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"This book presents a comprehensive review of the recent developments in fast L1-norm regularization-based compressed sensing (CS) magnetic resonance image reconstruction algorithms. Compressed sensing magnetic resonance imaging (CS-MRI) is able to reduce the scan time of MRI considerably as it is possible to reconstruct MR images from only a few measurements in the k-space; far below the requirements of the Nyquist sampling rate. L1-norm-based regularization problems can be solved efficiently using the state-of-the-art convex optimization techniques, which in general outperform the greedy techniques in terms of quality of reconstructions. Recently, fast convex optimization based reconstruction algorithms have been developed which are also able to achieve the benchmarks for the use of CS-MRI in clinical practice. This book enables graduate students, researchers, and medical practitioners working in the field of medical image processing, particularly in MRI to understand the need for the CS in MRI, and thereby how it could revolutionize the soft tissue imaging to benefit healthcare technology without making major changes in the existing scanner hardware. It would be particularly useful for researchers who have just entered into the exciting field of CS-MRI and would like to quickly go through the developments to date without diving into the detailed mathematical analysis. Finally, it also discusses recent trends and future research directions for implementation of CS-MRI in clinical practice, particularly in Bio and Neuro-informatics applications."

"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 "

"TUJUAN. Mengetahui akurasi MRI 0,5T dalam mendeteksi ruptur meniskus.BAHAN DAN CARA. Selama kurun waktu 6 bulan (Oktober 2004 sampai dengan Maret 2005) dilakukan pemeriksaan MRI terhadap 19 pasien (20 lutut) dengan klinis ruptur meniskus. Pemeriksaan MRI menggunakan MRI 0,5T superkondukting magnet, Bruker Tomikom, buatan Perancis tahun 2000 dan closely coupled extremity coil dengan teknik konvensional spin-echo T1W1 dan T2WI potongan sagital dan koronal. Dua kriteria MRI dalam mendiagnosis ruptur meniskus adalah adanya signal hiperintens intrameniskus pada T1W1 dan T2W1 yang dapat meluas ke permukaan sendi, ditemukannya morfologi meniskus yang abnormal seperti adanya perubahan kontur atau deformitas fokal meniskus. Untuk mempertajam diagnosis digunakan sistem penderajatan meniskus berdasarkan signal intrameniskus. HasiI pemeriksaan MRI dibandingkan dengan temuan artroskopi sebagai baku emas.HASIL. Sensitivitas, spesifisitas MRI 0,5T dalam mendeteksi ruptur meniskus adalah 84,4% dan 85,7% dengan akurasi 84,6%. Terdapat kesesuaian yang baik antara MRI 0,5T dengan artroskopi (k-D,573)KESIMPULAN. MRI 0,5T merupakan modalitas pencitraan non invasif yang mempunyai sensitivitas dan akurasi yang tinggi yang dapat digunakan untuk mendiagnosis adanya ruptur meniskus.Kata kunci : Ruptur meniskus, MRI, artroskopi.

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OBJECTIVE The purpose of this study was to evaluate the accuracy of MR imaging 0,5T in detecting meniscal tears.

MATERIALS AND METHOD& During an 6 months period (October 2004 until March 2005), 19 patients (20 knees) who had meniscal tears identified at physical examinations underwent MR imaging examinations. MR imaging was performed with a 0,5T (superconducting; Bruker Tomikom, France, 2000) and a closely coupled extremity coil, conventional spin-echo pulse sequences were used in sagital and coronal planes TI and T2 weighted images. Two MR imaging criteria to established the diagnose of meniscal tears were increased internal signal intensity in the meniscus on TI and T2-weighted images, abnormal morphology of the meniscus such as contour or focal deformities of the meniscus. To increase the accuracy of MR imaging, meniscal were grading according to the character of the intrameniscal MR imaging signal. MR imaging finding was compared with arthroscopic results as the standard of reference.

RESULTS. Sensitivity, specificity and accuracy MR imaging 0,5T for detecting meniscal tears were 84,4%, 85,7% and 84,6%. There is good correlation of MR imaging and arthroscopic findings (kappa = 0,573).

CONCLUSION. MR imaging is a non-invasive modality with high sensitivity and accuracy which can used in detecting meniscal tears.

Key wards : Meniscal tears, MR Imaging, arthroscopic."

"Tesis ini membahas tentang analisis dari perancangan divais dioda tunnel dari bahan silikon yang dipabrikasikan dengan menggunakan teknologi planar. Pabrikasi divais disesuaikan dengan teknologi peralatan dan bahan yang tersedia pada Laboratorium Mikroelektronika Puslitbang TELKOKA LIPI Bandung sebagai tempat proses pembuatan. Dalam tesis ini dirancang 3 divais dioda tunnel, dengan berbagai konsetrasi impurity lapisan tipe n+, tetapi bentuk dan ukuran geometrinya sama. Ketiga rancangan tersebut disimulasikan dengan program perangkat lunak SPICES2B, MATLAB dan UIHKCAD untuk memperoleh kurva karakteristik I-V dan hubungan antara konsentrasi impurity bahan dengan unjuk kerja untuk sinyal kecil. Unjuk kerja tersebut meliputi figure of merit, daya maksimum dan efisiensi. Ketiga rancangan dipabrikasi menggunakan teknologi difusi planar, parameter proses yang dipakai dari basil simulasi program perangkat lunak SSUPREM. Hasil simulasi menunjukkan suatu karakteristik divais yang apabila konsentrasi impurity pada bahan tipe n+ (HD) dinaikkan, maka performasi dari dioda tunnel meningkat. Setelah dipabrikasi dan diukur, divais telah menunjukkan fenomena dioda tunnel."

"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."

"Recent advances in MR technology permit the application of diffusion MRI outside of the brain. In this book, the authors present cases drawn from daily clinical practice to illustrate the role of diffusion sequences, along with other morphological and functional MRI information, in the work-up of a variety of frequently encountered oncological and non-oncological diseases. Breast, musculoskeletal, whole-body, and other applications are covered in detail, with careful explanation of the pros and cons of diffusion MRI in each circumstance. Quantification and post-processing are discussed, and advice is provided on how to acquire state of the art images, and avoid artifacts, when using 1.5- and 3-T magnets. Applications likely to emerge in the near future, such as for screening, are also reviewed. The practical approach adopted by the authors, combined with the wealth of high-quality illustrations."

"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."