1) The document discusses the surgical anatomy of the salivary glands, with a focus on the parotid gland. It covers the embryology, anatomy, structures, blood supply and nerve supply of the parotid gland as well as different surgical approaches. 2) Retrograde dissection of the facial nerve during parotidectomy may provide advantages over antegrade dissection by reducing operating time and blood loss while preserving more normal parotid tissue. 3) Landmarks for identifying branches of the facial nerve during retrograde parotidectomy include the marginal branch relative to the mandible, the buccal branch relative to the zygomatic arch, and the temporal branch at the zygomatic

1. Surgical Anatomy of
Salivary Glands

2. CONTENTS
INTRODUCTION
EMBRYOLOGY
ANATOMY
FUNCTIONS OF SALIVA
CLASSIFICATION
SALIVARY GLAND DISORDERS

3. Introduction
The salivary glands are the exocrine glands, glands with ducts,
that produce saliva and pour their secretion in the oral cavity
.They are classified as:
1) Major (Paired) -Parotid
Submandibular Sublingual
2) Minor -Those in the Tongue, Palatine Tonsil, Palate
Lips & Cheek

4. Embryology
The parotid anlagen are the first to develop, followed by the
submandibular gland, and finally the sublingual gland.
Parenchymal tissue (secretory) of the glands arises from the
proliferation of oral epithelium.
The stroma (capsule and septae) of the glands originates from
mesenchyme that may be mesodermal or neural crest in origin.

5. STAGES OF DEVELOPMENT
BUD STAGE CORD STAGE TERMINAL BULB
LOBULE STAGE DUCT CANALISATION CYTODIFFERENTIATION

6.  Although the parotid anlagen are the first to develop, they become encapsulated after
the Submandibular gland(SMG) and Sublingual gland(SLG).
 This delayed encapsulation is critical because after the encapsulation of the SMG and
SLG but before encapsulation of the parotid, the lymphatic system develops.
 Therefore, there are intraglandular lymph nodes and lymphatic channels entrapped
within the parotid gland (PG).
 PG is also unique because its epithelial buds grow, branch and extend around
the divisions of the facial nerve.

7. PAROTID GLAND
• Largest major Salivary gland
• Average Wt - 25gm
• Irregular lobulated mass lying mainly below the external
acoustic meatus between mandible and sternomastoid.
• On the surface of the masseter, small detached part lies b/w
zygomatic arch and parotid duct- accessory parotid gland or
‘socia parotidis’

8. PAROTID CAPSULE :

9. External Features
-It resembles an inverted 3 sided pyramid having four surfaces –
• Superior(Base of the Pyramid)
• Superficial
• Anteromedial
• Posteromedial
-Separated by three borders :-
• Anterior
• Posterior
• Medial

10. Relations-
• Superior Surface –
• Concave
• Related to :
1) Cartilaginous part of external acoustic meatus
2) Post. Aspect of temperomandibular joint
3) Auriculotemporal Nerve
4) Sup. Temporal vessels

11. SUPERFICIAL SURFACE

12. ANTEROMEDIAL SURFACE

13. POSTEROMEDIAL SURFACE

14. BORDERS
• Anterior border
• Separates superficial surface from anteromedial surface
• Structures which emerge at this border
-Parotid Duct
-Terminal Branches of facial nerve
-Transverse facial vessels
Posterior border
• Separates superficial surface from posteromedial surface
• Overlaps sternocleidomastoid muscule
Medial Border-
• Separates anteromedial surface from posteromedial surface
• Related to lateral wall of pharynx

15. STRUCTURES WITHIN THE
PAROTID GLAND

16. ARTERIES
 It is doubtful whether ligation is of much value if
only a superfacial parotidectomy is to be performed,
since the anastomotic flow through the superficial
temporal and internal maxillary arteries is so free;
and in any case it is venous rather than arterial
bleeding which is the main problem in conservative
parotidectomy.
 The superficial temporal artery is, however, the
landmark for the auriculotemporal nerve, which lies
immediately behind the artery in front of the tragus
of the ear.

17. VEINS

18. NERVES

19. A suggested Surgico-anatomical Subdivision of the Parotid Gland-
The faciovenous plane divides the gland into two parts, one superficial to this plane and
the other deep which may be termed the superfacial parotid and the subfacial parotid.
The parts of the gland lying cranial and caudal to the facial nerve may be termed the
suprafacial (glenoid) and the infrafacial (cervical) extensions, these two extensions being
split into two when the gland is divided into its main super- and subfacial divisions. A
practical advantage of using this classification is that by it the surgeon can indicate
accurately, in describing partial parotidectomies, what parts of the parotid he has
removed and what parts he has left, a distinction that is usually not clear in most
descriptions of these operations at present.

