www.ivis.org Proceedings of the Southern European Veterinary Conference and Congreso Nacional de AVEPA Oct. 18-21, 2012 - Barcelona, Spain Next Conference: Oct. 17-19, 2013 - Barcelona, Spain Reprinted in the IVIS website with the permission of the SEVC - AVEPA
BASIC EYELID SURGERY Christine L Heinrich DVOphthal DipECVO MRCVS Willows Referral Service, Highlands Road, Solihull, B90 4NH, UK MAGNIFICATION AND ILLUMINATION Ideally, eyelid surgery should be carried out with the help of magnification. Binocular head loupes are available in a wide range of magnification factors but for most eyelid procedures, a 2.5 3.5x magnification is adequate. Illumination with binocular loupes may be from a bright overhead operating light. INSTRUMENTS The selection of instruments is very much a case of personal preference. In general, instruments for ophthalmic surgery should be dedicated solely to this purpose, as their incorrect use on other tissues will damage them. The following are some suggestions for a basic kit for eyelid surgery: Strong straight scissors with rounded tips Scalpel handle and No15 Swann Morton blade Fine rat-tooth forceps (e.g. St Martins forceps) to handle skin and conjunctiva Steven s tenotomy scissors for skin and conjunctiva Microsurgical needle holders without a catch (e.g. Castroviejo s) for handling 6/0 suture material 2-3 pairs of fine hemostats SUTURE MATERIALS The author uses almost exclusively 6/0 coated polyglactin 910 (Vicryl or Vicryl Rapide, Ethicon Inc, US) on a reverse cutting 3/8 11mm needle for eyelid skin closure. The use of non-absorbable suture material may of course cause less skin reaction but has significant disadvantages one being, that it can be very difficult to remove eyelid sutures from conscious canine patients and secondly, that their generally more rigid knots and suture ends (if compared to Vicryl ) will cause more damage if they inadvertently come into contact with the corneal surface. PATIENT PREPARATION Most patients are treated pre-operatively with an NSAID (e.g. carprofen or meloxicam) to minimize intra- and post-operative wound swelling. The use of peri-operative systemic antibiotics may be indicated in some patients. Anesthesia for eyelid surgery is usually routine. After induction, KY-Jelly is placed into the conjunctival sac whilst the hair is clipped. For patients with concurrent corneal wounds (non-penetrating) sterile KY-Jelly in sachets can be used. Lashes are trimmed with scissors coated in KY-Jelly to collect the hairs immediately. Care is taken to
minimally traumatize the periocular skin with clipping to reduce the risk of inducing clipper-rash which could lead the patient to self-traumatize the surgical area. In some breeds, it is preferable not to aim for a close clip, as this would cause excessive skin damage such as in the Boxer, the Cocker Spaniel or the Shar Pei. The clipped hair can be removed from the periocular area with a combination of careful use of a vacuum cleaner and a sticky roller designed to remove hair from clothes. Sellotape can also be used to remove minor remaining hair clippings. For the eyelid surgeries described below, the patient is placed in lateral recumbency and the head is elevated and brought in a horizontal position with the help of a deflatable vacuum bag ( buster bag ). The ocular surface, conjunctival sacs and eyelids are prepared in a way that is not damaging to the corneal surface. A dilute Povidone-iodine solution (1/50) is used; when preparing this it is of utmost importance that Povidone stock solution is chosen and not the scrub (the latter contains detergents that are toxic to the corneal epithelium The eye and conjunctival fornices are initially gently wiped clean with a sterile cotton-tipped applicator to remove the KY-Jelly. The eye is then flushed 3-5 times with 10 ml; care is taken to flush behind the third eyelid and into the conjunctival fornices. In order to facilitate the flushing, a soft/plastic naso-lacrimal cannula can be applied to the syringe containing the flushing solution. The periocular skin is gently wiped 3-5x for both upper and lower lid with the 1/50 dilution. Preparation of the eye for surgery is completed with a final flush with sterile saline. For surgery, the eye is draped with a sterile surgical cloth that has an adequate window. Both the use of re-usable drapes and of single use drapes is possible. SIMPLE EYELID DEFECT REPAIR Fig. 1
This technique (Fig.1) is applied after the removal of eyelid tumors or after eyelid trauma (e.g. dog fight). In the case of a tumor excision, the wedge of skin to be removed is outlined with a No15 Bard-Parker scalpel blade to near conjunctival depth. A gloved finger is inserted into the conjunctival fornix for this purpose to stretch and stabilize the skin during incision. Care is taken to make both incisions perpendicular to the eyelid margin and ideally; the parallel incisions are connected to leave a defect in the shape of a small house. The wedge of skin is then excised using blunt tenotomy scissors. The use of scissors without outlining the defect first with a scalpel blade is poor technique and will result in an uneven cut into the eyelid margin which in turn will complicate closure of the defect later. Approximately 1/3 rd of the total eyelid length can be excised to still leave enough lid behind to allow direct closure of the defect. In some breeds with long eyelids (such as the Cocker