[Sphenopalatinum foramen: an anatomical study]

Morphological Description and Clinical Implication of Sphenopalatine Foramen for Accurate Transnasal Sphenopalatine Ganglion Block: An Anatomical Study

Objective:

Transnasal sphenopalatine ganglion block is a commonly used approach for treatment of a variety of headache disorders. However, no standard technique has yet been defined for this less invasive approach. In this study, our aim was to investigate morphometric and anatomical features of the sphenopalatine foramen, and to describe a more efficient approach for transnasal sphenopalatine ganglion block.

Method:

The present study was designed retrospectively. Ten cadaver semi- heads and 18 adult dry skulls (28 samples totally) were included in the study. The distances between the sphenopalatine foramen and palatum durum, and also between the sphenopalatine foramen and the spina nasalis anterior, angle of elevation of the sphenopalatine foramen from palatum durum, and the length and width of the sphenopalatine foramen were measured.

Results:

The mean width and length of the foramen were 3.79±0.35 and 6.44±0.94 mm, respectively. The mean distance between the palatum durum and the sphenopalatine foramen was 15.58±1.68 mm. The mean angle of elevation of the sphenopalatine foramen from the palatum durum was 26.10±3.97 degrees. The mean distance between the sphenopalatine foramen and the anterior nasal spine was 52.90±2.98 mm.

Conclusions:

In the transnasal sphenopalatine block, we suggest advancement of nasal applicator through superolateral direction for approximately 5.3 cm, and at an angle of about 26° from the nasal base..

Endoscopic and Three-Dimensional Radiographic Imaging of the Pterygopalatine and Infratemporal Fossae

Objectives:

We sought to define the surgical endoscopic anatomy of the pterygopalatine fossa (PPF) and infratemporal fossa (ITF) through endoscopic cadaver dissections and radiographic imaging analysis.

Methods:

Eleven fresh cadavers were submitted to computed tomography (CT) and endoscopic dissection. We used 3-dimensional (3-D) CT reconstruction and endoscopic video imaging for analysis of the bony and soft tissue landmarks. One fixed cadaver head was grossly dissected to confirm the endoscopic anatomic findings.

Results:

The CT and 3-D CT reconstruction measurements between the pterygoid canal and the foramen rotundum averaged 4.36 mm and 5.09 mm, respectively. An osseous ridge (pterygoid ridge) was identified on the anterior face of the pterygoid process as a novel identifiable anatomic landmark in all of the specimens. The average length of the pterygoid ridge on 3-D CT reconstruction was 7.84 mm. The internal maxillary artery entered the PPF posteromedial to the temporalis tendon and anterolateral to the lateral pterygoid muscle. The average distance from the anterior edge of the lateral pterygoid plate to the foramen ovale was 17.1 mm.

Conclusions:

The pterygoid ridge is a novel and reliable osseous landmark that could assist surgeons during endoscopic surgery on the PPF and ITF. The neurovascular and muscular anatomic relationships were characterized for both the PPF and the ITF.

Endoscopic localization of the sphenopalatine foramen: do measurements matter?

The objective of this study was to evaluate different methods and measurements for localization of the sphenopalatine foramen (SPF) during endoscopic transnasal exposure. The study design consisted of descriptive anatomical study and the setting was in Microsurgical Cadaver Dissection Lab. Sixteen lateral nasal walls were dissected endoscopically to identify and localize the SPF. Multiple measurements were obtained from nasal sill (NS) to SPF, ethmoid crest (EC), and other related landmarks. The results showed that EC was identified in all sides with different degrees of projection. SPF extended below the inferior edge of EC, i.e., lying both in the superior and middle meatus, in 12 sides (75 %), while it was laying only in the superior meatus in 4 sides (25 %). An accessory foramen was identified in 3 sides (18.7 %), all of which were located in middle meatus. The distance from NS to SPF ranged widely from 55 to 76 mm (mean ± SD 64.4 ± 6 mm). The average angle of elevation formed between SPF to NS and nasal floor was 11.4° (range 11-12°). Although many previous studies have reported measurements to SPF, we do not believe these measurements are of practical help due to the wide range of measurements and the lack of standard reference points. The main constant landmark for SPF remains the EC. Since SPF frequently extends below EC, the mucoperiosteal flap should be extended below the inferior edge of this crest to avoid missing the middle meatal part of SPF or any accessory foramina.

Anatomical and surgical study of the sphenopalatine artery branches

The sphenopalatine artery gives off two main branches: the posterior lateral nasal branch and the posterior septal branch. From 2007 to 2012 17 patients were treated with cauterization and/or ligature of the sphenopalatine artery with endonasal endoscopic approach. 90 nasal dissections were performed in 45 adult cadaveric heads. We evaluated the number of branches emerging from the sphenopalatine foramen and the presence of an accessory foramen. In the surgery group, we observed a single trunk in 76% of the patients (13/17) and a double trunk in 24% (4/17). We found an accessory foramen in four cases. We obtained a successful result in bleeding control in 88% of the cases. In the cadaver dissection group, 55 nasal cavities had a single arterial trunk (61%), 30 had 2 arterial trunks (33%) and in only 5 nasal fossae we observed 3 arterial trunks (6%). We were able to dissect four accessory foramina. We suggest that in most cases only one or two branches are found in the sphenopalatine foramen.

Management of intractable spontaneous epistaxis

BACKGROUND

Epistaxis is a common otolaryngology emergency and is often controlled with first-line interventions such as cautery, hemostatic agents, or anterior nasal packing. A subset of patients will continue to bleed and require more aggressive therapy.

METHODS

Intractable spontaneous epistaxis was traditionally managed with posterior nasal packing and prolonged hospital admission. In an effort to reduce patient morbidity and shorten hospital stay, surgical and endovascular techniques have gained popularity. A literature review was conducted.

RESULTS

Transnasal endoscopic sphenopalatine artery ligation and arterial embolization provide excellent control rates but the decision to choose one over the other can be challenging. The role of transnasal endoscopic anterior ethmoid artery ligation is unclear but may be considered in certain cases when bleeding localizes to the ethmoid region.

CONCLUSION

This article will focus on the management of intractable spontaneous epistaxis and discuss the role of endoscopic arterial ligation and embolization as it pertains to this challenging clinical scenario.