20. FACIOVENOUS PLANE

22. Intraparotid anatomical relationship of Facial nerve with RMV and ECA:
A study was done by M. R. Laing and W. S. McKerrow in 1988 and was published as
“Intraoperative anatomy of facial nerve and retromandibular vein”.

24. Purpose: An accurate understanding of the anatomy, identification and preservation of facial nerve is critical in
performing successful functional parotidectomies. The current literature is replete with inconsistencies of various
landmarks when used alone for identification of facial nerve trunk (FNT). The purpose of the paper is to
introduce a new anatomical triangle, Borle's triangle (BT) for safer and reliable operative identification of FNT
during parotodectomies.
Results: Introperatively, BT helped reliably identify the FNT and its branches successfully in all the cases. The
mean distance of FNT from angle b was found to be 12.18 ± 1.7 mm. Transient neurological deficits with one or
more branches were seen in four cases, one case had transient deficit with all the five peripheral branches.
All of them spontaneously resolved completely by the end of three months post operatively.
Conclusions: When used in isolation, substantial variations exist in distances measured from anatomic landmarks
to the main FNT in the literature. The BT utilizes three commonly used anatomical landmarks. It predictably
helps in proper anatomic orientation, identification and preservation of FNT and branches with ease in parotidectomies.

25. Parotid Duct
• ductus parotideus; Stensen’s duct
• 5 cm in length and 3mm wide
• Runs anteriorly and downwards on the masseter b/w the upper
and lower buccal branches of facial.
At the anterior border of masseter it pierces
• Buccal pad of fat
• Buccopharyngeal fascia
• Buccinator Muscle
• It opens into the vestibule of mouth
opposite to the 2nd upper molar

26. Surface anatomy of Parotid Duct
• Corresponds to middle third of a line drawn from lower border of tragus to a
point midway b/w nasal ala and upperlabial margin.

27. The purpose of this study is to examine the surgical anatomy of the
parotid duct with special emphasis placed on the major tributaries
forming the parotid duct and the relationship of the facial nerve to the
duct.
In all cases, the deep lobe of the parotid enveloped the parotid duct; only
small ductules connected the superficial lobe with the duct.
The facial nerve and its branches were always observed lateral to the
parotid duct. Because one dissects lateral to the facial nerve during a
superficial parotidectomy, generally the parotid duct remains intact and
potential complications such as facial paralysis, sialoceles, and
fistulizations are thereby minimized.

29. NERVE SUPPLY
•Parasymapthetic N
• Secretomotor via
auriculotemporal N
•Symapathetic N
• Vasomotor
• Delivered from plexus around
the middle meningeal artery
•Sensory N
• Reach through the Great
auricular and auriculotemporal N

30. Blood supply
• Arterial-
Branch of External Carotid artery
• Venous-
Into the External Juglar vein and
Internal jugular vein
• Lymphatic drainage-
Upper deep Cervical nodes via Parotid nodes

31. INCISIONS
1.MODIFIED BLAIR INCISION
2.LAZY S INCISION
3.FACELIFT(RHYTIDECTOMY) INCISION
4.U-SHAPED OR MICROPAROTIDECTOMY INCISION
5.RETROAURICULAR HAIRLINE INCISION

32. MODIFIED BLAIR INCISION
In 1912, Blair was the first to use the incision that is
employed today with a modification by Bailey in
1941.The modified Blair incision is the workhorse
incision for most parotid surgery. It combines the
inverted L-shaped (hockey stick) pre-auricular
incision of Blair with a cervical limb extending into
the neck.
Advantage- Exposure of the entire periphery of the
gland and excellent access to the facial nerve. It
raises a robust flap that resists flap necrosis.
The incision further allows extension into a neck
dissection incision and cervicofacial flap elevation. It
is cosmetically acceptable and if placed in a natural
skin crease, it is difficult to discern.

33. LAZY S INCISION
It begins at the level of the tragus along a
preauricular crease winding around the lobule in a
more obtuse manner to curve anteriorly 2
inches along the anterior border of the
sternocleidomastoid muscle along an upper
cervical crease.
A benefit of this incision is that the retroauricular
portion of the incision is shorter and minimizes the
chance of flap loss and scarring in that location.

34. FACELIFT (RHYTIDECTOMY) INCISION
It originates at the superior root of the helix and
lies just inside the anterior edge of the tragus,
curving superiorly around the lobule towards the
mastoid, preserving the sulcus between lobule
and the cheek, continuing in a postauricular
crease to the occipital hairline without traversing
the hairless mastoid region and then descends
inferiorly approximately 6cm to the edge of the
hairline.
This incision is ideal for benign, posteriorly located
tumors.

35. U-SHAPED INCISION
This incision consists of pre- and post-
auricular incisions joined to curve
around the lobule. It begins in a
preauricular crease at the superior
root of the helix descending in the
crease to curve below the lobule,
extending superiorly around the
lobule towards the mastoid in a
postauricular crease.
This incision is ideal for small, benign
tumors within the superficial lobe of
the parotid gland, especially when
located in the tail of the gland or close
to the tragus.

