Histological Assessment of Plasma-Induced Tissue Sublimation Using the Plasma IQ Device: An Ex Vivo Morphometric...

Background: Minimally invasive aesthetic procedures using atmospheric plasma devices are increasingly applied to improve skin laxity and age-related loss of firmness. These systems generate a localized plasma arc at the tissue surface, enabling controlled and spatially confined tissue interaction; however, quantitative histological data on the extent of plasma-induced tissue effects remain limited. Materials and Methods: This ex vivo study evaluated freshly collected porcine kidney, liver, and skeletal muscle tissues (n = 3 per tissue type). Tissue sublimation defects were produced using the Plasma IQ device under conditions representative of standard clinical use, applying two predefined settings ("LOW" and "HIGH"). Immediately after treatment, specimens were fixed in 10% neutral buffered formalin and processed into formalin-fixed paraffin-embedded (FFPE) blocks. Sections were stained with hematoxylin and eosin (H&E), and the diameter and depth of the sublimation zones were measured by light microscopy. Results: Plasma IQ exposure consistently produced well-demarcated superficial sublimation defects in all tissues. The HIGH setting increased the diameter of the sublimation zones compared with the LOW setting across all tissue types, whereas the depth differences were smaller and tissue-dependent. Lesions exhibited a characteristic flattened, cone-shaped morphology, with diameter exceeding depth. No histologically detectable collateral damage was observed beyond the immediate sublimation zone. Conclusions: Atmospheric plasma treatment induces controlled and spatially confined tissue sublimation with clearly defined histological boundaries and limited penetration depth. These findings provide quantitative histological support for the localized tissue effects of plasma-based devices and their rationale in aesthetic procedures.