Evaluation of spleen stiffness by 2D shear wave elastography for ruling out high risk varices in patients with chronic advanced liver disease. A systematic review and meta-analysis

Objectives: To systematically review the accuracy of spleen stiffness measurement (SSM) by 2D- Shear Wave Elastography (2D-SWE) in predicting high risk for bleeding varices (HRV) in cirrhotic patients. Methods: PubMed, Embase, Web of Science, Medline, Cochrane, and Google Scholar databases were searched up to 31/05/2023 for all human studies using 2D-SWE to estimate SSM and endoscopy to detect HRV. Meta-analysis was performed using a generalized linear mixed model. Publication bias was evaluated using the funnel plot asymmetry test. The Area Under the Summarized Receiver Operating Characteristic curve (AUSROC) was estimated using the "mada" package. Results: A total of 13 studies and 1970 patients were included. Of them, 27.8 % had HRV. The pooled sensitivity and polled specificity of SSM in detecting HRV were 90 % (95 %CI:87-92 %) and 68 % (95 %CI:58-77 %), respectively, with an AUSROC at 0.86 (95 %CI:0.82-0.90). The median cutoff value of SSM in detecting HRV was 34.2 kPa. In studies including exclusively HBV cirrhotic patients, SSM's polled sensitivity and specificity in predicting HRV was 88 % (95 %CI:82-92 %) and 73 % (95 %CI:68-78 %), respectively. The AUSROC was 0.84 (95 %CI:0.81-0.87). The number of repeated measurements per patient (<5 or >= 5) did not affect the method's capability. Using Aixplorer to evaluate SSM had a higher sensitivity in ruling out HRV than other 2D-SWE devices. Conclusions: Our meta-analysis supports that SSM by 2D-SWE has a good diagnostic performance for ruling out HRV in cirrhosis.