Ketema Amanuel A, Gebregiorigis Bemnet T, Abera Michael T, Amha Lidet G, Semayneh Sonia W
Department of Radiology, School of Medicine, Addis Ababa University, Addis Ababa, Ethiopia.
Department of Radiology, Pioneer Diagnostic Center, Addis Ababa, Ethiopia.
Radiol Case Rep. 2024 Jul 26;19(10):4289-4292. doi: 10.1016/j.radcr.2024.06.061. eCollection 2024 Oct.
Osteonecrosis is the death of bone cells due to insufficient blood supply; radiotherapy for various underlying malignancies is one of the uncommon causes. Microvascular damage or underlying tissue fibrosis, which leads to an ischemic environment and cell death, is a proposed mechanism. Factors influencing risk of radiation induced AVN include type of radiation whether external beam radiotherapy or brachytherapy, age of the patient, included body part and concomitant additional steroid or chemotherapy treatment. In this case report we brought a case of 40-year-old male patient with right proximal thigh leiomyosarcoma who underwent surgical resection and adjuvant radiotherapy, about a year later when Pelvic MR was done for evaluation of surgical bed and tumor progress right femoral head AVN was detected, the patient was asymptomatic. The exact cut-off radiation dose that causes AVN is unknown and varies across studies, necessitating a cautious study of joints included in the radiation field even in asymptomatic patients for early diagnosis and to prevent morbidity associated with delayed diagnosis.
骨坏死是由于血液供应不足导致的骨细胞死亡；针对各种潜在恶性肿瘤的放射治疗是其罕见病因之一。微血管损伤或潜在的组织纤维化会导致缺血环境和细胞死亡，这是一种提出的机制。影响放射性股骨头缺血性坏死（AVN）风险的因素包括放疗类型（无论是外照射放疗还是近距离放疗）、患者年龄、受累身体部位以及同时进行的额外类固醇或化疗治疗。在本病例报告中，我们介绍了一名40岁男性患者，患有右大腿近端平滑肌肉瘤，接受了手术切除和辅助放疗，大约一年后，为评估手术床和肿瘤进展进行盆腔磁共振成像（MR）检查时，发现右股骨头AVN，患者无症状。导致AVN的确切辐射剂量尚不清楚，且各研究结果不一，因此即使是无症状患者，也需要对放疗野内的关节进行谨慎研究，以便早期诊断并预防与延迟诊断相关的发病率。