36. RETROAURICULAR HAIRLINE INCISION
The incision begins at the inferior end of the
postauricular sulcus, extending superiorly to the
upper one-third point of the sulcus and angles
downward to continue 0.5 to 1 cm along the
inside of the hairline. Dissection proceeds anteriorly
to the mastoid fascia to the base of the conchal
bowl. This incision is ideal for posterior, superficial,
benign parotid tumors.

38. Objective. To systematically review the literature on the
modified facelift incision for parotidectomy and to
identify the scope and safety of this approach, along with
cosmetic outcomes. Where available, a direct
comparison was made with Blair’s incision (BI).
Conclusion. The facelift approach is a cosmetically
superior approach to parotid tumors as proven by
objective data. Most publications in the literature
pertaining to the modified facelift incision for
parotidectomy have been in the past decade, lending
credence to its rising popularity.

39. INTRODUCTION: Traditionally, the cervicomastoidfacial
(CMF) incision is used to excise benign tumours of the
parotid gland.The modified facelift (MF) incision allows
an alternative approach which leaves no visible neck
scar. The objective of this study was to establish the
frequency of each surgical approach used and identify
any difference in complication and patient satisfaction
between the two incisions for benign conditions of the
parotid gland.
CONCLUSIONS :Immediate and late complications for
CMF and MF approaches for benign disease
parotidectomy were comparable, but scar satisfaction
following MF incision was not greater than CMF
incisions.

40. The tragus is a small curved flap of tissue comprised of cartilage and is located
below the crus of the helix and anterior to the concha. It projects posteriorly
over the meatal orifice. The anterior part of the tragus points anterior, inferior,
and deep to the superficial surface of the preauricular area. Its anterior
end takes on a bluntly pointed shape on its medial aspect and is named the
“pointer”.

41. Types of Parotidectomy
• Partial parotidectomy: Resection of parotid pathology with a margin
of nor-mal parotid tissue. This is the standard operation for benign
pathology and favourable malignancies .
• Superficial parotidectomy: Resection of the entire superficial lobe of
parotid and is generally used for metastases to parotid lymph nodes
e.g. from skin cancers, and for high grade malignant parotid tumours.
• Total parotidectomy: This involves resection of the entire parotid
gland, usually with preservation of the facial nerve.
• Extracapsular parotidectomy: The tumour is carefully dissected
along its capsule without identifying the facial nerve, and relying on
facial nerve monitoring to avoid injury to branches of the nerve .

42. Parotidectomy with facial nerve dissection

50. LATERAL PHARYNGEAL SPACE
Diagrams of transverse section at the level of the
first cervical vertebra to illustrate the anatomy of
the ‘lateral pharyngeal space ‘. It will be seen that
apart from the superficial entrance to the space,
which is plugged by the parotid gland, the space
is otherwise a closed one, and in particular does
not communicate with the main retropharyngeal
space.

51. Parotid dissection for deep lobe tumours

53. Facial Nerve Repair

54. Aim: Classically, parotidectomy is performed by the antegrade facial nerve dissection technique. However,
a significant amount of normal parotid parenchyma is mobilized and killed needlessly, without enhancing the
oncological outcome, as most tumours do not reside in the proximity of the facial nerve trunk. We investigate
whether retrograde facial nerve dissection (the facial nerve branches were identified and dissected proximally)
is a safe or better alternative.
(i) the marginal branch is superficial to the anterior facial vessel 1–2 cm within the lower border of mandible;
(ii) the buccal branch is 1 cm below and parallel to the zygomatic arch just above the parotid duct;
(iii) Temporal branch crosses the junction of the anterior, onethird, and posterior, two-thirds of the zygomatic arch.
RESULTS- The mean operation time was shorter in the retrograde group: 144 min versus 176.2 min (P = 0.002). The
postoperative stay was also shorter for the retrograde group: 3.3 days versus 4.1 days (P = 0.037). There was no tumour
relapse in either group. More great auricular nerves were divided in the antegrade group: 59 per cent versus 10.3 per cent (P
= 0.009). A consistent trend of a lower rate of transient facial palsy, pinna numbness, sialocele/salivary fistula and Frey’s
syndrome was seen in the retrograde group, although they were statistically insignificant.

55. Purpose: Retrograde parotidectomy is employed in situations where tumors or scar tissue obscure the
facial nerve trunk, making anterograde parotidectomy hazardous. Hence, the reliability of anatomical
landmarks in retrograde parotidectomy is of equal practical importance.
Conclusion: The findings indicate that all three landmarks are useful for surgeons to locate the facial
nerve branches during retrograde parotidectomy. Since all three landmarks were consistent indicators
for the corresponding facial nerve branches, the surgeon has more than one option should one landmark
be obscured by tumors.

