SECTION 1: SKULL AND BRAIN SCALP, SKULL ANATOMICALLY BASED DIFFERENTIALS 4 Skull Normal Variants Miral D. Jhaveri, MD, MBA 6 Scalp Mass, Child Luke L. Linscott, MD, Chang Yueh Ho, MD, and Miral D. Jhaveri, MD, MBA 10 Scalp Mass, Adult Miral D. Jhaveri, MD, MBA 12 Congenital Anomalies of Skull Base Luke L. Linscott, MD, Chang Yueh Ho, MD, and Susan I. Blaser, MD, FRCPC GENERIC IMAGING PATTERNS 18 "Hair on End" Miral D. Jhaveri, MD, MBA 20 Thick Skull, Generalized Miral D. Jhaveri, MD, MBA 24 Thick Skull, Localized Miral D. Jhaveri, MD, MBA 26 Thin Skull, Generalized Miral D. Jhaveri, MD, MBA 28 Thin Skull, Localized Miral D. Jhaveri, MD, MBA 30 Lytic Skull Lesion, Solitary Miral D. Jhaveri, MD, MBA 34 Multiple Lucent Skull Lesions Miral D. Jhaveri, MD, MBA 38 Sclerotic Skull Lesion, Solitary Miral D. Jhaveri, MD, MBA 42 Sclerotic Skull Lesions, Multiple Miral D. Jhaveri, MD, MBA CLINICALLY BASED DIFFERENTIALS 44 Macrocrania/Macrocephaly Luke L. Linscott, MD 50 Microcephaly Luke L. Linscott, MD MENINGES ANATOMICALLY BASED DIFFERENTIALS 56 Dural Calcification(s) Miral D. Jhaveri, MD, MBA 58 Dural-Based Mass, Solitary Miral D. Jhaveri, MD, MBA 62 Dural-Based Masses, Multiple Miral D. Jhaveri, MD, MBA 66 Falx Lesions Miral D. Jhaveri, MD, MBA GENERIC IMAGING PATTERNS 68 Thick Dura/Arachnoid, Generalized Yoshimi Anzai, MD, MPH, Judy Tan, MD, and Miral D. Jhaveri, MD, MBA 70 Pial Enhancement Miral D. Jhaveri, MD, MBA, Yoshimi Anzai, MD, MPH, and Judy Tan, MD 74 Dural Tail Sign Miral D. Jhaveri, MD, MBA VENTRICLES, PERIVENTRICULAR REGIONS ANATOMICALLY BASED DIFFERENTIALS 76 Ventricles, Normal Variants Chang Yueh Ho, MD and Susan I. Blaser, MD, FRCPC 80 Choroid Plexus Lesions, Child Chang Yueh Ho, MD and Karen L. Salzman, MD 82 Choroid Plexus Lesions, Adult Kalen Riley, MD, MBA, Chang Yueh Ho, MD, and Karen L. Salzman, MD 84 Ependymal/Subependymal Lesions Miral D. Jhaveri, MD, MBA, Chang Yueh Ho, MD, and Bronwyn E. Hamilton, MD 90 Lateral Ventricle Mass Karen L. Salzman, MD 94 Thick Septum Pellucidum Karen L. Salzman, MD 96 Foramen of Monro Mass Troy A. Hutchins, MD 100 3rd Ventricle Mass, Anterior Karen L. Salzman, MD 104 3rd Ventricle Mass, Body/Posterior Karen L. Salzman, MD 106 Cerebral Aqueduct/Periaqueductal Lesion Chang Yueh Ho, MD and Karen L. Salzman, MD 112 4th Ventricle Mass, Child Chang Yueh Ho, MD and Karen L. Salzman, MD 116 4th Ventricle Mass, Adult Karen L. Salzman, MD GENERIC IMAGING PATTERNS 118 Bubbly Appearing Intraventricular Mass Chang Yueh Ho, MD and Bronwyn E. Hamilton, MD 122 Ependymal Enhancement Miral D. Jhaveri, MD, MBA and Bronwyn E. Hamilton, MD 126 Ventriculomegaly Luke L. Linscott, MD 132 Small Ventricles Chang Yueh Ho, MD and Bronwyn E. Hamilton, MD 134 Asymmetric Lateral Ventricles Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Bronwyn E. Hamilton, MD 138 Irregular Lateral Ventricles Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Bronwyn