Background: Osteoradionecrosis (ORN) of the jaw is a severe, progressive complication of radiation therapy for head and neck malignancies. ORN features radiologically overlaps osteomyelitis and tumor recurrence. This study analyzes jaw ORN imaging characteristics and progression and proposes an ORN CT-based grading system that builds on current ClinRAD grades.Materials and Methods: A retrospective cohort study of 35 patients with biopsy-proven or clinically diagnosed ORN following radiation therapy. Initial and follow-up imaging were assessed to evaluate the radiological evolution of ORN. The imaging findings were statistically analyzed using IBM SPSS v26, and literature comparisons were made.Results: The median onset of ORN post-radiotherapy was 27–28 months (range: 2–119 months). The most common clinical presentations included non-healing ulcers (49%), pain (34%), and discharging sinuses (31%). Mandibular involvement was predominant (51%), with focal bone alterations being more frequent (63%). CT findings at clinical suspicion of ORN included resorption (100%), erosions (100%), sclerosis (86%), and fragmentation (83%). Follow-up imaging showed increased bone erosion (77%), fragmentation (92%), and sclerosis (92%). A CT-based grading system is proposed to classify ORN progression.Conclusions: ORN follows a predictable radiological progression, beginning with trabecular resorption and cortical erosion, leading to fragmentation and sequestrum formation. The proposed grading system provides a structured approach for early diagnosis. The proposed grading system provides a structured approach for diagnosis. Larger studies of imaging analyses are required to validate these findings and refine diagnostic criteria.
背景：颌骨放射性骨坏死（ORN）是头颈部恶性肿瘤放射治疗后一种严重且进行性的并发症。其影像学特征与骨髓炎及肿瘤复发存在重叠。本研究分析了颌骨ORN的影像学特征及进展过程，并在现有ClinRAD分级基础上，提出了一种基于CT的ORN分级系统。 材料与方法：对35例经活检证实或临床诊断为放射治疗后ORN的患者进行回顾性队列研究。通过评估初始及随访影像资料，分析ORN的影像学演变过程。使用IBM SPSS v26软件对影像学结果进行统计分析，并与文献进行比较。 结果：ORN的中位发病时间为放疗后27-28个月（范围：2-119个月）。最常见的临床表现包括不愈合溃疡（49%）、疼痛（34%）和瘘管形成（31%）。下颌骨受累为主（51%），局灶性骨质改变更为常见（63%）。临床怀疑ORN时的CT表现包括骨吸收（100%）、骨侵蚀（100%）、骨质硬化（86%）和骨碎裂（83%）。随访影像显示骨侵蚀（77%）、骨碎裂（92%）和骨质硬化（92%）程度增加。本研究提出了一种基于CT的分级系统以评估ORN进展。 结论：ORN遵循可预测的影像学进展规律，始于骨小梁吸收和皮质骨侵蚀，进而发展为骨碎裂和死骨形成。所提出的分级系统为早期诊断提供了结构化方法。未来需要更大规模的影像学分析研究以验证这些发现并完善诊断标准。
Decoding Osteoradionecrosis of the Jaw: Radiological Progression and a Novel CT-Based Grading System
肿瘤(癌症)患者之家