Sezer İlhan, Erdem Toslak İclal, Yağci Buket, Erbasan Funda, Ayan Ayşe, Karasu Uğur
Department of Physical Medicine and Rehabilitation, Division of Rheumatology, Akdeniz University Faculty of Medicine, Antalya, Turkey.
Department of Radiology, Antalya Training and Research Hospital, Antalya, Turkey.
Arch Rheumatol. 2019 Mar 28;34(4):371-379. doi: 10.5606/ArchRheumatol.2019.7120. eCollection 2019 Dec.
This study aims to evaluate gray-scale histogram analysis of B-mode ultrasound (US) images and US elastographic features of the parotid glands in patients with Sjögren's syndrome (SS) and to explore relationships with the ultrasonographic and disease activity scores in the light of histopathological findings.
A total of 57 consecutive female patients (mean age 47.9±10.4 years; range 25 to 76 years) with a diagnosis of SS and 48 healthy female individuals (mean age 51.1±10.8 years; range 20 to 70 years) underwent parotid ultrasonography and real-time tissue elastography imaging. Quantitative measurements of gray-scale US images were performed using the histogram software of the scanner. The histogram ratios of the parotid glands from both sides were obtained (histogram ratio; mean gray-scale histogram parotid/mean gray-scale histogram fat). Strain ratio (SR; ratio of fat to gland parenchyma) was calculated from the color-coded images. Subjective B-mode US scoring of electronically recorded gray- scale US images was performed by two radiologists independently for intra- and inter-observer agreement. Subjective assessments, quantitative measurements, and clinical parameters were compared.
The SR of the patient group (1.4±0.8 right side, 1.5±0.9 left side) was significantly higher than that of the control group (1.0±0.3 right side, 1.1±0.3 left side) (p<0.05). The gray-scale histogram ratio of the patient group (1.3±0.5 right side, 1.4±0.9 left side) was lower than that of the control group (1.8±0.7 right side, 1.9±0.7 left side) (p<0.05). Receiver-operating-characteristics curve yielded 66% sensitivity for both sides and 50% and 52% specificity for the right and left sides, respectively, for a cut-off SR of 1.02; 76% and 86% sensitivity for the right and left sides, respectively, and 63% specificity for both sides for a cut-off histogram ratio of 1.35. The quantitative histogram ratio method had a higher positivity rate for the diagnosis of abnormal parotid glands than subjective assessments of US images.
Sonoelastography and gray-scale histogram analysis of the parotid glands may be used as auxiliary tools to detect parotid gland sonographic abnormalities in patients with SS.
本研究旨在评估干燥综合征（SS）患者腮腺的B型超声（US）图像灰度直方图分析及US弹性成像特征，并结合组织病理学结果探讨其与超声及疾病活动评分的关系。
连续纳入57例诊断为SS的女性患者（平均年龄47.9±10.4岁；范围25至76岁）和48例健康女性个体（平均年龄51.1±10.8岁；范围20至70岁），对其进行腮腺超声检查及实时组织弹性成像。使用扫描仪的直方图软件对灰度US图像进行定量测量。获取双侧腮腺的直方图比值（直方图比值；腮腺平均灰度直方图/脂肪平均灰度直方图）。从彩色编码图像计算应变比值（SR；脂肪与腺实质的比值）。由两名放射科医生独立对电子记录的灰度US图像进行主观B型US评分，以评估观察者内和观察者间的一致性。比较主观评估、定量测量和临床参数。
患者组的SR（右侧1.4±0.8，左侧1.5±0.9）显著高于对照组（右侧1.0±0.3，左侧1.1±0.3）（p<0.05）。患者组的灰度直方图比值（右侧1.3±0.5，左侧1.4±0.9）低于对照组（右侧1.8±0.7，左侧1.9±0.7）（p<0.05）。对于截断SR为1.02，受试者工作特征曲线显示双侧敏感性为66%，右侧和左侧特异性分别为50%和52%；对于截断直方图比值为1.35，右侧和左侧敏感性分别为76%和86%，双侧特异性为63%。定量直方图比值法诊断腮腺异常的阳性率高于US图像的主观评估。
腮腺的超声弹性成像和灰度直方图分析可作为检测SS患者腮腺超声异常的辅助工具。
