[Post-operative cyst and orbital walls: a CT image analysis]

Area of Science:

• Ophthalmology
• Oral and Maxillofacial Surgery
• Radiology

Background:

• Post-operative cysts of the maxilla can potentially affect adjacent orbital structures.
• Understanding the relationship between these cysts and orbital wall integrity is crucial for patient outcomes.

Purpose of the Study:

• To analyze orbital wall affections secondary to post-operative maxillary cysts using coronal CT imaging.
• To correlate the location and type of orbital wall affection with clinical signs and symptoms.

Main Methods:

• Retrospective analysis of 109 cases with post-operative maxillary cysts using coronal CT scans (1982-1988).
• CT images were divided into five planes, 5mm apart, posterior to the nasion.
• Orbital walls were classified (inferior, medial, transition), and affections categorized (dehiscence, thinned-out, normal).
• Orbital signs and symptoms were assessed via patient questionnaires.

Main Results:

• Inferior orbital wall affections (dehiscence, thinning) were most prevalent (57%) at the third plane (2cm posterior to the nasion).
• Approximately 50% of cases exhibited orbital signs and symptoms, with 20% experiencing severe symptoms (visual loss, diplopia, exophthalmos).
• A significant correlation was found between the anteriority of the orbital affection and the incidence/severity of symptoms.
• Grave symptoms occurred when the orbital floor was affected 2-2.5cm posterior to the nasion, involving the inferior rectus muscle.

Conclusions:

• Post-operative maxillary cysts commonly cause orbital wall affections, particularly affecting the inferior orbital wall.
• The location of the orbital wall affection is a key predictor of associated clinical signs and symptoms.
• Early detection and management of orbital wall involvement are essential to prevent severe visual complications.