廉状细胞贫血骨改变的影像学诊断

Oni Blackstock, HMS III Gillian Lieberman, MD Radiologic Manifestations of Bone Disease in Sickle Cell Anemia Oni J. Blackstock, HMS III Gillian Lieberman, MD March 2003 2 Oni Blackstock, HMS III Gillian Lieberman, MD Presentation Outline • Meet patient #1 • MSK imaging modalities • Brief review of Sickle cell anemia and its clinical manifestations • Radiologic imaging of the bone complications of SCA 3 Oni Blackstock, HMS III Gillian Lieberman, MD Meet Patient #1 • 44-year old African-American male with hx of SCA and associated chronic pain syndrome • Presents with complaint of left knee pain • Reports increased pain while walking and occasionally at rest • Has had to “dip” into MSContin for additional analgesia 4 Oni Blackstock, HMS III Gillian Lieberman, MD Bone Imaging modalities • Plain radiograph: – initial radiologic evaluation of the majority of suspected musculoskeletal abnormalities – Relatively specific in differentiating potential etiologies of lesion b/c of proven ability to characterize features of the lesion – May not detect certain processes until they are far progressed 5 Oni Blackstock, HMS III Gillian Lieberman, MD Bone imaging modalities • CT – Can detect lesions not seen on routine radiographs or when plain film evaluation is difficult due to nature of lesion or anatomic site – best technique in assessment of matrix mineralization, cortical detail, and detection of the cystic and fatty lesions – Can identify subtle bony abnormalities (occult fractures) and their relationship to adjacent organs – May fail to demonstrate early vascular and marrow abnormalities 6 Oni Blackstock, HMS III Gillian Lieberman, MD Bone imaging modalities • MRI – Method of choice for imaging the soft tissues of MSK system – Sensitive to changes in bone marrow (i.e. subtle marrow edema, marrow infarcts) – Can detect and stage primary bone tumors and occult bony metastases – Difficulty visualizing fine bone detail or small calcifications 7 Oni Blackstock, HMS III Gillian Lieberman, MD Bone imaging modalities • Bone radionuclide scan – Sensitive, but nonspecific for measuring bone formation and perfusion – Detects lesions not otherwise seen on radiograph – Effective for imaging bone marrow and identifying areas of red marrow replacement – Effective screen for detecting multiple lesions – Lacks sufficient spatial resolution to detail extent and anatomic involvement of disease 8 Oni Blackstock, HMS III Gillian Lieberman, MD Bone imaging modalities • Ultrasound – High frequency transducers allow markedly improved image resolution – Can detect joint effusions, subperiosteal fluid, soft tissue masses, congenital hip dysplasias, etc. – Ineffective in visualizing bone detail 9 Oni Blackstock, HMS III Gillian Lieberman, MD Pt #1: AP films of left knee BIDMC PACS Ill-defined sclerotic densities 10 Oni Blackstock, HMS III Gillian Lieberman, MD Pt #1: Lateral oblique of knee BIDMC PACS Ill-defined sclerotic densities 11 Oni Blackstock, HMS III Gillian Lieberman, MD Differential dx for multiple sclerotic densities • Bone infarct • Chronic osteomyelitis • Osteoblastic metastases • Enchondromatosis • Bone islands 12 Oni Blackstock, HMS III Gillian Lieberman, MD Pt #1: Left knee MR – T2 sagittal heterogeneous bone marrow BIDMC PACS 13 Oni Blackstock, HMS III Gillian Lieberman, MD Pt #1: Left tibia MR – T2 axial diffusely heterogeneous bone marrow BIDMC PACS sclerotic bone 14 Oni Blackstock, HMS III Gillian Lieberman, MD Pt #1: Left knee MR - coronal BIDMC PACS heterogeneous bone marrow sclerotic bone 15 Oni Blackstock, HMS III Gillian Lieberman, MD Differential dx of bone infarct* • Idiopathic • Occlusive vascular disease • Sickle cell anemia • Fat embolism • Infection, osteomyelitis *diff dx for diametaphyseal ischemia 16 Oni Blackstock, HMS III Gillian Lieberman, MD Quick Review of SCA • Most common hemoglobin variant in the world (HbS) • Autosomal recessive • ~8% of African Americans are carriers • High frequency of HbS gene attributed to “balanced polymorphism” • Clinical severity can vary among those afflicted with SCA http://peptide.ncsa.uiuc.edu/tutorials_current/Sickle_Cell_Anemia/SC2001/intro.html 