Spaniel), even up to ½ of the total eyelid length may be resected. If a tumor is larger and requires more extensive lid tissue resection, alternative surgical approaches for a more complex restoration of the eyelid margin have to be considered. When repairing the lid margin, it is important that the suture material does not contact the cornea. The first suture to be placed is the one nearest the lid margin. A figure 8 pattern is used, starting in skin, emerging at the level of the meibomian gland orifices, crossing the wound margin and following the same track in reverse on the other side of the wound. It is essential that the distances between the different suture-parts are equal, as this will create a secure and accurate repair with minimal possibility of suture/cornea contact. The remainder of the wound is closed in two layers; care is taken not to penetrate the underlying conjunctiva and cause cornea/suture material contact. SURGERY FOR ECTROPION Ectropion is rarely a serious problem for affected patients unless it is severe or accompanied by entropion in the so-called diamond-eye conformation. If correction of ectropion is required, the simplest approach, which suffices in most cases, is a lid shortening technique involving the removal of a wedge of eyelid skin (as described above under eyelid defect repair ). The wedge of skin to be removed can be the part of the eyelid, which is everted (usually the center of the lower lid). Alternatively, a wedge of skin lateral to the everted area of lid can be removed, resulting in a straightening out of the everted lid during closure of the defect. SURGERY FOR ENTROPION IN PATIENTS WITH NORMAL LID LENGTH A Hotz-Celsus procedure (Fig.2) is employed to correct entropion in patients with normal eyelid length (Fig. 3a). To determine how much tissue is to be removed and where the widest part of the wound is to be placed, it is of utmost importance that the patient is carefully assessed prior to surgery and without the use of sedatives. The affected lid should be manually everted to gain an idea how much excessive skin is present. In addition, the eyelid skin in contact with the cornea and tear film may be depigmented which also can be a helpful guide-mark for the extent of skin excision required (Fig 3b). It may be helpful to draw a diagram prior to surgery, as the eyelid position may dramatically change once anesthesia is induced. The skin incision is outlined with a scalpel blade, starting approximately 2-3 mm away from the eyelid margin (Fig. 3c). This distance allows optimal eversion of the lid whilst secure suture placement is still possible. Scarring is minimized as the incision is made in the non-hairy skin. The outlined skin is excised using Steven s tenotomy scissors to an adequate depth (including part of the orbicularis oculi muscle, which is often difficult to distinguish from the palpebral connective tissue) but care is taken not to perforate the palpebral conjunctiva (Fig. 3d). Wound closure is carried out with evenly placed sutures, starting in the middle of the incision. Subsequent sutures are placed to split the remaining wound in equal parts, ensuring even spacing of the sutures (Fig. 3f). Knots are tightened firmly and rotated away from the eyelid.
Fig. 2 Schematic drawing of a Hotz-Celsus procedure Fig. 3a Fig. 3b
Fig. 3c Fig. 3d Fig. 3e Fig. 3f Fig. 3g Fig. 3h Fig. 3 a -h: Hotz-Celsus procedure 3 a: pre-operative entropion 3 b: eyelid in correct position - note macerated and depigmented eyelid skin due to contact with tears 3 c: delineated skin incision - note distance of proximal incision to eyelid margin (approx 2-3 mm) 3 d: wound following removal of skin and subcuticular tissue (incl orbicularis oculi muscle fibres) 3 e: closure of wound with 6/0 vicryl on a P-needle 3 f: injection of subconjunctival local anaesthetic (different patient) 3 g: immediate post-operative appearance - note degree of ectropion and chemosis associated with local anaesthetic injection (different patient) 3 h: appearance of patient 10 days post-operatively Immediately upon closure of the eyelid wounds, local anesthetic can be applied into the surgical site with a 26-gauge needle (Fig. 3f). The author routinely uses ropivicaine 0.5%, which will provide analgesia of 4-6 hours duration. In most patients, 0.5-1ml is infiltrated into the connective lid tissue but care must be taken not to exceed the toxic dose based on the patient s weight. There is usually some conjunctival swelling present after the injection of local anaesthetic, which will result in the appearance of a mild ectropion - which is acceptable at this point and will resolve over the next 24 hours. The patient is fitted with an Elizabethan collar to prevent self-trauma until
healing of the eyelid wounds has occurred (approximately 10 days). Post-operatively, the following medication is prescribed: Application of broad spectrum antibiotic ointment tid to the affected eyelid/s A 10-day course of systemic NSAID s Depending on the general condition of the patient s skin, a 7-10 day course of appropriate systemic antibiotics REFERENCES Gelatt KN, Gelatt JP Veterinary Ophthalmic Surgery (2011) Nasisse MP Surgical Management of Ocular Disease; In The Veterinary Clinics of North America (Small Animal Practice) 1997, 27 (%) Stades FC, Gelatt KN Diseases and Surgery of the Canine Eyelid. In Veterinary Ophthalmology, Editor Gelatt, KN, 4 th Edition, Vol II, Ch 11, p563-617