Meyer, who with coworkers' recently described the septal relationships of the suborbicularis fat pad, is entirely correct in pointing out a labeling error; the arrowhead on the figure indicates not the suborbicularis fat pad but rather the subcutaneous fat (which lies beneath the dermis and anterior to the orbicularis). However, I do not believe that the posterior shadow along the orbital rim in the Asian volunteer is a posteriorly located arcus marginalis. This posterior shadow is an orbital fibrous condensation that is occasionally seen on these images. On MRI we have noted that the orbital septum sometimes blends into the fibrous septa of the postorbicularis fat pad and is not always visualized as a discrete fibrous sheet, just as it is sometimes less distinct surgically. In this Asian eyelid, the orbital septum that separates the prominent suborbicularis fat and preaponeurotic fat is not well imaged, and the curved
Goldberg RA. Magnetic Resonance Imaging of the Upper Eyelid Anatomy-Reply. Arch Ophthalmol. 1994;112(10):1278. doi:10.1001/archopht.1994.01090220028011
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