ABSTRACT

Luis Luna Alcalá, Antonio Luna, and Christine Menias

CONTENTS

19.1 Introduction ................................................................................................................................................................. 410 19.2 Anatomy ....................................................................................................................................................................... 411 19.3 MRI Technique ............................................................................................................................................................ 412 19.4 Normal MRI Appearance .......................................................................................................................................... 414 19.5 Normal Variants .......................................................................................................................................................... 414 19.6 Polysplenia Syndrome ................................................................................................................................................ 415 19.7 Splenomegaly ............................................................................................................................................................... 415 19.8 Hemochromatosis (Hemosiderosis and Sickle Cell Disease) ............................................................................... 416 19.9 Trauma .......................................................................................................................................................................... 416 19.10 Infectious Lesions (Infection) .................................................................................................................................... 417 19.11 Cysts .............................................................................................................................................................................. 418 19.12 Vascular Lesions.......................................................................................................................................................... 419

19.12.1 Focal Vascular Lesions ................................................................................................................................. 419 19.12.1.1 Benign Tumors ............................................................................................................................. 419 19.12.1.2 Malignant Neoplasms ................................................................................................................. 424 19.12.1.3 Non-Neoplastic Lesions .............................................................................................................. 426

19.12.2 Diffuse ............................................................................................................................................................ 427 19.12.2.1 Arteriovenous Malformation ..................................................................................................... 427 19.12.2.2 Hemangiomatosis ........................................................................................................................ 427 19.12.2.3 Lymphangioma ............................................................................................................................ 428 19.12.2.4 Peliosis ........................................................................................................................................... 429

19.12.3 Other Vascular Diseases .............................................................................................................................. 429 19.12.3.1 Splenic Artery Aneurysms ......................................................................................................... 429 19.12.3.2 Splenic Vein Thrombosis ............................................................................................................ 430

19.13 Nonvascular Tumors .................................................................................................................................................. 430 19.13.1 Benign Tumors .............................................................................................................................................. 430

19.13.1.1 Hamartomas ................................................................................................................................. 430 19.13.1.2 Fatty Tumors: Lipoma and Angiomyolipoma ......................................................................... 431

19.13.2 Malignant Nonvascular Tumors ................................................................................................................ 431 19.13.2.1 Lymphoma .................................................................................................................................... 431 19.13.2.2 Leukemia ...................................................................................................................................... 432 19.13.2.3 Metastases ..................................................................................................................................... 433 19.13.2.4 Other Primary Sarcomas of the Spleen .................................................................................... 433 19.13.2.5 Splenic Cystoadenocarcinoma ................................................................................................... 435

19.14 Miscellaneous .............................................................................................................................................................. 435 19.14.1 Storage Diseases: Gaucher and Niemann-Pick Diseases ....................................................................... 435 19.14.2 Amyloidosis ................................................................................................................................................... 435 19.14.3 Sarcoidosis ..................................................................................................................................................... 437 19.14.4 Gamna-Gandy Bodies ................................................................................................................................. 438 19.14.5 Inammatory Pseudotumor ....................................................................................................................... 438 19.14.6 Extramedullary Hematopoiesis.................................................................................................................. 438

19.15 Conclusions .................................................................................................................................................................. 439 References ................................................................................................................................................................................ 440

The spleen is probably the least studied abdominal organ in the radiological literature. Although it is an uncommon site for primary disease, the involvement of the spleen in trauma, vascular, inammatory, hematologic, oncologic, or storage disorders is not rare. However, the frequency of splenic abnormalities is low, with the majority presenting as incidental ndings without clinical signicance. With this perspective, both the search and characterization of diseases involving the spleen are challenging for radiologists.