Background: Lipomas can be categorized into deep and superficial lipomas according to anatomical depth. Many cases of forehead lipomas are reported to be deep to the muscle layer. We analyze ultrasound in delineating depth of forehead lipomas.
Methods: A retrospective review was performed for all patients who underwent excision of forehead lipomas between January 2008 and March 2013 and for whom preoperative ultrasound study was available. Sensitivity and specificity of ultrasound imaging was evalauted against depth finding at the time of surgical excision.
Results: The review identified 42 patients who met the inclusion criteria. Preoperative ultrasound reading was 18 as deep lipomas and 24 as superficial. However, intraoperative finding revealed 2 of the 18 deep lipomas to be superficial and 13 of the 24 superficial lipomas to be deep lipomas. Overall, ultrasonography turned out to be 69% (29/42) accurate in correctly delineating superficial versus deep lipomas.
Conclusion: Lipomas of the forehead tend to be located in deeper tissue plane compared to lipomas found elsewhere in the body. Preoperative ultrasonography of lipomas can be helpful, but was not accurate in identifying the depth of forehead lipomas in our patient population. Even if a forehead lipoma is found to be superficial on ultrasound, operative planning should include the possibility of deep lipomas.
Keywords: Forehead; Lipoma; Ultrasonography.