ORIGINAL ARTICLE The Precaruncular Approach to the Medial Orbit Kris. S. Moe, MD Background: Most approaches to the medial orbit and bit, with a clear, avascular path of dissection and im- lower provide suboptimal access and leave visible scars. proved exposure. In 15 consecutive procedures, there were The transcaruncular approach is an improvement over no complications. The patients healed rapidly, with mini- previous procedures, but disadvantages remain: there is mal postoperative morbidity. no defined surgical plane through the caruncle; the ca- runcular tissue is highly vascular; and the approach may Conclusions: The precaruncular approach was demon- cause considerable postoperative morbidity. For these rea- strated on cadavers to be more efficacious than ap- sons, cadavers were studied to develop a surgical ap- proaches directly through or lateral to the caruncle. This proach that would avoid the caruncle. A prospective out- finding was confirmed in a prospective evaluation of 15 come evaluation was then performed. procedures, in which no complications occurred. More rapid healing was noted than with prior experience us- Materials and Methods: Two male and 2 female ca- ing the transcaruncular route. The precaruncular ap- davers were studied to ascertain whether the plane me- proach provides a preseptal plane to the medial orbit that dial or lateral to the caruncle provided optimal access to can be extended to the orbital floor or roof as needed, the medial orbit. Fifteen consecutive procedures were then and offers a direct connection between the posterior lac- prospectively evaluated using the medial approach. rimal crest and the tarsal plate for medial canthopexy. Results: The “precaruncular” approach medial to the caruncle provided the most direct route to the medial or- Arch Facial Plast Surg. 2003;5:483-487 URGICAL ACCESS to the me- be extended into a transconjunctival ap- dial orbit is necessary to treat proach that reaches the orbit floor and/or a diverse range of patho- roof as well. logic conditions, including In 1999, I began using this approach neoplasia, infection, trauma, for medial canthopexy. As with the lateral Sand malposition or laxity of the medial can- canthal tendon, correction of laxity of the thal tendon. The majority of surgical ap- medial canthus requires tightening of the proaches in use today, such as the Lynch tendon in all 3 vectors (horizontal, verti- incision, are transcutaneous and thus cre- cal, and especially anteroposterior). This ate scars. In addition to the cosmetic dis- can only be accomplished using a advantage of this location, incisions placed posterior-superior approach with tighten- between the medial canthus and the na- ing of the posterior limb of the tendon sal dorsum are prone to scarring and web (Figure 2). This procedure was found formation.1,2 Furthermore, incisions in this to provide a distinct advantage over the area may provide poor surgical access, par- standard techniques of canthopexy that ticularly during correction of laxity of the tighten only the anterior limb of the ten- medial canthal tendon. don and thus address only the horizontal The transcaruncular approach has re- and perhaps vertical vectors. The first 3 cently been gaining popularity for access cases in which this was attempted pro- 3 From the Department of to the medial orbit. Because the incision vided the desired surgical correction but Surgery, Division of is made through the conjunctiva and car- caused prolonged edema, erythema, and Otolaryngology–Head and uncle (Figure 1), no cutaneous scars are irritation in the caruncle, which lasted up Neck Surgery, University of formed. The exposure provided is also ex- to several weeks. Delayed healing has California, San Diego. cellent and allows ample access that may also been noted by Fante and Elner,4 who (REPRINTED) ARCH FACIAL PLAST SURG/ VOL 5, NOV/ DEC 2003 WWW.ARCHFACIAL.COM 483 ©2003 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/30/2021 Lacrimal Canal Edge of Conjunctiva Anterior Limb of Medial Canthal Tendon Plica Semilunaris Edge of Skin Lacrimal Sac Lacrimal Caruncle Posterior Lacrimal Crest Anterior Lacrimal Crest Posterior-Inferior Limb of Medial Tarsal Plate Canthal Tendon (Horner Muscle) Figure 1. Medial aspect of the right eye, oblique view. The lacrimal caruncle Figure 2. Anatomy of the medial canthal tendon. The anterior and posterior and plica semilunaris are illustrated, along with the position of the tarsal limbs of the medial canthal tendon are illustrated, with the caruncle and plate and the superior and inferior lacrimal puncta. adjacent conjunctiva reflected laterally. The lacrimal canaliculi are shown entering into the lacrimal sac (medial to the canthal tendon). found that the edema persisted more than 2 months in some of their patients who underwent a transcaruncular dissecting behind Horner’s muscle and can protect the approach. Furthermore, there is no defined surgical lacrimal canaliculi and retract the eyelids