E. Hamilton, MD 142 Periventricular Enhancing Lesions Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Bronwyn E. Hamilton, MD MODALITY-SPECIFIC IMAGING FINDINGS 146 Intraventricular Calcification(s) Karen L. Salzman, MD and Miral D. Jhaveri, MD, MBA 150 Periventricular Calcification(s) Luke L. Linscott, MD, Chang Yueh Ho, MD, and Susan I. Blaser, MD, FRCPC 154 Periventricular T2/FLAIR Hyperintense Lesions Troy A. Hutchins, MD, Karen L. Salzman, MD, and Miral D. Jhaveri, MD, MBA EXTRAAXIAL SPACES AND SUBARACHNOID CISTERNS ANATOMICALLY BASED DIFFERENTIALS 158 Subarachnoid Space Normal Variants Karen L. Salzman, MD and Bernadette L. Koch, MD 160 Epidural Mass Sheri L. Harder, MD, FRCPC and Miral D. Jhaveri, MD, MBA 164 Enlarged Sulci, Generalized Chang Yueh Ho, MD and Anne G. Osborn, MD, FACR 168 Effaced Sulci, Generalized Anne G. Osborn, MD, FACR and Chang Yueh Ho, MD 172 Interhemispheric Fissure Cysts Chang Yueh Ho, MD and Anne G. Osborn, MD, FACR 176 CPA Mass, Adult Karen L. Salzman, MD, H. Ric Harnsberger, MD, and Miral D.Jhaveri, MD, MBA 180 Cystic CPA Mass Karen L. Salzman, MD, H. Ric Harnsberger, MD, and Miral D.Jhaveri, MD, MBA 184 Prepontine Cistern Mass Kalen Riley, MD, MBA, Gregory L. Katzman, MD, MBA, and Miral D. Jhaveri, MD, MBA 190 Ventral Foramen Magnum Mass Miral D. Jhaveri, MD, MBA and Karen L. Salzman, MD 194 Dorsal Foramen Magnum Mass Miral D. Jhaveri, MD, MBA and Karen L. Salzman, MD GENERIC IMAGING PATTERNS 198 Solitary Enhancing Cranial Nerve Miral D. Jhaveri, MD, MBA and Anne G. Osborn, MD, FACR 200 Multiple Enhancing Cranial Nerves Miral D. Jhaveri, MD, MBA and Anne G. Osborn, MD, FACR 204 CSF-Like Extraaxial Fluid Collection Miral D. Jhaveri, MD, MBA, Yoshimi Anzai, MD, MPH, and Judy Tan, MD 206 Convexal Subarachnoid Hemorrhage Miral D. Jhaveri, MD, MBA 210 CSF-Like Extraaxial Mass Yoshimi Anzai, MD, MPH, Judy Tan, MD, and Miral D. Jhaveri, MD, MBA 212 Sulcal/Cisternal Enhancement Miral D. Jhaveri, MD, MBA and Sheri L. Harder, MD, FRCPC 216 Fat in Sulci/Cisterns/Ventricles Miral D. Jhaveri, MD, MBA and Yoshimi Anzai, MD, MPH 218 Pneumocephalus Miral D. Jhaveri, MD, MBA MODALITY-SPECIFIC IMAGING FINDINGS 220 Extraaxial Flow Voids Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and James D. Eastwood, MD 222 T1-Hyperintense CSF Miral D. Jhaveri, MD, MBA and Bronwyn E. Hamilton, MD 224 FLAIR Hyperintense Sulci Miral D. Jhaveri, MD, MBA and Bronwyn E. Hamilton, MD 228 T2-Hypointense Extraaxial Lesions Miral D. Jhaveri, MD, MBA and Bronwyn E. Hamilton, MD 232 Hyperdense CSF Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Bronwyn E. Hamilton, MD 234 Hyperdense Extraaxial Mass(es) Miral D. Jhaveri, MD, MBA 236 Hypodense Extraaxial Mass(es) Miral D. Jhaveri, MD, MBA and Bronwyn E. Hamilton, MD BRAIN PARENCHYMA, GENERAL GENERIC IMAGING PATTERNS 240 Multiple Enhancing Lesions, General Karen L. Salzman, MD and Miral