Pterygopalatine Fossa: Microsurgical Anatomy and its Relevance for Skull Base Surgery

Introduction The purpose of this study was to define the anatomical relationships of the pterygopalatine fossa (PPF) and its operative implications in skull base surgical approaches. Methods Ten cadaveric heads were dissected at the Dianne and M Gazi Yasargil Educational Center MicrosurgicaLaboratory, in Little Rock, AK, USA. The PPF was exposed through an extended dissection with mandible and pterygoid plate removal. Results The PPF has the shape of an inverted cone. Its boundaries are the pterygomaxillary fissure; themaxilla, anteriorly; themedial plate of the pterygoid process, and greater wing of the sphenoid process, posteriorly; the palatine bone,medially; and the body of the sphenoid process, superiorly. Its contents are the maxillary division of the trigeminal nerve and its branches; the pterygopalatine ganglion; the pterygopalatine portion of the maxillary artery (MA) and its branches; and the venous network. Differential diagnosis of PPF masses includes perineural tumoral extension along the maxillary nerve, schwannomas, neurofibromas, angiofibromas, hemangiomas, and ectopic salivary gland tissue. Transmaxillary and transpalatal approaches require extensive resection of bony structures and are narrow in the deeper part of the approach, impairing the surgical vision and maneuverability. Endoscopic surgery solves this problem, bringing the light source to the center of the surgical field, allowing proper visualization of the surgical field, extreme close-ups, and different view angles. Conclusion We provide detailed information on the fossa's boundaries, intercommunications with adjacent structures, anatomy of the maxillary artery, and its variations. It is discussed in the context of clinical affections and surgical approaches of this specific region, including pterygomaxillary disjunction and skull base tumors.

Assessment of the lateral pterygoid plate fractures during Le Fort I osteotomies regarding the angulation of the osteotome.

AIM. This study aimed to clarify the relation between the angulation of the curved osteotome and fracture of the pterygoid plate during Le Fort I osteotomy. MATERIAL AND METHODS. Twenty-one specimens of hemisectioned Turkish skulls were used for the study. The maxilla was sectioned transversely on the floor of the pyriform aperture and posteriorly to the lateral pterygoid plate with a mechanical saw. The pterygomaxillary junction was separated with a curved osteotome by angulating the osteotome with, 0° and -30° to the occlusal plane. The undesired fractures of the lateral pterygoid plate were determined. Among 21 specimens, 7 pterygomaxillary junctions were separated with an angle of +30° , 7 with 0° and 7 with -30° to the occlusal plane. RESULTS. In group +30°, the undesired fracture occured in 6 of the cases. In group -30°, the undesired fracture was determines in one case. In cases where the separation was performed by placing the osteotome paralell to the occlusal plane all plates remained safe. CONCLUSION. Within the limited knowledge of the current study it can be concluded that the osteotome should be placed paralell to the occlusal plane.

Lateral pterygoid plate fractures associated with mandible fractures.

IMPORTANCE: Classically, pterygoid plate fractures have been associated with fractures of the mid-face and skull base. When isolated pterygoid plate fractures are identified on imaging that only extends to the level of the skull base, other related facial fractures may be missed. We sought to evaluate isolated lateral pterygoid plate fractures on computed tomography (CT) scans in conjunction with mandible fractures and to propose a mechanism of fracture unrelated to the classic dissociating mid-face Le Fort fractures. OBSERVATIONS: In this retrospective case series, 7 patients who sustained facial trauma from 2006 to 2012 were found to have isolated lateral pterygoid plate fractures. All patients had an ipsilateral subcondylar fracture, 2 had symphyseal fracture, 2 had body fracture, and 1 had coronoid fracture. CONCLUSIONS AND RELEVANCE: On the basis of these cases, isolated lateral pterygoid fractures noted on CT of the head may be suggestive of an unappreciated mandibular fracture. The suspected mechanism is due to force transduction through the medial and lateral pterygoid muscles when acute displacing force is placed on the mandible. In patients with identified isolated pterygoid plate factures, a dedicated CT of the mandible may be indicated to assess for associated mandibular fracture, even in patients whose clinical examinations have had negative results.

Sinusitis maxilar derecha, fractura de suelo de órbita y de la apófisis Pterigoides como complicación inusual en la exodoncia de un tercer molar superior derecho incluido. A propósito de un caso / Right maxillary sinusitis, fracture of orbital floor and of the pterygoid process as an unusual complication in the extraction of an impacted upper right third molar. A case report

La cirugía del tercer molar incluido no está exenta de complicaciones. Estas pueden ser: intraoperatorias, mediatas o tardías. En el caso que se presenta se expone una complicación inusual en la exodoncia del tercer molar superior, una sinusitis maxilar derecha, fractura de suelo de órbita y de la apófisis pterigoides de forma accidental por el desplazamiento del luxador al interior del seno maxilar durante la exodoncia quirúrgica del tercer molar superior derecho (AU)

The surgery of the impacted third molar isnot exempted from complications. These can be: intraoperative, mediate or late. In the event it arises, it presents an unusual complication in the extraction of the upper third molar, right maxillary sinusitis, accidental fracture of the orbital floor and pterygoid process due to the displacement of the luxator to the interior of the maxillary sinus during the surgical extraction of the upper right third molar (AU)