A prolapse of orbital fat in the lower eyelid is the most frequent reason for patients to ask for a lower bleph. Only in very rare cases a resection of skin is necessary and that's why in the lower eyelid I prefer a transconjunctival instead of a transcutaneous approach. Besides, in transconjunctival blephs there is no visible scar, so: no sutures have to be placed (or removed!) and the orbicularis muscle does be incised. For this reason the risk for postoperative ectropium and/or scleral show is only minimal. Indeed: not only excessive skin resection can cause ectropium. Even a simple incision in the orbicularis muscle or orbital septum alone can cause retraction and postop ectropium or scleral show! On the other hand an incision in the highly vascularised tarsal conjunctiva can give a significant bleeding, especially in patients with a short lower eyelid and undeep cul de sac where the fat pockets ore not easily accessible. My technique of transconjunctival blephs of the lower eyelid tries to deal with all these aspects.
Anaesthesia: When doing surgery under local anaesthesia we start with a deep subcutaneous injection of Xylocaïne 2% with epinephrine. Then the lower eyelid is everted using a Desmarres retractor and subsequently Xylocaïne 2% with epinephrine is injected subconjunctivally. The purpose of this subconjunctival injection is quadriple: - Additional anaesthesia. - Vasoconstriction thanks to the epinephrin. - Hydrodissection of the conjunctiva and retractor muscles. - Wetting of the tissues with the injection of anaesthetique facilitates the radiosurgical incision. That is why, also in patients under general anaesthesia I always inject Xylocaïne 2% with epinephrin subconjunctivally.
Although theoretically surgery can be performed both under local and general anaesthesia, I prefer the latter: the transconjunctival incision appears to be more stressy for a lot of patients. This can induce the blood pressure to rise thus causing more bleeding. An intervention under general anaesthesia therefor is not only safer bus also more comfortable for both surgeon and patient! Besides, in accordance with the anaesthesiologist blood pressure can be lowered maximally during general anaesthesia.
Surgical technique: The lower lid is everted wit a Desmarres lid retractor. Additional Xylocaïne 2% with epinephrine is injected subconjunctivally and as superficial as possible. Thanks to both stretching of the lower eyelid with the lid retractor and the effect of the epinephrin an almost bloodless area is created to further diminish the bleeding during the intervention. The stretching of the lid also facilitates the incision of the lid layer per layer. Tips for the Radiosurgeon: for the radiosurgical incision in de conjunctiva I use a relatively thick electrode with the unit in the cut/coagulate mode which gives 50% cutting and 50% coagulation. The thicker electrode than the one that is used for skin incisions gives an extra coagulation so that the incision almost doesn't bleed at all. If vessels or bleeders are seen, they can be grasped with a forceps and coagulated by touching the forceps with the electrode and activating the unit shortly. The incision: The incision in the conjunctiva is very superficial, parallel to the lower tarsal border but a few milimeters lower. The cut conjunctiva is lifted with the forceps and then a similar incision is made through the retractor muscles and subsequently the orbital septum. The lid retractor is then removed. Removal of the fat: By pushing slightly on the globe, the fat now will prolapse. Because the septum is a multilayered structure, sometimes additional membranes need to be cut before the fat pockets pop out of the orbit. For maximal dilation of the wound, a wound hook with blunt edges on the cranial side and a forceps in the caudal side is used. With the unit in the cut/coagulate mode direct resection of the fat without the use of a clamp is possible. It's important to cut very slowly to have a maximal coagulation effect. Thicker blood vessels, when encountered, can be coagulated before cutting, in the same way as described for the conjunctival incision. We have to be careful to excise only pure fat. Indeed: the inferior oblique muscle lies between the nasal and central fat pocket and must not be harmed! Fat resection has to be very conservative: the pockets in the lower eyelid are not caused by excess of fat but only by a prolapsing of the anatomical fat pockets. Besides: the quantity of orbital fat diminishes with age and we have to take care not to cause a ‘sunken' eye! We are searching for an ideal technique to dissect the fat without bleeding an to re-position it and fixate it, without any need to excise fat. Final steps: At the end of the intervention we check the wound for eventual bleeders. With a forceps the lid is pulled upwards to loosen eventual adhesions. I do not suture the conjunctiva at all but only put some antibiotic ointment. Tranexamin is administered intervenously and a cooling compress is put on the eye. Posoperative checks: An ambulatory check up is done after 6 days. At this moment it is not unusual to notice some conjunctival oedema. The skin can be moderately wrinkled. If wrinkles persist, a superficial peeling can be performed after a month. Only in very rare cases a (conservative) excision of skin is needed. This can be combined with a suspension of the orbicularis muscle to the periostium of the temporal superior border of the orbit.
--------
Peter Raus MD is the head of Miró, a centre for Ophthalmology, Oculoplastic Surgery and Aesthetic Medicine of the face. Peter was trained in Belgium, Spain, Egypt and the USA
http://www.dry-eyes-therapy.com
