Mohler Unilateral Cleft Lip Repair: Surgical Tutorial for Professionals

A left unilateral complete cleft lip is repaired with the Mohler technique, which employs rotation advancement principles to guide repair.

This tutorial for medical professionals was developed to supplement learning of a common surgical technique and is not intended to replace formal surgical training.

This slideshow is primarily intended for use on tablets or larger screens. Some detail might be lost on mobile screens.

This surgical tutorial illustrates the steps in Mohler unilateral cleft lip repair.

Mark the trough (nadir) of cupid’s bow. You may evert the lip and look at the frenulum as another midline reference.

Mark the peak of cupid’s bow on the non-cleft side (on each side of the thickness of the white roll).

Mark the trough (nadir) of cupid’s bow.

Measure the distance between these points and transpose to create the other peak of cupid’s bow.

The wet-dry border on the vermilion is marked perpendicular to each point that was marked on the white roll.

Mark the midline at the columellar base.

Mark the height of philtral columns at the columellar base.

Measure lip height differential. The cleft side lip shortening will be lengthened in this technique by 1) the Mohler columellar back cut, 2) the curvilinear Rose-Thompson effect, and 3) the cutaneous back cut.

The Mohler back cut is designed as an equilateral triangle (approximately 2mm on each side) on the columella and provides 1-2mm of lip and columellar lengthening. Mark two symmetric points at the columellar base between the midline dot and the height of the philtral columns.

Mark the height of the back cut, 2mm up from the columellar base.

Mark each alar base. Care is taken to put these markings at the same anatomic point – the cleft side alar base is significantly distorted and can easily be mis-marked.

Mark Noordhoff’s point on the lateral lip element. It is chosen where the white roll has its full thickness and where the vermillion has near full substance.

Mark this small triangle with the necessary base width to further lengthen the shortened medial lip.

Design a corresponding back cut at the white roll on the medial lip. This is typically at a 45 degree angle from the white roll.

The cutaneous triangle and back cut are illustrated here.

Mark the cleft side nasal sill.

Mark the wet-dry border on each side. A narrowing of the dry vermillion is typically noted on the medial lip element. This will be augmented with a triangle from the lateral lip.

Based on the difference in height of the dry vermillion on the medial lip element, design a vermillion triangle with a base that wide at the wet-dry junction on the lateral lip.

The medial lip element incision is designed perpendicularly across the white roll. This incision runs up to the columella and the planned back cut is created. A back cut in the vermillion will receive the triangle from the lateral lip.