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"Renowned for its superb illustrations and highly practical information, the third edition of this classic reference reflects the very latest in state-of-the-art imaging technology. Together with Volumes 2 and 3, this compact and portable book provides a highly specialized navigational tool for clinicians seeking to master the ability to recognize anatomical structures and accurately interpret CT and MR images."

"The idea of using the enormous potential of magnetic resonance imaging (MRI) not only for diagnostic but also for interventional purposes may seem obvious, but it took major efforts by engineers, physicists, and clinicians to come up with dedicated interventional techniques and scanners, and improvements are still ongoing. Since the inception of interventional MRI in the mid-1990s, the numbers of settings, techniques, and clinical applications have increased dramatically. This state of the art book covers all aspects of interventional MRI. The more technical contributions offer an overview of the fundamental ideas and concepts and present the available instrumentation. The richly illustrated clinical contributions, ranging from MRI-guided biopsies to completely MRI-controlled therapies in various body regions, provide detailed information on established and emerging applications and identify future trends and challenges."

"Even as magnetic resonance imaging (MRI) has matured into an invaluable diagnostic tool, it has also become a key experimental tool in biological research, where it demonstrates special sensitivity to a plethora of physiological factors, as well as a capacity for use all the way from cellular suspensions to in vivo human studies. In Magnetic Resonance Imaging: Methods and Biologic Applications, leading experts in the use of MRI from both academia and industry explain its basic principles and demonstrate its power to understand biological processes with numerous cutting-edge applications. To illustrate its capability to reveal exquisite anatomical detail, the authors discuss MRI applications to developmental biology, mouse phenotyping, and fiber architecture. MRI can also provide information about organ and tissue function based on endogenous contrast mechanisms. Examples of brain, kidney, and cardiac function are included, as well as applications to neuro- and tumor pathophysiology. In addition, the volume demonstrates the use of exogenous contrast material in functional assessment of the lung, noninvasive evaluation of tissue pH, the imaging of metabolic activity or gene expression that occur on a molecular level, and cellular labeling using superparamagnetic iron oxide contrast agents. Cutting-edge and user-friendly, Magnetic Resonance Imaging: Methods and Biologic Applications illuminates for biological scientists the basic principles of MRI and shows how it can be used successfully to solve important biological problems."

"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."

"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."

"Astrositoma merupakan salah satu tumor otak primer terbanyak dengan mortalitas yang tinggi. Pemeriksaan MRI dan ADC dapat membantu menentukan derajat astrositoma sebelum dilakukan biopsi histopatologi sehingga edukasi mengenai tatalaksana dan prognosis pasien dapat dilakukan lebih dini. Metode: Penelitian potong lintang ini menggunakan data sekunder MRI kepala pasien dengan histopatologi astrositoma. Penilaian astrositoma dilakukan berdasarkan gambaran MRI menggunakan kriteria Dean dkk dan pengukuran ADC untuk seluruh bagian tumor (Ab) dan bagian tumor padat yang menyangat kontras (Ap) serta beberapa sampel (Ar) pada satu potongan terbesar di ADC map. Analisis data dilakukan untuk mendapatkan nilai diagnostik gambaran MRI dan ADC untuk menentukan derajat astrositoma berdasarkan sensitivitas, spesifisitas, dan kurva receiver operating characteristic (ROC). Hasil: Parameter gambaran astrositoma pada MRI yang bermakna untuk menentukan astrositoma derajat rendah dan tinggi adalah batas, perdarahan, dan heterogenitas. Penggunaan jumlah skoring kriteria Dean dkk pada gambaran astrositoma dengan nilai batas 7 serta penilaian gambaran astrositoma pada MRI untuk menentukan astrositoma derajat rendah dan tinggi memiliki sensitivitas 90,9% dan spesifisitas 87,5%. ADC dengan menggunakan nilai rerata, minimum, dan maksimum pada Ap serta nilai rerata dan minimum pada Ar berbeda bermakna untuk menentukan astrositoma derajat rendah dan tinggi dengan nilai sensitivitas dan spesifisitas masing-masing mencapai 90,9% dan 87,5%. Kesimpulan: MRI dan ADC memiliki sensitivitas dan spesifisitas tinggi untuk menentukan astrositoma derajat rendah dan tinggi.

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Astrocytoma is the most frequent primary brain tumor with high mortality. MRI and ADC could determine astrocytoma grading before histopathological biopsy performed, hence patient education for treatment and prognosis could be established more early.

Method: A cross-sectional research is performed using brain MRI of patients with astrocytoma as histopathological diagnosis. Astrocytoma evaluation using MRI image with Dean et al criteria and ADC measurement for all part of tumor (Ab), single (Ap) and multiple (Ar) solid part of tumor that enhance with contrast administration in one axial section of the largest part of the tumor. Data analysis is performed to obtain diagnostic value of MRI image and ADC to determine astrocytoma grade based on sensitivity, specificity, and receiver operating characteristic (ROC) curve.

Result: MRI image parameters that is significant to determine low and high grade astrocytoma are border, hemorrhage, and heterogeneity. The sum of astrocytoma image scoring of Dean et al criteria with cut-off value of 7 and the evaluation of astrocytoma image in MRI to determine low and high grade astrocytoma has 90,9% sensitivity and 87,5% specificity. ADC, for Ap and Ar, is significant to determine low and high grade astrocytoma with sensitivity up to 90,9% and specificity up to 87,5%.

Conclusion: MRI and ADC has high sensitivity and specificity to determine low and high grade astrocytoma."

"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."