56. OBJECTIVE: The primary aim of this meta-analysis was to test the null hypothesis of no difference in facial
nerve dysfunction in studies that compared classical antegrade facial nerve dissection (AFND) versus
retrograde facial nerve dissection (RFND) during benign parotid surgery.
RESULT: There was reduction in the operative time (19.30 min), amount of blood loss (25.08 ml) and amount of healthy
salivary tissues removed (12.20 mm) in RFND compared with AFND.
CONCLUSION: According to the results of the current review there is no evidence demonstrating a significant
advantage of one approach over another, therefore, well-designed standardized RCTs are required.

57. Removal of deep-lobe parotid tumours from the parapharyngeal space
is often difficult because of limited surgical access and the critical
vascular and neurologic structures nearby. Mandibulotomy, when
necessary, is useful for improving wider visibility and control of the
vascular bundle and facial nerve, but may cause damage to the inferior
dental and lingual nerves. The double mandibular osteotomy with
coronoidectomy gives excellent access and avoids damage to these
nerves.

58. OBJECTIVE: Despite its proven safety and its relevance regarding the cosmetic outcome, the
SMAS-lifting technique is not a routine procedure for many surgeons. To compare the classical
(subcutaneous flap and neck incision) with the SMAS-lifting techniques for parotidectomies
from the patient’s perspective.
CONCLUSION: The SMAS-lifting technique might possibly appear to offer a new standard
procedure for parotidectomy, except for malignant tumours or in obese patients.

59. why remove the deep lobe?
If it is involved by cancer or at high risk of malignancy, either primary or metastatic. The deep
portion should not be viewed as unique or different from the superficial portion, only that it is
smaller with fewer nodes present.
When should it be removed?
In all cases of direct extension of a primary cancer to the deep lobe or with a primary deep lobe
parotid cancer.
How does one do a deep lobe removal?
The performance of an en bloc deep lobe removal is an operation that can best remove
potential metastasis to the deep parotid nodes. This surgical procedure requires knowledge of
embryology, anatomy, and parotid lymphatic connections and tumor behavior. The technique
of a complete deep lobe removal with facial nerve preservation is a well-described procedure.

60. Traditionally, deep -lobe tumors have been managed by a formal superficial parotidectomy and identification and
preservation of the facial nerve followed by removal of the deep lobe that contains the tumor Superficial
parotidectomy is associated in most cases with periauricular depression.Secondary to a loss of volume, leading to
variable aesthetic Deformities. Therefore, we decided to preserve the superficial lobe of the gland for deep-lobe
Tumors.
There were no cases of postparotidectomy depression, and both patients and surgeons were satisfied with the
cosmetic appearance.

61. Facial nerve dysfunction
In comparing the different types of incisions in patients who underwent superficial
parotidectomy, we found a greater rate of temporary facial nerve dysfunction with the
modified Blair incision 64% (9 of 14 patients) compared with the facelift incision 28%
(5 of 18 patients). Again, all patients that had superficial parotidectomy for benign
disease had complete recovery of their facial nerve function within 6 months after
surgery.

62. Seroma and sialocele
Fluid collections at the surgical site after parotidectomy are often described as seromas or
sialoceles . The infections did not have an impact on facial nerve function, but did
appear to cause partial loss of the graft with resultant soft tissue deficit.
Because of these infections, we have increased our vigilance for sterility. We administer
intraoperative antibiotics and postoperative antibiotics, irrigate the wound with antibiotic
irrigation (clindamycin, 2400 mg/1 L saline) and change gloves before handling the
allograft implant. Recently, we have been placing a scopolamine patch on the
patients in an effort to decrease salivary flow during the first week postoperatively.

63. Frey’s syndrome

64. The perioperative techniques adopted to avoid complications:
1. Knowledge of anatomy of this area is of utmost importance while performing parotidectomy
surgery.
2. Informed consent:The probable complications should also be explained to the patient and
concerned relatives.
3. Anesthesia:Paralytics are used while induction thereby their use is avoided. This helps in
intraoperative monitoring of facial nerve.
4. Incision and flap raising: a modified Blair incision is used. An adequate cuff of tissue should be
present around the ear lobule; this will prevent pixie-ear deformity. The tapering of
postauricular skin flap should be avoided; else skin flap necrosis occurs post operatively. The
advantage of sub-SMAS flap is that it reduces the incidence of postoperative Frey’s syndrome
and development of divot defect after gland removal.

65. 5.Identification of facial nerve and dissection of gland: identification of facial nerve is of
utmost importance in parotid surgery.
6. Parotid duct: whenever feasible we try to preserve parotid duct during superficial
parotidectomy. In our experience it reduces the chances of sialocele as the saliva from
parotid remnant is drained out through this duct.
7. A suction drain and pressure dressing is kept for 48 h to prevent collection and
antibiotic coverage is given for 5 days.

