Reidenbach M M
Institute of Anatomy, Rheinische Friedrich-Wilhems-University, Bonn, Germany.
Clin Anat. 1998;11(1):9-21. doi: 10.1002/(SICI)1098-2353(1998)11:1<9::AID-CA2>3.0.CO;2-R.
A precise definition of clinically important laryngeal regions and compartments is still a matter of controversy. The often neglected subglottic area was reinvestigated in plastinated serial sections of 21 human adult specimens. The superior border of the subglottic region is defined by the transition of squamous stratified epithelium covering the vocal cords into the respiratory epithelium of the caudal airways. It is found at the inferior margin of the vocal fold at variable distance from the free edge of the vocal cord and bears a high risk of carcinogenesis. The anterior border of the subglottic region is the cricothyroid space between the thyroid cartilage and cricoid arch. Medially, it is bridged by the median cricothyroid ligament. Laterally, the gap between thyroid and cricoid cartilage is filled by adipose tissue in most cases. This provides a broad connection of intra- and extralaryngeal connective tissue. There, cancer may escape the larynx. The conus elasticus is often regarded as a firm fibroelastic membrane within the subglottic region, but its structure may be disturbed by piercing blood vessels or age-related changes, facilitating cancerous spread. The cricoid lamina representing the dorsal border of the subglottic space ossifies preferentially in its superior part, which is often attacked by tumor invasion. The inferior border of the subglottic region is defined at the inferior rim of the cricoid cartilage. At this level, the endocricoid submucosal tissue contains loosely arranged collagenous fibers, which probably do not act as an anatomic barrier.
临床上重要的喉部区域和腔室的精确界定仍存在争议。在21例成人标本的塑化连续切片中，对常被忽视的声门下区域进行了重新研究。声门下区域的上边界由覆盖声带的复层鳞状上皮向尾侧气道的呼吸上皮的过渡来界定。它位于声带襞的下缘，距声带游离缘有可变距离，且具有较高的癌变风险。声门下区域的前边界是甲状软骨和环状软骨弓之间的环甲间隙。在中线，它由环甲正中韧带连接。在外侧，甲状腺和环状软骨之间的间隙在大多数情况下被脂肪组织填充。这为喉内和喉外结缔组织提供了广泛的连接。在那里，癌症可能会扩散到喉部以外。弹性圆锥通常被视为声门下区域内的一层坚韧的纤维弹性膜，但其结构可能会因穿通血管或与年龄相关的变化而受到干扰，从而促进癌性扩散。代表声门下间隙背侧边界的环状软骨板优先在其上部骨化，该部位常受到肿瘤侵犯。声门下区域的下边界在环状软骨的下缘界定。在此水平，环状软骨黏膜下组织含有排列疏松的胶原纤维，这些纤维可能不作为解剖学屏障。
