Subtle Medical

Subtle Medical is a healthcare technology company that applies deep learning to the acquisition stage of medical imaging. Its vendor-neutral software improves image quality on both standard and accelerated scan protocols, allowing hospitals and imaging centers to shorten exam times and increase scanner throughput without buying new hardware. Products include SubtleHD(MR), which uses denoising and increased sharpness to enable up to 80% faster MRI sequences across existing scanners; SubtleHD(PET), which enables up to 75% faster PET scans with commercial radiotracers on PET, PET/CT and PET/MR systems; and SubtleHD(CT), which reduces noise and improves low-contrast detectability on existing CT and PET/CT scanners. The earlier flagship products SubtleMR and SubtlePET were the first of their kind to receive FDA clearance, in 2018 and 2019 respectively, and are also CE-marked.

The portfolio has expanded into a broader multi-modality suite. The Subtle-ELITE suite bundles SubtleHD(MR), SubtleSYNTH (AI-powered synthetic image generation) and SubtleALIGN. Other products include SubtleREFORMAT for MRI data harmonization and quality standardization, AiMIFY for AI-enhanced contrast developed with Bracco, and SubtleGAD, a pipeline technology for lowering gadolinium dose in contrast-enhanced MRI. The company also markets an imaging hub, a unified platform intended to give health systems a single point of control for imaging performance across scanners from different manufacturers and across MRI, PET and CT environments.

As of 2026 the company reported 11 FDA clearances, more than 25 peer-reviewed publications, over 30 issued and/or pending patents, more than $85 million raised, over 75 full-time employees and deployment on more than 1,300 scanners internationally.

Founding story

Subtle Medical was born out of Stanford University. Enhao Gong, a deep learning scientist with a PhD in Electrical Engineering from Stanford, was studying under Greg Zaharchuk, a neuroradiologist and professor of radiology at Stanford, when they identified a shared interest in improving the quality and accessibility of medical imaging and the potential of deep learning to do so. The company was founded in 2017, was accepted into the Stanford StartX program, and holds exclusive licensing rights to technology the founders developed at Stanford in 2016.

Business model

Subtle Medical commercializes its AI software through multiple models: SaaS subscriptions and software systems sold to hospitals and imaging centers, and contracted arrangements with medical imaging equipment manufacturers (such as Siemens Healthineers) and pharmaceutical companies (such as Bayer and Bracco) that embed or leverage Subtle's AI platform. Software overlays existing scanner fleets, with images copied and processed in the cloud, so customers do not need to replace hardware.

Software revenue from SaaS and software-system licensing to imaging providers, plus OEM and pharmaceutical partnership contracts. The company described SaaS scalability across large imaging networks and, in 2024, tens of millions of dollars of contracts secured from radiology providers worldwide.

Traction

As of 2026, deployments on more than 1,300 scanners worldwide, 11 FDA clearances, more than 25 peer-reviewed papers and over 75 full-time employees. In October 2025 the company projected 2.5x annualized U.S. revenue growth for 2025, with more than 600 U.S. installations and well over 1,000 globally. In July 2024 it reported serving more than 600 sites globally and 2.5 million patients annually with a sustained 2x year-over-year growth rate. Reported customer outcomes include up to 80% faster scans, 50%+ higher throughput and, per the incoming CEO, roughly four to five additional MRI patient slots per scanner per day above a typical U.S. baseline of about 14.

Latest developments

On June 2, 2026 Subtle Medical announced $33 million in growth capital anchored by a Series C led by funds managed by Morgan Stanley Expansion Capital, with Shinhan Venture Investment and existing investors Fusion Fund, EnvisionX, BRV and Samsung Ventures participating, bringing total capital raised to $86 million; the funds are earmarked for product development, global commercial expansion and scaling its vendor-neutral platform across MRI, PET and CT. Concurrently, Ohad Arazi was appointed CEO, succeeding co-founder Enhao Gong, who became chief science officer while continuing to lead the scientific roadmap and China operations. The company also received FDA clearance for SubtleHD(PET) on May 27, 2026 and for SubtleHD(CT) on June 10, 2026, and in 2025 launched the Subtle-ELITE suite and was named to TIME's World's Top HealthTech Companies of 2025.