Chen C Y, Chen F H, Lee C C, Lee K W, Hsiao H S
Department of Radiology, Tri-Service General Hospital, Taipei, Taiwan, Republic of China.
AJNR Am J Neuroradiol. 1998 Oct;19(9):1631-5.
Differential considerations for pineal region CSF collections include both true cysts and normal cystlike anatomic variations. Our purpose was to determine the sonographic characteristics of pineal region fluid spaces that reflect the presence of a normal persistent cavum velum interpositum (CVI).
Eighteen neonates and infants who had sonographic findings of "cysts" in the pineal region were examined prospectively with conventional sonography and color Doppler sonography to evaluate the shape of the fluid collection and its anatomic relationship with the color-coded internal cerebral veins. Subsequent MR images were obtained in eight of these infants to determine the exact nature of the cystlike collections.
The cystlike spaces in the pineal region were of an inverted helmet shape in 14 subjects and roundish in four. All were situated inferior or slightly anteroinferior to the splenium of the corpus callosum and 2.5 to 4 mm away from the quadrigeminal plate. The internal cerebral veins were either inferior (n = 12) or inferolateral (n = 6) to the cystlike spaces at sonography. Subsequent MR studies confirmed eight of these cystlike spaces to be the posterior portion of the CVI.
The CVI may appear as a cyst in the pineal region on neonatal sonograms. Usually, it has a characteristic inverted helmet shape and is situated beneath the fornices and above the internal cerebral veins.
松果体区脑脊液聚集的鉴别诊断需考虑真性囊肿和正常的囊肿样解剖变异。我们的目的是确定松果体区液性间隙的超声特征，以反映正常持续存在的中间帆腔（CVI）的存在。
对18例松果体区有“囊肿”超声表现的新生儿和婴儿进行前瞻性常规超声和彩色多普勒超声检查，以评估液性聚集区的形态及其与彩色编码的大脑内静脉的解剖关系。其中8例婴儿随后接受了磁共振成像检查，以确定囊肿样聚集区的确切性质。
14例松果体区囊肿样间隙呈倒头盔形，4例呈圆形。所有囊肿样间隙均位于胼胝体压部下方或稍前下方，距四叠体板2.5至4毫米。超声检查时，大脑内静脉位于囊肿样间隙下方（12例）或下外侧（6例）。随后的磁共振成像研究证实其中8个囊肿样间隙为中间帆腔的后部。
中间帆腔在新生儿超声检查中可能表现为松果体区的囊肿。通常，它具有特征性的倒头盔形状，位于穹窿下方和大脑内静脉上方。
