CHICAGO – Canthopexy and canthoplasty are simple, minimally invasive procedures that are often overlooked when treating periorbital aging, Dr. Cameron D. Chesnut said at the annual meeting of the American Society for Dermatologic Surgery.
Dr. Cameron Chesnut
“In a simple procedure you can do in the office in literally 5 or 10 minutes under local anesthesia, you can restore the integrity of the lower lid, which in addition gives some improvement in the upper lids by lifting the globe back up,” he said.
Canthopexy and canthoplasty are very commonly performed with blepharoplasty, but can be useful on their own or in combination with fillers in mild cases of retinacular aging or lower-lid ectropion where you don’t need or want a true, full-blown blepharoplasty.
There is a labyrinth of connective tissues attached to Whitnall’s tubercle and as patients age, there is laxity of the septum, retinaculum, and orbicularis; rounding of the lateral canthal angle; and a negative intercanthal tilt that develops as the lateral canthus drops in relation to the medial canthus, said Dr. Chesnut, who is in private practice in Spokane, Wash.
Courtesy Dr. Cameron Chesnut
Before canthopexy.
In the canthopexy, the lateral canthal tendon is folded over and stabilized with a stitch, but not dispensed with. “Yes, this is surgical, but this is literally a stab incision with an 11 blade to access this,” he noted.
The key to a successful canthopexy is to release the tarsal strap, which is relatively resistant to aging laxity and tethers the lateral canthus inferiorly. “While everything else around it becomes lax, it tends to stay pretty strong and pulls down the whole lateral canthal complex,” he observed.
The canthoplasty creates more tension on the lower lid, but is more invasive. The lateral canthal tendon is cut, releasing the retinaculum. The eyelid opening is then shortened and the tendon reconstructed and reattached to the bone.
Courtesy Dr. Cameron Chesnut
After the procedure, showing the benefits of lower lid support from canthopexy.
Particular attention should be paid in both procedures to globe position, particularly in patients with a negative vector in which the globe protrudes beyond their malar eminence and lower eyelid, Dr. Chesnut pointed out.
“You need to be careful with these patients because if you tighten the lower lid too much, the lower lid margin will take the path of least resistance and descend down the globe instead of up,” he said. “These are the patients that may need volume or face lifting to increase that malar support.” Complications can include overtightening, but this is nearly impossible to do with a canthopexy and usually relaxes with a canthoplasty, Dr. Chesnut said in an interview. “Avoiding it all boils down to proper preoperative planning of the amount of tightening needed.”
Likewise, proper planning can avoid undercorrection.
“This can occasionally be from failure of the reconstructed or plicated lateral canthal tendon, but this is a very robust structure, and when properly fixated to the periosteum of Whitnall’s tubercle, failure is unlikely,” Dr. Chesnut explained. “The tendon will continue to age normally, so a canthopexy patient may require or want more tightening with a canthoplasty years down the road.”
Lower-lid laxity should be assessed in all patients prior to either procedure and can be determined by performing the distraction test, in which the eyelid is grasped and pulled anteriorly. If the eyelid can be distracted by more than 6 mm to 8 mm, then laxity is present. The snapback test, where the lower lid is pulled toward the inferior orbital rim and then released, can also be used to identify poor lid tone.
Dr. Chesnut reported having no conflicts of interest.