. Moreover, the most suitable solution for phantom filler is CuSO4.5H2O 5 mM."

"Latar belakang dan tujuan: Keganasan berhubungan erat dengan keadaan hiperselularitas dan hipervaskularisasi jaringan. Magnetic resonance imagingdiffusion weighted imaging-apparent diffusion coefficient (MRI DWIADC) merupakan biomarker cancer imaging. Mengetahui tingkat kesesuaian antara nilai ADC dengan kontras gadolinium dapat menjadi informasi tambahan dan pemeriksaan alternatif dalam memprediksi keganasan lesi muskuloskletal. Metode: Penelitian prospektif desain potong lintang pada 50 pasien dengan lesi primer muskuloskeletal regio ekstremitas, yang menjalani pemeriksaan MRI muskuloskeletal sekuens DWI-ADC dan pemberian kontrs gadolinium di RSUPN-CM dalam rentang waktu Oktober 2015-Februari 2016. Dilakukan penilaianrerata nilai minimum ADC, serta menghitung akurasi pada kasus-kasus yang dilakukan pemeriksaan histopatologi. Hasil: Dari total 50 subjek penelitian, dengan analisa uji Kappa didapatkan tingkat kesesuaian yang baik (R = 0,592) antara nilai ADC dengan kontras gadolinium dalam memprediksi keganasan lesi muskuloskeletal, dan tidak ada perbedaan hasil yang signifikan diantara kedua metode tersebut(p = 0,754). Selain itu didapatkan sensitivitas nilai ADC (81%) hampir menyerupai kontras gadolinium (90,5%), dan spesifisitas ADC (60%) lebih rendah dibandingkan kontras gadolinium (90%) pada 31 subjek yang dilakukan pemeriksaan histopatologi. Kesimpulan: Terdapat tingkat kesesuaian yang baik antara nilai ADC dengan kontras gadolinium dalam memprediksi keganasan lesi muskuloskeletal, sehingga nilai ADC dapat menjadi informasi tambahan dan modalitas alternatif, terutama pada pasien dengan keterbatasan penggunaan kontras gadolinium.

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Background and purpose: Malignancy is closely linked with the state of hiperselularity and hypervascularization tissues. Magnetic resonance imaging diffusion weighted imaging-apparent diffusion coefficient (ADC DWI-MRI) is biomarker cancer imaging. Knowing the suitability ADC and gadolinium can become an additional information and an alternative method in predicting malignancy musculoskeletal lesions.

Methods: A prospective cross-sectional study design with 50 patients with diagnostic primary extremity muscosceletal lesions who underwent an MRI examination extremity musculoskeletal region using DWI-ADC sequences and gadolinium at RSUPN-CM in October 2015 ? February 2016. The mean minimum ADC exercise is carried out and the accuracy based on histopatology examination cases is calculated.

Results: From 50 subjects been examined with Kappa Test Analysis, it shows good fit result (R = 0.592) between ADC and gadolinium contrast in predicting malignancy musculoskeletal lesions and no significant difference between the two methods (p = 0.754). Also, it is shows that the sensitivity of ADC (81%) is close to gadolinium contrast (90.5%) and the specifity of ADC (60%)is lower than gadolinium contrast (90%) for the 31 subjects who underwent histopathological examination.

Conclusions: Because of good suitability between ADC and gadolinium contrast in predicting malignancy musculoskeletal lesions, ADC could become an additional information and an altenaltive of modality especially to the patient with gadolimium contrast limitation."

"MRI Handbook presents a concise review of the physical principles underlying magnetic resonance imaging (MRI), explaining MR physics, patient positioning, and protocols in an easy-to-read format. The first five chapters of the book introduce the reader to the basics of MR imaging, including the relaxation concept, MR pulse sequences, and MR imaging parameters and options. The second part of the book (chapters 6-11) uses extensive illustrations, images, and protocol tables to explain tips and tricks to achieve optimal MR image quality while ensuring patient safety. Individual chapters are devoted to each major anatomic region, including the central nervous, musculoskeletal, and cardiovascular systems. By using annotated MR images and examples of patient positions used during scanning correlated with sample protocols and parameters."