Digital health · Neurocritical care
Piramidal
A foundation model trained on brainwave recordings, aimed at the intensive care unit. Two hospital collaborations are running, one retrospective pilot has been described, and no FDA authorization exists.
Two hours of squiggles
At Cleveland Clinic, an experienced technologist may spend up to two hours reviewing one 24 hour EEG recording. A physician then takes roughly 15 minutes to finalize the report. That is one patient, one bed, one day, and the hospital runs around 100 EEG devices across its intensive care units.
The recording never stops. The reading does. EEG in the ICU is reviewed in blocks every one to two hours, and reports often land every 12 or 24 hours. In the gap, a patient can seize unseen.
“This type of thing is time-consuming. It is subjective, and it is experience- and expertise-dependent,” says Imad Najm, the neurologist who directs the Epilepsy Center at Cleveland Clinic’s Neurological Institute.
Piramidal is a two person founding team with a $6 million seed and one claim: that a single model, trained on brainwaves the way a language model is trained on text, can read that day of EEG in seconds.
Why EEG resists automation
EEG has been in clinical use for about a century. It is cheap, it opens no one up, and it is the test that decides whether a comatose patient is quietly seizing. It is also still read by eye.
Three things make that hard to scale. Recordings run for days. The signal changes many times a second across a dozen or more channels. And patterns shift between people, by age, by skull thickness, by manufacturer, and by electrode placement.
A 2025 review of the field states the position bluntly: “expert visual interpretation remains the gold standard for clinical EEG evaluation even to this day.”
Piramidal has said since 2024 that manual review carries a margin of error of up to 30 percent. The figure appears in its Y Combinator launch post and in interviews. No underlying study is cited for it.
A physicist in a sleep lab
Dimitris Fotis Sakellariou started in physics. Three years in, a friend studying neuroscience in Edinburgh got him interested in the brain, and he began taking part in psychedelic and sleep studies that recorded his own EEG.
He went on to a PhD tied to the EEG department at St Thomas’ in London and is a King’s College London alum. PubMed lists four papers under his name between 2017 and 2021, on periodic discharges in postanoxic nonconvulsive status epilepticus, sleep spindles, dystonia, and software for brain network dynamics. Two co-authors from that work, Michalis Koutroumanidis and Mark Richardson, are now Piramidal advisors. He later spent four years at IQVIA shipping production AI.
Kris Pahuja came from product, at Spotify and then Google, where he worked with healthcare and education customers. They founded the company in 2023 and went through Y Combinator in the Winter 2024 batch.
Seed, pilots, and a hospital
In August 2024 they announced $6 million, and accounts of who led it do not agree. TechCrunch reported a round co-led by Adverb Ventures and Lionheart Ventures with Y Combinator participating. SiliconANGLE and HIT Consultant called it led by Y Combinator. The company site lists all three as leads. Angels include founders of Intercom, PlanGrid and Guilded.
Most of it went to GPUs. “Our raise was about 6 million and almost half of it is currently being spent towards compute,” Sakellariou said a month later.
The 2024 plan was four ICU pilots in the first quarter of 2025, plus two sites in England, King’s College and Saint Thomas’. No results from any have been published.
What replaced them is Cleveland Clinic, public since August 2025. By April 2026 the hospital had described a retrospective pilot and what it wants next: a central hub with a 98 inch screen, hundreds of beds feeding in, and the software pushing any bed where it sees a seizure to the front.
The one number
In that pilot the system showed approximately 90 percent sensitivity and 90 percent specificity for seizure detection and lateralization. Cleveland Clinic states that validation for the other patterns the software flags, such as periodic lateralized epileptiform discharges and triphasic waves, is still ongoing, and that the 90 percent figures cover seizures only.
That number has not appeared in a peer reviewed journal or a registered trial. Nor has anything else about the model.
