The clinical landmark of infraorbital foramen in Chinese
population: a prospective measurement study
Raymond Wai-Man Ng
William Ignace Wei
Received: 23 April 2014 /Accepted: 4 June 2014 /Published online: 24 June 2014
Springer-Verlag Berlin Heidelberg 2014
Background Infraorbital nerve block canonlybeadministered
effectively with good knowledge of the location of the
infraorbital foramen (IOF). In this article, we will describe the
clinical landmark of the IOF with references to the infraorbital
rim (IOR), mid-pupillary line (MPL), and facial midline (FML).
Methods In our division, maxillary swing approach was
adopted for the access of the nasopharynx and skull base.
Through a Weber-Ferguson-Longmire incision, the maxilla
was freed from its bony connections and swung out to expose
the skull base. With this approach, the infraorbital foramen
and nerve were identified under direct vision. Prospective
measurements were taken intraoperatively on a series of pa-
tients who underwent maxillary swing operation. The dis-
tances between the IOF and various reference points (IOR,
MPL, and FML) were measured with caliper. Means, standard
deviations, and ranges were determined.
Results From April 2009 to October 2012, 30 patients were
included in this study. The locations of 30 infraorbital foram-
ina were analyzed. The distances between IOF and IOR,
MPL, and FML ranged from 8 to 12 (mean 9.6±1.3) mm, 4
to 14 (mean 9.3±2.4) mm, and 24 to 38 (mean 32.7±3.4) mm,
Conclusions To our knowledge, this is the first study in the
literature demonstrating the clinical landmark of IOF on living
persons and adopting MPL as a reference point. We believe
that the IOR and MPL are convenient reference points for the
accurate localization of IOF.
Level of Evidence: Level IV, diagnostic study.
Keywords Infraorbital foramen
The accurate localization of infraorbital foramen (IOF) is
important in facial surgery. The knowledge of IOF location
not only allows effective administration of infraorbital nerve
(ION) block but also helps to prevent inadvertent injury to the
ION during facial operations, e.g., facial fracture surgery and
cosmetic filler injection.
Cadaveric studies are available in the literature describing
the location of IOF with references to various soft and hard
tissue structures [1–10]. However, there are several shortcom-
ings, including the use of inconvenient reference points and
possible inaccurate measurement caused by the distortion of
soft tissue in cadavers. These lead to the search of a conve-
nient and accurate landmark of IOF.
The aim of this study is to find out the clinical landmark of
the IOF with references to infraorbital rim (IOR), mid-
pupillary line (MPL), and facial midline (FML).
Material and methods
In our division, maxillary swing was the approach of choice
for the access of the nasopharynx and skull base. The main
indication for the maxillary swing operation was the resection
of recurrent or residual nasopharyngeal carcinoma after radio-
Y. <W. Chan (*)
R. W.<M. Ng
W. I. Wei
Division of Plastic and Reconstructive Surgery/Head and Neck
Surgery, Department of Surgery, The University of Hong Kong
Queen Mary Hospital, Pokfulam, Hong Kong, SAR, China
Eur J Plast Surg (2014) 37:517–522