Facial Nerve Axonal Analysis and Anatomical Localization in Donor Nerve

Optimizing Axonal Load for Cross-Facial Nerve Grafting in Facial Reanimation

Austin Hembd, Purushottam A. Nagarkar, Salim Saba, Dinah Wan, J. Walter Kutz, Brandon Isaacson, Sachin Gupta, Charles L. White, Rod J. Rohrich, Shai M. Rozen

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Background: Donor nerve axonal count over 900 in two-stage reconstructions using cross-facial nerve grafts is possibly associated with improved outcomes in facial reanimation. Facial nerve axonal analysis was performed to determine the ideal location for optimizing axonal load. Correlation of axonal number, branch diameter, and age was also assessed. Methods: Twenty-eight fresh unpreserved cadaveric hemifaces were dissected exposing the extracranial facial nerve branches. Axonal counts at 2-cm intervals from the pes anserinus along branches inserting into the zygomaticus major muscle were taken, noting position relative to the zygomatic arch, posterior ramus border, lateral border of the zygomaticus muscle, and anterior parotid gland border. Nerves were fixed, sectioned, and stained with SMI-31 antineurofilament stain for digital axonal analysis. Results: All specimens had one or more intraparotid zygomatic branches with over 900 axons, and 96 percent had an extraparotid branch with over 900 axons. The likelihood that a zygomatic branch would have over 900 axons at its last intraparotid point (mean, 6 mm posterior to the parotid border) was 92 percent (range, 67 to 100 percent) in contrast to 61 percent (range, 25 to 100 percent) when sampled at the first extraparotid point (mean, 14 mm anterior to the parotid border). Nerve cross-sectional area was positively correlated to its axonal count (R° = 78 percent; p < 0.0001), with nerve diameter over 0.6 mm predicting over 900 axons. Age did not correlate with axonal counts. Conclusions: Branches with adequate axonal load were found in all specimens. The likelihood of adequate branch selection improved from 61 percent to 92 percent with short retrograde intraparotid dissection. Nerve diameter correlated with axonal load.

Original languageEnglish (US)
Pages (from-to)177-183
Number of pages7
JournalPlastic and reconstructive surgery
Volume139
Issue number1
DOIs
StatePublished - Jan 1 2017
Externally publishedYes

Fingerprint

Facial Nerve
Axons
Zygoma
Muscles
Parotid Gland
Dissection
Coloring Agents
Transplants

ASJC Scopus subject areas

  • Surgery

Cite this

Facial Nerve Axonal Analysis and Anatomical Localization in Donor Nerve : Optimizing Axonal Load for Cross-Facial Nerve Grafting in Facial Reanimation. / Hembd, Austin; Nagarkar, Purushottam A.; Saba, Salim; Wan, Dinah; Kutz, J. Walter; Isaacson, Brandon; Gupta, Sachin; White, Charles L.; Rohrich, Rod J.; Rozen, Shai M.

In: Plastic and reconstructive surgery, Vol. 139, No. 1, 01.01.2017, p. 177-183.

Research output: Contribution to journalArticle

Hembd, Austin ; Nagarkar, Purushottam A. ; Saba, Salim ; Wan, Dinah ; Kutz, J. Walter ; Isaacson, Brandon ; Gupta, Sachin ; White, Charles L. ; Rohrich, Rod J. ; Rozen, Shai M. / Facial Nerve Axonal Analysis and Anatomical Localization in Donor Nerve : Optimizing Axonal Load for Cross-Facial Nerve Grafting in Facial Reanimation. In: Plastic and reconstructive surgery. 2017 ; Vol. 139, No. 1. pp. 177-183.
@article{339101a86661401f9d85a6c59092dc78,
title = "Facial Nerve Axonal Analysis and Anatomical Localization in Donor Nerve: Optimizing Axonal Load for Cross-Facial Nerve Grafting in Facial Reanimation",
abstract = "Background: Donor nerve axonal count over 900 in two-stage reconstructions using cross-facial nerve grafts is possibly associated with improved outcomes in facial reanimation. Facial nerve axonal analysis was performed to determine the ideal location for optimizing axonal load. Correlation of axonal number, branch diameter, and age was also assessed. Methods: Twenty-eight fresh unpreserved cadaveric hemifaces were dissected exposing the extracranial facial nerve branches. Axonal counts at 2-cm intervals from the pes anserinus along branches inserting into the zygomaticus major muscle were taken, noting position relative to the zygomatic arch, posterior ramus border, lateral border of the zygomaticus muscle, and anterior parotid gland border. Nerves were fixed, sectioned, and stained with SMI-31 antineurofilament stain for digital axonal analysis. Results: All specimens had one or more intraparotid zygomatic branches with over 900 axons, and 96 percent had an extraparotid branch with over 900 axons. The likelihood that a zygomatic branch would have over 900 axons at its last intraparotid point (mean, 6 mm posterior to the parotid border) was 92 percent (range, 67 to 100 percent) in contrast to 61 percent (range, 25 to 100 percent) when sampled at the first extraparotid point (mean, 14 mm anterior to the parotid border). Nerve cross-sectional area was positively correlated to its axonal count (R° = 78 percent; p < 0.0001), with nerve diameter over 0.6 mm predicting over 900 axons. Age did not correlate with axonal counts. Conclusions: Branches with adequate axonal load were found in all specimens. The likelihood of adequate branch selection improved from 61 percent to 92 percent with short retrograde intraparotid dissection. Nerve diameter correlated with axonal load.",
author = "Austin Hembd and Nagarkar, {Purushottam A.} and Salim Saba and Dinah Wan and Kutz, {J. Walter} and Brandon Isaacson and Sachin Gupta and White, {Charles L.} and Rohrich, {Rod J.} and Rozen, {Shai M.}",
year = "2017",
month = "1",
day = "1",
doi = "10.1097/PRS.0000000000002897",
language = "English (US)",
volume = "139",
pages = "177--183",
journal = "Plastic and Reconstructive Surgery",
issn = "0032-1052",
publisher = "Lippincott Williams and Wilkins",
number = "1",