66. OBJECTIVE:The aim of the present study was to compare the outcomes of superficial
parotidectomy (SP) and partial superficial parotidectomy (PSP) in treating benign parotid
tumors.
CONCLUSION:Those with PSP demonstrated improved scores in the domains of appearance,
facial contours, facial nerve function and Frey's syndrome. Compared with SP, PSP not only
decreased the incidence of Frey's syndrome and transient facial nerve weakness, but also
improved quality of life outcomes and guaranteed a low recurrence rate.

67. OBJECTIVE: The type and extent of surgery for benign parotid tumors is a subject of debate. The
investigators aimed to measure and compare hospital stay, operative time, and complications rates
associated with superficial parotidectomy (SP) and partial superficial parotidectomy (PSP).
CONCLUSION:In the SP group, the PSP group had shorter operative and hospital stay durations and fewer
postoperative complications with a comparable recurrence rate. Therefore, PSP should be considered in
suitable cases.
We conclude that the less invasive procedure should be considered in patients with mobile tumors less than
3 cm that are located in the tail or superficial lobe of the parotid gland. However, our mean follow-up period
for patients who underwent PSP was 5 years; thus, the long-term effects and benefits of this technique
remain largely unknown. Studies with longer follow-up periods are necessary to fully understand the long-
term outcomes of PSP.

68. Prevention:
 The most important way to prevent Frey syndrome is to minimize the parotid
wound bed while adequately removing the pathology. Therefore, partial superficial
parotidectomy, if possible, is recommended to minimize the risk of Frey syndrome.
 A significant lower incidence of Frey syndrome after parotidectomy if a thick skin flap is
made using a scissor dissection.
 Radiotherapy significantly reduces the incidence of gustatory sweating.
 Interposition of barriers to prevent aberrant reinnervation of parasymphatetic fibers have
been described.
 Kornblut et al were the first to report on the use of a superiorly-based sternocleidomastoid
muscle flap to prevent Frey syndrome.

69. TREATMENT:
The most commonly used method consists of reelevation of the cheek skin flap and interposition of various tissue
barriers like dermal graft and temporoparietal fascia between the cheek skin and the parotid gland.
Reelevation of the skin flap and excision of the involved skin followed by skin grafting have also been used.
Tympanic neurectomy is described as treatment for Frey syndrome.
Topically anticholinergic medications are effective in treating Frey syndrome for several days. Scopolamine is a
tertiary amine preparation, which penetrates skin easily and blocks cholinergic transmission.
Glycopyrrolate is a quaternary ammonium compound, which penetrates skin slowly and blocks cholinergic
transmission.
0.1cc intradermal injection of prilocarpine.
Favorable results have been reported on the treatment of Frey syndrome by intracutaneous injections of
botulinum toxin A .

71. Management of parotid fistula is not only challenging for a surgeon but also controversial, too.
Management includes both non-surgical and surgical options. Non-surgical options include pressure dressing,
anti-sialogogues, radiotherapy, botulinum toxin A injection.
Surgical techniques are demanding but may lead to another un-acceptable complication, like facial nerve palsy.
Tympanic neurectomy appears to be an effective method of suppression of parotid secretion but, on some
occasions, proves transient.
Fibrin glue has been used recently but it is rendered inactive by the saliva so the results are not as much
promising as previously thought of.
Pressure dressing is thought to promote pressure necrosis/atrophy of the gland. The sustained rise in the ductal
pressure causes capillary/venous congestion/ compression, ultimately leading to the decreased secretion.

73. MANAGEMENT:
Primary Nerve Repair.
Primary neurorrhaphy provides the best chance for nerve function recovery, as
demonstrated in histologic and electrophysiologic studies.
Nerve Grafting.
If a nerve gap exists despite nerve ending mobilization, nerve grafting is indicated.
Nerve Transfers.
Acute nerve transfers in the trauma setting are uncommon. However, they may be used
concomitantly with intratemporal nerve grafting or solely when grafting is not possible.

75. House-Brackmann Grading
System

76. Facial Nerve Testing
• Used to assess the degree of electrical dysfunction
• Can pinpoint the site of injury
• Helps determine treatment
• Can predict recovery of function – partial paralysis is
a much better prognosis than total paralysis
• Divided into two categories
– Topographic tests
• Tests function of specific facial nerve branches
• Do not predict potential recovery of function
• Rarely utilized today
– Electrodiagnostic tests
• Utilize electrical stimulation to assess function
• Most commonly used today

77. Nerve Excitability Test (NET)
• Compares amount of current required to illicit
minimal muscle contraction - normal side vs.
paralyzed side
• How it is performed
• A stimulating electrode is applied over the stylomastoid foramen
• DC current is applied percutaneously
• Face monitored for movement
• The electrode is then repositioned to the opposite side,
and the test is performed again
• A difference of 3.5 mA or greater between the two
sides is considered significant
• Drawback - relies on a visual end point
(subjective)

