CASO CLÍNICO

 

Transconjunctival, transcaruncular approach: enlarged orbital medial wall exposure. An alternative to the coronal approach

Abordaje transconjuntival más transcaruncular: amplia exposición de la pared medial orbitaria. Una alternativa al abordaje coronal

 

 

J. Rodríguez¹, R Galán¹, X. Valldeperas², M. Mateos¹, G. Forteza³

1 Médico Adjunto.
2 Médico Residente.
3 Jefe de Servicio.
Servicio Cirugía Oral y Maxilofacial. Hospital Joan XXIII. Tarragona, España

Correspondence

 

 

---

ABSTRACT

Prominent nasolabial folds are of concern to many face lift candidates. Many techniques have been described which tackle this distinct sign of ageing. Crease fillers have inherent limitations. Extended SMAS dissection and suspension has no effect after 24 hours. Malar fat pad suspension has an effect which extends maximally to 2 years. Direct fat excision lateral to the crease must be done cautiously. However, it is the only technique providing permanent results. Fat removal can be done with tweezers and scissors, with liposuction canules, and with curettes. Tactile and visual control over location and depth of the resection is required. Such is possible when using a bone rongeur in one hand to reduce the fat mount which has been dissected off the dermis. The other hand turns over the cheek flap for alternating internal and external control of the sculpturing effect, and for external tactile guidance.

Key words: Rhytidoplasty; Rejuvenation; Surgical Instruments, Utilization.

---

RESUMEN

Los pliegues nasolabiales prominentes son uno de los aspectos que más preocupan a los pacientes candidatos a un lifting facial, y han sido descritas muchas técnicas que intentan atenuar este signo distintivo del envejecimiento. Las sustancias de relleno tienen limitaciones inherentes. Las disecciones amplias del SMAS y su posterior suspensión no tienen efecto después de transcurridas 24 horas. La suspensión de la almohadilla grasa malar tiene un efecto que se extiende como máximo a los dos años de duración. La extirpación directa de la grasa lateralmente al surco nasolabial, aunque debe hacerse con mucha cautela, es la única técnica que proporciona resultados permanentes. Técnicamente, esta resección grasa se ha descrito realizada valiéndose de pinzas y tijeras, con cánulas de liposucción o con curetas. Este procedimiento requiere un control muy preciso, táctil y visual, de la localización y profundidad de la extirpación, control que puede mejorarse usando una gubia ósea con una mano para extirpar la grasa a eliminar de la dermis, mientras la otra mano maneja el colgajo cutáneo de la mejilla, para un control alternativo interno y externo del efecto escultural de la extirpación y para permitir una guía táctil externa.

Palabras clave: Ritidoplastia; Rejuvenecimiento; Instrumentos quirúrgicos; Utilización.

---

 

Introduction

The orbital medial wall is injured relatively often in orbital trauma and this fact often is minimized in reconstruction or repair due to its complexity. The medial wall supports the lacrimal tract and is perforated by the anterior and posterior ethmoidal arteries. The inferior oblique extraocular muscle inserts on the medial wall and the trochlea of the superior oblique muscle is found in the upper angle. This approach also offers excellent surgical field for the orbital apex and sphenoidal sinus.

The first orbital approach was used to access the frontal sinus, ethmoidal air cells, and sphenoidal sinus and was described by Bergh in 1886. Lynch¹ made the incision between the internal canthus and the glabellar region. The transorbital approach used for orbital decompression in Graves disease, which was described by McCord² and Anderson and Lindberg,³ requires extensive dissection of the lower conjunctival fornix and external canthal ligament, in addition to skin incisions. More recently, Kennedy⁴ described an endoscopic approach for treating this thyroid ophthalmoplegia and optic nerve compression.^5,7 These approaches do not produce scars, but the operating time is prolonged and the surgeon’s maneuverability is frankly constrained. These approaches are suitable only for decompression procedures, resection of small tumors, or drainage of ethmoidal sinus abscesses.

In this article we propose a new approach that combines a transconjunctival and transcaruncular incision and describe the anatomic relations of the internal canthal region by planes.

However, in the case of high energy trauma of the middle third or trauma of the upper third, this technique is a complementary procedure for enhancing exposure and cannot replace the classic approaches.

The transcaruncular approach has been described in the literature, mainly in ophthalmologic journals, for the repair of fractures of the orbital medial wall⁸ and internal canthal ligament,^9,10 as well as for lacrimal tract repair.¹¹

We do not propose to examine the transconjunctival approach in depth in this short paper, but we will discuss certain particulars of the procedure.

The aim of this article was to propose an alternative to the coronal approach that consists of an enlarged transconjunctival approach to expose the orbital medial wall. This option had minimal morbidity and can economize on surgical time.

