Other techniques have been described for reattachment of the MCT to the orbital medial wall. Okazaki et al. This technique uses a screw hole that is drilled into the orbital medial wall, and a suture is threaded into the head of the anchoring device to push the anchor into the hole directly. The sutures are then sewn to the stump of the medial canthal tendon for fixation onto the bone. The self-tapping screw is able to create holes for fixation and the bone fixation point can be corrected if needed.
Turgot et al [17] described utilization of a unitransnasal canthoplasty to repair the MCT. This technique creates 2 drill holes in the periosteum matching the MCT attachment point. Advantages to this technique is that it is relatively easy, cheap, does not injure the opposite nasal bone, and does not require additional equipment. However, this study only included two patients, though both patients who underwent this procedure had good surgical outcomes. Other methods propose that MCT reconstruction may not necessarily be needed if the canalicular system is repaired.
In cases of combined eyelid avulsion and canalicular injury, placement of a bi-canalicular Crawford stent without reconstruction of the MCT has been noted to create good tissue alignment and cosmetic outcome. Following repair of a canalicular laceration, the stent is kept in for a minimum of six weeks, though can be left for longer months if it is not causing any issues or discomfort to the patient.
The stent can be removed from a nasal or ocular approach, depending on the stent used and if there was fixation such as to the nasal mucosa or through the inferior turbinate. After repair, the patient is typically given antibiotic ointment and possibly oral antibiotics if needed.
For post operative visits, patients are generally seen at week 1, week , with more long-term follow-up as needed. Patients can be expected to experience some mild bruising, swelling, and pain postoperatively and may have initial epistaxis. It is important to discuss possible complications with patients that can occur post surgical repair.
As with any ophthalmic procedure, there is risk of bleeding, infection, pain, or loss of vision. Other possible complications more specific to MCT repair include scarring due to poor healing, poor cosmetic outcomes, telecanthus, epiphora, ectropion, stenosis of the nasolacrimal system, or iatrogenic trauma to the undamaged canaliculus. Patients with postoperative complications may require additional surgery. In general, most patients who undergo prompt surgical repair of MCT avulsions have good functional and cosmetic outcomes.
Ophthalmic Plastic Surgery: Tricks of the Trade. Create account Log in. Main page. Getting Started. Recent changes. View form. View source. Jump to: navigation , search. Original article contributed by :. Karen M. Even in cases where a direct injury to the medial canthal tendon was discovered, instead of immediate repair of the canthal tendon, an epicanthoplasty during the follow-up period was planned, as immediate repair surgery could affect flap survival.
In medial canthal reconstruction, various techniques using a local flap such as rhomboid flap, subcutaneous pedicle V-Y advancement flap, upper eyelid myocutaneous flap from the ipsilateral or contralateral side, V-Y glabellar flap, forehead flap, and combinations of these flaps have been reported [ 2 ].
These procedures have advantages and disadvantages and are selected by surgeons according to the defect size, location, and donor site morbidity. Since the majority of the cases involve periosteum or bone exposure, difficulties with skin graft survival were expected, and even if the skin graft took well, a significant depression was expected with a poor cosmetic outcome.
In addition, most cases had partial upper and lower eyelid defects and skin grafting after an eyelid defect would limit opening and closing eye motion.
Taking into consideration these drawbacks of the skin graft, the flap surgery was the preferred procedure. V-Y-S plastic surgery was performed when the skin defect around the medial canthus was small. This had the advantage of a zigzag scar; however, this procedure cannot be applied when the defect is large [ 6 ].
Because this method uses the wrinkles of the glabella, the donor site scar after reconstruction remains in linear form. Therefore, the V-Y glabella flap is recommended as a good method. If the lesion size is large, it is possible to reconstruct the defect with the paramedian forehead flap method. The paramedian forehead flap method elevates the flap with the supratrochlear vessels and nerves. The supratrochlear artery rises from the supraorbital foramen toward the forehead under the periosteum.
After it runs to the eyebrow above the periosteum, it receives randomized vascularity at the infradermal layer. It is possible to design a flap in the desired shape from the center of the forehead after applying a linear incision line from the superior orbital rim to the forehead. A common method involves using the contralateral supratrochlear artery across the exact center of the nose to minimize torsion and obstruction of the pedicle by an acute rotation arc.
The drawback of this method is that the area between both sides of the medial canthus can bulge because of the pedicle running across the center of the nose.
The pedicle crossing the skin of the nose like a tube requires other operations, including flap division, after 3 weeks. In order to overcome this drawback, a method was devised in which the paramedian forehead flap is elevated at the ipsilateral forehead, the supratrochlear artery and vein are skeletonized by removing as much unnecessary subcutaneous tissue around the pedicle as possible, and the defect is covered by passing through a tunnel under the skin.
