Histomorphometric and laryngeal videostroboscopic analysis of the effects of corticosteroids on microflap healing in the dog larynx

The histologic and functional effects of unilateral, layered corticosteroid s on lateral microflap healing in 15 dogs were analyzed. Histologic section s of steroid-treated vocal folds (VFs) were studied with computer morphomet ry to examine differences in the tissue healing response. Paired analysis r evealed increases in the inflammatory infiltrate around the microflap in th e steroid-treated VFs at 2, 4, and 6 weeks (6.3%, 30.6%, and 34.9%, all wit h p <.02). The neovascular response in the steroid-treated VFs was less at 2 weeks (-20.9%, p <.005) but greater at 4 and 6 weeks (16.3% and 4.3%, p < .005). To better characterize the effect of steroids on the healing process , a normal, time-dependent distribution was applied to the histologic data and demonstrated a delay in the steroid-treated VF tissue response of 12 da ys for the inflammatory infiltrate and 21 days for the neovascular response . Qualitative and quantitative analysis of in vivo laryngeal videostrobosco py (LVS) samples taken preoperatively and at sacrifice could not identify s ignificant differences in appearance, amplitude, mucosal wave, or supplenes s between the 2 VFs. Therefore, although corticosteroids cause a delay in w ound healing, LVS does not discern differences in microflap characteristics between healing steroid-treated and control VFs at 2, 4, or 6 weeks. If st eroids are used, the surgeon should account for a probable delay in wound h ealing, but should not expect an overall difference in functional outcome.