Usama F. Kamel,
A 34 years old man presented to the ophthalmology and ENT departments complaining of mild bulge of his right eye and mild symptoms of sinusitis. He complained of no sinus or eye pains, double vision, or deterioration of eyesight. He had neither trauma nor previous operations. His eye exam showed no exophthalmos. His endoscopic nasal examination showed no abnormality. He had normal eye movement with no diplopia. CT scans showed evidence of maxillary sinus opacification worse on left side. MRI scan confirmed dehiscent lamina papyracea and shortened thickened medial rectus muscle on the left side. He was diagnosed with incidental dehiscent lamina papyracea on the left side. Incidental dehiscent lamina papyracea is not uncommon, ranging between 0.5 - 10% in the general population. Medial rectus muscle is usually shortened (noted on axial views) and thickened (noted on coronal views). This case highlights the pitfall of symptom approach to the problem. This patient had consistently complained of right eye protrusion. The focus on his history, examination, CT and MRI investigations were on the right eye. In fact, the abnormality was indrawn left eye due to dehiscent lamina papyracea. His left eye was mildly enophthalmic compared to the right. Careful preoperative scan checking is crucial to identify landmarks and abnormalities.