Susceptibility Weighted Imaging in MRI: Basic Concepts and Clinical Applications

Description

MRI Susceptibility Weighted Imaging discusses the promising new MRI technique called Susceptibility Weighted Imaging (SWI), a powerful tool for the diagnosis and treatment of acute stroke, allowing earlier detection of acute stroke hemorrhage and easier detection of microbleeds in acute ischemia. The book is edited by the originators of SWI and features contributions from the top leaders in the science. Presenting an even balance between technical/scientific aspects of the modality and clinical application, this book includes over 100 super high-quality radiographic images and 100 additional graphics and tables. Susceptibility Weighted Imaging in MRI Susceptibility Weighted Imaging in MRI Basic Concepts and Clinical Applications E. Mark Haacke J € urgen R. Reichenbach Contents Preface Contributors Part I Basic Concepts Introduction to Susceptibility Weighted Imaging Magnetic Susceptibility B ¼ m 0 ð H þ M Þ v ¼ g B ð 2 : 2 Þ B ¼ m 0 ð 1 þ x Þ H or B ¼ ð 2 : 4 Þ v ð x Þ ¼ g ð B 0 þ G x x Þ ð 2 : 6 Þ B ð x Þ ¼ B 0 þ D B ð x Þ þ G x x ð 2 : 7 Þ v ð x Þ ¼ g ð B 0 þ D B ð x Þ þ G x x Þ v ð x Þ ¼ g B 0 þ G x x þ ð 2 : 9 Þ v ð x 0 Þ ¼ g ð B 0 þ G x x 0 Þ D v ¼ g ð d B o Þ w ¼ g D B t w / ð Hct ð 1 Y Þ 2 : 62 10 6 Þ Gradient Echo Imaging k x ¼ 2 p G x t 0 t T acq = 2 ð 3 : 1 Þ w ð x ; t Þ ¼ 2 p k x x ¼ g G x x t 0 t T ac 2 p G x T acq = 2 þ w ð x ; t Þ ¼ g G x x ð t TE Þ j t TE j T acq = 2 ð 3 : 4 k x ¼ g G x T acq = 2 k x ¼ 2 p G x t T acq = 2 ð 3 : 5 Þ ð 3 : 6 Þ α φ TE 3 TE 1 G R ADC 2 p G R D t ¼ ð 3 : 7 Þ ð 3 : 8 Þ 2 p D G S t S ¼ ð 3 : 9 Þ M ? ð t Þ ¼ M 0 e t = T * 2 M ? ¼ M 0 sin a w ¼ g D B TE ¼ g D x B 0 TE w ¼ g G x v t 2 Phase and Its Relationship to Imaging Parameters and Susceptibility w t ð Þ ¼ v t þ w 0 x þ j r j sin w ^ y w t ð Þ ¼ v t ð 4 : 1 Þ ð 4 : 2 Þ r ¼ r x þ r y ¼ j r j cos w ^ ð 4 : 4 Þ þ y 2 p ð Þ ð 4 : 5 Þ ð 4 : 6 Þ ð 4 : 7 Þ w r ; t ð Þ ¼ g B 0 B ð r ; t Þ ð Þ t ¼ g D B r ; t ð Þ t ð 4 : 8 Þ w r ð Þ ¼ g D B r ð Þ TE ð 4 : 9 Þ D w ¼ g D B TE D w ¼ g D B vt TE g D x v t B 0 TE ð Þ e i w 1 r ð Þ ¼ r 1m r ð Þ e i g D B r ð Þ e i w 2 r ð Þ ¼ r 2m r ð Þ e i g D B r ð Þ e e = T 2 r ð Þ ) ð Þ ¼ e i g e D B r ð Þ e i w p p r ð Þ ð Þ e i w q q r ð Þ ð Þ (a) (b) (c) r ð x Þ ¼ f n ð x Þ r ð x Þ f ð x Þ ¼ ½ p þ w ð x Þ f ð x Þ ¼ p w ð x Þ f ð x Þ ¼ p þ w ð