Laryngeal reconstruction following vertical partial laryngectomy.
Laryngeal reconstruction following vertical partial laryngectomy (VPL) with arytenoidectomy was studied in 30 dogs. Variations of a superiorly based thyroid cartilage flap (TCF) were used for reconstruction. In addition, sternohyoid muscle reconstruction and endolaryngeal muscle coverage were studied. Larynges were recovered after a 6-month period in 28 surviving dogs and were analyzed by endoscopic photographs and axial whole-organ sections. Endoscopic assessment (n = 18) demonstrated good results for arytenoid replacement (100%), pseudocord position (94%), pseudocord development (94%), and airway patency (100%). Arytenoid replacement was judged as completely (78%) or partially (22%) replaced. This was accomplished by a pseudocord extending to the cricoid in the horizontal plane. Pseudocord position was judged as normal (83%) or paramedian (11%), with the remainder lateralized (6%). Pseudocord development was judged as complete (72%) or partial (22%), with the remainder poor (6%). Reviewing both endoscopic photographs and gross sections (n = 28), airways were all normal without laryngeal or tracheal stenosis. Histologic assessment (n = 24) also demonstrated good results for arytenoid replacement (79%), pseudocord position (87%), and TCF survival in the glottic plane (79%). Arytenoid replacement was judged as complete (62%) or partial (17%), with the remainder poor (21%). Pseudocord position was judged as normal (50%) or paramedian (37%), with the remainder lateralized (13%). TCF survival was judged as total (63%) or partial (16%). Although not present in the glottic plane in the remaining cases (21%), a portion of the TCF was always present in the supraglottic region. The TCF was largely replaced by bone in the region of the pseudocord, and was covered by nonkeratinizing stratified squamous epithelium and a thick fibrous layer. Breakdown over the TCF was infrequent, with a small focus of granulation tissue over cartilage present in 1 (4%) of 24 cases. Clinically insignificant granulation tissue was present in a total of 6 (25%) cases. In the other 5 cases, this was over muscle or over permanent sutures. Focal cartilage necrosis was present in 2 (8%) of 24 cases, and was localized, self limiting, and deep to the endolaryngeal surface. When the TCF failed to survive histologically, poorer results for arytenoid replacement and pseudocord position generally resulted. However, this apparent difference was not statistically significant due to small sample sizes and variability in results. Other factors that may have kept this difference from becoming larger were thought to be contraction of th e normal cord towards the operated side with fore-shortening of the glottis, and medial rotation and ossification of the posterior thyroid ala remnant.(ABSTRACT TRUNCATED AT 400 WORDS)
Burgess
L P
LP
Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, Md.
D000818:Animals; D004285:Dogs; D006085:Graft Survival; D007825:Laryngectomy / Q000379:methods*; D007828:Laryngoscopy; D007830:Larynx / Q000473:pathology / Q000601:surgery; D009334:Neck Muscles / Q000601:surgery; D013524:Surgical Flaps / Q000379:methods*; D013957:Thyroid Cartilage / Q000473:pathology / Q000601:surgery