Radioanatomic Study of the Greater Palatine Canal Relevant to Endoscopic Endonasal Surgical Landmarks

Radiological examination of greater palatine canal medial wall dehiscence

INTRODUCTION

The greater palatine canal (GPC) connects the pterygopalatine fossa to the greater palatine foramen and houses vital neurovascular structures, which provide sensory innervation and circulation to the gums, palate, and nasal cavity. The GPC is of great clinical importance to various medical specialties; however, the anatomical variability of the GPC poses a risk of iatrogenic injury and complications. Therefore, understanding the normal anatomy and variations of the GPC is crucial for identifying vital structures and minimizing risks in clinical practice.

PURPOSE

The aim was to fill a gap in the current literature by focusing on the prevalence of GPC medial wall dehiscence, a lesser-known anatomic variation, in radiological scans.

METHODS

A total of 200 head and neck CT scans were examined, where 71 scans met the inclusion criteria. Statistical significance for incidence of GPC medial wall dehiscence, in reference to sex and side, was measured.

RESULTS

The GPC medial wall dehiscence was observed in 69% of scans. Bilateral dehiscence was seen in 57.7% of scans, while right-sided and left-sided unilateral dehiscence were found in 14.1% and 11.3%, respectively. Significant difference was found between the incidence of bilateral dehiscence compared to the absence of dehiscence.

CONCLUSION

Previous studies have highlighted the potential risks associated with invasive procedures involving the GPC. The clinical relevance of GPC medial wall dehiscence lies in the increased risk of transecting the contained neurovascular bundle. The presence of dehiscence emphasizes the need for meticulous preoperative radiologic analysis to tailor surgical approaches to individual patient anatomy.

Exploring Anatomical Variations in the Bony Architecture of the Greater Palatine Canal in Dry Bones

Introduction The greater palatine canal (GPC) holds significant clinical importance due to its role in providing access to the branches of the maxillary division of the trigeminal nerve. Anatomical variations within this posterior maxillary region can complicate the surgical anatomy, making the identification of vital structures challenging. Therefore, a thorough understanding of both normal anatomy and common anatomical variations of the GPC is essential to minimize perioperative complications during surgical procedures. This study aims to investigate the bony architecture of the GPC in dry bones to identify anatomical variations and address significant lacunae in our current understanding of this structure. Despite its impact on the management of various dental and surgical procedures, there remains a limited and sometimes inconsistent knowledge of the normal and variant anatomy of the GPC. Existing literature often lacks comprehensive detail regarding the range of anatomical variations and their implications for surgical approaches. By systematically documenting these variations, this study aims to bridge these gaps in knowledge, justify the need for continued research in this area, and highlight its potential clinical implications. Materials and methods In total, 30 dried and intact adult skull specimens were selected, consisting of 19 males (63.3%) and 11 females (36.7%). The selection criteria included an intact hard palate with fully erupted third molars and an intact lateral nasal wall on both sides. The presence of erupted third molars was used to assess the degree of bone resorption, ensuring that only specimens with minimal bone loss were included. The exclusion criteria ruled out specimens with major craniofacial deformities, excessive bone resorption, and signs of advanced age. The bony walls of the GPC were observed by passing a black wire made of rubber material with a consistent diameter (approximately 5 mm), allowing us to qualitatively assess the bore of the canal. Results In four out of 30 specimens (13.3%), significant variations were noted in the bony medial wall of the GPC. Of these, three specimens were male (75%) and one was female (25%). These variations have been categorized into four distinct types for clarity and analysis. Type 1, in a male specimen, showed a deficiency in the lower segment of the bony medial wall of the left GPC above the greater palatine foramen. Type 2, in a male specimen, had a small bar of bone in the left GPC midway between the foramen and the pterygopalatine fossa. Type 3, in a female specimen, exhibited a small bar of bone above the greater palatine foramen on the right side, with no wall above it. Type 4, in a male specimen, displayed a bar of bone above the greater palatine foramen on the right side, with the medial wall completely absent on the left side. Conclusion The study identified anatomical variations in the bony architecture of the GPC based on dry bone specimens. While these findings offer insights into potential variations that could affect surgical procedures, their clinical implications need validation through patient-based studies. Understanding these variations is crucial for improving preoperative planning and reducing surgical risks, but recommendations should be cautious given the limited sample size. Further research with larger samples and clinical validation is needed to fully understand the embryological basis and potential impact on surgical practice.

Anatomy of the greater palatine foramen and canal and their clinical significance in relation to the greater palatine artery: a systematic review and meta-analysis

PURPOSE

Accurate knowledge of greater palatine foramen (GPF) and greater palatine canal (GPC) anatomy is necessary to avoid injury to the greater palatine artery (GPA) when performing a variety of anesthesiologic, dental or surgical procedures. The aim of this paper was to perform a systematic review and meta-analysis of literature on the anatomy and localization of bony structures associated with the GPA, namely the GPF and GPC.

METHODS

A systematic literature search was performed using PubMed, Embase, ScienceDirect, and Web of Science databases. Seventy-five studies were included in the meta-analysis (n = 22,202 subjects).

RESULTS

The meta-analysis showed that the GPF is positioned 17.21 mm (95% CI = 16.34-18.09 mm) from the posterior nasal spine, 2.56 mm (95% CI = 1.90-3.22 mm) from the posterior border of the hard palate, 46.24 mm (95% CI = 44.30-48.18 mm) from the anterior nasal spine, 15.22 mm (95% CI = 15.00-15.43 mm) from the midline maxillary suture, 37.32 mm (95% CI = 36.19-38.45 mm) from the incisive foramen, and opposite the third maxillary molar (M3) in 64.9% (58.7-70.7%) of the total population.

CONCLUSION

An up-to-date, comprehensive analysis of GPF and GPC clinical anatomy is presented. The results from this evidence-based anatomical study provides a unified set of data to aid clinicians in their practice.