x Þ p w ð x Þ f ð x Þ ¼ g w ð x Þ 1 þ exp ½ a ð w ð x Þ b Þ P I ð Þ ¼ p D w ð Þ ¼ F ½ f ð x x 0 Þ ¼ ð ¼ ð ð F ½ f ð x Þ Understanding T * 2 -Related Signal Loss M xy t ð Þ ¼ M xy t ¼ 0 ð Þ e t = T 2 ¼ R 2 þ R 0 2 ð 5 : 2 Þ ð 5 : 3 Þ ð 5 : 4 Þ ð 5 : 5 Þ ð 5 : 7 Þ ð 5 : 8 Þ M sph t ð Þ ¼ ð p ð Þ e i dv sph r ; u dv cyl r ; u ; f ð Þ ¼ g B 0 M C t ð Þ ¼ ð 2 ð Þ e i dv C r ; u ; f ð Þ ¼ M 0 e 0 : 3 l dv net t ð Þ 2 e t = T 2 ð Þ ¼ M 0 e l dv net M t ð Þ ¼ M SE e j t t SE j = T 0 2 Processing Concepts and SWI Filtered Phase Images ð Þ ð Þ þ 2 m r ð Þ p I m r ð Þ ¼ I D r ð Þ e i w r ð Þ ð Þ e i w r ð Þ ¼ j I D r ð Þ j e i w des r ð Þ ð 6 : 4 Þ 1 j w j ð 6 : 6 Þ ð 6 : 7 Þ ð 6 : 8 Þ ð 6 : 9 Þ w ¼ ff w 0 ¼ ff MR Angiography and Venography of the Brain D w g D x B 0 TE exp ½ i dw s ; u ð r Þ ¼ exp ½ i w ð r þ D u Þ i w ð r D u Þ ¼ U D U D u ¼ A ð r þ D u Þ = A ð r þ D u Þ ; U * D u ¼ A * ð r D u Þ = LFG u ð r Þ ¼ dw s ; u ð r Þ = ð g TE 2 j D u jÞ ¼ arg ð U D u U * D LFG 2 x ð r Þ þ LFG 2 y ð r Þ þ LFG 2 z ð r Þ ð 7 : 5 Þ Brain Anatomy with Phase Part II Current Efforts in Clinical Translational Research Using SWI SWI Venographic Anatomy of the Cerebrum Deep Medullary Veins Novel Approaches to Imaging Brain Tumors Traumatic Brain Injury Imaging Cerebral Microbleeds with SWI Imaging Ischemic Stroke and Hemorrhage with SWI Visualizing Deep Medullary Veins with SWI in Newborn and Young Infan Susceptibility Weighted Imaging in Multiple Sclerosis Cerebral Venous Diseases and Occult Intracranial Vascular Malformations Sturge–Weber Syndrome Visualizing the Vessel Wall Using Susceptibility Weighted g D B TE K e TE = T * 2 p K e Imaging Breast Calcification Using SWI Susceptibility Weighted Imaging at Ultrahigh Magnetic Fields h 2 N I I þ 1 ð Þ 3 k T B 0 D w ¼ g D x B 0 TE S ð t Þ ¼ ð W ð r Þ f s ð r Þ r ð r Þ e i y D B ð r Þ t e t = T * 2 ð r Þ Part III Advanced Concepts Improved Contrast in MR Imaging of the Midbrain Using SWI ð Þ ¼ R 2o þ k B 0 Measuring Iron Content with Phase w ¼ g D B TE R * ¼ R * 2 ð Fe Þ ¼ D R * 2 ð Fe Þ (a) (b) (e) (c) (d) (f) (g) ( h ) (a) (c) (d) ( e ) ( f ) (c) (e) ( f ) (a) (b) (c) ( e ) ( f ) (a) (b) (c) (d) ( e ) ( f ) (b) (c) (d) (e) (f) (a) (c) (e) (f) (a) (c) ( e ) ( f ) Validation of Phase Iron Detection with Synchrotron X-Ray Fluorescence ð Þ ½ ¼ 850 D w B 0 T ½ ½ ¼ 217 D w CSF ½ ¼ 434 D w CSF B 0 T ½ Rapid Calculation of Magnetic Field