D. Jhaveri, MD, MBA 244 Ring-Enhancing Lesion, Solitary Miral D. Jhaveri, MD, MBA, Yoshimi Anzai, MD, MPH, and Judy Tan, MD 250 Ring-Enhancing Lesion, Multiple Yoshimi Anzai, MD, MPH, Judy Tan, MD, and Miral D. Jhaveri, MD, MBA 254 Solitary Cystic Parenchymal Mass, General Anne G. Osborn, MD, FACR and Miral D. Jhaveri, MD, MBA 260 CSF-Like Parenchymal Lesion(s) Anne G. Osborn, MD, FACR, James D. Eastwood, MD, and Miral D. Jhaveri, MD, MBA 266 Cyst With Nodule Troy A. Hutchins, MD, Karen L. Salzman, MD, and Miral D. Jhaveri, MD, MBA 270 Fat and Fat-Like Lesion(s) Miral D. Jhaveri, MD, MBA and Sheri L. Harder, MD, FRCPC MODALITY-SPECIFIC IMAGING FINDINGS 272 Solitary Parenchymal Calcification Miral D. Jhaveri, MD, MBA and Anne G. Osborn, MD, FACR 276 Multiple Parenchymal Calcifications Anne G. Osborn, MD, FACR and Miral D. Jhaveri, MD, MBA 280 Solitary Hyperdense Parenchymal Lesion Miral D. Jhaveri, MD, MBA and Anne G. Osborn, MD, FACR 286 Multiple Hyperdense Parenchymal Lesions Anne G. Osborn, MD, FACR and Miral D. Jhaveri, MD, MBA 292 Solitary Hypodense Parenchymal Lesion Miral D. Jhaveri, MD, MBA and Anne G. Osborn, MD, FACR 296 Multiple Hypodense Parenchymal Lesions Chang Yueh Ho, MD and Karen L. Salzman, MD 300 Multiple Brain Hyperintensities (T2/FLAIR), Common Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Gary M. Nesbit, MD 306 Multiple Brain Hyperintensities (T2/FLAIR), Less Common Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Gary M. Nesbit, MD 312 Multiple Brain Hyperintensities (T2/FLAIR), Rare but Important Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Gary M. Nesbit, MD 318 Multiple Hypointense Foci on T2 Nancy J. Fischbein, MD 320 Multiple Hypointense Foci on GRE/SWI Nancy J. Fischbein, MD 324 T1/T2 Hyperintense Parenchymal Lesions Anne G. Osborn, MD, FACR and Miral D. Jhaveri, MD, MBA 328 T1 Hypointense, T2 Hyperintense Parenchymal Lesions Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Anne G. Osborn, MD, FACR 332 T1/T2 Isointense Parenchymal Lesions Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Anne G. Osborn, MD, FACR 336 Restricted Diffusion, General Miral D. Jhaveri, MD, MBA and Bronwyn E. Hamilton, MD 342 Restricted Diffusion, Cortex Miral D. Jhaveri, MD, MBA 344 Restricted Diffusion, Basal Ganglia Miral D. Jhaveri, MD, MBA 348 T1 Hyperintense Parenchymal Lesion(s) Anne G. Osborn, MD, FACR and Miral D. Jhaveri, MD, MBA CLINICALLY BASED DIFFERENTIALS 352 Brain Tumor in Newborn/Infant Chang Yueh Ho, MD and Susan I. Blaser, MD, FRCPC > 1 Year Chang Yueh Ho, MD and Susan I. Blaser, MD, FRCPC 364 Epilepsy, Child Luke L. Linscott, MD, Chang Yueh Ho, MD, and Bronwyn E. Hamilton, MD 370 Epilepsy, Adult Chang Yueh Ho, MD and Bronwyn E. Hamilton, MD SUPRATENTORIAL BRAIN PARENCHYMA ANATOMICALLY BASED DIFFERENTIALS 372 Asymmetric Cerebral Hemispheres Santhosh Gaddikeri, MD, Gregory L. Katzman, MD, MBA, and Marinos Kontzialis, MD 378 