Pterygopalatine Fossa Approach

The pterygopalatine fossa (PPF) is a small but complex anatomical space located posterior to the maxillary sinus and anterior to the pterygoid process. It acts as a neurovascular crossroads and is increasingly accessed via endoscopic endonasal transpterygoid approaches in neurosurgery and skull base surgery.

Endonasal access to the PPF is indicated in the following scenarios:

• Tumors involving:
  • PPF (schwannomas, carcinomas)
  • Infratemporal fossa
  • Lateral sphenoid sinus
  • Parasellar region (Knosp III–IV adenomas)
• Management of vascular lesions:
  • Juvenile nasopharyngeal angiofibroma
  • Arteriovenous malformations
  • Severe posterior epistaxis
• Neuralgia management:
  • Vidian nerve neuralgia
  • Sluder’s syndrome
• Rare cases:
  • Abscess drainage (deep face spaces)

The endonasal transpterygoid approach involves the following steps:

1. Medial maxillectomy (partial or complete)
2. Identification and resection of the posterior wall of the maxillary sinus
3. Removal of pterygoid process (partial)
4. Exposure of PPF and its contents

• Maxillary nerve (V2) — passes through the foramen rotundum
• Infraorbital nerve — lateral to infraorbital artery
• Greater palatine nerve — medial to the descending palatine artery
• Vidian nerve — runs through the pterygoid canal
• Pterygopalatine ganglion — located anterior to the vidian nerve, medial to V2
• Sphenopalatine artery — a key vessel supplying the nasal cavity

Recent anatomical data from a cadaveric study (Akdemir Aktaş et al., 2025):

• Maxillary nerve: ~15.93 ± 6.19 mm (length), 3.96 ± 0.69 mm (diameter)
• Infraorbital nerve: ~24.4 ± 4.38 mm / 3.00 ± 0.71 mm
• Greater palatine nerve: ~13.15 ± 4.25 mm / 2.70 ± 0.39 mm
• Vidian nerve: ~16.78 ± 1.18 mm / 2.15 ± 0.51 mm
• Pterygopalatine ganglion: ~4.59 mm wide / 5.18 mm tall

→ These metrics are useful for navigation, instrument reach, and avoiding complications.

• Injury to the internal maxillary artery or its branches → bleeding
• Neuropathic pain syndromes due to nerve damage
• Cerebrospinal fluid leak if extended laterally toward the skull base
• Diplopia from injury to branches of the abducens nerve (in more extended routes)

1. Akdemir Aktaş H, et al. *Endoscopic endonasal approach to the nerves of the pterygopalatine fossa: a detailed cadaveric anatomical study*. Surg Radiol Anat. 2025; 47(1):122. doi:10.1007/s00276-025-03637-5.

TIP: Consider neuronavigation, especially in tumors with lateral or superior extension, and preoperative CTA if vascular involvement is suspected.