Not all pulmonary emboli are thrombotic. NTPE spans septic, tumor, fat, air, and iatrogenic causes, often mimicking PE but requiring different management. Recognizing key imaging clues + clinical context is critical for timely, lifesaving diagnosis.
Nonthrombotic pulmonary artery embolism (NTPE) involves occlusion of pulmonary arteries by nonthrombotic material, such as septic emboli, tumor cells, fat, air, or foreign substances. NTPE is less common than thrombotic pulmonary embolism (PE) and may be misdiagnosed as PE. Although the clinical manifestation mimics that of PE, NTPE has distinct pathophysiologic mechanisms that necessitate different management. Diagnosis requires a high index of clinical suspicion and knowledge of imaging findings. The authors provide an overview of the various causes of NTPE, including infectious, neoplastic, iatrogenic or exogenous, and miscellaneous entities, and highlight their key imaging findings. Early and accurate diagnosis is essential for appropriate management.
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decay, particularly from tritium: Because the neutrino carries away part of the decay energy, a nonzero neutrino mass slightly modifies the spectrum of emitted electrons. Precision experiments such as KATRIN have pushed this method to its limit, setting an upper bound of about 0.45 eV on the neutrino mass [1]. While KATRIN uses molecular tritium gas, new strategies aim to go further by embedding tritium in engineered materials.