Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Apr 8;17(2):eAO4533.
doi: 10.31744/einstein_journal/2019AO4533.

Experimental study for evaluation of a low-cost spray cryotherapy system

[Article in English, Portuguese]
Altair da Silva Costa Jr  1   2 , Andre Miotto  2 , Gustavo Andrade de Paulo  1 , Angelo Paulo Ferrari  1   2 , Luiz Hirotoshi Ota  2
Affiliations

Experimental study for evaluation of a low-cost spray cryotherapy system

[Article in English, Portuguese]
Altair da Silva Costa Jr et al. Einstein (Sao Paulo). .

Abstract
in English, Portuguese

Objective: To evaluate the feasibility and applicability of a low-cost cryotherapy system.

Methods: Experimental study with 25kg Landrace pigs submitted to a longitudinal cervico-thoraco-abdominal incision for exposure of the trachea, thorax and abdomen. The tissues were frozen by continuous spray application at different periods of time (5, 10 and 15 seconds). Spray cryotherapy was performed using a fluorinated gas (tetrafluorethane) delivered at - 47°C temperature (DermaFreeze®, Emdutos; ANVISA registration 80409950001; price R$ 394,00). via an adapted, disposable 1.8mm cholangiography catheter (Olympus; price R$ 280,00). The specimens were resected for histopathological analysis.

Results: Thirty samples were obtained from ten different organs and divided according to spray cryotherapy application time. System activation for 5, 10 or 15 seconds led to consumption of 14g, 27g and 40g of gas respectively (average gas consumption, 2.7g/s using a 1.8mm catheter). The system comprising a spray tube and catheter proved user-friendly and effective, with constant gas dispersion and adequate tissue freezing. In spite of effective freezing, microscopy failed to reveal tissue changes. This may have reflected methodological constraints precluding evaluation at tissue damage peak time (48 hours).

Conclusion: The low-cost spray cryotherapy system proved feasible and safe.

Objetivo: Avaliar a exequibilidade e a aplicação de um sistema de baixo custo de crioterapia.

Métodos: Estudo experimental realizado com um suíno da raça Landrace, 25kg, submetido à cervicotoracolaparotomia longitudinal, com exposição de traqueia, tórax e abdome. Procedemos ao congelamento das estruturas em tempos diferentes (5, 10 e 15 segundos) com jato contínuo. A crioterapia foi realizada com gás fluoretado (tetrafluoretano), na forma de spray em tubo, que atinge a temperatura de -47°C (DermaFreeze®, Emdutos; registro ANVISA 80409950001; preço R$ 394,00). A este tubo, adaptamos um cateter descartável de colangiografia de 1,8mm (Olympus; preço R$ 280,00). As peças foram ressecadas para análise histopatológica.

Resultados: Foram obtidas 30 amostras em 10 órgãos diferentes, divididos em três intervalos de tempo distintos. Quando o sistema foi acionado por 5 segundos, gastaram-se 14g de gás; por 10 segundos, 27g; e por 15 segundos, 40g; o gasto médio foi de 2,7g/s pelo cateter de 1,8mm. O sistema confeccionado com tubo de gás e cateter proporcionou resultado efetivo, com dispersão adequada e constante do gás, congelamento adequado e de fácil execução. Apesar da técnica evidenciar congelamento efetivo, na microscopia não houve alteração tecidual. Isso ocorreu porque o pico de lesão tecidual por congelamento ocorre após 48 horas, o que não foi possível avaliar por este método proposto.

Conclusão: O sistema de crioterapia em spray de baixo custo foi exequível e seguro.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest:

none.

Figures

Figure 1
Figure 1. Fluorinated gas tube (DermaFreeze®) and disposable endoscopic cholangiography catheter (PR-225Q/PR427G, 1.8mm, Olympus®)
Figure 2
Figure 2. Freezing technique applied to the pleura. (A) Catheter preparation and positioning. (B) Fluorinated gas spray application. (C) Immediate freezing results
Figure 3
Figure 3. Freezing and histology of esophagus (E), trachea (T) and lung (P) specimens
Figure 4
Figure 4. Histology of thawed larynx, stomach and small intestine tissue samples
Figure 5
Figure 5. Histological sections of the lung. (A) Not exposed to the gas. (B) Exposure time of 10 seconds. (C) Exposure time of 15 seconds
See this image and copyright information in PMC

References

    1. Benaglia MB, Jardim EC, Mendonca JC. Criocirurgia em odontologia: vantagens e desvantagens. Brazilian J Surg Clin Res. 2014;7(3):58–67.
    1. Moura-Netto C, Yamazaki AK, Cardoso LN, Cabrales RJ, Prokopowitsch I. Avaliação da temperatura mínima alcançada por cinco gases refrigerantes. Rev Inst Ciênc Saúde. 2007;25(4):403–405.
    1. Bhora FY, Ayub A, Forleiter CM, Huang CY, Alshehri K, Rehmani S, et al. Treatment of benign tracheal stenosis using endoluminal spray cryotherapy. JAMA Otolaryngol Head Neck Surg. 2016;142(11):1082–1087. - PubMed
    1. Dawber R. Cryosurgery: unapproved uses, dosages, or indications. Clin Dermatol. 2002;20(5):563–570. Review. - PubMed
    1. Moore RF, Lile DJ, Abbas AE. Current status of spray cryotherapy for airway disease. J Thorac Dis. 2017;9(S2) Suppl 2:S122–S129. Review. - PMC - PubMed

Publication types