17 Oni Blackstock, HMS III Gillian Lieberman, MD Pathogenesis of SCA • Mutation endows deoxy HbS new ability to polymerize distorting the RBC contours = HbS Nucleation Growth Alignment 18 Oni Blackstock, HMS III Gillian Lieberman, MD Pathophysiology of SCA • In addition to polymerization, – Alteration in RBC membrane and cytoskeleton – Increased RBC adherence to vascular endothelium – Disordered RBC volume control – The above factors act in concert to contribute to the vasooclusive episodes and hemolysis seen in SCA http://carnegieinstitution.org/first_light_case/horn/lessons/sickle.html 19 Oni Blackstock, HMS III Gillian Lieberman, MD Clinical manifestations of SCA • Symptoms typically begin after 6 mo. of age • Heterogeneity in clinical and hematolgic severity • Hematologic: – chronic anemia – acute severe anemia (splenic sequestration, aplastic crisis, hyperhemolytic crisis) – acute vassoclusive episodes • Gastrointestinal: pigmented gallstones • Neurologic: – Transient ischemic attacks – infarctive stroke – intracerebral hemorrhage – retinopathy 20 Oni Blackstock, HMS III Gillian Lieberman, MD Clinical Manifestations of SCA • Cardiac: acute myocardial infarction and high output failure • Pulmonary: acute chest syndrome (incl. pneumonia and infarction due to in situ thrombosis) • Renal: – papillary necrosis – focal glomerulosclerosis • Infectious: bacteremia, osteomyelitis, meningitis 21 Oni Blackstock, HMS III Gillian Lieberman, MD Bone complications in SCA • Among the most common manifestations of SCA • Due to one or both of the following factors: – Bone marrow hyperplasia secondary to chronic hemolysis – Vaso-occlusion leading to ischemia and infarction www.ex.ac.uk/shipss/medhist/ 22 Oni Blackstock, HMS III Gillian Lieberman, MD Marrow hyperplasia BIDMC PACS • widespread expansion of hematopoeitic bone marrow throughout the body • Commonly seen in chronic hemolytic anemias fatty marrow hematopoeitic red marrow 23 Oni Blackstock, HMS III Gillian Lieberman, MD Skull – marrow hyperplasia Lonergan GJ, et. al. Sickle Cell Anemia. AFIP Archives 2001; 21:971-994 Reynolds, J.The Skull and spine. Seminars in Roentgenology July 1987; 22:168-175 widened diploic space red bone marrow 24 Oni Blackstock, HMS III Gillian Lieberman, MD Skull – marrow hyperplasia Lonergan GJ, et. al. Sickle Cell Anemia. AFIP Archives 2001; 21:971-994 Hair-on-end appearance • Occurs secondary to thinning of the outer table • Not frequently seen in SCA, but more common in β-thalassemia 25 Oni Blackstock, HMS III Gillian Lieberman, MD Spinal complications of SCA • Vertebral sclerosis due to many small infarcts beginning early in life • Central cupping of the end-plate (aka H- shaped vertebrae) • Vertebral collapse 26 Oni Blackstock, HMS III Gillian Lieberman, MD H-shaped vertebrae BIDMC PACS ACR 27 Oni Blackstock, HMS III Gillian Lieberman, MD Vertebral blood supply Reynolds, J.The Skull and spine. Seminars in Roentgenology July 1987; 22:168-175 28 Oni Blackstock, HMS III Gillian Lieberman, MD Hands and Feet Gaston, M. Sickle cell disease: An overview. Seminars in Roentgenology July 1987; 22:150-159 • Dactylitis also known as hand- foot syndrome • Most often occurs between 6 and 18 months of age • Usually the first ischemic manifestation of SCA • May involve one bone or multiple bones 29 Oni Blackstock, HMS III Gillian Lieberman, MD Dactylitis soft tissue swelling of index finger periostitis along 3rd through 5th metacarpals Diff dx includes: •Pyogenic osteomyelitis (esp. Salmonella) •Tuberculosis Lonergan GJ, et. al. Sickle Cell Anemia. AFIP Archives 2001; 21:971-994 30 Oni Blackstock, HMS III Gillian Lieberman, MD Generalized Osteosclerosis • secondary to multiple widespread tiny infarcts • differential dx includes osteoblastic mets BIDMC PACS 31 Oni Blackstock, HMS III Gillian Lieberman, MD Long bone circulation • The nutrient artery supplies the medullary cavity and inner cortex • Multiple periosteal vessels supply the outer cortex • The metaphyseal and epiphyseal regions are well-perfused by their own network of vessels Bohrer SP. Bone ischemia and