The maxillary artery and the lateral pterygoid muscle: the New Zealand story

Characterization of the pterygomeningeal artery based on branching pattern and muscular distribution

PURPOSE

The pterygomeningeal (accessory meningeal) artery arises from the middle meningeal or maxillary artery. Although there is the potential that this artery may be wounded by the surgery for the temporomandibular joint disorder, the current state of anatomical knowledge is insufficient. This study investigated the appearance and the branching pattern of this artery as a means to its characterization.

METHODS

The pterygomeningeal artery was dissected in 14 cadavers and its branches and their distributions to the muscles inside the mandible were examined.

RESULTS

The maxillary artery passed lateral to the lateral pterygoid muscle. The pterygomeningeal artery arose from the middle meningeal or maxillary artery. It ascended anteriorly and coursed medial or lateral to the mandibular nerve. It passed above the pterygospinous ligament and then descended. The ascending trunk gave some lateral branches to the lateral pterygoid muscle. The branches sometimes passed lateral to the mandibular nerve even if the pterygomeningeal artery coursed medial. The descending trunk was divided into middle and medial branches, which supplied the medial pterygoid muscle and the tensor veli palatini, respectively. The pterygomeningeal artery was sometimes equally bifurcate near the origin, and the counterparts passed lateral and medial to the mandibular nerve. The distributions of the medial and lateral counterparts were equivalent to those of the descending trunk and the lateral branches, respectively.

CONCLUSION

The pterygomeningeal artery contains three groups of muscular branches, which sometimes appear in a bifurcate form. Their positions relative to the mandibular nerve and the pterygospinous ligament characterize the artery; this information may help to avoid iatrogenic injury.

Systematic review and meta-analysis of the anatomy of the maxillary artery using the Anatomical Quality Assurance (AQUA) checklist

BACKGROUND

The maxillary artery (MA) is one of the terminal branches of the external carotid artery (ECA) and through its branches, it is responsible for vascularizing several organs and muscles of the head and neck, including their surrounding soft tissues, the oral and sinonasal cavities, dura mater, and various cranial nerves. The aim of this study was to conduct a systematic review and meta-analysis of maxillary artery anatomy according to the Anatomical Quality Assurance (AQUA) checklist.

METHODS

We conducted a systematic search through PubMed, EMBASE, Scopus, ScienceDirect, Web of Science, SciELO, Springerlink, WILEY and BIREME databases. We applied the Anatomical Quality Assurance (AQUA) checklist for analysis the methodological quality of the articles.

RESULTS

From a total of 11,759 articles found in the first search, and after applying the inclusion/exclusion criteria, in addition to eliminating duplicate articles, a final number of 24 articles were identified. The information on the maxillary artery was analyzed from each study regarding its course in relation to the lateral pterygoid muscle, the intra- and extraluminal diameters of the maxillary artery and its branches, and the types of branching of the maxillary artery in the pterygopalatine fossa.

CONCLUSION

From this study, it was possible to conclude the importance of anatomical knowledge of the maxillary artery, for its application in the clinical study of the head and neck, as well as the need to apply the AQUA checklist in the development of systematic anatomical reviews to ensure accurate reliability and a better assessment of the effect of anatomical publications.

Proximity of the middle meningeal artery and maxillary artery to the mandibular head and mandibular neck as revealed by three-dimensional time-of-flight magnetic resonance angiography

Purpose

The close topographic relationship between vascular and osseous structures in the condylar and subcondylar region and marked variability in the arterial course has been revealed by both imaging and cadaveric studies. This study aimed to verify the previously published information in a large sample and to determine a safe surgical region.

Methods

We analyzed the three-dimensional time-of-flight magnetic resonance angiography images of 300 individuals.

Results

The mean distance between the middle meningeal artery and the apex of the condyle or the most medial point of the condyle was 18.8 mm (range: 11.2–25.9 mm) or 14.5 mm (range: 8.8–22.9 mm) respectively. The course of the maxillary artery relative to the lateral pterygoid muscle was medial in 45.7% of cases and lateral in 54.3%. An asymmetric course was evident in 66 patients (22%). The mean distance between the maxillary artery and condylar process at the deepest point of the mandibular notch was 6.2 mm in sides exhibiting a medial course (range: 3.7–9.8 mm) and 6.6 mm in sides exhibiting a lateral course (range: 3.9–10.4 mm). The distances were significantly influenced by age, gender, and the course of the maxillary artery.

Conclusion

Our study emphasizes the marked inter- and intra-individual variability of the maxillary and middle meningeal arterial courses. We confirmed the proximity of the arteries to the condylar process. Extensive surgical experience and thorough preparation for each individual case are essential to prevent iatrogenic vascular injury.

The History and Evolution of Internal Maxillary Artery Bypass

Internal maxillary artery (IMA) bypass has gained momentum in the last 5 years for the treatment of complex cerebrovascular disorders and skull base tumors. However, some issues regarding this treatment modality have been proposed. As one of the most experienced neurosurgical teams to perform internal maxillary artery bypass in the world (>100 clinical cases), we reviewed the literature in aspects of basic anatomy of maxillary artery with its variations to the lateral pterygoid muscle, initial anastomosis modalities, and subsequent exposure techniques in cadaver studies, preoperative arterial evaluation methods, optimal interposed graft selections, and surgical outcome in the management of complex aneurysms, skull base tumors, and steno-occlusive disorders.

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.

Radiologic assessment of the relationship between the maxillary artery and the lateral pterygoid muscle

OBJECTIVE

The course of the second part of the maxillary can vary among different races. The aim of this study was to evaluate the relation between the maxillary artery and the lateral pterygoid muscle in a white population sample on computed tomographic (CT) angiograms.

MATERIALS AND METHODS

We retrospectively reviewed multidetector CT angiograms of 209 patients (134 men and 75 women). The images were taken using a 64-row multidetector CT scanner. The imaging parameters were 0.5 × 64-mm slice thickness, 0.5- or 0.3-mm increment, 120 kV, 250 mA s, 0.5-second rotation time, 0.641 pitch, and 512 matrix. The relationship between the pterygoid portion of the maxillary artery and the lateral pterygoid muscle was assessed on axial, sagittal, and coronal multiplanar reformatted images with the Vitrea 2 software program.

RESULTS

A total of 572 maxillary arteries in 286 patients were assessed. Of these maxillary arteries, 418 (68.42%) had a superficial course to the pterygoid muscle and 132 (31.58%) had a deep course. In 165 (78.94%) of 286 patients, there was a cross-lateral symmetry of the course of the artery; that is, both vessels were superficial or deep. In 44 (21.1%) of 209 patients, an asymmetric course was observed.

CONCLUSIONS

Because of the incidence of the asymmetric presentations, generalization regarding such a controversial topic should not be based on findings of cadaveric studies and each hemi head should be considered as a single entity. Therefore, advanced imaging systems are useful tools in preoperative planning and play a key role in the avoidance of hemorrhagic complications.