The para-pharyngeal space is an inverted pyramid-shaped area located between the muscles of mastication and muscles of deglutition. It has important structures passing through like the internal carotid artery and cranial nerves. Lesions in this space can be benign like pleomorphic adenomas or malignant like metastases. Imaging with CT or MRI is important for evaluating these lesions. The transcervical approach is most commonly used for surgery but transoral, transparotid, and infratemporal fossa approaches may also be used depending on the location and extent of the lesion. Complications can include nerve injuries, bleeding, and infection. New advances like transoral robotic surgery may help access some lesions with fewer complications.
2. INTRODUCTION
ā¢ understanding of the anatomy and
relationship of the various neck spaces
is valuable in diagnosing and treating
diseases of the neck
4. PARA-PHARYNGEAL SPACE
ā¢ Inverted pyramid with floor at
skull base, tip at hyoid, bounded
by the pharyngeal wall medially
and the mandible laterally
ā¢ Also known as-lateral pharyngeal
space, pharyngomaxillary space,
pterygomaxillary space,
pterygopharyngeal space.
5. BOUNDARIES OF PPS
The space between the muscles of mastication and
the muscles of deglutition.
Superior: base of skull.
Inferior: greater cornu of the hyoid bone.
ā¢ Medial: middle layer of the deep cervical
fascia covering
the superior pharyngeal constrictor
levator
ā¢ tensor veli palatini muscles
6. BOUNDARIES OF PPS
ā¢ lateral: superficial layer of the deep cervical
fascia extending between styloid
process and mandibular ramus,1
ā¢ anterior: pterygomandibular raphe and
superficial layer of the deep cervical
fascia covering the medial pterygoid muscle
7. CONTā¦.
posterior: an extension of tensor
veli palatini muscle fascia termed
the tensor-vascular-styloid fascia
; or an extension of the fascia of
the stylopharyngeus, styloglossus
, and levator veli palatini muscles.
11. PRESTYLOID LESIONS
Pleomorphic adenoma - medial extension
of a deep lobe parotid tumour
Salivary gland tumors
Lipoma
Neurogenic tumors like trigeminal
schwanomma
Abscess
Cystic hygroma
Second branchial cleft cyst
12. PRESENTING SYMPTOMS OF PRESTYLOID LESIONS
ā¢ Asymptomatic.
ā¢ Medial displacement of the lateral pharyngeal wall
and tonsil is a hallmark of a parapharyngeal space
infection
ā¢ . Trismus, drooling, dysphagia, and odynophagia are
also commonly observed.
ā¢ Change in voice.
Guruprasad Y, Chauhan DS. Deep lobe parotid gland
pleomorphic adenoma involving the parapharyngeal
space.Med J DY Patil Univ 2012;5:62-65
13. PRESTYLOID PPS TUMOR PRESENTATION
The Open Access Atlas of Otolaryngology, Head & Neck Operative Surgery by Johan Fagan (Editor)
johannes.fagan@uct.ac.za is licensed under a Creative Commons Attribution
15. TUMOUR PRESENTATION OF CAROTID SPACE
Asymptomatic
Neck mass behind the mandible, which can be pulsatile.
OSA
Symptoms of ET dysfunction/ unilateral OME.
Usually with a mass extending into upper lateral neck in the
lareral oropharynx .
Dysfunction of cranial nerve 9th to 12th.
Horners syndrome.
18. INFLAMMATORY LESIONS
ā¢ Odontogenic infection is most
commonly the source of an
inflammatory mass in the masticator
space.
ā¢ Cellulitis or abscess may form as a
complication of acute tonsillitis or
sialoadenitis.
ā¢ Infection can spread to other neck
spaces and to the mediastinum.
19. PRE OPERATIVE EVALUATION
ā¢ Imaging should always be used prior to surgery.
ā¢ MR angiography (MRA) may be added for a more precise diagnosis.
ā¢ radiological staging of the patient is completed by using a hybrid of positron
emission tomography(PET) and CT (PET/CT).
22. IMAGING
ā¢ Abnormality
ā¢ Origin and extend
ā¢ Vascularity
ā¢ Presence of fat in between planes
ā¢ Relationship to parotid gland
ā¢ Involvement of carotid
ā¢ Approach
23. TISSUE DIAGNOSIS
ā¢ tissue diagnosis is sensitive to differences
between benign and malignant Lesion.
ā¢ Fine needle aspiration (FNA) biopsy can be
performed via ultrasound, but frequently CT-
guided FNA,
ā¢ Exception: JNA
Paraganglioma
suspected vascular aneurysm.
Zell Ballan appearance of
paraganglioma, image source
24. OTHER INVESTIGATIONS
ā¢ plasma metanephrines or 24-hour
urine collection for catecholamines
and metanephrines.
ā¢ Routine blood investigations
ā¢ USG neck
ā¢ Xray to assess airway
ā¢ I/L or FOL to see vocal cord mobility.
27. PRINCIPLE OF SURGERY
ā¢ Pre-op airway assessment.
ā¢ Wide field exposure.
ā¢ Gentle dissection around the tumour to prevent rupture.
28. TRANS-ORAL APPROACH
ā¢ small benign neoplasms that originate in the PPS,
ā¢ The limitations are limited exposure, inability to visualize
the great vessels, an increased risk of facial nerve injury
and tumour rupture.
ā¢ for small benign salivary gland tumour
ā¢ combined with an external approach to mobilize lesions
with a oropharyngeal component.
29. TRANSCERVICAL APPROACH
Most preferred approach,
ā¢ Key structures: The cranial nerves, including the
hypoglossal, vagus, and spinal accessory
nerves, distal facial artery and vein need to be
ligated .
30. TRANSCERVICAL-TRANSPAROTID APPROACH
For tumours arising from the
deep lobe of the parotid,
the trans-cervical approach
can be combined with a
trans-parotid approach.
Involves dissection of facial
nerve and parotid, thus
extensive.
37. TORS
ā¢ 3 dimentional
ā¢ Better visualisation
ā¢ Gentle dissection
ā¢ Allows examination to space
around tumour
38. ā¢ The trans oral robotic approach is used for selected PPS tumors that are located anterior
to the carotid artery.
ā¢ radical tonsillectomy, and partial laryngectomy , tongue base neoplasms.
ā¢ Advantage:
no disfiguring facial scar.
no large external incisions to the patientās neck.
no malocclusion or malunion of the jaw.
no possibility of a separate procedure for hardware, plate, and screw removal.
less chance of infection.
39. TORS
ā¢ Disadvantage:
ā¢ The surgical procedure is technically
challenging and necessitates the training of
all levels of surgical personnel.
ā¢ Costly.
ā¢ Delicate microinstrument.