78. Maximal Stimulation Test (MST)
• Similar to the NET, except it utilizes
maximal stimulation rather than minimal
• The paralyzed side is compared to the
contralateral side
• Comparison rated as equal, slightly
decreased, markedly decreased, or absent
– Equal or slightly decreased response = favorable for complete recovery
– Markedly decreased or absent response = advanced degeneration with a poor prognosis
• Drawback - Subjective

79. Electroneurography (ENoG)
Thought to be the most accurate of the electrodiagnostic tests
How it works:
Bipolar electrodes deliver an impulse to the FN at the
stylomastoid foramen
Summation potential is recorded by another device
The peak to peak amplitude is proportional to number of intact
axons
The two sides are compared as a percentage of response
90% degeneration – surgical decompression should be performed
Less than 90% degeneration within 3 weeks predicts 80 - 100%
spontaneous recovery
Disadvantages: discomfort, cost, and test-retest variability

80. Electromyography
• Determines the activity of the muscle itself
• How it works
– Needle electrode is inserted into the muscle, and
recordings are made during rest and voluntary
contraction
• Normal = biphasic or triphasic potentials
• 10-21 days post injury - fibrillations
• 6-12 weeks prior to clinical return of facial
function – polyphasic potentials are recordable
– Considered the earliest evidence of nerve recovery
• Does not require comparison with normal side

81. Ideally, facial nerve monitoring during parotid surgery would allow
(1) early nerve identification,
(2) warning of the surgeon of unexpected facial nerve stimulation,
(3) mapping of the course of the nerve,
(4) reduction of mechanical nerve trauma,
(5) evaluation and prognostication of function at the conclusion of the procedure.
Recent prospective trials have demonstrated that electrophysiological facial nerve monitoring can reduce
the risk of early postoperative facial nerve dysfunction in primary parotid surgery, but not in revision
surgery. The effect is more pronounced in total than in superficial parotidectomy.

82. SUBMANDIBULAR AND SUBLINGUAL
GLANDS

83. SUBMANDIBULAR SALIVARY GLANDS
• Irregular in shape
• Weigh about 15 grams and contribute
some 60–67% of unstimulated saliva
secretion.
• Large superficial and small deeper part continous with each
other around the posterior border of mylohyoid.

84. Superficial Part
• Situated in the digastric triangle
• Wedged b/w body of mandible and mylohyoid
• 3 surfaces
• Inferior, Medial, Lateral

85. Capsule
• Derived from deep cervical fascia
• Superficial Layer is attached to base of mandible
• Deep layer attached to mylohyoid line of mandible

86. Relations
• Inferior-
• covered by--

87. • Medial surface
• Anterior part is related to mylohyoid muscle, nerve and vessels.
• Middle part - Hyoglossus, styloglossus, lingual nerve,
submandibular ganglion, hypoglossal nerve and deep lingual vein.
• Posterior Part - Styloglossus, stylohyoid ligament,9th nerve and
wall of pharynx

88. LATERAL SURFACE
The submandibular fossa on the mandible.
The facial artery.
Insertion of the medial pterygoid.

89. • Deep part
• Small in size
• Lies deep to mylohyoid and superficial to
hyoglossus and styloglossus.
• Posteriorly continuous with superficial part
around the posterior border of mylohyoid.

90. Submandibular Duct
• Whartons duct
• 5 cm long
• Emerges at the anterior end of deep part of the gland.
• Runs forwards on hyoglossus b/w lingual and hypoglossal
nerve.
• At the ant. Border of hyoglossus it is crossed by lingual
nerve.
• Opens in the floor of mouth at the side of frenulum of
tongue.

91. Blood supply and lymphatics
• Arteries
• Branches of facial and lingualarteries
• Veins
• Drains to common facial vein or lingual vein.
• Lymphatics
• Deep Cervical Nodes via submandibular nodes

92. NERVE SUPPLY
• Parasymapthetic fibers from chorda tympani
• Sensory fibers from lingual branch of mandibular nerve
• Sympathetic fibers from plexus on facial A

94. In a majority of the dissections (52%), the marginal mandibular branch of the
facial nerve was found running along the angle and inferior border of the
mandible. It was observed below the inferior border of the mandible in 32% of
the cases. When below the angle and body of the mandible, its maximum
distance was found to be 1.6 and 1.4 cm, respectively. Therefore, in order to
avoid damage to the marginal mandibular branch of the facial nerve,
the submandibular incision should be planned 1.6 cm or more below the lower
border and angle of the mandible. The marginal mandibular branch of the
facial nerve was found superficial to the facial artery and (anterior) facial vein
in all the cases (100%). Thus, the facial artery can be used as an important
landmark in locating the marginal mandibular nerve during surgical
procedures.

