Background Real-time sonoelastography (SElasto) is used to examine tissue elasticity. Chronic inflammation and fibrosis of major salivary glands leads to reduced saliva production in patients with primary Sjögren’s syndrome (pSS).
Objectives To investigate the value of SElasto to detect pSS patients with reduced saliva production
Methods Prospective study on 38 pSS patients fulfilling the American-European consensus group criteria [mean age 58 years; 92% female; median duration of sicca symptoms 6 years, 65% histological sialadenitis] and 11 healthy controls. B-mode sonography and SElasto of parotid and submandibular glands was performed using a GE Logiq E9 ultrasound device. Parenchymal homogenicity, echogenicity, hypoechogenic areals, hyperechoic reflections and clearness of glandular borders were semiquantitatively scored (total score ranging from 0-48) (1). SElasto was used to examine the elasticity of glandular parenchyma and a semiquantitative rating was performed with 0=no, 1=up to 25%, 2=up to 50%, 3=up to 75% and 4=more than 75% hardened areas within the salivary gland. The total score ranged from 0 to 16. Clinical assessments were performed at the same day of sonographic evaluation and included: Saxon test, Schirmer test, Xerostomia inventory (XI), and the Ocular Surface Disease Index (OSDI). Statistical analysis was performed using SPSS program (v18.0) and the Mann-Whitney-U and Spearman rank correlation test were performed as appropriate. Interobserver variability of sonography was tested in 30% of pSS patients by intraclass correlation coefficient (ICC).
Results pSS patients had higher B-mode scores [median 25 (range 2.0-44.0) vs. 2.0 (0-8.0), p<0.001] and SElasto scores [6.0 (2.0-12.0) vs. 3.0 (1.0-4.0), p<0.001] than healthy controls.
pSS patients showed a median salivary flow rate of 1.69 g/2min (range 0.31-3.79), a median moisture on the filter paper (Schirmer test) of 4.0mm/5min (0-50.0), a median XI of 27.5 (8.0-43.9) and an median OSDI of 43.8 (0-77.1). In pSS patients, an inverse correlation was found between the result of the Saxon test and SElasto score (corrcoeff -0.426, p=0.009), whereas B-mode ultrasound results were not associated with saliva production. Neither disease duration nor duration of sicca symptoms influenced ultrasound results.
A good reproducibility of B-mode and SElasto results was found as indicated by an ICC of 0.926 (95%CI 0.565-0.983) and 0.934 (0.787-0.981), respectively.
Conclusions Increased rigidity of major salivary glands as demonstrated by SElasto in patients with pSS correlates with the impairment of saliva secretion.
Hocevar A, Ambrozic A, Rozman B, Kveder T, Tomsic M. Ultrasonographic changes of major salivary glands in primary Sjogren’s syndrome. Diagnostic value of a novel scoring system. Rheumatology 2005;44:768-72.
Disclosure of Interest None Declared