Huang M H, Lee S T, Rajendran K
Department of Plastic Surgery, Singapore General Hospital, Singapore.
Plast Reconstr Surg. 1998 Mar;101(3):613-27; discussion 628-9. doi: 10.1097/00006534-199803000-00007.
The purpose of this investigation was to apply the findings of an anatomic study of the levator veli palatini, palatopharyngeus, and superior constrictor muscles in 18 fresh cadaveric specimens of normal adults to analyze current controversies in velopharyngeal function and cleft palate surgery. The levator veli palatini was observed to form a muscular sling, suspending the velum from the cranial base. Its fibers occupied the middle 50 percent of the velum, lying in transverse orientation and without significant overlap across the midline. It is well placed to function as the prime mover in the velar component of velopharyngeal closure. The velar component of the palatopharyngeus consisted of two heads clasping the levator and inserting into the latter just short of the midline. Its pharyngeal component inserted into the superior constrictor in the lateral and posterior pharyngeal walls. Together, these two muscles formed a sphincter around the velopharyngeal port, suggesting that both muscles are involved in the pharyngeal component of velopharyngeal closure. Based on the premise that the goal of palatoplasty is to restore normal anatomy, the intravelar veloplasty has a sound basis, and theoretically improves both velar and pharyngeal wall function because it corrects the dysmorphology of both the levator and palatopharyngeus. Although the Furlow palatoplasty also reorients these velar muscles correctly in the transverse position, the resulting overlap of the levator and palatopharyngeus across the midline is morphologically abnormal. In addition, the use of large Z-plasty flaps in wide clefts may cause excessive lateral tension, increasing the risk of fistula formation and causing an impairment of velar stretch capacity. The raising of a vertical pharyngeal flap divides the fibers of the superior constrictor and has the potential to impair pharyngeal wall function. The sphincter pharyngoplasty interferes less with pharyngeal wall anatomy. The potential for an obstructive outcome seems to be related to the use of wide, long flaps and a tight, overlapping type of flap inset. In addition, the level of flap inset is important: an inset at the level of the uvula has the greatest risk of causing obstruction, whereas a higher inset at the level of attempted velopharyngeal closure seems to provide the best opportunity for achieving velopharyngeal competence while avoiding hyponasality and obstruction.
本研究的目的是将对18例正常成年新鲜尸体标本中的腭帆提肌、腭咽肌和咽上缩肌进行解剖学研究的结果应用于分析腭咽功能和腭裂手术中当前存在的争议。观察到腭帆提肌形成一个肌吊带，将软腭从颅底悬吊起来。其纤维占据软腭中部50%，呈横向排列，在中线处无明显重叠。它很适合作为腭咽闭合软腭部分的主要动力肌。腭咽肌的软腭部分由两个头组成，环抱腭帆提肌并在中线稍前方插入其中。其咽部部分插入咽侧壁和后壁的咽上缩肌。这两块肌肉一起在腭咽口周围形成一个括约肌，表明这两块肌肉都参与腭咽闭合的咽部部分。基于腭裂修复术的目标是恢复正常解剖结构这一前提，腭内腭成形术有合理的依据，并且理论上可改善软腭和咽壁功能，因为它纠正了腭帆提肌和腭咽肌的形态异常。尽管弗洛腭成形术也能使这些软腭肌肉在横向位置重新定向，但腭帆提肌和腭咽肌在中线处产生的重叠在形态上是异常的。此外，在宽腭裂中使用大的Z形皮瓣可能会导致过度的侧向张力，增加形成瘘管的风险，并导致软腭伸展能力受损。垂直咽瓣的掀起会分开咽上缩肌的纤维，有可能损害咽壁功能。括约肌咽成形术对咽壁解剖结构的干扰较小。出现阻塞性结果的可能性似乎与使用宽、长皮瓣以及紧密、重叠的皮瓣植入方式有关。此外，皮瓣植入的水平很重要：在悬雍垂水平植入皮瓣导致阻塞的风险最大，而在试图进行腭咽闭合的水平较高处植入皮瓣似乎为实现腭咽功能正常同时避免鼻音减退和阻塞提供了最佳机会。
