The Quantitative EEG Engine
Behind SynDx Neurology
Transforming raw EEG into transparent, physician-verifiable neurophysiology measurements through fully deterministic signal processing — every metric is a traceable, reproducible computation.
How SynDx Converts EEG Into Quantitative Insight
Raw EEG flows through a seven-stage, fully deterministic neurophysiology pipeline — eleven transparent signal-processing modules, each a fixed formula with a clinical threshold. No machine learning, no probability guesses.
Clinical Workflow
From raw recording to a physician-signed report — six clear steps, every output verified.
Acquire EDF
A resting or clinical EEG is uploaded as a standard .edf file in the international 10-20 montage.
Preprocess
Bandpass filtering, ICA artifact removal, and adaptive epoching clean the signal automatically.
Quantify
Eleven deterministic qEEG modules compute every spectral metric, event, and quality measure.
Localize & Grade
Phase-reversal source localization, hemispheric symmetry, and transparent composite grading.
Generate Report
A structured six-section clinical decision-support report is assembled with full traceability.
Physician Review
A licensed neurologist verifies every flagged finding and exports the signed PDF.
Signal Processing Architecture
A fixed chain of transparent operations turns raw voltage into clean, analysis-ready signal — each step is a reproducible, inspectable computation.
Montage Standardization
Channel names mapped to the international 10-20 system — legacy labels (T3→T7, A1→M1) normalized automatically.
Bandpass · Notch · Avg Reference
FIR bandpass 0.5–70 Hz, 50 Hz notch, and average referencing condition every channel before analysis.
ICA Artifact Rejection
FastICA detects ocular and muscle components via kurtosis and variance heuristics, capped to avoid over-cleaning.
Adaptive Epoch Rejection
10 s epochs at 50% overlap; segments above an adaptive RMS threshold (5× median) are dropped from analysis.
Welch PSD Decomposition
Power spectral density partitioned into delta, theta, alpha, beta, and gamma bands per channel.
Double-Banana Bipolar Montage
Parasagittal and temporal bipolar chains enable polarity-reversal localization of epileptiform activity.
Core EEG Metrics
Every headline metric is a transparent measurement with an explicit clinical reference. Values shown are illustrative. Each is flagged against its threshold — not predicted by a model.
DAR
Within referenceDelta-Alpha Ratio
Slow-wave burden relative to alpha activity.
DTABR
Within reference(Delta+Theta) / (Alpha+Beta)
Global slowing index across the spectrum.
iPAF
Normal rangeIndividual Alpha Peak Frequency
Dominant background rhythm / organization.
BSI
MildBrain Symmetry Index
Interhemispheric spectral asymmetry.
SEF95
Light sedationSpectral Edge Frequency (95%)
Depth of sedation / consciousness.
SE
Normalized 0–1Spectral Entropy
Signal complexity (Shannon, normalized).
SR
LightSuppression Ratio
Share of suppressed epochs (RMS < 3 µV).
Grade
MildEncephalopathy Grade
Composite background-dysfunction score.
Spikes
NV-adjustedSharp-Transient Count
Epileptiform burden after normal-variant reduction.
Spectral Band Distribution
Relative band power · illustrativeEstimated phase-reversal focus — flagged for physician review
Spatial Analysis & Source Localization
SynDx maps where activity sits on the scalp — topographic power per band, an estimated epileptiform focus, and left-versus-right symmetry. These are measured distributions, not a modelled connectivity network.
Topographic Power Maps
Per-band relative power rendered across the 10-20 montage — delta, theta, alpha, and beta distributions at a glance.
Phase-Reversal Focus Localization
Polarity reversals across double-banana bipolar chains score each electrode to estimate an epileptiform focus.
Brain Symmetry Index
Interhemispheric spectral asymmetry over homologous electrode pairs, with left/right lateralization.
Deterministic Grading — No Black Box
Grades come from fixed formulas with published weights and thresholds. You can trace any result back to the exact factors that produced it.
Encephalopathy Composite Score
score = 0.35·DAR + 0.25·(no PDR) + 0.25·SR + 0.15·(1−iPAF)
Delta-Alpha Ratio (normalized)
Posterior dominant rhythm absent
Suppression ratio (normalized)
Background slowing factor
Each factor's contribution is emitted alongside the grade, so a clinician can see exactly why a study scored where it did.
Transparent Composite Scoring
Every grade decomposes into its exact weighted factors. No hidden weights, no opaque inference — the math is on the page.
Normal-Variant Reduction
Wicket spikes, mu rhythm, BETS, and lambda waves are reclassified out of the count, cutting false positives.
Worklist Review-Priority Triage
A triage label that orders the reading worklist by urgency. It is a workflow signal — never a diagnosis.
A Structured, Verifiable Report
Every run produces the same six-section deliverable — measurements, evidence images, and a worklist priority, all ready for physician sign-off.
- 1Recording Summary & Key MetricsGrade · Mild
- 2Detailed Quantitative Analysis7 panels
- 3Per-Channel Spectral Data19 ch
- 4Transient Events Log12 events
- 5aEEG Epoch-by-Epoch TrendCNV
- 6Electrode Positions10-20
Interactive Brain Map
Per-electrode spectral data rendered on a 10-20 map, focal channels highlighted in red.
Paginated Transient-Events Log
A filterable table of every detected spike and sharp wave with a normal-variant tag.
aEEG Trend & Topomap Evidence
Amplitude-integrated EEG trend plus delta/theta/alpha/beta topographic power maps.
Downloadable Signed PDF
The full six-section report exported for the chart after physician verification.
Where the Pipeline Is Used
One deterministic engine, adjunctive across the neurophysiology workflow.
Neurology & Clinical EEG
Automated quantitative EEG (qEEG) reporting for routine and clinical studies.
ICU & Critical Care
Encephalopathy grading, burst-suppression and suppression-ratio monitoring, aEEG continuity trends.
Epilepsy Screening
Interictal sharp-transient detection, phase-reversal localization, and photic/HV activation response.
SynDx Neurology
Bring Quantitative EEG to Your Clinic
Join our clinical network for early access to SynDx deterministic qEEG reporting.
SynDx Neurology is an adjunctive Clinical Decision Support tool. It does not diagnose, and all highlighted events and quantitative metrics must be independently verified by a licensed physician.