PhiliPPine Journal of otolaryngology-head and neck Surgery                                                          Vol. 24 no. 2 July – december 2009   

40  PhiliPPine Journal of otolaryngology-head and neck Surgery

FROM THE VIEWBOX

Figure. 1 Coronal CT image passing through the level of the osteomeatal complex in a 
patient with severe nasal polyposis.  Arrows point to a retroverted uncinate process on 
both sides. Recognition of this anatomic abnormality is essential for the determination of 
surgical landmarks for endoscopic sinus surgery.

REFERENCES 
1. Bolger WE.  Paranasal sinus bony anatomic variations and mucosal abnormalities: CT 

analysis for endoscopic sinus surgery.  Laryngoscope 101:56-64, 1991.
2. Freedman HM, Kern EB. Complications of intranasal ethmoidectomy: a review of 1000 

consecutive operations. Laryngoscope 89:421-34, 1979.

Considerable attention has been directed toward analysis of paranasal sinus 
anatomy through coronal plane computerized tomographic (CT) imaging in this age of 
functional endoscopic sinus surgery.  Recently, it has become apparent that anatomic 
variations are also evident on CT analysis of patients.  Subtle anatomic features can now 
be imaged through CT, with a level of clarity previously not afforded by standard sinus 
radiographs.1

The key to a successful endoscopic sinus surgery is the proper identification of 
landmarks, and intelligent decision-making should there be any doubts as to what 
structure lies ahead.  The middle turbinate is the main landmark in the region and should 
be preserved if possible.  Attention to the limits of the middle turbinate landmark is one 
of the keys to uncomplicated surgery.2   The presence of a retroverted uncinate process, 
wherein the uncinate process ( rather than the middle turbinate) is the first bone to 
encountered, can be misleading to the rhinologic surgeon and lead to inadequate 
surgery.  Familiarity with anatomic variations such as the retroverted uncinate process 
should increase the safety and effectiveness of functional endoscopic sinus surgery. 

Retroverted Uncinate Process: 
An Anatomic Variation

Armando T. Isla Jr., MD
Josefino G. Hernandez, MD

Department of Otorhinolaryngology
College of Medicine – Philippine General Hospital
University of the Philippines Manila

Correspondence: Armando T. Isla Jr., MD
Department of Otorhinolaryngology
Ward 10, Philippine General Hospital
Taft Avenue, Ermita, Manila 1000
Philippines
Phone: (632) 526 4360
Fax: (632) 525 5444
Email: donisla.md@gmail.com
Reprints will not be available from the author. Philipp J Otolaryngol Head Neck Surg 2009; 24 (2): 40 c  Philippine Society of Otolaryngology – Head and Neck Surgery, Inc.