Thick Cerebral Cortex Luke L. Linscott, MD 384 Thin Cortex Chang Yueh Ho, MD and Susan I. Blaser, MD, FRCPC 390 Focal Cortical Mass Chang Yueh Ho, MD and James D. Eastwood, MD 396 Cortical Hyperintensity T2/FLAIR Karen L. Salzman, MD 400 Cortical Enhancement Karen L. Salzman, MD 402 Solitary White Matter Lesion Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Gary M. Nesbit, MD 406 Confluent White Matter Lesions Karen L. Salzman, MD and Gary M. Nesbit, MD 412 Abnormal Shape/Configuration of Corpus Callosum Luke L. Linscott, MD 418 Corpus Callosum Holes Karen L. Salzman, MD 420 Corpus Callosum Lesion Without Mass Effect Karen L. Salzman, MD 422 Corpus Callosum Mass Karen L. Salzman, MD 424 Corpus Callosum Splenium Lesion Troy A. Hutchins, MD 428 Medial Temporal Lobe Lesion Chang Yueh Ho, MD 434 Hippocampal Lesion Chang Yueh Ho, MD 438 Basal Ganglia Calcification Karen L. Salzman, MD 442 Hyperdense Basal Ganglia Karen L. Salzman, MD 444 Hypodense Basal Ganglia Karen L. Salzman, MD 448 T1 Hyperintense Basal Ganglia Karen L. Salzman, MD 452 T2 Hyperintense Basal Ganglia Karen L. Salzman, MD 456 Enlarged Perivascular Spaces Karen L. Salzman, MD 458 Perivascular Space Enhancing Lesions Karen L. Salzman, MD 462 Bilateral Basal Ganglia Lesions Karen L. Salzman, MD 468 Globus Pallidus Lesion(s) Karen L. Salzman, MD 472 Unilateral Thalamic Lesion Karen L. Salzman, MD 474 Bithalamic Lesions Nancy J. Fischbein, MD 478 Pulvinar Sign Karen L. Salzman, MD 480 Tectal (Quadrigeminal Plate) Lesion Karen L. Salzman, MD INFRATENTORIAL BRAIN PARENCHYMA ANATOMICALLY BASED DIFFERENTIALS 482 Large Brainstem Karen L. Salzman, MD 484 Small Brainstem Karen L. Salzman, MD 486 T2 Hyperintense Brainstem, Focal Karen L. Salzman, MD 488 T2 Hyperintense Brainstem, Diffuse Karen L. Salzman, MD 490 Midbrain Lesion Nancy J. Fischbein, MD 494 Pontine Lesion Nancy J. Fischbein, MD 500 Medulla Lesion Nancy J. Fischbein, MD 504 Middle Cerebellar Peduncle Lesion(s) Nancy J. Fischbein, MD 508 Cerebellar Atrophy Chang Yueh Ho, MD and Gregory L. Katzman, MD, MBA 512 Cerebellar Hemisphere Mass Chang Yueh Ho, MD and Gregory L. Katzman, MD, MBA 518 Vermis Mass Chang Yueh Ho, MD and Gregory L. Katzman, MD, MBA 522 Low Cerebellar Tonsils Luke L. Linscott, MD, Chang Yueh Ho, MD, and Gregory L. Katzman, MD, MBA GENERIC IMAGING PATTERNS 524 Cystic-Appearing Posterior Fossa Lesion Luke L. Linscott, MD CLINICALLY BASED DIFFERENTIALS 530 Posterior Fossa Neoplasm, Adult Anne G. Osborn, MD, FACR and Karen L. Salzman, MD 534 Posterior Fossa Neoplasm, Pediatric Chang Yueh Ho, MD and Susan I. Blaser, MD, FRCPC SELLA/JUXTASELLAR, PINEAL REGION ANATOMICALLY BASED DIFFERENTIALS 540 Pineal Region Mass, General Chang Yueh Ho, MD and Gregory L. Katzman, MD, MBA 544 Pineal Gland Mass Chang Yueh Ho, MD and Karen L. Salzman, MD 546 Quadrigeminal Cistern Mass Chang Yueh Ho, MD and Gregory L. Katzman, MD, MBA 548 Pineal + Suprasellar Lesions Karen L. Salzman, MD 550 Sella/Pituitary Normal Variants Kalen Riley, MD, MBA, Anne G. Osborn, MD, FACR, and Karen L. Salzman, MD 552 Sellar/Juxtasellar Calcification Anne G. Osborn, MD, FACR and Karen L. Salzman, MD 556 Enlarged Pituitary Gland Karen L. Salzman, MD and Anne G. Osborn, MD, FACR 558 Intrasellar Lesion Karen L. Salzman, MD and Anne G. Osborn, MD, FACR 560 Cystic Intrasellar Mass Karen L. Salzman, MD and Anne G. Osborn, MD, FACR 562 Suprasellar Mass, Child Chang Yueh Ho, MD and Anne G. Osborn, MD, FACR 568 Suprasellar Mass, Adult Karen L. Salzman, MD 572 Suprasellar Cystic Mass Anne G. Osborn, MD, FACR and Karen L. Salzman, MD 576 Calcified Suprasellar Mass Anne G. Osborn, MD, FACR and Karen L. Salzman, MD 578 Enhancing Suprasellar Mass Kalen Riley, MD, MBA, Anne G. Osborn, MD, FACR, and Karen L. Salzman, MD 580 Sellar/Parasellar Mass With Skull Base Invasion Anne G. Osborn, MD, FACR and Miral D. Jhaveri, MD, MBA 584 Absent/Thin Infundibular Stalk Chang Yueh Ho, MD and Anne G. Osborn, MD, FACR 586 Thick Infundibular Stalk Kalen Riley, MD, MBA, Chang Yueh Ho, MD, and Anne G. Osborn, MD, FACR 588 Hypothalamus Lesion Kalen Riley, MD, MBA, Chang Yueh Ho, MD, and Anne G. Osborn, MD, FACR MODALITY-SPECIFIC IMAGING FINDINGS 592 Hyperdense Suprasellar Mass Kalen Riley, MD, MBA, Anne G. Osborn, MD, FACR, and Karen L. Salzman, MD 594 T1 Hyperintense Suprasellar Mass Karen L. Salzman, MD and Anne G. Osborn, MD, FACR ARTERIES ANATOMICALLY BASED DIFFERENTIALS 596 Multifocal Arterial Narrowing Hediyeh Baradaran, MD and J. Scott McNally, MD, PhD 600 Vessel Wall Abnormalities Hediyeh Baradaran, MD and J. Scott McNally, MD, PhD 604 Fusiform Arterial Enlargement Hediyeh Baradaran, MD, Chang Yueh Ho, MD, and Sheri L. Harder, MD, FRCPC MODALITY-SPECIFIC IMAGING FINDINGS 606 Hyperattenuating ("Dense") Artery Hediyeh Baradaran, MD, Sheri L. Harder, MD, FRCPC, and Karen L. Salzman, MD VEINS, VENOUS SINUSES ANATOMICALLY BASED DIFFERENTIALS 608 Dural Sinus Lesion, General Karen L. Salzman, MD, Bronwyn E. Hamilton, MD, and Anne G. Osborn, MD, FACR 612 Enlarged Cortical Veins Karen L. Salzman, MD and James D. Eastwood, MD 614 Prominent/Enlarged Deep (Medullary/Ependymal) Veins Karen L. Salzman, MD and James D. Eastwood, MD 618 Abnormally Enhancing Medullary Veins Hediyeh Baradaran, MD 622 Unilateral Cavernous Sinus Mass Santhosh Gaddikeri, MD, Marinos Kontzialis, MD, and Anne G. Osborn, MD, FACR 626 Bilateral Cavernous Sinus Lesions Karen L. Salzman, MD and Anne G. Osborn, MD, FACR 630 Meckel Cave Lesion Kalen Riley, MD, MBA, Anne G. Osborn, MD, FACR, and Karen L. Salzman, MD MODALITY-SPECIFIC IMAGING FINDINGS 634 Hyperdense Dural Sinus Kalen Riley, MD, MBA, Anne G. Osborn, MD, FACR, and Karen L. Salzman, MD 638 GRE/SWI Venous Abnormalities Kalen Riley, MD, MBA and Miriam E. Peckham, MD CRANIAL NERVES CLINICALLY BASED DIFFERENTIALS 640 Hemifacial Spasm