Kantor Birgit, Jorgensen Steven M, Lund Patricia E, Chmelik Michael S, Reyes Denise A, Ritman Erik L
Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA.
Scanning. 2002 Jul-Aug;24(4):186-90. doi: 10.1002/sca.4950240405.
A double-walled copper vessel, 32 cc in volume, was fabricated for scanning tissue specimens while maintained below freezing point. To keep specimen temperature within +/- 1 degrees C, temperature sensors within the chamber control, the rate of inflow of the cold nitrogen gas vented through the chamber. The specimen is attached to a small platform on top of a vertical pin which is attached to the computer-controlled rotating stage under the vessel. The purpose of this arrangement is to permit scanning of specimens up to 2 cm3 that (1) cannot be "fixed" (e.g., with formalin) because of analyses which are incompatible with prior fixation (certain immunohistochemistry and biomolecular methods), or (2) are "snap"-frozen during a transient process, such as the accumulation and/or washout of radiopaque indicators. Examples of "cryoscans" of porcine carotid and coronary artery wall opacification in either untouched or acutely stented arteries, snap-frozen immediately after selective intra-arterial injection of a contrast agent, show accumulation of contrast in the extravascular space indicating increased endothelial permeability or endothelial and medial disruption following stent placement. The detection of contrast in the adventitia suggest that vasa vasorum deliver the contrast agent from the main lumen to the adventitial extravascular space but not to the media.
制作了一个容积为32立方厘米的双层铜容器，用于在组织标本保持在冰点以下时进行扫描。为了将标本温度保持在±1摄氏度以内，腔室内的温度传感器控制通过腔室排出的冷氮气的流入速率。标本附着在垂直销顶部的一个小平台上，该垂直销连接到容器下方的计算机控制旋转台上。这种布置的目的是允许对体积达2立方厘米的标本进行扫描，这些标本：（1）由于与先前固定不兼容的分析（某些免疫组织化学和生物分子方法）而不能“固定”（例如用福尔马林），或（2）在瞬态过程中“速冻”，例如不透射线指示剂的积聚和/或洗脱。在选择性动脉内注射造影剂后立即速冻的未处理或急性支架置入的猪颈动脉和冠状动脉壁不透明化的“冷冻扫描”示例显示，血管外间隙中有造影剂积聚，表明支架置入后内皮通透性增加或内皮和中膜破坏。外膜中造影剂的检测表明，血管滋养管将造影剂从主腔输送到外膜血管外间隙，但不输送到中膜。
