Novel Artificial Intelligence Guided Non-expert Compression Ultrasound Deep Vein Thrombosis Diagnostic Pathway May Reduce Vascular Laboratory Venous Testing.

Abstract

Ultrasonography and D dimer testing are established modalities for evaluating potential lower extremity deep vein thrombosis (DVT). The ThinkSono Guidance system is an artificial intelligence (AI) based software allowing non-ultrasound trained providers to perform compression ultrasounds for evaluation by remote interpreters. This study evaluated its clinical use and potential reduction of venous duplexes and waiting times. Patients with suspected DVT were prospectively recruited through the institution's emergency department. Patients underwent an AI guided two region proximal DVT compression examination by non-ultrasound trained providers using the ThinkSono Guidance system and D dimer testing. Ultrasound images remotely reviewed by the on call radiologist were rated for diagnostic quality; all images of sufficient quality were assessed as either "Compressible/no proximal DVT" or "Inadequate imaging/possible DVT". All patients assessed as "compressible" with negative D dimers were discharged. All other patients were sent for a venous duplex scan. Time to diagnosis, sensitivity, and specificity of ThinkSono Guidance against D dimers and full duplex scans were calculated. Fifty three patients (mean age 56 ± 18 years, 45% female) were scanned with ThinkSono Guidance by one of three non-ultrasound trained providers. All scans were of diagnostic quality. ThinkSono Guidance with radiologist review yielded 45 negative DVT diagnoses (85%). Seventeen of these with negative D dimers were discharged (32%) and 28 required duplex ultrasound testing per trial protocol (23 due to positive D dimers, five due to D dimer non-availability). All of these duplexes were negative (100% sensitivity). Eight patients were suspected of having DVT by the reviewing radiologist, and duplex confirmed DVT in six patients (96% ThinkSono Guidance specificity, 36% D dimer specificity). ThinkSono Guidance scans averaged 6.75 minutes for scan and review. The median time from scan initiation to review was 37.5 minutes. This study suggested that a significant proportion of patients with suspected DVT could safely avoid duplex ultrasound and D dimer testing using the ThinkSono system, setting the basis for a novel AI assisted diagnostic pathway.