The Melbourne Classification of the Complete Unilateral Cleft Lip Based on Hypoplasia

Background: The hypoplastic lateral lip element within the cleft lip presentation is a recognized entity that has been recently shown to be more common on the right side. The spectrum of such change is yet to be defined. The authors propose the Melbourne classification system of cleft lip hypoplasia and see it as an important step towards discerning the relevance of these anatomical observations to the management of cleft lip/palate patients. Methods: This is a retrospective observational study of patients with complete unilateral cleft lips treated by the senior author (DKC) at the Royal Children's Hospital, Melbourne. Patient charts were retrospectively reviewed and patients were classified into different degrees of hypoplasia based on preoperative, intraoperative, and postoperative photography. Data was reported using descriptive statistics. Results: Fifty-nine patients with complete unilateral cleft lip deformity were grouped according to lateral lip element hypoplasticity. Twenty patients had right-sided clefts and 39 patients had cleft lips on the left side. Of those with right-sided clefts, 18 patients had evidence of hypoplasia (90%). Three patients had Type 1 deformities, 3 patients were Type 2, and 12 patients were Type 3. Patients with left-sided clefts were found to have hypoplasia less frequently with 15 patients showing evidence (38.5%). Conclusions: The authors report a classification system of hypoplasia involving the lateral lip element in complete unilateral cleft lip. The authors propose this classification system as a new measure of cleft severity that will have implications for patient expectations, surgical planning, and future outcome studies.