MANYETİK REZONANS GÖRÜNTÜLEMENİN VÜCUT ISISINA ETKİSİ

Abstract

Manyetik rezonans (MR) inceleme esnasında hastalar statik, gradyan ve radyofrekans (RF) elektromanyetik alanlara maruz kalırlar. Radyofrekans enerjisinin absorbsiyonunun doku ısısı artışlarına neden olduğu düşünülmektedir. Bu çalışmada 1.5 T MR görüntüleme esnasında vücut ısında oluşabilecek değişikliklerin saptanması amaçlanmıştır. Çalışmaya 21 ile 62 yaşları arasında (ortalama yaş 39±11.6 yıl) 34 kadın, 30 erkek toplam 64 hasta alınmıştır. Hastanın koltuk altı ısıları dijital termometre kullanılarak çekim öncesi ve sonrasında ölçülmüştür. Hastaların çekim öncesi koltuk altı ısıları ortalama 36.0±0.5 (34.8-37.1) OC iken, çekim sonrası ölçülen koltuk altı ısıları ortalama 36.4±0.5 (35.4-37.3) OC olarak bulunmuştur. Ortalama vücut ısı artışı; 0.4 ±0.3 (0.0-1.4) OC ve ortalama vücut ısısı artışı yüzdesi %1.1±0.8 (0.0-3.8) olarak saptanmıştır. Vücut ısılarında saptanan bu artışın istatistiksel olarak anlamlı olduğu görülmüştür (p<0.001). Sonuçlarımız özellikle termoregulasyonun etkilendiği düşünülen hastalarda MR görüntülemeleri sırasında dikkatli olmak gerektiğini düşündürmektedir. Yüksek alan gücüne sahip MR görüntüleme yöntemlerinin termofizyolojik etkilerini inceleyen ileri çalışmaların yürütülmesi gerektiği kanaatindeyiz. Dr. Özgür TOSUN, Dr. Karabekir ERCAN, Dr. Mustafa KARAOĞLANOĞLU

Keywords

• Manyetik Rezonans Görüntüleme
• radyofrekans enerjisi
• vücut ısısı

THE EFFECT OF MAGNETIC RESONANCE IMAGING ON BODY TEMPERATURE

Abstract

Patients are exposed to static, gradient and radiofrequency (RF) electromagnetic fields during magnetic resonance (MR) imaging. RF energy is believed to lead increases in tissue temperatures. This study aimed to determine the alterations in body temperature during 1.5 T MR imagings. A total of 64 patients of whom 34 were females and 30 were males aged between 21-62 (mean age 39±11.6 years) were included in the study. Armpit temperatures were measured by using a digital thermometer before and after imagings. Mean armpit temperatures of the patients before imaging was 36.0±0.5 (34.8-37.1) OC, while it was found as 36.4±0.5 (35.4-37.3) OC after imaging. Mean body temperature rise was 0.4 ±0.3 (0.0-1.4) 0C and mean body temperature rise percent was 1.1 ±0.8% (0.0-3.8). The detected rise in body temperature was statistically significant (p<0.001). Our results suggest that it is necessary to be careful during MR imaging especially in patients in whom thermoregulation is believed to be affected. We assume that further studies evaluating thermophysiological effects of higher magnetic field MR imaging procedures should be conducted

Keywords

• Magnetic resonance imaging
• radiofrequency energy
• body temperature

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