by keeping the plane within the caruncle; landmarks for dissection lacrimal probes in place during the procedure. The ques- within the structure are lacking; and the tissue is quite tion thus becomes whether the preseptal plane behind vascular. For these reasons, I decided to investigate the Horner’s muscle should be entered medial or lateral to possibility of an alternative approach, avoiding incisions the caruncle. in the caruncle, with the purpose of developing an approach with improved landmarks and diminished METHODS postoperative edema. A cadaver study was planned to explore other options, and a prospective evaluation of ANATOMICAL CADAVER STUDY the results was undertaken. In designing a surgical approach to the medial or- Four fresh cadaver heads, 2 male and 2 female, were inspected to ensure that there were no visible abnormalities of the upper bit, the goal should be to encounter the posterior lacri- or lower eyelids. On each side (N=8), the following proce- mal crest (Figure 2). Approaching bone anterior to this dure was performed. Size 4-0 lacrimal probes were placed structure places the posterior limb of the medial canthal through the upper and lower canaliculi into the lacrimal sac tendon as well as the lacrimal sac at risk of injury. Ap- and used for retraction of the upper and lower eyelids. To evalu- proaching the orbital wall posterior to the posterior crest ate the proposed lateral approach, an incision was made with is suboptimal because of crowding of the orbital con- a No. 11 blade immediately lateral to the lacrimal caruncle tents, and this type of approach may cause damage to through the conjunctiva of the plica semilunaris (Figure 1). A structures of the medial orbit, such as the medial rectus Wescott scissors was used to dissect along the lateral aspect of muscle. Furthermore, a more posteror approach will fail the caruncle inferiorly until Horner’s muscle was encoun- to raise the periosteum of the anterior lamina papyra- tered. Horner’s muscle was then followed medially to its in- sertion on the posterior lacrimal crest. The periosteum of the cea, where fractures may be located. The most expedi- medial orbit was then incised and elevated off the lamina papy- tious guide to this area is Horner’s muscle (the posterior- racea to expose the medial wall. inferior limb of the medial canthal tendon), which can To evaluate the medial approach, a No. 11 blade was used be followed medially to its insertion on the posterior lac- to make an incision medial to the caruncle at the border of the rimal crest. By approaching immediately posterior to Hor- medial canthal skin. The incision was continued toward the in- ner’s muscle, the dissection is performed in the presep- ferior and superior aspects of the plica semilunaris. Horner’s tal plane, which prevents herniation of the orbital fat muscle was identified immediately medial and deep to the con- during the procedure and allows a direct avascular path junctiva at the medial apex and inferior limb of the incision, to the orbit floor, should extended access be required. and a preseptal plane was developed posterior to the muscle At the medial aspect of the posterior limb of the canthal by spreading the tips of the scissors. Horner’s muscle was then followed to its insertion on the posterior lacrimal crest, leav- tendon, the septal tissue is a continuation of the supe- ing the tissue isolated between the medial and lateral ap- rior orbital septum, where it inserts on the posterior lac- proaches attached to bone. The surgical exposure of the area rimal crest, while more laterally the septum originates of the posterior lacrimal crest and lamina papyracea was then on the inferior orbital rim and inserts on the anterior lac- compared by viewing medial and lateral to the caruncle and rimal crest. The surgeon can protect the lacrimal sac by associated soft tissue. (REPRINTED) ARCH FACIAL PLAST SURG/ VOL 5, NOV/ DEC 2003 WWW.ARCHFACIAL.COM 484 ©2003 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/30/2021 Table 1. Ectropion Grading Scale Grade Description 0 Normal eyelid appearance and function I Normal appearance but symptomatic; laxity present on examination Lacrimal Probe II Sclerae show without eversion of eyelid Caruncle III Ectropion without eversion of inferior lacrimal punctum Conjunctival Incision IV Advanced ectropion with eversion of punctum from lacrimal lake V Ectropion with complication (eg, conjunctival metaplasia, retraction of anterior lamella, or stenosis of lacrimal system) L Predominantly lateral M Predominantly medial Incision for r Previous surgical revision (number of prior corrections may Canthal Tightening be indicated by the addition of a number after the r, eg, L III/M Ir2) Incision for Orbital Floor Extension PROSPECTIVE OUTCOME EVALUATION Figure 3. Conjunctival incisions for the precaruncular approach. Lacrimal The following data were collected prospectively on 15 consecu- probes are placed in the superior and inferior lacrimal puncta.