Cryoablation in the nose was rst described in the 1970s [13, 14], but its applicabil­ity to chronic rhinitis was limited due to lack of endoscopic visualization and ergo­nomically infeasible delivery of cryogen [14]. Cryotherapy works by ablating soft tissue, including underlying nerves, with a predictable depth of penetration. Because the arterial blood supply is only minimally impacted, risk of tissue necrosis is reduced. Nitrous oxide serves as the most commonly used cryogen and is stored in a cartridge that loads into a disposable handheld device (Fig.17.2). When triggered, the cryogen inates a closed-end probe which is laid against the target mucosa. Heat from surrounding tissue is pulled into the probe causing transient tissue freezing. A variable temperature distribution exists in the frozen and unfrozen regions, with the lowest temperatures experienced at the cold application site. The probe’s surface temperature reaches −80 to −60°C.This affords a transient therapeutic temperature of −20°C at a depth of 3 mm, which induces axonal damage while preserving the overlying mucosa viability. Freezing continues until heat provided by the body is in equilibrium to the heat extracted by the probe. The treatment is delivered at one or two non-overlapping positions in the PNN region.