Comparisons of steroid, acyclovir, lipoprostoglandin E1 and steroid + acyclovir treatments in facial paralysis: a rat study.
OBJECTIVE
To induce experimental peripheral facial paralysis by inoculation of HSV1 and to compare the effects of steroid, acyclovir, lipoprostoglandin E2 and steroid + acyclovir treatments in terms of clinical recovery, electrophysiologically and histopathologically.


METHODS
A total of 132 adult female rats were used in this study. HSV type 1 strain was inoculated at the back of the left ear by using 27 gauge needle. Of all animals, 70 (53%) rats which developed facial paralysis were divided into five groups (n = 14 for each group) as control, steroid + acyclovir, lipoprostaglandin E1, steroid only and acyclovir only. At the end of the 21 days period, the rats were clinically examined and electrophysiological tests were performed, then decapitated and the nerve specimens were obtained.


RESULTS
A modified electroneurography (ENoG) test was performed and the latencies and the amplitudes were compared. The findings of the intact side were better, but with no significant difference. Histopathologicaly edema was significantly smaller in all groups compared to the controls (p < 0.05). Similarly, no difference was seen in terms of vacuolar degeneration and Schwann cell hyperchromatisation among the groups and no significant difference in recovery period and rate of facial paralysis when all groups were compared.


CONCLUSIONS
Facial paralysis induced by HSV1 recovered spontaneously within a week. In the treatment of facial paralysis, steroid alone, acyclovir alone, steroid + acyclovir, or lipoprostaglandin E1 all reduced edema in the infected facial nerve but there was no statistical difference in of the rate or degree of recovery.
Gök
Uzeyir
U
Firat University, Medical Faculty, Otorhinolaryngology Department, Elaziğ, Turkey.
Alpay
Hayrettin Cengiz
HC
Akpolat
Nusret
N
Yoldaş
Tahir
T
Kilic
Abdullah
A
Yilmaz
Bayram
B
Kabakuş
Nimet
N
D000212:Acyclovir / Q000008:administration & dosage / Q000627:therapeutic use*; D000527:Alprostadil / Q000008:administration & dosage / Q000627:therapeutic use*; D000704:Analysis of Variance; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D020330:Bell Palsy / Q000150:complications / Q000188:drug therapy* / Q000821:virology; D004195:Disease Models, Animal; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D004594:Electrophysiology; D005154:Facial Nerve / Q000473:pathology / Q000503:physiopathology; D005158:Facial Paralysis / Q000188:drug therapy / Q000209:etiology / Q000821:virology; D005260:Female; D018259:Herpesvirus 1, Human / Q000472:pathogenicity; D015994:Incidence; D007273:Injections, Intramuscular; D007274:Injections, Intraperitoneal; D008776:Methylprednisolone Hemisuccinate / Q000008:administration & dosage / Q000627:therapeutic use*; D011379:Prognosis; D051381:Rats; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use*
D000893:Anti-Inflammatory Agents; D014665:Vasodilator Agents; D008776:Methylprednisolone Hemisuccinate; D000527:Alprostadil; D000212:Acyclovir