 

Anatomy Surgical

The tendon of the internal canthus has an anterior fibrous part and a posterior fibromuscular part (Fig. 1). The fibrous part inserts on the anterior lacrimal crest and the fibromuscular part on the posterior lacrimal crest. The lacrimal sac lies between these two parts. The tendon divides into superior and inferior sections for the insertion of the tarsal plate and the superior and inferior orbicularis oculi ligaments.

The preseptal and pretarsal orbicularis oculi muscles insert on the anterior tendon. These insertions are fibrous. The posterior portion of the internal canthus, which is more muscular, is the continuation of the deep fibers of the pretarsal and preseptal orbicularis oculi muscle. This fibromuscular specialization, or pars lacrimalis, is called the Horner muscle. When this muscle contracts, it draws the internal canthus in medial direction and has the effect of pumping the tears through the lacrimonasal duct. However, tears drain mainly by gravity.¹³

The lacrimal canaliculi lie between the anterior fibrous and posterior bundles of the pretarsal orbicularis oculi muscle.

There may be some variability in the individual muscular insertions of the pars lacrimales, but this is not particularly relevant to surgical practice.¹²

The inferior oblique extraocular muscle has its anatomic point of insertion behind the equator of the ocular globe, in the inferoexternal quadrant near the inferior rectus muscle. Its other end inserts on the orbital medial wall, on a small elevation located behind the entry orifice of the nasolacrimal duct, as shown in figure 4. As a result of this anatomic disposition, the main action of this muscle during contraction is the elevation, abduction, and extorsion of the eyeball.

 

Surgical technique

The inferior conjunctival incision should be made as low as possible without infringing on the capsulopalpebral fascia. Dissection continues anteriorly to the inferior orbital septum to the lower orbital rim. An incision is made in the periorbita two or three millimeters behind the rim. This transconjunctival incision continues medially and upward with the transcaruncular incision between the conjunctival medial fornix and plica semilunaris, thus separating the incision in the inferiomedial angle from the inferior canaliculus. At this point, a suture is placed between the conjunctiva and the upper eyelid to protect the cornea, or corneal protectors are used. The lacrimal caruncle is separated medially using a Desmarres separator and the conjunctival incision runs from the inferior fornix to the medial fornix. This maneuver can be performed with Stevens scissors. The medial region is dissected between the orbital septum and the posterior arm of the medial canthal ligament—more exactly, Horner’s muscle. This lacrimal secretory muscle inserts on the periorbita of the posterior lacrimal crest. A Freer type elevator is used to probe the posterior lacrimal crest (Fig. 2). By blunt dissection of the posterior lacrimal crest, this muscle- ligament-gland complex is separated from the septum, medial rectus muscle, and eyeball, which is separated laterally. Dissection continues medially to the lacrimal crest, but not posteriorly because this may injure the medial rectus muscle. The periorbita is incised at the level of the posterior lacrimal crest and the periosteum is lifted from the medial wall. (Fig. 3)

The lower limit of the transcaruncular dissection is the inferior oblique muscle. This muscle is also the medial limit of the transconjunctival dissection (Fig. 4). Once the muscle is identified, it is disinserted from its origin and marked with a suture for later resuturing. When we have freed the inferior oblique muscle, the surgical field is notably larger because we can now anteriorly retract all the palpebral structures together with the lacrimal tract without risk of injuring the lacrimal canaliculi (Fig. 5).

The periorbita is closed with resorbable material. The transconjunctival incision is not sutured if it was made in the fornix.

 

Discussion

The traditional transconjunctival approach can be enlarged laterally with lateral canthotomy and a relaxed skin tension line. The transcaruncular approach gives us a clear field in the internal canthal region. The main drawback of the transcaruncular approach is that it offers a limited field for working on the medial wall, suitable only for small bone grafts not exceeding 15 x 20 millimeters.

Disinsertion of the inferior oblique muscle joins the inferior and medial approaches, giving the surgeon a large surgical field of vision of the medial orbital wall. It is important to lift the periosteum together with the muscular insertion to facilitate resuture (Fig. 5). This maneuver should be performed when a large exposure of the medial wall is needed.

The use of a spatial plane as a reference for fracture reduction is familiar to maxillofacial surgeons, principally in the treatment of orbital and zygomatic fractures. In these cases the lateral wall of the orbit helps to guide malar reduction. By visualizing the medial wall, we can evaluate the sagittal alignment of centrofacial fracture reductions, both Le Fort and nasoethmoidal fractures, as long as there is no major comminution of the fragments. Osteosynthesis of the medial wall obviously is contraindicated, but we can sometimes perform direct fixation of this orbital lateral wall with a miniplate.

