14Atlas tools
Practical infrastructure: a working SP/AP calculator that applies all the cutoffs from the disease modules, a glossary of every term used in the atlas, the full references list with filtering, and the changelog.
FSP/AP ratio calculator
Enter measured SP and AP amplitudes (µV) below; the ratio is computed live and compared against the four published cutoffs from the disease modules. The ratio is electrode-independent — the same number from a tiptrode, TM, transtympanic, or intracochlear recording — so a value from any electrode site is directly comparable to the cutoffs.
The cutoffs the calculator applies, with their underlying evidence base:
| Cutoff | Value | Indication |
|---|---|---|
| Ferraro | SP/AP ≥ 0.40 | Classical threshold for hydrops on click ECochG (Module 5). |
| Gibson | SP/AP ≥ 0.30 | Alternative more-sensitive threshold preferred by Gibson and colleagues (Module 5). |
| Adams | SP/AP ≥ 0.34 | Superior canal dehiscence; 92.3% sens, 94% spec (Module 6). |
| Liberman range | SP/AP 0.35–0.60 | Group-level range reported in human cochlear synaptopathy; not an individual diagnostic (Module 11). |
The calculator computes the amplitude ratio and reports against the standard cutoffs. It does not account for the interpretive caveats covered throughout this atlas: AP shrinkage from severe hearing loss inflating the ratio (Module 5), interaural comparison adding diagnostic weight beyond the absolute number (Modules 5–7), the area-ratio measure that often outperforms amplitude (Module 5), or the basic question of whether the SP measurement is reliable in the first place (Module 4 checklist). Use the number, interpret with the modules.
FGlossary
Every term used in the atlas — from AP and CM to Bárány criteria, Berlin protocol, habenula perforata, otoferlin, and Tullio phenomenon — with a one-paragraph definition, a topic tag for filtering, and a link back to the module where the term is most relevant.
The full glossary lives at /glossary — searchable across both the term and the definition fields, with an alphabetical default sort and topic filters (anatomy, physiology, components, technique, diseases, diagnostics, measurements, eponyms). Individual entries are linkable by anchor (/glossary#sp-ap-ratio) for citation from external material.
Full references list
The peer-reviewed references that anchor the clinical claims throughout this atlas are maintained as a single typed registry (src/data/references.ts), with each entry recording authors, year, title, source, DOI/PMID, and Oxford CEBM evidence level where stated. Every <Cite refId="..."> in the atlas resolves against this registry at build time, so a missing id is a type error rather than a runtime surprise.
The full searchable references page lives at /references — sortable by year (descending by default), with substring search across authors, title, journal, atlas note, and refId, and DOI/PMID external links plus Oxford evidence-level badges where available.
Changelog
The atlas is versioned alongside the source repository. The current milestone is the Phase 1/2 port of the chat-built single-file HTML prototype to a Next.js 16 + React 19 static site on the MedLogicAI baseline, with the typed references registry, the canonical platform footer, and per-module pages established. Phase 3 introduces the interactive widgets (LIF plotter, rate-effect demonstrator, hydrops/third-window/polarity simulators, SP/AP calculator, CI insertion monitor, scenario-picker). Phase 4 introduces the trainer, compare tool, progress dashboard, print-all route, and the dedicated glossary and references pages.