F E Ucisik-Keser1, T L Chi1, Y Hamid2, A Dinh3, E Chang4, D Z Ferson5. 1. Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 1482, Houston, TX 77030-4000, USA. 2. Department of Anaesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, 1400 Holcombe Boulevard, Unit 0409, Houston, TX 77030-4000, USA. 3. Department of Anaesthesiology, The University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-0591, USA. 4. William Carey University College of Osteopathic Medicine, 498 Tuscan Avenue, Hattiesburg, MS 39401, USA. 5. Department of Anaesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, 1400 Holcombe Boulevard, Unit 0409, Houston, TX 77030-4000, USA dferson@mdanderson.org.
Abstract
BACKGROUND: Use of general anaesthesia or deep sedation during magnetic resonance imaging (MRI) studies leads to pharyngeal muscle relaxation, often resulting in snoring and subsequent vibrations with head micromotion. Given that MRI is very susceptible to motion, this causes artifacts and image quality degradation. The purpose of our study was to determine the effectiveness of different airway management techniques in overcoming micromotion-induced MRI artifacts. METHODS: After obtaining institutional review board approval, we conducted a retrospective study on the image quality of central nervous system MRI studies in nine patients who had serial MRIs under general anaesthesia. All data were obtained from electronic records. We evaluated the following airway techniques: use of no airway device (NAD); oral, nasal, or supraglottic airway (SGA); or tracheal tube. To assess MRI quality, we developed a scoring system with a combined score ranging from 6 to 30. We used the linear mixed model to account for patient-dependent confounders. RESULTS: We assessed 85 MRI studies from nine patients: 48 NAD, 27 SGA, four oral, four nasal, and two tracheal tube. Arithmetical mean combined scores were 21.6, 27.6, 20.3, 15.3, and 29.5, respectively. The estimated mean combined scores for the NAD and SGA cohorts were 22.0 and 27.3, respectively, showing that SGA use improved the combined score by 5.3 (P<0.0001). CONCLUSIONS: The use of an SGA during MRI studies under general anaesthesia or deep sedation significantly improves image quality.
BACKGROUND: Use of general anaesthesia or deep sedation during magnetic resonance imaging (MRI) studies leads to pharyngeal muscle relaxation, often resulting in snoring and subsequent vibrations with head micromotion. Given that MRI is very susceptible to motion, this causes artifacts and image quality degradation. The purpose of our study was to determine the effectiveness of different airway management techniques in overcoming micromotion-induced MRI artifacts. METHODS: After obtaining institutional review board approval, we conducted a retrospective study on the image quality of central nervous system MRI studies in nine patients who had serial MRIs under general anaesthesia. All data were obtained from electronic records. We evaluated the following airway techniques: use of no airway device (NAD); oral, nasal, or supraglottic airway (SGA); or tracheal tube. To assess MRI quality, we developed a scoring system with a combined score ranging from 6 to 30. We used the linear mixed model to account for patient-dependent confounders. RESULTS: We assessed 85 MRI studies from nine patients: 48 NAD, 27 SGA, four oral, four nasal, and two tracheal tube. Arithmetical mean combined scores were 21.6, 27.6, 20.3, 15.3, and 29.5, respectively. The estimated mean combined scores for the NAD and SGA cohorts were 22.0 and 27.3, respectively, showing that SGA use improved the combined score by 5.3 (P<0.0001). CONCLUSIONS: The use of an SGA during MRI studies under general anaesthesia or deep sedation significantly improves image quality.