以量化超音波紋理參數分析不同疾病活動度下僵直性脊椎炎患者之關節著骨點

目的：僵直性脊椎炎（Ankylosing Spondylitis，AS）的疾病活動度對患者造成廣泛的影響，高疾病活動度可能導致更多器官系統的炎症，使治療更為複雜，甚至提高死亡率。著骨點炎症是AS特徵性症狀之一，其對於AS的診斷和疾病活動監測非常重要，因此，本研究探討超音波結合紋理特徵參數在不同疾病活動狀態下的AS患者著骨點處之差異，旨在通過紋理特徵參數的變化來提供醫師一個新的臨床指標，以更精確地評估和監控 AS 患者的病情，從而提升治療策略的效率及最終改善疾病管理。材料與方法：本研究招募35位AS患者，並根據僵直性脊椎炎疾病活動評分-C反應蛋白（ASDAS-CRP）將患者分為兩組進行分析，當ASDAS-CRP < 1.3時，判定為疾病不活躍組，共有17位患者；若ASDAS-CRP ≥ 1.3，則為疾病活躍組，共有18位患者。此外，參與者需完成多項問卷調查，並接受超音波掃描以評估10處肌腱韌帶著骨點，再圈選每個著骨點上2-3mm的範圍進行灰階亮度以及九個紋理參數的分析，所得之數據進行統計分析用以探討兩組之間的關係。結果：在對10個肌腱韌帶著骨點進行超音波掃描中，特別是在右手肱骨外上髁的共同伸展肌腱和右腳跟骨的阿基里斯腱處，發現顯著的紋理參數差異。具體來說，在這兩處著骨點中，與疾病不活躍組相比，疾病活躍組的均質性、能量以及歸一化逆差異動量的數值略高，而對比度、熵和差異度則顯著較低，並且在統計學上都有顯著的差異，代表可以利用紋理參數區分活躍期及不活躍期。最後，通過將對比度數值與問卷數據結合進行線性判別分析，此方法不僅無須抽血，也進一步提升了區分疾病活動狀態的能力。結論：本研究確認了AS患者在常用的右側肢體中，著骨點的病變較為常見，但是傳統超音波影像在識別這些輕微病變方面難以直接看出差異，然而，超音波紋理參數分析在臨床上評估AS的病變程度及疾病活動狀態顯示了強大的應用潛力。另外，結合對比度和問卷的線性判別分析能更精確地評估疾病的活動狀態，並提供一種無需抽血的策略，幫助臨床醫師區分疾病的活躍期與非活躍期。

Objective：Ankylosing Spondylitis (AS) has a profound impact on patients' overall health, with high disease activity potentially leading to inflammation in multiple organ systems, complicating treatment, and even increasing mortality rates. Enthesitis is one of the hallmark symptoms of AS, playing a crucial role in the diagnosis and disease activity monitoring of AS. This study investigates the differences in enthesis sites among AS patients with varying disease activity levels using ultrasound combined with texture feature parameters. The goal is to provide physicians with a novel clinical indicator through the changes in texture feature parameters, enabling more precise assessment and monitoring of AS patients' conditions.Material and method：This study recruited 35 AS patients and grouped them using the Ankylosing Spondylitis Disease Activity Score-C Reactive Protein (ASDAS-CRP). Patients with ASDAS-CRP < 1.3 were classified as the inactive disease group (17 patients), and those with ASDAS-CRP ≥ 1.3 were classified as the active disease group (18 patients). Additionally, patients completed multiple questionnaires. Ultrasound was used to scan 10 tendon and ligament enthesis sites, and a 2-3mm area around the enthesis was selected for grayscale brightness and texture parameter analysis. The resulting values were then statistically analyzed to observe the relationships between the two groups.Results：In ultrasound scanning of 10 entheses, significant textural parameter differences were observed, especially at the common extensor tendon of the right humeral epicondyle and the Achilles tendon of the right calcaneus. Specifically, compared to the inactive disease group, the active disease group exhibited slightly higher values in homogeneity, energy, and normalized inverse difference moment, while contrast, entropy, and variance were significantly lower, all showing statistically significant differences. These findings indicate that textural parameters can differentiate between active and inactive phases of the disease. Finally, by combining contrast values with questionnaire data for linear discriminant analysis, this method not only obviates the need for blood draws but also enhances the ability to discriminate disease activity states.Conclusion：This study confirmed that enthesopathy is more common in the frequently used right limbs of patients with AS. However, traditional ultrasound imaging often fails to directly identify these subtle lesions. In contrast, ultrasound texture parameter analysis demonstrates significant potential for assessing the extent of lesions and the activity status of AS in a clinical setting. Additionally, combining contrast analysis with questionnaire data in linear discriminant analysis allows for a more accurate assessment of the disease activity state. This approach provides a non-invasive strategy, aiding clinicians in differentiating between active and inactive phases of the disease without the need for blood draws.