infarction in sickle cell disease. St. Louis: Warren H. Green Inc., 1981 32 Oni Blackstock, HMS III Gillian Lieberman, MD Shoulder: bone infarct BIDMC PACS metadiaphyseal medullary infarct 33 Oni Blackstock, HMS III Gillian Lieberman, MD Lower extremity infarcts-bone scan Increased uptake • Targets bone with Tc-99m methylene diphosphonate • Immediately after infarction, scan demonstrates decreased uptake •With reactive bone formation, there is increased uptake •May be difficult to distinguish infarct from osteomyelitis BrighamRADS website 34 Oni Blackstock, HMS III Gillian Lieberman, MD Pt #1 revisited: Plain film of hips - AP BIDMC PACS sclerosis of femoral head sclerosis of femoral head 35 Oni Blackstock, HMS III Gillian Lieberman, MD Companion pt: coronal Hip MR flattened femoral head BIDMC PACS low signal intensity in femoral head 36 Oni Blackstock, HMS III Gillian Lieberman, MD Femoral head anatomy • vascular supply to femoral head is an end-organ system with poor development of collaterals • femoral head more vulnerable to episodes of vaso-occlusion http://home.pacific.net.au/~rossjones/avn.htm 37 Oni Blackstock, HMS III Gillian Lieberman, MD Complications of bone infarction • Fractures – Resulting from full thickness cortical necrosis • Osteomyelitis – Necrotic bone marrow fertile site for 2º infection – Most common offender is Salmonella • Growth disturbances – Usually secondary to deficiency in the nutrient artery circulation to the central region of the metaphyseal side of the growth plate 38 Oni Blackstock, HMS III Gillian Lieberman, MD Radiographic progression of osteomyelitis Initial radiograph 7 days later 5 weeks later periostitis central lucency Lonergan GJ, et. al. Sickle Cell Anemia. AFIP Archives 2001; 21:971-994 39 Oni Blackstock, HMS III Gillian Lieberman, MD Summary • Bone abnormalities in SCA result secondary to marrow hyperplasia and episodes of ischemia leading to infarction • Multiple modalities can be used in conjunction with one another to image these bony changes • Notably, MRI is most sensitive to the detection of bone marrow changes which are commonly seen in SCA 40 Oni Blackstock, HMS III Gillian Lieberman, MD References • Reynolds, J.The Skull and spine. Seminars in Roenthenology July 1987; 22:168-175 • Lonergan GJ, et. al. Sickle Cell Anemia. AFIP Archives 2001; 21:971-994 • Gaston, M. Sickle cell disease: An overview. Seminars in Roentgenology July 1987; 22:150-159 • Bohrer SP. Bone ischemia and infarction in sickle cell disease. St. Louis: Warren H. Green Inc., 1981 • Alvavi A, et al. Scinitgraphic Examination of Bone and Marrow Infarcts in Sickle cell Disorders. Seminars in Roentgenology. July 1987;22:213-223 • Bohrer, S. Bone changes in the Extremities in Sickle Cell Anemia. Seminars in Roentgenology.July 1987;22:176-185 41 Oni Blackstock, HMS III Gillian Lieberman, MD Acknowledgments • Gillian Lieberman, MD • Pamela Lepkowski • Ferris Hall, MD • Kemi Babagbemi, MD • Daniel Saurborn, MD • Joe Makris, MD • The patients!! • Larry Barbaras • Cara Lyn D’amour Radiologic Manifestations of Bone Disease in Sickle Cell Anemia Presentation Outline Meet Patient #1 Bone Imaging modalities Bone imaging modalities Bone imaging modalities Bone imaging modalities Bone imaging modalities Pt #1: AP films of left knee Pt #1: Lateral oblique of knee Differential dx for multiple sclerotic densities Pt #1: Left knee MR – T2 sagittal Pt #1: Left tibia MR – T2 axial Pt #1: Left knee MR - coronal Differential dx of bone infarct* Quick Review of SCA Pathogenesis of SCA Pathophysiology of SCA Clinical manifestations of SCA Clinical Manifestations of SCA Bone complications in SCA Marrow hyperplasia Skull – marrow hyperplasia Skull – marrow hyperplasia Spinal complications of SCA H-shaped vertebrae Vertebral blood supply Hands and Feet Dactylitis Generalized Osteosclerosis Long bone circulation Shoulder: bone infarct Lower extremity infarcts-bone scan Pt #1 revisited: Plain film of hips - AP Companion pt: coronal Hip MR Femoral head anatomy Complications of bone infarction Radiographic progression of osteomyelitis Summary Slide Number 40 Acknowledgments