Injectable form of cross-linked hyaluronan is effective for middle ear wound healing.
OBJECTIVE
Two studies were designed to investigate a hyaluronan (HA) gel for middle ear (ME) wound healing.


METHODS
We used a guinea pig model of ME wound healing. In a long-term study, we performed a comparison of hearing and ME inflammation in 3 groups. Group 1 (n = 8) underwent bilateral wounding of ME mucosa and unilateral packing of the ME with HA gel (Sepragel). Group 2 (n = 6) was the same as group 1 except that the packing was absorbable bovine collagen sponges (Gelfoam). Group 3, the control group (n = 14), had operated, unpacked ears. In a short-term study, we investigated ME retention of HA gel at 1 and 2 weeks (n = 16).


RESULTS
At 1 week, all ears showed decreased distortion product otoacoustic emissions (DPOAEs) and auditory brain stem responses (ABRs) secondary to ME packing and postsurgical inflammation. The controls recovered preoperative DPOAEs and ABRs by week 2. Group 1 had decreased low-frequency DPOAEs at weeks 2 and 6, but their high-frequency DPOAEs and ABRs recovered to preoperative values by week 6. Group 2 had hearing losses that persisted throughout the study. Group 1 showed normal ME and inner ear histologic characteristics. Group 2 showed inflammatory cells within the ME and cochleas. Group 1 showed less packing retention than did group 2 at week 6 (p = .016). Eighty-five percent of the HA packing remained at 1 week, and 73% at 2 weeks.


CONCLUSIONS
Hyaluronan gel was a relatively safe and effective ME packing material in our animal model.
Angeli
Simon
S
University of Miami Ear Institute, University of Miami Miller School of Medicine, Miami, FL 33136-1015, USA.
Connell
Sarah
S
Gibson
Brian
B
Ozdek
Ali
A
McElveen
John T
JT
Van De Water
Thomas R
TR
D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000818:Animals; D001309:Auditory Threshold / Q000502:physiology; D003432:Cross-Linking Reagents; D004195:Disease Models, Animal; D004432:Ear, Middle / Q000293:injuries*; D005500:Follow-Up Studies; D005782:Gels; D006168:Guinea Pigs; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D007267:Injections; D013997:Time Factors; D016896:Treatment Outcome; D014945:Wound Healing / Q000187:drug effects*; D014947:Wounds and Injuries / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology
D000276:Adjuvants, Immunologic; D003432:Cross-Linking Reagents; D005782:Gels; D006820:Hyaluronic Acid