What is proven, and what is still claimed
| Evidence | What the record shows | Source type |
|---|---|---|
| FDA authorization | No 510(k), PMA or De Novo record naming Piramidal as of Sep 24, 2026. Its April 2026 release states the models “are not cleared or approved by the U.S. Food and Drug Administration and are not intended for use in clinical decision-making at this time.” | Public record |
| Expected authorization | Cleveland Clinic wrote in April 2026 that the platform nears FDA approval, expected within months, supported by pilot data. Two weeks later the company release said the models are not cleared or approved. Nothing has since appeared in the FDA databases. | Partner claim, no record |
| Pilot accuracy | About 90 percent sensitivity and specificity for seizure detection and lateralization. Retrospective, one health system, annotated by three senior EEG readers and three physicians. Sample size unstated. | Partner-stated |
| Peer reviewed papers | None found. No PubMed record lists Piramidal as an affiliation. WIRED reported in 2025 that the company declined to give accuracy figures, said it had reached “humanlike” performance against a network of doctors, and planned to publish later. | Not found |
| Registered trials | No study naming Piramidal on ClinicalTrials.gov as of Sep 2026. | Not found |
| Training data | Company says the model uses public EEG datasets plus proprietary Cleveland Clinic data, and takes in nearly a million hours from tens of thousands of patients. Which corpora, under what licenses, is not stated. The best known clinical corpus, Temple University Hospital’s, holds 26,846 recordings and requires a signed access form. | Company-stated |
| “World first” framing | Axios and the American Hospital Association called the tool the world’s first AI model trained to read brainwaves. A July 2025 review already covered 10 EEG foundation models, and a January 2026 paper reviewed 55 and benchmarked 12 open ones. | Differs from literature |
| “Largest EEG model” | Founders say it is the largest model ever trained on EEG data. No parameter count, training set description or benchmark result has been released, so it cannot be checked. | Company-stated |
| Cleared competitors | Persyst 15 was cleared Dec 30, 2022 (K222002). Ceribell holds a run of clearances including the Status Epilepticus Monitor (K223504, May 2023) and Infant Seizure Detection Software (K252070, Nov 2025). Their seizure software class, product code OMB under 21 CFR 882.1400, dates to a 1987 clearance. The delirium class Ceribell entered in Dec 2025 came from a 2013 De Novo granted to Lexicor. | Public record |
Read plainly: Piramidal has a serious hospital collaborator, a real workflow problem, and one retrospective accuracy figure from that collaborator. It has no regulatory authorization, no registered study and no independent evaluation. The competitors selling seizure detection into the same ICUs have clearances and published validation behind them. That distance is the story.
What to watch
- An FDA submission of any kind. Cleveland Clinic said in April 2026 that authorization was months away.
- Publication of the pilot, with sample size, patient mix, and false positive behavior on live rather than stored recordings.
- Validation for the nonseizure patterns, still underway per Cleveland Clinic.
- A second funding round. Nothing has been announced since August 2024.
- The Cleveland Clinic Neurological Institute building, due in early 2027, where inpatient beds outside the epilepsy monitoring unit are to be wired for this.
In their words
“In the neural ICU, there are nurses actually monitoring the patient and looking for signs on the EEG. But sometimes they have to leave the room, and these are acute conditions,”
Kris Pahuja, co-founder, TechCrunch, 2024 · Independent
“It’s still the biggest EEG model that has ever existed, infinitely larger than anything else out there.”
Dimitris Fotis Sakellariou, CEO, TechCrunch, 2024 · Company-stated
“I was struck by the fact that it’s very, very easy to record brainwaves because you just stick a couple of wires in your head.”
Dimitris Fotis Sakellariou, Impact AI podcast, 2024 · Interview
“This serves as a proof of concept that using AI models will scale and create objectivity in live EEG monitoring, reading and interpretation,”
Imad Najm, MD, Cleveland Clinic Epilepsy Center, Consult QD, 2026 · Partner-stated
“The roles of our clinicians will shift from primary analysis to verification and final interpretation,”
Imad Najm, MD, Consult QD, 2026 · Partner-stated
“a big problem that keeps us awake at night”
Imad Najm, MD, on missed events, WIRED, 2025 · Independent
“model evaluations remain heterogeneous and largely limited, making it challenging to assess their practical off-the-shelf utility”
Wagh and colleagues, review of EEG foundation models, 2025 · Peer literature
Related companies
Sources
- Public recordFDA, ClinicalTrials.gov and PubMed queries for Piramidal, no records; four papers by D F Sakellariou
- Public recordSEC EDGAR full text search, no Form D naming Piramidal
- Public record510(k) records for Persyst (K222002) and Ceribell (K223504, K241589, K252070, K251936)
- Public recordDevice classification codes OMB and NCG, De Novo DEN110019
- Public recordThe Temple University Hospital EEG Data Corpus
- Peer literatureEEG Foundation Models: A Critical Review of Current Progress
- Peer literatureEEG-FM-Compass: Progress, Benchmarking, and Future Directions
- IndependentAn AI Model for the Brain Is Coming to the ICU
- IndependentPiramidal’s foundation model for brain waves could supercharge EEGs
- IndependentPiramidal raises $6M, reports naming Y Combinator as lead
- InterviewUnderstanding Brain Activity with Dimitris Sakellariou
- IndependentCeribell’s Status Epilepticus Software Receives FDA Clearance
- PartnerHarnessing AI to Bring Real-Time EEG Interpretation to the ICU
- CompanyIntraNerve Neuroscience and Piramidal Partner on EEG Monitoring
- CompanyPiramidal Inc. website, founders, advisors and investors
Profile researched and written by Healthcare Discovery. Last updated September 29, 2026.