95. Surgical Technique:
Excision of the Submandibular Gland

103. The transcervical procedure used for treating sialolithiasis in the
submandibular gland has been generally accepted by head and neck
surgeons. However, several clinical problems after surgery through the
transcervical approach have been
described. We introduce a new surgical approach for excision of the
submandibular gland indicated in the chronically inflamed salivary gland
with or without calculus and benign mixed tumor of the submandibular
gland.
This approach can be extended to the excision
of the chronically inflamed submandibular gland or
benign tumor as an alternative to the transcervical
approach. The major advantages of this approach are
the avoidance of an external scar and of injury to the
mandibular branch of the facial nerve or the hypoglossal nerve.

104. Exposure keratopathy can be avoided
initially by instituting supportive measures, such as the use of
lubricating eyedrops, and ointment. Botulinum toxin can be
injected into Muller muscle and the levator palpebrae superioris
to counteract lagophthalmos in a temporary fashion.
In a similar approach, hyaluronic acid may also be injected
into the upper lid in a plane superficial to the levator
aponeurosis and tarsal plate to promote eye closure.
The implantation of a static weight to load the upper lid and
achieve eye closure has been successfully performed, since the
1960s.Goldweight implantation in conjunction with
lateral tarsorrhaphy has been shown to generate complete eye
closure in 83% of patients after one procedure.

105. Disability in the lower face resulting from facial
paralysis consists mainly of oral incompetence,
manifesting as ptyalism, and difficulty with
eating and drinking, poor articulation,
and loss of smile and expressivity. Static slings,
suspended from the zygomatic arch or deep
temporal fascia to support the oral
commissure and upper lip, lead to the
elevation of these structures and the
recreation of the nasolabial fold.An inferior
displacement of the affected oral commissure,
oral incompetence, upper and lower lip
asymmetry are commonly seen with
facial paralysis. Upper lip philtral ridge is also
commonly displaced to the unaffected side.
Static suspension of lower lip can be used to
address gross lip asymmetry, drooling and oral
incompetence. Fascia lata, Gore-Tex and
Alloderm can be used to suspend in a
superoposterior vector.

106. Nerve Transposition
When transfer of the contralateral facial nerve is not an
option, ipsilateral transfer of hypoglossal, masseteric,
spinal accessory, ansa cervicalis, recurrent laryngeal, and
phrenic motor nerve fibers is possible. Hypoglossal nerve
transfer is the most commonly described, followed by
the masseter motor nerve.While the hypoglossal nerve
transfer historically entails its complete transection,
modification of this technique with transfer of 50% of
the hypoglossal nerve fibers provides similar outcomes,
but with less tongue weakness and swallowing
dysfunctionThe masseter nerve represents a good
candidate for nerve transfer due to its good size match,
length, easy dissection, and minimal impact on
masticatory function when dissected intramuscularly to
a distal segment. Transfer of the masseter nerve has
been shown to result in a more rapid return of facial
function compared with hypoglossal transfer with nerve
grafting.

107. Regional Muscle Transfer
Dynamic muscle transfer can be performed by
transposing regional muscle or by free muscle
flap transfer. The mainstay of regional muscle
transposition is the temporalis muscle
transfer, originally described for lower facial
reanimation, involving rotation of the
temporalis over the zygomatic arch and
anchoring it to the oral commissure.

108. Advantages:
1. Reduction in intraoperative blood loss,
2. Reduction in operating time (avoiding ligatures or electric
coagulation for hemostasis),
3. Reduced drainage,
4. Lesser seroma formation,
5. Decreased postoperative pain (minimum eschar formation
and tissue dessication)
6. Better wound healing when compared with the standard
technique using surgical diathermy .

110. In conclusion, this approach might be extended to the
excision of the benign submandibular tumors by the result
of a long-term follow-up, even though one patient showed
recurrence of the tumor at the early stage of this approach.
This approach may be difficult due to narrow surgical field,
but is especially a benefit to young women because of the
avoidance of an external scar and of nerve injury.

111. OBJECTIVE:The purpose of this study is to evaluate the benefits of the intraoral approach for removal of the
submandibular gland (SMG) by comparing it with the usual method of the transcervical approach.
RESULT:The mean operation time of the IOA group was significantly longer than that of the TCA group, but
decreased gradually with surgical experience. The mean hospital stay of the IOA group was significantly shorter
than that of the TCA group.
CONCLUSION: the SMG can be removed safely and effectively by IOA with the avoidance of an external scar
and of injury to the marginal mandibular nerve. We suggest that the IOA be substituted for the TCA as the
primary procedure for removal of the SMG in suitably selected patients.

