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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.

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

ABSTRAK
Latar Belakang: Disfungsi sistolik ventrikel kiri memiliki prognosis yang buruk dan sekitar 60% dapat asimptomatik. Penilaian kondisi disfungsi sistolik ventrikel kiri ini dapat diketahui dengan mengukur fraksi ejeksi ventrikel kiri (leftventricular fraction ejection/LVEF) dengan menggunakan pemeriksaan cardiac magnetic resonance (CMR), sedangkan cardiothoracic ratio (CTR) memiliki sensitivitas 86% untuk mendeteksi penurunan fraksi ejeksi (< 50%).Tujuan: Mengetahui adakah hubungan korelasi CTR dengan LVEF pada pasien gagal jantung disfungsi sistolik ventrikel kiri. Metode: Menggunakan desain korelatif studi potong lintang (cross sectional) dan retrospektif dengan minimal sampel 47 pasien. Analisis data menggunakan uji korelasi dan regresi. Hasil: Didapatkan korelasi negatif antara CTR dan LVEF dengan r = -0,20 dan  p = 0,170. Kesimpulan: Terdapat hubungan yang tidak bermakna antara CTR dan LVEF.

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ABSTRACT
Background: Left ventricular systolic dysfunction has a poor prognosis and about 60% can be asymptomatic. Assessment of left ventricular systolic dysfunction condition can be determined by measuring left ventricular fraction ejection (LVEF) by cardiac magnetic resonance (CMR) examination, while cardiothoracic ratio (CTR) has 86% sensitivity to detect decreased ejection fraction (< 50%). Purpose: To knowing correlation relationship of CTR with LVEF in patients with heart failure left ventricular systolic dysfunction. Methods: Using correlative design of cross sectional and retrospective studies with a minimum sample of 47 patients. Data analysis using correlation and regression test. Result: There was a negative correlation relationship between CTR and LVEF with r = -0.20 and p = 0.170. Conclutions: Correlations with no significans between CTR and LVEF.

Pesawat angiografi rotasi 3 dimensi digunakan dalam radiologi intervensi, kardiologi intervensi dan bedah invasif minimal yang dapat memvisualisasikan pembuluh darah, dan mengevaluasi anatomi tubuh yang lebih rumit dengan dosis radiasi yang lebih besar dibandingkan generasi sebelumnya. Oleh karena itu, perlu dilakukan perhitungan estimasi dosis radiasi yang masuk ke dalam tubuh pasien yang dibandingkan dengan dosis ambang yang dapat diterima. Penelitian dilakukan dengan menggunakan phantom rando jenis wanita di dua instalasi cathlab dengan jenis pesawat yang berbeda. Pengukuran dosis dilakukan dengan menggunakan TLD pada mata, tiroid, spinal cord, payudara dan gonad pada mode preset yang berbeda untuk kepala dan abdomen. Hasil penelitian menunjukkan pada pesawat 1, dosis yang diterima untuk pengukuran kepala pada mode 5sDR Head berkisar antara 1,17 mGy-3,68 mGy dan pada mode 5sDR Head Care berkisar antara 0,58 mGy-1,15 mGy. Sedangkan untuk pengukuran abdomen pada mode 5sDR Body dosis yang diterima adalah berkisar antara 0,50 mGy-0,85 mGy dan pada mode 5sDR Body Care berkisar antara 0,55 mGy-0,79 mGy. Pada pesawat 2, dosis yang diterima untuk pengukuran kepala pada mode Carotid Prop Scan berkisar antara 2,20 mGy-3.71 mGy dan mode Carotid Roll Scan berkisar antara 2,02 mGy-4,59 mGy. Sedangkan dosis yang diterima untuk pengukuran abdomen pada mode Abdomen Prop Scan berkisar antara 0,44 mGy-2,34 mGy dan pada mode Abdomen Roll Scan berkisar antara 0,43 mGy-1,30 mGy. Kesimpulan dari penelitian ini adalah semua mode preset tidak memberikan dosis yang mendekati dosis ambang untuk setiap titik pengukuran.

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Three dimensional Rotational Angiography 3DRA is mostly used in interventional radiology, interventional cardiology, and minimal invansive surgery to visualize blood vessels, and more complicated anatomy with more visual capacity than the previous generation. The rotating nature of image acquisition with suspected high radiation dose requires dose estimation. This study was aimed to measure radiation dose in 3DRA and compare it to the thresholds for deterministic risks. Measurement using TLDs were carried out on female Rando phantom in two angiography suites with different device types, with the organ of interest being eyes, thyroid, spinal cord, breast and gonad. Different preset modes for head and abdomen were employed for comparison. The result for device 1 showed that dose on 5sDR Head mode ranged from 1,17 mGy 3.68 mGy and in 5sDR Head Care mode ranged from 0,58 mGy 1,15 mGy while the measured dose on the body in 5sDR Body mode ranged from 0,50 mGy 0,85 mGy and in 5sDR Body Care mode ranged from 0,55 mGy 0.79 mGy. On device 2, the result showed the measured dose on the head in carotid prop scan mode ranged from 2,20 mGy 3.71 mGy and in carotid roll scan mode ranged from 2,02 mGy 4,59 mGy while the measured dose on the body in abdomen prop scan mode ranged from 0,44 mGy 2,34 mGy and in abdomen roll scan mode ranged from 0,43 mGy 1,30 mGy. The study presents that all preset modes do not deliver near threshold doses for each measurement point.

Comprehensive guide to diagnosis and management of neurological infectious diseases using MRI. Begins with introduction to tropical diseases of the central nervous system, and their epidemiology, then technique of MRI, and its use for infectious and noninfectious conditions.

Over the past decade, PET-CT has achieved great success owing to its ability to simultaneously image structure and function, and show how the two are related. More recently, PET-MRI has also been developed, and it represents an exciting novel option that promises to have applications in oncology as well as neurology. The first part of this book discusses the basics of these dual-modality techniques, including the scanners themselves, radiotracers, scan performance, quantitation, and scan interpretation. As a result, the reader will learn how to perform the techniques to maximum benefit. The second part of the book then presents in detail the PET-CT and PET-MRI findings in cancers of the different body systems. The final two chapters address the use of PET/CT in radiotherapy planning and examine areas of controversy. The authors are world-renowned experts from North America, Europe, and Australia, and the lucid text is complemented by numerous high-quality illustrations.

Stem Cell Labeling for Delivery and Tracking Using Noninvasive Imaging provides a comprehensive overview of cell therapy imaging, ranging from the basic biology of cell therapeutic choices to the preclinical and clinical applications of cell therapy. It emphasizes the use of medical imaging for therapeutic delivery/​targeting, cell tracking, and determining therapeutic efficacy. The book first presents background information and insight on the major classes of stem and progenitor cells. It then describes the main imaging modalities and state-of-the-art techniques that are currently employed for stem cell tracking. In the final chapters, leading scholars offer clinical perspectives on existing and potential uses of stem cells as well as the impact of image-guided delivery and tracking in major organ systems. Through clear descriptions and color images, this volume illustrates how noninvasive imaging is used to track stem cells as they repair damaged tissue in the body. With contributions from some of the most prominent preclinical and clinical researchers in the field, the book helps readers to understand the evolving concepts of stem cell labeling and tracking as the field continues to move forward.