In many cases, the arteries of the face do not clearly accompany the vena comitans. The path of the supratrochlear artery can be confirmed using Doppler ultrasound; however, since the vein runs together with the artery in a separated state instead of as a clear vena comitans, it is difficult to completely skeletonize the artery and vein. If a mm width of the surrounding subcutaneous tissue is elevated, focusing on the artery path, the venous circulation will be included in it.
To remove the factors that compress the pedicle, a portion of subcutaneous tissue inside the subcutaneous tunnel, which is on the path to the medial canthus defect, was excised. The flap will not have venous congestion when the flap is naturally located on the defect; therefore, we provided sufficient distance so that the flap would not receive tension.
The medial canthus is closely attached to the medial canthal ligament, and it has a slightly pressed shape at the side of the nose. However, the forehead flap is thick; therefore, if the forehead flap would be simply sutured to the defect in the medial canthus, it would be thicker than the outside eyelid, and the mobility of the upper and lower eyelids would be impaired.
As a solution to this, the distal part of the flap to be located at the medial canthus was made thin by removing the subcutaneous fat, and the bottom of it was fixed at the medial canthal tendon.
In preparation for the possibility of the lid fissure becoming narrower due to scarring at a later time, the incision was created 2 mm longer than the lid fissure incision. Further, in order to prevent a union caused by scarring, the upper and lower eyelid conjunctiva were sutured to each split supraorbital and infraorbital rim of the flap. The suture line of the upper and lower eyelid and flap was oblique instead of vertical to prevent ectropion due to a vertical line scar.
The patients experienced no serious inconvenience in closing their eyes when the ratio of the flap to upper eyelid was ; however, if it was greater than that, the patients experienced epiphora because the lid fissure was always in an open state. When the flap was rotated while the pathway of the supratrochlear artery and vein was not clear, congestion was common; however, congestion could be alleviated by applying medicinal leeches.
When venous congestion occurred, stitches of a part of the thread suturing the flap were first removed to reduce the tension on the flap, and the congested flap was checked after 1 hour. In the 2 cases in which congestion occurred, no improvement was found in the post-intervention observation, and leech application was necessary.
To address venous congestion, Akan et al. A similar method involves laceration with a blade to induce continuous bleeding. Medicinal leech application is quite a good therapeutic approach when the congestion is temporary and the flap is not large [ 8 ]. In the case of a forehead flap, given the small flap size and low amount of bleeding required to relieve congestion, leech application is a very effective method.
Because of the position of the flap close to the eye, care was taken to prevent the leech from migrating from the flap toward the eyeball, which could result in injury to the eyeball. To prevent the leech from approaching the eyeball, tapes were attached to the upper and lower eyelids, which were kept closed, and the eyelids were then covered with gauze.
The leech application itself lasted from 15 to 30 minutes, and continuous bleeding after leech application was ensured by covering the bleeding point with heparin-soaked gauze. Nasal dorsum bulging caused by the pedicle crossing the nasal dorsum was not obvious during the early period of the operation, and the nose dorsum profile was able to retain its original shape. There was sensory loss at the forehead when a paramedian forehead flap method was used ipsilaterally or contralaterally; however, we sought the understanding of the patient by explaining the likelihood of this in advance.
We left subcutaneous tissue, including the periosteum, at the donor site defect and applied the full-thickness skin graft above it. When the flap is elevated, leaving much tissue at the forehead has the advantage of reducing flap thickness and donor site depression, but is likely to impede circulation in the flap.
Definition noun, plural: medial canthi The medial angle or corner of the eye where the upper and lower eyelids meet. Supplement The eye has two canthi, the medial canthus and the lateral canthus.
The medial canthus is that angle or corner of the eye situated medially or near the midplane of the face. Compare: lateral canthus See also: canthus. Upper canaliculus: epithelial-lined tube that carries tears from the punctum to the lacrimal sac. It is much less important than the lower canaliculus.
If severed or obstructed, tearing is unlikely to result because the lower canaliculus can absorb the overload. Medial canthus: the medial confluence of upper and lower eyelid margins. Lacrimal sac: collects tears coming from the canaliculi. Lacrimal gland: tucked under the upper outer orbital rim, the lacrimal gland provides tears during crying.
Basic wetting of the eye is handled by glands scattered throughout the conjunctiva. Lower punctum: oval opening in the lower lid margin where tears enter to flow to lacrimal sac. If the lower punctum is not well apposed to the conjunctiva, or becomes distorted or closed by inflammation or trauma, the patient will have a tearing problem. Lower canaliculus: epithelial-lined tube that carries tears from the punctum to the lacrimal sac.
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