112. Sialendoscopy
It is a minimally invasive surgery that can successfully relieve blockages not amenable to intraoral approaches also
permits both diagnostic assessment and definitive treatment in the same operative session.
Indications:
1. Diagnostic e.g. recurrent episodes of swelling of major
salivary gland without an obvious cause.
2. Treatment (interventional sialendoscopy) of submandibular
and parotid sialadenitis, including sialolithiasis
3. Exploration of the ductal system following removal of calculi
from the anterior or middle parts of the submandibular and
parotid ducts.
4. Strictures or kinks of the salivary ductal system
5. Paediatric inflammatory and obstructive pathology
Contraindications:
Acute sialadenitis is a contraindication as the risks of
ductal injury and perforation are increased due to the
inflammation and inability to visualize .

113. Complications of sialendoscopy:
The severity of complications is generally quite modest and includes ductal perforation,
basket entrapment, ductal avulsion, postoperative infection and ductal strictures, swelling in
the floor of mouth with potential airway compromise and recurrence of symptoms . Risks
associated with transoral submandibular approaches include lingual nerve injury and bleeding.

114. In two cadavers higher origin of
facial artery was observed on left
side (3.33 %). Facial artery was
found originating from the external
carotid artery just below the origin
of maxillary artery within the
parotid gland. On further tracing,
artery turns forwards and medially
along the lower border of the
mandible. It hooks the lower border
of the mandible and turns upwards
at the antero-inferior angle of the
masseter.

115. Facial artery has been considered to be the most important
vascular pedicle in facial rejuvenation procedures and submandibular
gland (SMG) resection.The reported variations of the FA include its
intraparotid origin; a common linguofacial trunk; duplex FA; termination
as submental artery, labial artery, or lateral nasal artery;
absence.
The FA was seen jutting from ECA superficial to the intermediate
tendon of digastric in the deeper part of submandibular triangle. The
origin of FA was 32 mm distal to the common carotid artery
bifurcation. It made a distinct transverse S-shaped loop beneath the
SMG in its cervical part. The hypoglossal nerve traversed beneath
this loop of FA before reaching its target.
Further in its course, FA did not lodge on the posterior end of SMG,
instead it was seen to pierce the salivary gland through and through
(Fig. 1, §) from the deeper surface before emerging on the superficial
surface. At the exit, it immediately gave the submental branch
before entering the face, which coursed along the lower border of
the body of the mandible.

116. Facial artery is usually the main artery supplying the face. It gives three named branches on the face, the inferior labial, the
superior labial and the lateral nasal and continues as the angular artery. Face is also supplied by the transverse facial artery and
the arteries accompanying the cutaneous nerves.
They observed that the facial artery terminated as Inferior labial
artery as end artery (without anastomoses). The other branches for
the face like Superior labial, lateral nasal and angular arteries are
arises from the Transverse facial artery.

117. On the left side,
the course of the facial artery was normal in both neck
and face. However, there was no inferior labial artery
and remaining branches i.e., superior labial, lateral nasal
and angular arteries were normal but more prominent
The right facial artery was seen to
arise from external carotid artery above the
greater cornu of the hyoid bone.

118. The objective of this study was to report a variation of the facial artery and to analyze
it in relation to the literature state of the art.
They reported, in the right hemiface, a supernumerary branch of the facial artery
emerged between the origins of submental and inferior lip arteries, close to the
bottom edge of the mandible body, going towards the infra-orbital region.

119. Sublingual Salivary Glands
• smallest of the three glands
• weighs nearly 3-4 gm
• Lies beneath the oral mucosa in contact with the sublingual fossa on lingual aspect
of mandible.

120. Relations
• Above
• Mucosa of oral floor, raised as sublingualfold
• Below
• Mylohyoid In front
• Behind
• Deep part of Submandibulargland

121. • Lateral
• Mandible above the anterior part
of mylohyoid line
• Medial
• Genioglossus and separated from it
by lingual nerve and submandibular
duct

122. SUBLINGUAL DUCT
• Ducts of Rivinus
• 8-20 ducts
• Most of them open directly into the floor
of mouth
• Few of them join the submandibular duct

123. •Blood supply
• Arterial from sublingual and submental
arteries
• Venous drainage corresponds to the
arteries
•Nerve Supply
• Similar to that of submandibular glands(
via lingual nerve , chorda tympani and
sympathetic fibers)

124. Applied aspects
• The structures at risk during dissection of the
gland are the submandibular duct and the
lingual nerve.
• The duct lies superficially in the floor of the
mouth medial to the sublingual fold, and is
crossed inferiorly by the nerve which then
enters the tongue
• The sublingual artery and vein also lie on the
medial aspect of the gland close to the
submandibular duct and lingual nerve.

125. Treatment consists of total removal of the sublingual gland and
evacuation of the contents through the intraoralapproach.The safe,
effective, and definitive treatment for all ranulas, that yields the
lowest recurrence rate and morbidity, is transoral excision of the
ipsilateral sublingual gland with evacuation of the ranula.A little
fluid from plunging and mixed ranulas remains just after excision,
but gradually regresses and disappears within two months of the
operation.