Abbara Suhny, Migrino Raymond Q, Sosnovik David E, Leichter Jeffrey A, Brady Thomas J, Holmvang Godtfred
Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 100 Charles River Plaza, Ste. 400, Boston, MA 02114, USA.
AJR Am J Roentgenol. 2004 Mar;182(3):587-91. doi: 10.2214/ajr.182.3.1820587.
Arrhythmogenic right ventricular dysplasia (ARVD) is characterized by intramyocardial fibrofatty change. Fat suppression performed during conventional spin-echo imaging has been used to confirm fatty infiltration. The utility of fat suppression for enhancing the interpretation of studies of suspected ARVD has not previously been formally tested. We investigated the value of fat suppression for enhancing the interpretation of intramyocardial fatty infiltration.
Twenty-six consecutive patients clinically referred for evaluation of possible ARVD underwent cardiac MRI. Two independent observers reviewed the images retrospectively. Intramyocardial areas (n = 101) that had increased signal intensity relative to normal surrounding myocardium on T1-weighted conventional spin-echo images ("index areas") were identified. The index areas were interpreted for presence of fatty infiltration using two sets of images: The first set was obtained without fat suppression, and the second set was obtained with fat suppression. Agreement between reviewers and confidence of interpretation were determined and compared.
Interobserver agreement was measured using a 5-point scale: 1, definitely not fat; 2, probably not fat; 3, equivocal; 4, probably fat; and 5, definitely fat. The resulting kappa values were 0.35 for non-fat-suppressed images and 0.55 for fat-suppressed images. Interobserver kappa increased from 0.67 without fat suppression to 0.90 with fat suppression using a 3-point scale: 1, not fat; 2, equivocal; and 3, fat. Confidence in the diagnosis increased from 7.2 without fat suppression to 8.8 with fat suppression (p < 0.0001) on a 10-point scale ranging from 1, not confident, to 10, very confident.
The use of fat-suppressed in addition to non-fat-suppressed conventional T1-weighted spin-echo imaging increased interobserver agreement and confidence in diagnosis and evaluation of intramyocardial fatty infiltration in patients who were suspected to have ARVD.
致心律失常性右室心肌病（ARVD）的特征是心肌内纤维脂肪变性。传统自旋回波成像期间进行的脂肪抑制已被用于确认脂肪浸润。脂肪抑制在增强疑似ARVD研究解读方面的效用此前尚未经过正式测试。我们研究了脂肪抑制在增强心肌内脂肪浸润解读方面的价值。
连续26例因可能患有ARVD而接受临床评估的患者接受了心脏磁共振成像（MRI）检查。两名独立观察者对图像进行回顾性分析。在T1加权传统自旋回波图像上相对于正常周围心肌信号强度增加的心肌区域（n = 101）（“索引区域”）被识别出来。使用两组图像对索引区域进行脂肪浸润的解读：第一组图像未进行脂肪抑制，第二组图像进行了脂肪抑制。确定并比较观察者之间的一致性以及解读的可信度。
观察者间一致性采用5分制进行衡量：1分，肯定不是脂肪；2分，可能不是脂肪；3分，模棱两可；4分，可能是脂肪；5分，肯定是脂肪。未进行脂肪抑制的图像所得kappa值为0.35，进行脂肪抑制的图像所得kappa值为0.55。使用3分制时，观察者间kappa值从未进行脂肪抑制时的0.67增加到进行脂肪抑制时的0.90：1分，不是脂肪；2分，模棱两可；3分，是脂肪。在从1分（不自信）到10分（非常自信）的10分制中，诊断的可信度从未进行脂肪抑制时的7.2增加到进行脂肪抑制时的8.8（p < 0.0001）。
除了未进行脂肪抑制的传统T1加权自旋回波成像外，使用脂肪抑制可提高观察者间的一致性以及对疑似患有ARVD患者心肌内脂肪浸润的诊断和评估的可信度。
