Modified transnasal endoscopic Lothrop procedure: further considerations.

The Lothrop procedure resects the medial frontal sinus floor, superior nasal septum, and intersinus septum to create a large frontonasal communication. However, the external approach often allowed medial collapse of soft tissue and stenosis of the nasofrontal communication. We describe a modified transnasal endoscopic Lothrop procedure in which drills are used for cases in which frontal recess exploration fails to relieve obstruction of the frontal sinus. The lateral bony walls are preserved, and medial collapse does not occur. The mucosa of the posterior table and posterior nasofrontal duct is preserved, and a single common frontal opening is created. We have found this approach to be safe and reliable. Fourteen patients have undergone this procedure without complication, achieving resolution or improvement of their symptoms and maintaining wide patency of the frontonasal opening. We recognize that long-term follow-up will be required but remain encouraged with our favorable results to date.