This approach provides an ample exposure for hemostasis of the ethmoidal arteries. This route allows better correction of the inferomedial strut of the orbit than the transconjunctival approach, which is a key point in the reconstruction of the orbital floor and medial wall in severe trauma.

We can directly repair the internal canthal tendon and, better yet, the posterior part of the internal canthus, the minimizing the need for translacrimal canthopexy.

Clinical case

An 18-year-old patient was seen for central facial trauma due to a traffic accident. The patient had Le Fort type II, right nasoethmoidal type II, and left type I fractures that produced an open anterior bite, hypertelorism, and bilateral orbital ecchymoses. After splinting both dental arches, the maxilla was reduced and the jaw was locked. The fractures were exposed bilaterally via inferior approaches. Good stabilization of the jaw and nasoethmoidal fracture was achieved on the left side. A transconjunctival incision was made on the right side and enlarged with a transcaruncular incision. Both approaches were joined after disinsertion of the inferior oblique muscle. The fragments were reduced by verifying the reduction plane on the medial wall. Osteosynthesis was done with microplates on the infraorbital rim. We packed the medial wall with 20 mm x 25 mm PDS grafts until the volume was adequately restituted. The periosteum was sutured with vicryl 5/0 and a 13 mm needle and the inferior oblique muscle was reinserted. The transconjunctival approach was not closed. The patient did not present diplopia or any deficit or overactivity of the inferior oblique or other extraocular muscles in the ophthalmologic followup visits at one week and two months of the intervention. (Fig. 6)

 

Conclusions

The approach to the orbital medial wall has always been a challenge for craniofacial surgeons. Until now, a coronal approach had to be performed as none offered sufficient exposure. Using the transconjunctival approach, when we have wanted to dissect more medially, we could do so by tunneling behind the oblique muscle, often without knowing its exact location.

We proposed in this article to describe this approach in detail, which can sometimes avoid the need for a coronal incision. However, a coronal incision can never be ruled out in high energy trauma or in trauma to the upper third of the orbital medial wall.

 

 

Correspondence:
Dr. Javier Rordíguez Fernández
Hospital Universitari de Tarragona Joan XXIII
Servicio de Cirugía Oral y Maxilofacial
Carrer del Doctor Mallafrè Guasch 4
43007 Tarragona, España
e-mail: javier.doctork@gmail.com

Recibido: 09.05.2007
Aceptado: 16.06.2008

 

References

1. Lynch RC. The technique of a radical frontal sinus operation which has given me the best results. Laryngoscope 1921;31:1-5.        [ Links ]

2. McCord CD. Orbital decompression for Graves’ disease expo-sure through lateral canthal and inferior fornix incision. Ophthalmology 1981;88:533-41.        [ Links ]

3. Anderson RL, Lindberg JV. Transorbital approach to decom-pression in Graves’ disease. Arch Ophthalmol 1981;99:120-124. Mosby, Inc., 2001:405        [ Links ]

4. Kennedy DW, Goodstein ML, Miller NR, y cols. Endoscopic transnasal orbital decompression. Arch Otolaryngol Head Neck Surg 1990;116:275-82.        [ Links ]

5. Graham SM, Carter KD. Combined-approach orbital decom-pression for thyroid-related orbitopathy. Clin Otolaryngol 1999;24:109-13.        [ Links ]

6. Manning SC. Endoscopic management of medial subperiosteal orbital access. Arch Otolaryngol Head Neck Surg 1993;119:789-91.        [ Links ]

7. Shorr N, Baylis HI, Goldberg RA, y cols. Transcaruncular approach to the medial orbit and apex. Ophthalmology 2000;107:1459-63.        [ Links ]

8. Graham SM. The transcaruncular approach to the medial orbital wall. Laryngoscope 2002;112:986-9.        [ Links ]

9. Francis IC. Transcaruncular medial orbitotomyfor stabilization of thet posterior limb of the medial canthal tendon. Clin Experiment Ophthalmol 2001;29:85-9.        [ Links ]

10. Fante RG. Transcaruncular approach to the medial canthal tendon plication for lower eyelid laxity. Ophthal Plast Reconstr Surg 2001;17:16-27.        [ Links ]

11. Lee JS. The treatment of the lacrimal apparatus obstruction with the use of a inner canthal Jones tubeinsertion via a transcaruncular approach. Ophthalmic Surg Lasers 2001;32:48-54.        [ Links ]

12. Tyers AG. Colour Atlas of Ophtalmic Plastic Surgery, Curchill Livingstone 1995;pp 7-8.        [ Links ]

13. Warwik R. Eugene Wolff´s anatomy of the eye and orbit. 7 ed H K Lewis, London 1976.        [ Links ]

14. Testut L. Tratado de anatomía topográfica con aplicaciones medico-quirúrgicas. 4 ed, Salvat Ed, Barcelona 1926;1.        [ Links ]