Case of the week Details

• Enlarged and edematous left tonsil with fluid collection in the left tonsillar fossa and the left tonsillar
• At the level of the oropharynx, there is significant luminal compromise. The collection and edema extend to involve the left para-laryngeal soft tissues and the left vocal cord.
• Extension of fluid with mass effect into the left parapharyngeal space and along the left lateral wall of the oropharynx and hypopharynx up to the level of the cricoid.

DIAGNOSIS:

• Left peritonsillar abscess (Quinsy) with extensive extension into the left parapharyngeal space. 

Discussion:

• Patients often present to the emergency department with a wide variety of nontraumatic infectious, inflammatory, and neoplastic conditions of the head and neck.
• Potentially life-threatening conditions include
  1. Oral cavity infections
  2. Tonsillitis and peritonsillar abscess
  3. Sialadenitis & parotiditis
  4. Thrombophlebitis
  5. Periorbital and orbital cellulitis 
  6. Infectious cervical lymphadenopathy.
  7. Less common conditions include epiglottitis, invasive fungal sinusitis, angioedema, and deep neck abscess
• Modalities for diagnosis:
• Ultrasound has low sensitivity for deep neck infections; however can be utilized in emergency setting.
• CT is the first-line imaging modality in the emergency setting.
• Magnetic resonance imaging plays an important secondary role due to superior soft-tissue contrast.
• Routes of spread:
• Tonsillitis suppurates and internally cavitates to create an intratonsillar abscess; however, a true tonsillar abscess is rare. 
• The infection penetrates the tonsillar capsule and the peritonsillar space—a potential space between the tonsillar capsule and the superior constrictor muscle
• The infection may then continue to extend into the parapharyngeal, masticator, or submandibular space. 
• The resulting peritonsillar cellulitis resolves over several days; however, if it goes untreated, a peritonsillar abscess develops, typically along the superior tonsillar pole.

Imaging features 

• Ultrasound features 
• Mild hypoechoic collection is anteromedial to the internal carotid artery.
• Probe pressure may elicit movement of the debris within the abscess
• Color flow or power Doppler may demonstrate circumferential hyperemia.

• CT features peritonsillar cellulitis 
• Tonsillar enlargement 
• Linear, striated enhancement of the palatine tonsils and posterior pharyngeal soft tissues 
• Medial apposition of the enlarged tonsils resulting in a “kissing tonsils” appearance. 
• Central liquefaction surrounding him like enhancement is diagnostic of peritonsillar abscess.
• Fluid collection dissecting along multiple planes as in our case.

REFERENCES:

1. Emergency Imaging Assessment of Acute, Nontraumatic Conditions of the Head and Neck Erin Frankie Capps, James J. Kinsella, Manu Gupta, Amol Madhav Bhatki, and Michael Jeffrey Opatowsky. RadioGraphics 2010 30:5, 1335-1352
2. Ong YK, Goh YH, Lee YL. Peritonsillar infections: local experience. Singapore Med J. 2004;45 (3): 105-9. 

Dr. Sushant Mittal MD
Cross-sectional Fellow
Columbia Asia Radiology Group.

Dr Anita Nagadi MD, MRCPCH, FRCR
Senior Consultant Radiologist
Columbia Asia Radiology Group.