}

TY - JOUR

T1 - Facial Nerve Axonal Analysis and Anatomical Localization in Donor Nerve

T2 - Optimizing Axonal Load for Cross-Facial Nerve Grafting in Facial Reanimation

AU - Hembd, Austin

AU - Nagarkar, Purushottam A.

AU - Saba, Salim

AU - Wan, Dinah

AU - Kutz, J. Walter

AU - Isaacson, Brandon

AU - Gupta, Sachin

AU - White, Charles L.

AU - Rohrich, Rod J.

AU - Rozen, Shai M.

PY - 2017/1/1

Y1 - 2017/1/1

N2 - Background: Donor nerve axonal count over 900 in two-stage reconstructions using cross-facial nerve grafts is possibly associated with improved outcomes in facial reanimation. Facial nerve axonal analysis was performed to determine the ideal location for optimizing axonal load. Correlation of axonal number, branch diameter, and age was also assessed. Methods: Twenty-eight fresh unpreserved cadaveric hemifaces were dissected exposing the extracranial facial nerve branches. Axonal counts at 2-cm intervals from the pes anserinus along branches inserting into the zygomaticus major muscle were taken, noting position relative to the zygomatic arch, posterior ramus border, lateral border of the zygomaticus muscle, and anterior parotid gland border. Nerves were fixed, sectioned, and stained with SMI-31 antineurofilament stain for digital axonal analysis. Results: All specimens had one or more intraparotid zygomatic branches with over 900 axons, and 96 percent had an extraparotid branch with over 900 axons. The likelihood that a zygomatic branch would have over 900 axons at its last intraparotid point (mean, 6 mm posterior to the parotid border) was 92 percent (range, 67 to 100 percent) in contrast to 61 percent (range, 25 to 100 percent) when sampled at the first extraparotid point (mean, 14 mm anterior to the parotid border). Nerve cross-sectional area was positively correlated to its axonal count (R° = 78 percent; p < 0.0001), with nerve diameter over 0.6 mm predicting over 900 axons. Age did not correlate with axonal counts. Conclusions: Branches with adequate axonal load were found in all specimens. The likelihood of adequate branch selection improved from 61 percent to 92 percent with short retrograde intraparotid dissection. Nerve diameter correlated with axonal load.

AB - Background: Donor nerve axonal count over 900 in two-stage reconstructions using cross-facial nerve grafts is possibly associated with improved outcomes in facial reanimation. Facial nerve axonal analysis was performed to determine the ideal location for optimizing axonal load. Correlation of axonal number, branch diameter, and age was also assessed. Methods: Twenty-eight fresh unpreserved cadaveric hemifaces were dissected exposing the extracranial facial nerve branches. Axonal counts at 2-cm intervals from the pes anserinus along branches inserting into the zygomaticus major muscle were taken, noting position relative to the zygomatic arch, posterior ramus border, lateral border of the zygomaticus muscle, and anterior parotid gland border. Nerves were fixed, sectioned, and stained with SMI-31 antineurofilament stain for digital axonal analysis. Results: All specimens had one or more intraparotid zygomatic branches with over 900 axons, and 96 percent had an extraparotid branch with over 900 axons. The likelihood that a zygomatic branch would have over 900 axons at its last intraparotid point (mean, 6 mm posterior to the parotid border) was 92 percent (range, 67 to 100 percent) in contrast to 61 percent (range, 25 to 100 percent) when sampled at the first extraparotid point (mean, 14 mm anterior to the parotid border). Nerve cross-sectional area was positively correlated to its axonal count (R° = 78 percent; p < 0.0001), with nerve diameter over 0.6 mm predicting over 900 axons. Age did not correlate with axonal counts. Conclusions: Branches with adequate axonal load were found in all specimens. The likelihood of adequate branch selection improved from 61 percent to 92 percent with short retrograde intraparotid dissection. Nerve diameter correlated with axonal load.

UR - http://www.scopus.com/inward/record.url?scp=84987899485&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84987899485&partnerID=8YFLogxK

U2 - 10.1097/PRS.0000000000002897

DO - 10.1097/PRS.0000000000002897

M3 - Article

VL - 139

SP - 177

EP - 183

JO - Plastic and Reconstructive Surgery

JF - Plastic and Reconstructive Surgery

SN - 0032-1052

IS - 1

ER -