Retropharyngeal and Parapharyngeal Abscess

Abscess of pharyngomaxillary or lateral pharyngeal space is also known as parapharyngeal abscess.

Infection can come to this space from acute or chronic infections of tonsils and adenoids, bursting of peritonsillar abscess, dental infection of lower third molar teeth, Bezold’s abscess, petrositis, infections of parotid, retropharyngeal, and submaxillary spaces, injuries of neck etc.

Fever, odynophagia, sore throat, torticoilis and signs of toxemia may develop.

Retropharyngeal abscess lies anterior to the prevertebral fascia.

• Retropharyngeal space lies anterior to prevertebral fascia. It is the space between the buccopharyngeal fascia covering pharyngeal constrictor muscles and the prevertebral fascia. The space is divided into two lateral compartments (space of Gillette) by a fibrous raphe. Thus abscess of this space causes paramedian swelling in posterior pharyngeal wall.
• Each lateral space contains retropharyngeal nodes which disappear by 3-4 yrs of age. So abscess is commonly seen in chidren < 3 yrs of age.
• It is the prevertebral space which lies behind the prevertebral fascia. Abscess of this space produces midline swelling.
• The retropharyngeal abscess obstructs the aero digestive tract causing dysphagia, odynophagia, dyspnea, trismus etc.
• Treatment is incision and drainage

Clinical features of retropharyngeal abscess:

• Usually occurs in infants and young children, typically aged between 2 and 6 years.
• Infection of the upper respiratory tract leads to pyogenic adenitis of the retropharyngeal lymph nodes. The resulting abscess is limited to one side of the midline by a median raphe and anterior to the prevertebral fascia.
• A sore throat with dysphagia or odynophagia (including for saliva) will be present along with high pyrexia.
• Palpation of the posterior pharyngeal wall may confirm the diagnosis of a retropharyngeal abscess.

The parapharyngeal space (also termed the lateral pharyngeal space), is apotential space in the head and the neck. It has clinical importance in otolaryngology due toparapharyngeal space tumours and parapharyngeal abscess developing in this area.

• Ans.A. Pharyngomaxillary abcess
• In pharyngomaxillary/parapharyngeal abscess, the lateral pharyngeal wall is pushed medially.
• In retropharyngeal and prevertebral abscess, the posterior pharyngeal wall is pushed anteriorly.
• In peritonsillar abscess there is no bulging of the pharyngeal wall, only the tonsil is pushed medially.

Styloid process divides the pharynx into anterior and posterior compartment.

Trismus occurs in infection of anterior compartment whereas torticollis (due to spasm of paravertebral muscles) occurs in the infection of posterior compartment.

• Chronic retropharyngeal abscess is associated with caries of cervical spine or tuberculous infection of retropharyngeal lymph nodes secondary to tuberculosis of deep cervical nodes (i.e. suppuration of Rouviere nodes)
• It leads to discomfort in throat, dysphagia, fluctuant swelling of postpharyngeal wall.
• Retropharyngeal abscess does not lead to psoas spasm.

Treatment

• Incison and drainage of abscess
• Full course of ATT 

Retropharyngeal space lies behind the pharynx between the buccopharyngeal fascia covering pharyngeal constrictor muscles and the prevertebral facia (i.e. behind the pharynx and in front of prevertebral fascia)

On physical examination, may reveal bulging of the posterior pharyngeal wall.

Dysphagia and difficulty in breathing are prominent symptoms as the abscess obstructs the air and food passages

M/C cause acute retropharyngeal abscess in children is suppuration of retro pharyngeal lymphnodes secondary to infection of adenoids, nasopharynx and nasal cavity.

The M/C cause of acute retropharyngeal abscess in adutls is penetrating injury of posterior pharyngeal wall or cerivcal esophagus.