Perturbations from Biological Tiss B ð r Þ ¼ B 0 þ ð V 0 d 3 r 0 3 M ð r 0 Þ ð r r 0 Þ ð r r 0 Þ j j 5 M ð r 0 Þ j j 3 M ð r Þ ¼ w ð r Þ m 0 ð 1 þ w ð r ÞÞ M z ð r Þ w ð r Þ m 0 ð 1 þ w ð r ÞÞ B 0 z ¼) w ð r Þ B z ð r Þ ¼ B 0 z þ ð V 0 d 3 r 0 3 M z ð r 0 Þ ð z z 0 Þ 2 j j 5 M z ð r 0 Þ j j 3 B d z ð r Þ ¼ ð V 0 d 3 r 0 3 w ð r 0 Þ ð z z 0 Þ 2 j j 5 w ð r 0 Þ j j 3 ð V 0 d 3 r 0 w ð r Þ G c ; 3D ð r r 0 Þ 3 ð z 2 r 2 Þ þ k 2 y þ k 2 z q ¼ 4 p ð u 3D ; f Þ Y ‘ m ð u k ; 3D ; f k Þ B d z ð r Þ ¼ B 0 = 1 = w ð r Þ ð Þ þ k 2 y þ k 2 z d 2 k 2 z þ k 2 z þ B z ; 2D ð r Þ ¼ = 1 = w ð r Þ ð Þ G c ; 2D (a) (b) (c) (d) ð Þ = 6. B z ð r Þ ¼ B 0 = 1 = w ð r Þ f g G ð k Þ (a) (b) (c) (d) (a) (b) (c) (d) (a) (b) (c) (d) w ð r Þ ¼ g B d z ð r Þ TE ¼ g B 0 TE = 1 = w ð ð Þ þ k 2 y þ k 2 z w ð r Þ ¼ g B 0 TE = 1 " w 1 g 1 þ w 2 g 2 þ þ w i g i þ þ w n g n Þ þ k 2 y þ k 2 z B z ð r Þ ¼ ð Þ þ w e w ð r Þ ¼ g B d z ð r Þ TE ¼ g B 0 TE = 1 = w ð r Þ ð Þ þ k 2 y þ k 2 z Þ 2 w i g TE w B 0 g i d w i 2 Þ 2 g TE B 0 SNR 2 i w i w 0 g TE w B 0 g i w i w 0 g TE w B 0 g i p s i ; phase SWIM: Susceptibility Mapping as a Means to Visualize Veins and Quant Oxygen Saturation j k j 2 a ð k z Þ ¼ ð k z k z 0 Þ = ð b D k z Þ for j k z k zo j < b g ð k Þ ¼ when j k z k zo j b D k z b ¼ j k za k zo j = ð D k z Þ a ð k z Þ ¼ ð k z k zo Þ = j k za k zo j (a) (b) Effects of Contrast Agents in Susceptibility Weighted T i ð c CA Þ ¼ R i ð c CA Þ ¼ 7 t c 2 1 þ ð v S t c 2 Þ 2 3 t c 1 1 þ ð v I t c 1 Þ 2 2 A 2 S ð S þ 1 Þ t 0 c 2 1 þ ð v S t 0 c 2 Þ 2 6 : 5 t c 2 1 þ ð v S t c 2 Þ 2 1 : 5 t c 1 1 þ ð v I t c 1 Þ 2 þ 2 t c 1 S ð S þ 1 Þ 3 h 2 t 0 c 2 1 þ ð v S t 0 c 2 Þ 2 þ t 0 c 1 D B ð r Þ ¼ cos ð u Þ 2 sin ð u Þ 2 r 2 cos ð 2 f Þ S ð TE Þ ¼ r v l f v ð T 1 ; TR Þ e i w ð TE ; Y ; c CA w f v ð a ; TR ; T 1 Þ ¼ sin ð a Þ f t ð a ; TR ; T 1 Þ ¼ sin ð a Þ W ð r Þ f ð r Þ r ð r Þ e i g D B ð r Þ TE e TE = T * 2 ð ð Y Þ ¼ A * þ B * ð 1 Y Þ þ C * ð 1 Y Þ 2 w ð r Þ w CA ð r Þ D B CA ð r Þ ¼ D w ð r in Þ ¼ 2 g TE B 0 ð cos 2 u 1 = 3 Þ Oxygen Saturation: Quantification A ¼ ½ w ð V ein Þ w ð A rt Þ = ½ k Hct ð 1 Y Þ TE ð 3 cos 2 u 1 u ¼ tan 1 ½ d D x = ½ð n 1 Þ D z ¼ 1 = T * 2 ¼ 1 = T * 2o þ A T 2 ð 1 Y Þ ¼ 13 : 29 ð 1 Y Þ þ Quantification of Oxygen Saturation of Single Cerebral Veins, the Blood Capillary Network, and Its Dependency on Perfusion D x ¼ D x do Hct 1 Y j r j 2 B 0 j r j a ð Þ 6 ð 3 cos 2 u 1 Þ j B 0 j þ ð 1 l Þ S ext e t = T 2ext h ð 28 : 5 Þ h ¼ 1 f ð dv t Þ 1 l þ f ð l dv t Þ f ð x Þ ¼ ð 1 J 0 ð xu Þ S net ð t Þ ¼ ð 1 l Þ S ext e l f ð d v t Þ e d v ¼ g f ð x Þ ¼ p 1 J 0 ðð 3 = 2 Þ xu Þ Integrating Perfusion Weighted Imaging, MR Angiography, and Susceptibility Weighted Imaging Functional Susceptibility Weighted Magnetic Resonance Imaging Complex Thresholding Methods for Eliminating Voxels That Contain Predominantly Noise in Magnetic Resonance Images p ð M ; f Þ ¼ þ A 2 2 AM cos ð f u Þ p M ð M Þ ¼ s ð 2 p = 2 Þ . p M ð M Þ ¼ þ s 2 p ð w Þ ¼ 2 p s = A ð Þ 2 exp ð f u Þ 2 2 s = A ð Þ 2 n 0 ð x ; y Þ ¼ L ð A ; u ; s 2 Þ ¼ 2 p s 2 þ A 2 2 AM i cos ð f i u Þ ð Þ 2 þ y I ð Þ 2 l ¼ L ð ð Þ 2 (a) (b) (c) (d) Automatic Vein Segmentation and Lesion Detection: from SWI-MIPs to MR ¼ j l 2 j j l 3 j ¼ j l 1 j j l 2 l 3 j S ¼ k H k F ¼ ð a b Þ 2 þ ð b c Þ 2 þ ð c a Þ 2 Rapid Acquisition Methods ð Þ d x d y ; ð Þ w ð x ; y ; l D T Þ ¼ i v 0 ð x ; y Þð l D T þ TE ð 0 ÞÞ (a) (b) r x ; y ð Þ ¼ X w ð x ; y Þ ¼ v 0 ð x ; y Þ D T ð Þ ð Þ L D T ð Þ ¼ X ð Þ L l ð Þ D T ð Þ p n . High-Resolution Venographic BOLD MRI of Animal Brain at 9.4 T: Impli v in ¼ 2 p D x 0 ð 1 Y Þ v 0 ð cos 2 u 1 = 3 Þ v out ¼ 2 p D x 0 ð 1 Y Þ v 0 ð a = r Þ 2 ð sin 2 u Þð cos 2 f Þ Susceptibility Weighted Imaging in Rodents f ¼ R pc = ð 1 R pc Þ Ultrashort TE Imaging: Phase and Frequency Mapping of Susceptibility Effects in Short T 2 T M x ð t Þ ¼ M 0 M y ð t Þ ¼ M 0 M z ð t Þ ¼ M 0 ð Þ 1 u ð t Þ ¼ e i v 1 ð t Þ e v 1 ð t Þ e i þ e v 1 ð t Þ e i F ð t Þ ¼ v off t ff F ð t Þ ¼ ff k ð t Þ ¼ S ð k Þ ¼ S ð k Þ ¼ e i ð 2 v off = g G Þ k ; I ð x Þ ¼ I ð x ¼ 0 Þ ¼ ð Þ F ð x ¼ 0 Þ ¼ ff i 1 e i ð v off = g GL Þ k ð t Þ ¼ S ð k Þ ¼ e i 2 v off p ; S ð k Þ ¼ e þ i 2 v off I ð x ¼ 0 Þ ¼ p d k þ ð p d k ¼ 2 p d k I ð x ¼ 0 Þ ¼ F ð x ¼ 0 Þ I ð x ¼ 0 Þ ¼ F ð x ¼ 0 Þ F ð x ¼ 0 Þ v off ð Þ d k x d k y I ð x ¼ y ¼ 0 Þ ¼ S ð k r Þ ¼ e i 2 v off s 0 ð r Þ½ð 1 = T * 2 Þ i 2 ð f f 0 Þ ð 1 = T * 2 Þ 2 þ 4 ð f f 0 Þ 2 Real ½ s 0 ð r Þ ð 1 = T * 2 Þ þ Imag ½ s 0 ð r Þ 2 ð f f 0 Þ ð 1 = T * 2 Þ 2 þ 4 ð f f 0 Þ 2 j S ð r ; f Þj ¼ j s 0 ð r Þj ð 1 = T * 2 Þ 2 þ 4 ð f f 0 Þ 2 dt ¼ M g B ð Þ d M dt ¼ M g B ð 36 : A1 Þ x 0 ¼ i ð Þ x 0 þ C þ exp þ t ð Þ x þ þ C exp t ð Þ x ð 36 : A3 Þ M ð t ¼ 0 Þ ¼ M x ð t Þ ¼ M 0 M y ð t Þ ¼ M 0 APPENDIX Seminal Articles Related to the Development of Susceptibility Weighted Imaging Index