Orbital Anthropometrics after Medial Canthopexy with Ipsilateral Titanium Microanchor Device
Dov C. Goldenberg, MD, MS, Endrigo O. Bastos, MD, Henri Friedhoffer, MD, PhD, Nivaldo Alonso, MD, PhD, Alexandre Fonseca, MD, and Marcus C. Ferreira, MD, PhD.
The medial canthal tendon is a complex anatomic structure originating from the pretarsal and preseptal portions of the orbicularis muscle. Its insertion on the medial orbital wall, on the lacrimal crest region, is divided in three portions. The anterior horizontal and vertical portions are of paramount importance for canthal positioning1.
Deformities of the medial canthus can de secondary to trauma, craniofacial deformitites, surgical procedures where its desinsertion is necessary or as a consequence of tumor resection2,3,4,5.
Management of medial canthal deformities still remains a great challenge in craniofacial surgery. Current techniques include transnasal and ipsilateral methods for positioning and fixation1,3. Techniques of transnasal canthoplasty and canthopexy present an elevated rate of relapse and malpositioning. Also, the risk of lesion to the contralateral orbit is considerable. Ipsilateral techniques used in the past did not show, as well, satisfactory results.
The aim of the present study was to evaluate an alternative method for repair of medial canthal tendon displacement, using a microanchor system (1.3mm Micro QuickAnchor®, Mitek® Products, Westwood, MA, USA) placed by an ispilateral approach.
Nine patients with medial canthal dystopia, secondary to trauma, tumor resection or congenital craniofacial deformities were treated with this approach. Seven deformities were unilateral and two were bilateral. Ages ranged from 11 to 46 years old (mean 25.22 years old). Five patients were male and 4 were female.
Technically, the microanchor system was of simple instrumentation. Adequate positioning of the hole for microanchor insertion, at the posterosuperior portion of the lacrimal crest was achieved in all cases. It allowed a good positioning of the medial canthus.
Pre-operative, immediate post-operative and 1 year follow-up anthopometrics of the orbital region were evaluated, including measurement of intercanthal distance (ICD) , medial canthus-midline distance (MCMD), lateral canthus-midline distance (LCMD) and orbital width (OW).
Immediately after surgery, an intended overcorrection was produced, reducing the anthropometrical measurements, when compared to the normal sides. During follow-up, a tendency of the medial canthus to assume and sustain a position similar to the normal sides was observed (Figure 1 and Table1).
Partial relapse is a problem faced by many authors in several series3. In the present study partial relapse occurred in two patients. However, stability of anchor positioning was found in all patients. Consequently, partial relapse of medial canthal positioning was probably due to stretching or breaking of the suture-tendon interface.
In conclusion, the use of michroanchor system for medial canthopexy can be considered an easy and effective option for treatment of medial canthal dystopia.
Patient / Age / Gender / Etiology / Affected side / MCMD right (mm) / MCMD left (mm)Pre / Immed / 1 year / Pre / Immed / 1 year
1 / 16 / Male / Trauma / Bilateral / 20 / 5 / 17 / 20 / 5 / 19
2 / 42 / Female / Trauma / Right / 22 / 14 / 17 / 17 / 17 / 16
3 / 24 / Male / Tumor / Right / 35 / 15 / 18 / 20 / 20 / 18
4 / 46 / Female / Trauma / Right / 22 / 12 / 14 / 18 / 17 / 18
5 / 12 / Male / Congenital / Right / 26 / 15 / 24 / 20 / 18 / 20
6 / 18 / Male / Trauma / Left / 18 / 18 / 16 / 28 / 16 / 24
7 / 18 / Female / Trauma / Right / 20 / 16 / 18 / 19 / 19 / 18
8 / 40 / Male / Trauma / Right / 22 / 16 / 19 / 18 / 18 / 19
9 / 11 / Female / Congenital / Billateral / 18 / 16 / 16 / 19 / 17 / 18
Table 1. Patient data and medial canthal-midline distance (MCMD) measurements in the normal and affected sides.
References
1. Zide, BM; McCarthy, JG. The medial canthus revisited – an anatomical basis for canthopexy; Ann Plast Surg 11; 1-9; 1983
2. Antonyshin, OM. Wienberg, MJ; Dagum, AB. Use of a new anchoring device for tendon reinsertion in medial canthopexy; Plast Reconstr Surg 98; 520-3, 1996
3. Calahan, A; Calahan, MA. Fixation of the medial cantal structures: evolution of the best method. Ann Plast Surg 11; 242-5; 1983
4. Dagum, AB; Antonyshin, OM; Hearn, T. Medial canthopexy: an experimental and biomechanical study. Ann Plast Surg 35; 262-5; 1995
5. Okazaki, M; Akizuki, M; Ohmori, K. Medial canthoplasty with Mitek Anchor System. Ann Plast Surg 38; 124-8; 1997