Mirowitz S A, Gutierrez F R
Department of Radiology, Jewish Hospital, Washington University Medical Center, St. Louis, MO 63110.
Radiology. 1992 Jan;182(1):231-3. doi: 10.1148/radiology.182.1.1727288.
Results of 20 random cardiac spin-echo and cine gradient-echo magnetic resonance (MR) imaging examinations were reviewed for nodular and/or linear soft-tissue structures projecting from the right atrial wall. A nodular soft-tissue structure (mean diameter, 6 mm) isointense with myocardium was observed along the posterior atrial wall in 18 of 20 patients (90%). The structure extended between the orifices of the superior and inferior venae cavae. Linear strand-like projections originating from the structure coursed across the atrial chamber in 5 of 20 patients (25%). Similar findings were present in one patient who underwent cardiac surgery for a suspected atrial mass. The region of nodular thickening was shown histologically to represent myocyte hypertrophy and fibrosis. The nodular and linear structures correlated anatomically with the crista terminalis muscle bundle and Chiari network, respectively. These structures are frequently visualized on cardiac MR images, are of variable prominence, and may closely simulate the appearance of tumor or other cardiac masses in some patients. Awareness of the location and MR imaging features of these structures will help prevent misdiagnosis.
回顾了20例随机心脏自旋回波和电影梯度回波磁共振（MR）成像检查的结果，以观察从右心房壁突出的结节状和/或线状软组织结构。在20例患者中的18例（90%）中，沿心房后壁观察到一个与心肌等信号的结节状软组织结构（平均直径6mm）。该结构延伸至上、下腔静脉口之间。20例患者中有5例（25%），源自该结构的线状条索状投影穿过心房腔。一名因疑似心房肿块接受心脏手术的患者也有类似表现。组织学显示，结节状增厚区域代表心肌肥厚和纤维化。结节状和线状结构在解剖学上分别与终嵴肌束和奇阿里网相关。这些结构在心脏MR图像上经常可见，突出程度不一，在一些患者中可能酷似肿瘤或其他心脏肿块。了解这些结构的位置和MR成像特征将有助于防止误诊。