Nicholas A. Koontz, MD 644 Sensorineural Hearing Loss in Adult Nicholas A. Koontz, MD 648 Sensorineural Hearing Loss in Child Bernadette L. Koch, MD 654 Bitemporal Heteronymous Hemianopsia Kristine M. Mosier, DMD, PhD 660 Homonymous Hemianopsia Kristine M. Mosier, DMD, PhD 664 Oculomotor, Trochlear, or Abducens Neuropathy Nicholas A. Koontz, MD 670 Trigeminal Neuralgia Nicholas A. Koontz, MD 674 Complex Cranial Nerve IX-XII Neuropathy Nicholas A. Koontz, MD 680 Horner Syndrome Nicholas A. Koontz, MD SECTION 2: SPINE TRANSSPATIAL ANATOMICALLY BASED DIFFERENTIALS 688 Cervical, Chronic Posttraumatic Abnormality Jeffrey S. Ross, MD 690 Cervical, Lower, Posttraumatic Bony Abnormality Jeffrey S. Ross, MD and Julia R. Crim, MD 692 Thoracic Bony Trauma Jeffrey S. Ross, MD and Julia R. Crim, MD 694 Lumbar Bony Trauma Jeffrey S. Ross, MD and Julia R. Crim, MD GENERIC IMAGING PATTERNS 696 Kyphosis Jeffrey S. Ross, MD, Julia R. Crim, MD, and Kevin R. Moore, MD 698 Kyphoscoliosis, Child Jeffrey S. Ross, MD, Julia R. Crim, MD, and Kevin R. Moore, MD 700 Platyspondyly, Diffuse Jeffrey S. Ross, MD, Julia R. Crim, MD, and Kevin R. Moore, MD 702 Sacral Mass, Adult Jeffrey S. Ross, MD 706 Sacrococcygeal Mass, Pediatric Jeffrey S. Ross, MD and Kevin R. Moore, MD 710 Sacral Deformity Jeffrey S. Ross, MD, Bryson Borg, MD, and Kevin R. Moore, MD 714 Multicompartmental Mass Jeffrey S. Ross, MD CLINICALLY BASED DIFFERENTIALS 720 Acute Back Pain/Radiculopathy, Postoperative Jeffrey S. Ross, MD and Kevin R. Moore, MD 726 Chronic Back Pain/Radiculopathy, Postoperative Jeffrey S. Ross, MD and Kevin R. Moore, MD 732 Acute Upper Extremity Pain/Weakness Jeffrey S. Ross, MD and Kevin R. Moore, MD 738 Lower Extremity Pain Jeffrey S. Ross, MD and Bryson Borg, MD 742 Back Pain, Adult Jeffrey S. Ross, MD and Bryson Borg, MD 748 Back Pain, Pediatric Jeffrey S. Ross, MD and Kevin R. Moore, MD CRANIOVERTEBRAL JUNCTION ANATOMICALLY BASED DIFFERENTIALS 752 Craniocervical Junction Acute Injury Jeffrey S. Ross, MD and Julia R. Crim, MD 756 Craniovertebral Junction Abnormality, General Jeffrey S. Ross, MD and Julia R. Crim, MD 760 Craniovertebral Junction Soft Tissue Abnormality Jeffrey S. Ross, MD GENERIC IMAGING PATTERNS 764 C1-C2 Instability Jeffrey S. Ross, MD 768 Odontoid Deformity Jeffrey S. Ross, MD and Julia R. Crim, MD VERTEBRAL BODY, POSTERIOR ELEMENTS ANATOMICALLY BASED DIFFERENTIALS 770 Congenital Vertebral Anomalies Jeffrey S. Ross, MD and Julia R. Crim, MD 772 Cervical Bony Fusion Jeffrey S. Ross, MD, Julia R. Crim, MD, and Kevin R. Moore, MD GENERIC IMAGING PATTERNS 774 Flattened Vertebral Body, Solitary Jeffrey S. Ross, MD and Julia R. Crim, MD 776 Flattened Vertebral Body, Multiple Jeffrey S. Ross, MD, Julia R. Crim, MD, and Kevin R. Moore, MD 778 Dysmorphic Vertebral Body Jeffrey S. Ross, MD, Kevin R. Moore, MD, and Julia R. Crim, MD 780 Enlarged Vertebral Body/Posterior Element Jeffrey