The Missing Stoichiometry of Edema A Self-Case Radiographic Observation of Pseudo-Gaseous Components in Acute Inammation

We report a self-case radiographic observation of a subtle diminution in retrocalcaneal radiolucency within a two-hour interval following administration of intramuscular dexamethasone (10 mg) and oral ketoprofen (150 mg) for mild Achilles tendon discomfort. Comparative analysis of both ankles before medication, and of the affected left tendon pre- and post-treatment, shows a rapid reduction in radiolucent signal temporally coupled with complete resolution of pain. We argue that this observation is more parsimoniously explained by the presence of a gaseous phase — microbubbles of CO2 generated locally by unbuffered acid-base neutralization between lysed-cell acidic contents (pH<7.0) and extravasated alkaline plasma (pH≈7.35–7.45) — than by a purely fluid model of inflammatory edema. The hypothesis rests on undisputed biochemistry, specifically the bicarbonate buffer equation catalyzed by ubiquitous tissue carbonic anhydrase: H++HCO3−⇌H2CO3⇌H2O+CO2↑ This model explains a kinetic anomaly that the fluid-only model cannot: gas clears in minutes via diffusion and pulmonary elimination, while interstitial fluid requires hours to days for lymphatic drainage. A concrete falsifiable prediction follows: high-resolution MRI of acutely inflamed tissue should reveal small signal voids consistent with gas, absent in chronic or post-treatment controls. The wider implication is a case of Framework Lock: a stoichiometrically predicted product (CO2) has been omitted from the standard edema model without chemical justification. We invite falsification rather than endorsement.