From: Marginal mandibular nerve — a wandering enigma and ways to tackle it
First author | Type of study/no. of cases/specimens | Landmark | Relation to lower border of mandible |
---|---|---|---|
Balagopal | Neck dissection in 202 patients | Point where facial artery crosses LBM | Mean distance of 1.73 mm from the LBM to where MMN crossed facial artery |
Batra | Embalmed cadavers, 50 facial hemi-halves | Inferior border and angle of mandible | Avg distance from the following: 1. LBM–1.2 cm 2. Angle of mandible—1.5 cm |
Al-Hayani | Post-mortem study in 50 subjects | LBM | Above LBM—28% Below LBM—44% Above and below LBM—28% Branches above LBM—deep to parotid fascia Branches below LBM—located intrafascially |
Liu | Cadaver dissection in 24 specimens | LBM | MMN courses within 13.4 mm above and 4.8 mm below in relation to LBM |
Kim | Cadaver dissection 85 facial halves | Go, LBM, anterior border of parotid gland | Distribution of MMN nerve within Quadrilateral formed by + 19.8 mm, − 8.1 mm,+ 30.0 mm, and − 15.3 mm from 2 sides of LBM Mean distance of 3.4 mm ± 6.0 mm from gonion to MMN at parotid anterior edge |
Karapinar | Cadaver dissection of 44 facial halves | LBM | Avg distance from LBM is 21.91 mm varying from 13.06 to 40.08 mm |
Hazani | 18 cadaveric facial halves | Masseteric tuberosity and mental midline | MMN concluded to lie 3 mm anterior to masseteric tuberosity |
S Toure | Cadaver dissection study on 54 cadavers | Inferior border and angle of mandible | Lowest MMN branch courses 17.5 mm LBM |
Woltmann | 45 hemifaces of 27 Brazillian cadavers | LBM | MMN courses between − 1.3 and + 1.2 cm from the LBM 57%—superior to mandibular margin 43%—below inferior mandibular margin |
Ziarah | 110 cadaveric cervico-facial halves | LBM | MMN found within 0.6cm above and 1.2 cm below LBM 47% above and 53% below the LBM till the nerve reaches facial vessels |
Potgieter | Embalmed cadaver dissection of 36 facial halves | Angle of mandible | Median distance from angle of mandible (point A) to the nerve was 2.3 mm inferior to point A |
Nason | 133 neck dissections | LBM | MMN nerve found 1.25 ± 0.7 cm below the mandible when the neck was extended 54%—MMN > 1 cm below LBM |
Baker | Clinical experience on parotidectomies | LBM | MMN lies 1–2 cm from LBM in almost 100% cases |
Al-Qahtani | 52 otolaryngeal patients | LBM and angle of mandible | Mean nerve position with respect to: Right angle of mandible, 2.7 mm above Right lowest point in LBM, 0.2 mm above Left angle of mandible, 3.4 mm above Left lowest point in LBM, 1.3 mm above Lowest point of MMN branch from right and left angle of mandible was 10 mm and 6 mm below, respectively. Lowest point of MMN branch from right and left lowest point in LBM was 10 mm below in both. Highest point of MMN branch from right and left angle of mandible was 20 mm and 13 mm above, respectively. Highest point of MMN branch from right and left lowest point in LBM was 10 mm above in both. |
Huu-Mu Yang | Cadaver dissection of 12 embalmed and 4 fresh cadavers | Go, facial artery, LBM | From Go to mentum, MMN is superior to LBM in 44.8% and inferior to LBM in 55.2%. MMN crossed LBM and reached the mandible at a mean distance of 33.1 ± 5.2 mm anterior to Go. MMN lies within 5 mm of Go in 82.8% cases. |
Khanfour | Cadaver dissection of 30 specimens | LBM | Relation of MMN and branches to LBM at a point midway between angle and symphysis menti of mandible: 80%—above at a mean distance of 1.3 ± 0.12 mm 10%—same level as LBM 10%—below at a mean distance of 1.6 ± 0.1 mm |