Clinical evaluation of cryosurgery for vascular lesions in the oral cavity

Efficacy of cryogun cryotherapy for benign oral vascular anomalies: a longitudinal study

OBJECTIVES

To evaluate the efficacy and safety of cryogun cryotherapy in treating benign oral vascular anomalies (BOVAs).

MATERIALS AND METHODS

We conducted a retrospective longitudinal study on patients with BOVA who underwent cryogun cryotherapy. The clinical outcomes assessed included lesion regression, recurrence, complications, and clinical predictors of prognosis.

RESULTS

Cryogun cryotherapy demonstrated high efficacy in treating BOVA in a study of 33 patients, with 97% of lesions achieving complete regression after an average of 1.64 ± 0.93 sessions (range: 1-4). Treatment outcomes were influenced by factors such as lesion morphology and anatomical location. Lesions in the buccal mucosa required more sessions compared to other anatomical sites, and exophytic lesions necessitated more sessions than flat lesions.

CONCLUSIONS

Cryogun cryotherapy is a safe and effective treatment option for BOVA, regardless of lesion size or location. Residual lesions can be treated successfully with additional sessions.

CLINICAL RELEVANCE

Cryogun cryotherapy offers a reliable prognosis for BOVA patients and provides a cost-effective, non-invasive alternative to other treatment methods.

Histological evaluation of tissue destruction in mouse tongues caused by cryosurgery

Introduction

Cryosurgery is recognized as a treatment option for various types of oral lesions. Although cryosurgery is less invasive and easier to perform than surgical treatments, adverse events, such as stomatitis and scarring can occur if the freezing is excessive. There are few studies regarding the effects of cryosurgery on the surrounding soft tissues. Thus, this study investigated the extent of tissue destruction and healing progress in tongues of mice who underwent cryosurgery.

Methods

Eight-week-old male BALB/c mice were used. An instrument cooled with liquid nitrogen was lightly touched on the right side of the tongue for 5 s, and a second test was performed 10 s later. Histological evaluation was performed 3, 7, and 14 days after cryosurgery. Blood vessels were evaluated with India ink at 1, 3, 7, 14, and 21 days after cryosurgery.

Results

Destruction of the soft tissue spread to the left side of the tongue after 3 days. At 7 days, it was confirmed that the muscle tissue was in the process of repair and was completely repaired at 14 days. Although blood vessels were not confirmed at 3 days, they were visible after seven days and were confirmed at 21 days all over the tongue.

Discussion and Conclusion

These results indicated that the tissue destruction caused by cryosurgery was extensive and suggest that the duration and frequency of freezing should be minimized for clinical use.

Lay Summary

Cryosurgery is a treatment method for various types of oral lesions. Freezing the lesion causes the tissue to collapse, resulting in its disappearance. Although cryosurgery is less invasive and easier to perform than surgical treatments, adverse events, such as stomatitis and scarring can occur if the freezing is excessive. This study investigated the extent of tissue destruction and healing progress in tongues of mice who underwent cryosurgery.The right side of mice tongues were frozen by an instrument cooled with liquid nitrogen for 5 s, and a second test was performed 10 s later. The tissue destruction was evaluated at 3, 7, and 14 days after freezing. Blood vessels were evaluated with India ink at 1, 3, 7, 14, and 21 days after freezing. Tissue destruction spread to the left side of the tongue after 3 days. At 7 days, it was confirmed that the muscle tissue was in the process of repair and was completely repaired at 14 days. Blood vessel repair was confirmed at 21 days in the throughout tongue. These results indicated that the tissue destruction caused by cryosurgery was large and suggest that the duration and frequency of freezing should be minimized for clinical use.

Biomolecular Pathways of Cryoinjuries in Low-Temperature Storage for Mammalian Specimens

Low-temperature preservation could effectively extend in vitro storage of biological materials due to delayed or suspended cellular metabolism and decaying as illustrated by the Arrhenius model. It is widely used as an enabling technology for a variety of biomedical applications such as cell therapeutics, assisted reproductive technologies, organ transplantation, and mRNA medicine. Although the technology to minimize cryoinjuries of mammalian specimens during preservation has been advanced substantially over past decades, mammalian specimens still suffer cryoinjuries under low-temperature conditions. Particularly, the molecular mechanisms underlying cryoinjuries are still evasive, hindering further improvement and development of preservation technologies. In this paper, we systematically recapitulate the molecular cascades of cellular injuries induced by cryopreservation, including apoptosis, necroptosis, ischemia-reperfusion injury (IRI). Therefore, this study not only summarizes the impact of low-temperature preservations on preserved cells and organs on the molecular level, but also provides a molecular basis to reduce cryoinjuries for future exploration of biopreservation methods, materials, and devices.