Bluemke D A, Zerhouni E A
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA.
Top Magn Reson Imaging. 1996 Aug;8(4):231-46. doi: 10.1097/00002142-199608000-00003.
Avascular necrosis (AVN) is characterized by death of both trabecular bone as well as bone marrow elements. Weight-bearing bone becomes mechanically weakened and may eventually collapse, secondarily leading to osteoarthritis and debilitating pain. Early diagnosis and treatment of this entity are crucial because it affects relatively young individuals, and treatment options for advanced disease are limited. Magnetic resonance imaging (MRI) has emerged as the modality of choice for the evaluation of avascular necrosis of bone. We will discuss applications of MRI for early diagnosis, for monitoring therapy, and for its potential role in assessing individuals at risk of AVN. Although bone scintigraphy using single photon emission computed tomography (CT) may be nearly as accurate as MRI, MRI offers a more specific diagnosis in the patient who presents with hip pain of uncertain etiology. In addition, lesion size and location can be more easily assessed on magnetic resonance images, and this has been shown to relate to prognosis and need for treatment. We will review the pathophysiologic mechanisms of AVN and the current use of MRI in the diagnosis of this condition.
缺血性坏死（AVN）的特征是小梁骨以及骨髓成分的死亡。负重骨的机械强度减弱，最终可能塌陷，继而导致骨关节炎和使人衰弱的疼痛。对该疾病进行早期诊断和治疗至关重要，因为它影响的是相对年轻的个体，而针对晚期疾病的治疗选择有限。磁共振成像（MRI）已成为评估骨缺血性坏死的首选方式。我们将讨论MRI在早期诊断、监测治疗以及评估有AVN风险个体中的潜在作用。尽管使用单光子发射计算机断层扫描（CT）的骨闪烁显像可能与MRI几乎一样准确，但对于病因不明的髋部疼痛患者，MRI能提供更具特异性的诊断。此外，在磁共振图像上可以更轻松地评估病变大小和位置，并且这已被证明与预后和治疗需求相关。我们将回顾AVN的病理生理机制以及目前MRI在该疾病诊断中的应用。
