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of several procedures and referral to a board-certified ophthalmologist may be warranted. Careful consultation with the owner is also essential as many do not wish to permanently alter the “diamond eye” appearance. The purpose of this lecture (and the next) will be to aid the small animal practitioner in proper surgical preparation, ensure the correct diagnosis of various eyelid abnormalities, choose the most appropriate surgical repair, and provide the practitioner with some guidelines concerning referral.
General Therapeutic Considerations for Adnexal Surgery
Most corrective eyelid surgeries require general anesthesia. A thorough physical examination with appropriate pre-operative bloodwork is indicated especially in middle-aged to older dogs. When corrective eyelid surgery is planned to remove an eyelid mass, more complete pre-surgical work-up is often indicated (for example, FNA or small incisional biopsy if a malignancy
is suspected to plan for adequate surgical margins, thoracic radiographs to look for evidence of lung metastasis, lymph node aspirates). The majority of canine eyelid masses are benign (e.g. sebaceous adenomas, papillomas, histiocytomas), however feline eyelid masses are not as common in practice and are more likely to
be malignant (e.g. squamous cell carcinoma, basal cell carcinoma). In this author’s opinion, any eyelid mass removed from a dog or a cat should be submitted for histopathologic evaluation. Malignant eyelid tumors may require additional surgery or ancillary treatment. Proper head position is important to successful surgical outcome and may be facilitated with sandbags or surgical vacuum packs. Careful surgical planning to avoid over-correction is essential. For example, entropion or eyelid agenesis may be complicated by distichiasis, trichiasis, and/or corneal ulceration, further exacerbating the primary eyelid abnormality. Post-operative use of an E-collar is usually necessary to prevent patient rubbing and premature wound dehiscence. If the patient is evaluated a few days or weeks before surgery is planned, this author finds it helpful to teach owners how to train dogs to wear an E-collar prior to surgery, making the post-operative period less stressful for both owner and pet.
The eyelids are highly vascular. With proper pre-operative planning, surgical technique, and post-operative care, most corrective eyelid procedures carry a favorable prognostic outcome. Care must be taken to avoid over-correction of an eyelid abnormality. Meticulous anatomic repair of wounds at the eyelid margin is critical to the preservation of corneal clarity. These details will
be discussed in the second half of this two-part lecture series.
Patient preparation
This will be discussed in more detail during lecture.
In general, this author prefers minimal clipping when possible and a dilute betadine solution (1:20 to 1:50)
to prepare the globe, conjunctiva, and surrounding periocular area for ophthalmic surgery. Briefly: 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® may 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 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 dilution is prepared as follows:
• 1/50 dilution is used for cornea and conjunctiva
o 10 ml stock Povidone-iodine 10% into 490 ml saline 0.9%
• 1/10 dilution is used for the periorbital skin
o 0 ml stock Povidone-iodine 10% in 450 ml saline 0.9%
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 of the 1/10 Povidone-iodine solution; 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
An Urban Experience
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