S. Ross, MD 784 Enlarged Neural Foramen Jeffrey S. Ross, MD and Kevin R. Moore, MD 786 Vertebral Body Scalloping/Widened Canal Jeffrey S. Ross, MD and Bryson Borg, MD 788 Spondylolisthesis Jeffrey S. Ross, MD and Kevin R. Moore, MD 792 Bony Lesion, Aggressive Jeffrey S. Ross, MD and Lubdha M. Shah, MD 796 Fracture, Vertebral Body Jeffrey S. Ross, MD, Julia R. Crim, MD, and Kevin R. Moore, MD 800 Facet Abnormality, Nontraumatic Jeffrey S. Ross, MD and Lubdha M. Shah, MD 802 Fracture, Posterior Element Jeffrey S. Ross, MD, Julia R. Crim, MD, and Kevin R. Moore, MD 804 Pedicle Abnormality Jeffrey S. Ross, MD MODALITY-SPECIFIC IMAGING FINDINGS 808 Enlarged Vertebral Body, Soap Bubble Expansion Jeffrey S. Ross, MD and Lubdha M. Shah, MD 812 Vertebral Body Sclerosis, Focal Jeffrey S. Ross, MD 816 Vertebral Body Sclerosis, Diffuse Jeffrey S. Ross, MD and Bryson Borg, MD 818 Vertebral Body Thickened Bony Trabeculae Jeffrey S. Ross, MD and Lubdha M. Shah, MD 820 Vertebral Body, T1 Hyperintense Signal, Diffuse Jeffrey S. Ross, MD and Kevin R. Moore, MD 822 Vertebral Body, T1 Hyperintense Signal, Focal Jeffrey S. Ross, MD and Kevin R. Moore, MD 824 Vertebral Body, T1 Hypointense Signal, Diffuse Jeffrey S. Ross, MD and Kevin R. Moore, MD 828 Vertebral Body, T1 Hypointense Signal, Focal Jeffrey S. Ross, MD and Bryson Borg, MD INTERVERTEBRAL DISC, ENDPLATE GENERIC IMAGING PATTERNS 830 Disc Contour Abnormality Jeffrey S. Ross, MD 834 Intervertebral Disc/Endplate Irregularity Jeffrey S. Ross, MD 838 Vertebral Endplate Contour Abnormality Jeffrey S. Ross, MD and Julia R. Crim, MD MODALITY-SPECIFIC IMAGING FINDINGS 842 Intervertebral Disc, T1 Hypointense Jeffrey S. Ross, MD 844 Intervertebral Disc, T2 Hyperintense Jeffrey S. Ross, MD 846 Vertebral Endplate Signal Abnormality Jeffrey S. Ross, MD EXTRADURAL ANATOMICALLY BASED DIFFERENTIALS 848 Epidural Mass Jeffrey S. Ross, MD and Bryson Borg, MD 854 Ventral/Lateral Paraspinal Mass Jeffrey S. Ross, MD GENERIC IMAGING PATTERNS 856 Paraspinal Muscle Abnormality Jeffrey S. Ross, MD 858 Extradural Lesions, Multiple Jeffrey S. Ross, MD and Bryson Borg, MD 860 Extradural Lesion, No Enhancement Jeffrey S. Ross, MD 862 Extradural Lesion, Solid Enhancement Jeffrey S. Ross, MD and Kevin R. Moore, MD 866 Epidural Fluid Jeffrey S. Ross, MD MODALITY-SPECIFIC IMAGING FINDINGS 870 Soft Tissue Calcification, Paraspinal Jeffrey S. Ross, MD 872 Extradural, Normal Marrow Signal Jeffrey S. Ross, MD and Kevin R. Moore, MD 876 Extradural, Abnormal Marrow Signal Jeffrey S. Ross, MD and Kevin R. Moore, MD 880 Extradural Lesion, T1 Hyperintense Jeffrey S. Ross, MD, Bryson Borg, MD, and Kevin R. Moore, MD 882 Extradural Lesion, T1 Hypointense Jeffrey S. Ross, MD, Bryson Borg, MD, and Kevin R. Moore, MD 886 Extradural Lesion, T2 Hyperintense, T1 Isointense Jeffrey S. Ross, MD 890 Extradural Lesion, T2 Hypointense, T1 Hypointense Jeffrey S. Ross, MD, Bryson