Tip for preventing chemosis after swinging eyelid procedure.

The swinging eyelid procedure, which was first described by C. D. McCord, Jr in 1981 ( McCord, 1981 ), is now the first-line approach to reach the inferior and lateral orbits ( Mourits et al., 2009 ). Although few complications are reported in relation to this approach, a chemosis is occasionally encountered after this procedure ( Mourits et al., 2009 ) ( Figure 1 ). How can this complication be avoided? The answer lies in an appreciation of the location and depth of the lymphatic vessels of the cheek. In general, as the lymphatic vessels are situated in the same layer with veins, they take a course under the superficial musculoaponeurotic system (SMAS) in the cheek area ( Dutton, 1994 ). Although some important structures such as arteries and the facial nerve are located in this sub-SMAS layer (Zide, 2006), we need to recognise the lymphatic vessels also running in this layer. Therefore, dissection under the SMAS layer, namely, dissection of the soft tissue in front of the zygoma, possibly injures the lymphatic vessels, causing postoperative chemosis. Although such a chemosis generally subsides and minimal dissection under the SMAS layer did not cause significant chemosis, to know the mechanism of this complication is necessary. Thus, if the dissection is carried under the periosteum, instead of large undermining of the sub-SMAS layer, the lymphatic architecture remains almost undisturbed, and chemosis is reduced to a minimum.