[Middle ear packing with collagen-polyvinylpyrrolidone sponge. Experimental study in guinea pigs].
BACKGROUND
Packing material is mandatory in middle ear (ME) surgery in order to avoid inflammation, adhesions and fibrotic healing. Collagen polivynil-pirrolidone (CPVP) is a healing modulator, which reduces inflammation and fibrosis. Hence we can hypothesize that packing of the ME with CPVP sponge will lead a good ME healing.


OBJECTIVE
The aim of this study was to evaluate the otoscopic and microscopic changes induced on the healthy mucosa of the ME and Tympanic membrane (TM) after packing with CPVP sponge in guinea pigs.


METHODS
Twelve guinea pigs were operated on of right myringotomy. The ME was packed with: Group I (n = 6): Absorbable gelatin sponge (AGS) in SS; Group II (n = 6): CPVP soaked in SS. TM and ME integrity was evaluated otoscopically, as well as residual packing material. Euthanasia was performed on the 4th post-operative week. ME mucosa histologic examination was done.


RESULTS
Group I in all the cases showed residual packing material (p < 0.007 Student's test p < 0.001 ANOVA). Histologically both groups presented inflammation with polymorphonuclears, in addition group I showed severe lymphocytosis (p < 0.003 Student's, test p < 0.001, ANOVA).


CONCLUSIONS
The CPVP sponge when it is used as material of packing in the OM of guinea pigs produces less chronic inflammatory changes, but more studies with the injured mucosa are required to validate their utility in the otologic surgery.
Olmos-Zúñiga
Raúl
R
Departamento de Cirugía Experimental, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, México, DF. raolzu@yahoo.com
González-López
Rosalva
R
Gaxiola-Gaxiola
Miguel
M
Jasso-Victoria
Rogelio
R
Sotres-Vega
Avelina
A
Santibáñez-Salgado
Alfredo
A
Soda-Merhy
Antonio
A
D000818:Animals; D003094:Collagen / Q000494:pharmacology*; D004432:Ear, Middle / Q000187:drug effects* / Q000473:pathology*; D006168:Guinea Pigs; D009092:Mucous Membrane / Q000187:drug effects / Q000473:pathology; D038781:Otoscopy; D011205:Povidone / Q000494:pharmacology*; D015503:Surgical Sponges
C120488:collagen-PVP; D003094:Collagen; D011205:Povidone