Borg, MD, and Kevin R. Moore, MD CLINICALLY BASED DIFFERENTIALS 892 Lumbar Soft Tissue Mass, Pediatric Jeffrey S. Ross, MD and Kevin R. Moore, MD INTRADURAL EXTRAMEDULLARY ANATOMICALLY BASED DIFFERENTIALS 896 Cauda Equina Enhancement, Diffuse Jeffrey S. Ross, MD 900 Subarachnoid Space Narrowing Jeffrey S. Ross, MD and Bryson Borg, MD 902 Intradural Extramedullary, Leptomeningeal Enhancement Jeffrey S. Ross, MD and Kevin R. Moore, MD GENERIC IMAGING PATTERNS 906 Intradural Extramedullary Lesion, No Enhancement Jeffrey S. Ross, MD and Kevin R. Moore, MD 910 Intradural Extramedullary Lesion, Solid Enhancement Jeffrey S. Ross, MD and Kevin R. Moore, MD 914 Intradural Lesion, Serpentine Jeffrey S. Ross, MD 916 Intradural Extramedullary Lesion, Multiple Jeffrey S. Ross, MD and Bryson Borg, MD MODALITY-SPECIFIC IMAGING FINDINGS 920 Intradural Extramedullary Lesion, Ring/Peripheral Enhancement Jeffrey S. Ross, MD 924 Intradural Extramedullary Lesion, T1 Hyperintense Jeffrey S. Ross, MD and Kevin R. Moore, MD 926 Intradural Extramedullary Lesion, T1 Hypointense Jeffrey S. Ross, MD and Kevin R. Moore, MD 930 Intradural Extramedullary Lesion, T1 Hypointense, T2 Hypointense Jeffrey S. Ross, MD and Kevin R. Moore, MD 932 Intradural Extramedullary Lesion, T2 Hyperintense, T1 Isointense Jeffrey S. Ross, MD and Kevin R. Moore, MD CLINICALLY BASED DIFFERENTIALS 934 Cauda Equina Syndrome Jeffrey S. Ross, MD and Bryson Borg, MD INTRAMEDULLARY ANATOMICALLY BASED DIFFERENTIALS 936 Intramedullary Mass Jeffrey S. Ross, MD and Bryson Borg, MD 940 Conus Abnormality Jeffrey S. Ross, MD and Bryson Borg, MD GENERIC IMAGING PATTERNS 944 Intramedullary Lesions, Multiple Jeffrey S. Ross, MD, Lubdha M. Shah, MD, and Kevin R.Moore, MD 946 Intramedullary Lesion, Solid Enhancement Jeffrey S. Ross, MD, Lubdha M. Shah, MD, and Kevin R. Moore, MD 950 Intramedullary Lesion, No Enhancement Jeffrey S. Ross, MD, Lubdha M. Shah, MD, and Kevin R. Moore, MD 952 Intramedullary Lesion, Diffuse/Ill-Defined Enhancement Jeffrey S. Ross, MD and Kevin R. Moore, MD 956 Intramedullary Lesion, Ring/Peripheral Enhancement Jeffrey S. Ross, MD, Lubdha M. Shah, MD, and Kevin R. Moore, MD MODALITY-SPECIFIC IMAGING FINDINGS 958 Intramedullary Lesion, T1 Hypointense, T2 Hypointense Jeffrey S. Ross, MD, Lubdha M. Shah, MD, and Kevin R. Moore, MD 960 Intramedullary Lesion, T1 Hypointense Jeffrey S. Ross, MD and Lubdha M. Shah, MD 962 Intramedullary Lesion, T2 Hyperintense, T1 Isointense Jeffrey S. Ross, MD and Lubdha M. Shah, MD 966 Intramedullary Lesion, T1 Hyperintense Jeffrey S. Ross, MD and Lubdha M. Shah, MD 972 Cord Lesion, T2 Hyperintense, Ventral Jeffrey S. Ross, MD and Lubdha M. Shah, MD 974 Cord Lesion, T2 Hyperintense, Dorsal Jeffrey S. Ross, MD 978 Cord Lesion, T2 Hyperintense, Central Jeffrey S. Ross, MD and Lubdha M. Shah, MD CLINICALLY BASED DIFFERENTIALS 984 Myelopathy Jeffrey S. Ross, MD and Kevin R. Moore