Transtemporal ultrasound application potentially elevates brain temperature: results of an anthropomorphic skull model.
Ultraschall Med
; 34(1): 51-7, 2013 Feb.
Article
de En
| MEDLINE
| ID: mdl-22872379
ABSTRACT
PURPOSE:
Transtemporal sonothrombolysis is a tool for a more effective treatment in acute stroke patients. However, some reports revealed side effects, which might be potentially connected to temperature elevation. To gain better insight into cerebral temperature changes during transtemporal sonication, diagnostic and therapeutic ultrasound (US) applications were evaluated using an anthropomorphic skull model. MATERIALS ANDMETHODS:
The impact of diagnostic (PW-Doppler, 1.8-MHz, 0.11 W/cm², TIC 1.2) and therapeutic (1-MHz and 3-MHz, 0.07 - 0.71 W/cm², continuous and pulsed mode) US application on temperature changes was evaluated at the level of muscle/temporal bone (TB), TB/brain, brain and at the middle cerebral artery (MCA) using 4 miniature thermocouples along the US beam. Sonication lasted 120 minutes.RESULTS:
Diagnostic ultrasound revealed a maximum temperature increase of 1.45°/0.60°/0.39°/0.41°C (muscle/TB, TB/brain, brain, MCA) after 120 minutes. Therapeutic-1-MHz ultrasound raised temperature by 4.33°/2.02°/1.05 °C/0.81°C (pulsed 120) and by 10.38°/4.95°/2.43°/2.08°C (pulsed 15) over 120 minutes. Therapeutic-3-MHz US raised temperature by 4.89°/2.56°/1.24/1.25°C (pulsed 120) and by 14.77°/6.59°/3.56°/2.86°C (pulsed 15) over 120 minutes, respectively. Continuous application of therapeutic US (1-MHz and 3-MHz) led to a temperature increase of 13.86°/3.63°/1.66°/1.48°C and 17.09°/4.28°/1.38/0.99°C within 3 minutes.CONCLUSION:
Diagnostic PW-Doppler showed only a moderate temperature increase and can be considered as safe. Therapeutic sonication is very powerful in delivering energy so that even pulsed application modes resulted in significant and potentially harmful temperature increases.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Ultrasonothérapie
/
Régulation de la température corporelle
/
Encéphale
/
Infarctus cérébral
/
Échographie-doppler transcrânienne
/
Fantômes en imagerie
/
Thrombose intracrânienne
/
Thrombolyse mécanique
/
Chauffage
Limites:
Humans
Langue:
En
Journal:
Ultraschall Med
Année:
2013
Type de document:
Article
Pays d'affiliation:
Autriche