title: Intracranial facial nerve crush injury and facial motor nuclei cell loss in rats.
abstract: OBJECTIVE
  The purpose of this study was to (1) assess the degree of motoneuron cell loss and (2) the combinatorial effects of electrical stimulation (ES) and testosterone propionate (TP) on cell survival following an intracranial facial nerve crush injury and (3) compare these results to distal injuries.
  
  
  METHODS
  Prospective, randomized, controlled animal study.
  
  
  METHODS
  Sprague-Dawley rats were randomly divided into 3 groups: intracranial sham surgery or intracranial crush injury with or without ES and TP treatments. The intracranial sham group underwent exposure of the meatal segment of the right facial nerve. The intracranial crush groups underwent a crush of the meatal segment following exposure with or without ES and TP treatment immediately following the injury and followed for 8 weeks. Brain sections were thionin-stained, and facial motor nuclei (FMN) were counted using light microscopy. Results were compared to intratemporal and extracranial facial nerve crush injuries.
  
  
  RESULTS
  Intracranial crush injury resulted in a significant decrease in cell survival (n = 6) of 65.6% as compared to the sham group (99.4%; n = 9). The treatments increased cell survival to 93.8% (n = 2). The cell loss in the intracranial facial nerve injury is more substantial than the intratemporal (85.8%; n = 7) and extracranial (103.3%; n = 4) injuries.
  
  
  CONCLUSIONS
  Intracranial injury results in a more profound cell loss compared to the distal injuries. These data suggest a critical importance for the development of treatment modalities that can help improve cell survival following facial nerve injuries.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Loyola University Medical Center, Maywood, Illinois, USA mamine@lumc.edu.
authors.forename: Muhamad
authors.initials: M
authors.lastname: Amine
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Loyola University Medical Center, Maywood, Illinois, USA Research and Development Service, Edward Hines, Jr. VA Hospital, Hines, Illinois, USA.
authors.forename: Eileen M
authors.initials: EM
authors.lastname: Foecking
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Loyola University Medical Center, Maywood, Illinois, USA.
authors.forename: Sam J
authors.initials: SJ
authors.lastname: Marzo
mesh_terms: D000818:Animals; D002470:Cell Survival; D003131:Combined Modality Therapy; D016001:Confidence Intervals; D006259:Craniocerebral Trauma / Q000473:pathology / Q000628:therapy; D004195:Disease Models, Animal; D004558:Electric Stimulation / Q000379:methods*; D020220:Facial Nerve Injuries / Q000473:pathology* / Q000628:therapy*; D007150:Immunohistochemistry; D007279:Injections, Subcutaneous; D008297:Male; D009046:Motor Neurons / Q000473:pathology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function; D012016:Reference Values; D043343:Testosterone Propionate / Q000494:pharmacology*
chemical_list: D043343:Testosterone Propionate
keywords: cell survival; electrical stimulation; intracranial facial nerve crush injury; testosterone